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Wyszukujesz frazę "component analysis" wg kryterium: Temat


Tytuł:
Yield component analysis with SYCA and TDP in fodder pea.
Autorzy:
Gołaszewski, Janusz
Idźkowska, Maria
Milewska, Jadwiga
Koczowska, Irena
Powiązania:
https://bibliotekanauki.pl/articles/2198817.pdf
Data publikacji:
2001-12-20
Wydawca:
Instytut Hodowli i Aklimatyzacji Roślin
Tematy:
yield component analysis
sequential yield component analysis
SYCA
two-dimensional partitioning
TDP
fodder pea
Opis:
The paper presents some theoretical assumptions of the SYCA (Sequential Yield Component Analysis) and the application of SYCA followed by TDP (Two-dimensional Partitioning) to analysis of the data from a plant breeding experiment with fodder pea. Partially balanced incomplete block design with 25 morphologically different breeding forms in 4 replications was applied. In both methods of data analysis plant height was the first trait in a sequence of independent traits, followed by different traits depending on the method.The results of the analyses proved that in a morphologically highly differentiated population of fodder pea the contribution of plant height to the yield variability is reduced, with plant height to the first pod being one of the traits that have a significant effect on yield. According to the SYCA method, when the pea forms were divided into groups of plants similar in height, the effect of plant height as the first yield component was high and significant. Generally, the higher were the plants in the groups, the smaller was the share of the trait in the yield, although still relatively high and significant. For the purpose of yield component analysis in pea it is recommendable to divide the breeding material to groups of plants of a similar height.As for the other yield components, the highest contribution into the final yield was attributed to the number of nodes with pods by plant height and seed weight by number of seeds calculated according to the SYCA and the number of nodes with pods calculated according to the TDP method, respectively.The authors, who have used the two yield component analyses for several years, have gained enough experience to claim that the two methods can become effective statistical tools for the elaboration of yield components. Moreover, they can be useful not only in plant breeding studies but also in many other types of agricultural experimentation.
Źródło:
Plant Breeding and Seed Science; 2001, 45, 2; 77-85
1429-3862
2083-599X
Pojawia się w:
Plant Breeding and Seed Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Principal Component Analysis and Cluster Analysis In Multivariate Assessment of Water Quality
Autorzy:
Jankowska, J.
Radzka, E.
Rymuza, K.
Powiązania:
https://bibliotekanauki.pl/articles/124319.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
principal component analysis
water quality
cluster analysis
Opis:
This paper deals with the use of multivariate methods in drinking water analysis. During a five-year project, from 2008 to 2012, selected chemical parameters in 11 water supply networks of the Siedlce County were studied. Throughout that period drinking water was of satisfactory quality, with only iron and manganese ions exceeding the limits (21 times and 12 times, respectively). In accordance with the results of cluster analysis, all water networks were put into three groups of different water quality. A high concentration of chlorides, sulphates, and manganese and a low concentration of copper and sodium was found in the water of Group 1 supply networks. The water in Group 2 had a high concentration of copper and sodium, and a low concentration of iron and sulphates. The water from Group 3 had a low concentration of chlorides and manganese, but a high concentration of fluorides. Using principal component analysis and cluster analysis, multivariate correlation between the studied parameters was determined, helping to put water supply networks into groups according to similar water quality.
Źródło:
Journal of Ecological Engineering; 2017, 18, 2; 92-96
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Principal Component Analysis in the Study of Structure of the Best Polish Decathlon Competitors from the Period between 1985–2015
Autorzy:
Dziadek, Bartosz
Iskra, Janusz
Przednowek, Krzysztof
Powiązania:
https://bibliotekanauki.pl/articles/1030587.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Szczeciński. Wydawnictwo Naukowe Uniwersytetu Szczecińskiego
Tematy:
decathlon
principal component analysis
sport career
Opis:
The modern decathlon is a sport consisting of ten different events held over two days, played by men. Depending on the complexity of combined events, variety of events (runs, throws, jumps), the multi-stage, time-consuming and difficult training process the sport is considered as one of the most difficult. The analysis of careers of the best decathlon participants and applying advanced data-mining methods can help define the patterns occurring between each decathlon event and the final result. The research material encompasses career data of the 25 top competitors from Poland in years 1985–2015. Principal component analysis (PCA) was used in the research in order to designate new uncorrelated variables (components), representing input data across a new plane. Data analysis involved appointment of correlations between the events, determining the number of main components taken into account in further studies, analysis of the weight of each variable in formation of main components as well as visualisation and interpretation of results in the new plane described by the determined main components. Through the implementation of PCA method in the process of analysis it was possible to designate over 69% of compound data volatility with the use of the first three components. The first component, comprised of seven variables, displays the largest share in the total variability. The study of the relationship between variables in the new plane displayed strong correlations between sprint events (100 m, 110 m hurdles) and long jump and pole vault. No correlations between the 1500 m run and other events were found.
Źródło:
Central European Journal of Sport Sciences and Medicine; 2018, 23, 3; 77-87
2300-9705
2353-2807
Pojawia się w:
Central European Journal of Sport Sciences and Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
PCA based modification of SIFT-like methods for object class recognition
Autorzy:
Owczarek, A.
Powiązania:
https://bibliotekanauki.pl/articles/115449.pdf
Data publikacji:
2011
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
object recognition
principle component analysis
SIFT
Opis:
This paper discusses a novel PCA based modification of standard SIFT and PCA-SIFT algorithms for the purpose of object class recognition. New descriptors intended to be simultaneously distinctive enough to describe the difference between features belonging to separate categories and general enough to capture the variations among features from the same class are proposed. The experimental results, gained for a test database, showing the reliability of introduced approach are presented.
Źródło:
Challenges of Modern Technology; 2011, 2, 1; 23-26
2082-2863
2353-4419
Pojawia się w:
Challenges of Modern Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wykorzystanie metody PCA i ICA do analizy sygnału EEG w kontekście usuwania zakłóceń
Use of PCA and ICA methods for analysis of EGG signal in context of removal of artefacts
Autorzy:
Paszkiel, S.
Powiązania:
https://bibliotekanauki.pl/articles/154789.pdf
Data publikacji:
2013
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
analiza artefaktów
analiza składowych głównych
analiza składowych niezależnych
EEG
analysis of artefacts
principal component analysis
independent component analysis
Opis:
W artykule przedstawiono metodę PCA (ang. Principal Component Analysis) oraz ICA (ang. Independent Component Analysis), jako narzędzia pomocne w procesie eliminacji artefaktów z sygnału elektroencefalograficznego. Proces rejestracji sygnału elektroencefalograficznego można zobrazować, jako BSS (ang. Blind Signals Separation). Dzięki temu możliwe jest dokonywanie estymacji nieznanych sygnałów źródłowych oraz ekstrakcji niepożądanych sygnałów zakłócających, w zakresie ich późniejszej eliminacji. W tym celu konieczne jest doskonalenie metod weryfikacji i eliminacji artefaktów z sygnału EEG. W artykule opisano możliwość zastosowania powyższych metod w zakresie sygnału EEG oraz zrealizowane zostało porównanie skuteczności ich działania.
: In the paper there are presented the Principal Component Analysis (PCA) and the Independent Component Analysis (ICA) as useful tools for elimination of artefacts in an electroencephalographic signal. The process of registration of the electroencephalographic signal can be described as BSS - Blind Signals Separation. It is possible to estimate unknown source signals and to extract intrusive disturbing signals in terms of their subsequent elimination. It is necessary to improve the methods of verification and elimination of artefacts from an EEG signal. The Brain Computer Interface (BCI) technology is presented briefly in the first part of the paper. EEG signal characteristics and its acqui-sition with the non-invasive method are described in the second part. Next, there is discussed the possibility of using the PCA and ICA methods in terms of analysis of an EEG signal. Comparison of the effectiveness of these methods is presented as well. A general profile of the EEG signal processing is shown in Fig. 1. An example of use of the infomax algorithm for a real EEG signal is depicted in Fig. 2. Fig. 3 shows an exemplary Event-Related Potential (ERP) of the EEG signal.
Źródło:
Pomiary Automatyka Kontrola; 2013, R. 59, nr 3, 3; 204-207
0032-4140
Pojawia się w:
Pomiary Automatyka Kontrola
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The use of some morphological traits for the assessment of genetic diversity in spinach (Spinacia oleracea L.) landraces
Autorzy:
Ebadi-Segheloo, Asghar
Asadi-Gharneh, Hossein ali
Mohebodini, Mehdi
Janmohammadi, Mohsen
Nouraein, Mojtaba
Sabaghnia, Naser
Powiązania:
https://bibliotekanauki.pl/articles/2199739.pdf
Data publikacji:
2014-06-19
Wydawca:
Instytut Hodowli i Aklimatyzacji Roślin
Tematy:
breeding
cluster analysis
diversity
landraces
principal component analysis
Opis:
Investigation of native accessions of spinach (Spinacia oleracea L.) would be aid in the development of new genetically improved varieties, so in this research 121 spinach landraces, collected from the various spinach growing areas of Iran, were evaluated to determine their diversity using several agro-morphological traits. High coefficients of variation (CV) were recorded in fresh yield, leaf area and dry yield. Using principal component (PC) analysis, the first three PCs with eigenvalues more than 0.9 contributed 80.56% of the variability among accessions. The first PC was related to leaf yield performance (fresh and dry yields, leaf numbers at flowering and lateral branches) while the PC2 was related to leaf characteristic (leaf width, petiole length, petiole diameter and leaf area). The third PC was related to seed characteristic (seed yield and 1000-seed weight) and was named as seed property component. The 121 spinach landraces were grouped into six clusters using cluster analysis. Each cluster had some specific characteristics of its own and the clusters I and II were clearly separated from clusters III and V and also from clusters IV and VI. The studied accessions are an important resource for the generation of a core collection of spinach in the world. The results of present research will support tasks of conservation and utilization of landraces in spinach breeding programs.
Źródło:
Plant Breeding and Seed Science; 2014, 69; 69-80
1429-3862
2083-599X
Pojawia się w:
Plant Breeding and Seed Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A COMPARATIVE STUDY OF FastICA AND GRADIENT ALGORITHMS FOR STOCK MARKET ANALYSIS
Autorzy:
Nermend, Kesra
Rajihy, Yasen
Powiązania:
https://bibliotekanauki.pl/articles/452923.pdf
Data publikacji:
2014
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Katedra Ekonometrii i Statystyki
Tematy:
independent component analysis
nangaussianity
negentropy
stock market analysis
Opis:
In this paper we proved that a fast fixed point algorithm known as FastICA algorithm depending on maximization the nongaussianity by using the ne-gentropy approach is one of the best algorithm for solving ICA model. We compare this algorithm with Gradient algorithm. The Abu Dhabi Islamic Bank (ADIB) used as illustrative example to evaluate the performance of these two algorithms. Experimental results show that the FastICA algorithm is more robust and faster than Gradient algorithm in stock market analysis.
Źródło:
Metody Ilościowe w Badaniach Ekonomicznych; 2014, 15, 1; 142-152
2082-792X
Pojawia się w:
Metody Ilościowe w Badaniach Ekonomicznych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Taxonomic position of Pinus ceciliae (Pinaceae) endemic for Balearic Islands as revealed on needle characteristics
Autorzy:
Boratynska, K.
Tomaszewski, D.
Montserrat, J.M.
Marek, S.
Boratynski, A.
Powiązania:
https://bibliotekanauki.pl/articles/2077667.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
biometry
discrimination analysis
Pinus halepensis
Principal Component Analysis
Opis:
The Cecilian pine (Pinus ceciliae) is endemic to Balearic islands (Spain). It is a small taxon, some- times treated as synonym of Aleppo pine (P. halepensis), to which is closely related, differing mainly with dense crown shape and upright branches. The other characteristics, which differ between P. ceciliae and P. halepensis concern the cone scale and needle length only. We examined biometrically needles of Cecilian pine from Mallorca (5 tress) and Menorca (9 trees) islands, and compared them to Aleppo pine populations rep- resented by 30 trees from each island. Each tree was represented by 5 needles, and they were studied with respect to 17 morphological and anatomical characteristics. We detected that needles of the Cecilian pine were smaller, but only when compared to the Aleppo pine from the same island. In general, this difference was also observed in the number of resin canals, number of stomata and stomatal rows. Interestingly, the proportions of the needle dimensions pattern were similar in both taxa. In conclusion we stated the results support the taxonomic rank of Cecilian pine as a variety, Pinus halepensis var. ceciliae (Llorens & L.Llorens) L.Llorens, Fl. Països Catalans, 1: 197 (1984)
Źródło:
Dendrobiology; 2019, 82; 8-16
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The quality of public finance in the light of fiscal governance concept: implications for the European Union countries
Autorzy:
Kargol-Wasiluk, Aneta
Wildowicz-Giegiel, Anna
Powiązania:
https://bibliotekanauki.pl/articles/22446543.pdf
Data publikacji:
2018
Wydawca:
Instytut Badań Gospodarczych
Tematy:
public finance
quality
fiscal governance
principal component analysis
Opis:
Research background: The research area on the quality of public finance (QPF) appears to be intellectually attractive. In the light of the challenges of the 21st century, public finance should be characterized by adequate quality, ensuring effective implementation of the economic functions of government. The problem of QPF is increasingly more frequent in the face of a deteriorating fiscal situation of most countries in Europe and around the world. Hence, it is worth considering which factors determine the quality of public finance. Purpose of the article: This article aims to show the possibility of assessing the quality of public finance in the light of fiscal governance concept.  The identification of the key components of QPF seems to be useful from the point of view of empirical research, and can be implemented to assess the quality of public finance in the EU?28. Methods: Descriptive analysis along with principal component analysis (PCA) was implemented to indicate dimensions of QPF. Findings & Value added: The quality of public finance consists of a well-designed fiscal rules (numerical and non-numerical) and institutions, as well as structural reforms. The obtained results allow to characterize the quality of public finance through the prism of six identified principal components. They have a mixed character, two of them are partly or totally related to the institutional aspects of public finance, which proves their importance in the process of improving the quality of public finance. Improving the quality of public finance remains a key challenge for policy makers in the EU. The growing impact of globalization and the aging population also cause the need to improve the qualitative aspects of fiscal policy. The study contributes to the literature on public finance, particularly in the empirical dimension through broadening the knowledge on institutional factors which can be used to measure QPF index. The results of research have certainly enriched the existing knowledge on the phenomenon of QPF and the ways of its measurement.
Źródło:
Equilibrium. Quarterly Journal of Economics and Economic Policy; 2018, 13, 3; 411-426
1689-765X
2353-3293
Pojawia się w:
Equilibrium. Quarterly Journal of Economics and Economic Policy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multi-trait evaluation of value for cultivation and use of early maturing edible potato cultivars registered in Poland
Autorzy:
Rymuza, K.
Powiązania:
https://bibliotekanauki.pl/articles/123780.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
edible potato
potato cultivar
principal component analysis
cluster analysis
Opis:
The work presents an analysis of diversity and comparison of value for cultivation and use of early maturing potato cultivars registered with the Polish National Register of Cultivars. The comparison was based on 17 yield and appearance traits and quality attributes of tubers as well as their resistance to diseases. The analysis employed the following multi-dimensional statistical methods: principal component analysis and cluster analysis. The principal component analysis revealed that over 70% of the total variation was associated with the first 6 principal components. Cluster analysis yielded 4 groups of genotypes. The first group consisted of the cultivars which produced tubers with the most shallow eyes, the best flavour and the least severe darkening of raw flesh. The cultivars in the second group produced high yields and were low in starch, dry matter and glycoalkaloids. The tubers of cultivars which were classified into the third group had the highest starch, dry matter and vitamin C contents. However, they produced the lowest yields and were quite susceptible to most diseases. The fourth group was made up of high-yielding cultivars which tended to accumulate glycoalkaloids but were most resistant to hollow heart in tubers.
Źródło:
Journal of Ecological Engineering; 2015, 16, 1; 50-56
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Comprehensive Overview of the Impacting Factors on a Lithium-Ion-Battery’s Overall Efficiency
Autorzy:
Kremzow-Tennie, Simeon
Scholz, Tobias
Pautzke, Friedbert
Popp, Alexander
Fechtner, Heiko
Schmuelling, Benedikt
Powiązania:
https://bibliotekanauki.pl/articles/2175925.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
battery simulation
battery efficiency
component analysis
simulation technology
battery analysis
Opis:
This comprehensive overview of the impacting factors on lithium-ion-battery’s (LIB) overall efficiency presents the most relevant influencing factors on a battery’s performance. Dissected into their respective short-term and long-term influences, the working principles behind the efficiency influencing factors are presented. With a strong focus on battery characterisation, charge-profiles and battery management systems (BMSs), the authors present results of their own practical research with a detailed literary analysis, allowing a broad coverage of the complex topic. Finally, the authors present a principle model that indicates the interactions be-tween the different involved components of the battery.
Źródło:
Power Electronics and Drives; 2022, 7, 42; 9--28
2451-0262
2543-4292
Pojawia się w:
Power Electronics and Drives
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Geomorphic Control on Soil Erosion – a Case Study in the Subarnarekha Basin, India
Autorzy:
Kathwas, Amar Kumar
Patel, Nilanchal
Powiązania:
https://bibliotekanauki.pl/articles/2088182.pdf
Data publikacji:
2021
Wydawca:
Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Tematy:
geomorphological feature
soil erosion
USLE
principal component analysis
Opis:
Geomorphology depicts the qualitative and quantitative characteristics of both terrain and landscape features combined with the processes responsible for its evolution. Soil erosion by water involves processes, which removes soil particles and organic matter from the upper sheet of the soil surface, and then transports the eroded material to distant location under the action of water. Very few studies have been conducted on the nature and dynamics of soil erosion in the different geomorphologic features. In the present investigation, an attempt has been made to assess the control of geomorphologic features on the soil loss. Universal Soil Loss Equation (USLE) was used to determine soil loss from the various geomorphological landforms. Principal component analysis (PCA) was implemented on the USLE parameters to determine the degree of association between the individual principal components and the USLE-derived soil loss. Results obtained from the investigation signify the influence of the various landforms on soil erosion. PC5 is found to be significantly correlated with the USLE-derived soil loss. The results ascertained significant association between the soil loss and geomorphological landforms, and therefore, suitable strategies can be implemented to alleviate soil loss in the individual landforms.
Źródło:
Polish Journal of Soil Science; 2021, 54, 1; 1-24
0079-2985
Pojawia się w:
Polish Journal of Soil Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The application of principal component analysis (pca) for the study of the spanish tourist demand
Autorzy:
González, María Jesús González
Pascual, María-Eva Vallejo
Powiązania:
https://bibliotekanauki.pl/articles/1051397.pdf
Data publikacji:
2018-12-30
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Tematy:
Spain
autonomous communities
tourist demand
principal component analysis
Opis:
The objective of this study is the characterisation of the Spanish autonomous communities as tourist destinations for Spanish trips, based on the activities carried out, using the principal component method. The Spanish tourist is not only motivated by the sun and beach. This paper aims to clarify how Spanish people consider other tourist destinations. We contrast how frequently other types of tourism are valued when choosing their destination within the Spanish geography. Inland tourism, sports tourism, entertainment as well as gastronomy are becoming increasingly important.
Źródło:
Quaestiones Geographicae; 2018, 37, 4; 43-52
0137-477X
2081-6383
Pojawia się w:
Quaestiones Geographicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quantum image classification using principal component analysis
Autorzy:
Ostaszewski, M.
Sadowski, P.
Gawron, P.
Powiązania:
https://bibliotekanauki.pl/articles/375706.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
some quantum algorithms
quantum image processing
principal component analysis
Opis:
We present a novel quantum algorithm for the classification of images. The algorithm is constructed using principal component analysis and von Neuman quantum measurements. In order to apply the algorithm we present a new quantum representation of grayscale images.
Źródło:
Theoretical and Applied Informatics; 2015, 27, 1; 1-12
1896-5334
Pojawia się w:
Theoretical and Applied Informatics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quality enhancement of eddy-current-based non-destructive evaluation data through independent component analysis
Autorzy:
Frulloni, E.
Fiori, S.
Powiązania:
https://bibliotekanauki.pl/articles/1954088.pdf
Data publikacji:
2004
Wydawca:
Politechnika Gdańska
Tematy:
neural network applications
eddy current testing
independent component analysis
Opis:
The aim of this paper is to examine the performance of an independent component analysis algorithm based on neural networks applied to the solution of an electrical engineering problem related to non-destructive evaluation of conductive objects. The proposed application is assessed through computer experiments carried out on real-world data, which prove the usefulness of this non-destructive evaluation technique.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2004, 8, 3; 359-375
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An identification source of variation on the water quality pattern in the Malacca River basin using chemometric approach
Autorzy:
Hua, A. K.
Powiązania:
https://bibliotekanauki.pl/articles/204612.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
hierarchical cluster analysis
discriminant analysis
principal component analysis
multiple linear
regression analysis
Opis:
The Malacca River basin experienced river water pollution which caused a major deterioration to the ecosystems and environmental health. This study is carried out to assess the water quality data and identify the pattern of water pollution sources in the study area, and also to develop a predictive performance of water quality in the Malacca River basin. A chemometric approach using a combination of HCA, DA, PCA, and MLR, was applied into twenty water quality variables from nine sampling stations that were collected from January until December of 2015 in the river basin. HCA pointed out three clusters, namely Cluster 1 (C1) with low pollution source, Cluster 2 (C2) with moderate pollution source, and Cluster 3 (C3) with high pollution source. In the DA analysis, the results showed 21 variables, 12 variables, and 9 variables for standard mode, forward stepwise mode, and backward stepwise mode, respectively. Meanwhile, the PCA indicated that the main source of pollutants is detected from residential, industrial, commercial, agricultural, animal livestock, as well as forest land. Among the three models developed from MLR analysis, C3 with a high pollution source is detected to be the most suitable model to be used for the prediction of Water Quality Index in the Malacca River basin. This study proposed for an effective river water quality management by having new water quality monitoring network to be designed for more practical use in order to reduce time and effort, as well as cost saving purposes.
Źródło:
Archives of Environmental Protection; 2018, 44, 4; 111-122
2083-4772
2083-4810
Pojawia się w:
Archives of Environmental Protection
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new method for detecting cross-inhibition effects in the environmental biocatalytic processes
Autorzy:
Herke, Z.
Maskow, T.
Nemeth, Z.I.
Powiązania:
https://bibliotekanauki.pl/articles/80851.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
biocatalysis
microorganism
enzyme
bioremediation
inhibition
modelling
regression analysis
principal component analysis
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2015, 96, 4
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wavelets and principal component analysis method for vibration monitoring of rotating machinery
Autorzy:
Bendjama, H.
Boucherit, M. S.
Powiązania:
https://bibliotekanauki.pl/articles/949212.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
vibration
fault diagnosis
wavelet analysis
principal component analysis, squared
prediction error
Opis:
Fault diagnosis is playing today a crucial role in industrial systems. To improve reliability, safety and efficiency advanced monitoring methods have become increasingly important for many systems. The vibration analysis method is essential in improving condition monitoring and fault diagnosis of rotating machinery. Effective utilization of vibration signals depends upon effectiveness of applied signal processing techniques. In this paper, fault diagnosis is performed using a combination between Wavelet Transform (WT) and Principal Component Analysis (PCA). The WT is employed to decompose the vibration signal of measurements data in different frequency bands. The obtained decomposition levels are used as the input to the PCA method for fault identification using, respectively, the Q-statistic, also called Squared Prediction Error (SPE) and the Q-contribution. Clearly, useful information about the fault can be contained in some levels of wavelet decomposition. For this purpose, the Q-contribution is used as an evaluation criterion to select the optimal level, which contains the maximum information.Associated to spectral analysis and envelope analysis, it allows clear visualization of fault frequencies. The objective of this method is to obtain the information contained in the measured data. The monitoring results using real sensor measurements from a pilot scale are presented and discussed.
Źródło:
Journal of Theoretical and Applied Mechanics; 2016, 54, 2; 659-670
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Association between dietary patterns and cardiovascular risk factors in a selected population of Lower Silesia (PURE Study Poland)
Autorzy:
Czekajlo, A.
Różańska, D.
Zatońska, K.
Szuba, A.
Regulska-Ilow, B.
Powiązania:
https://bibliotekanauki.pl/articles/2081935.pdf
Data publikacji:
2018
Wydawca:
Instytut Medycyny Wsi
Tematy:
risk factors
cardiovascular diseases
principal component analysis
dietary patterns
Opis:
Introduction. Dietary pattern analysis is used to describe the dietary habits of a selected population. In many studies, dietary patterns (DPs) have been associated with risk factors for cardiovascular disease (CVD). The aim of the study was to assess the association between dietary patterns identified in the population of Lower Silesia, Poland, with anthropometric and biochemical risk factors for CVD. Materials and method. The study group included 2,025 participants of the Prospective Urban Rural Epidemiological (PURE) Study. Dietary intake was evaluated based on data from the Food Frequency Questionnaire (FFQ). Dietary patterns were derived using principal component analysis (PCA). The relationship between DPs and body mass index (BMI), waist circumference, waist-hip ratio, blood pressure, total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides and fasting glucose level, was assessed. Results. Three dietary patterns identified in the study explained 35.6% of total variance. The ‘fruit, vegetables & dairy’ DP, characterized by a high intake of vegetables, fruits, nuts, seeds, raisins, milk and low-fat dairy, was associated with improved lipid profile and anthropometric measures, lower diastolic blood pressure and lower fasting glucose concentration. ‘Traditional’ and ‘fat & sugar’ DPs were unfavourably associated with most of the risk factors for CVD presented in this study. Conclusions. Dietary patterns identified in this study were differently related to selected anthropometric and biochemical risk factors for CVD. ‘Fruit, vegetables & dairy’ DP was favourably associated with the biochemical and anthropometric CVD risk factors, and was characterized by higher nutritional value in comparison with ‘traditional’ and ‘fat & sugar’ DPs.
Źródło:
Annals of Agricultural and Environmental Medicine; 2018, 25, 4; 635-641
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wavelength-sensitive-function-based spectral reconstruction using segmented principal component analysis
Autorzy:
Wu, G.
Shen, X.
Liu, Z.
Zhang, J.
Powiązania:
https://bibliotekanauki.pl/articles/174199.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
spectral reconstruction
wavelength-sensitive function
segmented principal component analysis
Opis:
Spectral images provide richer information than colorimetric images. A high-dimensional spectral data presents a challenge for efficient spectral reconstruction. In conventional reconstruction methods it is very difficult to obtain good spectral and colorimetric accuracy simultaneously. In this paper, a segmented principal component analysis (SPCA) method and a weighted segmented principal component analysis (wSPCA) method are proposed for efficient reconstruction of spectral color information. The methods require, firstly, partitioning the complete spectrum of wavelengths into two subgroups, considering the sensitivity of human visual system. Then the classical principal component analysis (PCA) carried out each subgroup of data separately. The results indicated that the spectral and colorimetric accuracy of the SPCA and wSPCA outperformed the PCA and weighted PCA, and wSPCA clearly retained more color visual information.
Źródło:
Optica Applicata; 2016, 46, 3; 365-374
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of complex-valued functional magnetic resonance imaging data: are we just going through a "phase"?
Autorzy:
Calhoun, V.
Adali, T.
Powiązania:
https://bibliotekanauki.pl/articles/201555.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
fMRI
independent component analysis
ICA
phase
complex-valued
brain
Opis:
Functional magnetic resonance imaging (fMRI) data are acquired as a natively complex data set, however for various reasons the phase data is typically discarded. Over the past few years, interest in incorporating the phase information into the analyses has been growing and new methods for modeling and processing the data have been developed. In this paper, we provide an overview of approaches to understand the complex nature of fMRI data and to work with the utilizing the full information, both the magnitude and the phase. We discuss the challenges inherent in trying to utilize the phase data, and provide a selective review with emphasis on work in our group for developing biophysical models, preprocessing methods, and statistical analysis of the fully-complex data. Of special emphasis are the use of data-driven approaches, which are particularly useful as they enable us to identify interesting patterns in the complex-valued data without making strong assumptions about how these changes evolve over time, something which is challenging for magnitude data and even more so for the complex data. Finally, we provide our view of the current state of the art in this area and make suggestions for what is needed to make efficient use of the fully-complex fMRI data.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2012, 60, 3; 371-418
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multivariate and Geostatistical Analyses of Groundwater Quality for Acid Rock Drainage at Waste Rock and Tailings Storage Site
Autorzy:
Adadzi, Patrick
Allwright, Amy
Fourie, Francois
Powiązania:
https://bibliotekanauki.pl/articles/2202307.pdf
Data publikacji:
2022
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
acid rock drainage
groundwater
correlation matrix
principal component analysis
geostatistical analysis
Opis:
A multi-disciplinary approach is indispensable for adequate acid rock drainage (ARD), mineral leaching impact, and groundwater management. Groundwater is a valuable resource, and it is critical to protect as well as mitigate the effects of pollution such as ARD in the mining environment. Mine waste storage facilities (waste rocks and tailings) are potential ARD sources capable of degrading groundwater reserves. This research investigated and reported the application of a case study of multivariate statistical and spatial variability of selected parameters associated with ARD in groundwater around WRD and TSF at mine sites. Water quality analysis data of seventy water samples from 10 boreholes located at the WRD and TSF mine were utilised in this study. The correlation matrix and principal components analysis was applied to the data set to determine the associated variability in groundwater in relation to ARD. Geostatistical analysis was used to produce contour maps to ARD principal components of the study site, using ordinary kriging of the best fit models. The application of multivariate statistical and geospatial analysis in groundwater quality assessment with coupled soil and groundwater modelling of flow and transport at waste rock dump and tailings storage sites provides an essential tool for exploratory data analysis, and spatial extent determination of the relationship between various data sets significant to acid rock drainage.
Źródło:
Journal of Ecological Engineering; 2022, 23, 12; 203--216
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stylistyka ceramiki grupy wschodniej kultury amfor kulistych – ujęcie strukturalne
Pottery style of the eastern group of the Globular Amphora culture – structural analysis
Autorzy:
Sieradzka, Elżbieta
Powiązania:
https://bibliotekanauki.pl/articles/567563.pdf
Data publikacji:
2017
Wydawca:
Uniwersytet Rzeszowski. Instytut Archeologii Uniwersytetu Rzeszowskiego. Muzeum Okręgowe w Rzeszowie
Tematy:
Globular Amphora culture
pottery style
statistical analysis
principal component analysis
network analysis
Opis:
In the classical approach presented by Marzena Szmyt, statistical analysis of the ceramic style of the eastern group of Globular Amphora Culture was based on detailed classification of ornaments and their co-occurrence within grave inventories. This paper introduces an alternative proposition, focusing on structural analysis of decoration of vessels. Additionally, in order to show the distribution of stylistic features among the graves, some elements of the network analysis were implemented.
Źródło:
Materiały i Sprawozdania Rzeszowskiego Ośrodka Archeologicznego; 2017, 38; 13-26
0137-5725
Pojawia się w:
Materiały i Sprawozdania Rzeszowskiego Ośrodka Archeologicznego
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimal Stock Portfolio – Application of Multivariate Statistical Analysis
Optymalny portfel akcji – zastosowanie wielowymiarowej analizy statystycznej
Autorzy:
Konarzewska, Iwona
Powiązania:
https://bibliotekanauki.pl/articles/904809.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
optimal portfolio models
principal component analysis of rates of return
Opis:
Investigating relationship between risk of the Markowitz optimal portfolio and the strength of interdependence for the set of rates of return for portfolio components we state (Konarzewska, 2008, 2012) that the risk measured as variance/standard deviation is slightly sensitive on small disturbance in data set when the series of data are strongly interrelated. What more, portfolio risk rises as the strength of interdependence declines. We have found that if strong linear relationship is present among series, it is important to control the direction between the portfolio weights vector and the eigenvector corresponding to maximal eigenvalue of the correlation/covariance matrix – the ideal situation being orthogonality of the two vectors. These results can be utilized in: the algorithm for pre-selection of investment portfolio components, construction of the optimal investment portfolio models. Both propositions utilize eigenvalue decomposition of the rates of return correlation or covariance matrix. Theoretical results are illustrated by empirical examples for medium-sized firms being components of mWIG40 index on Stock Exchange in Warsaw. We compare optimal portfolios obtained for Markowitz and PCA – aided models.
W artykule przedstawiamy wybrane wyniki teoretyczne na temat konstrukcji optymalnego portfela akcji z wykorzystaniem informacji dostepnej w wyniku przeprowadzenia analizy głównych składowych macierzy kowariancji czy też macierzy korelacji stóp zwrotu z akcji. Wyniki teoretyczne prowadzą do konstrukcji modeli optymalizacyjnych uwzględniajacych redukcję przestrzeni danych do określonej liczby głównych składowych, co udaje się skutecznie przeprowadzić w warunkach silnych związków o charakterze liniowym między szeregami stóp zwrotu z akcji. W pracy prezentujemy wyniki analiz dla modeli Markowitza oraz modeli opartych o analizę głównych składowych na przykładzie sektora średnich spółek na GPW w Warszawie w latach 2009-2011. Badanie empiryczne pokazuje różnice wyników optymalizacji oraz ryzyka portfeli w przypadkach, kiedy korzystamy z macierzy kowariancji albo korelacji.
Źródło:
Acta Universitatis Lodziensis. Folia Oeconomica; 2013, 286
0208-6018
2353-7663
Pojawia się w:
Acta Universitatis Lodziensis. Folia Oeconomica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Inverse method for a one-stage spur gear diagnosis
Autorzy:
Akrout, A.
Tounsi, D.
Taktak, M.
Abbes, M. S.
Haddar, M.
Powiązania:
https://bibliotekanauki.pl/articles/949292.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
Independent Component Analysis (ICA)
source identification
gear mechanism
geometrical defects
Opis:
In this paper, a source separation approach based on the Blind Source Separation (BSS) is presented. In fact, the Independent Component Analysis (ICA), which is the main technique of BSS, consists in extracting different source signals from several observed mixtures. This inverse method is very useful in many fields such as telecommunication, signal processing and biomedicine. It is also very attractive for diagnosis of mechanical systems such as rotating machines. Generally, dynamic responses of a given mechanical system (displacements, accelerations and speeds) measured through sensors are used as inputs for the identification of internal defaults. In this study, the ICA concept is applied to the diagnosis of a one-stage gear mechanism in which two types of defects (the eccentricity error and the localized tooth defect)are introduced. The finite element method allows determination of the signals corresponding to the acceleration in some locations of the system, and those signals may be used also in the ICA algorithm. Hence, the vibratory signatures of each defect can be identified by the ICA concept. Thus, a good agreement is obtained by comparing the expected default signatures to those achieved by the developed inverse method.
Źródło:
Journal of Theoretical and Applied Mechanics; 2015, 53, 3; 617-628
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Physicochemical characterization of synclinal spring water of Taoura, region of Souk Ahras – North East Algeria
Autorzy:
Bouhafs, Fatma
Laraba, Abdelaziz
Powiązania:
https://bibliotekanauki.pl/articles/1841971.pdf
Data publikacji:
2021
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
chemistry
principal component analysis
PCA
pollution
springs
Taoura
water quality
Opis:
The springs of the Taoura region flow from a syncline shaped structure. All resources in the region were mobilized as a result of increased demand. However, the development of anthropic activities and population growth in the area pose risk for groundwater. Analytical results obtained from a series of samplings in November 2017–April 2018, express the quality of water suitable for the irrigation of agricultural land. The highest values are recorded in April 2018 at 20.5 to 21.6°C and pH of 8.0 to 8.2. The study recorded high electrical conductivity from 1390 to 1495 μS∙cm–1 and TDS from 1270 to 1500 mg∙dm–3 in November 2017, which shows important mineralization that characterizes spring water. Physical parameters were measured in situ using a HORIBA multi-parameter probe. Chemical analyses were carried out using NFT 90-005 titration, and nitrogen parameters by DIN 38405-D92 spectrophotometry. Maximum levels of nitrates and phosphates were recorded at 228 and 18.4 mg∙dm–3 respectively. The principal component analysis (PCA) showed a good correlation of the November 2017 period with mineralization parameters. Moreover, there is a strong correlation between the wet period and pollution factors. The two methods of analysis has allowed to distinguish three groups of geochemical water types: a bicarbonate calcium group typical for waters having transited in carbonate horizons. A second chloride calcium group shows basic exchange between water and clay levels, and the third chloride bicarbonate calcium group reveals an enrichment in calcium and chloride, which reflects water circulation with an exchange of the carbonated and evaporitic sedimentary rock matrix.
Źródło:
Journal of Water and Land Development; 2021, 50; 27-37
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Geochemistry of surface sediments from the northwestern Gulf of Mexico : implications for provenance and heavy metal contamination
Autorzy:
Armstrong-Altrin, John S.
Botello, Alfonso V.
Villanueva, Susana F.
Soto, Luis A.
Powiązania:
https://bibliotekanauki.pl/articles/2058576.pdf
Data publikacji:
2019
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Tamaulipas
deep-sea sediments
enrichment factor
contamination
principle component analysis
Opis:
Thirty-five near-surface sediment samples were recovered from the continental shelf and upper slope regions of the north-western (NW) Gulf of Mexico. The geochemical data of the sediments recovered were examined to investigate the weathering intensity, provenance, palaeo-oxygenation condition, and level of heavy metal contamination. The sediments analysed showed a moderate to high intensity of chemical weathering. Major and trace element concentrations indicated a terrigenous origin, closely related to the weathering of rocks rich in aluminosilicates. The results of this study further revealed that major rivers, the Bravo and Soto La Marina, played an important role in delivering sediments to the study area. The concentration of transition trace elements such as Cr, Cu, Ni, and V revealed that the sediments were derived from intermediate rocks such as andesite. The V/Cr, Ni/Co, and Cu/Zn ratios in the sediments were <2, <5, and <1, respectively, suggesting a depositional process occurred under well-oxygenated conditions. Principle Component Analysis (PCA) did not show a significant difference in sediment texture between the continental shelf and slope areas. The enrichment factor (EF) and Geo-accumulation index (lgeo) values were <2 and <1, respectively, suggesting the absence of an anthropogenic input.
Źródło:
Geological Quarterly; 2019, 63, 3; 522--538
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
State-space estimation of soil organic carbon stock
Autorzy:
Timm, L.C.
Ogunwole, J.O.
Obidike-Ugwu, E.O.
Gabriels, D.M.
Powiązania:
https://bibliotekanauki.pl/articles/26250.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
soil
organic carbon
variability
component analysis
organic matter
agricultural management
Opis:
Understanding soil spatial variability and identifying soil parameters most determinant to soil organic carbon stock is pivotal to precision in ecological modelling, prediction, estimation and management of soil within a landscape. This study investigates and describes field soil variability and its structural pattern for agricultural management decisions. The main aim was to relate variation in soil organic carbon stock to soil properties and to estimate soil organic carbon stock from the soil properties. A transect sampling of 100 points at 3 m intervals was carried out. Soils were sampled and analyzed for soil organic carbon and other selected soil properties along with determination of dry aggregate and water-stable aggregate fractions. Principal component analysis, geostatistics, and state-space analysis were conducted on the analyzed soil properties. The first three principal components explained 53.2% of the total variation; Principal Component 1 was dominated by soil exchange complex and dry sieved macroaggregates clusters. Exponential semivariogram model described the structure of soil organic carbon stock with a strong dependence indicating that soil organic carbon values were correlated up to 10.8m.Neighbouring values of soil organic carbon stock, all waterstable aggregate fractions, and dithionite and pyrophosphate iron gave reliable estimate of soil organic carbon stock by state-space.
Źródło:
International Agrophysics; 2014, 28, 2
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electronic noses for monitoring benzene occupational exposure in biological samples of Egyptian workers
Autorzy:
Mohamed, Ehab I.
Khalil, Gihane I.
Abdel-Mageed, Samir M.
Bayoumi, Amani M.
Ramadan, Heba S.
Kotb, Metwally A.
Powiązania:
https://bibliotekanauki.pl/articles/2179801.pdf
Data publikacji:
2013-03-01
Wydawca:
Instytut Medycyny Pracy im. prof. dra Jerzego Nofera w Łodzi
Tematy:
phenol
muconic acid
exhaled air
blood
urine
principal component analysis
Opis:
Objectives: Benzene is commonly emitted in several industries, leading to widespread environmental and occupational exposure hazards. While less toxic solvents have been substituted for benzene, it is still a component of petroleum products and is a trace impurity in industrial products resulting in continued higher occupational exposures in industrial settings in developing countries. Materials and Methods: We investigated the potential use of an electronic nose (e-nose) to monitor the headspace volatiles in biological samples from benzene-exposed Egyptian workers and non-exposed controls. The study population comprised 150 non-smoking male workers exposed to benzene and an equal number of matching non-exposed controls. We determined biomarkers of benzene used to estimate exposure and risk including: benzene in exhaled air and blood; and its urinary metabolites such as phenol and muconic acid using gas chromatography technique and a portable e-nose. Results: The average benzene concentration measured in the ambient air of the workplace of all studied industrial settings in Alexandria, Egypt; was 97.56±88.12 μg/m³ (range: 4.69–260.86 μg/m³). Levels of phenol and muconic acid were signifi cantly (p < 0.001) higher in both blood and urine of benzene-exposed workers as compared to non-exposed controls. Conclusions: The e-nose technology has successfully classifi ed and distinguished benzene-exposed workers from non-exposed controls for all measured samples of blood, urine and the exhaled air with a very high degree of precision. Thus, it will be a very useful tool for the low-cost mass screening and early detection of health hazards associated with the exposure to benzene in the industry.
Źródło:
International Journal of Occupational Medicine and Environmental Health; 2013, 26, 1; 165-172
1232-1087
1896-494X
Pojawia się w:
International Journal of Occupational Medicine and Environmental Health
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A game theoretical study of generalised trust and reciprocation in Poland. [Part] 2, A description of the study group
Autorzy:
Markowska-Przybyła, U.
Ramsey, D. M.
Powiązania:
https://bibliotekanauki.pl/articles/406286.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
Bayesian networks
principal component analysis
social survey
experimental game theory
Opis:
The first article describing this project presented the three games that the participants played: the Ultimatum Game, the Trust Game and the Public Goods Game. This article describes the study group on the basis of a questionnaire regarding where they study and come from, their social contacts, interest in current issues, views on inequality and outlook on life. A description of the migratory decisions of students is given. In particular, two exploratory methods are used to investigate the data’s structure: Bayesian networks and principal component analysis. Bayesian networks are used to illustrate the associations between categorical variables. Principal component analysis is designed to describe latent variables which reflect the associations between numerical variables. We present the results of this analysis and discuss the advantages and disadvantages of these two methods.
Źródło:
Operations Research and Decisions; 2015, 25, 2; 51-73
2081-8858
2391-6060
Pojawia się w:
Operations Research and Decisions
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Unemployment rate for various countries since 2005 to 2012: comparison of its level and pace using functional principal component analysis
Autorzy:
Jaworski, Stanisław
Furmańczyk, Konrad
Powiązania:
https://bibliotekanauki.pl/articles/453714.pdf
Data publikacji:
2012
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Katedra Ekonometrii i Statystyki
Tematy:
B-splines basis system
functional principal component analysis,
unemployment rate
Opis:
We apply the functional principal component analysis to compare the unemployment rate in euro area, Japan and USA since 2005 to 2012. For preprocessing analysis we used B-splines system with roughness penalty for smoothing the data. The analysis enables to reveal the most important type of variation in unemployment rate and its pace's in examined countries.
Źródło:
Metody Ilościowe w Badaniach Ekonomicznych; 2012, 13, 2; 40-47
2082-792X
Pojawia się w:
Metody Ilościowe w Badaniach Ekonomicznych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Using chemometrics to identify water quality in Daya Bay, China
Autorzy:
Wu, M.-L.
Wang, Y.-S.
Sun, C.-C.
Wang, H.
Lou, Z.-P.
Dong, J.-D.
Powiązania:
https://bibliotekanauki.pl/articles/49096.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
robust principal component analysis
water quality
chemometrics
China
cluster analysis
Daya Bay
Opis:
In this paper, chemometric approaches based on cluster analysis, classical and robust principal component analysis were employed to identify water quality in Daya Bay (DYB), China. The results show that these approaches divided water quality in DYB into two groups: stations S3, S8, S10 and S11 belong to cluster A, which lie in Dapeng Cove, Aotou Harbor and the north-eastern part of DYB, where water quality is related mainly to anthropogenic activities. The other stations belong to cluster B, which lie in the southern, central and eastern parts of DYB, where the quality is related mainly to water exchange with the South China Sea. Cluster analysis yields good results as a first exploratory method for evaluating spatial difference, but it fails to demonstrate the relationship between variables and environmental quality on the one hand and the untreated data on the other. However, with the aid of suitable chemometric approaches, the relationship between samples or variables can be investigated. Classical and robust principal component analysis can provide a visual aid for identifying the water environment in DYB, and then extracting specific information about relationships between variables and spatial variation trends in water quality.
Źródło:
Oceanologia; 2009, 51, 2; 217-232
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Use of Multivariate Statistical Analysis of Hydrochemical Data for the Identification of the Geochemical Processes in the Tirana-Fushe Kuqe Alluvial Aquifer, North-Western Albania
Autorzy:
Raço, Endri
Beqiraj, Arjan
Cenameri, Sabina
Jahja, Aurela
Powiązania:
https://bibliotekanauki.pl/articles/2173334.pdf
Data publikacji:
2022
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
Tirana-Fushe Kuqe aquifer
groundwater
multivariate analysis
principal component analysis
hierarchical cluster analysis
Opis:
During the research, 71 groundwater samples were collected over a 300 km2 area of Tirana-Fushe Kuqe alluvial aquifer extension (central-western Albania) and subsequently analyzed for 11 parameters (pH, K+, Na+, Ca2+, Mg2+, HCO3-, Cl-, SO42-, NO3-, TH and TDS). Both geochemical conventional (Piper and Chadha diagrams) methods of groundwater classification and multivariate statistical (principal components analysis – PCA and hierarchical cluster analysis – HCA) methods were applied to the dataset to evidence the geochemical processes controlling groundwater geochemistry evaluation through the aquifer. The conventional geochemical methods revealed four (G1–G4) hydrochemical groups where the dominant group is G2 the samples of which are from unconfined to semiconfined recharge zone and the majority of them have Ca-Mg-HCO3 groundwater. Group G3 includes the samples from the confined coastal aquifer having Na-Cl groundwater. Group G1 includes three groundwater samples of Ca-Mg-SO4 from the central part of the aquifer, while group G4, the samples of which are spatially located between G3 and G2 zones, has Na-HCO3 groundwater. The first four components of the PCA account for 85.35% of the total variance. Component PC1 is characterized by very high positive loadings of TH, Ca2+, and Mg2+, suggesting the importance of dissolution processes in the aquifer recharge zone. Component PC2 is characterized by very high positive loadings in Na+, K+, and Cl-and moderate to high loadings of TDS, revealing the involvement of seawater intrusion and diffusion from clay layers. On the basis of their variable loadings, the first two components are defined as the “hardness” and “salinity”, respectively. The HCA produced four geochemically distinct clusters, C1–C4. The samples of cluster C1 are from the coastal confined aquifer and their groundwater belongs to the Na-Cl type. The samples from cluster C2 are located in the south and east recharge areas and most of them have Ca–Mg–HCO3 groundwater, while the samples from cluster C3, which are located in the northeastern recharge zone, have Mg-Ca–HCO3 groundwater. Finally, cluster C4 includes two groundwater subgroups having Na-Cl-HCO3 and Na-Mg-Cl-HCO3 groundwater in the vicinity of cluster C1 as well as Na-HCO3-Cl and Na-Mg-HCO3-Cl groundwater next to cluster C2 and C3.
Źródło:
Journal of Ecological Engineering; 2022, 23, 8; 327--340
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A comparative analysis of the principal component method and parallel analysis in working with official statistical data
Autorzy:
Holubova, Halyna
Powiązania:
https://bibliotekanauki.pl/articles/10559806.pdf
Data publikacji:
2023-02-24
Wydawca:
Główny Urząd Statystyczny
Tematy:
principal components
principal component analysis
factor analysis
Kaiser criterion
рarallel analysis
simulation
Opis:
The dynamic development of the digitized society generates large-scale information data flows. Therefore, data need to be compressed in a way allowing its content to remain complete and informative. In order for the above to be achieved, it is advisable to use the principal component method whose main task is to reduce the dimension of multidimensional space with a minimal loss of information. The article describes the basic conceptual approaches to the definition of principle components. Moreover, the methodological principles of selecting the main components are presented. Among the many ways to select principle components, the easiest way is selecting the first k-number of components with the largest eigenvalues or to determine the percentage of the total variance explained by each component. Many statistical data packages often use the Kaiser method for this purpose. However, this method fails to take into account the fact that when dealing with random data (noise), it is possible to identify components with eigenvalues greater than one, or in other words, to select redundant components. We conclude that when selecting the main components, the classical mechanisms should be used with caution. The Parallel analysis method uses multiple data simulations to overcome the problem of random errors. This method assumes that the components of real data must have greater eigenvalues than the parallel components derived from simulated data which have the same sample size and design, variance and number of variables. A comparative analysis of the eigenvalues was performed by means of two methods: the Kaiser criterion and the parallel Horn analysis on the example of several data sets. The study shows that the method of parallel analysis produces more valid results with actual data sets. We believe that the main advantage of Parallel analysis is its ability to model the process of selecting the required number of main components by determining the point at which they cannot be distinguished from those generated by simulated noise.
Źródło:
Statistics in Transition new series; 2023, 24, 1; 199-212
1234-7655
Pojawia się w:
Statistics in Transition new series
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Differences between technological and textural parameters of meat from farmed and wildlife red deer (Cervus elaphus) determined by PCA method
Różnice pomiędzy parametrami technologicznymi i teksturalnymi mięsa jeleni (Cervus elaphus) hodowlanych i dziko żyjących określone metodą składowych głównych
Autorzy:
Kral, M.
Snirc, M.
Tremlova, B.
Powiązania:
https://bibliotekanauki.pl/articles/825883.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Technologów Żywności
Tematy:
farmed deer
wildlife animal
red deer
Cervus elaphus
meat
difference
technological parameter
texture parameter
determination
PCA method zob.principal component analysis
principal component analysis
Źródło:
Żywność Nauka Technologia Jakość; 2018, 25, 3
1425-6959
Pojawia się w:
Żywność Nauka Technologia Jakość
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
CDMA wireless system with blind multiuser detector
Autorzy:
Leong, W. Y.
Homer, J.
Powiązania:
https://bibliotekanauki.pl/articles/309140.pdf
Data publikacji:
2006
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
code division multiple access
independent component analysis
blind source separation
Opis:
In this paper we present an approach capable of countering the presence of multiple access interference (MAI) in code division multiple access (CDMA) channels. We develop and implement a blind multiuser detector, based on an independent component analysis (ICA) to mitigate both MAI and noise. This algorithm has been utilized in blind source separation (BSS) of unknown sources from their linear mixtures. It can also be used for estimation of the basis vectors of BSS. The aim is to include an ICA algorithm within a wireless receiver in order to reduce the level of interference in CDMA systems. This blind multiuser detector requires less precise knowledge of the channel than does the conventional single-user receiver. The proposed blind multiuser detector is made robust with respect to imprecise knowledge of the received signature waveforms of the user of interest. Several experiments are performed in order to verify the validity of the proposed learning algorithm.
Źródło:
Journal of Telecommunications and Information Technology; 2006, 1; 69-75
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Alarms management by supervisory control and data acquisition system for wind turbines
Autorzy:
Ramirez, Isaac Segovia
Mohammadi-Ivatloob, Behnam
Márqueza, Fausto Pedro García
Powiązania:
https://bibliotekanauki.pl/articles/1841786.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
alarm management
maintenance management
principal component analysis
SCADA
wind turbines
Opis:
Wind energy is one of the most relevant renewable energy. A proper wind turbine maintenance management is required to ensure continuous operation and optimized maintenance costs. Larger wind turbines are being installed and they require new monitoring systems to ensure optimization, reliability and availability. Advanced analytics are employed to analyze the data and reduce false alarms, avoiding unplanned downtimes and increasing costs. Supervisory control and data acquisition system determines the condition of the wind turbine providing large dataset with different signals and alarms. This paper presents a new approach combining statistical analysis and advanced algorithm for signal processing, fault detection and diagnosis. Principal component analysis and artificial neural networks are employed to evaluate the signals and detect the alarm activation pattern. The dataset has been reduced by 93% and the performance of the neural network is incremented by 1000% in comparison with the performance of original dataset without filtering process.
Źródło:
Eksploatacja i Niezawodność; 2021, 23, 1; 110-116
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the potential for using selected PCA-based methods to analyze the crime rate in Poland
Autorzy:
Misztal, Małgorzata
Powiązania:
https://bibliotekanauki.pl/articles/424843.pdf
Data publikacji:
2019
Wydawca:
Wydawnictwo Uniwersytetu Ekonomicznego we Wrocławiu
Tematy:
crime
criminal offence
multivariate exploratory data analysis
principal component analysis
factorial maps
Opis:
The aim of the paper is to assess the potential for using some selected PCA-based methods to analyze the spatial diversity of crime in Poland during 2000-2017. Classical principal components analysis (PCA) deals with two-way matrices, usually taking into account objects and variables. In the case of data analyzed in the study, apart from two dimensions (objects – voivodships, variables – criminal offences), there is also the dimension of time, so the dataset can be seen as data cube: objects × variables × time. Therefore, this type of data requires the use of methods handling three-way data structures. In the paper the variability of some selected categories of criminal offences in time (2000- -2017) and space (according to voivodships) is analyzed using the between-class and the within-class principal component analysis. The advantage of these methods is, among others, the possibility of the graphical presentation of the results in two-dimensional space with the use of factorial maps.
Źródło:
Econometrics. Ekonometria. Advances in Applied Data Analytics; 2019, 23, 2; 15-32
1507-3866
Pojawia się w:
Econometrics. Ekonometria. Advances in Applied Data Analytics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of Multivariate Statistical Methods to the Hydrochemical Study of Groundwater Quality in the Sahel Watershed, Algeria
Autorzy:
Hakim, Djafer Khodja
Amina, Aichour
Amina, Rezig
Djouhra, Baloul
Ahmed, Ferhati
Powiązania:
https://bibliotekanauki.pl/articles/2173331.pdf
Data publikacji:
2022
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
hydrochemical analysis
water quality
groundwater
principal component analysis
hierarchical cluster analysis
Sahel watershed
Opis:
The quality of groundwater is characterized by several numbers of physical and chemical parameters, which determine the use of water (water supply, irrigation, industry). This search paper is a contribution made to know the hydrochemical characteristics of groundwater in the Sahel sub-catchment which belongs to the large Soummam North basin of Algeria. Different multivariate statistical techniques were used such as principal component analysis (PCA), Hierarchical Cluster Analysis (HCA) and Diagram Analysis. These analyses are exercised to a dataset formed from 37 boreholes with 12 chemical variables over the entire surface of the watershed. The samples were collected in 2016. The 37 boreholes are one of the main water resources that supply the wilaya of Bouira with drinking water and irrigation. The analysis of water quality using different methods (ACP, HCA and Diagram) resulted in two chemical kinds: (Chloride, calcium sulfate and magnesium), and (Bicarbonate calcium and magnesium). The results have shown that 74% of the boreholes were contaminated, the rest of boreholes were characterized by a good quality and they have not suffered any contamination and can be consumed without any risk.
Źródło:
Journal of Ecological Engineering; 2022, 23, 8; 341--349
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multivariate diversity of Polish winter triticale cultivars for spike and other traits.
Autorzy:
Kociuba, Wanda
Mądry, Wiesław
Kramek, Aneta
Ukalski, Krzysztof
Studnicki, Marcin
Powiązania:
https://bibliotekanauki.pl/articles/2199592.pdf
Data publikacji:
2010-12-01
Wydawca:
Instytut Hodowli i Aklimatyzacji Roślin
Tematy:
canonical variate analysis
cluster analysis
cultivars
principal component analysis
spike traits
winter triticale
Opis:
The objective of the present study was to determine the extent and pattern of genotypic diversity for six spike quantitative characters and two other traits in 36 winter triticale cultivars released in Poland, to classify the cultivars into similarity groups (clusters) and to identify those traits, among the studied ones, which mostly discriminated distinguished groups of cultivars. The 36 cultivars, released in the period from 1982 to 1999, were evaluated across three years 2002-2004 at the Experimental Field Station in Czesławice near Nałęczów, Poland. The experiments were carried out on the brown soil with loess subsoil. In each year the one-replicated experimental design was used with 2 m2 plots, rows 20 cm apart, and dense sowing using about 2 cm spacing of seeds. Analyses of variance for each trait data according to the random model (both cultivars and years were assumed to be random factors) were done. To classify and characterize genotypic diversity of the cultivars for the eight traits, the pattern analysis was used. It involved both cluster analysis using Ward’s procedure with a measure of the multivariate similarity among cultivars being Squared Euclidean Distance and canonical variate analysis (CVA) on the basis of cultivar BLUPs for the original traits. Quite different groups of cultivars for the studied traits were found, specially one group was substantially distanced to the others. As it was shown by CVA, spike length and number of spikelets per spike as negatively correlated with number of grains per spikelet in the studied set of the cultivars relatively largest contributed to overall differentiation of the distinguished eight groups and then, these traits best discriminated among the eight cultivar groups in the term of Mahalanobis distance for the considered traits. The 1000 grain weight and grain protein content much less contributed to overall discrimination of the cultivar groups than the previous four traits. The most important agronomic traits characterizing productivity of the spike grain weight and its two components, e.g. number of grains per spikelet and number of grains per spike had least discriminating power for the groups of cultivars. Grain yield per unit area of cereals is a result of spike grain yield and the number of spikes per unit area. In these studies of winter triticale cultivar diversity only grain spike yield and its components were included. Thus, the presented study are a primary evaluating of phenotypic diversity in the cultivars. The further study on the cultivar diversity evaluation for grain yield per unit area and its components is necessary...  
Źródło:
Plant Breeding and Seed Science; 2010, 62; 31-42
1429-3862
2083-599X
Pojawia się w:
Plant Breeding and Seed Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Elucidation of tidal spatial-temporal variation of physico-chemical and nutrient parameters of estuarine water at South Gujarat
Autorzy:
Desai, Nisheeth C.
Kukadiya, Nipul B.
Mehta1, Jignasu P.
Godhani, Dinesh R.
Lakhmapurkar, Jayendra
Dave, Bharti P.
Powiązania:
https://bibliotekanauki.pl/articles/1030123.pdf
Data publikacji:
2020
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Estuary water
Nutrients
Physico-chemical parameters
Principal component analysis
Tidal variation
Opis:
In the present study, the four estuaries were selected from the South Gujarat region to appraise the impact of industrial pollution in the estuarine water samples. The study focused on the tidal variation of nutrients, which disclosed that concentrations of NO2–N, NO3–N, NH4–N, TN, and reactive silicates were higher in low-tide whereas pH, salinity, and dissolved oxygen were higher in high-tide water samples. The results of high BOD and low DO expose the anthropogenic inputs in these estuaries during the low-tide. The results of physico-chemical and nutrients parameters of water showed that the pollution level is strongly influenced by tidal and seasonal changes. Pearson’s correlation matrix and principal component analysis (PCA) are applied to a hydrological and hydrographical dataset for finding the spatial-temporal variation during the tidal difference. This study suggested that there is an impact of industrial pollution and anthropogenic inputs on the estuarine water of the study area.
Źródło:
World Scientific News; 2020, 143; 79-102
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trace elements in scalp hair of leukaemia patients
Autorzy:
Khuder, A.
Bakir, M. A.
Hasan, R.
Mohammad, A.
Habil, K.
Powiązania:
https://bibliotekanauki.pl/articles/971518.pdf
Data publikacji:
2014
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
leukaemia
principal component analysis
scalp hair
U-test
X-ray fluorescence
Opis:
The aim of this study was to determine the concentration of Fe, Ni, Cu, Zn and Pb in scalp hair of leukaemia patients and healthy volunteers, using the optimised XRF method. Leukaemia hair samples were classifi ed corresponding to type, growth and age of the participants. The results showed that the studied trace elements (TEs) in both of leukaemia and control groups were positively skewed. In comparison with the control group, lower Fe, Cu, Zn and Pb and higher of Ni medians were found in all studied leukaemia patients. The median rank obtained by Mann–Whitney U-test revealed insignifi cant differences between the leukaemia patients subgroups and the controls. An exact probability (α < 0.05) associated with the U-test showed signifi cant differences between medians in leukaemia patients and controls groups for Pb (lymphatic/control, acute/control), Cu (lymphatic/control, chronic/control), Ni (lymphatic/control, chronic/control) and Fe (chronic/control). Very strong positive and negative correlations (r > 0.70) in the scalp hair of control group were observed between Ni/Fe-Ni, Cu/Fe-Cu, Zn/Fe-Zn, Pb/Fe-Pb, Cu/Ni-Zn/Ni, Cu/Ni-Pb/Ni, Zn/Ni-Pb/Ni, Zn/Fe-Zn/Cu, Pb/Ni-Ni and Ni/Fe-Pb/Ni, whereas only very strong positive ratios in the scalp hair of leukaemia patients group were observed between Ni/Fe-Ni, Cu/Fe-Cu, Zn/Fe-Zn and Pb/Fe-Pb, all correlations were signifi cant at p < 0.05. Other strong and signifi cant correlations were also observed in scalp hair of both groups. Signifi cant differences between grouping of studied TEs in all classifi ed leukaemia groups and controls were found using principal component analysis (PCA). The results of PCA confi rmed that the type and the growth of leukaemia factors were more important in element loading than the age factor.
Źródło:
Nukleonika; 2014, 59, 3; 111-120
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Estimating independent components by mapping onto an orthogonal manifold
Autorzy:
Fiori, S.
Powiązania:
https://bibliotekanauki.pl/articles/1933183.pdf
Data publikacji:
2008
Wydawca:
Politechnika Gdańska
Tematy:
independent component analysis
ICA
orthogonal group of matrices
mappings onto manifolds
Opis:
Algorithms for independent component analysis (ICA) based on information-theoretic criteria optimization over differential manifolds have been devised over the last few years. The principles informing their design lead to various classes of learning rules, including the fixed-point and the geodesic-based ones. Such learning algorithms mainly differ by the way in which single learning steps are effected in the neural system's parameter space, i. e. by the action that a connection variable is moved by in the parameter space toward the optimal connection pattern. In the present paper, we introduce a new class of learning algorithms by recalling from the literature on differential geometry the concept of mapping onto manifolds, which provides a general way of acting upon a neural system's connection variable in order to optimize the learning criteria. The numerical behavior of the introduced learning algorithms is illustrated and compared with experiments carried out on mixtures of statistically-independent signals.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2008, 12, 1-2; 105-120
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Factors of the development of organic farming in Poland at the voivodship level
Autorzy:
Nowak, Ewa
Jadczyszyn, Jan
Powiązania:
https://bibliotekanauki.pl/articles/2148092.pdf
Data publikacji:
2020-12-30
Wydawca:
Instytut Uprawy Nawożenia i Gleboznawstwa – Państwowy Instytut Badawczy
Tematy:
organic farming
Rural Development Program
Principal component analysis – PCA
voivodships
Polska
Opis:
The purpose of the research based on the data from the Report on the state of organic farming in Poland in 2015–2016 and environmental conditions, was to determine the impact of natural and economic factors and subsidies from EU programs on the level of organic production and to better understand the diver-sity of the spatial structure of organic farming within the system of provinces (voivodships). Nineteen structural, socio-economic and financial features, and 3 environmental features that charac-terize the quality of agricultural production and forms of nature protection for 16 voivodships, were used as assessment criteria.Principal component analysis allowed the basic factors of diver-sification to be discovered of the set of voivodships contained in the hidden structure defined by the features adopted for analysis. Homogeneous groups – organic farming types by voivodships were distinguished using the k-means method.The comparative analysis allowed the connections between the structure of organic farming and its place in voivodships to be highlighted in connection with support for organic farming, the number of producers of organic agricultural products, production of feed on arable land, production of cereals and vegetables. The location of organic farms is related to the occurrence of Natura 2000 areas. The first type includes two voivodships, Zachodnio-pomorskie and Warmińsko-Mazurskie – with the highest level of development of organic farming. In the second type, the fol-lowing voivodships were concentrated: Lubelskie, Łódzkie, Ma-zowieckie, Podlaskie and Świętokrzyskie, with a high level of or-ganic farming, where farms smaller in area, that focus on fruit and vegetable production are the predominant type. In the third type, the following voivodships were located in the region of western Poland: Pomorskie and Wielkopolskie with a medium level of organic farming and very diverse in characteristics, including the largest and smaller organic farms with a low level of fruit and vegetable production. The fourth type includes the Małopolskie and Podkarpackie voivodships with a very small farm area and a small number of producers. In the fifth type with the least developed organic farming with a small number of producers and low fruit and vegetable production, three voivodships focused on the average farm area: Śląskie, Opolskie and Kujawsko-Pomorskie.
Źródło:
Polish Journal of Agronomy; 2020, 43; 43-46
2081-2787
Pojawia się w:
Polish Journal of Agronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fault diagnosis of rotating machines using vibration and bearing temperature measurements
Autorzy:
Nembhard, A. D.
Sinha, J. K.
Pinkerton, A. J.
Elbhbah, K.
Powiązania:
https://bibliotekanauki.pl/articles/328481.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
Tematy:
vibration monitoring
condition monitoring
rotating machinery
fault diagnosis
principal component analysis
Opis:
Acquisition and subsequent processing of vibration data for fault diagnosis of rotating machinery with multiple bearings, such as Turbo-generator (TG) sets, can be quite involved, as data are usually required in three mutually perpendicular directions for reliable diagnosis. Consequently, the task of diagnosing faults on such systems may be daunting for even an experienced analyst. Hence, the current study aims to develop a simplified fault diagnosis (FD) method that uses just a single vibration and a single temperature sensor on each bearing. Initial trials on an experimental rotating rig indicate that supplementing vibration data with temperature measurements gave improved FD when compared with FD using vibration data alone. Observations made from the initial trials are presented in this paper.
Źródło:
Diagnostyka; 2013, 14, 3; 45-51
1641-6414
2449-5220
Pojawia się w:
Diagnostyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment of the influence of soil properties on 137Cs accumulation in Of horizon in forest soils
Autorzy:
Ziembik, Z.
Dołhańczuk-Śródka, A.
Wacławek, M.
Powiązania:
https://bibliotekanauki.pl/articles/148398.pdf
Data publikacji:
2010
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
137Cs
forest soil
physicochemical parameters
cluster analysis (CA)
principal component analysis (PCA)
Opis:
The work focuses on assessment of soil physicochemical parameters influence on 137Cs accumulation in Of soil horizon. Besides organic matter content and pH, the parameters related to sorption properties and mobile ions concentration were considered. The data were transformed using Box-Cox formula. To find mutual relationships between variables cluster analysis (CA) and principal components analysis (PCA) were used. It was found that the transformed physicochemical parameters in Of horizon are more or less related with each other but no linear or nearly linear relationships between 137Cs activity and physicochemical parameters were found.
Źródło:
Nukleonika; 2010, 55, 2; 205-212
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The North Sea Bicycle Race ECG project : time-domain analysis
Autorzy:
Długosz, D.
Eftestøl, T.
Królak, A.
Wiktorski, T.
Ørn, S.
Powiązania:
https://bibliotekanauki.pl/articles/384850.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Tematy:
ECG
principal Component Analysis
silhouette analysis
clustering
EKG
analiza głównych składowych
grupowanie
klastering
Opis:
Analysis of electrocardiogram and heart rate provides useful information about health condition of a patient. The North Sea Bicycle Race is an annual cycling competition in Norway. Examination of ECG recordings collected from participants of this race may allow defining and evaluating the relationship between physical endurance exercises and heart electrophysiology. Parameters reflecting potentially alarming deviations are to be identified in this study. This paper presents results of a time-domain analysis of ECG data collected in 2014, implementing K-Means clustering. A double stage analysis strategy, aimed at producing hierarchical clusters, is proposed. The first phase allows rough separation of data. Second stage is applied to reveal internal structure of the majority clusters. In both steps, discrepancies driving the separation could stem from three sources. Firstly, they could be signs of abnormalities in electrical activity of the heart. Secondly, they may allow discriminating between natural groups of participants – according to sex, age, physical fitness. Finally, some deviations could result from faults in data extraction, therefore serving in evaluation of the parameters. The clusters were defined predominantly by combinations of features: heartbeat signals correlation, P-wave shape, and RR intervals; none of the features alone was discriminative for all the clusters.
Źródło:
Journal of Automation Mobile Robotics and Intelligent Systems; 2018, 12, 1; 23-32
1897-8649
2080-2145
Pojawia się w:
Journal of Automation Mobile Robotics and Intelligent Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adult Participation in Evening Secondary Schools: The Findings of Empirical Research in the Greek Islands
Autorzy:
Papadimitriou, Achilleas
Powiązania:
https://bibliotekanauki.pl/articles/28409259.pdf
Data publikacji:
2023
Wydawca:
Uniwersytet Dolnośląski DSW. Wydawnictwo Naukowe DSW
Tematy:
adult participation
evening schools
Greek islands
quantitative research
principal component analysis
Opis:
The study of adult participation in education and the examination of the factors that influence their final decision is one of the most critical issues in the field. This article summarises the findings of empirical research on adult engagement in evening schools in Greece, with an emphasis on evening schools in the Greek islands. Evening schools started in Greece around 60 years ago. These schools, now part of the secondary education system, are primarily aimed towards those who work during the day (mostly adults). Their goal is to provide the opportunity for adults who, for some reason, interrupted their studies in Gymnasium (lower secondary/middle school) or Lyceum (upper secondary/high school) to complete it. There has never been a study on residents of Greek islands who participate in educational programmes of this nature. The presented research investigates factors that impact adult participation in all evening schools administratively situated in Greek islands. Between February and May 2022, 268 adult students participated in the study by completing a survey questionnaire that was quantitatively evaluated using SPSSs. The sample comes from all the islands where evening Lyceums operate. To determine the elements that influence participation, the data was submitted to component analysis using the Principal Component Analysis (PCA) approach. Four of the discovered factors are deemed critical (self-assessment, attitudes towards education, educational perspective and expectations), while others seem somewhat relevant and have a role.
Źródło:
Teraźniejszość – Człowiek – Edukacja; 2023, 25, 1(93); 9-32
1505-8808
2450-3428
Pojawia się w:
Teraźniejszość – Człowiek – Edukacja
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of modern methods for increasing and managing the financial prosperity of businesses in the context of performance: a case study of the tourism sector in Slovakia
Autorzy:
Onuferová, Erika
Čabinová, Veronika
Dzurov Vargová, Tünde
Powiązania:
https://bibliotekanauki.pl/articles/19233492.pdf
Data publikacji:
2020
Wydawca:
Instytut Badań Gospodarczych
Tematy:
business performance
modern methods
performance benchmarking
travel agencies
Principal Component Analysis
Opis:
Research background: In the context of constantly changing business environment, the financial sector is focusing on new trends in financial management systems. Nowadays, there is a need to achieve long-term financial growth, so financial managers try to develop new models for managing and improving the financial performance of businesses in economic practice. Purpose of the article: This article aims to determine the financial performance of travel agencies by applying modern business performance evaluation methods in order to create a performance portfolio (ranking) for the years 2013-2017, subsequently to reveal the concordance rate of order of the selected business entities by comparing applied financial methods in the context of performance benchmarking. The research question is as follows: Does the multidimensional PCA method in the form of the performance portfolio of travel agencies provide similar financial results compared to the EVA indicator? Methods: For measuring the financial performance of businesses, the method of Principal Component Analysis (PCA) and the indicator Economic Value Added (EVA) were chosen. Spearman's rank-order correlation was applied in order to reveal the concordance rate of the analyzed travel agencies. Findings & Value added: The results indicate that by applying the PCA method, 6 key performance factors can be identified. Moreover, the findings revealed that the assessment of travel agencies using the PCA method and EVA indicator did not lead to the same financial results. Individual financial methods identified a different number of strong-performing and inefficient business entities. In this backdrop, we concluded that the business performance measurement based on the PCA method is not a suitable alternative to measuring performance using the EVA indicator.
Źródło:
Oeconomia Copernicana; 2020, 11, 1; 95-116
2083-1277
Pojawia się w:
Oeconomia Copernicana
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Forecasting of subjective comfort in tram using ordinal logistic regression and manifold learning
Autorzy:
Pietraszek, J.
Grzegożek, W.
Szczygieł, J.
Powiązania:
https://bibliotekanauki.pl/articles/246634.pdf
Data publikacji:
2012
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
rail transport
vibrations
ordinal logistic regression
principal component analysis
manifold learning
Opis:
Comfort in a vehicle has a very important role to play as one of the most important dynamic performance characteristics of rail vehicles. It is the factor of ever-increasing importance, even creating a specialized branch of engineering associated with relation between human limitations and designing of machines: human–factors engineering. The vibration is known to be a major factor that affects and deteriorates ride comfort. For evaluating ride comfort in rail vehicles, there have been developed methods resulting in the creation of many standards and multiple criteria used and even standardized in different countries. One of the authors, J. Szczygieł designed and performed a passive experiment to collect data describing physical conditions of ride and associated subjective assessments of comfort. Panel of fourteen people during the tram ride made synchronous subjective assessments of comfort, assessing it on a discrete ordinal scale of 0 to 5, using electronic panels connected to the computer. At the same time computer through sensors recorded values of acceleration in three perpendicular axes. It made possible to correlate the fuzzy subjective evaluations with objective physical measurements. Because of the discrete type of fuzzy ratings of comfort, natural way of modelling is the ordinal logistic regression. The classic form of the ordinal logistic regression assumes that in the space of explanatory factors there are parallel activation hyper-planes slightly disturbed by unknown or uncontrolled noise factors. In fact, the assumption of linearity is a very strong idealization and leads to considerable misclassifications. The original space of explanatory factors is 11-dimensional with ten continuous dimensions and one discrete. Then the multivariate method, principal component analysis (PCA), was used to identify principal components, which are responsible most to the variability of the studied set. The scree plot was used to identify the number of significant PCA factors. The use of PCA revealed that the area occupied by the data set is approximately 6-dimensional. However, the dimensionality reduction of explanatory variables set did not lead to better forecasting accuracy. A more subtle analysis involving discretization techniques showed that activation hyperplanes are highly curved in the six-dimensional area identified by PCA but their dimensionality is much lower. The details of the procedure are described in the article. The article conclusion is that is necessary to introduce curvilinear coordinate system embedded into the shapes of activation hyper-planes to obtain better classification.
Źródło:
Journal of KONES; 2012, 19, 2; 403-409
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of evaluation algorithm for port logistics park based on PCA-SVM model
Autorzy:
Hu, B.
Powiązania:
https://bibliotekanauki.pl/articles/260528.pdf
Data publikacji:
2018
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
port logistics demand
support vector machine
principal component analysis
economic hinterland
Opis:
To predict the logistics needs of the port, an evaluation algorithm for the port logistics park based on the PCASVM model was proposed. First, a quantitative indicator set for port logistics demand analysis was established. Then, based on the grey correlation analysis method, the specific indicator set of port logistics demand analysis was selected. The advantages of both principal component analysis and support vector machine algorithms were combined. The PCA-SVM model was constructed as a predictive model of the port logistics demand scale. The empirical analysis was conducted. Finally, from the perspective of the structure, demand, flow pattern and scale of port logistics demand, the future logistics demand of Shenzhen port was analysed. Through sensitivity analysis, the main influencing factors were found out, and the future development proposals of Shenzhen port were put forward. The results showed that the port throughput of Shenzhen City in 2016 was 21,328,200 tons. Compared with the previous year, it decreased by about 1.74 %. In summary, the PCA-SVM model accurately predicts the logistics needs of the port.
Źródło:
Polish Maritime Research; 2018, S 3; 29-35
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
ICA-based Single Channel Audio Separation: New Bases and Measures of Distance
Autorzy:
Mika, D.
Kleczkowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/177414.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
audio unmixing
blind signal separation
independent component analysis
measures of distance
Opis:
Independent Component Analysis (ICA) can be used for single channel audio separation, if a mixed signal is transformed into time-frequency domain and the resulting matrix of magnitude coefficients is processed by ICA. Previous works used only frequency (spectral) vectors and Kullback-Leibler distance measure for this task. New decomposition bases are proposed: time vectors and time-frequency components. The applicability of several different measures of distance of components are analysed. An algorithm for clustering of components is presented. It was tested on mixes of two and three sounds. The perceptual quality of separation obtained with the measures of distance proposed was evaluated by listening tests, indicating “beta” and “correlation” measures as the most appropriate. The “Euclidean” distance is shown to be appropriate for sounds with varying amplitudes. The perceptual effect of the amount of variance used was also evaluated.
Źródło:
Archives of Acoustics; 2011, 36, 2; 311-331
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Interrelationship and Determining Factors of Water Quality Dynamics in Whiteleg Shrimp Ponds in Tropical Eco-Green Aquaculture System
Autorzy:
Musa, Muhammad
Mahmudi, Mohammad
Arsad, Sulastri
Lusiana, Evellin Dewi
Sunadji
Wardana, Wisnu Angga
Ompusunggu, Magdalena Florensia
Damayanti, Dhea Novita
Powiązania:
https://bibliotekanauki.pl/articles/2202326.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
aquaculture wastewater
intensive system
Litopenaeus vannamei
mangrove
PCA
principal component analysis
Opis:
Whiteleg shrimp (Litopenaeus vannamei) farming is a major activity in the coastal areas of many tropical countries. To meet the demand in this market, the culture system has expanded using intensive technology, which has resulted in the emission of effluents that threaten the surrounding aquatic ecosystem. Therefore, proper aquaculture management is needed to ensure both economic and ecological benefits. This led to the emergence of eco-green aquaculture. Water quality monitoring is a critical part of aquaculture management and when performed regularly, it yields a large and complex dataset. In this study, the authors aimed to analyse the dynamics of water quality characteristics and the relationships between these variables in whiteleg shrimp ponds in a tropical eco-green aquaculture system from 2020 to 2022. Since the data includes nine parameters and is quite complex, the principal component analysis (PCA) approach was used. This method enables to identify the factors that determine water quality, which will help ensure effective and efficient aquaculture management. Consequently, the water quality variables in the studied area were reduced to five dimensions and salinity, ammonia, and pH were found to be the key factors responsible for the changes in water quality characteristics. Hence, these variables should be the focus of farming management systems.
Źródło:
Journal of Ecological Engineering; 2023, 24, 1; 19--27
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Epistemic Words on the Confidence Scale
Autorzy:
Byalyk, Vasyl Dmytrovych
Nizhnik, Liudmyla Ivanivna
Powiązania:
https://bibliotekanauki.pl/articles/2231494.pdf
Data publikacji:
2022-10-06
Wydawca:
Komisja Nauk Filologicznych Polskiej Akademii Nauk, Oddział we Wrocławiu
Tematy:
epistemic words
modal strength
level of confidence
confidence scale
component analysis
Opis:
The article examines a group of 107 epistemic words in order to determine their integral and differential semes and place them on the confidence scale. The relevance of the study is conditioned by the interest in studying the stance of a speaker’s utterance. The article analyses the notion of epistemic words, their linguistic and non-linguistic properties. As a result of definition and semantic analyses of epistemic words, epistemic words with high, medium and low modal strength were singled out. Such a categorization is possible, because epistemic words have the same integral semes but various differential semes. Epistemic words have a scalar nature and the level of their modal strength reflects the speaker’s commitment to the utterance that ranges from confidence to uncertainty.
Źródło:
Academic Journal of Modern Philology; 2022, 15; 107-115
2299-7164
2353-3218
Pojawia się w:
Academic Journal of Modern Philology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Infrasound Signal Classification Based on ICA and SVM
Autorzy:
Lu, Quanbo
Wang, Meng
Li, Mei
Powiązania:
https://bibliotekanauki.pl/articles/31339863.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
independent component analysis
fast Fourier transform
support vector machine
infrasound signal
Opis:
A diagnostic technique based on independent component analysis (ICA), fast Fourier transform (FFT), and support vector machine (SVM) is suggested for effectively extracting signal features in infrasound signal monitoring. Firstly, ICA is proposed to separate the source signals of mixed infrasound sources. Secondly, FFT is used to obtain the feature vectors of infrasound signals. Finally, SVM is used to classify the extracted feature vectors. The approach integrates the advantages of ICA in signal separation and FFT to extract the feature vectors. An experiment is conducted to verify the benefits of the proposed approach. The experiment results demonstrate that the classification accuracy is above 98.52% and the run time is only 2.1 seconds. Therefore, the proposed strategy is beneficial in enhancing geophysical monitoring performance.
Źródło:
Archives of Acoustics; 2023, 48, 3; 191-199
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analiza porównawcza efektywności metod redukcji zmiennych - analiza składowych głównych i analiza czynnikowa
Comparative Analysis of Effectiveness of the Methods for Reduction of Variables - Principal Component Analysis and Factor Analysis
Autorzy:
Czopek, Anna
Powiązania:
https://bibliotekanauki.pl/articles/589975.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Ekonomiczny w Katowicach
Tematy:
Analiza czynnikowa
Analiza porównawcza
Analizy głównych komponentów
Comparative analysis
Factor analysis
Principal Component Analysis
Opis:
Principal component analysis and factor analysis are the two most popular methods that allow to bring a large number of studied variables to a much smaller number of mutually independent principal components or factors. New variables (principal components or factors) retain a relatively large part of the information contained in the original variables, while each of them is a carrier of other substantive content. Both of these methods of reduction of the variables are often used, because too many pending attributes increases the range of the difficulty of interpretation. The main reason of undertaking the project is an attempt to show, that the abovementioned methods, although they are very similar, cannot be indentified. Despite the fact, that in both cases eigenvalues are calculated, factor loadings, etc., but still there are differences in the way of action, about which it must be remembered. So the usage of these names the variables are unacceptable. The article consists of three parts. The first and second chapter are devoted, respectively, to the analysis of the principal components and factor analysis, where a short characterization of these methods had been made. In the third chapter, on the basis of an empirical example, we compared the effectiveness of the principal components analysis and factor analysis.
Źródło:
Studia Ekonomiczne; 2013, 132; 7-23
2083-8611
Pojawia się w:
Studia Ekonomiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparison of the beef prices in selected countries of the European Union
Autorzy:
Jaworski, Stanisław
Powiązania:
https://bibliotekanauki.pl/articles/453098.pdf
Data publikacji:
2012
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Katedra Ekonometrii i Statystyki
Tematy:
B-splines basis system
functional principal component analysis
functional analysis of variance
permutation tests
Opis:
Functional data analysis is used to examine beef price differences in selected countries of the European Union from 2006 to 2011. The prices are modeled as functional observations. The analysis is conducted in three steps relating to three kinds of functional data analysis. First the observations are smoothed with roughness penalty. Then functional principal analysis is applied. Finally functional analysis of variance is used to reveal significant difference between two given groups of countries.
Źródło:
Metody Ilościowe w Badaniach Ekonomicznych; 2012, 13, 2; 31-39
2082-792X
Pojawia się w:
Metody Ilościowe w Badaniach Ekonomicznych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Intelligent Prediction Model of the Thermal and Moisture Comfort of the Skin-Tight Garment
Autorzy:
Cheng, Pengpeng
Wang, Jianping
Zeng, Xianyi
Bruniaux, Pascal
Chen, Daoling
Powiązania:
https://bibliotekanauki.pl/articles/2056304.pdf
Data publikacji:
2022
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
sportswear tights
thermal comfort
moisture comfort
principal component analysis
intelligent prediction model
Opis:
In order to improve the efficiency and accuracy of predicting the thermal and moisture comfort of skin-tight clothing (also called skin-tight underwear), principal component analysis (PCA) is used to reduce the dimensions of related variables and eliminate the multicollinearity relationship among variables. Then, the optimized variables are used as the input parameters of the coupled intelligent model of the genetic algorithm (GA) and back propagation (BP) neural network, and the thermal and moisture comfort of different tights (tight tops and tight trousers) under different sports conditions is analysed. At the same time, in order to verify the superiority of the genetic algorithm and BP neural network intelligent model, the prediction results of GA-BP, PCA-BP and BP are compared with this model. The results show that principal component analysis (PCA) improves the accuracy and adaptability of the GA-BP neural network in predicting thermal and humidity comfort. The forecasting effect of the PCA-GA-BP neural network is obviously better than that of the GA-BP, PCA-BP, BP model, which can accurately predict the thermal and moisture comfort of tight-fitting sportswear. The model has better forecasting accuracy and a simpler structure.
Źródło:
Fibres & Textiles in Eastern Europe; 2022, 1 (151); 50--58
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Music Recommendation System
Autorzy:
Hoffmann, P.
Kaczmarek, A.
Spaleniak, P.
Kostek, B.
Powiązania:
https://bibliotekanauki.pl/articles/308747.pdf
Data publikacji:
2014
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
feature vectors
music classification
music information retrieval
music parametrization
principal component analysis
Opis:
The paper focuses on optimization vector content feature for the music recommendation system. For the purpose of experiments a database is created consisting of excerpts of music files. They are assigned to 22 classes corresponding to different music genres. Various feature vectors based on low-level signal descriptors are tested and then optimized using correlation analysis and Principal Component Analysis (PCA). Results of the experiments are shown for the variety of feature vectors. Also, a music recommendation system is presented along with its main user interfaces.
Źródło:
Journal of Telecommunications and Information Technology; 2014, 2; 59-69
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wielocechowa analiza różnorodności fenotypowej mieszańców ziemniaka uzyskanych z krzyżowań tetraploid × diploid
Multivariate analysis of phenotypic diversity in the tetraploid × diploid hybrid progenies of potatoes
Autorzy:
Domański, Leszek
Mańkowski, Dariusz R.
Flis, Bogdan
Jakuczun, Henryka
Zimnoch-Guzowska, Ewa
Powiązania:
https://bibliotekanauki.pl/articles/2198318.pdf
Data publikacji:
2012-06-28
Wydawca:
Instytut Hodowli i Aklimatyzacji Roślin
Tematy:
analiza składowych głównych
zmienność wielocechowa
ziemniak
multivariable variation
potato
principal component analysis
Opis:
Osiemdziesiąt rodów ziemniaka uzyskanych z czterech interploidalnych krzyżowań 4x-2x zostało ocenione na 12 cech użytkowych, w tym morfologii bulw, w Instytucie Hodowli i Aklimatyzacji Roślin, Oddział Młochów w latach 2008–2009. Celem badań była ocena genotypowej różnorodności wśród rodów ziemniaka i uzyskanie wglądu w strukturę wielocechowej zmienności. Analiza składowych głównych (PCA) wyodrębniła pięć składowych głównych, które wyjaśniały 78,4% łącznej wariancji wśród rodów ziemniaka. Wykazana przez analizę PCA genotypowa różnorodność potomstwa 4x-2x daje szansę na wyselekcjonowanie wartościowych tetraploidalnych rodów zarówno na jadalny, jak i przetwórczy kierunek użytkowania. Spośród wyodrębnionych pięciu składowych głównych pierwsze trzy były najważniejsze. Pierwsza składowa (29,9% zmienności) była głównie skorelowana z regularnością kształtu, głębokością oczek i ciemnieniem enzymatycznym. Druga składowa, tłumacząca 16% łącznej zmienności była dodatnio skorelowana z plonem bulw, średnią masą bulwy i spłaszczeniem bulw. Trzecia składowa, wyjaśniająca 13,2% łącznej zmienności była pozytywnie skorelowana z zawartością skrobi i barwą chipsów.
Eighty potato clones derived from interploid crosses 4x-2x were evaluated for 12 tuber morphological and agronomic traits at the Plant Breeding and Acclimatization Institute — National Research Institute, Research Center Młochów during 2008–2009. The objective of the research was to assess the genotypic diversity among potato clones and to gain insight into the structure of multivariable variation. The principal component analysis (PCA) distinguished five principle components which explained 78.4% of the total variance among potato clones. The demonstrated genotypic diversity of 4x-2x progenies gives the chance for selecting valuable tetraploid clones for both table and processing use. Out of five PCs, the first three were the most important. The first PC (29.9% of total variance) was mostly correlated with shape regularity, depth of eyes and enzymatic browning. The second PC, that explained 16.2% of the total variance, was positively correlated with tuber yield, mean tuber weight and tuber flatness. The third PC explaining 13.2% of the total variance was positively correlated with starch content and chip colour.
Źródło:
Biuletyn Instytutu Hodowli i Aklimatyzacji Roślin; 2012, 264; 189-194
0373-7837
2657-8913
Pojawia się w:
Biuletyn Instytutu Hodowli i Aklimatyzacji Roślin
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Multivariate Technique to Develop Hybrid Water Quality Index of the Bengawan Solo River, Indonesia
Autorzy:
Lusiana, Evellin Dewi
Mahmudi, Mohammad
Hutahaean, Sarah Mega
Darmawan, Arief
Buwono, Nanik Retno
Arsad, Sulastri
Musa, Muhammad
Powiązania:
https://bibliotekanauki.pl/articles/2026733.pdf
Data publikacji:
2022
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
principal component analysis
WQI
water quality index
variable selection
water quality assessment
Opis:
Surface water resource, such as river, is constantly contaminated by domestic and industrial pollutants. In order to properly manage the water resource, a composite index for water quality assessment, such as water quality index (WQI), has been designed to monitor and evaluate the properties of surface water. However, this index is quite subjective in terms of determination of relative weights. A principal component analysis (PCA) can be used to reduce the dimension and subjectivity of water quality variables. The purpose of this study was to implement the use of hybrid PCA and WQI methods to assess and monitor the water quality of the Bengawan Solo River, which is located in Java Island, Indonesia. The result suggested that COD, BOD, TSS, TDS, nitrate, nitrite, and ammonia were the main factors that determine water quality of the Bengawan Solo River. Furthermore, it was revealed that most samples from the river showed water quality status as slightly polluted. In addition to this, the seasonal variation of the PCWI values indicated a significant increase of water pollution in the Bengawan Solo River per year.
Źródło:
Journal of Ecological Engineering; 2022, 23, 2; 123-131
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Feature vector or time-series – comparison of gestures representations in automatic gesture recognition systems
Autorzy:
Barczewska, K.
Wójtowicz, W.
Moszkowski, T.
Powiązania:
https://bibliotekanauki.pl/articles/115720.pdf
Data publikacji:
2015
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
principal component analysis (PCA)
independent component analysis (ICA)
neural networks
sign language
automatic recognition
analiza składowych głównych (PCA)
analiza składowych niezależnych (ICA)
sieci neuronowe
język migowy
automatyczne rozpoznawanie
Opis:
In this paper, we performed recognition of isolated sign language gestures - obtained from Australian Sign Language Database (AUSLAN) – using statistics to reduce dimensionality and neural networks to recognize patterns. We designated a set of 70 signal features to represent each gesture as a feature vector instead of a time series, used principal component analysis (PCA) and independent component analysis (ICA) to reduce dimensionality and indicate the features most relevant for gesture detection. To classify the vectors a feedforward neural network was used. The resulting accuracy of detection ranged between 61 to 87%.
Źródło:
Challenges of Modern Technology; 2015, 6, 1; 1-5
2082-2863
2353-4419
Pojawia się w:
Challenges of Modern Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Forecast of prices and volatility on the day ahead market
Autorzy:
Ganczarek-Gamrot, Alicja
Powiązania:
https://bibliotekanauki.pl/articles/425278.pdf
Data publikacji:
2013
Wydawca:
Wydawnictwo Uniwersytetu Ekonomicznego we Wrocławiu
Tematy:
principal component analysis (PCA)
SARIMA model
DCC model
Value-at- -Risk
portfolio
Opis:
The subject of this paper is the forecast of prices and volatility on the Day Ahead Market (DAM). The analysis was made for two portfolios of four contracts from 30.03.2009 to 28.10.2011 for two fixings on DAM. Four out of 24 contracts noted on DAM were chosen by PCA. Prices were forecast by the SARIMA models incorporating autocorrelation and seasonality. Value-at-Risk calculated through the DCC model was used to forecast volatility. These models describe well the prices and volatility on the DAM and may be used for forecasting purposes. Prices on fixing 2 are characterized by higher volatility than prices on fixing 1.
Źródło:
Econometrics. Ekonometria. Advances in Applied Data Analytics; 2013, 1(39); 111-120
1507-3866
Pojawia się w:
Econometrics. Ekonometria. Advances in Applied Data Analytics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Major, minor, and trace elements in whole blood of patients with different leukemia patterns
Autorzy:
Khuder, A.
Bakir, M. A.
Solaiman, A.
Issa, H.
Habil, K.
Mohammad, A.
Powiązania:
https://bibliotekanauki.pl/articles/146612.pdf
Data publikacji:
2012
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
leukemia
principal component analysis
Student's t test
whole blood
X-ray fluorescence
Opis:
The elemental sensitivity method for X-ray fluorescence analysis was applied to determine S, Cl, K, Ca, Fe, Cu, Zn, Br, and Rb in the whole blood of leukemia patients and healthy volunteers. Leukemia samples were classified according to type, growth, and age of participants. Student’s t-test results showed that, the mean concentration of the studied elements was significantly lower in leukemia patients than that in controls. Strong mutual correlations (r greather than 0.50) in the whole blood of leukemia patients were observed between S-Ca, K-Fe, K-Ca, Fe-Zn, K-Zn, K-Rb, Fe-Rb, Zn-Rb, S-Cl, S-K, Ca-Fe, Cl-Ca, and Ca-Rb; whereas, S-K, S-Ca, S-Cl, Cl-K, Cl-Ca, Fe-Zn, Zn-Rb, Fe-Rb, K-Fe, and Zn-Br exhibited strong relationships (r greather than 0.50) in the whole blood of controls, all were significant at p less than 0.05. Significant differences between grouping of studied elements in the control group and all classified leukemia groups, except younger age-group, were obtained using principal component analysis. The study indicated appreciably different patterns of element distribution and mutual relationships in the whole blood of leukemia patients in comparison with controls.
Źródło:
Nukleonika; 2012, 57, 3; 389-399
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Forecasting Yield Curves in an Adaptive Framework
Autorzy:
Chen, Ying
Li, Bo
Powiązania:
https://bibliotekanauki.pl/articles/483285.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
interest rates
functional principal component analysis
local parametric model
Nelson-Siegel model
Opis:
Forecasting yield curves with regime switches is important in academia and financial industry. As the number of interest rate maturities increases, it poses difficulties in estimating parameters due to the curse of dimensionality. To deal with such a feature, factor models have been developed. However, the existing approaches are restrictive and largely based on the stationarity assumption of the factors. This inaccuracy creates non-ignorable financial risks, especially when the market is volatile. In this paper, a new methodology is proposed to adaptively forecast yield curves. Specifically, functional principal component analysis (FPCA) is used to extract factors capable of representing the features of yield curves. The local AR(1) model with time-dependent parameters is used to forecast each factor. Simulation and empirical studies reveal the superiority of this method over its natural competitor, the dynamic Nelson-Siegel (DNS) model. For the yield curves of the U.S. and China, the adaptive method provides more accurate 6- and 12-month ahead forecasts.
Źródło:
Central European Journal of Economic Modelling and Econometrics; 2011, 3, 4; 237-259
2080-0886
2080-119X
Pojawia się w:
Central European Journal of Economic Modelling and Econometrics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Robustness study of the road profile estimation technique under uncertainty
Autorzy:
Ben Jdidia, Anoire
Ben Hassen, Dorra
Hentati, Taissir
Abbes, Slim
Haddar, Mohamed
Powiązania:
https://bibliotekanauki.pl/articles/2104771.pdf
Data publikacji:
2022
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
Independent Component Analysis (ICA) method
Monte Carlo (MC) method
road profile
estimation
Opis:
This paper studies profile estimation a road. The prediction has been achieved using the Independent Component Analysis Method (ICA). The vehicle dynamic responses were cal- culated for different road profiles which were defined using an ISO norm. The robustness of this method was proven by implementing the stochastic Monte Carlo (MC) technique in the presence of inevitable uncertainty parameters simultaneously associated with the vehicle mass, spring stiffness and damping for different vehicle speeds and wind values. Convergence was assessed when comparing real profiles to simulated ones. The obtained results prove the efficiency of the ICA in estimating the profile variabilities under uncertainties.
Źródło:
Journal of Theoretical and Applied Mechanics; 2022, 60, 3; 521--533
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Porównanie wybranych statystycznych metod analizy danych hydrogeochemicznych na przykładzie kenozoicznych poziomów wodonośnych w obszarze zlewni Gwdy
Comparison of selected statistical methods of hydrogeochemical data analysis exemplified by Cenozoic aquifers within the Gwda River basin
Autorzy:
Kotowski, T.
Powiązania:
https://bibliotekanauki.pl/articles/2062952.pdf
Data publikacji:
2011
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
hydrogeochemia
analiza skupień
analiza składowych głównych
analiza czynnikowa
hydrogeochemistry
cluster analysis
principal component analysis
factor analysis
Opis:
W pracy zaprezentowano porównanie wybranych metod wnioskowania statystycznego, stosowanych w badaniach hydrogeochemicznych. Metody statystyczne zostały zastosowane w celu wstępnej identyfikacji procesów formowania składu chemicznego wód poziomów mioceńskiego i głębokiego plejstoceńskiego na obszarze zlewni Gwdy. W rezultacie przeprowadzonej analizy skupień otrzymano trzy grupy (skupienia) czynników kształtujących skład chemiczny wód podziemnych. W wyniku analizy składowych głównych i analizy czynnikowej wyróżniono zbiory dwóch czynników kształtujących skład chemiczny wód podziemnych. Wszystkie zastosowane metody okazały się wrażliwe na występowanie anomalii hydrogeochemicznych. Z tego względu, w przypadku analizy skupień i analizy składowych głównych, niemożliwe było dokonanie w pełni poprawnego opisu chemizmu wód podziemnych w obszarze badań. Najlepsze rezultaty osiągnięto przy zastosowaniu analizy czynnikowej. Wyniki analiz statystycznych odniesiono do rezultatów dodatkowych badań: składu izotopowego wody, stężeń siarczanów, trytu oraz badań mikrobiologicznych. Zastosowane metody statystyczne okazały się pomocne, jednakże interpretacja uzyskanych, szczególnie zróżnicowanych danych, jest utrudniona.
Comparison of selected methods of hydrogeochemical statistical analysis is presented in the paper. Statistical methods were applied to initially identify the formation processes of groundwater chemical composition within the Gwda river basin. As a result of a cluster analysis, three cluster sets of factors forming the chemical composition of the groundwater were distinguished. A set of two factors forming the chemical composition of the groundwater was distinguished as a result of a principal component analysis and a factor analysis. All the statistical methods used were found out to be susceptible upon hydrogeochemical anomalies. The observed susceptibility of the cluster analysis and the principal component analysis allowed a fully correct description of the formation of the groundwater chemical composition in the study area. The best results were achieved using the factor analysis, but this method is also susceptible upon the anomaly cases. The results of the statistical analysis were compared with the research results of additional factors such as the isotopic composition of water and concentrations of sulfates and tritium. The statistical methods appeared to be helpful. However, the interpretation of research results without the additional factors is intractable, especially in the case of hydrogeochemical anomalies.
Źródło:
Biuletyn Państwowego Instytutu Geologicznego; 2011, 447; 15--24
0867-6143
Pojawia się w:
Biuletyn Państwowego Instytutu Geologicznego
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Slovak Creativity Index – A PCA Based Approach
Autorzy:
Hudec, Oto
Klasová, Slávka
Powiązania:
https://bibliotekanauki.pl/articles/623791.pdf
Data publikacji:
2016-07-07
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
Slovak creativity index
urbanisation
principal component analysis
R11
C21
A13
Opis:
The article aims at transferring the European Creativity Index (ECI) assessment from the country to regional comparison basis, focusing on the case of Slovakia. The newly created Slovak Creativity Index (SCI) has the power to assess the creativity potential found in the Slovak regions. The Principal Component Analysis has been chosen as an advanced method for establishing a well-designed overall Index and six sub-indices to show differences and variability according to all dimensions of the creative potential. The research also explains several relations between creative performance of the regions by several factors such as urbanisation, cultural environment, human capital and tolerance.
Źródło:
European Spatial Research and Policy; 2016, 23, 1
1231-1952
1896-1525
Pojawia się w:
European Spatial Research and Policy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Biometric watermarking for security enhancement in digital images
Autorzy:
Wójtowicz, W.
Powiązania:
https://bibliotekanauki.pl/articles/115437.pdf
Data publikacji:
2013
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
images security
watermarking technique
discrete wavelet transform (DWT)
biometrics
principal component analysis (PCA)
Opis:
In this paper some preliminary investigation on combination of watermarking technique with biometric data to increase security of digital images in case of medical images is proposed. Performance of watermarking algorithm, based on discrete wavelet transform (DWT) decomposition, that incorporates biometric watermark is elaborated. The frequency domain were chosen as it is proven, that this domain provides better robustness against attacks and leads to less perceptibility of an embedded watermark. To assure confidentiality of patient data their hand geometry features are embedded instead of patient’s name. Proposed system is evaluated by measuring the similarity between embedded and extracted biometric codes.
Źródło:
Challenges of Modern Technology; 2013, 4, 4; 7-11
2082-2863
2353-4419
Pojawia się w:
Challenges of Modern Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electronic nose with polymer-composite sensors for monitoring fungal deterioration of stored rapeseed
Autorzy:
Gancarz, Marek
Wawrzyniak, Jolanta
Gawrysiak-Witulska, Marzena
Wiącek, Dariusz
Nawrocka, Agnieszka
Rusinek, Robert
Powiązania:
https://bibliotekanauki.pl/articles/973040.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
principal component analysis
e-nose
rapeseed
ergosterol
colony forming units
volatile organic compounds
Opis:
Investigations were performed to examine the possibility of using an electronic nose to monitor development of fungal microflora during the first eighteen days of rapeseed storage. The Cyranose 320 device manufactured by Sensigent was used to analyse volatile organic compounds. Each sample of infected material was divided into three parts and the degree of spoilage was measured in three ways: analysis of colony forming units, determination of ergosterol content, and measurement of volatile organic compounds with the e-nose. Principal component analysis was performed on the generated patterns of signals and six groups of different spoilage levels were isolated. An analysis of sensorgrams for a few sensors with a strong signal for each group of rapeseed spoilage was performed. The ratio of the association time to the steady state was calculated. This ratio was different for the low level and the highest level of ergosterol and colony forming units. The results have shown that the e-nose can be a useful tool for quick estimation of the degree of rapeseed spoilage.
Źródło:
International Agrophysics; 2017, 31, 3
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Selection of optimal coal blends in terms of ash fusion temperatures using Support Vector Machine (SVM) classifier - a case study for Polish coals
Autorzy:
Żogała, Alina
Rzychoń, Maciej
Łączny, Jacek M.
Róg, Leokadia
Powiązania:
https://bibliotekanauki.pl/articles/110177.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
coal blends
ash fusion temperature
support vector machine
principal component analysis
machine learning
Opis:
One of the most important criteria for selecting coal for a given technology are the ash Fusion temperatures (AFTs). An effective way to regulate the AFTs so that they meet the criteria for a given industrial application is to form blends of different coals. The values of the AFTs in the blends are nonadditive, therefore they can't be calculated using the weighted average of the blend components. On the other hand, direct determination of ATFs values requires many additional time-consuming and expensive laboratory tests. Therefore, it is important to develop a solution that, in addition to the effective prediction of the values of AFTs, will also enable optimal selection of components of the blend in terms of its key parameters. The aim of the work was to develop an algorithm for the selection of the optimal coal blends in terms of AFTs for given industrial applications. This algorithm uses nonlinear classifying model which was built using machine learning method, support vector machine (SVM). To carry out the training samples of Polish hard coals from different mines of the Upper Silesian Coal Basin were used. The accuracy of the developed model is 92.3%. The results indicate the effectiveness of the proposed solution, which can find practical application in the form of an expert system used in the coal industry. The paper presents the concept of developed IT tool which has been tested for a selected case.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 5; 1311-1322
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
PCA-based approximation of a class of distributed parameter systems: classical vs. neural network approach
Autorzy:
Bartecki, K.
Powiązania:
https://bibliotekanauki.pl/articles/201641.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
distributed parameter system
principal component analysis
artificial neural network
supervised learning
unsupervised learning
Opis:
In this article, an approximation of the spatiotemporal response of a distributed parameter system (DPS) with the use of the principal component analysis (PCA) is considered. Based on a data obtained by the numerical solution of a set of partial differential equations, a PCA-based approximation procedure is performed. It consists in the projection of the original data into the subspace spanned by the eigenvectors of the data covariance matrix, corresponding to its highest eigenvalues. The presented approach is carried out using both the classical PCA method as well as two different neural network structures: two-layer feed-forward network with supervised learning (FF-PCA) and single-layer network with unsupervised, generalized Hebbian learning rule (GHA-PCA). In each case considered, the effect of the approximation model structure represented by the number of eigenvectors (or, in the neural case, units in the network projection layer) on the mean square approximation error of the spatiotemporal response and on the data compression ratio is analysed. As shown in the paper, the best approximation quality is obtained for the classical PCA method as well as for the FF-PCA neural approach. On the other hand, an adaptive learning method for the GHA-PCA network allows to use it in e.g. an on-line identification scheme.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2012, 60, 3; 651-660
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of the principal component analysis of texture features on the classification quality of sponge tissue images
Wpływ analizy głównych składowych cech tekstury na jakość klasyfikacji obrazów tkanki gąbczastej
Autorzy:
Dzierżak, Róża
Powiązania:
https://bibliotekanauki.pl/articles/1841333.pdf
Data publikacji:
2020
Wydawca:
Politechnika Lubelska. Wydawnictwo Politechniki Lubelskiej
Tematy:
principal component analysis
classification
texture analysis
medical imaging
analiza głównych składowych
klasyfikacja
analiza tekstury
obrazowanie medyczne
Opis:
The aim of this article was to determine the effect of principal component analysis on the results of classification of spongy tissue images. Four hundred computed tomography images of the spine (L1 vertebra) were used for the analyses. The images were from fifty healthy patients and fifty patients diagnosed with osteoporosis. The obtained tissue image samples with a size of 50x50 pixels were subjected to texture analysis. As a result, feature descriptors based on a grey level histogram, gradient matrix, RL matrix, event matrix, autoregressive model and wavelet transform were obtained. The results obtained were ranked in importance from the most important to the least important. The first fifty features from the ranking were used for further experiments. The data were subjected to the principal component analysis, which resulted in a set of six new features. Subsequently, both sets (50 and 6 traits) were classified using five different methods: naive Bayesian classifier, multilayer perceptrons, Hoeffding Tree, 1-Nearest Neighbour and Random Forest. The best results were obtained for data on which principal components analysis was performed and classified using 1-Nearest Neighbour. Such an algorithm of procedure allowed to obtain a high value of TPR and PPV parameters, equal to 97.5%. In the case of other classifiers, the use of principal component analysis worsened the results by an average of 2%.
Celem niniejszego artykułu było określenie wpływu analizy głównych składowych na wyniki klasyfikacji obrazów tkanki gąbczastej. Do analiz wykorzystano czterysta obrazów tomografii komputerowej kręgosłupa (kręg L1). Obrazy pochodziły od pięćdziesięciu zdrowych pacjentów oraz pięćdziesięciu pacjentów ze zdiagnozowaną osteoporozą. Uzyskane próbki obrazowe tkanki o wymiarze 50x50 pikseli poddano analizie tekstury. W wyniku tego otrzymano deskryptory cech oparte na histogramie poziomów szarości, macierzy gradientu, macierzy RL, macierzy zdarzeń, modelu autoregresji i transformacie falkowej. Otrzymane wyniki ustawiono w rankingu ważności od najistotniejszej do najmniej ważnej. Pięćdziesiąt pierwszych cech z rankingu wykorzystano do dalszych eksperymentów. Dane zostały poddane analizie głównych składowych wskutek czego uzyskano zbiór sześciu nowych cech. Następnie oba zbiory (50 i 6 cech) zostały poddane klasyfikacji przy użyciu pięciu różnych metod: naiwnego klasyfikatora Bayesa, wielowarstwowych perceptronów, Hoeffding Tree, 1-Nearest Neighbour and Random Forest. Najlepsze wyniki uzyskano dla danych, na których przeprowadzono analizę głównych składowych i poddano klasyfikacji za pomocą 1-Nearest Neighbour. Taki algorytm postępowania pozwolił na uzyskanie wysokiej wartości parametrów TPR oraz PPV, równych 97,5%. W przypadku pozostałych klasyfikatorów zastosowanie analizy głównych składowych pogorszyło wyniki średnio o 2%.
Źródło:
Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska; 2020, 10, 3; 13-16
2083-0157
2391-6761
Pojawia się w:
Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Przenośny analizator diagnostyczny do wykrywania uszkodzeń stojana i wirnika w silnikach indukcyjnych
Portable Diagnostic Analyzer to Detection of the Stator and Rotor Faults in Induction Motors
Autorzy:
Pawlak, M.
Powiązania:
https://bibliotekanauki.pl/articles/1368211.pdf
Data publikacji:
2016
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Napędów i Maszyn Elektrycznych Komel
Tematy:
silnik indukcyjny
diagnostyka
analiza częstotliwościowa
analiza składowych głównych
induction motor
diagnostics
spectral analysis
principal component analysis
Opis:
This paper presents a novel design of a portable diagnostic analyzer, which is designed to fault detection of stator windings and the broken rotor bars in the induction motors of different power ratings. The measuring circuit of the system consists of two multi-range current clamps to measure the motor line current in two phases. Measurement signals are fed to the microprocessor-based recorder that transmits data samples to a portable computer using wireless communication technology - Bluetooth. In the role of the computer can be used any Android device (e.g. tablet), or ordinary notebook with Windows OS. Diagnostic software installed on a laptop computer analyzes the recorded signals of stator current, in terms of finding the diagnostic features characteristic of the stator and rotor faults. For this purpose, the current Park's vector modulus analysis and principal component analysis (PCA) were implemented.
W artykule przedstawiono nowatorską konstrukcję przenośnego analizatora diagnostycznego, który jest przeznaczony do wykrywania uszkodzeń uzwojeń stojana i wirnika w silnikach indukcyjnych o różnych mocach. Część pomiarową systemu stanowią dwa wielozakresowe przetworniki cęgowe, które mierzą prąd silnika w dwóch fazach. Sygnały pomiarowe doprowadzone są do mikroprocesorowego rejestratora, który przesyła próbki pomiarowe do komputera przenośnego, wykorzystując bezprzewodową technologię komunikacyjną - Bluetooth. W roli komputera można zastosować dowolne urządzenie z systemem Android (np. tablet), albo zwykły komputer przenośny (laptop) z systemem Windows. Oprogramowanie diagnostyczne zainstalowane na komputerze przenośnym analizuje zarejestrowane sygnały prądu stojana, pod kątem znalezienia diagnostycznych cech, charakterystycznych dla uszkodzeń stojana i wirnika. W tym celu zaimplementowano metody analizy częstotliwościowej wektora przestrzennego prądu stojana oraz metody analizy składowych głównych (PCA).
Źródło:
Maszyny Elektryczne: zeszyty problemowe; 2013, 3, 100/1; 177-182
0239-3646
2084-5618
Pojawia się w:
Maszyny Elektryczne: zeszyty problemowe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A comparison of algorithms for separation of synchronous subspaces
Autorzy:
Almeida, M.
Bioucas-Dias, J.
Vigário, R.
Oja, E.
Powiązania:
https://bibliotekanauki.pl/articles/201566.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
phase locking
synchrony
source separation
subspaces
Independent Component Analysis (ICA)
Independent Subspace Analysis (ISA)
magnetoencephalogram (MEG)
Opis:
Independent Subspace Analysis (ISA) consists in separating sets (subspaces) of dependent sources, with different sets being independent of each other. While a few algorithms have been proposed to solve this problem, they are all completely general in the sense that they do not make any assumptions on the intra-subspace dependency. In this paper, we address the ISA problem in the specific context of Separation of Synchronous Sources (SSS), i.e., we aim to solve the ISA problem when the intra-subspace dependency is known to be perfect phase synchrony between all sources in that subspace. We compare multiple algorithmic solutions for this problem, by analyzing their performance on an MEG-like dataset.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2012, 60, 3; 455-460
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nontrivial variations of morpho-anatomical leaf traits in natural south-eastern populations of vaccinium species from Central Balkans
Autorzy:
Bjedov, I.
Obratov-Petkovic, D.
Rakonjac, V.
Skocajic, D.
Bojovic, S.
Markovic, M.
Dajic-Stevanovic, Z.
Powiązania:
https://bibliotekanauki.pl/articles/2142112.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
Analysis of Variance
climate factors
Cluster Analysis
elevational gradient
Principal Component Analysis
Serbia
intraspecific and interspecific variability
Opis:
Morpho-anatomical characteristics of Vaccinium myrtillus, V. uliginosum and V. vitis-idaea leaves from several sites of the Central Balkans were examined. The aim of this study was to investigate for the first time morpho-anatomical leaf traits of these species in the studied populations and to identify traits that follow a specific trend along the gradients of climate factors. Leaf traits that discriminate Vaccinium species were as follows: depth of the adaxial cuticule (AdC), thickness of the palisade tissue (PT), thickness of the spongy tissue (ST), height of the abaxial epidermal cells (AbE), height of the abaxial cuticule (AbC) and leaf thickness (LT). Populations of V. myrtillus were characterized by the smallest, and populations of V. vitis-idaea by the highest values for AdC, PT, ST, AbE and LT. Additionally, AbC was significantly larger for V. uliginosum in comparison to two other species. On the basis of morpho-anatomical traits, intraspecific variability of the studied species was explored by Principal Component Analysis (PCA), Cluster Analysis (CA) and Analysis of Variance (ANOVA). CA based on 10 morpho-anatomical traits showed that populations of V. myrtillus and V. uliginosum that grew at lower altitudes (characterized by higher mean annual temperature) are more similar to each other. Especially V. myrtillus was responsive to the elevational gradient and exhibited the highest plasticity in morpho-anatomical leaf traits. Populations of V. vitis-idaea had a different pattern of differentiation along the elevational gradient. CA showed that the populations at the lowest and at the highest altitudes were more similar according to the morpho-anatomical leaf traits, meaning that evergreen leaves were more resistant to environmental conditions.
Źródło:
Acta Biologica Cracoviensia. Series Botanica; 2021, 63, 2; 7-16
0001-5296
Pojawia się w:
Acta Biologica Cracoviensia. Series Botanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Removing physiological artifacts from the EEG data by algorithms based on differential entropy
Eliminacja artefaktów fizjologicznych z zapisu EEG przez algorytmy stosujące entropię różniczkową
Autorzy:
Górecka, J.
Powiązania:
https://bibliotekanauki.pl/articles/152185.pdf
Data publikacji:
2012
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
entropia różniczkowa
analiza składowych niezależnych
zapis EEG
differential entropy
independent component analysis
EEG data
Opis:
A new form of the nonlinearity implemented in the ICA approach is presented in the paper. The proposed independent component analysis based on differential entropy can be used for elimination of physiological artifacts from electroencephalographic signals. For verification of the quality of separation of the EEG data, the PI index is proposed. The second measure of accuracy is the normalized kurtosis which can be used in analysis of the simulated EEG data. As it has been proved, the new sigmoid function used in the ICA approach can effectively separate the EEG data.
W artykule przedstawiono nową propozycję nieliniowości - sigmoidalną funkcję algebraiczną, która została zaimplementowana w algorytmie stosującym metodę analizy składowych niezależnych (ang. Independent Component Analysis). Proponowana nowa postać algorytmu wykorzystująca właściwości entropii różniczkowej, może zostać użyta także do separacji a następnie eliminacji wybranych artefaktów fizjologicznych pochodzenia ocznego i mięśniowego zarejestrowanych w zapisach EEG. W celu weryfikacji dokładności separacji sygnałów EEG zaproponowano współczynnik jakości separacji PI (ang. Performance Index). Jako drugą miarę dokładności procesu separacji wybrano wartość znormalizowanej kurtozy, która może być stosowana jedynie w przypadku separacji elektroencefalogramów zarejestrowanych z symulatora EEG. W artykule udowodniono, że użycie nowej funkcji sigmoidalnej w rozszerzonej postaci algorytmu infomax prowadzi do efektywnej separacji sygnałów EEG umożliwiając eliminację wybranych składowych niepożądanych.
Źródło:
Pomiary Automatyka Kontrola; 2012, R. 58, nr 11, 11; 975-977
0032-4140
Pojawia się w:
Pomiary Automatyka Kontrola
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation and selection process of suppliers through analytical framework: an emprical evidence of evaluation tool
Autorzy:
Imeri, S.
Shahzad, K.
Takala, J.
Liu, Y
Sillanpää, I.
Ali, T.
Powiązania:
https://bibliotekanauki.pl/articles/407383.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
supplier evaluation
supplier performance management
supplier selection model
principal component analysis
supply chain management
Opis:
The supplier selection process is very important to companies as selecting the right suppliers that fit companies strategy needs brings drastic savings. Therefore, this paper seeks to address the key area of supplies evaluation from the supplier review perspective. The purpose was to identify the most important criteria for suppliers’ evaluation and develop evaluation tool based on surveyed criteria. The research was conducted through structured questionnaire and the sample focused on small to medium sized companies (SMEs) in Greece. In total eighty companies participated in the survey answering the full questionnaire which consisted of questions whether these companies utilize some suppliers’ evaluation criteria and what criteria if any is applied. The main statistical instrument used in the study is Principal Component Analysis (PCA). Thus, the research has shown that the main criteria are: the attitude of the vendor towards the customer, supplier delivery time, product quality and price. Conclusions are made on the suitability and usefulness of suppliers’ evaluation criteria and in way they are applied in enterprises.
Źródło:
Management and Production Engineering Review; 2015, 6, 3; 10-20
2080-8208
2082-1344
Pojawia się w:
Management and Production Engineering Review
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Convergence Analysis for Principal Component Flows
Autorzy:
Yoshizawa, S.
Helmke, U.
Starkov, K.
Powiązania:
https://bibliotekanauki.pl/articles/908317.pdf
Data publikacji:
2001
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
badanie zbieżności
sieć neuronowa
principal component analysis
neural networks
gradient flows
phase portrait
Hessians
Opis:
A common framework for analyzing the global convergence of several flows for principal component analysis is developed. It is shown that flows proposed by Brockett, Oja, Xu and others are all gradient flows and the global convergence of these flows to single equilibrium points is established. The signature of the Hessian at each critical point is determined.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2001, 11, 1; 223-236
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mierzenie ryzyka stóp procentowych: przypadek rynku międzybankowego w Polsce
Interest rate risk measurement: the Polish interbank market case
Autorzy:
Olsza, Paweł
Powiązania:
https://bibliotekanauki.pl/articles/422739.pdf
Data publikacji:
2012
Wydawca:
Główny Urząd Statystyczny
Tematy:
zabezpieczenie
analiza głównych składowych
ryzyko stóp procentowych
hedging
principal component analysis
interest rate risk
Opis:
W artykule przedstawiony został przykład zastosowania różnych podejść do pomiaru ryzyka stóp procentowych. Analizy empiryczne zaprezentowane w artykule przeprowadzono z wykorzystaniem danych z polskiego rynku międzybankowego za okres od 5 września 2000 roku do 19 listopada 2010 roku. Zaprezentowano narzędzia pomiaru ryzyka stóp procentowych, bazujące na wartościach wektorów własnych odpowiadających poszczególnym głównym składowym. Miary te, poprzez nadanie stosownej interpretacji ekonomicznej poszczególnych głównych składowych, mogą mieć także zastosowanie w analizie wrażliwości portfela instrumentów dłużnych na określone ruchy krzywej terminowej stóp procentowych. W artykule omówiono także kwestię odpowiedniego doboru oraz możliwego wpływu zakresu wykorzystywanych danych rynkowych na wartości oraz stabilność oszacowań wektorów własnych uzyskiwanych z użyciem analizy głównych składowych. W celu sprawdzenia efektywności pomiaru ryzyka stopy procentowej z wykorzystaniem analizy głównych składowych dokonano pomiaru skuteczności trzech różnych strategii zabezpieczających, pierwszej utworzonej na podstawie wskazań miar wrażliwości analizowanego portfela na zmiany poszczególnych głównych składowych, drugiej bazującej na miarach duracji efektywnej, wypukłości efektywnej oraz BPV oraz przy założeniu braku zabezpieczenia. Uzyskane wyniki nie wykazały znaczących różnic w stopniu zabezpieczenia portfela w przypadku strategii zabezpieczających wykorzystujących główne składowe oraz miary duracji efektywnej, wypukłości efektywnej oraz BPV.
The article presents an example of the application of different approaches to the measurement of interest rate risk. Empirical analysis described in the article was carried out using data from the Polish interbank market for the period from September 5th, 2000 to November 19th, 2010. Interest rate risk measurement techniques using principal component analysis (PCA) are presented in the article. These techniques, by giving appropriate economic interpretation of each principal component, can also be used in the sensitivity analysis of the portfolio of debt securities to specific interest rate curve movements. The article also discusses the issue of the appropriate selection of scope and range of market data used in the analysis and its possible impact on values and stability of eigenvectors obtained using PCA. Three different hedging strategies were tested in order to check the effectiveness of interest rate risk measurement using PCA, the first based on PCA, the other based on the measures of effective duration, effective convexity, and BPV, the last considered strategy assumed no hedging at all. The results showed no significant differences in the degree of portfolio value protection in case of hedging strategy using PCA and the one based on the measures of effective duration, effective convexity, and BPV.
Źródło:
Przegląd Statystyczny; 2012, 59, 4; 434-454
0033-2372
Pojawia się w:
Przegląd Statystyczny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wielowymiarowa analiza czynników sukcesu projektów IT
Multidimensional Analysis of Factors of IT Project Success
Autorzy:
Gładysz, Barbara
Frączkowski, Kazimierz
Powiązania:
https://bibliotekanauki.pl/articles/589729.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Ekonomiczny w Katowicach
Tematy:
Analiza składowych głównych
Czynniki sukcesu
Projekt IT
Principal component analysis
Project IT
Success factors
Opis:
Dzięki postępowi technologicznemu, który nastąpił w ostatnich latach, znacznie wzrosła liczba projektów informatycznych. Projekty te często okazywały się skomplikowanymi przedsięwzięciami obarczonymi wysokim ryzykiem. Właściwe zarządzanie projektem może wpłynąć na harmonogram, budżet i jakość projektu, a tym samym przyczynić się do sukcesu projektu. W artykule dokonano wielowymiarowej analizy czynników sukcesu projektu. Badania zostały przeprowadzone na podstawie danych ankietowych.
Due to technological advances in recent years, the number of IT projects has significantly increased. Such projects are often complicated and associated with high risk. Appropriate project management has a positive influence on the budget, quality and achieving deadlines, and in this way can lead to the success of a project. This paper presents and multi-criterion analysis of factors involved in the success/failure of a project. This research was carried out on the basis of data from a questionnaire.
Źródło:
Studia Ekonomiczne; 2015, 248; 80-89
2083-8611
Pojawia się w:
Studia Ekonomiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Główne składowe rozwoju inteligentnego Polski
Principal components of the smart development of Poland
Autorzy:
Rozmus, Dorota
Trzęsiok, Joanna
Powiązania:
https://bibliotekanauki.pl/articles/542528.pdf
Data publikacji:
2018-05-28
Wydawca:
Główny Urząd Statystyczny
Tematy:
polityka spójności
rozwój inteligentny
metoda głównych składowych
cohesion policy
smart development
principal component analysis
Opis:
W systemie STRATEG, utworzonym przez GUS na potrzeby monitorowania polityki spójności, zgromadzono ponad 300 wskaźników do pomiaru rozwoju inteligentnego. Z uwagi na dużą liczbę zmiennych zasadne wydaje się zbadanie możliwości konstrukcji wskaźników syntetycznych jak najlepiej reprezentujących zmienne pierwotne. Celem badania, które przeprowadzono na podstawie danych z baz STRATEG i BDL za 2015 r., jest wskazanie — dzięki zastosowaniu analizy czynnikowej — głównych składowych rozwoju inteligentnego w Polsce, informujących o najważniejszych obszarach charakteryzowanych przez wskaźniki rozwoju inteligentnego. W efekcie uzyskano siedem głównych składowych, łącznie wyjaśniających ponad 94% wariancji pierwotnego zbioru wskaźników, dla których zaproponowano merytoryczną interpretację.
The STRATEG system created by Statistics Poland for monitoring cohesion policy, contains more than 300 indicators for measuring smart development. Due to a large number of variables, it seems appropriate to examine the possibility of constructing synthetic indicators that best represent the primary variables. The aim of this study, which was conducted on the basis of data for 2015 from the STRATEG and BDL databases, is to identify, owing to the use of factor analysis, the main components of smart development in Poland, informing about the most important areas characterised by the indicators of smart development. As a result 7 main components were obtained, which together account for more than 94% of variance from the original set of indicators and for which a substantive interpretation was proposed.
Źródło:
Wiadomości Statystyczne. The Polish Statistician; 2018, 63, 5; 25-36
0043-518X
Pojawia się w:
Wiadomości Statystyczne. The Polish Statistician
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multifactorial components analysis of the renewable energy sector in the OECD countries and managerial implications
Analiza komponentów wielofunkcyjnych sektora energii odnawialnej w krajach OECD i implikacje kierownicze
Autorzy:
Androniceanu, Ane-Mari
Georgescu, Irina
Dobrin, Cosmin
Dragulanescu, Irina Virginia
Powiązania:
https://bibliotekanauki.pl/articles/2021559.pdf
Data publikacji:
2020
Wydawca:
Politechnika Częstochowska
Tematy:
renewable energy
principal component analysis
government policy
energia odnawialna
analiza głównych komponentów
polityka rządu
Opis:
New technologies and new market realities determine the global energy industry to redesign their business models in all significant areas. We based our research on the components of renewable energy within the OECD countries and used thirteen indicators in order to find out both the relations and the impact of main sectorial indicators and the global indicators of the OECD countries to their economic and social development. The main goal of our research is to discover the main correlations between the renewable energies and the economic development of the OECD countries. We used databases of the OECD, Our World in Data, International Energy Agency (IEA) and International Renewable Energy Agency (IRENA), available for years 2017 and 2018. We apply Principal Component Analysis (PCA) and retain three principal components explaining 76.098% of the total variance. The main findings of the PCA application are; (1) factor 1 is dominated by the main renewable energy sources: traditional biofuels, hydropower, solar, wind and other renewables, as well as energy products, energy exports, energy capacity and energy generation; (2) factor 2 is dominated positively by energy imports and negatively by primary energy supply and GDP per capita; (3) factor 3 measures electricity generation. The results are addressed to the OECD member states, but also to other categories of states. Our results clearly show that if the OECD states are developing coherent renewable energy policies as part of an integrated smart energy system. The results show a direct link between investments in renewable energy and macroeconomic indicators of the considered states and main implications to the management.
Nowe technologie i nowe realia rynkowe determinują globalny przemysł energetyczny do przeprojektowania modeli biznesowych we wszystkich istotnych obszarach. Nasze badania oparliśmy na składnikach energii odnawialnej w krajach OECD i wykorzystaliśmy trzynaście wskaźników, aby poznać zarówno relacje, jak i wpływ głównych wskaźników sektorowych oraz wskaźników globalnych krajów OECD na ich rozwój gospodarczy i społeczny. Głównym celem naszych badań jest odkrycie głównych korelacji między energią odnawialną a rozwojem gospodarczym krajów OECD. Korzystaliśmy z baz danych OECD, Our World in Data, Międzynarodowej Agencji Energii (IEA) i Międzynarodowej Agencji Energii Odnawialnej (IRENA), dostępnych za lata 2017 i 2018. Stosujemy analizę głównych komponentów (PCA) i zatrzymujemy trzy główne komponenty wyjaśniające 76,098% całkowitej wariancji. Główne ustalenia wniosku o PCA są następujące; (1) czynnik 1 jest zdominowany przez główne odnawialne źródła energii: tradycyjne biopaliwa, energię wodną, słoneczną, wiatrową i inne odnawialne źródła energii, a także produkty energetyczne, eksport energii, moc i wytwarzanie energii; (2) czynnik 2 jest zdominowany pozytywnie przez import energii, a negatywnie przez podaż energii pierwotnej i PKB na mieszkańca; (3) współczynnik 3 mierzy wytwarzanie energii elektrycznej. Wyniki skierowane są do krajów członkowskich OECD, ale także do innych kategorii państw. Nasze wyniki jasno pokazują, że państwa OECD opracowują spójną politykę w zakresie energii odnawialnej w ramach zintegrowanego inteligentnego systemu energetycznego. Wyniki wskazują na bezpośredni związek między inwestycjami w energię odnawialną a wskaźnikami makroekonomicznymi rozważanych krajów i głównymi implikacjami dla zarządzania.
Źródło:
Polish Journal of Management Studies; 2020, 22, 2; 36-49
2081-7452
Pojawia się w:
Polish Journal of Management Studies
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The impact of water quality on the availability of phytoplankton and growth of Litopenaeus vannamei
Autorzy:
Musa, Muhammad
Thoyibah, Auliarifka A.
Puspitaningtyas, Dyah A.
Arsad, Sulastri
Mahmudi, Mohammad
Lusiana, Evellin D.
Maftuch, Maftuch
Huda, Agus S.
Powiązania:
https://bibliotekanauki.pl/articles/2203547.pdf
Data publikacji:
2023
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
algae
aquaculture
canonical correspondence analysis
CCA
dynamics of water quality
principal component analysis
PCA
vannamei shrimp
Opis:
This research analysed the availability of phytoplankton and the growth rate of Vannamei shrimp in relation to water quality changes. The research was carried out in February-March 2021 for a half cycle of shrimp cultivation in two ponds of the Brackish Water Fish Culture Probolinggo Laboratory in Probolinggo, East Java, Indonesia. The research used a descriptive method and included a survey. Sampling was made every two weeks for two months. Nine parameters were measured and ten shrimps were taken for a specific growth rate (SGR) measurement once per sampling. Data were analysed using the principal component analysis (PCA) and canonical correspondence analysis (CCA). Secondary data of water quality were added for the PCA. The results show that the phytoplankton found in the first pond consisted of Chlorophyta, Chrysophyta, and Cyanophyta, whereas the phytoplankton in the other pond included Chlorophyta, Chrysophyta, Cyanophyta, and Dinophyta. The abundance of phytoplankton ranged from 12-80∙103 cell∙cm-3, which indicated eutrophic waters. The PCA demonstrated that pH, nitrate, and total organic matter (TOM) significantly influenced phytoplankton abundance in the pond. In addition, water quality parameters, such as temperature, transparency, salinity, nitrite and phosphate levels, were tolerable in both ponds for the growth of shrimps. However, the level of pH was lower than the aquaculture quality standard, whereas those of nitrate, ammonia, and TOM were higher. The growth rate of Vannamei shrimp increased by 0.76–7.34%∙day-1.
Źródło:
Journal of Water and Land Development; 2023, 56; 127--135
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
PCA Based Components Selection Criteria for Computationally Efficient Physical Layer Key Generation (PLKG) System
Autorzy:
Sarsodia, Tapesh
Bhatt, Uma Rathore
Upadhyay, Raksha
Bhat, Vijay
Powiązania:
https://bibliotekanauki.pl/articles/27311925.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
wireless networks
received signal strength
principal component analysis
physical layer key generation
Mean
Histfit
Opis:
Data security is one of the prime concerns in wireless networks. PLKG has been emerging as an attractive alternative to traditional cryptographic techniques. PLKG is more computationally efficient than cryptography. Moreover, PLKG using Principal component analysis (PCA) as pre-processing may further save computations. This paper proposes three mechanisms to select components of PCA which are based on Information content, Mean and Histfit. Bit Disagreement Rate (BDR) is compared for each mechanism. Histfit based method is found to be best. Since only two components are supposed to be processed for key generation, it is computationally efficient/ power efficient too.
Źródło:
International Journal of Electronics and Telecommunications; 2023, 69, 2; 361--369
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Machining Investigations of Squeeze Cast TiB2/Al 7075 Composites through EDM: Regression Modelling and Weighted Principal Component Analysis
Autorzy:
Pradhan, Rahul Chandra
Das, Diptikanta
Sahoo, Barada Prasanna
Rout, Chiranjeeb
Panda, Akash
Barla, Evangelin
Powiązania:
https://bibliotekanauki.pl/articles/27324484.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
Al 7075
TiB2
metal matrix composite
electrical discharge machining
weighted principal component analysis
Opis:
2 wt.% TiB2 (mean particle size: 400 nm) reinforced Al 7075 metal matrix composites (MMCs) fabricated through mechanical stirring and ultrasonic agitation integrated squeeze casting process were subjected to electrical discharge machining (EDM) after determining the physical and mechanical properties. EDM was conducted with Cu electrode tools to investigate influence of machining factors, i.e. peak current (IP), pulse on time (TON) and gap voltage (VG) on the tool wear rate (TWR), material removal rate (MRR) and average surface roughness (ASR) of the machined surfaces. All the three responses increased on increasing IP and TON, but reduced on increasing VG. The machined surfaces were studied through scanning electron microscope (SEM). Significance of the EDM parameters on the individual responses were studied using analysis of variance (ANOVA) and regression models for the responses were developed using response surface method (RSM). The responses under consideration were optimized simultaneously using Taguchi embedded weighted principal component analysis (WPCA), which resulted the parametric combination of 4A (current), 100 μs (pulse duration) and 75V (voltage) was the optimal setting for the multi-criteria decision problem. Finally, the result of optimization was validated by conducting some confirmatory experiments.
Źródło:
Archives of Metallurgy and Materials; 2023, 68, 2; 551--562
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Principal component analysis of chlorophyll content in tobacco, bean and petunia plants exposed to different tropospheric ozone concentrations
Analiza składowych głównych zawartości chlorofilu w roślinach tytoniu, fasoli i petunii eksponowanych na stanowiskach o różnych stężeniach ozonu troposferycznego
Autorzy:
Borowiak, K.
Zbierska, J.
Budka, A.
Kayzer, D.
Powiązania:
https://bibliotekanauki.pl/articles/396114.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
tropospheric ozone
sensitive
resistance
chlorophyll
principal component analysis (PCA)
ozon troposferyczny
wrażliwość
odporność
chlorofil
Opis:
Three plant species were assessed in this study - ozone-sensitive and -resistant tobacco, ozone-sensitive petunia and bean. Plants were exposed to ambient air conditions for several weeks in two sites differing in tropospheric ozone concentrations in the growing season of 2009. Every week chlorophyll contents were analysed. Cumulative ozone effects on the chlorophyll content in relation to other meteorological parameters were evaluated using principal component analysis, while the relation between certain days of measurements of the plants were analysed using multivariate analysis of variance. Results revealed variability between plant species response. However, some similarities were noted. Positive relations of all chlorophyll forms to cumulative ozone concentration (AOT 40) were found for all the plant species that were examined. The chlorophyll b/a ratio revealed an opposite position to ozone concentration only in the ozone-resistant tobacco cultivar. In all the plant species the highest average chlorophyll content was noted after the 7th day of the experiment. Afterwards, the plants usually revealed various responses. Ozone-sensitive tobacco revealed decrease of chlorophyll content, and after few weeks of decline again an increase was observed. Probably, due to the accommodation for the stress factor. While during first three weeks relatively high levels of chlorophyll contents were noted in ozone-resistant tobacco. Petunia revealed a slow decrease of chlorophyll content and the lowest values at the end of the experiment. A comparison between the plant species revealed the highest level of chlorophyll contents in ozone-resistant tobacco.
W zaprezentowanych badaniach wykorzystano trzy gatunki roślin - tytoń szlachetny (odmiana wrażliwa oraz odporna na ozon), odmiany wrażliwe petunii oraz fasoli. Rośliny eksponowano na dwóch stanowiskach różniących się stężeniem ozonu troposferycznego w sezonie wegetacyjnym 2009 roku. Co tydzień wykonywano pomiary zawartości chlorofilu wybranych roślin. Powiązanie kumulatywnych stężeń ozonu względem zawartości chlorofilu oraz wybranych parametrów meteorologicznych wykonano za pomocą analizy składowych głównych, natomiast do porównania reakcji roślin w poszczególnych dniach ekspozycji wykorzystano wielowymiarową analizę wariancji. Badania wykazały zróżnicowanie pomiędzy gatunkami w reakcji na obecność ozonu troposferycznego. Zauważyć jednak można pewne tendencje. Stwierdzono pozytywną zależność pomiędzy zawartością wszystkich form chlorofilu dla wszystkich badanych gatunków i kumulatywnym stężeniem ozonu (AOT 40). Wskaźnik chlorofilu b/a wykazał odwrotną tendencję względem AOT 40 jedynie dla odmiany odpornej na ozon tytoniu. Wszystkie gatunki wykazały najwyższy poziom chlorofilu w 7 dniu ekspozycji, a w następnych dniach odpowiedź roślin była zróżnicowana. Odmiana wrażliwa tytoniu wykazała zmniejszenie zawartości chlorofilu, a po kilku tygodniach ponownie wzrost, co może sugerować adaptację do warunków stresowych. Odmiana odporna tytoniu ekspozycji. Petunia wykazała stopniowy spadek zawartości chlorofilu w ciągu trwania eksperymentu. Porównanie odpowiedzi wybranych gatunków wykazało najwyższe poziomy chlorofilu u odmiany odpornej tytoniu.
Źródło:
Civil and Environmental Engineering Reports; 2014, 12; 5-16
2080-5187
2450-8594
Pojawia się w:
Civil and Environmental Engineering Reports
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparison of Selected Multiple Imputation Methods for Continuous Variables – Preliminary Simulation Study Results
Porównanie wybranych metod imputacji wielokrotnej dla zmiennych ilościowych – wstępne wyniki badań symulacyjnych
Autorzy:
Misztal, Małgorzata Aleksandra
Powiązania:
https://bibliotekanauki.pl/articles/656755.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
dane niekompletne
imputacja wielokrotna
analiza głównych składowych
missForest
incomplete data
multiple imputation
principal component analysis
Opis:
Problem występowania danych niekompletnych i ich wpływu na wyniki analiz statystycznych nie jest związany z żadną konkretną dziedziną nauki – pojawia się w ekonomii, socjologii, edukacji, naukach behawioralnych czy medycynie. W przypadku większości klasycznych metod statystycznych wymagana jest kompletna informacja o zmiennych charakteryzujących badane obiekty, a typowym podejściem do brakujących danych jest po prostu ich usunięcie. Prowadzi to jednak do niewiarygodnych i obciążonych wyników analiz i nie jest zalecane w literaturze przedmiotu. Rekomendowaną metodą postępowania z brakującymi danymi jest imputacja wielokrotna. W artykule rozważono kilka wybranych jej metod. Szczególną uwagę zwrócono na wykorzystanie analizy głównych składowych (PCA) jako metody imputacji. Celem pracy była ocena jakości imputacji opartej na PCA na tle dwóch innych technik uzupełniania braków danych: imputacji wielokrotnej za pomocą równań łańcuchowych (MICE) i metody missForest. Porównania metod imputacji dokonano, wykorzystując podejście symulacyjne i generując braki danych w 10 kompletnych zbiorach danych z repozytorium baz danych Uniwersytetu Kalifornijskiego w Irvine, z uwzględnieniem różnych mechanizmów generowania braków danych oraz różnych proporcji (10–50%) brakujących wartości. Do imputacji brakujących wartości zastosowano metodę równań łańcuchowych, metodę missForest oraz metodę opartą na głównych składowych (MIPCA). Znormalizowany pierwiastek kwadratowy błędu średniokwadratowego (NRMSE) wykorzystano jako miarę dokładności imputacji. Na podstawie przeprowadzonych analiz metoda missForest może być rekomendowana jako ta metoda wielokrotnej imputacji, która zapewnia najwyższą dokładność imputacji braków danych. Imputacja oparta na analizie głównych składowych (PCA) nie prowadzi do zadowalających wyników.
The problem of incomplete data and its implications for drawing valid conclusions from statistical analyses is not related to any particular scientific domain, it arises in economics, sociology, education, behavioural sciences or medicine. Almost all standard statistical methods presume that every object has information on every variable to be included in the analysis and the typical approach to missing data is simply to delete them. However, this leads to ineffective and biased analysis results and is not recommended in the literature. The state of the art technique for handling missing data is multiple imputation. In the paper, some selected multiple imputation methods were taken into account. Special attention was paid to using principal components analysis (PCA) as an imputation method. The goal of the study was to assess the quality of PCA‑based imputations as compared to two other multiple imputation techniques: multivariate imputation by chained equations (MICE) and missForest. The comparison was made by artificially simulating different proportions (10–50%) and mechanisms of missing data using 10 complete data sets from the UCI repository of machine learning databases. Then, missing values were imputed with the use of MICE, missForest and the PCA‑based method (MIPCA). The normalised root mean square error (NRMSE) was calculated as a measure of imputation accuracy. On the basis of the conducted analyses, missForest can be recommended as a multiple imputation method providing the lowest rates of imputation errors for all types of missingness. PCA‑based imputation does not perform well in terms of accuracy.
Źródło:
Acta Universitatis Lodziensis. Folia Oeconomica; 2018, 6, 339; 73-98
0208-6018
2353-7663
Pojawia się w:
Acta Universitatis Lodziensis. Folia Oeconomica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment of soil quality in organic and non-organic paddy fields with technical irrigation system in Susukan
Autorzy:
Haryuni, H.
Wirawati, H.
Minardi, S.
Supriyadi, S.
Powiązania:
https://bibliotekanauki.pl/articles/971160.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Tematy:
soil quality
paddy fields
principal component analysis
minimum data set (mds)
soil quality index (sqi)
Opis:
Soil quality is a measure of the condition of soil. The goal of sustainable agriculture is to maintain a non-negative trend in productivity while maintaining soil quality. Susukan is an area in Semarang, Central Java, Indonesia, which has developed organic farming to increase rice productiv- ity and quality. The main objective was to determine the sustainability of organic rice cropping sys- tems. The organic farming system at the research location has been conducted for 8 years. Appropri- ate agricultural management can maintain the quality of soil, environment and improve the health of plants, animals and humans. This research aims to know the soil quality and determine the minimum data set (MDS) in organic and non-organic paddy field with a technical irrigation system. Paddy soil samples were analyzed in the laboratory. The parameters are porosity, permeability, hydrogen potential (pH), cation exchange capacity (CEC), soil organic matter (SOC), total-N (nitrogen), car- bon/nitrogen (C/N) ratio, available-P (phosphorus), available-K (potassium), base saturation (BS), electric conductivity (EC), soil respiration (qCO2), redox potential (Eh) with 3 repetitions. The value of soil quality index (SQI) in the organic paddy field is 3.216 with bad soil quality criteria, while the non-organic paddy field is 0.147 with very bad criteria. The soil quality values are based on the key factors or MDS that is potential redox (EH), soil respiration (qCO2), potential hydrogen (pH), poros- ity, soil organic matter (SOC), total-N (nitrogen), C/N ratio, available-P (phosphorus).
Źródło:
Polish Journal of Soil Science; 2020, 53, 1
0079-2985
Pojawia się w:
Polish Journal of Soil Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Soil quality assessment of the rainfed lowland ricefields under organic and conventional farming systems in Kaliwungu (Central Java)
Autorzy:
Supriyadi, Supriyadi
Rachmawati, Septiana
Herawati, Aktavia
Purwanto, Purwanto
Powiązania:
https://bibliotekanauki.pl/articles/762795.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Tematy:
soil quality index (SQI), rainfed lowland rice, principal component analysis (PCA), minimum data set (MDS)
Opis:
Rainfed lowland rice is grown in land where the irrigation systems depend on rainwater. The use of chemical fertilizers in large quantities in order to improve production of rice will result in soil quality degradation. In order to improve the condition of the soil, a system of organic farming was provided. The aim of this study was to quantify soil quality in rainfed lowland ricefilds using soil quality indexes (SQI) and to compare SQIs of farming system under organic and conventional fertilization. The sample consists of seven sample points on soil fertilized organically and three sample points on soil which is managed in a conventional way, each taken from 5 subpoints at a depth of 0–30 cm and analyzed for 12 soil variables. The best representative soil quality variables forming a minimum data set (MDS) were selected using principal component analysis (PCA), and soil quality scores were obtained using both linear and non-linear scoring functions. The study results indicate that in case of organic farming system, the soil quality was better (SQI = 2.079) when compared to its quality in the conventional farming system (SQI = 1.397). The selected indicators used as the MDS are soil porosity, cation exchange capacity (CEC), soil organic carbon, C/N ratio, soil permeability, available-P (Av-P), and electrical conductivity (EC)
Źródło:
Polish Journal of Soil Science; 2018, 51, 2
0079-2985
Pojawia się w:
Polish Journal of Soil Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
NEUROPSYCHOLOGY AND THE NEUROPHYSIOLOGY OF PERCEPTUAL MICROGENESIS
Autorzy:
Pąchalska, Maria
Góral-Pólrola, Jolanta
Mueller, Andreas
Kropotov, Juri D
Powiązania:
https://bibliotekanauki.pl/articles/2137785.pdf
Data publikacji:
2017-12-18
Wydawca:
Fundacja Edukacji Medycznej, Promocji Zdrowia, Sztuki i Kultury Ars Medica
Tematy:
microgenetic theory
event related potentials
stages of information flow
ventral visual stream
independent component analysis
Opis:
Perception is one of the psychological operations that can be analyzed from the point of view of microgenetic theory. Our study tests the basic premise of microgenesis theory – the existence of recurrent stages of visual information processing. The event related potentials in two variants of a cued GO/NOGO task (contrasting images of Animals and Plants in the first variant, and contrasting images of Angry and Happy faces in the second variant) were studied during the first 300 ms following stimulus presentation. The independent component analysis was applied to a large collection of ERPs. The functional independent components associated with visual category discrimination, comparison to working memory, action initiation and conflict detection were separated. Information processing in the ventral visual stream (the temporal independent components) occurs at two sequential stages with positive/negative fluctuations of the cortical potential as indexes of the stages. The first stage represents the comparison of the pure physical features of the visual input with the memory trace. The second stage represents the comparison of more sophisticated semantic/emotional features with the working memory. The two stages are the results of interplay between bottom-up and top-down projections in the visual ventral stream.
Źródło:
Acta Neuropsychologica; 2017, 15(4); 365-389
1730-7503
2084-4298
Pojawia się w:
Acta Neuropsychologica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Identification of changes of machine technical state on the basis of results of principle component analysis of a sequence of thermographic images
Identyfikacja zmian stanu obiektów technicznych na podstawie wyników analizy głównych składowych sekwencji zdjęć termograficznych
Autorzy:
Fidali, M.
Bzymek, A.
Powiązania:
https://bibliotekanauki.pl/articles/327752.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
Tematy:
diagnostyka
maszyna
termowizja
termografia
analiza głównych składowych
machine
diagnostics
thermovision
thermography
principal component analysis
PCA
Opis:
During continuous object observation with the use of a thermographic device, a sequence of thermographic images can be recorded in time function. On the basis of an acquired series of thermograms, determination of diagnostic signals and identification of changes of a machine technical state is possible. An approach presented in the paper concerns application of a Principal Component Analysis (PCA) method. In order to verify the method, an active diagnostic experiment, during which sequences of thermographic images were recorded and analyzed according to their components, was carried out. The obtained results showed that diagnostic signals provided by PCA could be used for identification of changes of a technical state as well as classification of the state with considerably high efficiency.
Podczas ciągłej obserwacji termowizyjnej obiektu technicznego rejestrowana jest sekwencja obrazów w czasie. Na podstawie zarejestrowanej sekwencji obrazów możliwe jest wyznaczenie sygnałów diagnostycznych pozwalających na identyfikację stanu technicznego obserwowanego obiektu. W artykule zaproponowano metodę diagnozowania maszyn na podstawie wyników analizy składowych głównych (PCA) sekwencji obrazów termowizyjnych. W celu weryfikacji metody przeprowadzono czynny eksperyment diagnostyczny, podczas którego rejestrowano sekwencje obrazów, które poddano analizie składowych. Uzyskane wyniki wykazały, że metoda składowych głównych pozwala na identyfikację zmian stanu technicznego oraz efektywną klasyfikację stanu technicznego maszyny.
Źródło:
Diagnostyka; 2009, 3(51); 45-48
1641-6414
2449-5220
Pojawia się w:
Diagnostyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multivariate Statistical Analysis of Groundwater Quality of Hassi Rmel, Algeria
Autorzy:
Mehdi, Metaiche
Hakim, Djafer Khodja
Amina, Aichour
Nourredine, Gaci
Powiązania:
https://bibliotekanauki.pl/articles/24201762.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
groundwater
water quality
principal component analysis
PCA
ascending hierarchical classification
HAC
diagram analysis
Hassi R'mel region
Opis:
The quality of Groundwater is characterized by physico-chemical parameters. They determine the way in which this water is used (water supply, irrigation, industry, etc.). This present study gives the highlighting of the hydrogeological and physico-chemical characteristics of aquifer waters in question resulting from the various wells, which aims to; gather, exploit and analyze the data, in order to determine their conformity with potability standards and their suitability for irrigation. Using multivariate statistical techniques including Principal Component Analysis (PCA), Hierarchical Cluster Analysis (ACH) and Diagram Analysis. They are applied to a dataset composed of 17 boreholes with 12 chemical variables over the entire study area, they were sampled in 2020. These boreholes are the principal water resources suppling Hassi R'mel w. Laghouat region in terms of drinking water and irrigation. Obtained results showed that the majority of groundwater in the Hassi R’mel region is hard; where approximately 20% of boreholes are characterized by fairly soft water, and approximately 5% are characterized by very hard water.
Źródło:
Journal of Ecological Engineering; 2023, 24, 5; 22--31
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spatio-temporal variability of the size-fractionated primary production and chlorophyll in the Levantine Basin (Northeastern Mediterranean)
Autorzy:
Yucel, N.
Powiązania:
https://bibliotekanauki.pl/articles/48586.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
spatio-temporal variability
primary production
chlorophyll a
phytoplankton
ecosystem
nutrient analysis
temperature
salinity
principal component analysis
Mediterranean Basin
Źródło:
Oceanologia; 2018, 60, 3
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
FUNCTIONAL EXPLORATORY DATA ANALYSIS OF UNEMPLOYMENT RATE FOR VARIOUS COUNTRIES
Autorzy:
Jaworski, Stanislaw
Powiązania:
https://bibliotekanauki.pl/articles/453521.pdf
Data publikacji:
2013
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Katedra Ekonometrii i Statystyki
Tematy:
B-splines basis system
smoothing with roughness penalty functional principal component analysis
cluster analysis
depth measures
unemployment rate
Opis:
Functional exploratory techniques are applied in the analysis of an unemployment rate. The rate is smoothed into differentiable function in order to facilitate the analysis. The main aim of the analysis is assigned to find out the unemployment curves which do not follow the same pattern as that of the other ones.
Źródło:
Metody Ilościowe w Badaniach Ekonomicznych; 2013, 14, 1; 180-189
2082-792X
Pojawia się w:
Metody Ilościowe w Badaniach Ekonomicznych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment of soil quality in organic and non-organic paddy fields with technical irrigation system in Susukan
Autorzy:
Haryuni, Haryuni
Wirawati, Hesti
Minardi, Slamet
Supriyadi, Supriyadi
Powiązania:
https://bibliotekanauki.pl/articles/2088202.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Tematy:
soil quality
paddy fields
principal component analysis
minimum data set (MDS)
soil quality index (SQI)
Opis:
Soil quality is a measure of the condition of soil. The goal of sustainable agriculture is to maintain a non-negative trend in productivity while maintaining soil quality. Susukan is an area in Semarang, Central Java, Indonesia, which has developed organic farming to increase rice productivity and quality. The main objective was to determine the sustainability of organic rice cropping systems. The organic farming system at the research location has been conducted for 8 years. Appropriate agricultural management can maintain the quality of soil, environment and improve the health of plants, animals and humans. This research aims to know the soil quality and determine the minimum data set (MDS) in organic and non-organic paddy field with a technical irrigation system. Paddy soil samples were analyzed in the laboratory. The parameters are porosity, permeability, hydrogen potential (pH), cation exchange capacity (CEC), soil organic matter (SOC), total-N (nitrogen), carbon/nitrogen (C/N) ratio, available-P (phosphorus), available-K (potassium), base saturation (BS), electric conductivity (EC), soil respiration (qCO2), redox potential (Eh) with 3 repetitions. The value of soil quality index (SQI) in the organic paddy field is 3.216 with bad soil quality criteria, while the non-organic paddy field is 0.147 with very bad criteria. The soil quality values are based on the key factors or MDS that is potential redox (EH), soil respiration (qCO2), potential hydrogen (pH), porosity, soil organic matter (SOC), total-N (nitrogen), C/N ratio, available-P (phosphorus).
Źródło:
Polish Journal of Soil Science; 2020, 53, 1; 81-95
0079-2985
Pojawia się w:
Polish Journal of Soil Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Korelacje między wybranymi zanieczyszczeniami w ściekach deszczowych
Correlation between selected pollutants in rainfall wastewater
Autorzy:
Górska, K.
Szeląg, B.
Górski, J.
Bąk, Ł.
Powiązania:
https://bibliotekanauki.pl/articles/125912.pdf
Data publikacji:
2014
Wydawca:
Towarzystwo Chemii i Inżynierii Ekologicznej
Tematy:
ścieki deszczowe
metale ciężkie
analiza składowych głównych
biplot
rainfall wastewater
heavy metals
principal component analysis
Opis:
W ostatnim okresie coraz częściej zwraca się uwagę na fakt, że zanieczyszczenia ścieków deszczowych to nie tylko definiowane odpowiednimi przepisami zawiesiny ogólne i związki ropopochodne, ale też inne związki mające wpływ na środowisko gruntowe i wody odbiornika. Należą do nich m.in. metale ciężkie, chlorki, siarczany, biogeny, zanieczyszczenia mikrobiologiczne. Zróżnicowanie czynników wpływających na jakość ścieków deszczowych, związanych między innymi z zanieczyszczeniem powietrza atmosferycznego czy rodzajem pokrycia terenu oraz prowadzonej działalności człowieka, powoduje, że określenie typowego ich składu jest zadaniem bardzo trudnym, szczególnie jeśli mamy do czynienia z terenami zurbanizowanymi. W rezultacie duże zanieczyszczenie wód opadowych odprowadzanych z terenów miejskich wpływa zdecydowanie na okresowe pogorszenie stanu czystości wód oraz destabilizuje równowagę biologiczną w odbiorniku. W artykule przedstawiono wyniki badań stanu zanieczyszczenia ścieków deszczowych spływających systemem kanalizacyjnym z obszaru wybranej zlewni o typowo miejskim charakterze, zlokalizowanej w centrum Kielc. Do analiz wytypowano wezbrania z okresu letniego i zimowego, w czasie których pobrano za pomocą automatycznego samplera próby ścieków deszczowych i roztopowych. Oznaczono w nich stężenia metali ciężkich (Ni, Cu, Cr, Zn, Pb, Cd), chlorków oraz określono pH i temperaturę. Do oceny korelacji między analizowanymi wskaźnikami zanieczyszczeń zastosowano metodę składowych głównych, a na tej podstawie sporządzono biploty oraz wyznaczono współrzędne czynnikowe.
Recently, increasing attention has been paid to the fact that the rainfall wastewater pollution is defined not only by the suspended solids and oil derivatives, the admissible levels of which are given in regulations, but also by other compounds that affect the soil environment and the waters of the receiver. Those include, among others, heavy metals, chlorides, sulphates, biogenic substances, and microbiological pollutants. The quality of rainfall wastewater is influenced, among others by atmospheric air pollution, type of terrain coverage, and human activity. Diversity of factors that affect the quality of rainfall wastewater is enormous, which makes it extremely difficult to determine a typical composition of such wastewater, especially in urbanised areas. As a result, high pollution of rainfall waters running off from urban areas has a decisive impact on periodic deterioration of water purity and it disturbs the biological balance in the receiver. The paper presents the results of investigations on the pollution of rainfall wastewater running off, through a sewer system, from the area of selected catchment, typically urban in character, located in the centre of Kielce. The analysis was conducted for high water stages occurring in summer and winter periods. Samples of rainfall and spring thaw wastewater were collected using an automatic sampler. Heavy metals (Ni, Cu, Cr, Zn, Pb, Cd) and chloride concentrations, pH and temperature were determined for those samples. To assess the correlation between analysed pollution indexes, the Principal Component Analysis was used, on the basis of which biplots were made and factor coordinates were determined.
Źródło:
Proceedings of ECOpole; 2014, 8, 2; 497-504
1898-617X
2084-4557
Pojawia się w:
Proceedings of ECOpole
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chemical composition and nutritional value of maize grains from cultivars of different breeding and seed companies
Skład chemiczny oraz wartość pokarmowa ziarna kukurydzy odmian różnych firm hodowlano-nasiennych
Autorzy:
Szulc, P.
Podkówka, Z.
Bocianowski, J.
Krauklis, D.
Wilczewska, W.
Powiązania:
https://bibliotekanauki.pl/articles/337591.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Maszyn Rolniczych
Tematy:
maize
grain
cultivars
nutritional value
principal component analysis
kukurydza
ziarno
odmiana
wartość odżywcza
analiza składników
Opis:
The study presents the results of field experiments aimed at assessing the level of yield, chemical composition and nutritive value of grain of 32 maize cultivars from different breeding and seed companies. The grain yield, grain chemical composition, fiber fraction content, grain nutritional value, thousand seed weight and grain density were determined to verify the adopted assumptions. The highest content of starch, total protein, fat and nitrogen-free extract compounds was found in the cultivars of the following companies: Limagrain, IGP, Saaten-Union and Maisadour, while the lowest in IGP, Maisadour, Limagrain and IGP, respectively. The energy value of 1 kg dry weight of maize grain for poultry ranged from 14.60 (Maisadour) to 15.22 MJ EM (IGP) and statistically significant differences in the concentration of metabolic energy for poultry was found only in the grain from these companies. Concentration of metabolic energy for pigs ranged from 15.79 (Limagrain) to 15.93 MJ (Saaten-Union) and statistically significant differences in the concentration of metabolic energy for pigs were recorded only in the grain from these companies. Grains from Saaten-Union had a higher concentration of net lactation energy than those from Limagrain and Maisadour. Crude protein, net energy of lactation, sugar, exhaust nitrogenless compounds, weight of one thousand seeds (WTS) and grain density influence on differentiation maize’s cultivars.
W pracy przedstawiono wyniki badań polowych, których celem była ocena poziomu plonowania, składu chemicznego oraz wartości pokarmowej ziarna 32 odmian kukurydzy różnych firm hodowlano-nasiennych. Celem weryfikacji przyjętych założeń określono plon ziarna, skład chemiczny ziarna, zawartość frakcji włókna, wartość pokarmową ziarna, masę tysiąca ziaren oraz gęstość ziarna. Największą zawartość skrobi, białka ogólnego, tłuszczu oraz związków bezazotowych wyciągowych stwierdzono w odmianach firm: Limagrain, IGP, Saaten-Union oraz Maisadour, natomiast najniższą odpowiednio w firmach IGP, Maisadour, Limagrain, IGP. Wartość energetyczna 1 kg suchej masy ziarna kukurydzy dla drobiu wahała się od 14,60 (Maisadour) do 15,22 MJ EM (IGP) i tylko w ziarnie pochodzącym z tych firm odnotowano różnice istotne statystycznie w koncentracji energii metabolicznej dla drobiu. Koncentracja energii metabolicznej dla świń wahała się od 15,79 (Limagrain) do 15,93 MJ (Saaten-Union) i tylko w ziarnie pochodzącym z tych firm odnotowano różnice istotne statystycznie w koncentracji energii metabolicznej dla świń. Ziarna z firmy Saaten-Union miały wyższą koncentrację energii netto laktacji niż z firmy Limagrain oraz Maisadour.
Źródło:
Journal of Research and Applications in Agricultural Engineering; 2018, 63, 4; 203-208
1642-686X
2719-423X
Pojawia się w:
Journal of Research and Applications in Agricultural Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of Statistical Features and Multilayer Neural Network to Automatic Diagnosis of Arrhythmia by ECG Signals
Autorzy:
Slama, A. B.
Lentka, Ł.
Mouelhi, A.
Diouani, M. F.
Sayadi, M.
Smulko, J.
Powiązania:
https://bibliotekanauki.pl/articles/221289.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Multilayer Neural Network
arrhythmia diagnosis
ECG signal processing
Principal Component Analysis
Fisher’s Linear Discriminant
Opis:
Abnormal electrical activity of heart can produce a cardiac arrhythmia. The electrocardiogram (ECG) is a non-invasive technique which is used as a diagnostic tool for cardiac diseases. Non-stationarity and irregularity of heartbeat signal imposes many difficulties to clinicians (e.g., in the case of myocardial infarction arrhythmia). Fortunately, signal processing algorithms can expose hidden information within ECG signal contaminated by additive noise components. This paper explores a method of de-noising ECG signal by the discrete wavelet transform (DWT) and further detecting arrhythmia by estimated statistical parameters. Parameters of the de-noised ECG signals were used to form an input data vector determining whether the examined patient suffers from a cardiac arrhythmia or not. Input data were transformed using selected linear methods in order to reduce dimension of the input vector. A neural network was used to detect illness. Compared with the results of recent studies, the proposed method provides more accurate diagnosis based on the examined ECG signal data.
Źródło:
Metrology and Measurement Systems; 2018, 25, 1; 87-101
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A principal component analysis in concrete design
Autorzy:
Kobaka, Janusz
Katzer, Jacek
Powiązania:
https://bibliotekanauki.pl/articles/31342619.pdf
Data publikacji:
2022
Wydawca:
Politechnika Częstochowska
Tematy:
principal component analysis
PCA
concrete designing
concrete mix
analiza głównych składowych
projektowanie betonu
mieszanka betonowa
Opis:
Over the last 200 years, ordinary concrete has evolved from four basic ingredient materials (gravel, sand, cement, and water) to multicomponent complex composites. The number and variety of the additives, admixtures, non-conventional aggregates, fillers, and fibres currently used for concrete production have continued to grow rapidly. Regrettably, the methods for de-signing concrete mixes have not evolved at a similarly fast pace. Keeping the above facts in mind, the authors utilised a principal component analysis (PCA) to design modern concrete mixes. As an initial approach, 550 cast and tested concrete mixes were analysed. The main aim of the presented study was to prove the usefulness of the PCA methodology for the fast classification of concrete mix compositions. The acquired knowledge should be useful for the effective design of multicomponent modern concrete mixes.
Źródło:
Budownictwo o Zoptymalizowanym Potencjale Energetycznym; 2022, 11; 203-219
2299-8535
2544-963X
Pojawia się w:
Budownictwo o Zoptymalizowanym Potencjale Energetycznym
Dostawca treści:
Biblioteka Nauki
Artykuł

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