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Tytuł:
Change Point Determination in Audio Data Using Auditory Features
Autorzy:
Maka, T.
Powiązania:
https://bibliotekanauki.pl/articles/226762.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
audio change point detection
auditory features
gammatone filter bank
Opis:
The study is aimed to investigate the properties of auditory-based features for audio change point detection process. In the performed analysis, two popular techniques have been used: a metric-based approach and the ∆BIC scheme. The efficiency of the change point detection process depends on the type and size of the feature space. Therefore, we have compared two auditory-based feature sets (MFCC and GTEAD) in both change point detection schemes. We have proposed a new technique based on multiscale analysis to determine the content change in the audio data. The comparison of the two typical change point detection techniques with two different feature spaces has been performed on the set of acoustical scenes with single change point. As the results show, the accuracy of the detected positions depends on the feature type, feature space dimensionality, detection technique and the type of audio data. In case of the ∆BIC approach, the better accuracy has been obtained for MFCC feature space in the most cases. However, the change point detection with this feature results in a lower detection ratio in comparison to the GTEAD feature. Using the same criteria as for ∆BIC, the proposed multiscale metric-based technique has been executed. In such case, the use of the GTEAD feature space has led to better accuracy. We have shown that the proposed multiscale change point detection scheme is competitive to the ∆BIC scheme with the MFCC feature space.
Źródło:
International Journal of Electronics and Telecommunications; 2015, 61, 2; 185-190
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
GNSS positioning error change-point detection in GNSS Positioning Performance Modelling
Autorzy:
Filić, M.
Filjar, R.
Powiązania:
https://bibliotekanauki.pl/articles/117469.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
Global Navigation Satellite System (GNSS)
positioning
Navigation and Timing (PNT)
GNSS Positioning Performance Modelling
GNSS Positioning Error Change-point Detection
GNSS Positioning Performance
GNSS Resilience
GNSS Utilisation Risk Mitigation
GNSS Positioning Performance Degradation
Opis:
Provision of uninterrupted and robust Positioning, Navigation, and Timing (PNT) services is essential task of Global Navigation Satellite Systems (GNSS) as an enabling technology for numerous technology and socio-economic applications, a cornerstone of the modern civilisation, a public goods, and an essential component of a national infrastructure. GNSS resilience may be accomplished only with complete understanding of the causes of GNSS positioning performance disruptions and degradations, presented in a form of applications- and scenarios-related models. Here the application of change-point detection methods is proposed and demonstrated in a selected scenario of a fast-developing ionospheric storm’s impact on GNSS positioning performance, as a novel contribution to forecasting GNSS positioning performance model development and GNSS utilisation risk mitigation.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2019, 13, 3; 575-579
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An Application of Bootstrapping for CUSUM Test in Mean Change-Point Model and Forecasting
Autorzy:
Rois, Rumana
Prima, Afsana Tasnim
Shanta, Munia Afroza
Powiązania:
https://bibliotekanauki.pl/articles/1075648.pdf
Data publikacji:
2019
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
AMOC model
CUSUM test
asymptotic critical value
bootstrap critical value
change-point
extreme value distribution
Opis:
Application of change-point analysis increases as more data sets are collected in a wide variety of fields. Detection of change-point is useful in modeling and prediction of time series, especially, it has a significant impact on forecasting. The critical value of a test is required to conduct that test in detecting change-point. The calculation of the critical values is based on the distributional asymptotics of the test statistics under the null hypothesis. Cumulative sum (CUSUM) test is a popular change-point test in location model. The convergence of the limit distribution of the CUSUM test statistic is rather slow. Antoch and Hušková (2001) suggested that the critical value of the permutation test, a test based on the bootstrap principle, performs better than the asymptotic critical value of CUSUM test in location model. Inspired by them, we consider a change in the mean with i.i.d. errors to evaluate the performance of the bootstrap and the asymptotic critical values of CUSUM test to the simulated and real data. We used the monthly average rainfall in Cumilla, a district in Bangladesh, from 1948 to 2013 as a real data. We also motivated to develop a forecasting model taking into accout of the detected change-point. The result demonstrates that the performance of the bootstrap critical value of CUSUM test is better than the asymptotic one for both the simulated and real data. Moreover, the accuracy of the monthly average rainfall forecasting in Cumilla is improved by considering the valid change-point in modeling.
Źródło:
World Scientific News; 2019, 125; 217-229
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Identification of the change-point of a distribution in a sequence of random variables
Autorzy:
Schulze, U.
Powiązania:
https://bibliotekanauki.pl/articles/748634.pdf
Data publikacji:
1986
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
Research exposition
Bayesian problems
Hypothesis testing
Point estimation
Opis:
Artykuł nie zawiera streszczenia
The article contains no abstract
Źródło:
Mathematica Applicanda; 1986, 14, 28
1730-2668
2299-4009
Pojawia się w:
Mathematica Applicanda
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Global and local trend analysis and change-point analysis of selected financial and market indices
Autorzy:
Ballova, Dominika
Powiązania:
https://bibliotekanauki.pl/articles/384353.pdf
Data publikacji:
2019
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Tematy:
trend analysis
change-point analysis
cluster analysis
Opis:
From the macroeconomic point of view, the stock index is the best indicator of the behavior of the stock market. Stock indices fulfill different functions. One of their most important functions is to observe developments of the stock market situation. Therefore, it is crucial to describe the long-term development of indices and also to find moments of abrupt changes. Another interesting aspect is to find those indices that have evolved in a similar way over time. In this article, using trend analysis, we will uncover the global evolution of selected indices. After evaluating the global trend in the series we compare the results with local trend analysis. Other goal is to detect the moments in which this development suddenly changed using the change-point analysis. By means of cluster analysis, we find those indices that are most similar in long-term development. In each analysis, we select the most appropriate methods and compare their results.
Źródło:
Journal of Automation Mobile Robotics and Intelligent Systems; 2019, 13, 3; 56-63
1897-8649
2080-2145
Pojawia się w:
Journal of Automation Mobile Robotics and Intelligent Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the choice of parameters of change-point detection with application to stock exchange data
Autorzy:
Jaworski, Stanisław
Furmańczyk, Konrad
Powiązania:
https://bibliotekanauki.pl/articles/453355.pdf
Data publikacji:
2011
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Katedra Ekonometrii i Statystyki
Tematy:
V-Box Chart
mini-max rule, normal
distribution
Opis:
Our paper is devoted to the study of V-Box Chart method in a parametric model. This algorithm is proposed to be used in the change-point detection in a sequence of observations. The choice of parameters in such an algorithm is heuristic. In our paper we use the mini-max rule for this choice and we control the probability that no signal is given, when the process is out of control as well as the probability of false alarm. We apply this algorithm to the detection of a change in stock exchange data.
Źródło:
Metody Ilościowe w Badaniach Ekonomicznych; 2011, 12, 1; 87-96
2082-792X
Pojawia się w:
Metody Ilościowe w Badaniach Ekonomicznych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Semi-parametric modification of cumulative sum algorithms for the change-point detection of non-Gaussian sequences
Autorzy:
Zabolotnii, S. W
Warsza, Z. L.
Powiązania:
https://bibliotekanauki.pl/articles/114188.pdf
Data publikacji:
2015
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
change point
CUSUM algorithm
non-Gaussian sequence
stochastic polynomial
high order statistics
Opis:
The expansion of logarithm likelihood ratio in the stochastic series to find the sequential change-point detection of non-Gaussian sequences is used. The moment criteria of the minimum of upper limit error probabilities sum to find the expansion coefficients is applied. The proposed method is a semi-parametric type of cumulative sum (CUSUM) algorithm which needs of higher-order statistics. Results show that polynomial algorithms are more effective in comparison with similar non-parametric procedures.
Źródło:
Measurement Automation Monitoring; 2015, 61, 12; 532-534
2450-2855
Pojawia się w:
Measurement Automation Monitoring
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Change-point detection in CO2 emission-energy consumption nexus using a recursive Bayesian estimation approach
Autorzy:
Awe, Olushina Olawale
Adepoju, Abosede Adedayo
Powiązania:
https://bibliotekanauki.pl/articles/1358349.pdf
Data publikacji:
2020-03-23
Wydawca:
Główny Urząd Statystyczny
Tematy:
dynamic model
Bayesian inference
CO2
climate change
energy
Opis:
This article focuses on the synthesis of conditional dependence structure of recursive Bayesian estimation of dynamic state space models with time-varying parameters using a newly modified recursive Bayesian algorithm. The results of empirical applications to climate data from Nigeria reveals that the relationship between energy consumption and carbon dioxide emission in Nigeria reached the lowest peak in the late 1980s and the highest peak in early 2000. For South Africa, the slope trajectory of the model descended to the lowest in the mid-1990s and attained the highest peak in early 2000. These changepoints can be attributed to the economic growth, regime changes, anthropogenic activities, vehicular emissions, population growth and industrial revolution in these countries. These results have implications on climate change prediction and global warming in both countries, and also shows that recursive Bayesian dynamic model with time-varying parameters is suitable for statistical inference in climate change and policy analysis.
Źródło:
Statistics in Transition new series; 2020, 21, 1; 123-136
1234-7655
Pojawia się w:
Statistics in Transition new series
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Physiological background of the change point in VO2 and the slow component of oxygen uptake kinetics
Autorzy:
Zoladz, J.A.
Korzeniewski, B.
Powiązania:
https://bibliotekanauki.pl/articles/69946.pdf
Data publikacji:
2001
Wydawca:
Polskie Towarzystwo Fizjologiczne
Tematy:
muscle fatigue
acid-base status
kinetics
exercise
respiratory muscle
oxygen uptake
Źródło:
Journal of Physiology and Pharmacology; 2001, 52, 2
0867-5910
Pojawia się w:
Journal of Physiology and Pharmacology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
About robust detection of a breakdown point in selected linear regression models
O odpornym wykrywaniu punktu zmiany tendencji w wybranych modelach regresji liniowej
Autorzy:
Kosiorowski, Daniel
Powiązania:
https://bibliotekanauki.pl/articles/907040.pdf
Data publikacji:
2008
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
change-point
regression depth
schwarz information criterion
Opis:
In this paper an approach appealing to a regression depth concept is applied to a robust detection of points (moments) of a regression coefficients change. The propositions are compared with propositions based on Schwarz information criterion and discussed in the context of linear mixed models.
W referacie przedstawiamy pewne propozycje dotyczące odpornego wykrywania punktu (chwili), w którym następuje zmiana współczynników regresji liniowej. Propozycje odwołują się do koncepcji głębi regresyjnej przedstawionej przez Rousseeuw i Hubert (1998). Własności proponowanego podejścia porównujemy z podejściem wykorzystującym kryterium informacyjne Schwarza oraz dyskutujemy je w kontekście liniowych modeli mieszanych.
Źródło:
Acta Universitatis Lodziensis. Folia Oeconomica; 2008, 216
0208-6018
2353-7663
Pojawia się w:
Acta Universitatis Lodziensis. Folia Oeconomica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Advanced methods of earnings management: monotonic trends and change-points under spotlight in the Visegrad countries
Autorzy:
Kliestik, Tomas
Valaskova, Katarina
Nica, Elvira
Kovacova, Maria
Lazaroiu, George
Powiązania:
https://bibliotekanauki.pl/articles/19233520.pdf
Data publikacji:
2020
Wydawca:
Instytut Badań Gospodarczych
Tematy:
business finance
change-point
earnings management
monotonic trend
European countries
Opis:
Research background: Enterprises manage earnings in an effort to balance their profit fluctuations to provide increasingly consistent earnings in every reporting period. Earnings management is legal and very effective method of accounting techniques and may be used to obtain specific objectives of the enterprises involving the manipulation of accruals. Therefore, there is a need to analyze it in the context of group of countries, while the issue of their detection in the new ways appears.  Purpose of the article: The analysis of annual earnings before interest and taxes (EBIT) of 5,640 enterprises from the Visegrad Four during the period 2009-2018 confirms that the development of earnings management in these countries is not a randomness. Thus, the aim of this article is to determine the existence of positive trend in earnings management and to detect the change-point in its development for each Visegrad country. Methods: Grubbs test, Mann-Kendall trend test and Buishand test were used as appropriate statistical methods. Mann-Kendall test identifies significant monotonic trend occurrence in earnings manipulation in every country. Buishand test indicates significant years, which divides the development of EBIT into two homogenous groups with individual central lines. Findings & Value added: Based on the statistical analysis applied, we rejected randomness in the managing of earning, but we determined the trend of its increasing. The positive earnings manipulation was not homogenous in the analyzed period, however, a change-point was defined. Year 2014 was identified as a break-point for Slovak, Polish and Hungarian enterprises considering the earnings manipulation. Year 2013 was detected as a change-point in Czech enterprises. The methodical approach used may be very helpful for researchers from other countries to determine, detect and understand earnings management as well as for the investors to make decisions based on a specificities of an individual country.
Źródło:
Oeconomia Copernicana; 2020, 11, 2; 371-400
2083-1277
Pojawia się w:
Oeconomia Copernicana
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Bayesian significance test of change for correlated observations
Autorzy:
Slama, Abdeldjalil
Powiązania:
https://bibliotekanauki.pl/articles/729738.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
autoregressive model
change point
HPD region sets
p-value
Gibbs sampler
Opis:
This paper presents a Bayesian significance test for a change in mean when observations are not independent. Using a noninformative prior, a unconditional test based on the highest posterior density credible set is determined. From a Gibbs sampler simulation study the effect of correlation on the performance of the Bayesian significance test derived under the assumption of no correlation is examined. This paper is a generalization of earlier studies by KIM (1991) to not independent observations.
Źródło:
Discussiones Mathematicae Probability and Statistics; 2014, 34, 1-2; 51-62
1509-9423
Pojawia się w:
Discussiones Mathematicae Probability and Statistics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Change-point detection and trend analysis in monthly, seasonal and annual air temperature and precipitation series in Bartın province in the western Black Sea region of Turkey
Autorzy:
Yaman, Barbaros
Ertuğrul, Mertol
Powiązania:
https://bibliotekanauki.pl/articles/1841778.pdf
Data publikacji:
2020
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
climate change
homogeneity
precipitation
temperature
trend analysis
Opis:
Studies associated with climate change and variability are of great importance at both the global and local scale in the global climate crisis. In this study, change-point detection and trend analysis were carried out on mean, maximum, minimum air temperatures and total precipitation based on monthly, seasonal and annual scale in Bartın province located in the western Black Sea Region of Turkey. For this aim, 4-different homogeneity tests (von Neumann test, Pettitt test, Buishand range test and standard normal homogeneity test) for changepoint detection, Modified Mann–Kendall test and Şen’s innovative trend test for trend analysis, and Sen’s slope test for the magnitude estimation of trends were used. According to the test results, the summer temperatures in particular show increasing trends at the 0.001 significance level. Mean maximum temperature in August, mean minimum temperature in June and August, and mean temperature in July and August are in increasing trend at the 0.001 significance level. Over a 51 year period (1965–2015) in Bartın province, the highest rate of change per decade in air temperatures is in August (0.55°C for Tmax, 0.46°C for Tmin and 0.43°C for Tmean) based on Sen’s slope. However, the study showed that apart from October precipitation, there is no significant trend in monthly, seasonal and annual precipitation in Bartın. Increasing trends in mentioned climate variables are also visually very clear and strong in Şen’s innovative trend method, and they comply with the statistical results. As a result, the study revealed some evidence that temperatures will increase in the future in Bartın and its environs.
Źródło:
Geology, Geophysics and Environment; 2020, 46, 3; 223-237
2299-8004
2353-0790
Pojawia się w:
Geology, Geophysics and Environment
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Distribution Approximations for Cusum and Cusumsq Statistics
Autorzy:
Habibi, Reza
Powiązania:
https://bibliotekanauki.pl/articles/465719.pdf
Data publikacji:
2010
Wydawca:
Główny Urząd Statystyczny
Tematy:
Beta approximated
Change point
Cumulative sum
Cumulative sum of squares Multivariate normal
Response surface regression
Opis:
The cumulative sum (cusum) is an important statistics in testing for a change point. This paper is concerned with the distribution approximations to the cusum statistic under the null and alternative hypotheses. We also consider distribution approximations for the cumulative sum of squares (cusumsq) test statistics. Finally, a discussion section is given.
Źródło:
Statistics in Transition new series; 2010, 11, 3; 158-168
1234-7655
Pojawia się w:
Statistics in Transition new series
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On a book 'Financial statistics and mathematical finance. Methods, models and applications.' by Ansgar Steland
Autorzy:
Szajowski, Krzysztof J.
Powiązania:
https://bibliotekanauki.pl/articles/747467.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
Applications of statistics
Actuarial sciences
Financial mathematics
Statistical methods in mathematical finance
Econometrics
Change point detection
Opis:
This book presents a careful and comprehensive introduction to some of the most important mathematical topics required for a thorough understanding of financial markets and the quantitative methods used to manage the assets there. The author has focused on arbitrage theory for pricing contingent claims and  statistical models and methods to analyze data from financial markets. It is quit new idea to combine the data analysis methods for mathematical models of founds, options and other derivatives. In contrast to other studies devoted to the modeling of economic phenomena can be found in the reflection of the author's experience in the study of phenomena on the capital markets. Particularly valuable are the chapters that are not in the understanding of other specialists and for special statistical procedures as the basis for the creation of methods of technical analysis trading on financial markets. The results are provided in detail, although usually not in their most general form. The presentation allows for relatively easy to learn the basic techniques of modeling for those coming to the subject for the first time. This effect is get by keeping  notations as elementary as possible. Each part of material is enriched with notes and comments on selected references, which may complement the presented material.  It is addressed to interdisciplinary graduate/undergraduate students and to interdisciplinary young researchers. Some chapters are available to Bachelor students who have passed introductory courses in probability calculus and statistics.
Źródło:
Mathematica Applicanda; 2016, 44, 2
1730-2668
2299-4009
Pojawia się w:
Mathematica Applicanda
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ocean fronts detection over the Bay of Bengal using changepoint algorithms - A non-parametric approach
Autorzy:
Reddem, V.S.
Muthalagu, R.
Bekkam, V.R.
Eluri, P.R.R.
Jampana, V.
Nimit, K.
Powiązania:
https://bibliotekanauki.pl/articles/2078823.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
ocean front
detection
satellite image
change point analysis
algorithm
advanced very high resolution radiometer
Bengal Bay
Opis:
Oceanic fronts are regions over the oceans where a significant change in the characteristics of the water masses is observed. Advanced Very High Resolution Radiometer (AVHRR) satellite imagery over the Bay of Bengal shows regions that are populated by frontal structures. Over the Bay of Bengal, some of the strongest gradients in temperature and salinity are observed. In recent years, there has been a tremendous growth in the availability of satellite imagery and the necessity of automated fast detection of the frontal features is needed for services like potential fishing zones over open oceans. In this article, an algorithm to infer oceanic fronts over the Bay of Bengal is described using changepoint analysis. The changepoint algorithm is combined in a novel way with a contextual median filter to detect frontal features in AVHRR imagery. The changepoint analysis is a non-parametric technique that does not put thresholds on the gradients of brightness temperatures of the satellite imagery. In the open oceans, the gradients of temperature and salinity are not sharp and changepoint analysis is found to be a useful complementary technique to the existing front detecting methods when combined with contextual median filters.
Źródło:
Oceanologia; 2021, 63, 4; 438-477
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wstępna analiza parametrów termicznych zestawu szybowego wypełnionego materiałem fazowo zmiennym
Preliminary analysys of the thermal properties of glazing unit filled with phase change material
Autorzy:
Wieprzkowicz, A.
Heim, D.
Powiązania:
https://bibliotekanauki.pl/articles/362453.pdf
Data publikacji:
2017
Wydawca:
Instytut Fizyki Budowli Katarzyna i Piotr Klemm
Tematy:
promieniowanie słoneczne
przemiana fazowa
temperatury przemian
magazynowanie ciepła
dynamika cieplna
solar radiation
phase transformation
change point
heat storage
thermal dynamics
Opis:
W pracy przedstawiono wyniki analiz numerycznych dynamiki cieplnej wybranych rodzajów oszklenia modyfikowanych materiałem fazowo-zmiennym (MFZ). Analizy wykonano dla dwóch zestawów danych meteorologicznych, charakterystycznych dla klimatu umiarkowanego oraz podzwrotnikowego oraz trzech orientacji przegrody względem stron świata. W zależności od lokalizacji zdefiniowano 2 rozwiązania techniczne przegrody. Zaproponowano 3 kryteria determinujące żądane temperatury przemiany fazowej MFZ wypełniającego jedną z przestrzenni międzyszybowych. Na podstawie wyników analiz numerycznych wyznaczono wymagane temperatury oraz dobrano dostępne materiały z grupy parafin. Wybrane materiały stanowią niskotemperaturowe magazyny ciepła w zakresie temperatur przemiany 18-21°C w przypadku doboru dla okresu zimowego oraz 25-31°C (35°C dla Santiago) w przypadku analiz przeprowadzonych dla lata.
The paper presents results of numerical analysis of thermal dynamics of selected types of glazing modified with phase-change material (PCM). The analyzes were performed for two sets of meteorological data, typical for the moderate and subtropical climate, and the three orientations of façade. Depending on the location, two technical solutions were defined. Three criteria have been proposed to determine the most efficient phase transition temperature of PCM filling one of the window cavities. Based on the results of numerical analysis, the required temperatures were determined and materials from the paraffin group were selected. Selected materials are low temperature heat stores with a transition temperature of 18-21°C for winter season and 25-31°C (35°C for Santiago) for summer analyzes.
Źródło:
Fizyka Budowli w Teorii i Praktyce; 2017, T. 9, nr 1, 1; 39-44
1734-4891
Pojawia się w:
Fizyka Budowli w Teorii i Praktyce
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spatio-temporal analysis of rainfall trends in Chhattisgarh State, Central India over the last 115 years
Przestrzenna i czasowa analiza tendencji zmian opadów w stanie Chhattisgarh w środkowych Indiach w ciągu ostatnich 115 lat
Autorzy:
Nema, M. K.
Khare, D.
Adamowski, J.
Chandniha, S. K.
Powiązania:
https://bibliotekanauki.pl/articles/292272.pdf
Data publikacji:
2018
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
change point
gridded data
modified Mann–Kendall test
rainfall variability
trend analysis
analiza trendu
dane gridowe
punkt zwrotny
zmienność opadów
zmodyfikowany test Manna– Kendalla
Opis:
A quantitative and qualitative understanding of the anticipated climate-change-driven multi-scale spatio- -temporal shifts in precipitation and attendant river flows is crucial to the development of water resources management approaches capable of sustaining and even improving the ecological and socioeconomic viability of rainfed agricultural regions. A set of homogeneity tests for change point detection, non-parametric trend tests, and the Sen’s slope estimator were applied to long-term gridded rainfall records of 27 newly formed districts in Chhattisgarh State, India. Illustrating the impacts of climate change, an analysis of spatial variability, multitemporal (monthly, seasonal, annual) trends and inter-annual variations in rainfall over the last 115 years (1901– 2015 mean 1360 mm·y–1) showed an overall decline in rainfall, with 1961 being a change point year (i.e., shift from rising to declining trend) for most districts in Chhattisgarh. Spatio-temporal variations in rainfall within the state of Chhattisgarh showed a coefficient of variation of 19.77%. Strong inter-annual and seasonal variability in regional rainfall were noted. These rainfall trend analyses may help predict future climate scenarios and thereby allow planning of effective and sustainable water resources management for the region.
Ilościowe i jakościowe rozpoznanie przewidywanych wielowymiarowych zmian opadów i towarzyszących im przepływów w rzekach spowodowanych zmianami klimatu jest decydujące dla rozwoju metod zarządzania zasobami wodnymi zdolnych utrzymać lub nawet usprawnić rentowność obszarów rolniczych zasilanych opadami. Zastosowano kilka testów jednorodności do wykrycia punktu zwrotnego, nieparametryczne testy trendu i estymator nachylenia Sena do analizy wieloletnich danych o opadach w 27 nowo utworzonych dystryktach stanu Chhattisgarh w Indiach. Ilustrując wpływ zmian klimatu, wyniki analizy przestrzennej zmienności, miesięcznych, sezonowych i rocznych trendów oraz zmienności między latami (1901–2015, średni opad 1360 mm·r–1) wykazały ogólne zmniejszenie ilości opadów w większości dystryktów stanu Chhattisgarh. Rok 1961 był punktem zwrotnym między rosnącym a malejącym trendem opadów. Współczynnik zmienności przestrzennej i czasowej opadów w stanie Chhattisgarh wynosił 19,77%. Zanotowano znaczną zmienność opadów między poszczególnymi latami i porami roku. Takie analizy trendów mogą być przydatne w przewidywaniu przyszłych scenariuszy klimatycznych, a w związku z tym – umożliwić wydajne i zrównoważone zarządzanie zasobami wodnymi regionu.
Źródło:
Journal of Water and Land Development; 2018, 36; 117-128
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The concepts of Ludwik Fleck and their application to the eukaryotic cell cycle
Koncepcje Ludwika Flecka i ich zastosowanie do eukariotycznego cyklu komórkowego
Autorzy:
Stephen, Cooper
Powiązania:
https://bibliotekanauki.pl/articles/783471.pdf
Data publikacji:
2017-12-18
Wydawca:
Polska Akademia Umiejętności
Tematy:
Ludwik Fleck
G0
G1
Restriction Point
Rate-Change Point
Eukaryotic Cell Cycle
Gene Expression in Cell Cycle
punkt restrukcyjny
punkt zmiany tempa wzrostu
eukariotyczny cykl komórkowy
ekspresja genu w cyklu komórkowym
Opis:
The concepts of Ludwik Fleck (1896–1961), a microbiologist, historian, and philosopher of medicine, can be used to analyze the conservative nature of scientific ideas. This is discussed and applied to ideas dominant in the understanding of the eukaryotic cell cycle. These are (a) the G1-phase restriction point as a regulatory element of the mammalian cell cycle, (b) the Rate Change Point proposed to exist in fission yeast, and (c) the proposal that a large number of genes are expressed in a cell-cycle-dependent manner. Fleck proposed that scientific ideas become fixed and difficult to change because criticisms of current and dominant models are either ignored or turned to support of the current model. The idea of a thought-collective leading to the stability of scientific ideas is a central theme of the theory of Ludwik Fleck.
Koncepcje Ludwika Flecka (1896–1961), mikrobiologa, historyka i filozofa medycyny, mogą być użyte do analizowania zjawiska skostnienia idei naukowych. Zagadnienie to omówiono i zastosowano do dominujących koncepcji w rozumieniu cyklu podziału komórek eukariotycznych. Są to: (a) punkt kontrolny fazy G1 (tzw. punkt restrykcyjny) jako element regulacyjny cyklu komórkowego u ssaków; (b) punkt zmiany tempa wzrostu komórek mający występować u drożdży rozszczepkowych (Schizosaccharomyces pombe) oraz (c) postulat, że ekspresja znacznej liczby genów jest zależna od fazy cyklu komórkowego. Fleck zaproponował, że idee naukowe utrwalają się i trudno je zmienić, ponieważ krytyka aktualnych i dominujących modeli jest albo ignorowana, albo przemieniana na poparcie aktualnie obowiązującego modelu. Idea „kolektywu myślowego”, prowadząca do stabilizacji idei naukowych, jest centralnym tematem teorii Ludwika Flecka.
Źródło:
Studia Historiae Scientiarum; 2017, 16; 335-364
2451-3202
Pojawia się w:
Studia Historiae Scientiarum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Résistance des corpus longs et déplacements de la recherche: l’exemple de la rédaction conversationnelle
Difficulties with a long corpus and the change of the point of gravity in studies: an-example of editing a text in the conversational interaction
Autorzy:
De Gaulmyn, Marie-Madeleine
Powiązania:
https://bibliotekanauki.pl/articles/1053392.pdf
Data publikacji:
2007-12-01
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Opis:
In this article the author presents an analysis of empirical material which consists of a recording of interaction between two female students as they edit together a written text on the subject given them. Various characteristics of these students (nationality, social status, upbringing, their past school experiences) cause conflicts which have not been predicted by the researcher and which influence the final form of the text being edited.
Źródło:
Studia Romanica Posnaniensia; 2000, 25; 109-124
0137-2475
2084-4158
Pojawia się w:
Studia Romanica Posnaniensia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Norwegian Tax System from the Point of View of Climate Change Policy
Autorzy:
Ptak, Michał
Powiązania:
https://bibliotekanauki.pl/articles/517351.pdf
Data publikacji:
2014
Wydawca:
Instytut Badań Gospodarczych
Tematy:
climate change policy
taxes
Norway
Opis:
Norway was the first country in the world to fix a carbon dioxide target. Norway was also one of the first countries to implement taxes to increase incentives to reduce greenhouse gas emissions. The aim of the paper is to analyse the role of environmental taxes in Norwegian climate policy. The author also examines the differences between the climate change policy measures in Norway and in the European Union countries, especially Poland.The first part of the paper contains an analysis of data on greenhouse gas emissions in Norway in the years 1990-2011. In the further sections of the paper the discussion is focused on the characteristics of Norwegian tax system and design of taxes used in Norway as instruments for addressing climate change. Particular attention is paid to the carbon tax, in force since 1991. The tax is responsible for large CO2 emission reductions. The paper is largely based on review of various reports, literature and websites on climate change policy, energy policy and transport policy in Norway.
Źródło:
Equilibrium. Quarterly Journal of Economics and Economic Policy; 2014, 9, 1; 71-89
1689-765X
2353-3293
Pojawia się w:
Equilibrium. Quarterly Journal of Economics and Economic Policy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bayesian analysis of structural change in a distributed Lag Model (Koyck Scheme)
Autorzy:
Sumobay, Arvin
Supe, Arnulfo
Powiązania:
https://bibliotekanauki.pl/articles/729762.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
distributed lag model
posterior distribution
break point
Opis:
Structural change for the Koyck Distributed Lag Model is analyzed through the Bayesian approach. The posterior distribution of the break point is derived with the use of the normal-gamma prior density and the break point, ν, is estimated by the value that attains the Highest Posterior Probability (HPP). Simulation study is done using R.
Given the parameter values ϕ = 0.2 and λ = 0.3, the full detection of the structural change when σ² = 1 is generally attained at ν + 1. The after one lag detection is due to the nature of the model which includes lagged variable. The interval estimate HPP near ν consistently and efficiently captures the break point ν in the interval HPPₜ ± 5% of the sample size. On the other hand, the detection of the structural change when σ² = 2 does not show any improvement of the point estimate of the break point ν.
Źródło:
Discussiones Mathematicae Probability and Statistics; 2014, 34, 1-2; 113-126
1509-9423
Pojawia się w:
Discussiones Mathematicae Probability and Statistics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Differential equation of transverse vibrations of a beam with a local stroke change of stiffness
Autorzy:
Kasprzyk, S.
Wiciak, M.
Powiązania:
https://bibliotekanauki.pl/articles/255492.pdf
Data publikacji:
2007
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
equation of a beam
joint point
distribution
Opis:
The aim of this paper is to derive a differential equation of transverse vibrations of a beam with a local, stroke change of stiffness, and to solve it. The presented method is based on the theory of distributions.
Źródło:
Opuscula Mathematica; 2007, 27, 2; 245-252
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
“From the Speaker’s Point of View” – Subjectification as Pragmatic-Semantic Language Change
Autorzy:
Pastuch, Magdalena
Powiązania:
https://bibliotekanauki.pl/articles/52921266.pdf
Data publikacji:
2023
Wydawca:
Uniwersytet Jagielloński. Wydawnictwo Uniwersytetu Jagiellońskiego
Tematy:
diachrony
history of the Polish language
language change
historical pragmatics
subjectification
metatextual expressions
Opis:
The article demonstrates the importance of subjectification processes in shaping the metatextual layer of language. Using three lexical units (prawda ‘true, right’, pewnie ‘sure, certainly’ and szalenie ‘extremely, madly’) as examples, the author shows how the enrichment of their semantic structure with a subjective component led to the emergence of new propositional functions and ultimately to the establishment of a new meaning. The study is conducted diachronically, drawing on the oldest attestations of the lexemes in question. Based on a contextual analysis, the moment the meanings with a subjective component appeared is identified. The results unequivocally demonstrate that subjectification has its origin in the pragmatic domain, while its consequences are visible on the semantic level. The language material comes from both lexicographic sources and corpora. The analysis shows that subjectification is correlated with formal changes including loss of inflectional endings, loss of morphological properties, recategorization, and syntactic isolation. The paper provides evidence for the need for in-depth comparative diachronic research on subjectification.
Źródło:
Studies in Polish Linguistics; 2023, 18, 4; 145-167
1732-8160
2300-5920
Pojawia się w:
Studies in Polish Linguistics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Output signal change analysis of an uncooled microbolometer focal plane array with respect to varying control voltages and operating point temperature
Autorzy:
Ligienza, A.
Bieszczad, G.
Sosnowski, T.
Gogler, S.
Krupiński, M.
Firmanty, K.
Powiązania:
https://bibliotekanauki.pl/articles/114040.pdf
Data publikacji:
2018
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
Focal Plane Array
microbolometer
Opis:
This paper presents results of output signal analysis of uncooled microbolometric focal plane array FPA. The analysis focuses on detectors manufactured by ULIS. The signal has been tested against varying control voltages, it is blind microbolometer biasing VSK and active microbolometer biasing VFID. The working point temperature of the environment was also altered in range from 5°C to 60°C. Such analysis can be used to check the results against current mathematical model of FPA’s behavior and verify validity of the measurement method in varying working conditions. Later it could allow explore possibility to design corrective algorithms.
Źródło:
Measurement Automation Monitoring; 2018, 64, 4; 95-98
2450-2855
Pojawia się w:
Measurement Automation Monitoring
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Relationships of Texture and Hydrophysical Properties in Soil Profiles Under Selected Exotic Trees in the Context of Climate Change in Central Europe
Autorzy:
Polláková, Nora
Šimanský, Vladimír
Jonczak, Jerzy
Powiązania:
https://bibliotekanauki.pl/articles/1838319.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
available water
drought
porosity
soil aeration
soil texture
wilting point
Opis:
Suitable soil and environmental conditions are the main prerequisites for successful growth of plants. Generally, all soil properties are substantially affected by textural composition. Therefore, the objective of the study was to test the interrelationships between particle size distribution and such physical soil properties, which usually predetermine the survival/death of plants, since they significantly affect the content and availability of water and air. Textural composition and physical soil properties were studied in profiles under monocultures of selected exotic trees in Arboretum Mlyňany, Slovakia. The results showed that medium-textured dominated in topsoils, whereas heavy-textured classes were dominant in luvic and stagnic horizons. Evaluation of entire profiles had confirmed standard, expected relationships between the individual grain fractions and soil physical properties. However, differences have occurred when the correlations between texture and physical properties in individual horizons were evaluated. Considering entire soil profiles, increased sand content significantly supported drainage of rainwater and soil aeration; silt contributed to increase the total porosity and aeration as well as available water capacity; clay contributed to the decrease in the available water capacity, total, and particularly coarse porosity and aeration, and to rise water retention, as well as the values of the wilting point. The results showed silt as key fraction providing suitable hydrophysical properties for the survival and growth of trees introduced in Arboretum. In compacted luvic and stagnic horizons, silt was significantly involved in the formation of total, and particularly coarse porosity and thereby increase soil aeration, while conversely, in loose topsoils just silt fraction significantly contributed to the reduction of coarse pores and increase of fine capillary pores and therefore water retention. In loose eluvial horizons, the silt contributed to significant increases in capillary porosity and water availability, which is essential in terms of meeting the plant needs.
Źródło:
Journal of Ecological Engineering; 2021, 22, 6; 244-252
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Relationships of Texture and Hydrophysical Properties in Soil Profiles Under Selected Exotic Trees in the Context of Climate Change in Central Europe
Autorzy:
Polláková, Nora
Šimanský, Vladimír
Jonczak, Jerzy
Powiązania:
https://bibliotekanauki.pl/articles/1838349.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
available water
drought
porosity
soil aeration
soil texture
wilting point
Opis:
Suitable soil and environmental conditions are the main prerequisites for successful growth of plants. Generally, all soil properties are substantially affected by textural composition. Therefore, the objective of the study was to test the interrelationships between particle size distribution and such physical soil properties, which usually predetermine the survival/death of plants, since they significantly affect the content and availability of water and air. Textural composition and physical soil properties were studied in profiles under monocultures of selected exotic trees in Arboretum Mlyňany, Slovakia. The results showed that medium-textured dominated in topsoils, whereas heavy-textured classes were dominant in luvic and stagnic horizons. Evaluation of entire profiles had confirmed standard, expected relationships between the individual grain fractions and soil physical properties. However, differences have occurred when the correlations between texture and physical properties in individual horizons were evaluated. Considering entire soil profiles, increased sand content significantly supported drainage of rainwater and soil aeration; silt contributed to increase the total porosity and aeration as well as available water capacity; clay contributed to the decrease in the available water capacity, total, and particularly coarse porosity and aeration, and to rise water retention, as well as the values of the wilting point. The results showed silt as key fraction providing suitable hydrophysical properties for the survival and growth of trees introduced in Arboretum. In compacted luvic and stagnic horizons, silt was significantly involved in the formation of total, and particularly coarse porosity and thereby increase soil aeration, while conversely, in loose topsoils just silt fraction significantly contributed to the reduction of coarse pores and increase of fine capillary pores and therefore water retention. In loose eluvial horizons, the silt contributed to significant increases in capillary porosity and water availability, which is essential in terms of meeting the plant needs.
Źródło:
Journal of Ecological Engineering; 2021, 22, 6; 244-252
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Utilizing crash and violation data to assess unsafe driving actions
Autorzy:
Rezapour Mashhadi, M. M.
Wulff, S. S.
Ksaibati, K.
Powiązania:
https://bibliotekanauki.pl/articles/2140833.pdf
Data publikacji:
2017
Wydawca:
Fundacja Centrum Badań Socjologicznych
Tematy:
No Improper driving
improper lane change
drive too fast for conditions
violation
citation
enforcement
Traffic Safety
road safety
Multinomial logistic regression
vehicle maneuver
point of impact
Opis:
Wyoming has one of the highest crash rates in the United States and a higher fatality rate than the U.S. average. These high rates result from many factors such as the high traffic through I-80 and the mountainous areas of Wyoming. This study employed two approaches to study contributory factors to crashes in the most hazardous interstate, I-80, in Wyoming by employing crash and citation data sets. Different factors may contribute to different driver actions so it is important to consider these crash causes separately. Thus, multiple logistic regression models were used in this study to examine the differences in crash-contributing factors for three driver actions: driving too fast for conditions, improper lane change, and no improper driving. These driver actions account for about 70% of all the crash causes on this interstate. The same violations as the two driver actions, improper lane change and driving too fast for conditions, account for 42% of all the crashes. The literature has indicated that previous violations can be used to predict future violations, and consequently crashes. Therefore, these violations were identified to detect the groups that are at higher risk of involvement in crashes. The analyses indicated that there are substantial differences across different driver actions for crash and violation data. For instance, not-dry-surface conditions increased the estimated odds of driving too fast for conditions 33 times while it decreased the risk of no improper driving by an estimated 250%. Crash severity, number of vehicles, vehicle maneuver, point of impact, driver condition, and speed compliance also impacted different driver actions differently. The results of violation analyses revealed that the interaction between types of vehicle and various variables were significant. For instance, nonresident truck drivers were more likely to violate all types of risky violations, which increased the estimated odds of crashes, compared with resident truck drivers. Recommendations based on the results are provided for policy makers to reduce high crash rate in the state.
Źródło:
Journal of Sustainable Development of Transport and Logistics; 2017, 2, 2; 35-46
2520-2979
Pojawia się w:
Journal of Sustainable Development of Transport and Logistics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A turning point in the development of phytoplankton in the Vistula Lagoon (Southern Baltic Sea) at the beginning of the 21st century
Autorzy:
Kownacka, J.
Calkiewicz, J.
Kornijow, R.
Powiązania:
https://bibliotekanauki.pl/articles/2079096.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
phytoplankton community
zooplankton
multiannual change
nutrient
biomass
Vistula Lagoon
Southern Baltic Sea
21st century
Opis:
Phytoplankton community structure was studied from 2002 to 2016 in the Vistula Lagoon (southern Baltic Sea) in the context of the 2010 shift in its population, as well as the reason for this shift and its environmental impact. This evident shift was indicated by Multidimensional Scaling at the Bray Curtis similarity level of 31%. Before 2010, the primary components of phytoplankton were Cyanobacteria (up to 98% of the biomass, October 2007) and Chlorophyta (40%, July 2002). After 2010, the contribution of Cyanobacteria considerably decreased, and the proportions of other phyla increased. The total phytoplankton biomass positively correlated with phosphorus, and Cyanobacteria biomass with silica. Evident changes were also observed in the seasonal dynamics of phytoplankton. Before 2010, the highest values of biomass occurred in autumn, and were related to high biomass of Cyanobacteria. Higher biomass has been recently reached in spring, during the dominance of Ochrophyta associated with Chlorophyta, Charophyta, and Cryptophyta. Generalised additive models showed a significant decreasing trend of the total phytoplankton biomass, Cyanobacteria, Chlorophyta, and flagellates, suggesting a decrease in eutrophication. This trend is concurrent with a considerable increase in the ratio of zooplankton to phytoplankton biomass since 2010. The increased ratio, however, did not result from elevated zooplankton biomass, but from the drop in phytoplankton biomass. Therefore, the most probable reason for the decrease in phytoplankton biomass was the simultaneous decrease in the concentration of all nutrients. The potential additional impact of filtration by a new alien bivalve Rangia cuneata G. B. Sowerby I, 1832 is also discussed.
Źródło:
Oceanologia; 2020, 62, 4PA; 538-555
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Urban area change visualization and analysis using high density spatial data from time series aerial images
Autorzy:
Altuntas, Cihan
Powiązania:
https://bibliotekanauki.pl/articles/106855.pdf
Data publikacji:
2019
Wydawca:
Politechnika Warszawska. Wydział Geodezji i Kartografii
Tematy:
photogrammetry
aerial image
image-based point cloud
digital elevation model
visualization of changes
urban area
fotogrametria
zdjęcie lotnicze
chmura punktów
cyfrowy model wysokościowy
wizualizacja zmian
przestrzeń miejska
Opis:
Urban changes occur as a result of new constructions or destructions of buildings, extensions, excavation works and earth fill arising from urbanization or disasters. The fast and efficient detection of urban changes enables us to update geo-databases and allows effective planning and disaster management. This study concerns the visualization and analysis of urban changes using multi-period point clouds from aerial images. The urban changes in the city centre of the Konya Metropolitan area within arbitrary periods between the years 1951, 1975, 1998 and 2010 were estimated after comparing the point clouds by using the iterative closest point (ICP) algorithm. The changes were detected with the point-to-surface distances between the point clouds. The degrees of the changes were expressed with the RMSEs of these point-to-surface distances. In addition, the change size and proportion during the historical periods were analysed. The proposed multi-period change visualization and analysis method ensures strict management against unauthorized building or excavation and more operative urban planning.
Źródło:
Reports on Geodesy and Geoinformatics; 2019, 107; 1-12
2391-8365
2391-8152
Pojawia się w:
Reports on Geodesy and Geoinformatics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigating the recent drought effects on underground water resources in the province of Kurdistan from a quantitative and qualitative point of view (Case study: Dehgolan and Ghorveh plains)
Autorzy:
Bashiri, E.
Bashiri, J.
Karimi, F.
Powiązania:
https://bibliotekanauki.pl/articles/11333.pdf
Data publikacji:
2013
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
drought effect
underground water
water resource
Kurdistan region
Dehgolan plain
Ghorveh plain
climate change
water level fluctuation
hydrology
deposit type
hydrochemistry
Opis:
The Ghorveh plain with an annual average rainfall of 350 millimeter and a cold and semi humid climate is located between the Dehgolan's watersheds and Chahardoli and 95 kilometers east of Sanandaj and northwest of Hamadan. From a geographic coordinates point of view it is situated between the longitudes of 47° 38' 52" to 48° 06' 03" eastern and latitudes of 35° 02' 22" to 35° 30' 54" northern . This plain leads to Mts. Darvazeh and Ebrahim Attar from south, it leads to hillside lands from the northern side , from Westside it reaches Mt. Bikheir and from the eastern part it is limited to the Dam Gaz heights. The area of the Ghorveh watershed is 1063/50 square kilometers while the area of the region under study is 197 square kilometers. Geologically speaking, it is located in the Sanadaj –Sirjan zone. The collision depth to the underground waters in the heights range bordering the plain is a maximum of 42 meters while the same rate about the river Talvar is at least zero and it is less than 5 meters in a wide range region of the eastern side of the plain. The direction of the underground water flow in the Ghorveh region is from the south west to north east. The Piezometrical water level changes compared to the western side plain has had a reduced height.The Dehgolan's plain with an annual average rainfall of 354 millimeters and a cold and semi humid climate is located in the eastern side of the city of Sanandaj between the longitudes of 47° 08' 00" to 48° 12' 00" eastern and latitudes of 35° 00' 00" to 36° 00'00" northern. This plain is limited to not very high ridge of Shanooreh from the eastern side and it leads to the Darband Kabood heights and Abdulrahman heights from south, while it leads to Mt. Sheida and Akhikamal and Salarabad from north and then it is limited to the Khatoon heights from the west part . The area of the watershed of Dehgolan is 2250 square kilometer and the area of the region under study is 644 square kilometers . Geologically and regionally speaking, it is part of the geological – structural zone of Sanandaj – Sirjan. The general slope of the region is towards east and north east. The main river of this plain is called Talvar. The alluvial aquifer of the Dehgolan's plain is of a free type and is on average 90meters thick where in some parts thickness swells to 90 meters.
Źródło:
International Letters of Natural Sciences; 2013, 03
2300-9675
Pojawia się w:
International Letters of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A comparison study between advance transfer technique and advance transfer mathematical model using bulk carrier ship: cross-track distance validation by percentage change and mann whitney u test
Autorzy:
Kamis, A. S.
Ahmad Fuad, A. S.
Powiązania:
https://bibliotekanauki.pl/articles/2211981.pdf
Data publikacji:
2022
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
bulk carriers
coss-track distance
ECDIS
wheel over point
advanced transfer technique
advance transfer mathematical model
wilcoxon-mann whitney u tes
IBM SPSS
Opis:
One of the methods of efficient course alteration is through the accurate identification of the WOP by ATT. ATT is widely used by mariners worldwide, and recently, the technique has been restructured and enhanced into ATMM. To prove the efficacy of ATMM over ATT, a few types of ships have been used to carry out the manoeuvring analysis. This study extends the analysis by using a bulk carrier ship. A ship simulator was used for a manoeuvring simulation study, which was carried out to verify the differences between these two methods. Throughout the manoeuvring simulation study, XTD data for each simulation was monitored and verified by XTL compliance, percentage variation, and the Wilcoxon-Mann Whitney U Test via IBM SPSS. It was found that the ATMM can produce a significantly improved WOP compared to ATT and is suitable to be used onboard a bulk carrier ship. This research's finding is expected to contribute as evidence to strengthen ATMM's efficiency so that it can be accepted as an ECDIS algorithm for ship navigation.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2022, 16, 3; 541--551
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Towards development of a prototype high-temperature latent heat storage unit as an element of a RES-based energy system (part 2)
Autorzy:
Karwacki, J.
Bogucka-Bykuć, K.
Włosiński, W.
Bykuć, S.
Powiązania:
https://bibliotekanauki.pl/articles/201730.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
latent heat storage
LHS
phase change material
PCM
metal alloy
middle melting point metal PCM
magazynowanie ciepła utajonego
materiał zmiennofazowy
stop metalu
środkowa temperatura topnienia metalu PCM
Opis:
This paper presents an experimental study performed with the general aim of defining procedures for calculation and optimization of shell-and-tube latent thermal energy storage unit with metals or metal alloys as PCMs. The experimental study is focused on receiving the exact information about heat transfer between heat transfer fluid (HTF) and phase change material (PCM) during energy accumulation process. Therefore, simple geometry of heat transfer area was selected. Two configurations of shell-and-tube thermal energy storage (TES) units were investigated. The paper also highlights the emerging trend (reflected in the literature) with respect to the investigation of metal PCM-based heat storage units in recent years and shortly presents unique properties and application features of this relatively new class of PCMs.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2016, 64, 2; 401-408
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of montmorillonite content on change the physicochemical properties of lubricating greases produced from vegetable base oil
Wpływ zawartości montmorylonitu na zmianę właściwości fizykochemicznych smarów plastycznych wytworzonych na bazie roślinnej
Autorzy:
Kozdrach, Rafał
Powiązania:
https://bibliotekanauki.pl/articles/1834404.pdf
Data publikacji:
2020
Wydawca:
Instytut Nafty i Gazu - Państwowy Instytut Badawczy
Tematy:
lubricating grease
modifying additive
stratified silicate
physicochemical properties
penetration
penetration after prolonged
kneading
dropping point
emission of oil
anti-corrosive properties by dynamic method
mechanical stability
oxidation
smar plastyczny
dodatek modyfikujący
krzemian warstwowy
właściwości fizykochemiczne
penetracja
penetracja po
przedłużonym ugniataniu
temperatura kroplenia
wydzielanie oleju
właściwości przeciwkorozyjne oznaczone metodą dynamiczną
stabilność mechaniczna
utlenialność
Opis:
W publikacji przedstawiono wyniki badań wpływu różnej ilości dodatku modyfikującego na właściwości fizykochemiczne wybranych kompozycji smarowych. Do modyfikacji smaru plastycznego wytworzonego na bazie roślinnej i zagęszczonego stearynianem litu zastosowano montmorylonit, przedstawiciela krzemianów warstwowych. Wykonano badania właściwości fizykochemicznych smaru plastycznego bazowego oraz smarów plastycznych zawierających dodatek modyfikujący, a otrzymane wyniki porównano. Wyznaczono penetrację, penetrację po przedłużonym ugniataniu, temperaturę kroplenia, wydzielanie oleju ze smaru, właściwości przeciwkorozyjne uzyskane metodą dynamiczną, stabilność mechaniczną – próba wałkowania oraz utlenialność na aparacie PetroOxy. Na podstawie analizy otrzymanych wyników badań fizykochemicznych stwierdzono, że zastosowany dodatek modyfikujący powoduje wzrost temperatury kroplenia, która decyduje o granicy stosowalności wytworzonych smarów plastycznych oraz wpływa na spadek wydzielania oleju ze smaru, który świadczy o skuteczności smarowania elementów trących badanymi kompozycjami smarowymi. Dodatek wpływa korzystnie na stabilność mechaniczną, zmniejsza stopień skorodowania łożysk kulkowych pracujących w obecności badanych smarów plastycznych, co z kolei korzystnie oddziałuje na stan maszyn i urządzeń, w których smary te są stosowane, oraz zwiększa stabilność oksydacyjną, gdy zawartość dodatku w smarze wynosi co najmniej 5%.
Źródło:
Nafta-Gaz; 2020, 76, 4; 270-278
0867-8871
Pojawia się w:
Nafta-Gaz
Dostawca treści:
Biblioteka Nauki
Artykuł
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