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Wyszukujesz frazę "pattern analysis" wg kryterium: Temat


Tytuł:
Don’t fight the tape! Technical Analysis Momentum and Contrarian Signals as Common Cognitive Biases
Autorzy:
Zielonka, Piotr
Białaszek, Wojciech
Biedrzycki, Paweł
Dzik, Bartłomiej
Powiązania:
https://bibliotekanauki.pl/articles/1933544.pdf
Data publikacji:
2020-02
Wydawca:
Akademia Leona Koźmińskiego w Warszawie
Tematy:
technical analysis
pattern recognition
cognitive biases
momentum
contrarian
Opis:
Purpose: Stock market participants use technical analysis to seek trends in stock price charts despite its doubtful efficiency. We tested whether technical analysis signals represent typical and common cognitive biases associated with the continuation or reversal of the trend. Methodology: We compared investors’ opinions about the predictive power of technical analysis signals grouped into five conditions: real technical analysis signals associated with trend continuation (real momentum signals) or trend reversal (real contrarian signals), fake momentum or fake contrarian signals, and fluctuation signals. Findings: Investors assigned larger predictive power to real and fake signals associated with trend continuation than to signals associated with trend reversal. Fake signals, which represented cognitive biases, elicited similar predictions about trend continuation or reversal to real technical analysis signals. Originality: Market players assess momentum signals to have greater predictive power than contrarian signals and neutral signals to have the least predictive power. These results are independent of whether technical analysis signals were well-known to investors or made up by experimenters. The hardwired propensity of our brains to detect patterns combined with the non-natural environment of the stock market creates the illusion of expertise that is not easy to dispel.
Źródło:
Central European Management Journal; 2020, 28(2); 98-110
2658-0845
2658-2430
Pojawia się w:
Central European Management Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental Tests of the Vector II Slab in Field Conditions, Slab and Strip Model
Autorzy:
Zając, Jakub
Drobiec, Łukasz
Jasiński, Radosław
Wieczorek, Mirosław
Kisiołek, Artur
Powiązania:
https://bibliotekanauki.pl/articles/1838083.pdf
Data publikacji:
2021
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
crack pattern
flexural analysis
interface
precast
slab
short-term load
pęknięcia
zginanie
prefabrykaty
płyty
obciążenie krótkotrwałe
Opis:
Vector II slab was tested on a natural scale (a slab with a dimension of 6.30 × 6.30 m) and a strip 6.30 m long and 1.20 m wide. The Vector II slab is built by precast panel 60 cm wide, 4 cm thick and 14-20 cm thick concrete overtopping on the construction site. The main purpose of the slab tests on a natural scale was to observe the "faulting" effect and temporary deflections. During the tests, the displacements in the area of the panel joints in the middle of the slab span were recorded. The maximum difference in displacement between adjacent panels of the slab model was 0.16 mm, and the vertical displacement was 1.9 mm. The strip model had no cracks that could indicate a interface cracks between the precast element and the concrete overlay. After completion of the field tests, the load was left on the slab model to verify long-term effects.
Źródło:
Civil and Environmental Engineering Reports; 2021, 31, 1; 54-69
2080-5187
2450-8594
Pojawia się w:
Civil and Environmental Engineering Reports
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental Tests of the Vector II Slab in Field Conditions, Slab and Strip Model
Autorzy:
Zając, Jakub
Drobiec, Łukasz
Jasiński, Radosław
Wieczorek, Mirosław
Kisiołek, Artur
Powiązania:
https://bibliotekanauki.pl/articles/1838085.pdf
Data publikacji:
2021
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
crack pattern
flexural analysis
interface
precast
slab
short-term load
pęknięcia
zginanie
prefabrykaty
płyty
obciążenie krótkotrwałe
Opis:
Vector II slab was tested on a natural scale (a slab with a dimension of 6.30 × 6.30 m) and a strip 6.30 m long and 1.20 m wide. The Vector II slab is built by precast panel 60 cm wide, 4 cm thick and 14-20 cm thick concrete overtopping on the construction site. The main purpose of the slab tests on a natural scale was to observe the "faulting" effect and temporary deflections. During the tests, the displacements in the area of the panel joints in the middle of the slab span were recorded. The maximum difference in displacement between adjacent panels of the slab model was 0.16 mm, and the vertical displacement was 1.9 mm. The strip model had no cracks that could indicate a interface cracks between the precast element and the concrete overlay. After completion of the field tests, the load was left on the slab model to verify long-term effects.
Źródło:
Civil and Environmental Engineering Reports; 2021, 31, 1; 54-69
2080-5187
2450-8594
Pojawia się w:
Civil and Environmental Engineering Reports
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Intelligent pattern recognition of SLM machine energy data
Autorzy:
Uhlmann, E.
Pastl Pontes, R.
Laghmouchi, A.
Hohwieler, E.
Feitscher, R.
Powiązania:
https://bibliotekanauki.pl/articles/99469.pdf
Data publikacji:
2017
Wydawca:
Wrocławska Rada Federacji Stowarzyszeń Naukowo-Technicznych
Tematy:
pattern recognition
data analysis
additive manufacturing
energy data
Opis:
Selective Laser Melting (SLM) is an additive manufacturing process, in which the research has been increasing over the past few years to meet customer-specific requirements. Different parameters from the process and the machine components have been monitored in order to obtain vital information such as productivity of the machine and quality of the manufactured workpiece. The monitoring of parameters related to energy is also realized, but the utilisation of such data is usually performed for determining basic information, for instance, from energy consumption. By applying machine learning algorithms on these data, it is possible to identify not only the steps of the manufacturing process, but also its behaviour patterns. Along with these algorithms, evidences regarding the conditions of components and anomalies can be detected in the acquired data. The results can be used to point out the process errors and component faults and can be adopted to analyse the energy efficiency of the SLM process by comparing energy consumption of one single layer during the manufacturing of different components. Moreover, the state of the manufacturing process and the machine can be determined automatically and applied to predict failures in order to launch appropriate counter measures.
Źródło:
Journal of Machine Engineering; 2017, 17, 2; 65-76
1895-7595
2391-8071
Pojawia się w:
Journal of Machine Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An experimental study of the vibrational characteristics of a diamond circular blade using electronic speckle-pattern interferometry and fem
Autorzy:
Tkach, Mykhaylo
Halynkin, Yurii
Proskurin, Arkadii
Zhuk, Irina
Kluchnyk, Volodymyr
Bobylev, Igor
Powiązania:
https://bibliotekanauki.pl/articles/1837945.pdf
Data publikacji:
2021
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
interferometry
speckle pattern
correlation fringes
vibration analysis
Opis:
The compact installation and technology for determining vibration characteristics by the ESPI method has been created. The experimental determination of the dynamic characteristics of a diamond circular blade with a diameter of 203.4 mm and a thickness of 1.19 mm using real-time electronic speckle interferometry is presented. 15 mode shapes of vibration were detected in the range from 100 to 5000 Hz. The program calculation of the natural frequencies and mode shapes is carried out for three values of the clamping inner diameter (42 mm, 44 mm, 46 mm). The options for calculating a disk with a rim and without a rim are considered. It is shown that the minimum mean squared error of the calculation is achieved for the values of the diameter of the disk 46 mm, 42 mm and 44 mm for the number of nodal circles 0, 1 and 2, respectively. To verify the accuracy of the interferometer, experimental, computational and analytical studies of console steel rod 200 x 22.25 x 3.78 mm in size were carried out.
Źródło:
Acta Mechanica et Automatica; 2021, 15, 1; 16-23
1898-4088
2300-5319
Pojawia się w:
Acta Mechanica et Automatica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Picture Languages in Automatic Radiological Palm Interpretation
Autorzy:
Tadeusiewicz, R.
Ogiela, M. R.
Powiązania:
https://bibliotekanauki.pl/articles/908539.pdf
Data publikacji:
2005
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
komputerowe wspomaganie diagnozy
diagnostyka choroby
choroba dłoni
syntaktyczne rozpoznawanie obrazu
rozumienie obrazu
medyczna analiza obrazu
syntactic pattern recognition
image understanding
medical image analysis
computer-aided diagnosis
palm disease diagnostics
Opis:
The paper presents a new technique for cognitive analysis and recognition of pathological wrist bone lesions. This method uses AI techniques and mathematical linguistics allowing us to automatically evaluate the structure of the said bones, based on palm radiological images. Possibilities of computer interpretation of selected images, based on the methodology of automatic medical image understanding, as introduced by the authors, were created owing to the introduction of an original relational description of individual palm bones. This description was built with the use of graph linguistic formalisms already applied in artificial intelligence. The research described in this paper demonstrates that for the needs of palm bone diagnostics, specialist linguistic tools such as expansive graph grammars and EDT-label graphs are particularly well suited. Defining a graph image language adjusted to the specific features of the scientific problem described here permitted a semantic description of correct palm bone structures. It also enabled the interpretation of images showing some in-born lesions, such as additional bones or acquired lesions such as their incorrect junctions resulting from injuries and synostoses.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2005, 15, 2; 305-312
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Changes in gait pattern in patients with scoliosis
Zmiany stereotypu chodu u pacjentów z bocznym skrzywieniem kręgosłupa
Autorzy:
Syczewska, Małgorzata
Łukaszewska, Anna
Górak, Beata
Graff, Krzysztof
Powiązania:
https://bibliotekanauki.pl/articles/1937268.pdf
Data publikacji:
2006
Wydawca:
Akademia Wychowania Fizycznego im. Bronisława Czecha w Krakowie
Tematy:
Scoliosis
gait analysis
gait pattern
skrzywienie kręgosłupa
analiza chodu
stereotyp chodu
Opis:
Introduction. Scoliosis is the most common orthopaedic disorder among children and adolescents thus constituting a serious social problem. 3D deformation of the spine changes the mechanics of the whole body. The aim of this work was to assesschanges in gait pattern in patients with scoliosis.Material and methods. Patients: 25 girls aged 12-16 years with idiopathic scoliosis greater than 20 degrees, not treated earlier. Method: objective gait analysis using the system VICON 460 synchronized with dynamic electromyography system and dynamographic platform. Measured parameters: spatio-temporal, kinematic, surface EMG of selected limb and trunk muscles. Calculations were performed with Polygon software.Results. Decreased pelvic tilt was found in 90 % of patients, together with an increased pelvic tilt range. In 2/3 of patients, the pelvis was obliqued in the frontal plane, and in the majority, the pelvis was rotated in the transverse plane with respect to the line of progression. The orientation of the hip joints in the frontal and transverse planes was incorrect in half of the patients, and the knees were slightly flexed at initial contact. In some patients, there was a diminished range of motion of the hip joints in the saggital plane, accompanied by an increased internal pelvic rotation at the initial contact. In all patients, the feet were dorsiflexed in the ankle joints in the swing phase, and in the transverse plane, there was an internal rotation of the feet with respect to the shank. In all patients, there was also an abnormal, asymmetrical activity of the trunk muscles, and of the greatest gluteal muscles.Conclusions. Scoliosis changes body mechanics and the orientation of the pelvis at least in one plane (in most cases – in all three planes). Compensatory mechanisms occur that may lead to further pathologies. The increased dorsiflexion of the feet in the swing phase was a surprising finding. As the maximum flexion of the knees in this phase is correct, the increased dorsiflexion could not have served as a compensatory mechanism helping in foot clearance.
Wstęp. Boczne skrzywienie kręgosłupa to najczęściej występujące wśród dzieci i młodzieŜy schorzenie ortopedyczne, stanowiące poważny problem społeczny. Wielopłaszczyznowa deformacja kręgosłupa zaburza mechanikę ciała. Celem pracy była ocena zmian stereotypu chodu u pacjentów z bocznym skrzywieniem kręgosłupa. Materiał i metody. 25 dziewcząt w wieku 12-16 lat z bocznym idiopatycznym skrzywieniem kręgosłupa powyżej 20 stopni, nie leczonych wcześniej. Metody: analiza chodu za pomocą systemu VICON 460 z systemem do elektromiografii dynamicznej oraz z platformą dynamograficzną. Mierzono parametry czasowo-przestrzenne, kinematyczne oraz EMG wybranych mięśni kończyn dolnych i tułowia. Obliczenia wykonano za pomocą programu Polygon. Wyniki. U 90% pacjentek stwierdzono zmniejszone przodopochylenie miednicy, zwiększony zakres ruchu miednicy w pł. strzałkowej. U 2/3 miednica była ustawiona skośnie w pł. czołowej, a u większości takŜe skręcona względem linii kierunkowej chodu w pł. poprzecznej. U połowy ustawienie stawów biodrowych w pł. czołowej i poprzecznej było nieprawidłowe, a kontakt z podłożem odbywał się przy lekko zgiętych kolanach. U części pacjentek stwierdzono zmniejszenie zakresu ruchu w stawach biodrowych w pł. strzałkowej, ze zwiększoną rotacją wewnętrzną miednicy w chwili kontaktu z podłożem. U wszystkich stwierdzono zgięcie grzbietowe stóp w fazie wymachu oraz wewnętrzną rotację stóp względem goleni, a takŜe nieprawidłowy, asymetryczny zapis EMG mm. pośladkowych wielkich oraz wzdłuż kręgosłupa. Wnioski. Boczne skrzywienie kręgosłupa zaburza mechanikę ciała, zmienia orientację miednicy podczas chodu przynajmniej w jednej płaszczyźnie, w większości przypadków we wszystkich trzech. Pojawiają się mechanizmy kompensacyjne, które mogą stać się źródłem kolejnych nieprawidłowości. Zaskakującym zjawiskiem jest zgięcie grzbietowe stóp w fazie wymachu. PoniewaŜ u wszystkich pacjentek zgięcie kolan w fazie wymachu jest prawidłowe nie może to być mechanizm ułatwiający przenoszenie kkd nad podłoŜem.
Źródło:
Medical Rehabilitation; 2006, 10(4); 18-24
1427-9622
1896-3250
Pojawia się w:
Medical Rehabilitation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Estimation of significance of AlkB and AlkA proteins in DNA repair in Escherichia coli model
Autorzy:
Sokołowska, B.
Maciejewska, A. M.
Jóźwik, A.
Kuśmierek, J. T.
Powiązania:
https://bibliotekanauki.pl/articles/333316.pdf
Data publikacji:
2011
Wydawca:
Uniwersytet Śląski. Wydział Informatyki i Nauki o Materiałach. Instytut Informatyki. Zakład Systemów Komputerowych
Tematy:
rozpoznawanie obrazów
klasyfikator najbliższych sąsiadów
analiza cech pracy odbiornika
naprawa DNA
adaptacyjna odpowiedź
powstawanie mutacji
bakterie e.coli
pattern recognition
fuzzy k-NN classifier
ROC analysis
DNA repair
adaptive response
mutagenesis
AlkB dioxygenase
AlkA glycosylase
E.coli
Opis:
The paper concerns estimation of significance of differences of mutagenesis level between the wild-type strain (wt) and its derivatives which differ in DNA repair ability, namely alkA and alkB strain, devoided AlkA glycosylase and AlkB dioxygenase activity, respectively. The strains were analyzed for their ability to repair 1,N6-ethenoadenine (εA) - chloroacetaldehyde adduct to DNA. The analysis was done using classical statistical and pattern recognition methods. The obtained results confirmed that AlkB dioxygenase plays the most important role in εA repair in E. coli in the experimental modeling.
Źródło:
Journal of Medical Informatics & Technologies; 2011, 17; 321-326
1642-6037
Pojawia się w:
Journal of Medical Informatics & Technologies
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fossil population structure and mortality analysis of the cave bears from Ursilor Cave, north-western Romania
Autorzy:
Robu, M.
Powiązania:
https://bibliotekanauki.pl/articles/20701.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
fossil
population structure
mortality analysis
cave bear
Mammalia
Ursus spelaeus
cave taphonomy
death pattern
sex ratio
Ursilor Cave
Romania
Carpathians Mountains
Opis:
Research in cave bear palaeobiology focusing on population structure and mortality analysis may improve our understanding regarding the ecology of this species which vanished at the end of Marine Isotope Stage (MIS) 3, prior to Last Glacial Maximum (LGM), if assessed populations are large enough. Such population is available in Urşilor Cave, from north-western Romania, known as one of the most rich and complex European MIS3 cave bear sites. From the palaeontological excavation, situated at the lower level of the cave (= Scientific Reserve), more than 210 cave bear isolated lower molars, 160 mandibles and almost 180 canines were extracted and analyzed. The results obtained on the wear stages of the studied molars and mandibles indicated an “L”-shaped curve and suggest a non-attritional death pattern and a bone assemblage juvenile dominated. Moreover, the sex-ratio of upper and lower canines indicates a net dominance of females (5.4 females: 1 male). Although a “catastrophic” death pattern was obtained for cave bears, the animals seem to have died diachronically (non-simultaneously), over a time span of more than 6000 years. The triangular graph of age distribution is not appropriate for death assemblages from traps such as karst caves, where taphonomic processes like predation or scavenging would have played a less important role.
Źródło:
Acta Palaeontologica Polonica; 2016, 61, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Determination of contact pattern for double enveloping worm gear
Autorzy:
Połowniak, Piotr
Sobolak, Mariusz
Marciniec, Adam
Powiązania:
https://bibliotekanauki.pl/articles/1831346.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
globoid worm gear
contact pattern
CAD environment
tooth contact analysis
meshing simulation
globoidalna przekładnia ślimakowa
ślad styku
środowisko CAD
analiza styku zębów
symulacja zazębienia
Opis:
The paper presents the method of determining geometric contact pattern by using the direct computer-aided design (CAD) method for ideal globoid worm gear in which mounting deviations are considered. The tooth contact analysis was performed for all cycle of worm rotation. Based on the results of temporary contact pattern, graphical characteristics of the contact area size depending on worm position were made. A complete analysis of the correctness of gear meshing can be obtained based on presented method. If the worm or worm wheel is incorrectly designed in terms of the geometry, the meshing simulation of CAD models can indicate the collision. Geometric contact pattern analyses were made at two pressure angles of ideal gear. The analysis of the influence of mounting deviations was done against one selected pressure angle and one gear position.
Źródło:
Advances in Manufacturing Science and Technology; 2020, 44, 4; 145-154
0137-4478
Pojawia się w:
Advances in Manufacturing Science and Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Critical exponent analysis applied to surface EMG signals for multifunction myoelectric control
Autorzy:
Phinyomark, A.
Phothisonothai, M.
Phukpattaranont, P.
Limsakul, C.
Powiązania:
https://bibliotekanauki.pl/articles/220544.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
biomedical signal processing
electromyography signal
feature extraction
fractal analysis
human machine interface
pattern classification
Opis:
Based on recent advances in non-linear analysis, the surface electromyography (sEMG) signal has been studied from the viewpoints of self-affinity and complexity. In this study, we examine usage of critical exponent analysis (CE) method, a fractal dimension (FD) estimator, to study properties of the sEMG signal and to deploy these properties to characterize different movements for gesture recognition. SEMG signals were recorded from thirty subjects with seven hand movements and eight muscle channels. Mean values and coefficient of variations of the CE from all experiments show that there are larger variations between hand movement types but there is small variation within the same type. It also shows that the CE feature related to the self-affine property for the sEMG signal extracted from different activities is in the range of 1.855∼2.754. These results have also been evaluated by analysis-of-variance (p-value). Results show that the CE feature is more suitable to use as a learning parameter for a classifier compared with other representative features including root mean square, median frequency and Higuchi's method. Most p-values of the CE feature were less than 0.0001. Thus the FD that is computed by the CE method can be applied to be used as a feature for a wide variety of sEMG applications.
Źródło:
Metrology and Measurement Systems; 2011, 18, 4; 645-658
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Selected Methods of the Pattern Electroretinogram Signal Analysis
Wybrane metody analizy sygnału Elektroretinogramu wywołanego wzorcem
Autorzy:
Penkala, K.
Rogala, T.
Brykalski, A.
Powiązania:
https://bibliotekanauki.pl/articles/156978.pdf
Data publikacji:
2007
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
analiza sygnałów
elektroretinogram wywołany wzorcem
PERG
analiza statystyczna
ciągła transformata falkowa
sztuczne sieci neuronowe
analiza składowych niezależnych
signal analysis
pattern electroretinogram
statistical analysis
continuous wavelet transform (CWT)
artificial neural networks
independent component analysis
Opis:
In the paper a short review of methods applied for pattern electroretinogram signal analysis is presented. Various possible alternatives for classical method used in medical practice are described. The capabilities and disadvantages of each method as well as relevant results are briefly presented and/or references are cited. The described algorithms are: statistical regression analysis, continuous wavelet transform, discrete wavelet transform, artificial neural networks, principal components analysis and independent component analysis. The aim of the paper is to give a short review of previously taken activity in the field of pattern electroretinogram analysis particularly for diagnostic purposes, and present a guide for possible approaches to be applied for other bioelectrical signals.
W artykule przedstawiono przegląd metod zastosowanych do analizy sygnału elektroretinogramu wywołanego wzorcem. Zaprezentowano szereg możliwych technik alternatywnych w stosunku do procedur używanych w praktyce klinicznej. Przedyskutowano zalety i ograniczenia każdego z algorytmów, przedstawiając pokrótce wyniki doświadczeń lub cytując odpowiednie pozycje literatury. Opisane algorytmy to: statystyczna analiza regresji, ciągła i dyskretna transformata falkowa, sztuczne sieci neuronowe, analiza składowych głównych (PCA) oraz analiza składowych niezależnych (ICA). Celem niniejszego artykuły jest usystematyzowanie wcześniejszych działań autorów w dziedzinie analizy elektroretinogramu wywołanego wzorcem, w szczególności dla potrzeb diagnostyki, oraz zaproponowanie metodologii badań sygnałów bioelektrycznych o podobnym charakterze.
Źródło:
Pomiary Automatyka Kontrola; 2007, R. 53, nr 6, 6; 22-25
0032-4140
Pojawia się w:
Pomiary Automatyka Kontrola
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of infill and density pattern on the mechanical behaviour of ABS parts manufactured by FDM using Taguchi and ANOVA approach
Autorzy:
Othmani, M.
Zarbane, K.
Chouaf, A.
Powiązania:
https://bibliotekanauki.pl/articles/2175753.pdf
Data publikacji:
2021
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
fused deposition modelling
infill pattern
infill density
finite element analysis
Taguchi
modelowanie metodą osadzania topionego
wzór wypełnienia
gęstość wypełnienia
analiza elementów skończonych
Opis:
Purpose: The present work aims to investigate the effect of many infill patterns (rectilinear, line, grid, triangles, cubic, concentric, honeycomb, 3D honeycomb) and the infill density on the mechanical tensile strength of an Acrylonitrile Butadiene Styrene (ABS) test specimen manufactured numerically by FDM. Design/methodology/approach: Computer-Aided Design (CAD) software has been used to model the geometry and the mesostructure of the test specimens in a fully automatic manner from a G-code file by using a script. Then, a Numerical Design of Experiments (NDoE) has been carried out by using Taguchi method and the Analysis of Variance (ANOVA). The tensile behaviour of these numerical test specimens has been studied by the Finite Element Analysis (FEA). Findings: The FEA results showed that a maximal Ultimate Tensile Strength (UTS) was reached by using the ‘concentric’ infill pattern combined with an infill density of 30%. The results also show that the infill pattern and the infill density are significant factors. Research limitations/implications: The low infill densities of 20% and 30% that have already been used in many previous studies, we have also applied it in order to reduce the time of the simulations. Indeed, with high infill density, the simulations take a very excessive time. In an ongoing study, we predicted higher percentages. Practical implications: This study provided an important modelling tool for the design and manufacture of functional parts and helps the FDM practitioners and engineers to manufacture strong and lightweight FDM parts by choosing the optimal process parameters. Originality/value: This study elucidated the effect of various infill patterns on the tensile properties of the test specimens and applied for the first time a NDoE using numerical test specimens created by the mesostructured approach, which considerably minimized the cost of the experiments while obtaining an error of 6.8% between the numerical and the experimental values of the UTS.
Źródło:
Archives of Materials Science and Engineering; 2021, 111, 2; 66--77
1897-2764
Pojawia się w:
Archives of Materials Science and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
IMAGE PATTERN ANALYSIS WITH IMAGE POTENTIAL TRANSFORM
Autorzy:
Oleg, Butusov
Dikusar, Vasily
Powiązania:
https://bibliotekanauki.pl/articles/452838.pdf
Data publikacji:
2018
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Katedra Ekonometrii i Statystyki
Tematy:
binary image transform
distance and potential transform
statistical indices
geometric signatures
pattern analysis
pattern recognition
Opis:
Pattern analysis with image transform based on potential calculation was considered. Initial gray-scale image is sliced into equidistant levels and resulting binary image was prepared by joining of some levels to one binary image. Binary image was transformed under assumption that white pixels in it may be considered as electric charges or spins. Using this assumption Ising model and Coulomb model interaction between white pixels was used for image potential transform. The transform was calculated using moving window. The resulting gray-scale image was again transformed to binary image using the thresholding on 0.5 level. Further binary images were analyzed using statistical indices (average, standard deviation, skewness, kurtosis) and geometric signatures: area, eccentricity, Euler number, orientation and perimeter. It was found that the most suitable geometric signature for pattern configuration analysis of Ising potential transform (IPT) and Coulomb potential transform (CPT) is area value. Similarly the most suitable statistics is distance statistics between white pixels.
Źródło:
Metody Ilościowe w Badaniach Ekonomicznych; 2018, 19, 1; 12-27
2082-792X
Pojawia się w:
Metody Ilościowe w Badaniach Ekonomicznych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
L1-optimal Statistical Discrimination Procedures and their Asymptotic Properties
Autorzy:
Niemiro, Wojciech
Powiązania:
https://bibliotekanauki.pl/articles/747673.pdf
Data publikacji:
1989
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
Classification and discrimination, cluster analysis
Asymptotic distribution theory
Pattern recognition, speech recognition
Opis:
W pracy rozpatruje się procedury statystyczne, które można traktować jako procedury estymacji rozwiązania problemu minimalizacji kiedy łączny rozkład prawdopodobieństwa zmiennych losowych jest nieznany i może być oszacowany na podstawie próby losowej. Procedury takiego typu pojawiają się w teorii dyskryminacji statystycznej i odsiewania. Przedmiotem pracy jest badanie asymptotycznych własności takich procedur.
We consider the generalized Z^-norm optimization problem assuming that the joint probability distri-bution of random variables is unknown. The solution to the problem has, therefore, to be estimated from a sample. We examine a natural estimator and show its strong consistency and asymptotic normality under quite general assumptions. Certain discrimination and screening problems, formalized in decision- theoretical manner, can be solved using Z^-norm minimization procedures. We derive asymptotic expansions of risk corresponding to estimated solu-tions.
Źródło:
Mathematica Applicanda; 1989, 17, 31
1730-2668
2299-4009
Pojawia się w:
Mathematica Applicanda
Dostawca treści:
Biblioteka Nauki
Artykuł

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