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Wyniki wyszukiwania dla: STATISTIC
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A Consolidation Curve Reproduction Based on Sigmoid Model: Evaluation and Statistical Assessment
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The statistical impact of experimental result scatter of asphalt mixtures on their numerical modelling
PublikacjaThe paper presents selected test results of asphalt mixture conducted in low temperatures. The obtained parameters are highly diverse. It concerns ultimate breaking loads, stiffness parameters related to Young's modulus but also the fracture course. Statistical analysis upon the results makes it possible to relevantly estimate the material-defining parameter values. Such a random approach leads to the mean values of breaking and...
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Examining Statistical Methods in Forecasting Financial Energy of Households in Poland and Taiwan
PublikacjaThis paper examines the usefulness of statistical methods in forecasting the financial energy of households. The study’s objective is to create the innovative ratios that combine both financial and demographic information of households and implement them in the forecasting models. To conduct this objective, six forecasting models are developed using three different methods—discriminant analysis, logit analysis, and decision trees...
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A Consolidation Curve Reproduction Based on Sigmoid Model: Evaluation and Statistical Assessment
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A statistical approach to the identification of diploid cellular automata based on incomplete observations
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Music Information Retrieval – Soft Computing versus Statistics . Wyszukiwanie informacji muzycznej - algorytmy uczące versus metody statystyczne
PublikacjaMusic Information Retrieval (MIR) is an interdisciplinary research area that covers automated extraction of information from audio signals, music databases and services enabling the indexed information searching. In the early stages the primary focus of MIR was on music information through Query-by-Humming (QBH) applications, i.e. on identifying a piece of music by singing (singing/whistling), while more advanced implementations...
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Analysis of Modal Parameters Using a Statistical Approach for Condition Monitoring of the Wind Turbine Blade
PublikacjaThe primary objective of the presented paper is the numerical and experimental investigation related to developing a useful diagnostic method, which can be used for determining the site and size of damage in laminated shells of wind turbine blades. The described detection technique is based on the analysis of low frequencies bending vibrations mode shapes of rotor blades. The authors used the commonly applied statistics methods...
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Trace of Flicker Sources by Using Non-Parametric Statistical Analysis of Voltage Changes
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Statistical data of hull main parameters useful for preliminary design of SWATH ships
PublikacjaW artykule przedstawiono rezultaty badań dotyczących statystycznych relacji głównych parametrów projektowych kadłuba statków typu SWATH, wykonanych w oparciu o zebrane w literaturze przedmiotu dane o ponad osiemdziesięciu statkach. Zależności statystyczne przedstawiono w postaci histogramów: długości statku L, histogramów wartości stosunków długości do szerokości L/B, długości do wysokości bocznej L/H, długości pływaków do ich...
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Ryzyko statystyczne a ryzyko rzeczywistego pacjenta = Statistical risk and risk of the real patient
PublikacjaDzięki wieloletnim obserwacjom populacji ludzkiej udało się zidentyfikować czynniki ryzyka choroby wieńcowej. Najważniejsze z nich to: wiek, płeć, obciążenie genetyczne, palenie papierosów, stężenie cholesterolu we krwi, ciśnienie tętnicze, brak aktywności fizycznej, nadwaga, obecność cukrzycy. Obserwacje prospektywne populacji dostarczyły danych do opracowania modeli, które określają relacje między wartościami czynników ryzyka...
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Verification of Economic and Agricultural Indicators With the Use of Statistical Methods on the Example of Individual Farms
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Influence of statistical errors on damage detection based on structuralflexibility and mode shape curvature
PublikacjaDamage detection procedures based on measured natural frequencies and building structure mode shapes are discussed in this paper. Modal curvature and structural flexibility approaches are tested. Attention is paid to the modal identification errors that influence damage detection. This problem is studied using a computer simulation of a simple supported beam. For practical cases, the peak picking methodand its statistical errors...
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Statistical evaluation of the changes in cellulose properties caused by the stepwise solvent exchange and esterification
PublikacjaThe objective of the research was to empirically confirm the changes in cellulose reactivity caused by the pre-treatment with solvents of different polarity. Therefore, 5 solvents varying in their polar component of surface tension from 0 to 4.6 mN/m were chosen. Their impact on the biopolymer properties was carefully analysed concerning chemical structure, crystallinity and surface characteristics. It was revealed that the length...
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Measurements of Two-phase Flows in Pipelines Using Radioisotopes and Statistical Signal Processing
PublikacjaThis paper presents an application of radiotracers and gamma absorption method in two-phase flow measurements in pipelines. Two different methods were implemented to analysis of acquired signals. Investigated methods are based on the cross-correlation function and the phase of the cross-spectral density distribution. The examples presented in the article illustrate the application of the radioisotopes to evaluation of liquid-gas...
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Statistical evaluation of physical and index properties of Vistula Marshlands deltaic soft soils
PublikacjaThis paper provides statistical evaluation of physical and index parameters of the Vistula Marshlands deltaic soft soils using three datasets. Soft soils from the Vistula Marshlands are grouped into the four categories: (1) silty/sandy loams, (2) organic clays, (3) organic silts and (4) peats. Variability of basic and derivative physical properties as well as Atterberg's limits and plasticity index is studied. It is found that...
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Statistical description and numerical calculations of cylindrical vertical tanks with initial geometric imperfections
PublikacjaDokonano identyfikacji rzeczywistych wstępnych imperfekcji geometrycznych stalowych pionowych zbiorników walcowych. Imperfekcje przedstawiono jako pole losowe opisane za pomocą odpowiednio dobranej funkcji korelacyjnej, wartości oczekiwanej oraz obwiedni pola. Wykorzystując własne programy numeryczne przeprowadzono generację zbioru odchyłek geometrycznych zbiornika. Porównano estymatory wygenerowanego pola losowego z parametrami...
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Study of Statistical Text Representation Methods for Performance Improvement of a Hierarchical Attention Network
PublikacjaTo effectively process textual data, many approaches have been proposed to create text representations. The transformation of a text into a form of numbers that can be computed using computers is crucial for further applications in downstream tasks such as document classification, document summarization, and so forth. In our work, we study the quality of text representations using statistical methods and compare them to approaches...
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Fast multi-criterial statistical analysis and design optimization of compact microwave couplers
Publikacja—A rapid statistical analysis and yield estimation of compact microwave couplers involving multiple performance parameters has been presented. The analysis is realized using a fast surrogate model representing appropriate characteristic points of the coupler response. Because of less nonlinear dependence of the characteristic points on the structure geometry (compared to the original response, i.e., S-parameters vs. frequency),...
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Statistical evaluation of the effectiveness of different extraction techniques for determining robenidyne levels in poultry feed.
PublikacjaPoprzez zastosowanie testu Kruskala-Wallisa i chemometrycznej techniki analizy podobieństwa porównano efektywność sześciu różnych technik ekstrakcji (wytrząsanie, ekstrakcja w aparacie Soxhleta, w aparacie Soxteca, wspomaganej ultradźwiękami, wspomaganej promieniowaniem mikrofalowym oraz przyspieszonej ekstrakcji rozpuszczalnikiem) na podstawie wyników odzysku robenidyny z próbek paszy dla ptaków. W zależności od zastosowanej techniki...
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Optimization of briquetting technology of fine-grained metallurgical materials based on statistical models of compressibility
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Drawing conclusions about reliability of power systems from small number of statistical data
PublikacjaW artykule podjęto próbę udzielenia odpowiedzi na pytanie, czy możliwe jest wyciągnięcie przydatnych w praktyce wniosków o niezawodności elementów technicznych, wchodzących w skład systemów energetycznych, mając do dyspozycji nieliczne dane statystyczne. W opinii autora jest to możliwe. Wskazano dwie drogi postępowania. Pierwsza opiera się na wykorzystaniu metod statystycznych. Druga wykorzystuje elementy teorii zbiorów rozmytych.
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Surface water quality assessment by the use of combination of multivariate statistical classification and expert information
PublikacjaThe present study deals with the assessment of surface water quality from an industrial-urban region located in northern Poland near to the city of Gdansk. Concentrations of thirteen chemicals includingtotal polycyclic aromatic hydrocarbons (PAHs), halogenated volatile organic compounds (HVOCs) and major ions in the samples collected at five sampling points during six campaigns were used as variablesthroughout the study. The originality...
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Statistical-based approach in potential diagnostic application of urinary nucleosides in urogenital tract cancer
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Rapid Yield Estimation and Optimization of Microwave Structures Exploiting Feature-Based Statistical Analysis
PublikacjaIn this paper, we propose a simple, yet reliable methodology to expediteyield estimation and optimization of microwave structures. In our approach,the analysis of the entire response of the structure at hand (e.g., $S$-parameters asa function of frequency) is replaced by response surface modeling of suitablyselected feature points. On the one hand, this is sufficient to determinewhether a design satisfies given performance specifications....
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Multivariate statistical comparison of analytical procedures for benzene and phenol determination with respect to their environmental impact
PublikacjaThe studydescribesthepossibilityofapplicationofself-organizingmapstechniquetoassessthe greenness ofanalyticalmethodologies.Themetrologicaland “environmentalimpact” parametersof proceduresforbenzeneandphenoldeterminationinwatersamplesweresetsofinputdatafor chemometric analysis.Totally47objectsand8variablesformedthedatausedforanalysis.Themajor factors responsiblefornon-greencharacterofthemethodologyaretheamountoforganicsolventand amount...
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Statistical Method for Analysis of Interactions Between Chosen Protein and Chondroitin Sulfate in an Aqueous Environment
PublikacjaWe present the statistical method to study the interaction between a chosen protein and another molecule (e.g., both being components of lubricin found in synovial fluid) in a water environment. The research is performed on the example of univariate time series of chosen features of the dynamics of mucin, which interact with chondroitin sulfate (4 and 6) in four different saline solutions. Our statistical approach is based on recurrence...
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SCRAMBLE’N’GAMBLE: a tool for fast and facile generation of random data for statistical evaluation of QSAR models
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A new method of wind farm active power curve estimation based on statistical approach
PublikacjaThe purpose of this paper is to solve the wind farm active power estimation problem, introducing the method which is based on a statistical approach and robust fitting. The proposed algorithm uses a statistical approach and compared to existing ones- includes a wind direction as well as the influence of turbine start-up procedure on the estimation. The results show that additional estimation inputs i.e. the wind direction and the...
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APPLICATION OF STATISTICAL FEATURES AND MULTILAYER NEURAL NETWORK TO AUTOMATIC DIAGNOSIS OF ARRHYTHMIA BY ECG SIGNALS
PublikacjaAbnormal electrical activity of heart can produce a cardiac arrhythmia. The electrocardiogram (ECG) is a non-invasive technique which is used as a diagnostic tool for cardiac diseases. Non-stationarity and irregu- larity of heartbeat signal imposes many difficulties to clinicians (e.g., in the case of myocardial infarction arrhythmia). Fortunately, signal processing algorithms can expose hidden information within ECG signal contaminated...
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Statistical analysis and robust design of circularly polarized antennas using sequential approximate optimization
PublikacjaIn the paper, reliable yield estimation and tolerance-aware design optimization of circular polarization (CP) antennas is discussed. We exploit auxiliary kriging interpolation models established in the vicinity of the nominal design in order to speed up the process of statistical analysis of the antenna structure at hand. Sequential approximate optimization is then applied to carry out robust design of the antenna, here, oriented...
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Furan Fragmentation in the Gas Phase: New Insights from Statistical and Molecular Dynamics Calculations
PublikacjaWe present a complete exploration of the different fragmentation mechanisms of furan (C4H4O) operating at low and high energies. Three different theoretical approaches are combined to determine the structure of all possible reaction intermediates, many of them not described in previous studies, and a large number of pathways involving three types of fundamental elementary mechanisms: isomerization, fragmentation, and H/H2 loss...
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Optimization of Single-Sided Lapping Kinematics Based on Statistical Analysis of Abrasive Particles Trajectories
PublikacjaThe chapter presents the influence of selected kinematic parameters on the geometrical results of the single-sided lapping process. The optimization of these parameters is aimed at improving the quality and flatness of the machined surfaces. The uniformity of tool wear was assumed as main optimization criterion. Lapping plate wear model was created and in detail was analyzed. A Matlab program was designed to simulate the abrasive...
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Application of gamma densitometry and statistical signal analysis to gas phase velocity measurements in pipeline hydrotransport
PublikacjaThe work presents selected methods of signal analysis used in the processing of data obtained from radiometric probes. The used data came from an exemplary study of a two-phase liquid-gas flow at the laboratory installation. In such rigs many possible transport types may be observed, i.e. slug, plug and bubble flow, and each of them gives different signal-to-noise ratio of recorded data. Therefore, available radiometric methods...
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Application of gamma densitometry and statistical signal analysis to gas phase velocity measurements in pipeline hydrotransport
PublikacjaThe work presents selected methods of signal analysis used in the processing of data obtained from radiometric probes. The used data came from an exemplary study of a two-phase liquid-gas flow at the laboratory installation. In such rigs many possible transport types may be observed, i.e. slug, plug and bubble flow, and each of them gives different signal-to-noise ratio of recorded data. Therefore, available radiometric methods...
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Example applications of control charts as a quality tool for statistical process control in a small manufacturing company
PublikacjaPraca zawiera przykład wdrożenia kart kontrolnych w małym zakładzie produkcyjnym zajmującym się wytwarzaniem komponentów z blach. Pokazano jak z zastosowaniem dostępnego pakietu biurowego, można stworzyć statystyczną kontrolę procesu(SPC)w małej firmie. Artykuł zawiera wyniki z przykładowych analizowanych procesów.
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FE-investigations of a deterministic and statistical size effect in granular bodies within a micro-polar hypoplasticity
PublikacjaArtykuł omawia deterministyczny i statystyczny efekt skali w materiałach granulowanych podczas ścinania cienkiej warstwy piasku między dwoma bardzo szorstkimi ścianami. Obliczenia wykonano metodą elementów skończonych na bazie mikropolarnego prawa hipoplastycznego. Przyjęto różne wysokości warstw.
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Deterministic and statistical size effect during shearing of granular layer within a micro-polar hypoplasticity
PublikacjaArtykuł omawia deterministyczny i statystyczny efekt skali w materiałach granulowanych podczas ścinania cienkiej warstwy piasku między dwoma bardzo szorstkimi ścianami. Obliczenia wykonano metodą elementów skończonych na bazie mikropolarnego prawa hipoplastycznego. Przyjęto różne metody redukujące ilość realizacji pól losowych dla początkowego wskaźnika porowatości..
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Variable-fidelity response feature surrogates for accelerated statistical analysis and yield estimation of compact microwave components
PublikacjaAccounting for manufacturing tolerances is an essential part of a reliable microwave design process. Yet, quantification of geometry and/or material parameter uncertainties is challenging at the level of full-wave electromagnetic (EM) simulation models. This is due to inherently high cost of EM analysis and massive simulations necessary to conduct the statistical analysis. Here, a low-cost and accurate yield estimation procedure...
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Flavonoids as tyrosinase inhibitors in in silico and in vitro models: basic framework of SAR using a statistical modelling approach
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Catching-up and club convergence from cross-national perspective. A statistical study for the period 1980-2010
PublikacjaArtykuł o charakterze empirycznym, w którym podjęto analizę konwergencji 101 gospodarek świata pod względem poziomu PKB per capita. Analizę przeprowadzono dla lat 1980-2010. Dodatkowo, w ramach analizy empirycznej, zidentyfikowano tzw. kluby konwergencji ekonomicznej, tj. grupy krajów, które ''zbliżały się'' do siebie pod względem poziomu rozwoju gospodarczego w latach 1980-2010.
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Parametric FE studies on a coupled energetic-statistical size effect in plain concrete beams under bending
PublikacjaW artykule omówiono wyniki połączonego deterministyczno-statystycznego efektu skali w betonowych belkach podczas zginania. Obliczenia wykonano stosując MES w zakresie sprężysto-plastyczności z nielokalnym osłabieniem. Obliczenia wykonano dla różnych długości korelacji i współczynnika zmienności.
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FE analysis of a coupled energetic-statistical size effect in plain concrete beams with varying material properties.
PublikacjaThe numerical FE investigations of a coupled energetic-statistical size effect in unnotched concrete beams of similar geometry under quasi-static three point bending were performed within elasto-plasticity with non-local softening. The stochastic FE analyses were carried out with three different beam sizes. Deterministic calculations were performed with the uniform distribution of a uniaxial tensile strength. In statistical calculations...
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Statistical optimization of the synthesis of plant-derived fatty acid esters of TMP over homogeneous organometallic tin catalyst
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Sustainable Development and Motivation Opportunities from the Perspective of Women in the Polish Science Sector in the Light of Statistical Data and Surveys
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Statistical process control in software project management : a way to transfer single incident-related knowledge into organizational knowledge
PublikacjaZaproponowano statystyczne podejście do procesu kontroli zarządzania projektami informatycznymi. Przedstawiono sposób zamiany wiedzy incydentalnej na wiedzę organizacyjną.
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Using Statistical Methods to Estimate The Worst Case Response Time of Network Software Running on Indeterministic Hardware Platforms
PublikacjaIn this paper we investigate whether the statistical Worst Case Execution Time (WCET) estimation methods devised for embedded platforms can be successfully applied to find the Worst Case Response Time (WCRT) of a network application running on a complex hardware platform such as a contemporary commercial off-the-shelf (COTS) system. Establishing easy-to-use timing validation techniques is crucial for real-time applications and...
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The Presidential Campaign of Małgorzata Kidawa-Błońska in Media Discourse: Analysis Based on Statistical Corpus Analysis and Topic Modelling
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Computationally-Efficient Statistical Design and Yield Optimization of Resonator-Based Notch Filters Using Feature-Based Surrogates
PublikacjaModern microwave devices are designed to fulfill stringent requirements pertaining to electrical performance, which requires, among others, a meticulous tuning of their geometry parameters. When moving up in frequency, physical dimensions of passive microwave circuits become smaller, making the system performance increasingly susceptible to manufacturing tolerances. In particular, inherent inaccuracy of fabrication processes affect...
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Multivariate Statistical Analysis for Mutual Dependence Assessment of Selected Polyphenols, Organic Acids and Metals in Cool-Climate Wines
PublikacjaPolyphenols, organic acids and metal ions are an important group of compounds that affect the human health and quality of food and beverage products, including wines. It is known that a specific correlation between these groups exist. While wines coming from the New World and the Old World countries are extensively studied, wines coming from cool-climate countries are rarely discussed in the literature. One of the goals of this...
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FE investigations of the effect of fluctuating local tensile strength on coupled energetic-statistical size effect in concrete beams
PublikacjaThe effect of fluctuating local tensile strength on a coupled energetic-statistical size effect in plain concrete beams under bending was numerically investigated. First, the influence of varying autocorrelation length of the random field describing a spatial variation of local tensile strength was studied. Next, the influence of the coefficient of variation of local tensile strength was analyzed. The numerical FE investigations...