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1	Statistický software pro analýzu časových řad Sianchuk, Raman January 2008 (has links) Vzhledem k existenci obrovského množství statistických programů vzniká docela logická otázka: který z nich je lepší. Samozřejmě tady záleží na konkrétní zkoumané úloze. V této práci se budu věnovat analýze časových řad. Vzhledem k tomu, že na trhu jsou jak placené tak i neplacené programy bude třeba se podívat na několik představitelů obou skupin. Závěrem své práce ohodnotím tyto softwary podle několika kritérii. Posuzovat budu z hlediska potřeb studenta Vysoké Školy Ekonomické. Studenti VŠE tady mají možnost pracovat především se Statgraphicsem a GiveWinem, další dva softwary Matrixer a Gretl jsou zprostředkovány jako freeware a jsou dostupné zdarma na internetu, dále budu porovnávat i placené programy EViews a Time Series Modelling, s cílem posoudit jestli se vyplatí koupit licenci na tyto softwary nebo je lepší použít školní program anebo bude lepší stáhnout freeware. Rozbor programu provedu pomocí tři aspektů: obecný popis programů, příkladu ARIMA a příkladu SARIMA.
2	Neparametrické testy v statistickém software / Nonparametric tests in statistical software Skolil, Lukáš January 2007 (has links) Cílem této diplomové práce je praktické i teoretické seznámení uživatelů neparametrických metod s několika vybranými statistickými programy, v nichž je možné neparametrické analýzy provádět. Nedílnou součástí cíle je i porovnání těchto programů. V teoretické části jsou stručně popsány základy testování statistických hypotéz a teorie neparametrických testů. V praktické části jsou prozkoumány programy NCSS 2007, Statistica 7, SPSS 15, Systat 12, Stagraphics Centurion XV, Minitab 15, S-Plus 6.2, SAS 9.1 a StatXact 7. U každého software jsou popsány neparametrické testy, které obsahuje, a zjednodušeně i vkládání dat a výstupy. Nakonec jsou vybrané programy porovnány z několika hledisek. Všechny vybrané programy obsahují značné množství neparametrických testů a liší se většinou jen v detailech. Pro většinu analýz není potřeba hledat speciální programy a dají se použít všechny vybrané, pouze pro porovnávání rozptylů je nutné použít buď SAS nebo StatXact, protože v jiných programech ve výběru tyto testy nenalezneme.
3	Automatic measurement of particles from holograms taken in the combustion chamber of a rocket motor Carrier, Denis Joseph Gaston 12 1900 (has links) Approved for public release; distribution is unlimited / This thesis describes the procedure used for the automatic measurement of particles from hologram taken in the combustion chamber of a rocket motor while firing. It describes the investigation done on two averaging techniques used to reduce speckle noise, capturing the image focused on a spinning mylar disk and software averaging of several image frames. The spinning disk technique proved superior for this application. The Kolmogorov-Smirnov two-sample test is applied to different particle samples in order to find an estimate of the number of particles required to obtain a stable distribution function. The number of particles is calculated and given. The last part of this study shows real particle distributions in the form of frequency histograms. / http://archive.org/details/automaticmeasure00carr / Major, Canadian Armed Forces Statgraphics Hologram Mylar disk Averaging Frequency histogram Kolmogorov-Smirnov Test Imageaction Particle distribution
4	[en] CONSERVATIVE MANAGED ENTERPRISES: DEMAND FORECAST AND COMPUTER SIMULATION POTENTIAL / [pt] EMPRESAS DE GESTÃO CONSERVADORA: POTENCIAL DA PREVISÃO DE DEMANDA E SIMULAÇÃO COMPUTACIONAL ALEXANDRE MAGNO CASTANON GUIMARAES 14 June 2017 (has links) [pt] Esta dissertação tem como objetivo mostrar o potencial da aplicação das ferramentas Previsão de Demanda e Simulação Computacional em uma unidade produtiva com administração de característica familiar, que não adota as modernas técnicas propostas por especialistas para a gestão da cadeia de suprimento. Para isso, foram abordados os conceitos e os aspectos fundamentais, bem como as principais etapas, os benefícios, as limitações e as dificuldades da utilização dessas ferramentas. Além disso, foi proposta uma metodologia que aumentou a precisão da Previsão de Demanda. Com os dados obtidos foi possível analisar o desempenho dos fluxos dos processos simulados, o que permite auxiliar na gestão dos recursos, levando-se em conta principalmente a variabilidade da demanda e as incertezas dos mercados. Nessas análises foram utilizados os softwares Statgraphics Centurion e Arena a fim de elaborar, respectivamente, os modelos de previsão de demanda e de simulação computacional para o estudo de caso proposto. / [en] This thesis aims to show the potential of the Demand Forecast and Computer Simulation techniques carried out in a manufacturing plant with family administration feature that does not use the modern techniques proposed by Supply Chain management experts. In order to study the subject; concepts, fundamental principles, important steps, advantages, limitations as well as the difficulties of using those tools were investigated. In addition, a new method was proposed which resulted in the improvement of the demand forecast accuracy. With the forecasted data, it was possible to analyze the performance of the simulated manufacture flows. Such procedures improved the management of resources while the demand variability and the uncertainties of markets were considered. The Statgraphics Centurion and Arena softwares were used in order to developed, respectively, models for Demand Forecast and Computer Simulation for the study proposed. [pt] SERIES TEMPORAIS [en] TIME SERIES [pt] PREVISAO [en] FORECASTING [pt] DEMANDA [en] DEMAND [pt] SIMULACAO [en] SIMULATION [pt] RECURSOS [en] RESOURCES [pt] ARENA [pt] STATGRAPHICS
5	Atrial Fibrillation Detection Algorithm Evaluation and Implementation in Java / Utvärdering av algoritmer för detektion av förmaksflimmer samt implementation i Java Dizon, Lucas, Johansson, Martin January 2014 (has links) Atrial fibrillation is a common heart arrhythmia which is characterized by a missing or irregular contraction of the atria. The disease is a risk factor for other more serious diseases and the total medical costs in society are extensive. Therefore it would be beneficial to improve and optimize the prevention and detection of the disease. Pulse palpation and heart auscultation can facilitate the detection of atrial fibrillation clinically, but the diagnosis is generally confirmed by an ECG examination. Today there are several algorithms that detect atrial fibrillation by analysing an ECG. A common method is to study the heart rate variability (HRV) and by different types of statistical calculations find episodes of atrial fibrillation which deviates from normal sinus rhythm. Two algorithms for detection of atrial fibrillation have been evaluated in Matlab. One is based on the coefficient of variation and the other uses a logistic regression model. Training and testing of the algorithms were done with data from the Physionet MIT database. Several steps of signal processing were used to remove different types of noise and artefacts before the data could be used. When testing the algorithms, the CV algorithm performed with a sensitivity of 91,38%, a specificity of 93,93% and accuracy of 92,92%, and the results of the logistic regression algorithm was a sensitivity of 97,23%, specificity of 93,79% and accuracy of 95,39%. The logistic regression algorithm performed better and was chosen for implementation in Java, where it achieved a sensitivity of 97,31%, specificity of 93,47% and accuracy of 95,25%. / Förmaksflimmer är en vanlig hjärtrytmrubbning som kännetecknas av en avsaknad eller oregelbunden kontraktion av förmaken. Sjukdomen är en riskfaktor för andra allvarligare sjukdomar och de totala kostnaderna för samhället är betydande. Det skulle därför vara fördelaktigt att effektivisera och förbättra prevention samt diagnostisering av förmaksflimmer. Kliniskt diagnostiseras förmaksflimmer med hjälp av till exempel pulspalpation och auskultation av hjärtat, men diagnosen brukar fastställas med en EKG-undersökning. Det finns idag flertalet algoritmer för att detektera arytmin genom att analysera ett EKG. En av de vanligaste metoderna är att undersöka variabiliteten av hjärtrytmen (HRV) och utföra olika sorters statistiska beräkningar som kan upptäcka episoder av förmaksflimmer som avviker från en normal sinusrytm. I detta projekt har två metoder för att detektera förmaksflimmer utvärderats i Matlab, en baseras på beräkningar av variationskoefficienten och den andra använder sig av logistisk regression. EKG som kommer från databasen Physionet MIT används för att träna och testa modeller av algoritmerna. Innan EKG-signalen kan användas måste den behandlas för att ta bort olika typer av brus och artefakter. Vid test av algoritmen med variationskoefficienten blev resultatet en sensitivitet på 91,38%, en specificitet på 93,93% och en noggrannhet på 92,92%. För logistisk regression blev sensitiviteten 97,23%, specificiteten 93,79% och noggrannheten 95,39%. Algoritmen med logistisk regression presterade bättre och valdes därför för att implementeras i Java, där uppnåddes en sensitivitet på 91,31%, en specificitet på 93,47% och en noggrannhet på 95,25%. Atrial Fibrillation AF Detection algorithm AF detection Algorithm evaluation Matlab Java Electrocardiogram ECG Heart rate variability HRV Signal processing Pre processing Noise reduction Baseline wander powerline interference wavelet transform DWT R-peak detection Pan-tompkins HRV cleaning Feature selection U-test SDANN SDNN CV RMSSD PNN50 TINN LF HF Logistic regression CV algorithm Receiver operating characteristics ROC Classification Confusion matrix Leave-one-out cross validation Statgraphics Förmaksflimmer detekteringsalgoritm evaluering Matlab Java elektrokardiogram EKG Hjärtfrekvens variabilitet Signalbehandling Brusreducering Logistisk regression Variationskoefficient Klassificering Medical Engineering Medicinteknik

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