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Search for Cosmic Sources of High Energy Neutrinos with the AMANDA-II Detector Recherche de sources cosmiques de neutrinos à haute énergie avec le détecteur AMANDA-IILabare, Mathieu 26 January 2010 (has links)
AMANDA-II est un télescope à neutrinos composé d'un réseau tri-dimensionnel de senseurs optiques déployé dans la glace du Pôle Sud.
Son principe de détection repose sur la mise en évidence de particules secondaires chargées émises lors de l'interaction d'un neutrino de haute énergie (> 100 GeV) avec la matière environnant le détecteur, sur base de la détection de rayonnement Cerenkov.
Ce travail est basé sur les données enregistrées par AMANDA-II entre 2000 et 2006, afin de rechercher des sources cosmiques de neutrinos.
Le signal recherché est affecté d'un bruit de fond important de muons et de neutrinos issus de l'interaction du rayonnement cosmique primaire dans l'atmosphère. En se limitant à l'observation de l'hémisphère nord, le bruit de fond des muons atmosphériques, absorbés par la Terre, est éliminé.
Par contre, les neutrinos atmosphériques forment un bruit de fond irréductible constituant la majorité des 6100 événements sélectionnés pour cette analyse.
Il est cependant possible d'identifier une source ponctuelle de neutrinos cosmiques en recherchant un excès local se détachant du bruit de fond isotrope de neutrinos atmosphériques, couplé à une sélection basée sur l'énergie, dont le spectre est différent pour les deux catégories de neutrinos.
Une approche statistique originale est développée dans le but d'optimiser le pouvoir de détection de sources ponctuelles, tout en contrôlant le taux de fausses découvertes, donc le niveau de confiance d'une observation.
Cette méthode repose uniquement sur la connaissance de l'hypothèse de bruit de fond, sans aucune hypothèse sur le modèle de production de neutrinos par les sources recherchées. De plus, elle intègre naturellement la notion de facteur d'essai rencontrée dans le cadre de test d'hypothèses multiples.La procédure a été appliquée sur l'échantillon final d'évènements récoltés par AMANDA-II.
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MANDA-II is a neutrino telescope which comprises a three dimensional array of optical sensors deployed in the South Pole glacier.
Its principle rests on the detection of the Cherenkov radiation emitted by charged secondary particles produced by the interaction of a high energy neutrino (> 100 GeV) with the matter surrounding the detector.
This work is based on data recorded by the AMANDA-II detector between 2000 and 2006 in order to search for cosmic sources of neutrinos. A potential signal must be extracted from the overwhelming background of muons and neutrinos originating from the interaction of primary cosmic rays within the atmosphere.
The observation is limited to the northern hemisphere in order to be free of the atmospheric muon background, which is stopped by the Earth. However, atmospheric neutrinos constitute an irreducible background composing the main part of the 6100 events selected for this analysis.
It is nevertheless possible to identify a point source of cosmic neutrinos by looking for a local excess breaking away from the isotropic background of atmospheric neutrinos;
This search is coupled with a selection based on the energy, whose spectrum is different from that of the atmospheric neutrino background.
An original statistical approach has been developed in order to optimize the detection of point sources, whilst controlling the false discovery rate -- hence the confidence level -- of an observation. This method is based solely on the knowledge of the background hypothesis, without any assumption on the production model of neutrinos in sought sources. Moreover, the method naturally accounts for the trial factor inherent in multiple testing.The procedure was applied on the final sample of events collected by AMANDA-II.
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Detecting differentially expressed genes while controlling the false discovery rate for microarray dataJiao, Shuo. January 2009 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2009. / Title from title screen (site viewed March 2, 2010). PDF text: 100 p. : col. ill. ; 953 K. UMI publication number: AAT 3379821. Includes bibliographical references. Also available in microfilm and microfiche formats.
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Using Design of Experiments in Validation of a new calorimetric method for the specific heat capacity determinationBabaee Koochaksaraee, Sima, Ghahremanpour, Sara January 2009 (has links)
Total Quality Management as a holistic management system is widely practical inevery organization these days and one of the foundations of TQM which should betaken into account in all functions of the company is continuous improvement.Customer satisfaction is an important topic in which continuous improvement play akey role and leads to enhance it. Therefore, it is very worthwhile for the organizationto define the designing new products/methods based on recent and future customerneeds as one of its main activities.Generally, during the development and before launching a new product/method,validation is a useful process to improve the quality and establish the qualification ofthat product/method.This project was conducted to perform a validation for a new calorimetric method byuse of DOE (Design Of Experiments) in “SP Technical Research Institute of Sweden”.The study have presented the results of implementing DOE in such a way that thenew calorimetric method is validated; besides it could determine the best condition inwhich the intended results could be achieved.This thesis is a completion part of the master program in Industrial Engineering with aspecialization in Quality and Environmental Management at University of Borås.
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The relationship between pupil control ideology and typology of teacher referrals /Holt, Judith Suzanne Lemley. January 1993 (has links)
Thesis (Ph.D.)--University of Tulsa, 1993. / Includes bibliographical references (leaves 120-129).
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Search for cosmic sources of high energy neutrinos with the AMANDA-II detector / Recherche de sources cosmiques de neutrinos à haute énergie avec le détecteur AMANDA-IILabare, Mathieu 26 January 2010 (has links)
AMANDA-II est un télescope à neutrinos composé d'un réseau tri-dimensionnel de senseurs optiques déployé dans la glace du Pôle Sud.<p>Son principe de détection repose sur la mise en évidence de particules secondaires chargées émises lors de l'interaction d'un neutrino de haute énergie (> 100 GeV) avec la matière environnant le détecteur, sur base de la détection de rayonnement Cerenkov.<p><p>Ce travail est basé sur les données enregistrées par AMANDA-II entre 2000 et 2006, afin de rechercher des sources cosmiques de neutrinos.<p>Le signal recherché est affecté d'un bruit de fond important de muons et de neutrinos issus de l'interaction du rayonnement cosmique primaire dans l'atmosphère. En se limitant à l'observation de l'hémisphère nord, le bruit de fond des muons atmosphériques, absorbés par la Terre, est éliminé.<p>Par contre, les neutrinos atmosphériques forment un bruit de fond irréductible constituant la majorité des 6100 événements sélectionnés pour cette analyse.<p>Il est cependant possible d'identifier une source ponctuelle de neutrinos cosmiques en recherchant un excès local se détachant du bruit de fond isotrope de neutrinos atmosphériques, couplé à une sélection basée sur l'énergie, dont le spectre est différent pour les deux catégories de neutrinos.<p><p>Une approche statistique originale est développée dans le but d'optimiser le pouvoir de détection de sources ponctuelles, tout en contrôlant le taux de fausses découvertes, donc le niveau de confiance d'une observation.<p>Cette méthode repose uniquement sur la connaissance de l'hypothèse de bruit de fond, sans aucune hypothèse sur le modèle de production de neutrinos par les sources recherchées. De plus, elle intègre naturellement la notion de facteur d'essai rencontrée dans le cadre de test d'hypothèses multiples.La procédure a été appliquée sur l'échantillon final d'évènements récoltés par AMANDA-II.<p><p>---------<p><p>MANDA-II is a neutrino telescope which comprises a three dimensional array of optical sensors deployed in the South Pole glacier. <p>Its principle rests on the detection of the Cherenkov radiation emitted by charged secondary particles produced by the interaction of a high energy neutrino (> 100 GeV) with the matter surrounding the detector.<p><p>This work is based on data recorded by the AMANDA-II detector between 2000 and 2006 in order to search for cosmic sources of neutrinos. A potential signal must be extracted from the overwhelming background of muons and neutrinos originating from the interaction of primary cosmic rays within the atmosphere.<p>The observation is limited to the northern hemisphere in order to be free of the atmospheric muon background, which is stopped by the Earth. However, atmospheric neutrinos constitute an irreducible background composing the main part of the 6100 events selected for this analysis.<p>It is nevertheless possible to identify a point source of cosmic neutrinos by looking for a local excess breaking away from the isotropic background of atmospheric neutrinos;<p>This search is coupled with a selection based on the energy, whose spectrum is different from that of the atmospheric neutrino background.<p><p>An original statistical approach has been developed in order to optimize the detection of point sources, whilst controlling the false discovery rate -- hence the confidence level -- of an observation. This method is based solely on the knowledge of the background hypothesis, without any assumption on the production model of neutrinos in sought sources. Moreover, the method naturally accounts for the trial factor inherent in multiple testing.The procedure was applied on the final sample of events collected by AMANDA-II. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
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Decomposition of a set of distributions in extended exponential family form for distinguishing multiple oligo-dimensional marker expression profiles of single-cell populations and visualizing their dynamics / 分布セットの拡大指数型分布族形式への分解による、オリゴ次元マーカーを測定した複数の1細胞発現プロファイルの識別とそのダイナミクスの可視化Okada, Daigo 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(医科学) / 甲第23108号 / 医科博第119号 / 新制||医科||8(附属図書館) / 京都大学大学院医学研究科医科学専攻 / (主査)教授 藤渕 航, 教授 松田 道行, 教授 黒田 知宏 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
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ON THE PREDICTIVE PERFORMANCE OF THE STOCK RETURNS BY USING THE MARKOV-SWITCHING MODELSWu, Yanan January 2020 (has links)
This paper proposes the basic predictive regression and Markov Regime-Switching regression to predict the excess stock returns in both US and Sweden stock markets. The analysis shows that the Markov Regime-Switching regression models out perform the linear ones in out-of-sample forecasting, which is due to the fact that the regime-switching models capture the economic expansion and recession better.
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Development of an Electrical Impedance Tomography System for Breast Cancer and Applications of Multivariate Statistical Methods for Image Improvement / EIT System Development & Multivarite Image ImprovementJegatheesan, Aravinthan 12 1900 (has links)
This thesis consists of three sections, the first two deal with the development and testing of an electrical impedance tomography prototype system for imaging breast cancer. The third section sues mutlivariate statistical methods to improve EIT image quality. The McMaster EIT System Mk1.0 is the resultant system of the system development. The EIT system is a 48 electrode, single current source, serial acquisition device with an operational frequency between 100Hz to 125kHz. The device is able to inject current between any two electrodes and is able to perform single or differential measurements on any two electrode pairs. The system is equipped with a virtual phase-lock loop and is capable of paramatic imaging. The system was tested using tests common to most electrical devices and specifically designed for EIT systems, to both benchmark the system and detect any errors. The testing revealed the device while able to produce viable EIT images; system suffers from a large stray capacitance. Due to stray capacitance the system injection amplitude accuracy varies with frequency and load. The system SNR is over 100dB with a 125kHz signal with a 5mA signal and compares favourably with existing EIT systems. The CMRR of the system closely tracked the published CMRR of the underlying commercial components and is comparable to existing systems. A second source of error which needs to be rectified in future deigns is the high contact impedence; which causes high direct current offset. Multivariate testing was used to detect errors which could not be easily discovered using conventional testing. The testing, performed iteratively detected several electronic errors which were fixed during development of the device. Six related models were developed for system noise, each with a different set of underlying assumptions about the source of noise. Of the models only one model proved to be a success on both qualitative and quantitative analysis of sample data sets. Finally an alternate model to the Cole-Cole parametric imaging based on PCA was proposed. The model proved to be better at modeling the underlying tissue variations in the presence of noise than Cole-Cole based models. The prototype EIT system presented in this thesis is a viable EIT system, but is in need of improvements to shielding to improve system performance. Also in need of improvement is the operational frequency and modifications toward a distributed architecture. The multivariate methods used for modelling system noise and tissue should be combined into one method for maximum benefit. / Thesis / Master of Applied Science (MASc)
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Aspectos biométricos da detecção de QTL'S ("Quantitative Trait Loci") em espécies cultivadas. / Biometrical aspects of QTL detection in cultivated species.Silva, Heyder Diniz 05 December 2001 (has links)
O mapeamento de QTL's difere dos demais tipos de pesquisas conduzida em genética. Por se tratar basicamente de um procedimento de testes múltiplos, surge, neste contexto, um problema que se refere ao nível de significância conjunto da análise, e consequentemente, seu poder. Deste modo, avaliou-se, via simulação computacional de dados, o poder de detecção de QTL's da análise de marcas simples, realizada por meio de regressão linear múltipla, utilizando o procedimento stepwise" para seleção das marcas e procedimentos baseados em testes individuais, utilizando os critérios FDR e de Bonferroni para determinação nível de significância conjunto. Os resultados mostraram que o procedimento baseado em regressão múltipla, utilizando o procedimento stepwise" foi mais poderoso em identificar as marcas associadas a QTL's e, mesmo nos casos em que este procedimento apresentou poder ligeiramente inferior aos demais, verificou-se que o mesmo tem como grande vantagem selecionar apenas as marcas mais fortemente ligadas aos QTL's. Dentre os critérios FDR e de Bonferroni, o primeiro mostrou-se, em geral, mais poderoso, devendo ser adotado nos procedimentos de mapeamento por intervalo. Outro problema encontrado na análise de QTL's refere-se µa abordagem da interação QTL's x ambientes. Neste contexto, apresentou-se uma partição da variância da interação genótipos x ambientes em efeitos explicados pelos marcadores e desvios, a partir da qual obtiveram-se os estimadores da proporção da variância genética (pm), e da variância da interação genótipos x ambientes (pms), explicadas pelos marcadores moleculares. Estes estimadores independem de desvios das frequências alélicas dos marcadores em relação µ as esperadas (1:2:1 em uma geração F2, 1:1 em um retrocruzamento, etc.), porém, apresentam uma alta probabilidade de obtenção de estimativas fora do intervalo paramétrico, principalmente para valores elevados destas proporções. Contudo, estas probabilidades podem ser reduzidas com o aumento do número de repetições e/ou de ambientes nos quais as progênies são avaliadas. A partir de um conjunto de dados de produtividade de grãos, referentes µ a avaliação de 68 progênies de milho, genotipadas para 77 marcadores moleculares codominantes e avaliadas em quatro ambientes, verificou-se que as metodologias apresentadas permitiram estimar as proporções pm e pms, bem como classificar as marcas associadas a QTL's, conforme seu nível de interação. O procedimento permitiu ainda a identificação de regiões cromossômicas envolvidas no controle genético do caractere sob estudo conforme sua maior ou menor estabilidade ao longo dos ambientes. / In general terms, QTL mapping di®ers from other research ac-tivities in genetics. Being basically a multiple test procedure, problems arise which are related to the joint level of signi¯cance of the analysis, and consequently, to its power. Using computational simulation of data, the power of simple marker analysis, carried out through multiple linear regression, using stepwise procedures to select the markers was obtained. Procedures based on single tests, using both the FDR and the Bonferroni criteria to determinate the joint level of signi¯cance were also used. Results showed that the procedure based on multiple regression, using the stepwise technique, was the most powerful in identifying markers associated to QTL's. However, in cases where its power was smaller, its advantage was the ability to detect only markers strongly associates with QTL's. In comparision with the Bonferroni method, the FDR criterion was in general more powerful, and should be adopted in the interval mapping procedures. Additional problems found in the QTL analysis refer to the QTL x environment interaction. We consider this aspect by par-titioning the genotype x environment interaction variance in components explained by the molecular markers and deviations. This alowed estimating the proportion of the genetic variance (pm), and genotype x environment variance (pms), explained by the markers. These estimators are not a®ected by deviations of allelic frequencies of the markers in relation to the expected values (1:2:1 in a F2 generation, 1:1 in a backcross , etc). However, there is a high probability of obtaining estimates out of the parametric range, specially for high values of this proportion. Nevertheless, these probabilities can be reduced by increasing the number of replications and/or environments where the progenies are evaluated. Based on a set of grain yield data, obtained from the evaluation of 68 maize progenies genotyped for 77 codominant molecular markers, and evaluated as top crosses in four environments, the presented methodologies allowed estimating proportions pm and pms as well the classification of markers associated to QTL's, with respect to its level of genotype x environment interaction. The procedure also allowed the identification of chromosomic regions, involved in the genetical control of the considered trait, according to its stability, in relation to the observed environmental variation.
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Aspectos biométricos da detecção de QTL'S ("Quantitative Trait Loci") em espécies cultivadas. / Biometrical aspects of QTL detection in cultivated species.Heyder Diniz Silva 05 December 2001 (has links)
O mapeamento de QTL's difere dos demais tipos de pesquisas conduzida em genética. Por se tratar basicamente de um procedimento de testes múltiplos, surge, neste contexto, um problema que se refere ao nível de significância conjunto da análise, e consequentemente, seu poder. Deste modo, avaliou-se, via simulação computacional de dados, o poder de detecção de QTL's da análise de marcas simples, realizada por meio de regressão linear múltipla, utilizando o procedimento stepwise" para seleção das marcas e procedimentos baseados em testes individuais, utilizando os critérios FDR e de Bonferroni para determinação nível de significância conjunto. Os resultados mostraram que o procedimento baseado em regressão múltipla, utilizando o procedimento stepwise" foi mais poderoso em identificar as marcas associadas a QTL's e, mesmo nos casos em que este procedimento apresentou poder ligeiramente inferior aos demais, verificou-se que o mesmo tem como grande vantagem selecionar apenas as marcas mais fortemente ligadas aos QTL's. Dentre os critérios FDR e de Bonferroni, o primeiro mostrou-se, em geral, mais poderoso, devendo ser adotado nos procedimentos de mapeamento por intervalo. Outro problema encontrado na análise de QTL's refere-se µa abordagem da interação QTL's x ambientes. Neste contexto, apresentou-se uma partição da variância da interação genótipos x ambientes em efeitos explicados pelos marcadores e desvios, a partir da qual obtiveram-se os estimadores da proporção da variância genética (pm), e da variância da interação genótipos x ambientes (pms), explicadas pelos marcadores moleculares. Estes estimadores independem de desvios das frequências alélicas dos marcadores em relação µ as esperadas (1:2:1 em uma geração F2, 1:1 em um retrocruzamento, etc.), porém, apresentam uma alta probabilidade de obtenção de estimativas fora do intervalo paramétrico, principalmente para valores elevados destas proporções. Contudo, estas probabilidades podem ser reduzidas com o aumento do número de repetições e/ou de ambientes nos quais as progênies são avaliadas. A partir de um conjunto de dados de produtividade de grãos, referentes µ a avaliação de 68 progênies de milho, genotipadas para 77 marcadores moleculares codominantes e avaliadas em quatro ambientes, verificou-se que as metodologias apresentadas permitiram estimar as proporções pm e pms, bem como classificar as marcas associadas a QTL's, conforme seu nível de interação. O procedimento permitiu ainda a identificação de regiões cromossômicas envolvidas no controle genético do caractere sob estudo conforme sua maior ou menor estabilidade ao longo dos ambientes. / In general terms, QTL mapping di®ers from other research ac-tivities in genetics. Being basically a multiple test procedure, problems arise which are related to the joint level of signi¯cance of the analysis, and consequently, to its power. Using computational simulation of data, the power of simple marker analysis, carried out through multiple linear regression, using stepwise procedures to select the markers was obtained. Procedures based on single tests, using both the FDR and the Bonferroni criteria to determinate the joint level of signi¯cance were also used. Results showed that the procedure based on multiple regression, using the stepwise technique, was the most powerful in identifying markers associated to QTL's. However, in cases where its power was smaller, its advantage was the ability to detect only markers strongly associates with QTL's. In comparision with the Bonferroni method, the FDR criterion was in general more powerful, and should be adopted in the interval mapping procedures. Additional problems found in the QTL analysis refer to the QTL x environment interaction. We consider this aspect by par-titioning the genotype x environment interaction variance in components explained by the molecular markers and deviations. This alowed estimating the proportion of the genetic variance (pm), and genotype x environment variance (pms), explained by the markers. These estimators are not a®ected by deviations of allelic frequencies of the markers in relation to the expected values (1:2:1 in a F2 generation, 1:1 in a backcross , etc). However, there is a high probability of obtaining estimates out of the parametric range, specially for high values of this proportion. Nevertheless, these probabilities can be reduced by increasing the number of replications and/or environments where the progenies are evaluated. Based on a set of grain yield data, obtained from the evaluation of 68 maize progenies genotyped for 77 codominant molecular markers, and evaluated as top crosses in four environments, the presented methodologies allowed estimating proportions pm and pms as well the classification of markers associated to QTL's, with respect to its level of genotype x environment interaction. The procedure also allowed the identification of chromosomic regions, involved in the genetical control of the considered trait, according to its stability, in relation to the observed environmental variation.
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