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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Lexikální aspekty kubánské španělštiny / Lexical aspects of Cuban Spanish

Schumannová, Klára January 2016 (has links)
(in English): The topic of the present thesis is the lexical aspects of Cuban Spanish, primarily the influence of other languages on its vocabulary. The theoretical part is dedicated to the historical and cultural circumstances of the history of the Cuban variant of Spanish, it briefly outlines the evolution of the Cuban lexicography and, most importantly, it pays attention to the impact of other languages: Spanish of the conquerors, Indian languages, African languages, French, English, Chinese and Russian on Cuban lexis. In addition, a short part of the thesis is dedicated to the sociolinguistic situation in Cuba. The theoretical background serves as the basis for the practical part of the thesis, in which the occurrence of selected lexical items in the linguistics corpora CREA, CORPES XXI and Araneum Hispanicum Maius is examined.
82

Restauration d'images 3D de microscopie de fluorescence en présence d'aberrations optiques / Restoration of 3D fluorescence microscopy images under the presence of optical aberrations

Ben Hadj, Saïma 17 April 2013 (has links)
Dans cette thèse, nous nous intéressons à la restauration d'image tridimensionnelle de microscopie de fluorescence. Deux difficultés majeures dans ce système d'imagerie sont traitées. La première est le flou variable en profondeur qui est dû aux aberrations induites par la variation des indices de réfraction dans le système optique et le spécimen imagé. La deuxième est le bruit qui est principalement dû au processus de comptage de photons. L'objectif de cette thèse est de réduire ces distorsions afin de fournir aux biologistes une image de meilleure qualité possible. Dans la première partie de cette thèse, nous étudions les modèles d'approximation du flou variable en profondeur et nous choisissons un modèle adéquat au problème d'inversion. Dans ce modèle, la réponse impulsionnelle (RI) variable en profondeur est approchée par une combinaison convexe d'un ensemble de RIs invariables spatialement. Nous développons pour ce modèle deux méthodes rapides de restauration non-aveugle par minimisation d'un critère régularisé, chacune d'elles est adaptée au type de bruit présent dans les images de microscopie confocale ou à champ large. Dans la deuxième partie, nous abordons le problème de restauration aveugle et proposons deux méthodes dans lesquelles le flou variable en profondeur et l'image sont conjointement estimés. Dans la première méthode, la RI est estimée en chaque voxel du volume considéré afin de laisser une grande liberté sur la forme de la RI, tandis que dans la deuxième méthode, la forme de la RI est contrainte par une fonction gaussienne afin de réduire le nombre de variables inconnues et l'espace des solutions possibles. Dans ces deux méthodes d'estimation aveugle, l'effet des aberrations optiques n'est pas efficacement estimé en raison du manque d'information. Nous améliorons ces méthodes d'estimation en alternant des contraintes dans les domaines fréquentiel et spatial. Des résultats sont montrés en simulation et sur des données réelles. / In this thesis, we focus on the restoration of three-dimensional image of fluorescence microscopy. Two major difficulties in this imaging system are considered. The first one is the depth-variant blur due to aberrations induced by the refractive index variation in the optical system and the imaged specimen. The second difficulty is the noise due to the photon counting process. The goal of this thesis is to reduce these distortions in order to provide biologists with a better image quality. In the first part of this thesis, we study the approximation models of the depth-variant blur and choose an appropriate model for the inversion problem. In that model, the depth-variant point spread function (PSF) is approximated by a convex combination of a set of space-invariant PSFs. We then develop for that model two fast non-blind restoration methods by minimizing a regularized criterion, each of these methods is adapted to the type of noise present in images of confocal or wide field microscopy. In the second part, we address the problem of blind restoration and propose two methods where the depth-variant blur and the image are jointly estimated. In the first method, the PSF is estimated at each voxel in the considered volume in order to allow high degree of freedom on the PSF shape while in the second method, the shape of the PSF is constrained by a Gaussian function in order to reduce the number of unknown variables and the space of possible solutions. In both blind estimation methods, the effect of optical aberrations is not effectively estimated due to the lack of information. We thus improve these estimation methods by alternating some constraints in the frequency and spatial domains. Results on simulated and real data are shown.
83

Systém pro řešení úloh vícekriteriálního hodnocení variant v prostředí internetu / Systém pro řešení úloh vícekriteriálního hodnocení variant v prostředí internetu

Zavrtálek, Jan January 2009 (has links)
This diploma thesis deals with description of methods and original on-line application for solving multicriteria evaluation of alternatives problems. Methods based on maximisation of utility value (WSA), minimisation of distance from ideal alternative (TOPSIS), evaluation of preference relations (ELECTRE) and evaluation along preference flows (PROMETHEE) are described and implemented in the application. The thesis introduces an original web application written in PHP language which is developed for solving multicriteria evaluation of alternatives problems in internet environment. The application running on web-server allows solving multicriteria evaluation of alternatives problems by four above mentioned methods. The application is controlled by any web browser. A run-time complexity of used algorithms is measured and discussed.
84

Managing product family variance : Development of product family architecture and its realization in a PLM system / Hantering av varians i produktfamiljer : Utveckling av produktfamilj-arkitektur och dess realisering i ett PLM system

Petersson, Rickard January 2019 (has links)
No description available.
85

Tvorba výnosu a kvalita ozimé pšenice v podmínkách setrvalého pěstování / The yield formation and quality of winter wheat in low-input conditions

PAVLÁTOVÁ, Kristýna January 2019 (has links)
The aim of this thesis is to evaluate basic yield formation and food quality of grain in selected winter wheat varieties, depending on the intensity of cultivation. There was 5 varieties chosen for the experiment of which 3 was linear (Patras, Turandot and Rumor) and 2 varieties was hybrid (Hyfi and Hybery). Each variety was repeated three times during the experiment. The vegetation was assessed in two variations - the checking one and the one fertilized by the nitrogen. This experiment was conducted in growing season 2017/2018 on the field of Faculty of Agriculture of University of South Bohemia. The withdrawal of the vegetal material for the purpose of the following sample analysis was done right before the harvesting. The yield formation and the health condition of the vegetation was assessed in the fieldwork. The determination of qualitative parameters was made with the help of the apparatus in the laboratory of the faculty. Then, the results was marked in tables and graphics. Finally, the statistical evaluation of the obtained data. An average yield of all assessed varieties of the winter wheat was 8,52 t.ha-1 at the checking variation. On the contrary, at the nitrogen fertilized one the average yield was 8,94 t.ha-1. The evaluated varieties in the growing season 2017/2018 had the baking quality A and B. Regarding the qualitative parameters, there was found lower values of volume quantity than those that are stated in the norm for the food wheat (at least 76,0 kg.hl-1). The highest values were found at the variety Turandot fertilized by nitrogen (77,8 kg.hl-1), which met the requirements of the ČSN 4611 00-2.
86

O léxico guiratinguense na perspectiva dialetológica: aspectos semântico-lexicais / The lexicon of Guiratinga in dialectology perspective : semantic-lexical aspects

Viola, Wanderléia Silva Carvalho 01 October 2010 (has links)
O presente estudo tem por objetivo registrar a variação dialetal no léxico do município de Guiratinga-MT. Para isto utilizou-se do Questionário Semântico-Lexical do projeto ALiB, versão 2001, na recolha in loco do corpus, a qual se deu em conformidade com os princípios metodológicos da Geolinguística atual, em três pontos do município: a sede e dois distritos.Na sede foram entrevistados 05 homens e 05 mulheres em cada uma das quatro faixas etárias estabelecidas: acima de 65 anos, 50/64 anos, 35/49 anos e 20/34 anos; no distrito 1, Alcantilado, entrevistaram-se 02 homens e 02 mulheres em cada faixa etária; no distrito 2, Vale Rico, os sujeitos entrevistados foram 03 homens e 03 mulheres, também naquelas faixas etárias. Os dados obtidos a partir dessas respostas estão em tabelas nas quais consideram ponto linguístico, faixa etária, gênero e frequência absoluta e relativa de acordo com as noções de estatística lexical de Muller. Ao final de cada área semântica expõem-se as lexias mais frequentes em histogramas, e a seguir se dão as análises, privilegiando a abordagem semântico-lexical, com base em Rastier semas inerentes e aferentes , a partir da concepção de norma de Coseriu. Enfim, a pesquisa apresenta a realidade linguística de um pequeno município do centro-oeste do Brasil, antes que ela se perca pela ação natural de dinâmica e mutabilidade da própria língua ou por questões denominadas homogeneizadoras. / The present study has as aim to register the lexical dialectal variation of Guiratinga-MT; In order to reach that objective, the Semantics-Lexical Questionnaire, of the ALiB project, version 2001, was used during the collection of corpus in loco, according to the current Geolinguistics methodological principles, in three sites: the headquarter (the town) and two districts. In the headquarter, 5 men and 5 women from each of the following age categories were interviewed: over 65 years old, 50/64 years old, 35/49 years old and 20/34 years old; in the first district, Alcantilado, 2 men and 2 women of those age categories were interviewed. The obtained data are in tables which consider linguistics point, age, gender, and, absolute and relative frequency, in accordance to Mullers lexical statistics notion. At the end of each semantical field, the most frequent lexis were exposed in histograms, followed by analysis, granting the semantical lexical approach, based on Rastier inherent and afferent semas from the model conception of Coseriu. Finally, the study presents the linguistics reality of a small town in the Brazilian Midwest, before it disappears because of the natural action of dynamics and changeability of the own language, or because of homogenizing matters.
87

Statistical Methods for Characterizing Genomic Heterogeneity in Mixed Samples

Zhang, Fan 12 December 2016 (has links)
"Recently, sequencing technologies have generated massive and heterogeneous data sets. However, interpretation of these data sets is a major barrier to understand genomic heterogeneity in complex diseases. In this dissertation, we develop a Bayesian statistical method for single nucleotide level analysis and a global optimization method for gene expression level analysis to characterize genomic heterogeneity in mixed samples. The detection of rare single nucleotide variants (SNVs) is important for understanding genetic heterogeneity using next-generation sequencing (NGS) data. Various computational algorithms have been proposed to detect variants at the single nucleotide level in mixed samples. Yet, the noise inherent in the biological processes involved in NGS technology necessitates the development of statistically accurate methods to identify true rare variants. At the single nucleotide level, we propose a Bayesian probabilistic model and a variational expectation maximization (EM) algorithm to estimate non-reference allele frequency (NRAF) and identify SNVs in heterogeneous cell populations. We demonstrate that our variational EM algorithm has comparable sensitivity and specificity compared with a Markov Chain Monte Carlo (MCMC) sampling inference algorithm, and is more computationally efficient on tests of relatively low coverage (27x and 298x) data. Furthermore, we show that our model with a variational EM inference algorithm has higher specificity than many state-of-the-art algorithms. In an analysis of a directed evolution longitudinal yeast data set, we are able to identify a time-series trend in non-reference allele frequency and detect novel variants that have not yet been reported. Our model also detects the emergence of a beneficial variant earlier than was previously shown, and a pair of concomitant variants. Characterization of heterogeneity in gene expression data is a critical challenge for personalized treatment and drug resistance due to intra-tumor heterogeneity. Mixed membership factorization has become popular for analyzing data sets that have within-sample heterogeneity. In recent years, several algorithms have been developed for mixed membership matrix factorization, but they only guarantee estimates from a local optimum. At the gene expression level, we derive a global optimization (GOP) algorithm that provides a guaranteed epsilon-global optimum for a sparse mixed membership matrix factorization problem for molecular subtype classification. We test the algorithm on simulated data and find the algorithm always bounds the global optimum across random initializations and explores multiple modes efficiently. The GOP algorithm is well-suited for parallel computations in the key optimization steps. "
88

Uma abordagem baseada em texels para síntese de texturas que variam progressivamente

Tonietto, Leandro 02 March 2005 (has links)
Made available in DSpace on 2015-03-05T13:53:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este trabalho apresenta um modelo para síntese de texturas a partir de amostras, mais especificamente para síntese de texturas com elementos que variam progressivamente ao longo da textura, conhecidas como Progressively-Variant Textures (PVT). Este tipo de textura é comum na Natureza, particularmente na pelagem de animais como leopardos. Os algoritmos de síntese existentes, na grande maioria, não permitem qualquer controle sobre o resultado final, ou então, os que permitem, são limitados ou tem problemas de performance inerente ao método de síntese utilizado (pixel-a-pixel). Para resolvermos estes problemas, propomos um algoritmo baseado numa nova unidade de síntese: o texel. O nosso algoritmo sintetiza uma nova textura agrupando texels que satisfazem um critério de similaridade numa vizinhança. As características de uma PVT são obtidas com transformações afim e operações morfológicas aplicadas sobre os texels e definidas pelo usuário. Os resultados obtidos apresentam uma ótima qualidade visual para uma / We present a model for texture synthesis from samples, particularly for synthesis of textures with smooth variation of the texture elements, known as Progressively-Variant Textures (PVT). This type of textures is common in Nature, specially in animal coat markings such as leopards. Current solutions, for the most part, do not allow much control by the user or the ones which do allow control are limited or have problems due to the pixel-at-a-time nature of synthesis. We address these problems with the introduction of an algorithm based on a new building block for synthesis: the texel. Our solution builds a new texture grouping texels which satisfy a neighborhood similarity criterion. The PVT features are introduced with affine transformations and morphological operators defined by the user and applied to the texels. The results show a good visual quality for a large number of sample textures, including cases where current solutions for natural textures fail. Besides, the many possibilities for variation of te
89

The effect of the cyclin G-associated kinase on the pathogenesis of Parkinson's disease

Nagle, Michael William 22 January 2016 (has links)
Parkinson's Disease (PD) is the second most common neurodegenerative disorder, clinically characterized by severe motor impairment and pathologically characterized by progressive loss of the dopaminergic neurons of the substantia nigra pars compacta (SNpc) as well as the formation of cellular aggregate deposits called Lewy Bodies. While some advances have been made in understanding the molecular underpinnings of the disorder, the molecular implications of common genetic factors increasing risk for PD have not been adequately studied. First identified by GWA studies in 2009, the GAK/DGKQ/IDUA region on chromosome 4p16.3 shows significant genetic association to risk for PD, and the GAK protein has been shown to be associated with the primary component of Lewy Bodies, a-synuclein. In order to determine which gene in the 4p16.3 region may account for the genetic association to PD and to understand the molecular consequences of that association, post-mortem cortical brain tissue from 29 PD and 49 control patients was RNA-sequenced and differential exon usage in the context of disease and risk variant carrier status was analyzed. Exons in the 3' region of GAK were found to be associated to case status, and notably exon 25 expression in GAK was associated with both case status and the risk variant. This exon was further observed to be associated to several genes previously shown to interact with GAK, including SNCA, which codes for a-synuclein. As a proxy for expression of the 3' region of GAK, exon 25 was assessed for genome-wide association, and genes showing association to the exon were involved in pathways related to synaptic transmission and neuronal function. In order to validate these findings, microarray analysis of primary rat cortical neurons in which GAK expression was reduced by shRNA transduction was performed. GAK expression in rat neurons was significantly inversely correlated to endogenous SNCA expression, and also exhibited association to pathways involved in synaptic transmission and mitochondrial function. Together, these findings suggest aberrant GAK expression related to genetic risk to be an important factor in the pathogenesis of PD through GAK's influence on SNCA expression and through dysregulation of important neuronal pathways.
90

Praktické využití metod vícekriteriálního rozhodování v aplikaci na výběr stavebního materiálu / Practical utilisation of multi-criteria decision-making methods applied to the selection of construction material

Hrnčířová, Barbora January 2007 (has links)
Předmětem diplomové práce je výběr vhodného materiálu na stavbu. Metodika je založena na vícekriteriálním hodnocení variant. Při výběru materiálu na stavbu musíme vzít v potaz velké množství kritérií, jedná se jak o kritéria ekonomická, jako je cena, tak především o kritéria technická. Cílem diplomové práce je jednak samotný výběr vhodného materiálu, jednak ověření možnosti použití metod vícekriteriálního hodnocení variant v praxi a případně odhalení jejich nevýhod a nedostatků při srovnání výsledků jednotlivých metod. Práce také ukazuje, že jednodušší modely vícekriteriálního hodnocení variant se dají snadno použít v praxi.

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