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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.
201

Hadrons dans un calorimètre électromagnétique silicium-tungstène hautement granulaire - Production du quark top à l'International Linear Collider / Hadrons in a highly granular SiW ECAL – Top quark production at the ILC

Doublet, Philippe 03 October 2011 (has links)
L'International Linear Collider (ILC) est un projet de futur collisionneur électron positron opérant à une énergie nominale dans le centre de masse de 500 GeV. Il fera des mesures de précision, par exemple d'un boson de Higgs léger qui pourrait être bientôt découvert au Large Hadron Collider. Les détecteurs de l'ILC prévus à cet effet seront composés de calorimètres à haute granularité.Cette thèse présente l'étude de la réponse d'un calorimètre électromagnétique silicium tungstène hautement granulaire (ECAL SiW) ainsi que l'étude de la production du quark top à l'ILC.Le prototype d'un ECAL SiW développé par la collaboration CALICE a été testé sous faisceaux de particules chargées au FNAL en Mai et Juillet 2008. Après avoir sélectionné des pions chargés négativement et entrant dans le ECAL, sa haute granularité est mise à profit pour introduire une classification en quatre types d'événements, afin de décrire des interactions hadroniques.Des modèles de dimensions supplémentaires expliquent l'anomalie AFBb du LEP par une modification des couplages des quarks de troisième génération au boson Z. Ces effets motivent l'étude de la désintégration semileptonique des paires de quarks top, effectuée ici au moyen d'une simulation complète du détecteur ILD proposé pour l'ILC à une énergie dans le centre de masse de 500GeV pour une luminosité intégrée L = 500 fb-1. Les performances de ce détecteur permettent d'atteindre des efficacités de sélection de plus de 70% avec une pureté meilleure que 95%. Cela se traduit par une précision relative d'environ 1% sur l’asymétrie gauche-droite de la production du quark top ALR ainsi que sur l'asymétrie avant-arrière du quark top AFBt dans le cas où les électrons sont polarisés à 80% et pas les positrons. Les incertitudes relatives sur les couplages gauche et droit du quark top au boson Z peuvent aller jusqu'à 0.9% et 1.5%. / The International Linear Collider (ILC) is a proposed e+e- collider with a center-of-mass energy of 500 GeV or more, aimed at precision measurements, e.g. of a light Higgs boson that could be discovered soon at the Large Hadron Collider. Its detectors foresee the use of fine grained calorimeters to achieve the desired precisions.This thesis presents the study of the response to hadrons of a highly granular silicon-tungsten electromagnetic calorimeter (SiW ECAL), and the study of top quark pair production at the ILC.The SiW ECAL prototype developed by the CALICE collaboration was tested with beams of charged particles at FNAL in May and July 2008. After selecting single negatively charged pions entering the ECAL, its fine granularity is used to introduce a classification among four types of events, used to describe hadronic interactions.Motivated by extra-dimensional models which may explain the AFBb LEP anomaly by modifying the couplings of third generation quarks to the Z boson, the semileptonic decay of the top quark is studied with a full simulation of the proposed ILD detector for the ILC at center-of-mass energy of 500 GeV and integrated luminosity of 500 fb-1. Detector performances permit to reach efficiencies larger than 70% in finding those events with purity larger than 95%. This translates into a relative accuracy of about 1% on both the left-right asymmetry of top production ALR and the top forward-backward asymmetry AFBt with electrons polarized at 80% and no polarization of the positrons. The relative uncertainties in the left and right couplings of the top quark to the Z boson could be as good as 0.9% and 1.5%.
202

Advanced techniques for Web service query optimization / Techniques avancées pour l’optimisation de requêtes de services Web

Benouaret, Karim 09 October 2012 (has links)
De nos jours, nous assistons à l’émigration du Web de données vers le Web orienté services. L’amélioration des capacités et fonctionnalités des moteurs actuels de recherche sur le Web, par des techniques efficaces de recherche et de sélection de services, devient de plus en plus importante. Dans cette thèse, dans un premier temps, nous proposons un cadre de composition de services Web en tenant compte des préférences utilisateurs. Le modèle fondé sur la théorie des ensembles flous est utilisé pour représenter les préférences. L’approche proposée est basée sur une version étendue du principe d’optimalité de Pareto. Ainsi, la notion des top-k compositions est introduite pour répondre à des requêtes utilisateurs de nature complexe. Afin d’améliorer la qualité de l’ensemble des compositions retournées, un second filtre est appliqué à cet ensemble en utilisant le critère de diversité. Dans un second temps, nous avons considéré le problème de la sélection des services Web en présence de préférences émanant de plusieurs utilisateurs. Une nouvelle variante, appelée Skyline de services à majorité, du Skyline de services traditionnel est défini. Ce qui permet aux utilisateurs de prendre une décision « démocratique » conduisant aux services les plus appropriés. Un autre type de Skyline de services est également discuté dans cette thèse. Il s’agit d’un Skyline de Services de nature graduelle et se fonde sur une relation de dominance floue. Comme résultat, les services Web présentant un meilleur compromis entre les paramètres QoS sont retenus, alors que les services Web ayant un mauvais compromis entre les QoS sont exclus. Finalement, nous avons aussi absorbé le cas où les QoS décrivant les services Web sont entachés d’incertitude. La théorie des possibilités est utilisée comme modèle de l’incertain. Ainsi, un Skyline de Services possibilité est proposé pour permettre à l’utilisateur de sélectionner les services Web désirés en présence de QoS incertains. De riches expérimentations ont été conduites afin d’évaluer et de valider toutes les approches proposées dans cette thèse / As we move from a Web of data to a Web of services, enhancing the capabilities of the current Web search engines with effective and efficient techniques for Web services retrieval and selection becomes an important issue. In this dissertation, we present a framework that identifies the top-k Web service compositions according to the user fuzzy preferences based on a fuzzification of the Pareto dominance relationship. We also provide a method to improve the diversity of the top-k compositions. An efficient algorithm is proposed for each method. We evaluate our approach through a set of thorough experiments. After that, we consider the problem of Web service selection under multiple users preferences. We introduce a novel concept called majority service skyline for this problem based on the majority rule. This allows users to make a “democratic” decision on which Web services are the most appropriate. We develop a suitable algorithm for computing the majority service skyline. We conduct a set of thorough experiments to evaluate the effectiveness of the majority service skyline and the efficiency of our algorithm. We then propose the notion of α-dominant service skyline based on a fuzzification of Pareto dominance relationship, which allows the inclusion of Web services with a good compromise between QoS parameters, and the exclusion ofWeb services with a bad compromise between QoS parameters. We develop an efficient algorithm based on R-Tree index structure for computing efficiently the α-dominant service skyline. We evaluate the effectiveness of the α-dominant service skyline and the efficiency of the algorithm through a set of experiments. Finally, we consider the uncertainty of the QoS delivered by Web services. We model each uncertain QoS attribute using a possibility distribution, and we introduce the notion of pos-dominant service skyline and the notion of nec-dominant service skyline that facilitates users to select their desired Web services with the presence of uncertainty in their QoS. We then developappropriate algorithms to efficiently compute both the pos-dominant service skyline and nec-dominant service skyline. We conduct extensive sets of experiments to evaluate the proposed service skyline extensions and algorithms
203

Efeito da exclusão experimental de vertebrados na decomposição de três tipos de plantas sob diferentes coberturas de solo no parque estadual da serra do mar - núcleo Santa Virgínia / Evaluation of the experimental exclusion of vertebrates on the decomposition of three species of plants under different land uses in the state park serra do mar- nucleus Santa Virgínia

Medeiros, Gabriela Garcia 11 July 2016 (has links)
A diversidade da Mata Atlântica está constantemente ameaçada devido à perda de habitats provocada pela destruição e alteração dos ambientes naturais. Este fato é muito preocupante, pois os remanescentes florestais da Mata Atlântica encontram-se, em sua maior parte, em pequenos fragmentos altamente perturbados, acarretando em perda de biodiversidade da fauna existente. Muitos estudos demonstraram que mamíferos e aves especialistas (e. g. insetívoros) são muito sensíveis à fragmentação ambiental, tendendo a desaparecer em áreas abertas. A perda destes animais pode alterar a densidade de artrópodes e as taxas de herbivoria, ocasionando um efeito cascata (top- down), que causará influência até na decomposição e ciclagem de nutrientes. Entretanto o estudo de como esse efeito top-down ocorre em diferentes coberturas de solo ainda não foi testado, desta forma, objetivou-se investigar como as taxas de decomposição são modificadas pela exclusão experimental de vertebrados em áreas com diferentes coberturas vegetais na mata Atlântica. Parcelas de exclusão de vertebrados e parcelas controle foram alocadas em áreas com coberturas vegetais de pastagem e floresta, para verificar como ocorre o efeito top-down na decomposição. Utilizaram-se três tipos de serapilheira diferentes, uma gramínea (Brachiaria decumbens), uma espécie pioneira (Tibouchina sellowiana) e uma mistura de folhas de diferentes espécies da floresta primária adjacente. A técnica dos litter bags foi utilizada para avaliar as diferentes taxas de decomposição e foram coletados em intervalos de 16, 36, 71, 181 e 247 dias. O resíduo vegetal foi limpo, seco e pesado para obtenção das massas remanescentes (%) e taxa de decomposição, após isso o material foi triturado e pesado em subamostras para analises de nutrientes e compostos orgânicos (nitrogênio, carbono, fósforo, lignina, celulose e polifenóis). A taxa de decomposição não diferiu entre os tratamentos controle e exclusão de vertebrados, desta forma, não foi possível observar o efeito top-down da exclusão de vertebrados neste estudo, provavelmente devido à elevada biodiversidade da fauna do solo na área onde o experimento foi realizado e sugere-se repeti-lo em uma área menor e mais desconectada, com a finalidade de simular como o efeito cascata ocorre em pequenos fragmentos da mata Atlântica. Além disso, a decomposição foi mais rápida nos litter bags localizados na floresta do que na pastagem e as folhas de gramínea tiveram maior perda de massa do que as folhas de floresta primária e T. sellowiana, possivelmente devido às interações entre nitrogênio, lignina e a relação C:N dos resíduos vegetais. / The diversity of Atlantic forest is constantly threatened due to habitat loss caused by the destruction and alteration of natural environments, and most of the biome is now in small and fragmented areas. This fact is of a great concern, because the remaining areas in Atlantic forest are in small highly disturbed fragments, resulting in loss of biodiversity of the existing fauna, like mammals and birds. Many studies have shown that specialist mammals and birds (e.g. insectivores) are very sensitive to environment fragmentation and tend to disappear in open areas. The loss of these animals is likely to cause an increase in the density of arthropods and rates of herbivory, causing a top-down effect that may even influence the cycling of nutrients. We aimed to investigate how decomposition rates are modified by the experimental exclusion of vertebrates in an area with different land coverage in the Atlantic forest. Vertebrate exclusion plots and control plots were allocated in areas with different land coverage (pasture and forest) to evaluate the top-down effects in decomposition. We used three different kinds of leaves, being one grass (Brachiaria decumbens), one very common primary specie of the area (Tibouchina sellowiana) and a mix of primary forest leaves. Litterbags were used to evaluate the decomposition rate and it was collected during intervals of 16, 36, 71, 181 and 247 days. The vegetal residue was cleaned, dried and weighted to obtain the remaining mass (%) and decomposition rate, after that, the material was milled and weighted in subsamples for analyses of nutritional quality (N, C, P, lignin, cellulose and polyphenols). The decomposition rate was not different for the control and vertebrate exclusion plots, as a result, it was not possible to show the top-down effect in decomposition, possibly because of the high soil biodiversity in the area where the experiment was done. It would be very important to remake this experiment in a smaller and more disconnected area, in order to show how this cascade effect occur in Atlantic forest´s smaller fragments. Furthermore, the decomposition was faster at the forest plots than at the pastureland plots and the grass leaf litter presented the higher decomposition rate than the primary forest leaves and T. sellowiana and it was possibly caused by the interaction between nitrogen, lignin and C:N ratio.
204

Lectinas da esponja marinha Haliclona (Soestella) caerulea / Lectins from the marine sponge Haliclona (Soestella) caerulea

RÃmulo Farias Carneiro 16 August 2013 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Lectinas podem ser definidas como proteÃnas/glicoporteÃnas que reconhecem carboidratos de maneira especÃfica, mas nÃo participam do metabolismo dos mesmos e nÃo pertencem a nenhuma das principais classes de imunoglobulinas. As lectinas sÃo proteÃnas ubÃquas, estando presente em todos os organismos conhecidos. Em cÃlulas animais, lectinas tÃm sido encontradas no citoplasma, no nÃcleo e associadas a membranas das mais diversas organelas e nos mais variados tipos celulares. Tais lectinas animais podem ser classificadas em famÃlias distintas com base em suas caracterÃsticas fÃsico quÃmicas, funÃÃo e especialmente em sua identidade de estrutura primÃria e terciÃria. O objetivo deste trabalho foi purificar duas novas lectinas da esponja marinha Haliclona (Soestella) caerulea e caracterizar estruturalmente uma delas. EspÃcimes de H.caerulea foram coletados na praia do paracuru, CearÃ. Duas lectinas (H-1 e H-3) foram isoladas por tÃcnicas clÃssicas de quÃmica de proteÃnas. A estrutura primÃria de uma delas foi determinada por espectrometria de massas e RACE. A atividade tÃxica das lectinas foi avaliada frente à nÃuplios de Artemia e cepas das bactÃrias Escherichia coli e Staphylococus aureus. H-1 e H-3 apresentaram caracterÃsticas distinhas da lectina previamente isolada de H. caerulea. H-1 à uma proteÃna monomÃrica de aporoximadamente 40 kDa enquanto que H-3 à uma proteÃna trimÃrica com cadeias com massa aproximada de 9, 16 e 18 kDa. H-3 aglutina eritrÃcitos humanos do tipo A e B e foi inibida GalNAc e PSM, H-1 aglutina diversos grupos sanguineos e nÃo pÃde ser inibida por nenhum aÃÃcar testado. H-1 foi tÃxica a naÃplios de Artemia (LC50=6,4 μg.mL-1) e H-3 foi considerada nÃo tÃxica (LC50=414,2 μg.mL-1). H-3 à uma proteÃna azul, pois interage com um cromÃforo de 597 Da com absorÃÃo mÃxima a 620 nm. A estrutura primÃria de H-3 foi determinada e revelou-se Ãnica, nÃo sendo conhecida nenhuma lectina com estrutura similar. H-3 apresenta um glicano hÃbrido composto por Hex7NAcHex7DeoxiHex2. A cadeia α de H-3 sofre um processamento proteolÃtico complexo que ainda nÃo foi completamente elucidado. AlÃm disso, H-3 foi cristalizada, mas nÃo foi possÃvel a obtenÃÃo de um padraÃo de difraÃÃo que permita a resoluÃÃo da estrutura. Em suma, duas novas lectinas foram isoladas e fora observado pela primeira vez a interaÃÃo entre uma lectina e um cromÃforo natural. Pela primeira vez tambÃm, fora determinada a composiÃÃo glicÃdica de uma lectina de esponja. / Lectins are proteins/glycoproteins that recognize carbohydrate of a specific way, but not participate in the metabolism of the same and do not belong to any of major classes of immunoglobulins. Lectins are ubiquitous proteins, present in all known organisms. In animal cells, lectins have been found in the cytoplasm, in the nucleous and as membrane-associated proteins, in diverse organelles and cells. Animal lectins can be classified into distinct families based on their physicochemical characteristics, especially in their function and identity of primary and tertiary structure. The aim of this study was to purify, characterize structural and biologically new lectins from the marine sponge Haliclona (Soestella) caerulea. H. caerulea specimens were collected in Paracuru beach, CearÃ. Two lectins (H-1 and H-3) were isolated by classical techniques of protein chemistry. The primary structure of H-3 was determined by mass spectrometry and RACE. The toxic activity of lectins was evaluated against Artemia nauplii and Escherichia coli and Staphylococcus aureus strains. H-1 and H-3 showed distinct characteristics of the lectin previously isolated from H. caerulea. H-1 is a monomeric protein of 40 kDa whereas H-3 is a heterogeneus protein with chains of 9, 16 and 18 kDa. H-3 binds human erythrocytes of A and B type and was inhibited by GalNAc and PSM, H-1 binds different blood groups and could not be inhibited by any sugar tested. H-1 was toxic to Artemia nauplii (LC50 = 6.4 μg.mL-1) and H-3 was not considered toxic (LC50 = 414.2 μg.mL-1). H-3 is a blue protein that interacts with a chromophore of 597 Da of maximum absorbance at 620 nm. The primary structure of H-3 revealed a unique amino acid sequence no similar to any animal lectins known. H-3 has a hybrid glycan comprising by Hex7NAcHex7DeoxiHex2. The α-chain of H-3 undergoes complex proteolytic processing that not been fully elucidated. Moreover, H-3 was crystallized, but was not possible to obtain a diffraction pattern that permits solving the structure. In short, two new lectins were isolated and out first observed the interaction between a lectin and natural chromophore. Furthermore, for the first time given the composition glicidic out of a sponge lectin.
205

Efeito da exclusão experimental de vertebrados na decomposição de três tipos de plantas sob diferentes coberturas de solo no parque estadual da serra do mar - núcleo Santa Virgínia / Evaluation of the experimental exclusion of vertebrates on the decomposition of three species of plants under different land uses in the state park serra do mar- nucleus Santa Virgínia

Gabriela Garcia Medeiros 11 July 2016 (has links)
A diversidade da Mata Atlântica está constantemente ameaçada devido à perda de habitats provocada pela destruição e alteração dos ambientes naturais. Este fato é muito preocupante, pois os remanescentes florestais da Mata Atlântica encontram-se, em sua maior parte, em pequenos fragmentos altamente perturbados, acarretando em perda de biodiversidade da fauna existente. Muitos estudos demonstraram que mamíferos e aves especialistas (e. g. insetívoros) são muito sensíveis à fragmentação ambiental, tendendo a desaparecer em áreas abertas. A perda destes animais pode alterar a densidade de artrópodes e as taxas de herbivoria, ocasionando um efeito cascata (top- down), que causará influência até na decomposição e ciclagem de nutrientes. Entretanto o estudo de como esse efeito top-down ocorre em diferentes coberturas de solo ainda não foi testado, desta forma, objetivou-se investigar como as taxas de decomposição são modificadas pela exclusão experimental de vertebrados em áreas com diferentes coberturas vegetais na mata Atlântica. Parcelas de exclusão de vertebrados e parcelas controle foram alocadas em áreas com coberturas vegetais de pastagem e floresta, para verificar como ocorre o efeito top-down na decomposição. Utilizaram-se três tipos de serapilheira diferentes, uma gramínea (Brachiaria decumbens), uma espécie pioneira (Tibouchina sellowiana) e uma mistura de folhas de diferentes espécies da floresta primária adjacente. A técnica dos litter bags foi utilizada para avaliar as diferentes taxas de decomposição e foram coletados em intervalos de 16, 36, 71, 181 e 247 dias. O resíduo vegetal foi limpo, seco e pesado para obtenção das massas remanescentes (%) e taxa de decomposição, após isso o material foi triturado e pesado em subamostras para analises de nutrientes e compostos orgânicos (nitrogênio, carbono, fósforo, lignina, celulose e polifenóis). A taxa de decomposição não diferiu entre os tratamentos controle e exclusão de vertebrados, desta forma, não foi possível observar o efeito top-down da exclusão de vertebrados neste estudo, provavelmente devido à elevada biodiversidade da fauna do solo na área onde o experimento foi realizado e sugere-se repeti-lo em uma área menor e mais desconectada, com a finalidade de simular como o efeito cascata ocorre em pequenos fragmentos da mata Atlântica. Além disso, a decomposição foi mais rápida nos litter bags localizados na floresta do que na pastagem e as folhas de gramínea tiveram maior perda de massa do que as folhas de floresta primária e T. sellowiana, possivelmente devido às interações entre nitrogênio, lignina e a relação C:N dos resíduos vegetais. / The diversity of Atlantic forest is constantly threatened due to habitat loss caused by the destruction and alteration of natural environments, and most of the biome is now in small and fragmented areas. This fact is of a great concern, because the remaining areas in Atlantic forest are in small highly disturbed fragments, resulting in loss of biodiversity of the existing fauna, like mammals and birds. Many studies have shown that specialist mammals and birds (e.g. insectivores) are very sensitive to environment fragmentation and tend to disappear in open areas. The loss of these animals is likely to cause an increase in the density of arthropods and rates of herbivory, causing a top-down effect that may even influence the cycling of nutrients. We aimed to investigate how decomposition rates are modified by the experimental exclusion of vertebrates in an area with different land coverage in the Atlantic forest. Vertebrate exclusion plots and control plots were allocated in areas with different land coverage (pasture and forest) to evaluate the top-down effects in decomposition. We used three different kinds of leaves, being one grass (Brachiaria decumbens), one very common primary specie of the area (Tibouchina sellowiana) and a mix of primary forest leaves. Litterbags were used to evaluate the decomposition rate and it was collected during intervals of 16, 36, 71, 181 and 247 days. The vegetal residue was cleaned, dried and weighted to obtain the remaining mass (%) and decomposition rate, after that, the material was milled and weighted in subsamples for analyses of nutritional quality (N, C, P, lignin, cellulose and polyphenols). The decomposition rate was not different for the control and vertebrate exclusion plots, as a result, it was not possible to show the top-down effect in decomposition, possibly because of the high soil biodiversity in the area where the experiment was done. It would be very important to remake this experiment in a smaller and more disconnected area, in order to show how this cascade effect occur in Atlantic forest´s smaller fragments. Furthermore, the decomposition was faster at the forest plots than at the pastureland plots and the grass leaf litter presented the higher decomposition rate than the primary forest leaves and T. sellowiana and it was possibly caused by the interaction between nitrogen, lignin and C:N ratio.
206

Qualidade em Servi?os: Um estudo de caso de micro e pequenas empresas prestadoras de servi?os do Estado do Rio de Janeiro finalistas no Pr?mio Top Empresarial. / Service Quality: A case study of micro and small companies that render its services for the government of the state of Rio de Janeiro and are finalists in Pr?mio Top Empresarial.

Moura, Jaqueline Mateus de 19 April 2006 (has links)
Made available in DSpace on 2016-04-28T20:19:14Z (GMT). No. of bitstreams: 1 2006-Jaqueline Mateus de Moura.pdf: 869956 bytes, checksum: 2984fe7f264612506c928a589208cf7e (MD5) Previous issue date: 2006-04-19 / The search for the survival and organizational competitiveness through the innovation, adaptation and new formulation of the administration model, for the organizations in the current global scenery, is the object of this study: the management for applied excellence to the services sector. This economical segment, that it is in constant growth and development, is a great generator of job and income. To render quality services becomes a competitiveness differential, mainly, for micro and small companies. For analysis of the management maturity of this sector a study case was used considering companies involved in the Top Business Award of the Rio de Janeiro State, whose main objective is to induce the micro and small companies build a new innovative and auto-maintainable organizational structure. Based on socioeconomic data and statisticians on the growth of the services sector, the increasing of the micro and small companies in the national economy and documents on the Top Business Award, the research sought to contemplate the general objective that it is to answer the following subject: Are the micro and small companies prepared and/or informed about what is really an administration model for excellence ? So, it was analyzed the answer of questionnaires and the, respective, punctuation of the micro and small finalists companies of the services category of the Top Business Award in the period from 2003 to 2005. The results of this research appear for a medium variation of points, where some criteria were considerably below the necessary maximum punctuation demanded by the award. When confronting the presented concepts in the theoretical referential and the analysis of the study, the conclusion was that the companies participant need specific training for a better understanding and development of concepts related to the improvement of its management, to become and maintain themselves competitive. / A busca pela sobreviv?ncia e competitividade organizacional atrav?s da inova??o, adapta??o e reformula??o do modelo de gest?o, pelas organiza??es no cen?rio atual, globalizado, ? o objeto deste estudo: a gest?o para excel?ncia aplicada ao setor de servi?os. Este segmento econ?mico, que est? em constante crescimento e desenvolvimento ? um grande gerador de emprego e renda. Prestar servi?os de qualidade torna-se um diferencial competitivo, principalmente, para micro e pequenas empresas. Para an?lise da maturidade da gest?o deste setor foi utilizado um estudo de caso compreendendo empresas envolvidas no Pr?mio Top Empresarial do Estado do Rio de Janeiro, cujo principal objetivo ? induzir ?s micro e pequenas empresas a constru?rem uma nova estrutura organizacional inovadora e autosustent?vel. Com base em dados s?cio-econ?micos e estat?sticos sobre o crescimento do setor de servi?os, o aumento de micro e pequenas empresas na economia nacional e documentos sobre o Pr?mio Top Empresarial a pesquisa procurou contemplar o objetivo geral que ? responder a seguinte quest?o: ser? que micro e pequenas empresas est?o preparados e/ou informadas sobre o que ? realmente um modelo de gest?o para excel?ncia? Para isso, foi analisada a resposta de question?rios e a, respectiva, pontua??o de micro e pequenas empresas finalistas da categoria servi?os do Pr?mio Top Empresarial no per?odo de 2003 a 2005. Os resultados deste trabalho apontam para uma varia??o m?dia de pontos, em que alguns crit?rios ficaram bem abaixo da pontua??o m?xima necess?ria exigida pelo pr?mio. Ao confrontar os conceitos apresentados no referencial te?rico e a an?lise do estudo, conclui-se que as empresas participantes necessitam de capacita??o espec?fica para um melhor entendimento e desenvolvimento de conceitos relacionados ? melhoria de sua gest?o, para tornarem-se e manterem-se competitivas.
207

A search for massive resonances decaying to top quark pairs and jet trigger performance studies with the ATLAS detector at the Large Hadron Collider

Fajardo, Luz Stella Gomez 17 July 2014 (has links)
Diese Arbeit behandelt die Suche nach neuen Teilchen, die in Top-Quark-Paare zerfallen (t¯t). Die Analyse beruht auf Daten des ATLAS-Experiments von Proton- Proton-Kollisionen am LHC bei einer Schwerpunktsenergie von p s = 7 TeV und einer Gesamtluminosität von 2.05 fb−1. Hierzu wird der Lepton+Jets Endzustand im t¯t ! WbWb Zerfallskanal verwendet, worin ein W-Boson leptonisch und das andere hadronisch zerfällt. Das t¯t -Ereignis wird sowohl in aufgelösten als auch geboosteten Zerfallstopologien rekonstruiert. Zum ersten Mal werden die Korrelationen beider Kanäle in Form einer dritten Kategorie nutzbar gemacht, welche aus Ereignissen besteht, die in beiden Topologien selektiert wurden. Die Sensitivität der Analyse wird hierdurch erhöht. Obere Schranken bei 95% Vertrauensniveau auf den Wirkungsquerschnitt multipliziert mit der Zerfallsbreite für massive Zustände großer und kleiner Zerfallsbreite werden berechnet. Diese werden aus der Kombination der beiden Ansätze der t¯t -Rekonstruktion gewonnen. Für die Z0-Resonanz kleiner Breite reicht die beobachtete (erwartete) obere Grenze auf den Wirkungsquerschnitt von 4.85 (4.81) pb, für eine Masse von 0.6 TeV, bis 0.21 (0.13) pb, für eine Masse von 2 TeV. Eine schmale leptophobische Topcolor-Z0-Resonanzen mit einer Masse unterhalb von 1.3 TeV kann ausgeschlossen werden. Weiterhin konnten beobachtete (erwartete) obere Grenzen auch für eine breite Farboktett-Resonanz berechnet werden. Diese liegen zwischen 2.52 (2.59) pb und 0.37 (0.27) pb für Massen von 0.7 TeV bzw. 2 TeV. Breite Kaluza-Klein-Gluon-Resonanzen mit einer Masse unter 1.65 TeV können ausgeschlossen werden. / This thesis presents the search for new particles that decay into top quark pairs (t¯t). The analysis is performed with the ATLAS experiment at the LHC, using an integrated luminosity of 2.05 fb−1 of proton–proton collision data, collected at a center-of-mass energy of p s = 7 TeV. The lepton plus jets final state is used in the t¯t ! WbWb decay, where one W boson decays leptonically and the other hadronically. The t¯t system is reconstructed using both resolved and boosted topologies of the top-quark decay. For the first time, correlations between the two search channels have been employed by creating a third channel with the events selected by both analyses. The sensitivity to new physics phenomena is thereby improved. Upper limits are derived on the production cross-section times branching ratio for narrow and wide massive states, at the 95 % confidence level. These are extracted by combining the two approaches of the t¯t reconstruction. For a narrow Z0 resonance, the observed (expected) upper limits range from 4.85 (4.81) pb for a mass of 0.6 TeV, to 0.21 (0.13) pb for a mass of 2 TeV. A narrow leptophobic topcolor Z0 resonance with a mass below 1.3 TeV is excluded. Observed (expected) limits are also derived for a broad color-octet resonance. They vary between 2.52 (2.59) pb and 0.37 (0.27) pb for a mass of 0.7 TeV and 2 TeV, respectively. The wide Kaluza-Klein gluon with a mass below 1.65 TeV is excluded. Another aspect of this thesis are performance studies of the level-1 jet trigger. Trigger efficiencies have been measured, using data collected by the ATLAS detector in 2010 at p s = 7 TeV. The turn-on curves obtained for a variety of jet triggers, showed good agreement between data and simulation in the plateau region. The efficiency results were used at the first stage of analyses for multi-jet cross-section measurements.
208

Perspectives de mesure de la masse du quark Top avec le detecteur ATLAS

Roy, Pierrick 01 January 2002 (has links) (PDF)
Ce document présente le travail réalisé pour instrumenter les "Super-Timim", supports de l'électronique frontale du calorimètre hadronique à tuiles scintillantes d'ATLAS, ainsi que l'analyse préparatoire de mesure de la masse du quark Top avec le détecteur ATLAS. Dans un premier temps, la partie instrumentale expose les différentes étapes ayant conduit â l'instrumentation. Ceci a nécessité en amont une phase dite d'intégration, lors de laquelle des méthodes ont été développées pour résoudre les problèmes liés aux contraintes d'espace et à l'ergonomie lors de l'assemblage des Super-Tiroirs. L'expérience acquise lors de cette première phase a permis la rédaction du protocole de montage des Super-Tiroirs et la mise en place des deux chaînes de montage. Les dix premiers Super-Tiroirs ont ainsi été produits pour ha période de faisceaux 2001, et le démarrage de la production en continu des 260 Super-Tiroirs restants doit commencer en juin 2002. Dans la partie analyse, cette thèse traite de la mesure précise de la masse du quark Top dans le canal lepton plus jets. Il est montré en premier lieu que les incertitudes systématiques domineront la précision de la mesure, en particulier la connaissance de l'échelle d'énergie des jets ainsi que les rayonnements de gluons dans l'état final, conduisant à une erreur totale d'environ 2 GeV. Il est ensuite montré que les mêmes événements peuvent être utilisés pour l'étalonnage en énergie des jets légers à mieux que le pour-cent. Enfin l'utilisation d'un ajustement cinématique devrait permettre de réduire l'impact des effets dus à la connaissance de l'échelle d'énergie des jets légers ainsi qu'aux rayonnements dans l'état final. Une incertitude totale sur la mesure de la masse du quark Top à mieux que 1 GeV paraît envisageable en une année de prise de données à basse luminosité, cette incertitude étant dominée par la connaissance de l'échelle d'énergie des jets de quarks b, supposée à 1%.
209

Etudes dans le canal avec deux leptons de même signe de la physique du top au-delà du modèle standard

Gauthier, Léa 14 September 2012 (has links) (PDF)
Le sujet de cette thèse est " L'étude dans le canal avec deux leptons de même signe de la physique du top au-delà du Modèle Standard avec le détecteur ATLAS au LHC et l'étude du niveau de déclenchement L1 du calorimètre ". Cette thèse porte sur la recherche de processus de nouvelle physique au LHC faisant jouer au quark top un rôle particulier. Le LHC est un collisionneur de protons, conçu pour un fonctionnement nominal avec une énergie dans le centre de masse de 14 TeV. Jusqu'à fin 2011 il a fonctionné avec une énergie de 7 TeV dans le centre de masse. Les premières données recueillies (5 fb−1 à 7 TeV) nous ont permis de contraindre certains paramètres de la nouvelle physique recherchée. C'est dans ce cadre que s'inscrit cette thèse. Celle-ci est divisée en trois parties. La première décrit rapidement l'accélérateur avant de s'intéresser à l'expérience ATLAS et au fonctionnement de son détecteur. Le bon fonctionnement des cartes de sommation du signal du calorimètre électromagnétique pour le premier niveau de déclenchement des événements a été tout particulièrement étudié. La deuxième partie est une analyse phénoménologique de la physique au-delà du Modèle Standard avec quatre quarks top dans l'état final pour plusieurs modèles théoriques. Cette étude a été effectuée principalement au niveau générateur pour 14 TeV dans le centre de masse mais nous commentons également les perspectives à 7 TeV. Elle peut être appliquée à l'expérience ATLAS comme à l'expérience CMS. La troisième partie est une étude expérimentale, réalisée avec le détecteur ATLAS, recherchant des manifestations d'un modèle de Higgs composite prédisant l'existence de partenaires exotiques au quark top (T5/3) et d'un modèle de théorie effective de production des 4 tops. Une limite sur la masse du partenaire exotique a été obtenue ainsi qu'une limite sur la section efficace des événements exotiques à quatre tops.
210

Från top down till bottom up : - Att förklara och utvärdera psykosocialt arbete inom hälso- och sjukvården

Landpers, Håkan January 2010 (has links)
Today, activities funded with public funds needs to present relevant and reliable information which shows the results obtained. Requirements increase in welfare activities to be run based on scientific, empirical knowledge. This applies particularly to social work. The social work is, however, poorly researched in areas such as knowledge of interventions in the content, context and effects. One way to evidence-base social work can be to conduct regular and qualified assessments. To evaluate, however, is complex, and knowledge of the evaluations are deficient in those who plan and execute them. The overall aim of this study was to conduct a systematic literature review to identify key evaluation models to the psychosocial work in health care services. A further aim was to develop an evaluation design for the psychosocial work of kuratorsenheten, Falun Hospital. The evaluation models are presented in the paper based on categories of “top down” and “bottom up ", and" other models ". With the help of some key concepts for the evaluation of social work, the conclusion of the meta-theory of critical realism, conducted the study analysis. The results show that the models relevant to the evaluation of psychosocial work in the health services are mainly oriented towards a bottom up perspective. The models are process evaluations, user-oriented models, stakeholder assessments, self assessments, and goals - performance evaluations. The evaluation design of kuratorsenheten also presents a number of elements in the psychosocial work which is central to document, for the opportunity to explain, evaluate and develop the business forward.

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