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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.
561

Contribution à l’étude des questions statistiques rencontrées dans l’analyse des données de cohorte de personnes vivant avec le VIH sous traitement antirétroviral dans un contexte de ressources limitées / Contribution to the study of statistical issues encountered in the analysis cohort of people living with HIV receiving antiretroviral therapy in resource-limited settings

Beaudrap, Pierre De 14 December 2009 (has links)
L’épidémie du VIH/SIDA a particulièrement touché l’Afrique Sub-Saharienne. En 1998, le gouvernement sénégalais a mis en place une cohorte observationnelle d’adultes infectés par le VIH-1 afin d’évaluer l’impact des antirétroviraux donnés au sein de l’Initiative Sénégalaise d’Accès aux Antirétroviraux (ISAARV). Plus spécifiquement, cette évaluation portait sur l’efficacité clinique et biologique des traitements, leur tolérance clinique et biologique, l’observance et l’émergence de résistances virales. La cohorte ANRS 1215 a été mise en place entre 1998 et 2002 à partir des 404 premiers patients inclus dans l’ISAARV. Cette thèse a utilisé les données recueillies au sein de cette cohorte pour analyser certains aspects de la réponse bio-cliniques aux traitements antirétroviraux en Afrique. Dans la première partie de ce travail, différents aspects de l’infection par le VIH en Afrique Sub-Saharienne et les questions relatives à la réponse bio-cliniques aux traitements antirétroviraux ont été passés en revus. Dans la seconde partie, les aspects méthodologiques de l’analyse des données longitudinales de cohorte ainsi que les problématiques associées ont été étudiés. Enfin, différents aspects de la réponse bio-cliniques après initiation des antirétroviraux ont été analysés au travers de 5 articles portant sur la mortalité précoce, la reconstitution immunologique, la survenue d’évènements classant, la réponse et la tolérance à deux régimes thérapeutiques différents. / Sub-Saharan Africa has been heavily affected by the HIV/AIDS epidemic. In 1998, the Sengalese government launched an observational cohort of HIV-1 infected adults that aimed to assess the impact of antiretroviral therapy (ART) provided by the “l’Initiative Sénégalaise d’Accès aux Antirétroviraux” (ISAARV). This assessment focused more specifically on the clinical and biological effectiveness of ART, on the clinical and biological tolerance and on the emergence of virological resistances. The cohort was made of the first 404 patients included in the ISAARV between 1998 and 2002. The data collected through this cohort have been used to analyse in this work various aspects of biological and clinical answer to ART in Africa. In the first section, different aspects of the HIV/AIDS infection in Sub-Saharan countries have been reviewed with an emphasis put on the remaining bio-clinical questions. In the second, methodological aspects of the analysis of longitudinal data and related questions have been studied. Then, various aspects of the biological and clinical answer to ART have been analysed through five articles about early mortality, immune reconstitution, AIDS-defining illness occurrence, and the effectiveness and tolerance of two regimen.
562

Analýha a komparace inflace v ČR a SRN / Inflation analysis and its comparison in the Czech Republic and Germany

Maxa, Jan January 2012 (has links)
The aim of this paper is to analyse and compare inflation and its dynamics between two countries -- the Czech Republic and Germany -- applying a special kind of econometric models. The first part of this paper is dedicated to economic theory of inflation -- fundamental terms, measuring methods and its targeting. The monetary policy in the Czech Republic and Germany is also shortly introduced. Next chapter tries to describe the econometric concept which is used in this paper -- vector autoregression model (VAR model). In connection with the VAR models, Granger causality, impulse response function, cointegration and error correction model are mentioned as well. The empirical part includes application of selected models on real time series of macroeconomic indicators. Next to the interpretation of results, the forecasts are also implemented.
563

Rakouská teorie hospodářského cyklu: empirická evidence pro dlouhé období / The Austrian business cycle theory: empirical evidence

Komrska, Martin January 2012 (has links)
The aim of this diploma thesis is to empirically investigate the explanatory power of Austrian business cycle theory. My dataset consists of US quarterly time series within the period between 1971 and 2009. As regards the NBER classification, this dataset covers six complete business cycles, including the recent global financial crisis. Following Wainhouse (1984), Keeler (2001) and Bjerkenes et al. (2010) I use Granger causality as one of the primary tools of the analysis. Moreover I also add Impulse response functions to discover the direction of observed relationships. As regards my primary group of hypotheses I found significant empirical evidence for the connection between changes in interest rate and structure of production. The secondary group of hypotheses is less successful; however I found the very first empirical illustration of Garrison's version of ABCT.
564

Zahraniční investice a růst regionů České republiky v letech 1998 - 2011 / Foreign Investment and growth of the regions of the Czech Republic in 1998 - 2011

Říhová, Gabriela January 2009 (has links)
The dissertation analyzes the impact of Foreign Direct Investment (FDI) on Economic Growth by extension and economic development of the regions of the Czech Republic (CZ) in 1998 -- 2011. Statistical data empirically study determined motivation of investors to locate in economically strong regions. Following the analysis of statistical data, available resources and a field survey, whose output includes three case studies of specific Foreign Investments in the Czech Republic, the analysis examines whether the arrival of a significant foreign direct investor in the region significantly influenced selected characteristics of economic performance, or other selected areas in region (social, environmental, transport etc.). Moreover, in the context of econometric analysis to test the tightness of the relationship between Foreign Direct Investment and Economic Growth using Pearson's coefficient and characteristics of variability. The causal effect of Foreign Direct Investment on Economic Growth (and vice versa) is analyzed using Granger causality test. The conclusion gives an assessment of the significance of Foreign Direct Investment in the regions of the Czech Republic together with the identification of significant effects brought by investments.
565

Tópicos em dinâmica de fluidos como uma teoria de campo / Topics in fluid dynamics as field theory

Coelho, David Montenegro, 1990- 31 August 2018 (has links)
Orientador: Donato Giorgio Torrieri / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-31T06:57:06Z (GMT). No. of bitstreams: 1 Coelho_DavidMontenegro_M.pdf: 2238497 bytes, checksum: 78f745f9d544a31d97a2d7a80b7dc505 (MD5) Previous issue date: 2016 / Resumo: O interesse científico cresceu após confirmado por testes experimentais o comportamento do Plasma de Quark-Glúon como um fluido quase perfeito no LHC e RHIC. O objetivo desse trabalho é fornecer as bases teóricas da Effective Field Theory (EFT) na abordagem da Hidrodinâmica, pois vários recursos não-triviais na dinâmica relativística dos fluidos são claramente explicados por esse formalismo. Problemas teóricos na EFT sugerem a inclusão de uma nova formulação do Princípio de Hamilton compatível com o princípio da causalidade, através do Closed-Time-Path. Após resolvido esse problema, alcançamos o requisito necessário para derivar a hidrodinâmica dissipativa em altas ordens por meio da ação. Assim, conseguimos caracterizar a Lagrangeana de Navier-Stokes ao introduzir a quebra de simetria na preservação do difeomorfismo pelo volume por meio do termo $B^{-1}_{IJ}$. No entanto, uma análise pelo método de Ostrogradski levou à supressão dessa equação, através da inclusão da Lagrangeana de Israel-Stewart na expansão que é justificada por meios de argumentos de estabilidade e causalidade. Por fim, propomos uma variável $X_{IJ}$ na Lagrangeana de Israel-Stewart, simétrica, anisotrópica e dependente das condições iniciais que juntamente com os já estabelecidos graus de liberdade de campo, formam a base para a derivação bottom-up em altas ordens da EFT e propicia medidas para estudar turbulência e instabilidade no vácuo e outras situações que chegam da relação entre graus de liberdade macroscópico e microscópico / Abstract: Scientific interest grew after the behavior of the quark-gluon Plasma as a nearly perfect fluid in the LHC and RHIC. The objective of this dissertation is offer support to use the Effective Field Theory (EFT) approach to study hydrodynamics because many non-trivial features in relativistic fluid dynamics are clearly explained by this Lagrangian formalism. Theoretical problems in EFT considering by including a new formulation of the Hamiltonian principle that is compatible with the principle of causality for non-conservative field through the Closed-Time-Path formalism. After solving this problem, we reached requirement to derive the dissipative hydrodynamics in higher orders of action. We were able to characterize Navier-Stokes' Lagrangian by introducing the symmetry breaking of preserving diffeomorphism through the volume with the term $B^{-1}_{IJ} $ to the Lagrangian of Navier-Stokes. An analyse of Ostrogradski's method led to the removal of equation by including the Israel-Stewart term in the Lagrangian expansion that provides an extra justification by means of symmetry and causality arguments. Finally, we propose a variable $ X_ {IJ} $, Israel-Stewart's Lagrangian, symmetric, anisotropic and dependent on initial conditions together with an established degree of freedom of the field, which form the basis for the derivation of higher orders of the bottom up and promote steps to the study of turbulence by instability in the vacuum, and other situations arising from the relationship between macroscopic and microscopic degrees of freedom / Mestrado / Física / Mestre em Física / 147435/2014-5 / CNPQ
566

Integration of heterogeneous data in time series : a study of the evolution of aquatic macrophytes in eutrophic reservoirs based on multispectral images and meteorological data /

Coladello, Leandro Fernandes. January 2020 (has links)
Orientador: Maria de Lourdes Bueno Trindade Galo / Resumo: O represamento de rios para a produção de energia elétrica usualmente provoca atividades antrópicas que impactam um ecossistema aquático fortemente. Uma das consequências de se instalar pequenos reservatórios em regiões sujeitas à intensos processos de urbanização e industrialização é a abundância de macrófitas, resultante do despejo de nutrientes em grandes concentrações no ecossistema aquático. Recentemente, o grande volume de images multitemporais de sensoriamento remoto disponíveis em bancos de dados gratuitos, bem como a alta performance computacional que permite a mineração de grandes volumes de dados, fazem com que o monitoramento de fenômenos ambientais seja um objeto de estudo recorrente. O propósito desse estudo é desenvolver uma metodologia baseada na integração de dados heterogêneos, fornecidos por séries temporais de coleções de imagens multiespectrais e multitemporais Landsat e coleções de dados climáticos históricos, para investigar a evolução e comportamento espacial de macrófitas aquáticas em lagos e reservatórios eutrofizados. A extensa coleção temporal de imagens de superfície de reflectância Landsat disponível e também dados de variáveis ambientais permitiram a construção e análise de séries temporais para investigar a recorrente abundância de macrófitas no reservatório de Salto Grande, localizado na região metropolitana de Campinas, São Paulo, Brasil. Inicialmente, foi encontrado que as imagens Landsat possuem a qualidade radiométrica necessária para se r... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: River damming for electric power production usually triggers anthropic activities that strongly impact on aquatic ecosystem. One of the consequences of installing small reservoirs in regions subject to an intense process of urbanization and industrialization is the overabundance of macrophytes, resulting from the input of nutrients in high concentration into the aquatic ecosystem. Currently, the large volume of multitemporal remote sensing images available in open data sources, as well as the high computational performance that allow the mining of large volumes of data has made the monitoring of environmental phenomena a recurrent object of analysis. The aim of this study is to develop a methodology based on the integration of heterogeneous data, provided by time series of multispectral and multitemporal Landsat images and collections of historical climatic data, to investigate the evolution and spatial behavior of aquatic macrophytes in lakes and eutrophic reservoirs. So, the extensive temporal collection of the Landsat surface reflectance images made available as well as environmental variables data permitted the construction and analysis of time series to investigate the recurrent over-abundance of macrophytes in Salto Grande reservoir, located in the metropolitan region of Campinas, São Paulo, Brazil. Initially, it was found that the the Landsat images have the necessary radiometric quality to perform the time series analyses, through an assessment based on information ab... (Complete abstract click electronic access below) / Doutor
567

The nexus between foreign direct investment and budget deficit in SADC Region

Hlongwane, Thabang Moses January 2020 (has links)
Thesis (M.Com. (Economics)) -- University of Limpopo, 2020 / The remarkable increase in FDI flows to developing countries over the last decade has focused attention on whether this source of financing enhances overall development and growth in the economy. To attain foreign direct investment and sustainable economic growth of a country, balanced budget is not only important but necessary. The aim of the study was to examine the nexus between foreign direct investment (FDI) inflows and budget deficit in a panel of five Southern African Development Community (SADC) countries (Malawi, South Africa, Tanzania, Namibia, and Zambia). The study employed the Panel Auto Regressive Distributed Lag (PARDL) model in examining the relationship between budget deficit and FDI. The panel unit root tests results showed different orders of integration (at levels and first-order) giving way to the use of PARDL. Co-integration test results confirmed a long-run relationship in the budget deficit FDI series. In the long run, there is a significant negative relationship between budget deficit and FDI. The speed of adjustment is 36%, implying that the system would converge faster to equilibrium. Furthermore, Granger causality test results indicated a bi-directional causal link on the interest rate – inflation and interest rate – FDI models. However, there is a unidirectional causality running from budget deficit to FDI; interest rate to the budget deficit and FDI to inflation. It is recommended that government should attract more foreign direct investment so as to minimise budget deficit and this could speed up the development of SADC countries. Key Terms: Foreign direct investment, budget deficit, Autoregressive-Distributed Lag, panel data, Granger causality.
568

Attenuation, Stasis, or Amplification: Change in the Causal Effect of Coercive Policies

Smith, Gregory Lyman January 2020 (has links)
No description available.
569

FORENSICS AND FORMALIZED PROTOCOL CUSTOMIZATION FOR ENHANCING NETWORKING SECURITY

Fei Wang (11523058) 22 November 2021 (has links)
<div>Comprehensive networking security is a goal to achieve for enterprise networks. In forensics, the traffic analysis, causality dependence in intricate program network flows is needed in flow-based attribution techniques. The provenance, the connection between stealthy advanced persistent threats (APTs) and the execution of loadable modules is stripped because loading a module does not guarantee an execution. The reports of common vulnerabilities and exposures (CVE) demonstrate that lots of vulnerabilities have been introduced in protocol engineering process, especially for the emerging Internet-of-Things (IoT) applications. A code generation framework targeting secure protocol implementations can substantially enhance security.</div><div>A novel automaton-based technique, NetCrop, to infer fine-grained program behavior by analyzing network traffic is proposed in this thesis. Based on network flow causality, it constructs automata that describe both the network behavior and the end-host behavior of a whole program to attribute individual packets to their belonging programs and fingerprint the high-level program behavior. A novel provenance-oriented library tracing system, Lprov, which enforces library tracing on top of existing syscall logging based provenance tracking approaches is investigated. With the dynamic library call stack, the provenance of implicit library function execution is revealed and correlated to system events, facilitating the locating and defense of malicious libraries. The thesis presents ProFactory, in which a protocol is modeled, checked and securely generated, averting common vulnerabilities residing in protocol implementations.</div>
570

Statistical inferences for missing data/causal inferences based on modified empirical likelihood

Sharghi, Sima 01 September 2021 (has links)
No description available.

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