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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.
281

Dinâmica espacial e contingências socioambientais da hanseníase no Estado do Maranhão: avaliação de riscos e vulnerabilidade em áreas hiperendêmicas / Spatial dynamics and socio and environmental contingencies of leprosy in Maranhão state: risk assessment and vulnerability in hyperendemic areas

Mauricio Eduardo Salgado Rangel 22 September 2016 (has links)
A hanseníase, doença crônica estigmatizante com potencial de causar danos neurológicos, resulta da infecção pelo Mycobacterium leprae. Análises epidemiológicas atuais têm utilizado ferramentas clínicas e de análise espacial para o mapeamento dos principais focos de ocorrência de doenças e de áreas de alto risco. Analisar os municípios maranhenses quanto à distribuição dos casos de hanseníase torna-se uma ferramenta a mais na prevenção e controle da Hanseníase no estado por inúmeros fatores: comporta-se como área hiperendêmica de hanseníase; apresenta fluxo migratório intenso com outras cidades de forma interestadual; e tem grandes contrastes sociais marcados por pouca, ou nenhuma, infraestrutura básica em algumas áreas dos vários municípios deste. Objetivos: Analisar a distribuição espaço-temporal da hanseníase para o estado do Maranhão, no período de 2001 a 2013. Identificar a ocorrência de agrupamentos espaços-temporais de provável alta transmissão (risco) e verificar se há associação dessa distribuição de taxas de detecção de risco relativo (RR) da doença com as variáveis do contexto geográfico como socioeconômicas e ambientais. Metodologia: A fonte de coleta dos dados clínicos e epidemiológicos foi o Sistema de Informação Nacional de Agravos Notificáveis do Ministério da Saúde e dos dados demográficos, ambientais e bases cartográficas digitais do Instituto Brasileiro de Geografia e Estatística. Foi adotada uma abordagem ecológica sobre tendências dos padrões espaçostemporais de transmissibilidade, com utilização dos métodos: varredura espacial (scan), para a identificação dos agregados (clusters) de risco, considerando o modelo de distribuição de probabilidade Discreto de Poisson; Estimador Bayesiano Empírico para a suavização local de taxas, a partir de informações de municípios vizinhos tendo como estratégia de construção o critério da contiguidade; regressão múltipla espacial considerando uma modelagem com distribuição de Poisson no contexto Bayesiano, levando em conta a dependência espacial, com o propósito de avaliar a relação entre a ocorrência da variável dependente com as variáveis demográficas, socioeconômicas e ambientais. Resultados: A taxa média de detecção foi de 6,73 casos por 10.000 hab., com 53.826 casos notificados no período. O estudo revelou que a distribuição dos casos de sexo masculino (57,75%) apresentou maior proporção em relação ao feminino (42,25%), havendo predominância da doença na faixa etária >15 anos (89,87%). A alta ocorrência na classificação operacional multibacilar (60,10%) é um forte indicativo decorrente do longo período de incubação da doença somado ao não diagnóstico precoce. A análise da distribuição dos agregados espaciais identificou 14 (7 de risco alto e 7 de risco baixo) e 6 (3 de risco alto e 3 de risco baixo) agrupamentos espaciais, considerando-se 10% e 50% da população em risco, respectivamente, em áreas com taxas de detecção alta e que possuem baixa qualidade de vida. O estimador Bayesiano empírico local possibilitou gerar índices corrigidos e com menores instabilidades. A análise de regressão múltipla espacial mostrou que as variáveis índice Gini, bioma predominante cerrado/caatinga e percentual de população urbana tiveram associação positiva e significativa para explicar o risco relativo (RR) no estado do Maranhão. Conclusões: O estudo mostrou que existem aglomerados com elevado risco para transmissão da hanseníase no estado do Maranhão. A associação entre o risco relativo da hanseníase e o percentual de população urbana indica que a hipótese que associa o M. leprae e a população que vive em condições de acentuada desigualdade socioeconômica ainda é forte. Essa hiperendemicidade pode demonstrar que o crescimento da população urbana é um preditor de incidência da hanseníase, face à urbanização descontrolada e ao fluxo de migrantes advindos de diferentes espaços rurais. Foi possível identificar áreas prioritárias para implementação de programas eficazes de controle de hanseníase no estado do Maranhão. / Leprosy, a chronic stigmatizing disease with the potential to cause neurological damage resulting from infection by Mycobacterium leprae. Current epidemiological studies have used clinical and spatial analysis for mapping of the main occurrence of disease outbreaks and high-risk areas. Analyze the municipalities of Maranhão state regarding the distribution of leprosy cases becomes another tool in the prevention and control of leprosy in the state by numerous factors like behaves as hyper-endemic area of leprosy; It presents intense migration to other interstate cities; and has great social contrasts marked by little or no basic infrastructure in some areas of several municipalities.. Objectives: To analyze the spatiotemporal distribution of leprosy in the Maranhão state, from 2001 to 2013. To identify the spatiotemporal clusters occurrence of probable high transmission (risk) and check for association of this distribution of relative risk (RR) detection rates of the disease with the variables of geographic context as socioeconomic and environmental. Methodology: Clinical and epidemiological data was obtained from the Ministry of Healths Disease Reporting System and demographic data, environmental and digital cartographic bases were obtained from the Brazilian Geography and Statistics Institute. An ecological approach to trends transmissibility of spatiotemporal patterns, using the methods: spatial scan to identification the clusters of risk, considering the Discrete Poisson probability distribution model; empirical Bayesian method was applied for local rate flattening, using data from municipalities having as building strategy the criterion of contiguity; ecological regression modeling with considering a Poisson distribution in the Bayesian context, taking into account the spatial dependence, in order to evaluate the relationship between the occurrence of the dependent variable with demographic, socioeconomic and environmental variables. Results: The mean detection rate was 6.73 cases per 10,000 inhabitants, with 53,826 reported cases. The study revealed that the distribution of male cases (57.75%) showed a predominance over female (42.25%), with predominance of the disease in the age group upper than 15 years (89.87%). The high occurrence in operational classification multibacillary (60.10%) is a strong indication due to the long incubation period of the disease added to no early diagnosis. The analysis of the distribution of spatial clusters identified 14 (7 high risk and 7 low risk) and 6 (3 high risk and 3 low risk) spatial clusters, considering 10% and 50% of the population at risk in areas with high detection rates and which have low quality of life. Local empirical Bayes estimator allowed to generate fixed and minor instabilities indexes. The best results of modeling to spatial multiple regression analysis for the relative risk (RR) presented for the variables Gini index, cerrado/caatinga biome and percentage of urban population. Conclusions: The study showed that there are clusters at high risk for transmission of leprosy in the Maranhao state. The association between the relative risk of leprosy and the percentage of urban population indicates that the hypothesis that associates M. leprae and the population living in severe socioeconomic inequality is still strong. This hyperendemicity can demonstrate that the growth of the urban population is a predictor incidence of leprosy due to uncontrolled urbanization and the influx of migrants coming from different rural areas.It was possible to identify priority areas for implementation of effective leprosy control programs in the Maranhão state.
282

Planejamento de experimentos no ensino da estatística e probabilidade nas séries finais do ensino fundamental II / Designs of experiments in the teaching of statistics and probability for the last years of elementary school

Homailson Lopes Passos 04 April 2018 (has links)
Este trabalho apresenta uma proposta para o ensino da Estatística e Probabilidade nas séries finais do Ensino Fundamental II. Seu objetivo é mostrar que a metodologia aqui adotada possibilita a aquisição de conceitos estatísticos e probabilísticos, assim como o desenvolvimento de habilidades pessoais e interpessoais. Trata de um projeto fundamentado em Planejamento de Experimentos com respaldo na aprendizagem ativa. Na sequência didática do projeto os alunos realizaram um experimento com aviões de papel no qual tiveram que responder, na prática, a seguinte questão \"Quais alterações podem ser feitas em um modelo de avião de papel para que ele permaneça mais tempo no ar?\". Para atestar a efetividade da sequência didática, foi construído e validado um Teste de Proficiência em Estatística e Probabilidade (TEPEP) com base nos fundamentos da Psicometria. A análise das características do teste foi feita por meio da Teoria Clássica dos Testes e da Teoria de Resposta ao Item. Foram sujeitos da pesquisa 391 alunos de escolas públicas e particulares da região do Vale do Paraíba, Estado de São Paulo. Desse total, 374 auxiliaram na validação do instrumento e os 17 alunos restantes participaram do projeto. Os resultados deste trabalho mostraram que o uso de Planejamento de Experimentos favoreceu a aprendizagem da Estatística e Probabilidade, desenvolvendo também outras competências. Em relação à validação do TEPEP, concluiu-se que os métodos psicométricos empregados têm grande potencial e devem ser mais explorados. Esta pesquisa apresenta, como produtos finais, a metodologia desenvolvida e o teste de proficiência construído, oferecendo ambos a professores e pesquisadores. / This work presents a proposal for teaching of Statistics and Probability, for the last years of Elementary School. Its objective is to show that the methodology adopted here allows the acquisition of statistical and probabilistic concepts, as well as the development of personal and interpersonal skills. It\'s a project with a didactic sequence grounded in Designs of Experiments, supported in active learning. In the didactic sequence of the project the students carried out an experiment with paper airplanes in which they had to answer, in practice, the following question \"What changes can be made to a paper airplane model so that it stays longer in the air?\". To attest the effectiveness of the didactic sequence, it was developed and validated a Proficiency Test in Statistics and Probability (PTSP), this using Psychometry. The analysis of the characteristics of the test was made through the Classical Test Theory and the Item Response Theory. The research subjects were a total of 391 students from public and private schools in the Vale do Paraíba region, State of São Paulo. Of this total, 17 students participated in the project. The other students (374) assisted in the test validation. The results of this research showed that the use of Design of Experiments favored the learning of Statistic and Probability, also to develop others competences. Regarding the validation of PTSP, it could be concluded that the psychometric methods used have potential and they should be more explored. This research acclaims, as final products, the developed methodology and the Proficiency test validated, both offered to teachers and researchers.
283

Condition-based maintenance policies for multi-component systems considering stochastic dependences / Politiques de maintenance conditionnelle pour des systèmes multi-composant avec dépendances stochastiques

Li, Heping 04 October 2016 (has links)
De nos jours, les systèmes industriels sont de plus en plus complexes tant du point de vue de leur structure logique que des diverses dépendances (dépendances économique, stochastiques et structurelles) entre leurs composants qui peuvent influencer l'optimisation de la maintenance. La Maintenance conditionnelle qui permet de gérer les activités de maintenance en fonction de l’information de surveillance a fait l’objet de beaucoup d'attention au cours des dernières années, mais les dépendances stochastiques sont rarement utilisées dans le processus de prise de décision. Par conséquent, cette thèse a pour objectif de proposer des politiques de maintenance conditionnelle tenant compte des dépendances économiques et stochastiques pour les systèmes multi-composant. En termes de dépendance économique, les politiques proposées sont conçues pour permettre de favoriser les opportunités de grouper des actions de maintenance. Une règle de décision est établie qui permet le groupement de maintenances avec des périodes d'inspection différentes. La dépendance stochastique causée par une part de dégradation commune est modélisée par copules de Lévy. Des politiques de maintenance conditionnelle sont proposées pour profiter de la dépendance stochastique.Nos travaux montrent la nécessité de tenir compte des dépendances économiques et stochastiques pour la prise de décision de maintenance. Les résultats numériques confirment l’avantage de nos politiques par rapport à d’autres politiques existant dans la littérature / Nowadays, industrial systems contain numerous components so that they become more and more complex regarding the logical structures as well as the various dependences (economic, stochastic and structural dependences) between components. The dependences between components have an impact on the maintenance optimization as well as the reliability analysis. Condition-based maintenance which enables to manage maintenance activities based on information collected through monitoring has gained a lot of attention over recent years but stochastic dependences are rarely used in the decision making process. Therefore, this thesis is devoted to propose condition-based maintenance policies which take advantage of both economic and stochastic dependences for multi-component systems. In terms of economic dependence, the proposed maintenance policies are designed to be maximally effective in providing opportunities for maintenance grouping. A decision rule is established to permit the maintenance grouping with different inspection periods. Stochastic dependence due to a common degradation part is modelled by Lévy and Nested Lévy copulas. Condition-based maintenance policies with non-periodic inspection scheme are proposed to make use of stochastic dependence. Our studies show the necessity of taking account of both economic and stochastic dependences in the maintenance decisions. Numerical experiments confirm the advantages of our maintenance policies when compared with other existing policies in the literature
284

Collage fiable pour l’espace : influence de la qualité des procédés et dimensionnement des assemblages / Reliable bonding for space applications : effect of process quality and assembly design

Bresson, Grégory 25 November 2011 (has links)
L’objectif de ce travail est de qualifier l’utilisation du collage structural en remplacement des solutions d’assemblage conventionnel dans les applications lanceur spatiaux. Si les gains potentiels tant en terme opérationnel qu’en terme de performance ne sont plus à démontrer il reste à mettre en place une démarche de dimensionnement qui garantisse le niveau important de fiabilité requis. Deux adhésifs structuraux de types époxydes ont été étudiés : l’EA9394 et le SW2216. Un travail important d’analyse physico-chimique des surfaces a été mené pour mettre en place un procédé d’assemblage stable et performant. L’analyse mécanique des liaisons collées a montré que l’adhésif subit en situation des sollicitations combinées de traction et de cisaillement. Un dispositif dérivé des essais Arcan à été proposé qui permet d’obtenir la réponse du film de colle sous forme de courbe contrainte déplacement relatif des substrats. La résistance mécanique mesurée au moyen des essais Arcan mais également sur le matériau adhésif montre une forte dispersion liée à un taux de porosité important mais également à une microstructure très hétérogène constituée d’une matrice époxyde et mélangée à des particules d’aluminium (adhésif EA9394). Enfin, le collage a été étudié à une échelle plus macroscopique en tentant de proposer un dimensionnement de liaison pour le lanceur démonstrateur Arcadia. Les lanceurs étant des structures à symétrie de révolution, un modèle semi-analytique de liaison collée axisymétrique a été développé.Ce travail a permis la mise en place d’une démarche d’analyse mettant en avant les analyses à l’échelle du film, de la liaison et de la structure pour mettre en évidence les nombreux phénomènes à l’origine d’une ruine prématurée de la liaison. Cette optimisation multiéchelle doit être conduite pour maximiser la résistance spécifique de la liaison en assurant le niveau de fiabilité requis pour cette application spatiale. / The objective of this study is to qualify the use of structural bonding as a replacement for conventional assembly solutions in space launcher applications. Potential benefits in fabrication and of final performance are already known, but it remains to establish a design approach to guarantee the high level of reliability required. Two epoxy structural adhesives have been studied: EA9394 and SW2216. A study of the physico-chemistry of surfaces has been effected in order to find a stable and strong bonding process. Mechanical analysis of bonded connections revealed that the adhesives could be subjected in use to mixed loadings in tension and shear. A device derived from Arcan tests has been proposed in which it is possible to obtain adhesive layer responses as stress/relative deformation for different substrates. Mechanical strength measured with the Arcan device and also on the bulk adhesive material revealed a high variability coming from a significant porosity fraction but also due to a highly heterogeneous microstructure constituted of epoxy matrix and aluminium particles (EA9394adhesive). Bonding has been studied on a macroscopic scale proposing connection design for the demonstration Arcadia launcher. A rocket being an axially symmetrical structure, a semi-analytical model of axisymmetric bonded connections has been developed. This study resulted in the finalisation of an analysis approach pointing to scale analysis of the adhesive layer, connection and structure in order to emphasise the many phenomena which could cause early bond failure. This multiscale approach should be effected to increase specific assembly strength while assuming the required reliability level for this spatial application.
285

Hodnocení vlivu změny vnitřních konstrukcí bytů na tržní hodnotu nemovitosti / Assessment of the Impact of Internal Construction Changes in Appartments on the Market Value

Vlastníková, Tereza January 2018 (has links)
The thesis analyses the impact of building renovation on the market price of a property. The analysis uses a particular type of property - a flat in a prefabricated house. A database of offered market prices before and after the building renovation was created. The price of the building renovation was made by an itemized budget. The data, which were obtain in this way, were then submitted to s detail analysis and statistical testing. The result of the analysis was to determine whether the cost of the building renovation impacted the market value of the property and whether it was evaluated
286

Statistická regulace v řízení jakosti - kontrola způsobilosti procesu a zařízení / Statistical process control in quality management - quality control of process and utility

Vrtílek, Filip January 2007 (has links)
The analysation of the quality system in the production, in the preparatoring and producing stage. The evaluation of modern phase in the preparatoring and producing stage. Summary of methods of solution in a problem of quality. Basic statistic methods and methods of management of quality. Basic mathematics term in statistics and SPC. Valuation of numerical characteristics and test of statistical hypotheses. Process of creating of machine and process card of regulations. Pc program SPC - TEST
287

Různé metody odhadu bodu změny / Various change point estimation methods

Šimonová, Soňa January 2020 (has links)
This thesis aims to give a comprehensive account of some of the most recent methods of a change point estimation. The literature on the change point estimation shows a variety of approaches to deal with this subject. Among them, tests based on the popular CUSUM process, likelihood ratio tests, wild binary segmentation and some of the most recent techniques on the change point estimation in panel data are all covered by this paper. The case of dependent panels is discussed as well. The practical part of the study is focused on application of the wild binary segmentation method on weekly log-returns of the Dow Jones stock index. Firstly, we fit a GARCH model to the analysed time series. We next use the wild binary segmenatation method to detect structural changes in the mean of the original time series. Next, we apply the same method to the residuals from the GARCH fit. We analyse several penalization criteria proposed by previous studies and evaluate their effects on the estimated number and locations of the change points in the given data set. 1
288

Investigating the Correlation Between Marketing Emails and Receivers Using Unsupervised Machine Learning on Limited Data : A comprehensive study using state of the art methods for text clustering and natural language processing / Undersökning av samband mellan marknadsföringsemail och dess mottagare med hjälp av oövervakad maskininlärning på begränsad data

Pettersson, Christoffer January 2016 (has links)
The goal of this project is to investigate any correlation between marketing emails and their receivers using machine learning and only a limited amount of initial data. The data consists of roughly 1200 emails and 98.000 receivers of these. Initially, the emails are grouped together based on their content using text clustering. They contain no information regarding prior labeling or categorization which creates a need for an unsupervised learning approach using solely the raw text based content as data. The project investigates state-of-the-art concepts like bag-of-words for calculating term importance and the gap statistic for determining an optimal number of clusters. The data is vectorized using term frequency - inverse document frequency to determine the importance of terms relative to the document and to all documents combined. An inherit problem of this approach is high dimensionality which is reduced using latent semantic analysis in conjunction with singular value decomposition. Once the resulting clusters have been obtained, the most frequently occurring terms for each cluster are analyzed and compared. Due to the absence of initial labeling an alternative approach is required to evaluate the clusters validity. To do this, the receivers of all emails in each cluster who actively opened an email is collected and investigated. Each receiver have different attributes regarding their purpose of using the service and some personal information. Once gathered and analyzed, conclusions could be drawn that it is possible to find distinguishable connections between the resulting email clusters and their receivers but to a limited extent. The receivers from the same cluster did show similar attributes as each other which were distinguishable from the receivers of other clusters. Hence, the resulting email clusters and their receivers are specific enough to distinguish themselves from each other but too general to handle more detailed information. With more data, this could become a useful tool for determining which users of a service should receive a particular email to increase the conversion rate and thereby reach out to more relevant people based on previous trends. / Målet med detta projekt att undersöka eventuella samband mellan marknadsföringsemail och dess mottagare med hjälp av oövervakad maskininlärning på en brgränsad mängd data. Datan består av ca 1200 email meddelanden med 98.000 mottagare. Initialt så gruperas alla meddelanden baserat på innehåll via text klustering. Meddelandena innehåller ingen information angående tidigare gruppering eller kategorisering vilket skapar ett behov för ett oövervakat tillvägagångssätt för inlärning där enbart det råa textbaserade meddelandet används som indata. Projektet undersöker moderna tekniker så som bag-of-words för att avgöra termers relevans och the gap statistic för att finna ett optimalt antal kluster. Datan vektoriseras med hjälp av term frequency - inverse document frequency för att avgöra relevansen av termer relativt dokumentet samt alla dokument kombinerat. Ett fundamentalt problem som uppstår via detta tillvägagångssätt är hög dimensionalitet, vilket reduceras med latent semantic analysis tillsammans med singular value decomposition. Då alla kluster har erhållits så analyseras de mest förekommande termerna i vardera kluster och jämförs. Eftersom en initial kategorisering av meddelandena saknas så krävs ett alternativt tillvägagångssätt för evaluering av klustrens validitet. För att göra detta så hämtas och analyseras alla mottagare för vardera kluster som öppnat något av dess meddelanden. Mottagarna har olika attribut angående deras syfte med att använda produkten samt personlig information. När de har hämtats och undersökts kan slutsatser dras kring hurvida samband kan hittas. Det finns ett klart samband mellan vardera kluster och dess mottagare, men till viss utsträckning. Mottagarna från samma kluster visade likartade attribut som var urskiljbara gentemot mottagare från andra kluster. Därav kan det sägas att de resulterande klustren samt dess mottagare är specifika nog att urskilja sig från varandra men för generella för att kunna handera mer detaljerad information. Med mer data kan detta bli ett användbart verktyg för att bestämma mottagare av specifika emailutskick för att på sikt kunna öka öppningsfrekvensen och därmed nå ut till mer relevanta mottagare baserat på tidigare resultat.
289

Scientometrické hodnocení vědy se zaměřením na Českou republiku / Scientometric research evaluation with focus on the Czech Republic

Troupová, Alžběta January 2011 (has links)
(in English) The master thesis is focused on the scientometric methods of research and development evaluation and their use in particular system applied in the Czech Republic. Its introductory part presents the field of scientometrics, scientometric and bibliometric indicators and citation indices. Chapter 7 deals with research and development evaluation in Czech Republic, especially with Research Evaluation Guidelines and describes its assesment rules, results and changes due to its annual actualization. A battle of wills between the Guidelines supporters and opponents is the topic of chapter 8, in particular in the context of reallocation of institutional funding according to the Guidelines. Ideas and opinions of prominent scientists and policymakers are being presented followed by brief treatise on Czech system of research and development evaluation audit carried out by the company Technopolis Limited. In the conclusion the author summarizes and debates positives and negatives of the Czech system of science evaluation.
290

Die Bürger Dresdens und ihre Städtische Bibliothek: Ausgewählte Ergebnisse der Kommunalen Bürgerumfrage 2010

Becker, Antje 15 June 2011 (has links)
Im letzten Jahr wendete sich die Stadt Dresden nach dem Zufallsprinzip an ihre Einwohner, mit der Bitte, zwei Fragebögen auszufüllen. Deren Fragen richteten sich hauptsächlich auf die Lebensbedingungen am Wohnort. Die Datenerfassung für die eingegangenen Fragebögen endete im Dezember 2010. Es konnten 4.534 Fragebögen ausgewertet werden. Die rücklaufquote lag bei 46 % und ist damit die zweitbeste in der Geschichte der kommunalen Bürgerumfragen Dresdens. Wie bereits in Kommunalen Bürgerumfragen zurückliegender Jahre, insbesondere 2007, gibt die Kommunale Bürgerumfrage 2010 erneut Gelegenheit dazu, interessante Aspekte der Nutzung der Städtischen Bibliotheken, im Vergleich zu anderen kulturellen Einrichtungen Dresdens, zu hinterfragen.

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