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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.
21

On strategic incentives and the management of stochastic renewable resources /

Hennlock, Magnus, January 2005 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2006. / Härtill 4 uppsatser.
22

Economic consequences of collaborative arrangements in the agricultural firm /

Larsén, Karin, January 2008 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2008. / Härtill 5 uppsatser.
23

Use of the intermediate category test in arithmetic disability subtypes

Nyberg, Timothy Jacob January 2005 (has links) (PDF)
Thesis (Ph. D.) -- University of Texas Southwestern Medical Center at Dallas, 2005. / Vita. Bibliography: 87-97.
24

Multiple comparison techniques for order restricted models

Nashimoto, Kane, January 2004 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaves 159-165). Also available on the Internet.
25

Multiple comparison techniques for order restricted models /

Nashimoto, Kane, January 2004 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaves 159-165). Also available on the Internet.
26

A comparison of four estimators of a population measure of model misfit in covariance structure analysis

Zhang, Wei. January 2005 (has links)
Thesis (M. A.)--University of Notre Dame, 2005. / Thesis directed by Ke-Hai Yuan for the Department of Psychology. "October 2005." Includes bibliographical references (leaves 60-63).
27

Electron beam diagnosis for weld quality assurance

Kaur, Aman P. January 2016 (has links)
Electron beam welding is used for fabricating critical components for the aerospace and nuclear industries which demand high quality. The cost of materials and associated processes of fabrication is also very high. Therefore, manufacturing processes in these industries are highly controlled. However, it has been found that even minor changes in the electron beam gun itself can produce large variations in beam characteristics, leading to unpredictable welding performance. Hence, it is very important to ensure the beam quality prior to carrying out welds. This requires some kind of device and process to characterise the electron beam to indicate variations. A detailed review of different technologies used to develop devices to characterise electron beams has been carried out. At this time, it is uncommon for beam measurement to be carried out on production EBW equipment. Research carried out for this thesis is focused on development of a novel approach to characterise the electron beams using a slit-probe to maintain the quality of the welds. The challenge lies in deriving relevant features from the acquired probe signal which can effectively differentiate between the beams of different quality. Wavelet transformation, with its advantages over other methods for simultaneous time and frequency localization of signals, has found its application to feature extraction in many pattern based classifications. This technique has been used to analyse probe signals considering that different quality beams will possess unique signal profiles in the form of their distribution of energies with respect to frequency and time. To achieve the aim of the thesis, an experimental approach was used by carrying out melt runs on Ti-6Al-4V plates focusing on aerospace requirements, and varying beam properties and acquiring probe signals for all beam settings. Extracted features from the probe signals have been used in classification of the electron beams to ensure these will produce welds within the tolerance limits specified by aerospace standards for quality assurance. The features vector was compiled following statistical analysis to find the significant beam characteristics. By analysing the performance of classifier for different combination of parameters of the features vector, the optimum classification rate of 89.8% was achieved by using the parameters derived from wavelet coefficients for different decomposition levels. This work showed that the use of wavelet analysis and classification using features vectors enabled identification of beams that would produce welds out-of-tolerance. Keywords: Electron beam welding, probe devices, electron beam characterisation, quality assurance, wavelet transform, features vector, linear discriminant classifier, weld profiles, weld defects.
28

Alterações de saúde, resiliência e qualidade de vida de discentes de graduação em enfermagem no primeiro ano letivo / Health changes, resiliency and quality of life of nursing degree students after the first academic-year

Rodrigo Marques da Silva 12 September 2017 (has links)
Introdução: Diferentes pesquisas apontam que os estressores acadêmicos podem impactar na saúde dos discentes de enfermagem. Por outro lado, sabe-se que alguns indivíduos são capazes de se adaptar a situações de adversidade (resiliência), apresentando melhores condições de saúde. No entanto, pouco se sabe se tais alterações estão relacionadas ao ingresso no curso superior, pois poucas pesquisas analisam tais alterações longitudinalmente, bem como as relações simultâneas entre os fenômenos de saúde e o papel da resiliência na melhoria da saúde dos discentes. Objetivos: identificar se ocorrem alterações na saúde, nos níveis de resiliência e na qualidade de vida de discentes após um ano do ingresso no curso de graduação em enfermagem; e analisar como se dão as relações simultâneas de causalidade entre estresse psicoemocional, sintomas depressivos, qualidade do sono e resiliência na explicação da qualidade de vida dos discentes um ano após o ingresso no curso. Método: Essa pesquisa organiza-se em duas etapas de abordagem quantitativa: metodológica (Calibração) e longitudinal. Na Fase 1, coletaram-se os dados com alunos do 2o, 3o e 4o anos (respectivamente 4o,6o e 8o semestres) de uma universidade estadual de São Paulo. Na etapa seguinte, a coleta ocorreu com os alunos do 1o ano (1o e 2o semestres de 2016) no início das aulas e ao final do ano letivo com os instrumentos já calibrados em duas universidades de São Paulo, uma estadual e outra federal. Nessas etapas, aplicaram-se os seguintes instrumentos: Formulário para caracterização sociodemográfica e acadêmica; Instrumento para Avaliação do Estresse em Discentes de Enfermagem, Center for Epidemiologic Studies Depression Scale, Índice de Qualidade de Sono de Pittsburgh; Escala de Resiliência de Wagnild & Young; e o Instrumento de Avaliação de Qualidade de Vida. Utilizou-se a análise fatorial confirmatória para a calibração dos instrumentos e o teste ANOVA para modelos mistos para analisar as alterações de saúde, resiliência e qualidade de vida ao longo do ano letivo. A Modelagem de Equações Estruturais foi utilizada para compreender as relações de dependência entre as variáveis. Resultados: A estrutura fatorial e a consistência interna foram satisfatórias para explicar os fenômenos. 110 discentes participaram da calibração dos instrumentos e 117 compuseram a fase longitudinal em março e 100 em dezembro de 2016. Verificou-se aumento significativo do estresse psicoemocional em todos os domínios do instrumento; redução da duração e da qualidade subjetiva do sono; e aumento do estresse psicoemocional geral e dos sintomas depressivos. O modelo hipotetizado final presentou boa qualidade de ajuste e de resíduos. O estresse psicoemocional reduziu a qualidade do sono e aumentou a intensidade dos sintomas depressivos, os quais diminuíram a qualidade de vida direta e indiretamente (através do estresse). A resiliência reduziu os níveis de estresse e sintomas depressivos e melhorou a qualidade do sono. Conclusão: O ambiente acadêmico de enfermagem apresenta potencial para doenças, com impacto à qualidade de vida. O estresse psicoemocional é o preditor dos fenômenos analisados e a resiliência um fator protetor contra o estresse. Sugere-se que as instituições repensem seus elementos curriculares, promovam a resiliência e criem espaços de promoção à saúde dos alunos. / Introduction: Several investigations highlight that academic stressors may impact on the health status of undergraduate nursing students. On other hand, the previous literature confirms that few individuals are able of adapting to adverse situations and, so, present a better health condition. However, it is not clear if the changes in health status are related to the nursing degree program once: few studies have longitudinally assessed health status changes; the simultaneous relations among health phenomena; and the potential role of resilience on nursing students health. Objectives: to identity if the health status, resilience and quality of life of nursing degree students change after the first academic-year; and to assess how the simultaneous relations of causality among psycho-emotional stress, depressive symptoms, sleep quality and resilience are arranged to explain the quality of life of nursing degree students after the first academic-year. Method: this research is organized in two phases, both of quantitative approach: Phase 1-methodologic (tools calibration) assessment; and Phase 2- longitudinal study. In the Phase 1, data were gathered from students enrolled in the 2nd, 3rd and 4th academic years (respectively 4th,6th, and 8th semesters) of a state university of Sao Paulo. In the next phase, we gathered the data from 1st year (1st and 2nd semesters of 2016) students at the starting of classes and one year after the first data collection with the calibrated instruments in two universities of Sao Paulo- one state and other federal. In these phases, we applied the following instruments: demographic and academic form; Instrument for stress evaluation in nursing students, Center for Epidemiologic Studies Depression Scale, Pittsburgh Sleep Quality Index; Connor-Davidson Resilience Scale; and the Instrument for Quality of Life Assessment. We used the confirmatory factor analysis to calibrate the instruments and the ANOVA for mixed models to assess the changes in health status across the first academic year. The Structural Equation Modelling was applied to evaluate the dependency relations among the variables. Results: the factorial structure and the internal consistency were satisfactory to explain the phenomena. 110 students attended the instruments calibration phase. In the longitudinal phase, 117 students were included in March and 100 in December 2016. We found a significant increase of psycho-emotional stress in all instruments domains; a decrease of duration and subjective quality of sleep; and an increase of general psychoemotional stress and depressive symptoms. The final hypothesized model showed good adjustment for quality and residues indexes. The psycho-emotional stress reduced the sleep quality and increased the depressive symptoms, which decreased the quality of life directly and indirectly (Through the stress). Resilience relieved the stress levels and the depressive symptoms and improved the sleep quality. Conclusion: the nursing academic environment has potential for illnesses, with impact on quality of life. The psycho-emotional stress is predictor of the assessed phenomenon and resilience is a protective factor against stress. We suggest that the teaching institutions rethink the curricular elements, promote the resilience and create spaces for students health promotion.
29

Tecnicas geoestatisticas aplicadas na modelagem da saturação de oleo / Geostatistical tecniques applied on oil saturation modeling

Zanão, Rodrigo 12 August 2018 (has links)
Orientador: Alexandre Campane Vidal / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica e Instituto de Geociencias / Made available in DSpace on 2018-08-12T12:03:21Z (GMT). No. of bitstreams: 1 Zanao_Rodrigo_M.pdf: 2677422 bytes, checksum: ee9f24a2e2f572f3b3733817353925b8 (MD5) Previous issue date: 2008 / Resumo: A perfilagem de poços revestidos com ferramentas que quantificam a saturação de água foi realizada no aqui denominado Campo de Estudo, localizado na Bacia do Recôncavo, considerado maduro e com acumulações de hidrocarbonetos remanescentes presentes na Formação Sergi. De posse das informações advindas desta ferramenta e, juntamente com as demais informações como porosidade e litofácies, foram utilizadas as técnicas geoestatísticas krigagem ordinária (KO) e krigagem com deriva externa (KDE) para a criação de modelos de porosidade e saturação de água para o campo estudado. Os resultados da modelagem da variável saturação de água ao longo do tempo permitiram caracterizar a evolução da saturação de água no campo e a identificação de porções de óleo remanescente. De posse das informações petrofísicas e do modelo de saturação foi efetuado o cálculo do volume para os três intervalos temporais analisados, obtendo-se assim valores que permitiram constatar a dinâmica da variável Sw ao longo dos anos e verificar a existência de óleo remanescente no reservatório. / Abstract: Cased well logging with tools which quantify the water saturation had been done in the Study Field, located on Recôncavo Basin, considered mature and with reminiscent hydrocarbonates storage in the Sergi Formation. The geostatistical techniques of ordinary kriging and kriging with external drift had been used to the studied field for porosity and water saturation of development model. The results of the modeling of water saturation variable in steps of time allowed to characterized the evolution of the water saturation in the field and the identification of the remaining oil portions. With information models of petrophysics and the fluids saturation , the oil volume calculus for the three temporal intervals analyzed had been done. Values had been obtained which allowed proving the dynamic of Sw variable along the years and verifying the reminiscent oil in the reservoir. / Mestrado / Reservatórios e Gestão / Mestre em Ciências e Engenharia de Petróleo
30

Desenvolvimento e validação de um instrumento para avaliar espiritualidade: Escala de Atitudes Relacionadas à Espiritualidade (ARES) / Development and validation of an instrument to evaluate spirituality: Spirituality-Related Attitude Scale (ARES)

Braghetta, Camilla Casaletti 08 August 2017 (has links)
Objetivos: Desenvolver um novo instrumento para avaliar espiritualidade e realizar análises psicométricas de validade e confiabilidade. Métodos: O instrumento foi elaborado através de quatro etapas: fundamentação teórica, investigação sobre definições de espiritualidade na população geral, elaboração da primeira versão por um comitê de especialistas e teste de compreensibilidade. Nas análises psicométricas, o instrumento foi submetido à avaliação de juízes e posteriormente, foi testado em estudantes de medicina (N=85) e em uma população de religiosos (N=85), para cálculo de consistência interna, análise fatorial exploratória e confiabilidade teste-reteste. Resultados: O instrumento desenvolvido, a Escala de Atitudes Relacionadas à Espiritualidade (ARES), apóia-se na compreensão sobre espiritualidade no contexto brasileiro e em bases teóricas. Apresentou análises psicométricas apropriadas: a análise fatorial exploratória apontou uma estrututura unidimensional, o alfa de Cronbach encontrado em cada item foi >= 0,98 e o Coeficiente de Correlação Intraclasse (CCI=0,98) apontou boa reprodutibilidade da escala. Conclusão: ARES é um instrumento unidimensional, desenvolvido em idioma português, que apresentou consistência interna excelente e indicou ser reprodutível na população avaliada. São necessários mais estudos para verificar se ARES é aplicável em amostra com baixa escolaridade e em outros contextos culturais e religiosos. A escala ARES permite operacionalizar o construto espiritualidade em pesquisas quantitativas / Objectives: Develop a new instrument devised to measure spirituality, able to perform psychometric analysis of validity and reliability. Methods: The instrument was elaborated through four processes: theoretical foundation, a population based investigation about possible definitions of spirituality, a first version was achieved by a committee of experts in Spirituality along with a comprehension test. In psychometric analysis, the analysis was evaluated by judges, then tested in a population of medical students (N = 85) and in a religious population (N = 85), in order to calculate internal consistency, exploratory factor analysis (EFA) and reliability, through test-retest. Results: The instrument, ARES, a Spirituality-Related Attitudes Scale, was based on theoretical understandings of spirituality in the Brazilian context. It presented an appropriate psychometric analysis: the EFA indicated a one-dimensional structure, the Cronbach\'s Alpha found each item at >= 0.98 and the Intraclass Correlation Coefficient (ICC = 0.98) indicated good reproducibility of the scale. Conclusion: ARES is a one-dimensional instrument, developed in the Portuguese language, which presented an excellent internal consistency and indicated to be reproducible in the evaluated population. Further studies are needed to verify if ARES is applicable to other population samples, for example, a low SES and other cultural/religious contexts. The ARES scale allows for operationalization of the construct of spirituality in quantitative researches

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