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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.
11

二次元噴流と平行に置かれた平板との衝突により形成される渦構造のスケールと乱れの分布

河合, 勇太, KAWAI, Yuta, 辻, 義之, TSUJI, Yoshiyuki, 久木田, 豊, KUKITA, Yutaka 04 1900 (has links)
No description available.
12

Comparison of Grab, Air, and Surface Results for Radiation Site Characterization

Glassford, Eric 04 August 2011 (has links)
No description available.
13

Space-Frequency Regularization for Qualitative Inverse Scattering

Alqadah, Hatim F. January 2011 (has links)
No description available.
14

An Examination of Arousal States in Novice Whitewater Kayakers During a Weekend Instructional Experience

Dahlstrom, Erik A. 29 July 2008 (has links)
No description available.
15

Asymptotic and Factorization Analysis for Inverse Shape Problems in Tomography and Scattering Theory

Govanni Granados (18283216) 01 April 2024 (has links)
<p dir="ltr">Developing non-invasive and non-destructive testing in complex media continues to be a rich field of study (see e.g.[22, 28, 36, 76, 89] ). These types of tests have applications in medical imaging, geophysical exploration, and engineering where one would like to detect an interior region or estimate a model parameter. With the current rapid development of this enabling technology, there is a growing demand for new mathematical theory and computational algorithms for inverse problems in partial differential equations. Here the physical models are given by a boundary value problem stemming from Electrical Impedance Tomography (EIT), Diffuse Optical Tomography (DOT), as well as acoustic scattering problems. Important mathematical questions arise regarding existence, uniqueness, and continuity with respect to measured surface data. Rather than determining the solution of a given boundary value problem, we are concerned with using surface data in order to develop and implement numerical algorithms to recover unknown subregions within a known domain. A unifying theme of this thesis is to develop Qualitative Methods to solve inverse shape problems using measured surface data. These methods require very few a priori assumptions on the regions of interest, boundary conditions, and model parameter estimation. The counterpart to qualitative methods, iterative methods, typically require a priori information that may not be readily available and can be more computationally expensive. Qualitative Methods usually require more data.</p><p dir="ltr">This thesis expands the library of Qualitative Methods for elliptic problems coming from tomography and scattering theory. We consider inverse shape problems where our goal is to recover extended and small volume regions. For extended regions, we consider applying a modified version of the well-known Factorization Method [73]. Whereas for the small volume regions, we develop a Multiple Signal Classification (MUSIC)-type algorithm (see for e.g. [3, 5]). In all of our problems, we derive an imaging functional that will effectively recover the region of interest. The results of this thesis form part of the theoretical forefront of physical applications. Furthermore, it extends the mathematical theory at the intersection of mathematics, physics and engineering. Lastly, it also advances knowledge and understanding of imaging techniques for non-invasive and non-destructive testing.</p>
16

Impact du cancer de la prostate sur la vie quotidienne du couple âgé

Petit, Sylvie 03 December 2009 (has links)
Les recherches récentes menées sur le cancer s’accordent sur le fait que l’âge serait un des principaux facteurs de risque (Tubiana, 2002). C’est notamment le cas du cancer de la prostate, la plupart des cas étant constatés entre 60 et 90 ans (âge moyen de détection : 73 ans). Les personnes âgées se trouvent alors confrontées à différentes problématiques afférentes à la vieillesse, dont le cancer fait partie. Faire face à cette maladie n’est pas le seul défi du patient âgé, le cancer perturbant sa vie au niveau de tout son environnement affectif et social. Nous nous intéressons dans cette thèse à connaître l’impact psychologique du cancer de la prostate sur la vie quotidienne des patients âgés et de leurs épouses. Nous présentons les résultats menés auprès de 96 patients atteints du cancer de la prostate et de leur conjointe recrutés sur deux centres régionaux de lutte contre le cancer. Nous mettrons en place une nouvelle méthodologie : la méthode écologique d’échantillonnage des expériences qui se déroule sur 3 cycles d’évaluations durant 4 jours (en début de traitement, en milieu de traitement et en fin de traitement). Cette méthode nous permet d’établir les liens entre variables (/heure, /jour, /sujet, entre sujets et au sein du couple), et d’observer et de comparer l’ajustement des patients et de leur conjointe suivant différents âges (Swendsen, 1997 ; Czikszentmihalyi, 1984). Nos résultats mettent en évidence trois points essentiels : Tout d’abord il s’agit de distinguer les différences de ressentis et de stratégies de coping selon l’âge des couples pris en charge. Ensuite, le second point important de cette recherche est la notion d’inter individualité. Cette étude discrimine tout à fait les attitudes et les émotions que peuvent vivre au quotidien les patients des épouses. Enfin, le troisième point concerne le temps de la prise en charge. Il existe une réelle progression des ressentis et de l’ajustement psychologique des couples tout au long du traitement. Cette étude permet d’affiner nos connaissances sur le couple âgé confronté à la maladie et, plus spécifiquement, sur son ajustement émotionnel et sa qualité de vie lorsqu’il lui faut faire face au cancer de la prostate. Cette recherche est financée par la Ligue Nationale de Lutte Contre le Cancer, France. / Recent research consistently indicates that age is a major risk factor for cancer (Tubiana, 2002). Such is the case of prostate cancer, which is typically detected between the ages of 60 and 90 (average age of detection: 73 years). Coping with the physical effects of cancer is not the only challenge for elderly patients; cancer may also affect patient’s emotional and social lives as well. The current study presents results of an experience sampling study on the psychological impact of prostate cancer on the daily lives of elderly patients and their wives. We present data on 96 patients with prostate cancer and their spouse who were recruited from two Regional Center for the Fight Against Cancer in Bordeaux, France. Participants completed 3 daily assessments for 4 days (at the beginning of treatment, in the middle of treatment and at the end of treatment). The methodology has a number of advantages, including that it allows us to establish the relationship between variables (coping, quality of life, anxiety and depression), between subjects, and within the couple. The methodology also allows us to observe and compare the adjustment of patients and their partner following different ages (Swendsen, 1997, Czikszentmihalyi, 1984). Our results schowing three key points: First, we distinguiging the differences of feeling and coping strategies by spouses’age. The second point concern the concept of interindividual. This study discriminate behavior and emotions in everyday life of couples. The third important point concerns time management. There is an increased in feeling and psychosocial adjustement on the treatment. This study will help us to refine our knowledge and understanding of emotional adjustment and quality of life of patients with prostate cancer and their spouses. We will thus be able to realize the importance of taking into account the couple and not just patients in psychological interventions. This research is being funded by the National League for the Fight against Cancer, France.
17

Sistema radicular de cana-de-açúcar e identificação de raízes metabolicamente ativas. / Sugar cane root system and identification of roots with active metabolism.

Faroni, Carlos Eduardo 13 January 2005 (has links)
O conhecimento da dinâmica de crescimento das raízes da cana-de-açúcar, bem como da arquitetura de seu sistema radicular, permite melhor compreensão das relações entre a planta e o seu ambiente de produção, possibilitando o manejo a partir de práticas agrícolas mais eficientes e sustentáveis que resultem em aumento de produtividade e longevidade da cultura. O presente estudo teve por objetivo desenvolver um método para determinação da distribuição e do desenvolvimento de raízes metabolicamente ativas de cana-de-açúcar no solo, por meio da técnica da diluição do isótopo 15N, associado aos métodos de amostragem com monólito e sonda amostradora de raízes. O experimento foi realizado em área comercial de cana-de-açúcar na região canavieira de Piracicaba, Estado de São Paulo, em LATOSSOLO VERMELHO distrófico arenoso, com uma segunda rebrota do cultivar RB85 5156. O delineamento experimental foi em blocos subdivididos no tempo, com as amostragens de raízes realizadas a cada 50 a 60 dias de janeiro a junho de 2004. A uréia foi o veículo de fornecimento do marcador isotópico 15N, por meio de solução aplicada às folhas das plantas. Após colheita da parte aérea, realizada 96 horas após a aplicação da solução de uréia, foram abertas trincheiras, transversalmente à linha da cultura, com dimensões de 1 m de comprimento e 1,4 m de largura. Amostras foram colhidas por meio de monólito nas profundidades de 0 a 20, 20 a 40, 40 a 60 e 60 a 80 cm, na projeção da linha da cultura e lateralmente nas distâncias de 14 a 42 cm e de 42 a 70 cm da linha da cultura. Outras amostras foram colhidas com sonda amostradora de raízes, paralelamente à parede interna das trincheiras, a 10 cm de distância do local onde foram retirados os monólitos, nas mesmas profundidades e nas distâncias de 28 e 56 cm da linha. Em cada profundidade de amostragem, e na projeção da linha da cultura, foram separadas amostras de raízes visualmente ativas. Estas amostras forma consideradas padrão para a determinação por diluição isotópica de raízes com metabolismo ativo. As determinações do teor de N e de abundância de 15N em amostras de planta e de solo foram realizadas em um espectrômetro de massas modelo ANCA-SL da Eurapa Scientific Ltda. Os resultados mostraram que o método da diluição isotópica com 15N possibilitou avaliar a massa de raízes com metabolismo ativo e sua distribuição no solo, e o método de amostragem de raízes com a sonda foi viável em comparação com a amostragem do monólito, nas seguintes condições: na quantificação de raízes nas profundidades de 0 a 20, 20 a 40 e 60 a 80 cm do perfil do solo para raízes totais, e nos 20 cm superficiais do solo, profundidade na qual a massa de raízes foi maior, para raízes metabolicamente ativas. / Knowledge about of sugarcane root growth dynamic, as well as the root system architecture of sugarcane crop allows understanding better the relationships between the plant and its environment. This knowledge is important to define the crop management with most efficiency and using sustainable practices, to increasing both sugarcane crop yield and longevity. The aim of this study was to evaluate a method in order to determine sugarcane roots with active metabolism and its distribution and growth in the soil profile, by using isotopic dilution technique with 15N associated with sampling by monolite and probe. The experiment was conducted in the sugarcane field, on the region of Piracicaba, State of São Paulo, Brazil, by using the second rattoon of the variety RB 85 5156, grown in a Rhodic Hapludox. The experimental design was in randomized blocks, with four replications. The split plot was considered in relation to the time. The 15N tracer was applied in the plants as urea solution. The above ground part of sugarcane plants were harvested 96 hours after urea solution applications, and trenches with one meter of length and 1.4 meter width were opened transversely to sugarcane rows. Samples were taken by monolite in 0-20, 20-40, 40-60 and 60-80 cm of depth in the soil profile in the row projection and horizontally in the distances of 14 to 42 and 42 to 70 cm from the cane row. Samples were taken by probe in a parallel plan with the internal trench wall at 10 cm of distance from the spot where monolites were collected, in the same depths and at 28 and 56 cm from the row. Roots visually assumed as metabolisms active were separated to each sampling depth and to row lateral projection and were considered standards to determine active roots. Determinations of N contents and 15N abundance in both plant and soil were carried on a mass spectrometer model ANCA-SL (Europa Scientific Ltda.). The results showed the isotopic dilution method with 15N allowed the evaluation of active roots mass and the root distribution in the soil. The root sampling method with probe was adequate comparing with root sampling by monolite in trench to quantify roots, in the following conditions: in the soil depths of 0 to 20, 20 to 40 and 60 to 80 cm to total roots; and in the first 20 cm of depth, where the root mass was higher to active roots.
18

Heavy-tail statistical monitoring charts of the active managers' performance

Chen, Chun-Cheng 03 August 2006 (has links)
Many performance measurement algorithms can only evaluate measure active managers' performance after a period of operating time. However, most investors are interested in monitoring the active managers' performances at any time, especially, when the performance is going down. So that the investors can adjust the targets and contents of their portfolios to reduce their risks. Yashchin,Thomas and David (1997) proposed to use a statistical quality control (SQC) procedure to monitor active managers' performances. In particular, they established the IR (Information Ratio) control charts under normality assumption to monitor the dynamic performances of active managers. However, the distributions of IR statistic usually possess fat tail property. Since the underlying distribution of IR is an important hypothesis in building up the control chart, we consider the heavy tail distributions, such as mixture normal and generalized error distribution to fit the IR data. Based on the fitted distribution, the IR control charts are rebuilt. By simulations and empirical studies, the remedial control charts are found to detect the shifts of active managers' performances more sensitively.
19

Estudo comparativo de dois métodos de avaliação da exposição potencial a agrotóxicos

Egito, Jose Lourenço do 15 July 2011 (has links)
Made available in DSpace on 2015-05-08T14:53:17Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2196529 bytes, checksum: 75f110a24c8313e076c09e6e941384a9 (MD5) Previous issue date: 2011-07-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Exposure assessment is an important phase to investigate toxicological risk and it is also relevant for planning surveillance action on farmer s health. This research has the objective of comparing sampling and census methods in order to evaluate chemical exposure. The studies were done in Petrolina PE in São Francisco River Valley in three different work conditions: on weeds, grape and on acerola crops using backpack spraying on August and November, 2010. It is an exploratory and descriptive study. It is also an experimental and quali-quantitative research. The instruments used to measure dermal exposure were: sampling method in which patches are fixed on farmer s outfit and census method in which farmers wear overalls for easy absorption. A questionnaire was applied in order to check the user profile and their functional situation at companies. To data analysis, it was used descriptive statistical parameters and test t - Student to compare sampling averages. The methods evaluated just one operation in activity simulation: hand spraying use. Experiments allowed result comparison among operators, body area, treatment types and farmer safety condition. The main results of activity simulation report that different operational performances happened among users. The biggest amounts were found on weed spraying: inferior limps at 225,4 mg/day (sampling) and 134,1 mg/day (sampling) and chest at 137,2 mg/day (sampling) and 13,5 mg/day (census); grape crops at 271,7 mg/day (sampling) and 136,5 mg/day (census) and chest at 400,3 mg/day (sampling) and 34,2 mg/day (census); acerola crops at 339,8 mg/day (sampling) and 158,7 mg/day (census) and chest at 126,5 (sampling) and 13,32 mg/day (census). The greatest skin exposure happened on grape crops at an average of 1057 mg/day (sampling) and 307,7 mg/day (census) in 7 hours per day. In order to classify safety working conditions, contamination risks were measured by simulated dermal exposure (EDS) and chronicle contamination by safety margin (MS). They were considered safe (MS > 1) treatment on weeds and grape crops in both methods. On acerola treatment, working conditions were classified as unsafe (MS < 1) for Folisuper 600 insecticide at exposure control need of 51, 7% sampling method and safe working condition (MS > 1) using census method. Before the results, we can conclude that there were high discrepancies among exposure assessment in all treatments, as sampling method presented overestimated values superior to 200% and census method showing more reliable and precise results presenting higher efficiency. / A avaliação da exposição é uma etapa importante para a investigação do risco toxicológico e indispensável para o planejamento de ações de vigilância à saúde do trabalhador rural. O presente estudo tem por objetivo comparar os métodos amostral e censitário de atividade para avaliação da exposição a agrotóxicos. Os estudos foram realizados no município de Petrolina PE no Submédio do Vale do rio São Francisco, em três condições de trabalho: em plantas daninhas, cultura da uva e da acerola com uso do pulverizador costal manual, no período de agosto e novembro de 2010. Trata-se de uma pesquisa tipo exploratório e descritivo, de caráter experimental e de abordagem quali-quantitativa. Os instrumentos utilizados para mensurar a exposição dérmica foram: o método amostral, que consiste no uso de coletores absorventes fixados na vestimenta do trabalhador e o método censitário, onde o trabalhador utiliza uma vestimenta de corpo inteiro e fácil absorção. Aplicou-se o questionário para verificar o perfil dos aplicadores e sua situação funcional nas empresas estudadas. Para análise dos dados fez-se uso dos parâmetros estatísticos descritivos e do teste t - Student para comparar as médias das amostras emparelhadas. Os dois métodos avaliaram apenas uma operação na simulação da atividade: as atividades de aplicação manual. Os experimentos permitiram comparar os resultados entre operadores, áreas do corpo, tipos tratamentos e condições de segurança do trabalhador. Os principais resultados da simulação da atividade apontam que: entre os aplicadores ocorreram diferentes performances operacionais em todos os tratamentos. As áreas mais atingidas foram no tratamento de plantas daninhas: os membros inferiores com 225,4 mg/dia (amostral) e 134,1 mg/dia (censitário) e tórax com 137,2 mg/dia (amostral) e 13,5 mg/dia (censitário); uva com 271,7 mg/dia (amostral) e 136,5 mg/dia (censitário) e tórax com 400,3 mg/dia (amostral) e 34,2 mg/dia (censitário); acerola com 339,8 mg/dia (amostral) e 158,7 mg/dia (censitário) e tórax com 126,5 (amostral) e 13,32 mg/dia (censitário). As maiores exposições dérmicas ocorreram no tratamento da cultura da uva que em média foi de 1057 mg/dia (método amostral) e 307,7 mg/dia (método censitário) para uma jornada de trabalhos de 7 horas/dia. Para classificar a segurança das condições de trabalho foram calculados os riscos de intoxicações agudas pela exposição dérmica simulada (EDS) e intoxicação crônica pelo cálculo da margem de segurança (MS). Foram classificadas como seguros (MS > 1) os tratamentos em plantas daninhas e cultura da uva em ambos os métodos. No tratamento da acerola as condições de trabalho foram classificadas como insegura (MS < 1) para o inseticida Folisuper 600 BR com necessidade de controle de exposição de 51,7% com o método amostral e condições de trabalho segura (MS > 1) com o método censitário. Diante dos resultados, concluiu-se que houve elevada discrepância entre as avaliações da exposição em todos os tratamentos, com o método amostral apresentando valores superestimados, com diferenças superiores a 200% e que o método censitário apresentou resultados mais confiáveis e precisos com maior eficiência.
20

Sistema radicular de cana-de-açúcar e identificação de raízes metabolicamente ativas. / Sugar cane root system and identification of roots with active metabolism.

Carlos Eduardo Faroni 13 January 2005 (has links)
O conhecimento da dinâmica de crescimento das raízes da cana-de-açúcar, bem como da arquitetura de seu sistema radicular, permite melhor compreensão das relações entre a planta e o seu ambiente de produção, possibilitando o manejo a partir de práticas agrícolas mais eficientes e sustentáveis que resultem em aumento de produtividade e longevidade da cultura. O presente estudo teve por objetivo desenvolver um método para determinação da distribuição e do desenvolvimento de raízes metabolicamente ativas de cana-de-açúcar no solo, por meio da técnica da diluição do isótopo 15N, associado aos métodos de amostragem com monólito e sonda amostradora de raízes. O experimento foi realizado em área comercial de cana-de-açúcar na região canavieira de Piracicaba, Estado de São Paulo, em LATOSSOLO VERMELHO distrófico arenoso, com uma segunda rebrota do cultivar RB85 5156. O delineamento experimental foi em blocos subdivididos no tempo, com as amostragens de raízes realizadas a cada 50 a 60 dias de janeiro a junho de 2004. A uréia foi o veículo de fornecimento do marcador isotópico 15N, por meio de solução aplicada às folhas das plantas. Após colheita da parte aérea, realizada 96 horas após a aplicação da solução de uréia, foram abertas trincheiras, transversalmente à linha da cultura, com dimensões de 1 m de comprimento e 1,4 m de largura. Amostras foram colhidas por meio de monólito nas profundidades de 0 a 20, 20 a 40, 40 a 60 e 60 a 80 cm, na projeção da linha da cultura e lateralmente nas distâncias de 14 a 42 cm e de 42 a 70 cm da linha da cultura. Outras amostras foram colhidas com sonda amostradora de raízes, paralelamente à parede interna das trincheiras, a 10 cm de distância do local onde foram retirados os monólitos, nas mesmas profundidades e nas distâncias de 28 e 56 cm da linha. Em cada profundidade de amostragem, e na projeção da linha da cultura, foram separadas amostras de raízes visualmente ativas. Estas amostras forma consideradas padrão para a determinação por diluição isotópica de raízes com metabolismo ativo. As determinações do teor de N e de abundância de 15N em amostras de planta e de solo foram realizadas em um espectrômetro de massas modelo ANCA-SL da Eurapa Scientific Ltda. Os resultados mostraram que o método da diluição isotópica com 15N possibilitou avaliar a massa de raízes com metabolismo ativo e sua distribuição no solo, e o método de amostragem de raízes com a sonda foi viável em comparação com a amostragem do monólito, nas seguintes condições: na quantificação de raízes nas profundidades de 0 a 20, 20 a 40 e 60 a 80 cm do perfil do solo para raízes totais, e nos 20 cm superficiais do solo, profundidade na qual a massa de raízes foi maior, para raízes metabolicamente ativas. / Knowledge about of sugarcane root growth dynamic, as well as the root system architecture of sugarcane crop allows understanding better the relationships between the plant and its environment. This knowledge is important to define the crop management with most efficiency and using sustainable practices, to increasing both sugarcane crop yield and longevity. The aim of this study was to evaluate a method in order to determine sugarcane roots with active metabolism and its distribution and growth in the soil profile, by using isotopic dilution technique with 15N associated with sampling by monolite and probe. The experiment was conducted in the sugarcane field, on the region of Piracicaba, State of São Paulo, Brazil, by using the second rattoon of the variety RB 85 5156, grown in a Rhodic Hapludox. The experimental design was in randomized blocks, with four replications. The split plot was considered in relation to the time. The 15N tracer was applied in the plants as urea solution. The above ground part of sugarcane plants were harvested 96 hours after urea solution applications, and trenches with one meter of length and 1.4 meter width were opened transversely to sugarcane rows. Samples were taken by monolite in 0-20, 20-40, 40-60 and 60-80 cm of depth in the soil profile in the row projection and horizontally in the distances of 14 to 42 and 42 to 70 cm from the cane row. Samples were taken by probe in a parallel plan with the internal trench wall at 10 cm of distance from the spot where monolites were collected, in the same depths and at 28 and 56 cm from the row. Roots visually assumed as metabolisms active were separated to each sampling depth and to row lateral projection and were considered standards to determine active roots. Determinations of N contents and 15N abundance in both plant and soil were carried on a mass spectrometer model ANCA-SL (Europa Scientific Ltda.). The results showed the isotopic dilution method with 15N allowed the evaluation of active roots mass and the root distribution in the soil. The root sampling method with probe was adequate comparing with root sampling by monolite in trench to quantify roots, in the following conditions: in the soil depths of 0 to 20, 20 to 40 and 60 to 80 cm to total roots; and in the first 20 cm of depth, where the root mass was higher to active roots.

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