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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.
131

Hyperflora

Koenig, Paige Elizabeth 24 June 2020 (has links)
No description available.
132

Estudo da aderência de arames da armadura de tração em conectores de dutos flexíveis / Study of adhesion of tensile armor wiles in connectors for flexible pipelines

Marcelo Badini Daflon 08 September 2010 (has links)
Este projeto tem o objetivo de apresentar o estudo dos arames da armadura de tração que são empregados no transporte de óleo, gás e umbilicais hidráulicos na indústria petrolífera. Este estudo foi desenvolvido sob a necessidade de melhor ancoragem dos arames da armadura de tração de modo a garantir que, mesmo após a ruptura do arame dentro do conector não haverá o escorregamento do mesmo provocando a queda do duto flexível. Assim sendo, foi estabelecido o estudo de aderência da interface dos arames da armadura de tração dos dutos flexíveis. Com os ensaios concluídos se estudou um novo procedimento para o melhoramento de aderência mecânica dos arames com a resina epóxi. Após os ensaios de aderência e adesão concluídos foi realizado ensaio de tração em cada arame da armadura de tração sob sua montagem no conector de extremidade para verificação de carregamento que chegam nos ganchos dos arames da armadura de tração. Os estudos realizados no conector de extremidade de 2,5 demonstram que os ganchos dos arames da armadura de tração são de grande importância para a integridade estrutural do duto flexível, visto que o cone de resina formado dentro do conector não está em contato com toda a área dos arames das armaduras de tração. / This project aims to present the study of tensile armor wires usually employed in the transport of oil, gas and hydraulic umbilicals in the petroleum industry. This study was developed as a need for better anchoring of the tensile armor wires in order to guarantee that even after the rupture of the wire within the connector it will not slip causing the fall of the flexible riser. Thus was established the adhesion study of the interface of the tensile armor wires of the flexible risers. After the end of the tests a new procedure for improving mechanical adhesion between the wires and the epoxy resin was studied. After the end of the adhesion tests tensile test was performed on each wire of the tensile armor under its mounting on the end fitting for checking the loading that reaches the hook of the armor wires. The trials performed in the 2.5end fitting show that the tensile armor wire hooks are of great importance for the structural integrity of the flexible riser, as there is no contact between the resin cone formed within the end fitting and the tensile armor wires area.
133

Estudo da aderência de arames da armadura de tração em conectores de dutos flexíveis / Study of adhesion of tensile armor wiles in connectors for flexible pipelines

Marcelo Badini Daflon 08 September 2010 (has links)
Este projeto tem o objetivo de apresentar o estudo dos arames da armadura de tração que são empregados no transporte de óleo, gás e umbilicais hidráulicos na indústria petrolífera. Este estudo foi desenvolvido sob a necessidade de melhor ancoragem dos arames da armadura de tração de modo a garantir que, mesmo após a ruptura do arame dentro do conector não haverá o escorregamento do mesmo provocando a queda do duto flexível. Assim sendo, foi estabelecido o estudo de aderência da interface dos arames da armadura de tração dos dutos flexíveis. Com os ensaios concluídos se estudou um novo procedimento para o melhoramento de aderência mecânica dos arames com a resina epóxi. Após os ensaios de aderência e adesão concluídos foi realizado ensaio de tração em cada arame da armadura de tração sob sua montagem no conector de extremidade para verificação de carregamento que chegam nos ganchos dos arames da armadura de tração. Os estudos realizados no conector de extremidade de 2,5 demonstram que os ganchos dos arames da armadura de tração são de grande importância para a integridade estrutural do duto flexível, visto que o cone de resina formado dentro do conector não está em contato com toda a área dos arames das armaduras de tração. / This project aims to present the study of tensile armor wires usually employed in the transport of oil, gas and hydraulic umbilicals in the petroleum industry. This study was developed as a need for better anchoring of the tensile armor wires in order to guarantee that even after the rupture of the wire within the connector it will not slip causing the fall of the flexible riser. Thus was established the adhesion study of the interface of the tensile armor wires of the flexible risers. After the end of the tests a new procedure for improving mechanical adhesion between the wires and the epoxy resin was studied. After the end of the adhesion tests tensile test was performed on each wire of the tensile armor under its mounting on the end fitting for checking the loading that reaches the hook of the armor wires. The trials performed in the 2.5end fitting show that the tensile armor wire hooks are of great importance for the structural integrity of the flexible riser, as there is no contact between the resin cone formed within the end fitting and the tensile armor wires area.
134

Contribution à la prédiction du risque lésionnel thoracique lors de chocs localisés à travers la caractérisation et la modélisation d'impacts balistiques non pénétrants / Towards the prediction of thoracic injuries during blunt ballistic impacts through experimental and numerical approaches

Bracq, Anthony 05 July 2018 (has links)
Depuis plusieurs décennies, l’évaluation des armes à létalité réduite (ALR) et des gilets pare-balles suscite l’intérêt majeur des forces de l’ordre autour du globe. En effet, ces armes présumées à létalité réduite ou non létales sont tenues d’occasionner uniquement une douleur suffisamment importante à un individu afin d’assurer sa neutralisation. Les gilets pare-balles, quant à eux, doivent garantir un certain niveau de protection pour réduire le risque de traumatismes lié à leur déformation dynamique. Le Centre de Recherche, d’Expertise et d’appui Logistique (CREL) du Ministère de l’Intérieur français a ainsi pour objectif le développement d’un outil de prédiction du risque lésionnel thoracique lors d’impacts balistiques non pénétrants. Cela permettrait alors d’évaluer les performances des ALR et des gilets pare-balles avant leur déploiement en théâtre d’opérations. Plus précisément, cette méthode doit uniquement être fondée sur la mesure directe du processus dynamique de déformation d’un bloc de gel synthétique soumis à un impact balistique. Pour répondre à ce besoin, l’approche numérique est considérée dans ces travaux de thèse par l’emploi du mannequin numérique du thorax humain HUByx comme un outil intermédiaire permettant la détermination de fonctions de transfert entre les mesures expérimentales sur un bloc de gel et le risque lésionnel. La reproduction de conditions d’impact réelles sur HUByx nécessite la caractérisation et la modélisation de projectiles ALR ainsi que de projectiles d’armes à feu et de gilets pare-balles. Elles reposent sur une procédure d’identification par méthode inverse appliquée à l’essai de Taylor pour la modélisation des ALR et à l’essai du cône dynamique d’enfoncement sur le bloc de gel pour celle du couple projectile/gilet pare-balles. Des travaux sont dédiés à la caractérisation mécanique et à la modélisation du gel synthétique sous sollicitations dynamiques. Enfin, une approche statistique basée sur des analyses de corrélation est introduite exploitant à la fois les mesures expérimentales, les données numériques ainsi que les rapports de cas de la littérature. Une cartographie du thorax associée au risque de fractures costales est établie et est uniquement fonction d’une mesure expérimentale. / For decades, the assessment of less-lethal weapons (LLW) and bulletproof vests has generated major interest from law enforcement agencies around the world. Indeed, these presumed less-lethal or non-lethal weapons are required to cause only significant pain to an individual to ensure their neutralization. Bulletproof vests, in turn, must provide a certain level of protection to reduce the risk of trauma related to their dynamic deformation. The Center for Research, Expertise and Logistics Support (CREL) of the French Ministry of the Interior aims to develop a tool to predict thoracic injury risk during non-penetrating ballistic impacts. It would therefore be possible to evaluate the performance of LLW and bulletproof vests before their deployment in operations. More precisely, this method must only be based on the direct measurement of the dynamic process of deformation of a synthetic gel block subjected to a ballistic impact. To address that issue, the numerical approach is considered in this thesis by the use of the human thorax dummy HUByx as an intermediate tool for the determination of transfer functions between experimental metrics on a gel block and the risk of injury. The reproduction of real impact conditions on HUByx thus requires the characterization and modeling of less-lethal projectiles as well as projectiles of firearms and bulletproof vests. They rely on an inverse method identification procedure applied to the Taylor test for modeling LLW and on the analysis of blunt impacts on the gel block for projectiles/bulletproof vests. Work is then dedicated to the mechanical characterization and modeling of the synthetic gel under dynamic loadings. Finally, a statistical approach based on correlation analyses is introduced using both experimental measurements, numerical data as well as case reports from the literature. A thorax mapping associated with the risk of rib fractures is established and only depends on an experimental metric.
135

Nano-particles In Multi-scale Composites And Ballistic Applications

Gibson, Jason 01 January 2013 (has links)
Carbon nanotubes, graphene and nano sized core shell rubber particles have all been extensively researched for their capability to improve mechanical properties of thermoset resins. However, there has been a lack of research on their evaluation for energy absorption in high velocity impact scenarios, and the fundamental mechanics of their failure mechanisms during highly dynamic stress transfer through the matrix. This fundamental research is essential for laying the foundation for improvement in ballistic performance in composite armor. In hard armor applications, energy absorption is largely accomplished through delamination between plies of the composite laminate. This energy absorption is accomplished through two mechanisms. The first being the elongation of the fiber reinforcement contained in the resin matrix, and the second is the propagation of the crack in between the discreet fabric plies. This research aims to fundamentally study the energy absorption characteristics of various nano-particles as reinforcements in thermoset resin for high velocity impact applications. Multiple morphologies will be evaluated through use of platelet, tubular and spherical shaped nano-particles. Evaluations of the effect on stress transfer through the matrix due to the combination of nano sized and micro scale particles of milled fiber is conducted. Three different nano-particles are utilized, specifically, multi-walled carbon nanotubes, graphene, and core shell rubber particles. The difference in surface area, aspect ratio and molecular structure between the tube, platelet and spherical nano-particles causes energy absorption through different failure mechanisms. This changes the impact performance of composite panels enhanced with the nanoparticle fillers. Composite panels made through the use of dispersing the various nano-particles iv in a non-contact planetary mixer, are evaluated through various dynamic and static testing, including unnotched cantilever beam impact, mixed mode fracture toughness, split-Hopkinson bar, and ballistic V50 testing. The unnotched cantilever beam testing showed that the addition of milled fiber degraded the impact resistance of the samples. Addition of graphene nano platelets unilaterally degraded impact resistance through the unnotched cantilever beam testing. 1.5% loading of MWCNT showed the greatest increase in impact resistance, with a 43% increase over baseline. Determining the critical load for mixed mode interlaminar shear testing can be difficult for composite panels that bend without breaking. An iterative technique of optimizing the coefficient of determination, R2 , in linear regression is developed for objectively determining the point of non-linearity for critical load. This allows for a mathematical method of determination; thereby eliminating any subjective decision of choosing where the data becomes non-linear. The core shell rubber nano particles showed the greatest strain energy release rate with an exponential improvement over the baseline results. Synergistic effects between nano and micro sized particles in the resin matrix during transfer of the stress wave were created and evaluated. Loadings of 1% milled carbon fiber enhanced the V50 ballistic performance of both carbon nanotube and core shell rubber particles in the resin matrix. However, the addition of milled carbon fiber degrades the impact resistance of all nano-particle enhanced resin matrices. Therefore, benefits gained from the addition of microsized particles in combination with nano-sized particles, are only seen in high energy impact scenarios with micro second durations. v Loadings of 1% core shell rubber particles and 1% milled carbon fiber have an improvement of 8% in V50 ballistic performance over the baseline epoxy sample for 44 mag single wad cutter gas check projectiles. Loadings of 1% multi-walled carbon nanotubes with 1% milled carbon fiber have an improvement of 7.3% in V50 ballistic performance over the baseline epoxy sample. The failure mechanism of the various nano-particle enhanced resin matrices during the ballistic event is discussed through the use of scanning electron microscope images and Raman spectroscopy of the panels after failure. The Raman spectroscopy data shows a Raman shift for the fibers that had an enhancement in the V50 performance through the use of nano-particles. The Raman band for Kevlar® centered at 1,649 cm-1 stemming from the stretching of the C==O bond of the fiber shows to be more sensitive to the residual axial strain, while the Raman band centered at 1,611 cm-1 stemming from the C-C phenyl ring is minimally affected for the CSR enhanced panels due to the failure mechanism of the CSR particles during crack propagation.
136

Исследование стратегий преодолевающего поведения в поздней зрелости : магистерская диссертация / Study of strategies for coping behavior in late adulthood

Бакунина, М. Ю., Bakunina, M. Yu. January 2022 (has links)
Цель — исследование стратегий преодолевающего поведения в поздней зрелости у педагогов общеобразовательных школ. Объектом исследования стали педагоги общеобразовательных школ Свердловской области в возрасте поздней зрелости. Предмет исследования — стратегии преодолевающего поведения в поздней зрелости. Магистерская диссертация состоит из введения, двух глав, заключения, списка литературы (113 источников) и приложения, включающего в себя бланки применявшихся методик. Объем магистерской диссертации 88 страниц, на которых размещены 3 рисунков и 6 таблиц. Во введении раскрывается актуальность проблемы исследования, разработанность проблематики, ставятся цель и задачи исследования, определяются объект и предмет исследования, а также этапы проведения исследования, научная новизна, теоретическая и практическая значимость работы, которая должна вылиться в разработку технологии консультирования по выбору стратегий преодолевающего поведения в поздней зрелости. Первая глава представляет собой обзор иностранной и отечественной литературы, содержащие теоретические аспекты исследования преодолевающего поведения в поздней зрелости. Представлены разделы, посвященные исследованию психологических особенностей людей в поздней зрелости и двум типам механизмов – психологической защите и стратегиям преодолевающего поведения. Выводы по первой главе представляют собой итоги по изучению теоретического материала. Подчеркивается важность психологических консультаций для людей в поздней зрелости, важность разговоров с ними о том, что существуют разные стратегии преодоления сложных случаев и проблем. Вторая глава посвящена эмпирической части исследования – опытно-поисковому исследованию стратегий преодолевающего поведения в поздней старости. В ней представлено описание организации и методик проведенного исследования и результатов, полученных по всем использованным методикам. Анализ уровня проявления механизмов психологической защиты проходил при помощи опросника Плутчика — Келлермана — Конте (LifeStyle Index). Для диагностического инструментария и исследования превалирующих стратегий преодолевающего поведения применялся опросник Стивена Хобфолла (Hobfoll) «Стратегии преодоления стрессовых ситуаций» (чаще всего именуется «Опросник SACS»), в основе которого лежит теория многоосевой модели поведения преодоления. В главе представлены результаты исследования. В качестве выводов предлагается практическая модель психологического консультирования в поздней зрелости. В заключении в обобщенном виде изложены результаты теоретической и эмпирической частей работы, обоснована практическая значимость исследования. Предложены пути и способы преодоления кризисного этапа в развитии личности в поздней зрелости с опорой на психотехнологии. / The goal is to study the strategies of overcoming behavior in late adulthood among teachers of secondary schools. The object of the study was teachers of secondary schools in the Sverdlovsk region at the age of late maturity. The subject of the research is the strategy of overcoming behavior in late adulthood. The master's thesis consists of an introduction, two chapters, a conclusion, a list of references (113 sources) and an appendix, which includes forms of the methods used. The volume of the master's thesis is 88 pages, which contain 3 figures and 6 tables. The introduction reveals the relevance of the research problem, the development of the problematics, sets the goal and objectives of the research, defines the object and subject of the research, as well as the stages of the research, scientific novelty, theoretical and practical significance of the work, which should result in the development of a technology for consulting on the choice of strategies for overcoming behavior in late maturity. The first chapter is a review of foreign and domestic literature, containing theoretical aspects of the study of overcoming behavior in late adulthood. Sections are presented devoted to the study of the psychological characteristics of people in late adulthood and two types of mechanisms - psychological defense and strategies for overcoming behavior. The conclusions on the first chapter are the results of the study of theoretical material. The importance of psychological counseling for people in late adulthood is emphasized, the importance of talking with them about the fact that there are different strategies for overcoming difficult cases and problems. The second chapter is devoted to the empirical part of the study - an experimental and exploratory study of strategies for overcoming behavior in late old age. It presents a description of the organization and methods of the study and the results obtained by all methods used. Analysis of the level of manifestation of psychological defense mechanisms was carried out using the Plutchik-Kellerman-Conte questionnaire (LifeStyle Index). For diagnostic tools and the study of prevailing coping behavior strategies, Stephen Hobfoll's Stress Coping Strategies questionnaire (most commonly referred to as the SACS Questionnaire) was used, which is based on the theory of a multi-axis model of coping behavior. The chapter presents the results of the study. As conclusions, a practical model of psychological counseling in late adulthood is proposed. In conclusion, the results of the theoretical and empirical parts of the work are summarized, and the practical significance of the study is substantiated. The ways and means of overcoming the crisis stage in the development of personality in late maturity based on psychotechnologies are proposed.

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