abstract: The U.S. Navy is interested in evaluating the dielectric performance of SF6 at 30 kHz in order to develop optimal bushing designs and to ensure reliable operation for the Very Low Frequency/ Low Frequency (VLF/LF) transmitting stations. The breakdown experiments of compressed SF6 at 30 kHz in the pressure range of 1-5 atm were conducted in both the uniform field (plane-plane gap) and the non-uniform field (rod-plane gap). To understand the impact of pressure on the breakdown voltage of SF6 at VLF/LF, empirical models of the dielectric strength of SF6 were derived based on the experimental data and regression analysis. The pressure correction factors that present the correlation between the breakdown voltage of SF6 at VLF/LF and that of air at 50/60 Hz were calculated. These empirical models provide an effective way to use the extensively documented breakdown voltage data of air at 60 Hz to evaluate the dielectric performance of SF6 for the design of VLF/LF high voltage equipment. In addition, several breakdown experiments and similar regression analysis of air at 30 kHz were conducted as well. A ratio of the breakdown voltage of SF6 to that of air at VLF/LF was calculated, from which a significant difference between the uniform gap and the non-uniform gap was observed. All the models and values provide useful information to evaluate and predict the performance of the bushings in practice. / Dissertation/Thesis / M.S. Electrical Engineering 2010

Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第14145号 / 工博第2979号 / 新制||工||1442(附属図書館) / 26451 / UT51-2008-N462 / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 北村 隆一, 教授 谷口 栄一, 教授 小林 潔司 / 学位規則第4条第1項該当

This study was an investigation of the phenomenon of dementia caregiving burden and breakdown in community caregiving situations. 109 carer subjects participated in the study, with 91 current carers - 17 via face-to-face interview and 74 via the internet, and 18 past carers - two via face-to-face interview and 16 via the internet, contributing their experiences of dementia caregiving. Two new carers' assessment tools were devised to meet more fully the requirements of the 'Carers (Recognition and Services) Act 1995' (DoH, 1995), namely the 'Dementia Caregiving Problems Questionnaire (DCPQ)' and 'Dementia Caregiving Burden Questionnaire (DCBQ)'. These new assessments were tested and demonstrated to be reliable, with Cronbach Alpha scores of 0.7029 and 0.8430 respectively, and are recommended for implementation in clinical practice. The key predictive risk factors for high caregiving burden in this study were perceived stress; omission of caregiving satisfactions; carer depression; perceived impact on quality of life; perceived helpfulness of community care services; behaviour problems - especially shouting, swearing and screaming, irritability and night disturbance; poor quality carer/dependant relationship; mood problems; perceived helpfulness of informal support; perceived impact of caregiving on dependant emotional well-being and, to a lesser extent, hours spent in caregiving. The key predictive risk factors for expected relinquishment of home caregiving were DCBQ score; perceived impact on quality of life; perceived stress; carer depression and, to a lesser extent, geographical distance in caregiving; perceived helpfulness of community care services and omission of positive feelings in the carer. Based on the above risk factors, a new 'Dementia Caregiving Breakdown Risk Assessment Tool (DCBRAT)' is proposed for use by community care managers to identify 'at risk' caregiving situations so that service interventions can be targetted more towards carers who are highly burdened in their role, who are at risk of developing psychological health problems or who may be nearing breakdown in their caregiving situation. Thus the effectiveness of service interventions may be maximised and optimal health gain for carers achieved, resulting in improved outcomes for people with dementia. The DCBRAT and the similarly proposed 'Conceptual Model of Dementia Caregiving, Burden and Breakdown' will need to be further tested in post-doctoral research.

Esta dissertação tem por objetivo apresentar a evolução histórica e teórica do debate marxista acerca da relação entre as crises econômicas e o denominado “colapso” do modo de produção capitalista. Um debate que pode referido sob o nome de “controvérsia do colapso” e que esteve ligado ao surgimento e desenvolvimento das principais teorias marxistas de crise. Pretende-se explicitar os argumentos levantados ao longo da controvérsia para, posteriormente, efetuar uma avaliação crítica das diversas posições teóricas assumidas ao longo do debate. Para tanto, a exposição histórica da controvérsia será dividida em três “confrontos”, compreendendo a polêmica inicial em torno da obra revisionista de Eduard Bernstein, o debate sobre os esquemas de reprodução e a discussão acerca da taxa de lucro. Espera-se formar o quadro amplo de uma contenda histórico-teórica que atravessou a economia marxista desde praticamente seu início, destacando, na medida do possível, os autores mais influentes ou originais. Em especial, o presente trabalho é entendido como uma forma de retomar a importância de se pensar a relação entre a (re)produção capitalista, com sua crises internas, e seu fim como formação histórica. / This dissertation aims to present the historical and theoretical evolution of Marxist debate about the relationship between economic crises and the so-called "breakdown" of the capitalist mode of production. A debate that is called “the collapse controversy", and that was linked to the emergence and development of the main Marxist theories of crisis. It is intended to clarify the arguments raised along the controversy to then make a critical evaluation of the various theoretical positions taken in the debate. Therefore, the historical exposition of the controversy will be divided into three "clashes ", comprising the initial controversy surrounding the work of revisionist Eduard Bernstein, the debate on the schemes of reproduction and the discussion about the rate of profit. We expect to present the broad framework of a historical-theoretical contention that crossed the Marxist economics since almost its beginning, highlighting the most influential and original authors. In particular, this work is understood as a way of reasserting the importance of thinking about the relationship between the capitalist (re)production with its internal crises, and its end as a historical formation.

Este trabalho investiga a quebra da aproximação modulacional na interação não-linear de três ondas, a interação do tripleto de ondas. Um modo comum de descrever a interação de três ondas portadoras de alta frequência é a partir da aproximação modulacional, que assume que as amplitudes e fases são lentamente moduladas. Isto apenas é verdade quando o acoplamento entre as três ondas é fraco. Ao se analisar os tipos de dinâmica envolvidas quando o valor do acoplamento é alterado, para grandes valores de acoplamento é detectada uma transição abrupta onde a amplitude limitada do regime modulacional chega a outras regiões do espaço configuracional. Também é investigado o caso onde uma das ondas do tripleto possuir uma frequência muito menor que as outras duas. / This work investigates the breakdown of the traditional modulation approximation in the three wave nonlinear interactions, the wave triplet interaction. A common way to describe the interaction of three high-frequency carriers is by the modulacional approximation, which assume that amplitude and phases are slowly modulated. This is only accurate when the three-wave coupling is weak. When analyzing the different types of dynamics when the coupling is changed, for large values of coupling it is detected an abrupt transition where the limited amplitude of the modulacional region reaches to other regions of the configuration space. It is also investigated the case where one of the waves of the triplet has a much lower frequency than the other two.

Made available in DSpace on 2014-10-09T12:55:14Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:00Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Este trabalho investiga a quebra da aproximação modulacional na interação não-linear de três ondas, a interação do tripleto de ondas. Um modo comum de descrever a interação de três ondas portadoras de alta frequência é a partir da aproximação modulacional, que assume que as amplitudes e fases são lentamente moduladas. Isto apenas é verdade quando o acoplamento entre as três ondas é fraco. Ao se analisar os tipos de dinâmica envolvidas quando o valor do acoplamento é alterado, para grandes valores de acoplamento é detectada uma transição abrupta onde a amplitude limitada do regime modulacional chega a outras regiões do espaço configuracional. Também é investigado o caso onde uma das ondas do tripleto possuir uma frequência muito menor que as outras duas. / This work investigates the breakdown of the traditional modulation approximation in the three wave nonlinear interactions, the wave triplet interaction. A common way to describe the interaction of three high-frequency carriers is by the modulacional approximation, which assume that amplitude and phases are slowly modulated. This is only accurate when the three-wave coupling is weak. When analyzing the different types of dynamics when the coupling is changed, for large values of coupling it is detected an abrupt transition where the limited amplitude of the modulacional region reaches to other regions of the configuration space. It is also investigated the case where one of the waves of the triplet has a much lower frequency than the other two.

Esta dissertação tem por objetivo apresentar a evolução histórica e teórica do debate marxista acerca da relação entre as crises econômicas e o denominado “colapso” do modo de produção capitalista. Um debate que pode referido sob o nome de “controvérsia do colapso” e que esteve ligado ao surgimento e desenvolvimento das principais teorias marxistas de crise. Pretende-se explicitar os argumentos levantados ao longo da controvérsia para, posteriormente, efetuar uma avaliação crítica das diversas posições teóricas assumidas ao longo do debate. Para tanto, a exposição histórica da controvérsia será dividida em três “confrontos”, compreendendo a polêmica inicial em torno da obra revisionista de Eduard Bernstein, o debate sobre os esquemas de reprodução e a discussão acerca da taxa de lucro. Espera-se formar o quadro amplo de uma contenda histórico-teórica que atravessou a economia marxista desde praticamente seu início, destacando, na medida do possível, os autores mais influentes ou originais. Em especial, o presente trabalho é entendido como uma forma de retomar a importância de se pensar a relação entre a (re)produção capitalista, com sua crises internas, e seu fim como formação histórica. / This dissertation aims to present the historical and theoretical evolution of Marxist debate about the relationship between economic crises and the so-called "breakdown" of the capitalist mode of production. A debate that is called “the collapse controversy", and that was linked to the emergence and development of the main Marxist theories of crisis. It is intended to clarify the arguments raised along the controversy to then make a critical evaluation of the various theoretical positions taken in the debate. Therefore, the historical exposition of the controversy will be divided into three "clashes ", comprising the initial controversy surrounding the work of revisionist Eduard Bernstein, the debate on the schemes of reproduction and the discussion about the rate of profit. We expect to present the broad framework of a historical-theoretical contention that crossed the Marxist economics since almost its beginning, highlighting the most influential and original authors. In particular, this work is understood as a way of reasserting the importance of thinking about the relationship between the capitalist (re)production with its internal crises, and its end as a historical formation.

abstract: Speciation is the fundamental process that has generated the vast diversity of life on earth. The hallmark of speciation is the evolution of barriers to gene flow. These barriers may reduce gene flow either by keeping incipient species from hybridizing at all (pre-zygotic), or by reducing the fitness of hybrids (post-zygotic). To understand the genetic architecture of these barriers and how they evolve, I studied a genus of wasps that exhibits barriers to gene flow that act both pre- and post-zygotically. Nasonia is a genus of four species of parasitoid wasps that can be hybridized in the laboratory. When two of these species, N. vitripennis and N. giraulti are mated, their offspring suffer, depending on the generation and cross examined, up to 80% mortality during larval development due to incompatible genic interactions between their nuclear and mitochondrial genomes. These species also exhibit pre-zygotic isolation, meaning they are more likely to mate with their own species when given the choice. I examined these two species and their hybrids to determine the genetic and physiological bases of both speciation mechanisms and to understand the evolutionary forces leading to them. I present results that indicate that the oxidative phosphorylation (OXPHOS) pathway, an essential pathway that is responsible for mitochondrial energy generation, is impaired in hybrids of these two species. These results indicate that this impairment is due to the unique evolutionary dynamics of the combined nuclear and mitochondrial origin of this pathway. I also present results showing that, as larvae, these hybrids experience retarded growth linked to the previously observed mortality and I explore possible physiological mechanisms for this. Finally, I show that the pre-mating isolation is due to a change in a single pheromone component in N. vitripennis males, that this change is under simple genetic control, and that it evolved neutrally before being co-opted as a species recognition signal. These results are an important addition to our overall understanding of the mechanisms of speciation and showcase Nasonia as an emerging model for the study of the genetics of speciation. / Dissertation/Thesis / All supplementary files for Joshua D. Gibson Dissertation / Ph.D. Biology 2013

abstract: This thesis focuses on the influence of a grounded back electrode on the breakdown characteristics. The back electrode is an electrode which attaches at the back side of solid insulation. Insulation with grounded back electrode is a common type of insulation which is adopted in many high voltage power devices. While most of the power equipment work under AC voltage, most of the research on back electrode is focused on the DC voltage. Therefore, it is necessary to deeply investigate the influence of the back electrode under AC applied voltage. To investigate the influence of back electrode, the research is separated into two phases, which are the experiment phase and the electric field analysis phase. In the experiments, the breakdown voltages for both with and without back electrode are obtained. The experimental results indicate that the grounded back electrode does have impact on the breakdown characteristics. Then with the breakdown voltage, based on real experiment model, the electric field is analyzed using computer software. From the field simulation result, it is found that the back electrode also influences the electric field distribution. The inter relationship between the electric field and breakdown voltage is the key to explain all the results and phenomena observed during the experiment. Additionally, the influence of insulation barrier on breakdown is also investigated. Compared to the case without ground electrode, inserting a barrier into the gap can more significantly improve breakdown voltage. / Dissertation/Thesis / M.S. Electrical Engineering 2014