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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.
381

Long-term distribution network pricing and planning to facilitate efficient power distribution

Heng, Hui Yi January 2010 (has links)
No description available.
382

Comparações de populações discretas / Comparison of discrete populations

Watanabe, Alexandre Hiroshi 19 April 2013 (has links)
Um dos principais problemas em testes de hipóteses para a homogeneidade de curvas de sobrevivência ocorre quando as taxas de falha (ou funções de intensidade) não são proporcionais. Apesar do teste de Log-rank ser o teste não paramétrico mais utilizado para se comparar duas ou mais populações sujeitas a dados censurados, este teste apresentada duas restrições. Primeiro, toda a teoria assintótica envolvida com o teste de Log-rank, tem como hipótese o fato das populações envolvidas terem distribuições contínuas ou no máximo mistas. Segundo, o teste de Log-rank não apresenta bom comportamento quando as funções intensidade cruzam. O ponto inicial para análise consiste em assumir que os dados são contínuos e neste caso processos Gaussianos apropriados podem ser utilizados para testar a hipótese de homogeneidade. Aqui, citamos o teste de Renyi e Cramér-von Mises para dados contínuos (CCVM), ver Klein e Moeschberger (1997) [15]. Apesar destes testes não paramétricos apresentar bons resultados para dados contínuos, esses podem ter problemas para dados discretos ou arredondados. Neste trabalho, fazemos um estudo simulação da estatística de Cramér von-Mises (CVM) proposto por Leão e Ohashi [16], que nos permite detectar taxas de falha não proporcionais (cruzamento das taxas de falha) sujeitas a censuras arbitrárias para dados discretos ou arredondados. Propomos também, uma modificação no teste de Log-rank clássico para dados dispostos em uma tabela de contingência. Ao aplicarmos as estatísticas propostas neste trabalho para dados discretos ou arredondados, o teste desenvolvido apresenta uma função poder melhor do que os testes usuais / One of the main problems in hypothesis testing for homogeneity of survival curves occurs when the failure rate (or intensity functions) are nonproportional. Although the Log-rank test is a nonparametric test most commonly used to compare two or more populations subject to censored data, this test presented two constraints. First, all the asymptotic theory involved with the Log-rank test, is the hypothesis that individuals and populations involved have continuous distributions or at best mixed. Second, the log-rank test does not show well when the intensity functions intersect. The starting point for the analysis is to assume that the data is continuous and in this case suitable Gaussian processes may be used to test the assumption of homogeneity. Here, we cite the Renyi test and Cramér-von Mises for continuous data (CCVM), and Moeschberger see Klein (1997) [15]. Despite these non-parametric tests show good results for continuous data, these may have trouble discrete data or rounded. In this work, we perform a simulation study of statistic Cramér-von Mises (CVM) proposed by Leão and Ohashi [16], which allows us to detect failure rates are nonproportional (crossing of failure rates) subject to censure for arbitrary data discrete or rounded. We also propose a modification of the test log-rank classic data arranged in a contingency table. By applying the statistics proposed in this paper for discrete or rounded data, developed the test shows a power function better than the usual testing
383

Economic analysis of marine industrial fisheries

Torres, Julio Alejandro Pena January 1996 (has links)
This thesis is a collection of essays on the problem of overfishing in multifirm fisheries with a common property fish stock. We focus on the case of marine industrial fisheries, where the costs of preventing free riding tend to preclude cooperative harvesting. We study the overfishing problem by analysing harvesting incentives that stem from variations in (i) technological (cost, production and biological growth) functions, (ii) institutional factors (access schemes, regulatory agencies' instruments and their monitoring and enforcement powers, harvesting competition), and (iii) objective functions (private firms' planning horizons, welfare functions). Chapter 2 discusses conditions under which a fishing collapse can occur and examines the commonly held argument that fishing collapse is a public bad. Chapter 3 studies Chilean fishing regulations over the last five decades. The regulator's persistent inability to enforce annual quotas is analysed. Distributive disputes and triggered lobbying powers are examined. The late 1980s controversies over a new Chilean fishing law are analysed in-depth from this perspective. Chapter 4 explains the main motivations and key assumptions leading us to the oligopoly harvesting models of chapters 5 (static setting) and 6 (dynamic setting). These models focus on a deterministic single fish species and a single sector harvesting fishery composed of profit maximizing and price taking private firms that compete with each other by following non-cooperative harvesting strategies. These models examine the overfishing rankings that result from comparing Cournot-Nash and Stackelberg equilibria. First best and second best welfare benchmarks are considered. The Cournot-Nash setting is intended to illustrate a large number oligopolistic fishery, while the Stackelberg equilibrium is meant to be a first approximation to analyse the implications of harvesting fisheries subject to industrial concentration. Empirical evidence suggesting the presence of industrial concentration in a series of important marine industrial fisheries is described in chapters 3 and 4.
384

Designing communication devices for long distance dating relationships

Gooch, Daniel January 2014 (has links)
This thesis investigates the design and use of communication technologies to support long distance dating relationships (LDDRs). We focus on using co-located behaviours that hold special relational meaning as the metaphor behind the design of devices to mediate between separated partners. Social Presence is used as the main theoretical construct through which support for LDDRs is addressed. Social Presence is a phenomenological concept which refers to “the degree of salience of the other person in the interaction and the consequent salience of the interpersonal relationship” [Short et al., 1976, p. 65]. An additional concept, Closeness, is also brought in to the design problem to account for the supportive role of communication technologies between moments of synchronous contact. This thesis proposes three main arguments. The first is that individual acts of communication, through feelings of Social Presence, have an impact on a couple’s feelings of Closeness towards one another. We explore possible connections between Social Presence and Closeness through a diary study. The results of the diary study also establish that the selection of communication media impacts feelings of Social Presence. Our second argument is that a number of design facets, explored throughout the thesis, could enhance the design of communication technologies for LDDRs by increasing feelings of Social Presence. An analysis of current literature informs the development of seven prototype devices based on hand-holding, hugging, sharing notes and pillow talk. Two interview studies explore people’s reactions to these devices. The findings from these studies are integrated into a design space which describes some of the design decisions that should be considered when creating behaviour-based devices which aim to support LDDRs. Our third argument is that devices based on co-located behaviours support LDDRs through engendering high levels of SP. This is investigated through five case studies using the devices we previously developed, showing that three of our devices are associated with particularly high levels of SP. They also provide insights about the design space facets, as realised in the devices, through using the devices within couples’ existing communication routines. The thesis concludes with a discussion of how the results of these studies are of relevance to researchers interested in supporting long distance dating relationships. Our investigation into Social Presence provides two main contributions; firstly it offers an understanding of how various factors (including relationship type and distance) affect feelings of SP. Secondly, it demonstrates that increasing feelings of Social Presence can have a longer-term impact on LDDRs through increasing their feelings of Closeness towards one another. This suggests that SP is suitable concept to try and support through the design of communication technologies. In addition to informing our discussion of our design space, the case studies within this thesis highlight that devices based on co-located behaviours can help support LDDRs. Given the dearth of devices based on this metaphor, we suggest that other researchers may be interested in extending these findings by exploring other behavioural metaphors. The design space proposed within this thesis offers two main contributions. Firstly, designers can use the design space to foster innovation when creating new designs. Design spaces result in a descriptive and exploratory tool for designers creating new innovations. Secondly, the comprehensive consideration of the various dimensions, especially regarding our consideration of existing communication technologies, provides researchers with a novel design-centric view over the state of the art.
385

Lessons after Barbauld : the conversational primer in late-eighteenth-century Britain

Lim, Jessica Wen Hui January 2019 (has links)
This thesis explores how Anna Letitia Barbauld's book Lessons for Children Aged Two to Three Years (1778) facilitated the development of the conversational primer. This genre, which has not yet been theorised, may be identified by the way the texts present themselves as verisimilar and replicable sets of conversations, and depict parent-teachers and child-pupils as companions. This genre challenges the idea that there is a dichotomy between 'adult' and 'child' readers, a concept that inflects many contemporary approaches to children's literature studies. Through a close reading of Lessons for Children and subsequent conversational primers, this thesis suggests that Barbauld's Rational Dissenting value of discursive diversity influenced British middle-class children's culture, enabling the voices of verisimilar children to proliferate children's books on a previously unknown scale. The Introduction establishes ways in which concepts of child-parent relationships were used as paradigms for understanding modes of government in eighteenth-century Britain. Chapter One examines how children's books prior to Lessons for Children addressed different types of implied child readers with the aim of producing members of an ideal society. Chapter Two explores how Barbauld created a space in which parents could participate in the children's literature market through her introduction of the parent-author as a literary trope, her portrayals of verisimilar mother-child interactions in accessible, domestic spaces. Chapter Three charts how Lessons for Children became the prototype from which subsequent conversational primers drew their literary identity. The fourth chapter contextualises Lessons for Children as an expression of Barbauld's Rational Dissent, and posits that the rise of the conversational primer is indicative of the influence of Rational Dissenting values upon British middle-class children's culture. Chapter Five contrasts the afterlife of the conversational primer with children's books that generated readers' imaginative identification with characters. This comparison suggests that conversational primers encapsulated middle-class Georgian ideals regarding familial learning; an historical specificity that is, in part, responsible for the genre's popular demise. This thesis studies the lifecycle of the conversational primer in the British children's literature market. It examines the porousness between paratextual materials and texts, and shows how an individual author stimulated generic development by popularising specific literary tropes. By theorising the genre of the conversational primer, this study provides a new and productive discourse concerning adult-child interactions in children's literature.
386

Hospitals to celebrate living : a therapeutic environment for long term care

Stohlman, Thomas Joseph January 1978 (has links)
Thesis. 1978. M.Arch--Massachusetts Institute of Technology. Dept. of Architecture. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH. / Bibliography: leaves 83-84. / by Thomas Joseph Stohlman, Jr. / M.Arch
387

Análise da expressão de RNAs longos não-codificadores em linhagens celulares de melanoma em diferentes estágios de progressão tumoral / Analysis of long noncoding RNAs expression in melanoma cell lines at different stages of tumor progression

Siena, Ádamo Davi Diógenes 03 June 2016 (has links)
Evidências sugerem que somente cerca de 2% do genoma codifica proteínas, mas que a maior parte dos 80% restante possui atividade transcricional. Por não ser codificadora de proteínas, essa fração do genoma foi considerada como \'DNA lixo\'. Entretanto, estudos mais recentes e análises pós-ENCODE vem demonstrando que parte significativa destes RNAs não-codificantes desempenham papéis importantes em processos biológicos essenciais e também em doenças. Os RNAs longos não codificadores (lncRNAs) embora tradicionalmente conhecidos pelo imprintinggenômico, vem demonstrando diversos mecanismos de regulação da expressão gênica, principalmente emnível pós transcricional. Um destes lncRNAs que está envolvido principalmente com a metastase em câncer é o HOTAIR. O melanoma tem sido utilizado como modelo de progressao do câncer por suas etapas bem definidas e por isso já tem apresentado alguns lncRNAs envolvidos na melanomagenese e progressão do melanoma, tal como o HOTAIR. Assim, neste trabalho foi analisado a expressão de lncRNAs de amostras de melanócito e melanoma, sendo que as amostras malignas representam as principais fases de progressão deste tipo de câncer. Foram analisados os níveis de expressão relativa. Além disso, foi realizado a expressão diferencial dos grupos representativos do melanoma. Foram encontrados lncRNAs com valores de expressão e significância (p-ajustado <0,01 e fold change >1) que podem ser indicativos de expressão associada a progressão do melanoma. Os lncRNAs mais diferencialmente expressos foram avaliados quanto a sua capacidade de interação proteína-RNA e literatura científica disponível e então foram selecionados para posteriores ensaios funcionais. / Evidence suggests that only about 2% of the genome encodes protein, but most remaining 80% has transcriptional activity. Since they do not coding for proteins, this fraction of the genome was considered \'junk DNA\', However, recent studies and post-ENCODE analisys has shown that significant part of these non-coding RNAs play important roles in essential biological processes and in disease. Long noncoding RNAs (lncRNAs) although traditionally known for genomic imprinting, has demonstrated several mechanisms of regulation of gene expression, especially at the post transcriptional level. One of these lncRNAs that is involved primarily with metastasis in câncer is HOTAIR. Melanoma has been used as a model of câncer progression by its well-defined steps, and so it has been presented some lncRNAs involved in melanoma progression and melanomagenese, as HOTAIR was demonstrated. In this work it was analyzed the expression of lncRNAs of melanocyte and melanoma samples, and malignant samples represent the main stages of progression of this type of câncer. Relative expression levels were analyzed. Furthermore, it was performed differential expression of representative melanoma groups. lncRNAs found with expression values and significance (p-adjusted <0.01 and fold change> 1) may be indicative of expression associated with melanoma progression. The lncRNAs more differentially expressed were evaluated for their ability to interact protein-RNA and available scientific literature and then were selected for further functional assays.
388

Ethanol modulation of NMDA receptors and NMDAr-dependent long-term depression in the developing juvenile dentate gyrus

Sawchuk, Scott D. 01 May 2019 (has links)
Long-term depression (LTD) induced by low frequency stimulation (LFS; 900x1Hz) at medial perforant path (MPP) synapses in the rat dentate gyrus (DG) has been described as both developmentally regulated and N-methyl D-aspartate receptor (NMDAr) independent, yet sufficient evidence suggest that the processes is not entirely independent of NMDAr activity. In the present study, in vitro DG-LTD LFS was induced in hippocampal slices prepared from rats at postnatal day (PND) 14, 21 and 28 to investigate how the sensitivity of DG-LTD~LFS to the NMDAr antagonist amino-5-phosphonovaleric acid (AP5; 50µM) changes throughout the juvenile developmental period (jDP; PNDs 12-29) that occurs immediately after the period of peak neurogenesis. We further examined the acute effects of the partial NMDAr antagonist ethanol (EtOH) on DG-LTD LFS and NMDAr excitatory post synaptic currents (NMDAr-EPSCs) in dentate granule cells (DGCs) using 50 and 100mM concentrations (50mM ~0.2%BAC) of EtOH. The magnitude of LTD induced at all three time points was not statistically different between age groups, but the probability of successfully inducing LTD did decrease with age. We found that AP5 was insufficient to inhibit DG-LTD LFS at PND14, but significantly inhibited DG-LTD LFS at PND21 and PND28. We also found that 50mM EtOH, but not 100mM EtOH, significantly attenuated the mag-nitude of DG-LTD LFS induced at each time point. Acute effects of 50mM EtOH had relatively little effect on NMDAr-EPSCs at PND14, and showed a slight potentiation of the response at PND21. 50mM EtOH at PND28, and 100mM EtOH at all three developmental time points showed inhibition of the NMDAr-EPSC. These findings provide insight on how developmental changes to the DG network and dentate gran-ule cells (DGCs) influences mechanisms and processes involved in the induction and expression of synaptic plasticity in the DG. / Graduate
389

Tuftade golvsmycken och prydnadskuddar / Tufted floor jewelleries and decorative cushions

Jönsson, Ida January 2005 (has links)
This work is about getting to know tufting as a technique and to design tufted products for home furnishing. It all began in Finland, where during springtime 2004, I got in contact with the technique of tufting for the first time. A very pleasant meeting that resulted in two carpets and a longing to continue and learn more. It was then that an idea for my final project started to take form. My wish was to design tufted “floor jewelleries” and cushions. I made a base for my project during a design project in autumn 2004. During a stay in New York I got inspired partly from colours and shapes from the Bauhaus movement, partly from the architecture of the city. The geometric forms associated to Bauhaus spoke to me. In New York I got fascinated of the lines and surfaces next to each other on the front of the buildings. The small details were important to the entire impression. The amazing perspectives were also very inspiring. It was a great feeling glancing up buildings that had no end and above all looking down on the top of the buildings and on the streets from the top of Empire state building. The collected material from the design project was then put together with impressions of Swedish nature. So I got the inspiration material that had feeling that was hard, soft, warm, cold, powerful, and fragile. Those emotions have been important to ad to the tufted carpets. Wool was chosen to give the felling of warmth and linen to ad shine. The smooth materials made a nice complement to the strict geometric forms. The group of tufted products contain one big pillow for the floor, seven decorative cushions and four carpets. The pillow for the floor becomes a plain and soft piece of furniture, strict in black and white. The decorative cushion is more colourful and finds its place on a sofa or armchair. The carpets are small and easy to place as “jewelleries” next to or in front of a piece of furniture, on their own, several together, but never with furniture on top. The tufted products fit in both small and big rooms. The little scale makes it easy to change and intensify the expression in a home environment. Through my choice of material I want to give the products a long lifetime. This partly has been a part of the esthetical expression. I have also considered nearby production and ecological alternatives in my choices of materials. A timeless form and colour scale makes the products stand outside trends. That gives the products sustainability and they can be a part of the home for a very long time. The carpets are industrially tufted at Hitex and the cushions are made by me, tufted by hand at Konstnärernas Kollektivverkstad in Gothenburg. An important part of the work was to tuft myself and get a feeling for all the possibilities in that specific technique. / <p>Program: Textildesignutbildningen</p><p>Uppsatsnivå: C</p>
390

Análise de defeitos superficiais com origem no processo de laminação de aços especiais para a cadeia automotiva e implementação de soluções / Analysis of surface defects origanated on the rolling process of automotive steels and implementation of solutions

Viana, Márcio Costa January 2009 (has links)
Diversos tipos de defeitos superficiais estão presentes em barras laminadas (e produtos longos) e a presença destes defeitos pode ser muito prejudicial ao desempenho de peças, principalmente, quando se trata de aços para aplicação na cadeia automotiva, onde os níveis de exigência durante o forjamento da peça e durante a sua aplicação são extremamente elevados. Neste trabalho buscou-se determinar as condições operacionais mais apropriadas para a melhoria da qualidade superficial do produto laminado bruto com conseqüente redução de refugo e retrabalho ao longo de toda a cadeia de produção. O objetivo do trabalho é mostrar os defeitos de superficiais de dobra e escama como conseqüência de condições operacionais inapropriadas. Para isto aplicou-se uma metodologia que envolve a análise dos principais pontos de geração de defeitos, possibilitando um levantamento das causas. Com as ações propostas, buscou-se tornar o processo mais estável. Obtiveram-se melhorias significativas na qualidade superficial do material com acentuada redução no refugo por qualidade de aço produzido. / Several types of defects are present in rolled bars and their effects can be very harmful to the performance of mechanical parts, especially in the case of steels for application in the automotive industry, where quality requirements during forging and during its application are high. In this study we sought to determine the most appropriate operating conditions for the reduction of scrap caused by defects that originate in the rolling process, the analyzed defects were the so called overlap of rolling, scales and risks. For this a methodology that involved the analysis of the main points of generation of defects, allowing a survey of the causes was applied. With the proposed actions it was aimed at making the process more stable. This led to a significant improvement in surface quality of the material with marked reduction in scrap for each kind of steel.

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