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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.
361

Resposta da demanda industrial e sua influência na formação dos preços de curto prazo no mercado de energia elétrica: uma proposta. / Proposal for industrial power demand response mechanism and short term power princing impact.

Fillipe Henrique Neves Soares 20 January 2017 (has links)
Em diversos mercados de energia onde há competição, a formação de preços de energia elétrica no mercado de curto prazo decorre do equilíbrio da oferta e da demanda, onde geradores e grandes consumidores informam, em periodicidade horária ou inferior, as quantidades de energia e preços associados aos quais estão dispostos a produzir e consumir, respectivamente. No Brasil, no entanto, a demanda utilizada no modelo de formação de preço de energia elétrica no curto prazo (PLD) é considerada inelástica em relação ao preço. Por mais que se possam constatar sinais de resposta da demanda frente à volatilidade do PLD, ou ao custo com uso da rede de transmissão e distribuição no período de ponta, não há mecanismo estabelecido para que os consumidores ofertem as quantidades de energia e preços aos quais estão dispostos a reduzir seu consumo. O presente trabalho tem o objetivo de apresentar proposta de alteração no processo de formação de preço no curto prazo de modo a permitir a Oferta da Redução do Consumo (ORC) pelos consumidores industriais. A proposta parte da representação do parque termelétrico atual, que serve de base para o valor da oferta de redução do consumo, as adaptações para introdução da curva de operação para fins de consideração da redução de consumo, bem como metodologia para aferição do montante de energia efetivamente reduzido. Além disso, de modo a apresentar o potencial benefício sistêmico com a introdução da proposta, são apresentadas simulações com a cadeia de modelos de formação de preço atual tendo como base a indústria de alumínio no Brasil. Os cenários de ORC da indústria levam em consideração parâmetros econômicos que asseguram a atratividade do negócio em consonância com o benefício sistêmico de redução do custo de operação. Apresenta-se ainda simulação da operação do ano de 2015 com estimativa do potencial de ORC no Ambiente de Contratação Livre (ACL) onde se constatou reduções de até 25% no Custo Marginal de Operação (CMO) e 16% de redução despacho termelétrico. / In several competitive power markets, short term power price is the result of the balance of supply and demand represented by bid and ask prices and energy quantities. In Brazil, short term power price (PLD) calculated by Newave/Decomp price models consider price-inflexible demand, even though traces of demand response to short term power prices and demand tariffs can be identified. The purpose of this Thesis is the proposal of changes in process of power pricing allowing large energy consumers bid their price to curtail their consumption in substitution of thermal power dispatch. Topics included in proposal are: cost of installed thermal power plants in power system, industrial demand curtail and restart features, and demand response effectiveness appraisal tools. Current power price models were employed on simulations to evaluate system\'s benefits with demand response. From an industrial perspective, accounting measures were basis to convert loss of production in demand-side bidding price in order to keep business profitability. Estimate of demand side bidding potential market in Brazilian free market with simulation of system impact in 2015 with results that reached 25% of Marginal Cost reduction and 16% of Thermal Dispatch reduction.
362

Análise histológica em tecido epitelial sadio de ratos Wistar (in vivo) irradiados com diferentes intensidades do ultra-som / Histological analyses in healthy epithelium tissue irradiated with different ultrasound intensities in Wistar rats in vivo

Bem, Daiane Müller de 12 December 2008 (has links)
A energia ultra-sônica é um dos recursos físicos amplamente utilizado e pesquisado nos tratamentos de fisioterapia e diagnósticos médicos. Sabe-se que diante de uma escassa literatura dos efeitos do ultra-som em tecidos sadios, muitos profissionais fisioterapeutas acabam realizando aplicações infundadas de métodos e parâmetros. O objetivo desta pesquisa foi avaliar possíveis alterações do tecido sadio in vivo de ratos Wistar irradiados com diferentes intensidades, analisando a histologia e morfometria. Foram utilizados 30 ratos da linhagem Wistar, distribuídos aleatoriamente em 5 grupos de 6 animais cada. Foi escolhida a região dorsal do lado direito para tratamento com área de 4 \'CM POT.2\'. O lado esquerdo serviu como controle em todos os grupos. O tratamento foi feito durante 4 dias com 2 minutos de irradiação. Para verificar a intensidade de saída, utilizou-se o dosímetro de precisão antes da aplicação do ultra-som em cada animal. Foi realizada uma análise histológica descritiva e morfometria por meio do software Image Tool. Como resultado pode-se observar um discreto infiltrado inflamatório e adelgaçamento das fibras da derme, principalmente dos grupos irradiados com 1.5 e 2 W/\'CM POT.2\'. Notou-se também um aumento na espessura da epiderme nas amostras dos animais irradiados quando comparado com o controle. Para avaliar os resultados quantitativos, utilizou-se como análise estatística ANOVA \"one way\" e o teste \"pos hoc\" de Tukey com nível de significância p < 0,01. Em 120 medidas da espessura da epiderme obtiveram-se diferenças significativas do grupo controle com os grupos irradiados com (1.0, 1.5 e 2.0 W/\'CM POT.2\'). Concluímos diante dos resultados que houve alterações no tecido sob ação do US nas doses maiores, o que nos alerta para possíveis implicações do uso do US em estética. / The ultrasound (US) energy is one of the resources widely used and researched in both physio-therapist treatment and in medical diagnosis. In front of a scarce literature about the US effects in healthy tissues, many professionals have carried out unfounded applications of methods and parameters. So, the aim of this research was evaluate, through the histology, possible alternations in healthy tissues of Wistar rats in vivo irradiated with different intensity, analyzing the qualitative and quantitative histological slides. We used 30 Wistar rats randomly distributed in 5 groups of animals each. The local chosen for receiving the treatment was the dorsal right side, whose area was 4 \'CM POT.2\'. The left side was used as control of the animal itself for all the groups. The rats underwent the treatment during 4 days exposed to 2 minutes of irradiation. In order to check the energy output, the precision dosimeter was used before US application in each animal. The histological slides were evaluated qualitatively in the microscope and quantitatively through the image tool software. The qualitative result shows a discrete inflammatory process with infiltration and atrophy dermis fibers, mainly in the groups with higher US dosage. In the quantitative aspect, we found epidermis thickness increased in the 1.5 and 2 W/\'CM POT.2\' of US, with statistical difference (ANOVA) compared to control. We conclude that US therapy can be dangerous with high dosage applied in the intact skin.
363

Evaluating Satisfaction and Benefit from Nutrition Counseling from a Registered Dietitian among Head and Neck Cancer Patients Receiving Radiation Therapy.

Watson, Lori E 05 May 2007 (has links)
The purpose of this study was to determine if patients with head or neck cancer receiving radiation were satisfied with the nutrition counseling they were receiving and if they obtained any benefit. Radiation to the head or neck region promotes side effects such as taste changes and chewing and swallowing difficultly that decrease food and fluid intake. A reduction in nutrients leads to weight loss, and weight loss in cancer patients increases the risk of morbidity and morality as well as decreases quality of life. Subjects were recruited from a local cancer treatment facility and a survey was administered. Subjects were found to manage the side effects better after counseling from the registered dietitian, and a minimal amount of weight loss was observed. Registered dietitians when incorporated into a radiation treatment facility can provide an effective nutrition program targeted at reducing weight loss and improving quality of life.
364

Optimized Acid/Base Extraction and Structural Characterization of β-glucan from Saccharomyces Cerevisiae

Asare, Shardrack O 01 May 2015 (has links)
β-glucan is a major component of the fungal cell wall consisting of (1→3)-β linked glucose polymers with (1→6)-β linked side chains. The published classical isolation procedure of β-glucan from Saccharomyces cerevisiae is expensive and time-consuming. Thus, the aim of this research was to develop an effective procedure for the extraction of glucans. We have developed a new method for glucan extraction that will be cost effective and will maintain the native structure of the glucan. The method that we developed is 80% faster and utilizes 1/3 of the reagents compared to the published classical method. Further, the method developed increases the yield from 2.9 % to 10.3 %. Our new process has a branching frequency of 18.4 down from 197 and a side chain of 5.1 up from 2.5. The data indicate a more preserved native structure of isolated glucans.
365

High-throughput prediction and analysis of drug-protein interactions in the druggable human proteome

Wang, Chen 01 January 2018 (has links)
Drugs exert their (therapeutic) effects via molecular-level interactions with proteins and other biomolecules. Computational prediction of drug-protein interactions plays a significant role in the effort to improve our current and limited knowledge of these interactions. The use of the putative drug-protein interactions could facilitate the discovery of novel applications of drugs, assist in cataloging their targets, and help to explain the details of medicinal efficacy and side-effects of drugs. We investigate current studies related to the computational prediction of drug-protein interactions and categorize them into protein structure-based and similarity-based methods. We evaluate three representative structure-based predictors and develop a Protein-Drug Interaction Database (PDID) that includes the putative drug targets generated by these three methods for the entire structural human proteome. To address the fact that only a limited set of proteins has known structures, we study the similarity-based methods that do not require this information. We review a comprehensive set of 35 high-impact similarity-based predictors and develop a novel, high-quality benchmark database. We group these predictors based on three types of similarities and their combinations that they use. We discuss and compare key architectural aspects of these methods including their source databases, internal databases and predictive models. Using our novel benchmark database, we perform comparative empirical analysis of predictive performance of seven types of representative predictors that utilize each type of similarity individually or in all possible combinations. We assess predictive quality at the database-wide drug-protein interaction level and we are the first to also include evaluation across individual drugs. Our comprehensive analysis shows that predictors that use more similarity types outperform methods that employ fewer similarities, and that the model combining all three types of similarities secures AUC of 0.93. We offer a first-of-its-kind analysis of sensitivity of predictive performance to intrinsic and extrinsic characteristics of the considered predictors. We find that predictive performance is sensitive to low levels of similarities between sequences of the drug targets and several extrinsic properties of the input drug structures, drug profiles and drug targets.
366

Load Scheduling with Maximum Demand and Time of Use pricing for Microgrids

ALWAN, HAYDER O 01 January 2019 (has links)
Several demand side management (DSM) techniques and algorithms have been used in the literature. These algorithms show that by adopting DSM and Time-of-Use (TOU) price tariffs; electricity cost significantly decreases, and optimal load scheduling is achieved. However, the purpose of the DSM is to not only lower the electricity cost, but also to avoid the peak load even if the electricity prices low. To address this concern, this dissertation starts with a brief literature review on the existing DSM algorithms and schemes. These algorithms can be suitable for Direct Load Control (DLC) schemes, Demand Response (DR), and load scheduling strategies. \end{abstract} Secondly, the dissertations compares two of DSM algorithms to show the performance based on cost minimization, voltage fluctuation, and system power loss [see in Chapter 5]. The results show the importance of balance between objectives such as electricity cost minimization, peak load occurrence, and voltage fluctuation evolution while simultaneously optimizing the cost.
367

Análise do impacto da adesão da tarifa branca em redes de distribuição de energia elétrica considerando a otimização da curva de carga pelo lado do consumidor /

Rosa, Denis Rodrigo. January 2019 (has links)
Orientador: Fábio Leão Bertequini / Resumo: O consumo de energia elétrica por parte de consumidores residenciais apresenta curvas de carga bem definidas ao longo do dia e por meio delas é possível perceber horários de maior e menor concentração de demanda. Consequentemente este comportamento exige muito dos sistemas de geração e distribuição em determinados intervalos de tempo e as concessionárias, por sua vez, tomam medidas para incentivar o consumo em momentos fora destes intervalos. Esta prática é denominada Gerenciamento pelo Lado da Demanda, que pode ocorrer de forma Direta ou Indireta. Uma das formas de Gerenciamento pelo Lado da Demanda Indireto (GLDI), que atualmente vigora no Brasil, é a Tarifa Branca (TB). O objetivo consiste em deslocar a demanda de ponta para horários fora de ponta, contribuindo, assim, para a melhoria da curva de carga do alimentador e, além disto, incentiva a mudança de hábito dos consumidores. Por outro lado, a adoção da TB e a mudança dos hábitos de consumo dos consumidores poderão causar impactos na rede de distribuição os quais devem ser investigados. A proposta deste trabalho é analisar esses impactos, com base em um modelo de Programação Linear Inteira Mista o qual considera a adoção de painéis solares pelo consumidor e, consequentemente, a exportação de energia elétrica para a rede. O modelo busca a otimização da curva de carga do consumidor rearranjando os horários de uso dos aparelhos eletrodomésticos para os horários fora de ponta, levando em conta o conforto e a redução da fatu... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The consumption of electric energy by residential consumers presents well-defined load curves throughout the day through which is possible to perceive times of higher and lower demand concentration. Consequently, this behavior puts a high demand to Generation and Distribution Systems during certain given intervals of time so distributers, in turn, take measures to encourage consumption at moments outside those time ranges. Such practice is known as Demand-Side Management (DSM), which can occur either directly or indirectly. One of the indirect Demand-side Management that takes place in Brazil is called the “White Fee”. Its main objective is to shift peak demand to off-peak hours, contributing to the improvement of the feeder’s load curve and also to encourage consumers’ change of habits. On the other hand, the accession of the White-Tariff and the change of consumer behavior can impact on the distribution grids, which should be looked into. The proposal of this paper is to analyze such impacts based on a Mixed Integer Linear Programming model which considers the consumers’ solar panels purchase, and consequently, energy exports to the grid. The model seeks the enhancement of the consumers’ load curve by rearranging the hours of use household appliances at offpeak hours, taking into account comfort and a decrease in consumers electricity billing. The model was implemented in the AMPL language, making it possible to solve the CPLEX. In order to observe the impact of the White T... (Complete abstract click electronic access below) / Mestre
368

Natural and Anthropogenic Effects on Life History Characteristics in the Side-blotched Lizard (Uta stansburiana)

Smith, Geoffrey David Stuart 01 August 2017 (has links)
Survival is a prerequisite for successful reproduction, and is thus intertwined with fitness. Some physiological systems can improve survival, like the immune system, but compete with other processes for resources. Because animals evolved with resource limitation, it is important to understand how these resource-allocation decisions are made. To meet this end, I performed four investigations addressing how life-history characteristics shift in side-blotched lizards (Uta stansburiana) using laboratory studies and multi-year field sampling. First, I measured metabolic rates in response to different immune challenges and different energy states in male lizards. I found that, surprisingly, cutaneous biopsies were associated with a downregulation of metabolic rate, lipopolysaccharide injection did not affect metabolic rate, and the fastest-healing individuals had the largest decrease in metabolic rate, regardless of feeding treatment. In my second experiment, female lizards were challenged with a cutaneous biopsy and follicle-stimulating hormone to force a trade-off between the reproductive and immune systems. I learned that follicle-stimulating hormone increased metabolic rates and cutaneous biopsies decreased them, and that a combination of both treatments reduced metabolic rate the most. In my third experiment, I sampled wild lizards from northern populations in eastern Oregon and southern populations in southern Utah. In the first year, longer-lived northern lizards had higher circulating corticosterone concentration, decreased reproductive investment, and increased microbiocidal ability, but the subsequent year did not hold to these trends. A subsequent common-garden experiment revealed that southern lizards were faster at healing cutaneous wounds, but lost much more body mass than the northern individuals, which healed more slowly but maintained body mass. Finally, I have conducted a 5-year field investigation addressing the life-history trade-offs associated with urbanization, which reveals interesting effects of precipitation on survival and reproductive effort at urban and rural sites.
369

Analysis of Statnamic Load Test Data Using a Load Shed Distribution Model

Lowry, Sonia L 28 June 2005 (has links)
In the field of civil engineering, particularly structural foundations, low-cost options and time saving construction methods are important because both can be a burden on the public. Drilled shafts have proven to both lower cost and shorten construction time for large-scale projects. However, their integrity as load-carrying foundations has been questioned. The statnamic load test was conceived in the 1980s as an alternative method of testing these larger, deeper foundation elements. Performing a load test verifies that the load carrying capacity of a foundation is agreeable with the estimated capacity during the design phase and that no significant anomalies occurred during construction. The statnamic test, however, is classified as a rapid load test and requires special data regression techniques. The outcome of available regression techniques is directly related to the available instrumentation on the test shaft. Generally, the more instrumentation available, the more complete results the regression method will produce. This thesis will show that a proposed method requiring only basic instrumentation can produce more complete results using a predictive model for side shear development with displacement during the statnamic test. A driven pile or drilled shaft can be discretized into segments based on the load shed distribution model. Each segment can be analyzed as a rigid body. The total static capacity is then the summation of each segments’ contribution. Further, a weighted acceleration can be generated and used to perform an unloading point analysis.
370

Discitis after discography and chemonucleolysis / Robert D. Fraser

Fraser, Robert D. January 1986 (has links)
Bibliography: leaves 107-109 / 109 leaves, [26] leaves of plates : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (M.D.)--University of Adelaide, 1989

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