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ASSOCIATIONS BETWEEN MORPHOMETRIC CHARACTERISTICS OF THE REPRODUCTIVE TRACT AND FERTILITY IN BEEF CATTLEBattista, Sarah E. January 2019 (has links)
No description available.
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DIAGNÓSTICO DE FALHAS INCIPIENTES EM TRANSFORMADORES DE POTÊNCIA UTILIZANDO A TEORIA DA EXTENSÃO / FAULT INCIPIENT DIAGNOSIS IN POWER TRANSFORMERS USING EXTENSION THEORYLima, Shigeaki Leite de 01 August 2008 (has links)
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Previous issue date: 2008-08-01 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Power transformers play an important role in the power energy supply, demanding the continuous
monitoring of process that could lead to operation faults, specifically in the equipment
electric insulation. Methods considered in the standards IEC, IEEE and NBR7274
for dissolved gas analysis (DGA) do not provide good levels of accuracy, because there are
scenarios with oil samples that lead to contradictory evaluations. The extension theory
is a method based on the idea that contradiction can be transformed into compatible
problems. In this work, this theory is applied for solving incompatibilities found in the
application of the standard NBR7274 for incipient detection faults (the modified Roger s
Method). In order to validate the approach, several test cases from recent literature have
been implemented and included. The approach has shown good comparative performance
in the fault identification process. / Os transformadores de potência cumprem um papel decisivo na continuidade do fornecimento
de energia elétrica, obrigando um monitoramento contínuo dos processos que possam
provocar falhas de operação, que particularmente ocorrem no isolamento do equipamento.
Os métodos previstos na IEC, IEEE e NBR7274 para análise do gás dissolvido
(AGD), não alcançam nível pleno de acerto, pois existem situações nas amostras de óleo
que geram resultados contraditórios e incompatíveis. A Teoria da Extensão é um método
baseado na idéia de que contradições podem ser transformadas em problemas compatíveis.
Neste trabalho tal metodologia é aplicada para resolver incompatibilidades encontradas
no diagnóstico feito com a NBR7274 (método de Rogers modificado) para detecção de
falhas incipientes. O método consiste em modelar a NBR e analisar os resultados quanto
ao grau de acerto obtido. Foram feitos testes com vários estudos de caso disponíveis na
literatura técnica, mostrando-se bem promissor na identificação das falhas.
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Estudo da recupera??o de ?leo por drenagem gravitacional assistida por inje??o de vaporBarillas, Jennys Lourdes Meneses 22 February 2008 (has links)
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Previous issue date: 2008-02-22 / Steam assisted gravity drainage process (SAGD) involves two parallel horizontal wells located in a same vertical plane, where the top well is used as steam injector and the bottom
well as producer. The dominant force in this process is gravitational. This improved oil recovery method has been demonstrated to be economically viable in commercial projects of oil recovery for heavy and extra heavy oil, but it is not yet implemented in Brazil. The study of this technology in reservoirs with characteristics of regional basins is necessary in order to
analyze if this process can be used, minimizing the steam rate demand and improving the process profitability. In this study, a homogeneous reservoir was modeled with characteristics
of Brazilian Northeast reservoirs. Simulations were accomplished with STARS , a commercial software from Computer Modelling Group, which is used to simulate improved oil recovery process in oil reservoirs. In this work, a steam optimization was accomplished in reservoirs with different physical characteristics and in different cases, through a technical-economic analysis. It was also studied a semi-continuous steam injection or with injection stops. Results showed that it is possible to use a simplified equation of the net present value, which incorporates earnings and expenses on oil production and expenses in steam
requirement, in order to optimize steam rate and obtaining a higher net present value in the process. It was observed that SAGD process can be or not profitable depending on reservoirs
characteristics. It was also obtained that steam demand can still be reduced injecting in a non continuous form, alternating steam injection with stops at several time intervals. The
optimization of these intervals allowed to minimize heat losses and to improve oil recovery / O processo de drenagem gravitacional com inje??o cont?nua de vapor (SAGD) envolve dois po?os horizontais paralelos localizados em uma mesma vertical, onde o po?o superior ? usado como injetor de vapor e o inferior como produtor. A for?a dominante neste processo ? a gravitacional. Este m?todo de recupera??o avan?ada tem sido demonstrado ser economicamente vi?vel em projetos comerciais de recupera??o de petr?leo pesado e extra pesado, mas ainda n?o foi implementado no Brasil. O estudo desta tecnologia em
reservat?rios com caracter?sticas das bacias regionais ? necess?rio para analisar como se ad?qua o processo para minimizar a demanda de vapor obtendo a maior rentabilidade do
processo. Neste estudo foi usado um modelo homog?neo com caracter?sticas de reservat?rios do Nordeste Brasileiro. As simula??es foram realizadas em um programa comercial da
Computer Modelling Group , o STARS , m?dulo usado para realizar estudos de m?todos de recupera??o avan?ada de reservat?rios de ?leo. Neste trabalho, foi realizada uma
otimiza??o do vapor em reservat?rios com diferentes caracter?sticas f?sicas e em diferentes cen?rios, atrav?s de uma an?lise t?cnico-econ?mica. Tamb?m foi estudada a inje??o de vapor semi-cont?nua ou com paradas. Os resultados obtidos mostraram que ? poss?vel utilizar uma equa??o simplificada do valor presente l?quido, que incorpora os ganhos e gastos na produ??o de ?leo e os gastos na inje??o de vapor, para otimizar a demanda do vapor obtendo um maior valor presente l?quido no processo. Observou-se que o m?todo (SAGD) pode ser ou n?o
rent?vel dependendo das caracter?sticas do reservat?rio. Encontrou-se tamb?m que a necessidade de vapor pode ainda ser diminu?da utilizando esquemas de inje??o de vapor com
paradas em intervalos de tempo otimizados, e isto permitiu minimizar as perdas de calor e melhorar a recupera??o.
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Zatížení pacientek při mamografických vyšetřeních / Evaluation of patient dose in mammographyPolášková, Markéta January 2008 (has links)
Breast cancer presents serious epidemiological problem, in result of which die more than 2 000 czech women every year. Screening mammography is one of the most expanded and most effective examinations for early detection of this desease but one has to take into account an inconsiderable risk connected with the procedure based on X-ray ionizing radiation. This diploma thesis deals with evaluation of the dose absorbed by the tissue. It contains the description of evaluation of the average dose in glandular tissue on PMMA phantom, as well as results of the measurements on conventional and digital mammograph. A data file with exposure parameters from mammography screening is included and interpreted. Also the Monte Carlo method was used for the dose evaluation, the thesis contains the brief description of the method, concept of analysis model in mammography and results of simulations.
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