Apesar do crescente desenvolvimento das metodologias de localização de faltas fundamentadas na impedância para sistemas de distribuição de energia elétrica nas últimas décadas, alguns aspectos ainda carecem de progressos, especialmente frente à crescente necessidade de aumento da qualidade da energia elétrica entregue aos consumidores. Um destes aspectos diz respeito à consideração da capacitância das linhas de distribuição, efeito nunca dantes considerado para este fim pelas metodologias baseadas em impedância aparente. Assim sendo, o presente trabalho apresenta novos desenvolvimentos relativos à consideração do efeito capacitivo para as metodologias de localização de faltas fundamentadas na impedância para sistemas de distribuição de energia elétrica. O principal desenvolvimento apresentado é um novo equacionamento para fins de localização de faltas, que torna necessária a apresentação de outro desenvolvimento, o de um algoritmo de localização de faltas que considere a capacitância da linha. As novas equações são apresentadas para todos os tipos de faltas e constituem-se de equações polinomiais de segunda ordem em relação ao local da falta. De forma a entender a resposta destas equações frente a diferentes casos de faltas e determinar qual a solução fisicamente correta destas equações, as mesmas são analisadas sob três pontos de vista, a saber, matemático, físico, e numérico. Inicialmente estas equações são analisadas de forma analítica considerandose faltas em um mesmo local, mas com resistências diferentes. Posteriormente a mesma análise é realizada numericamente através de simulações computacionais. Os desenvolvimentos propostos são também submetidos a testes de faltas, simuladas computacionalmente em um sistema sem laterais ou cargas intermediárias. Os resultados obtidos são comparados frente a resultados obtidos também para outras metodologias que constituem atualmente o estado da arte em localização de faltas fundamentada na impedância para sistemas de distribuição de energia elétrica. Através destes resultados é possível mostrar a grande influência que o efeito capacitivo possui nestas metodologias, mesmo em sistemas aéreos de distribuição, e elucidar as grandes melhorias obtidas através dos desenvolvimentos propostos. / Despite the increasing development of impedance-based fault location techniques for electric power distribution systems in the last decades, some aspects still require to progress, especially with the increasing necessity of power quality enhancement. One of these aspects regards to the distribution line shunt admittance consideration, effect that has never been considered before by the impedance-based fault location methods for power distribution systems. In this way, this work presents further improvements regarding the capacitive effect consideration for impedance-based fault location methods for power distribution systems. The main improvement presented is the development of new fault location equations, which yield the necessity of another improvement, a modified fault location algorithm that also considers the line shunt admittance. The new equations are presented for all fault types and are constituted by second-order polynomials in relation to the fault location. In order to understand the response from these equations regarding different fault situations and determine which solution is the physically feasible one, these equations are analyzed from three different points of view, i.e., mathematical, physical, and numerical. First, the developed equations are analytically analyzed considering faults in one location with different fault resistances. After, the same analysis is numerically carried out through computational simulations. The performance of the proposed improvements are also evaluated through computational simulations of faults in a power distribution system without laterals or intermediate loads. The obtained results are compared with results from the current state-of-the-art impedance-based fault location methodologies for power distribution systems. Through these results it is possible to show the great effect that the line shunt admittance, even in aerial distribution systems, has on the existing fault location methodologies and also the great improvements brought by the proposed developments.

The forecasting of gas consumption has a fundamental importance for the natural gas distribution company, since it is common for supply companies include clauses in their contracts that force the distributor companies to perform the volume programming of the natural gas to be withdrawn, these same companies are subjected to the application of penalties if the volume exceeds programmed limits previously established. Thus, in the present work has been studied the potentialities to use of predictive models based on regression, time series and artificial neural networks in forecasting gas consumption, with the intend to improved the methodologies currently used by gas distributor in the daily schedule to send to the supplier, in a scenario characterized by the predominance of industrial consumers with dissimilar characteristics. In this context, considering the potential of forecasting techniques, has been studied the gas consumption forecasting in the medium term of both the industrial consumers and the automotive segments. From these studies it was possible to identify particular types of behaviors, and the forecasting strategy most suitable approach using artificial neural networks, time series or a combination of both. To perform these studies was developed a computational tool to analyzing, parameterize and validate methods of forecasting based on historical data consumption. The results are promising because it presents boundary conditions close to actual values. / A previsão de consumo de gás tem fundamental importância para a companhia distribuidora de gás natural, uma vez que é comum que as empresas supridoras incluam em seus contratos cláusulas que obrigam a concessionária distribuidora realizar a programação do volume de gás natural a ser retirado, sendo a mesma submetida à aplicação de penalidades caso o volume programado exceda limites previamente estabelecidos. Sendo assim, no presente trabalho tem sido estudadas as potencialidades de utilização dos modelos de previsão baseados em regressões, séries temporais e redes neurais artificiais na previsão de consumo de gás, com o objetivo de aprimorar as metodologias atualmente utilizadas pela distribuidora de gás na programação diária realizada junto ao supridor, num cenário caracterizado pela predominância de consumidores industriais com características diferentes entre si. Neste contexto, considerando o potencial das técnicas previsão, foram realizados estudos de previsão de consumo em médio prazo de consumidores dos segmentos industrial e automotivo. A partir destes estudos foi possível identificar tipos de comportamentos particulares, bem como a estratégia de previsão mais adequada, seja utilizando as redes neurais artificiais, séries temporais ou uma combinação de ambas. Para realização dos estudos uma ferramenta computacional foi desenvolvida, a qual oferece as facilidades necessárias para analisar, parametrizar e validar os métodos de previsão baseado em dados históricos de consumo. Os resultados obtidos são promissores, pois apresentam condições de contorno próximo dos valores reais.

Made available in DSpace on 2016-03-15T19:37:53Z (GMT). No. of bitstreams: 1 Lucca Zamboni.pdf: 861341 bytes, checksum: 140f5571ef3e3bfdab49cd1cb7cecfff (MD5) Previous issue date: 2007-03-19 / Ant colonies can be considered a multi-agent system, where each agent (ant) works independently by simple rules. Algorithms based on the behavior of ant colonies have been used to solve optimization problems, because in the search for food ants tend to create the shortest (optimum) path between the nest and the food source. In this work, ant inspired algorithms are used in the optimization of the topology of electric energy distribution networks. The algorithm performance is investigated in function of its parameter values. Experiments in hypothetical and actual distribution systems are performed. / Colônias de formigas podem ser consideradas um sistema multi-agente, em que cada agente (formiga) opera independentemente por regras simples. Algoritmos baseados no comportamento de colônias de formigas têm sido usados para resolver problemas de otimização, pois, na procura por alimento, as formigas tendem a estabelecer a rota mais curta (ótima) entre o formigueiro e a fonte de alimento. Neste trabalho, usam-se algoritmos inspirados em formigas na otimização da topologia de circuitos de distribuição de energia elétrica. O desempenho do algoritmo é investigado em função dos valores dos seus parâmetros. Realizam-se experimentos em sistemas de distribuição hipotéticos e realistas.

Identificar e localizar faltas em alimentadores de distribuição representa um passo importante para a melhoria da qualidade de energia, pois proporciona impactos diretos sobre o tempo de inspeção. Na verdade, a duração da inspeção implica consideravelmente no intervalo em que os consumidores estão sem energia elétrica, quando ocorre uma interrupção não programada. O objetivo deste trabalho é fornecer um sistema de detecção automática de curtos-circuitos, permitindo aos profissionais das companhias de distribuição acompanhar e monitorar de maneira on-line a ocorrência de possíveis faltas e transitórios eletromagnéticos observados na rede primária de distribuição. A abordagem de detecção utiliza um sistema híbrido que combina ferramentas inteligentes e convencionais para identificar e localizar faltas em redes primárias. Os resultados que foram compilados demonstram grande potencialidade de aplicação da proposta em sistemas de distribuição. / Efficient faults identification and location in power distribution lines constitute an important step for power quality improvement, since they provide direct impacts on the inspection time. In fact, the duration of inspection implies directly in the time interval where consumers are without power, considering here the occurrence of a non-programmed interruption. The objective of this work is to provide an automated fault detection system, allowing to the power companies engineers to online track and monitor the possible occurrence of faults and electromagnetic transients observed in the primary network for the distribution circuits. The detection approach uses a hybrid system, which combines a set of intelligent and conventional tools to identify and locate faults in the primary networks. Validation results show great application potential in distribution systems.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-04-12T20:36:16Z No. of bitstreams: 1 antoniocandiajunior.pdf: 1972311 bytes, checksum: e81012d951125a50616fee1580b50b3f (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-04-18T13:17:11Z (GMT) No. of bitstreams: 1 antoniocandiajunior.pdf: 1972311 bytes, checksum: e81012d951125a50616fee1580b50b3f (MD5) / Made available in DSpace on 2017-04-18T13:17:11Z (GMT). No. of bitstreams: 1 antoniocandiajunior.pdf: 1972311 bytes, checksum: e81012d951125a50616fee1580b50b3f (MD5) Previous issue date: 2016-12-19 / O presente trabalho apresenta uma metodologia para o planejamento da expansão de sistemas de distribuição de energia elétrica de média tensão, através da alocação ótima de equipamentos de manobra e de proteção. A proposta se enquadra na fase de planejamento associada à maximização da confiabilidade no fornecimento de energia, com mínimo custo de investimento. A técnica de otimização meta-heurística e bio inspirada denominada sistemasimunológicosartificiaisépropostaparaaplicaçãoafimdetratardemodoeficiente a característica discreta do problema de alocação de equipamentos. Um algoritmo de seleção clonal, que aplica os fundamentos da técnica citada considerando as características deredesdedistribuição, éutilizado. Índicesdeconfiabilidadedadistribuiçãosãoutilizados para avaliar a qualidade de soluções candidatas, juntamente com os respectivos custos de investimento. Portanto, as possíveis soluções são avaliadas mediante a busca de um compromisso adequado entre confiabilidade e custo, ambos critérios considerados nos procedimentos da distribuição de energia elétrica referentes à planejamento da expansão. Restrições como a presença de determinados dispositivos em pontos pré-especificados da rede são observadas e atendidas. Os equipamentos contemplados são chaves seccionadoras e de interconexão, manuais ou automáticas, disjuntores e fusíveis. Estudos de casos com quatro sistemas teste conhecidos da literatura especializada são apresentados. / The present work presents a methodology for the expansion planning of medium voltage electric power distribution systems through the optimal allocation of maneuvering and protectionequipment. Theproposalfitsintotheplanningphaseassociatedwithmaximizing reliability in energy supply, with minimum investment cost. The meta-heuristic and bioinspiredoptimizationtechniquecalledartificialimmunologicalsystemsisproposedinorder to efficiently treatthe discrete characteristicof the equipment allocation problem. A clonal selection algorithm, which make use of the fundamentals of the cited technique considering thecharacteristicsofdistributionnetworks,isused. Distributionreliabilityindicesareused toevaluatethequalityofcandidatesolutions,togetherwiththerespectiveinvestmentcosts. Therefore, the possible solutions are evaluated by searching for an adequate compromise between reliability and cost, both criteria considered in the procedures of the distribution of electric power related to the expansion planning. Restrictions such as the presence of certaindevicesatpre-specifiedpointsinthenetworkareobservedandmet. Theequipments contemplated are disconnecting and interconnecting switches, manual or automatic, circuit breakers, reclosers and fuses. Case studies with four test systems from the specialized literature are presented.

This work deals with crytpoanalysis, calculation performance and its distribution. It describes the methods of distributing the calculation performance for the needs of crypto analysis. Further it focuses on other methods allowing the speed increasing in breaking the cryptographic algorithms especially by means of the hash functions. The work explains the relatively new term of cloud computing and its consecutive use in cryptography. The examples of its practical utilisation follow. Also this work deals with possibility how to use grid computing for needs of cryptoanalysis. At last part of this work is system design using „cloud computing“ for breaking access password.

Antibiotic resistance in clinical bacterial isolates remains an ongoing problem requiring continuous monitoring to effect some form of control. Comparative studies have not been previously reported for the Eastern Cape Region, South Africa and this study was undertaken to monitor resistance patterns in clinical isolates from Provincial Hospital, Port Elizabeth. Over the three year period 1989 to 1991, 9888 susceptibility results from isolates examined in the SAIMR pathology laboratory were analysed and collated using a stand-alone computer program. Resistance patterns for a range of nineteen antibiotics were collated for isolates from various sampling points within the hospital. Results were reported as resistance patterns in individually isolated species. Levels of resistance in each species were compared to those reported from South Africa and abroad, and changing patterns of resistance were noted within the three year period at the Provincial Hospital, Port Elizabeth.

No description available.

The energy demand is increasing very rapidly all over the world. Solar energy is one renewable solution to cover the energy demand. Solar power is a universal green energy source, and we receive from the sun more than ten thousand times energy than it has needed on the earth. This report investigates the electricity generation by using solar PV panels for the given village as well as the transmission systems. The main priority of this report is to calculate the demand electricity of the village, plant design also considering the power losses. Three different scenarios to transmit the generated power to the consumers end were considered and studied. The three different cases and cases are, • Grid connection. • Micro-grid power supply system with full battery storage. • Micro-grid power supply system with partial battery storage. All three system were analyzed based on the technical specifications, power losses during transmission. The all calculation was completed by the help of different software, such as PVGIS, MS excel, different empirical formulas and previous research papers. To complete the calculation this, report also consider a few assumptions. After completing all analysis and calculations, the research outcome was showing that the microgrid power supply system with whole battery backup storage will be the better solution both technically and economically. Photovoltaic (PV) solar cell-based microgrid systems can be one of the most feasible solutions to provide electricity in rural areas. Therefore, this system can play a vital role in Bangladesh to provide electricity in rural areas. In Bangladesh, there are several positive aspects to promote the use of photovoltaics (PV), such as many solar irradiations, low technology and labour cost, and a few subsidies from the government.

Elderly people, or those over 65 years of age, are known to comprise 10% of the United States population today and are projected to reach nearly 12% by the year 2000. Further, 5% of this population is reported to be institutionalized resulting in approximately 1.1 million chronic care patients or 0.5% of the population. The use of drugs in this population comprises approximately 25% of the prescription drug market in the United States which is directly related to the greater occurrence of pathological problems associated with the aging process. While it is evident that the beneficial outcome of drug therapies is partially related to the increased longevity observed in these elderly people, this population is also well-known to be the most prone to adverse drug reactions. Factors complicating drug use in the elderly include high usage, chronic therapy, long-term hospitalization, inappropriate and multiple prescribing of drugs, inadequate monitoring of adverse drug effects, susceptibility to physical deterioration and senility. Therefore, the objective of this project is to test the hypothesis that the quality and cost of drug therapy in SNF patients can be significantly improved by implementing measures to improve the utilization of drugs.