Sistema de medição de energia baseado no medidor de energia Teridian 71M6515H

Esta tese de mestrado descreve o desenvolvimento, implementação e teste de um sistema de medição de energia concebido para um ambiente doméstico, baseado no circuito integrado medidor de energia Teridian 71M6515H. O sistema desenvolvido envia periodicamente os valores monitorizados para uma base de dados, através de uma rede sem fios com base no protocolo IEEE 802.11 (Wi-Fi). Os dados podem ser acedidos remotamente em tempo real, através de uma página na internet, onde é possível consultar a quantidade de energia consumida acumulada. Na primeira fase deste trabalho realizou-se o enquadramento do tema no contexto atual, realizando-se o estudo de alguns sistemas domésticos de monitorização do consumo de energia elétrica existentes no mercado. Numa segunda fase foi realizado o estudo dos componentes a serem utilizados, o desenho da placa de circuito impresso e o desenvolvimento do firmware, para que todo o processamento e manipulação dos dados fossem realizados pela unidade de aquisição de dados. Em seguida procedeu-se à construção da unidade de aquisição e à programação para o registo dos valores numa base de dados. A última fase consistiu nos testes de funcionamento da unidade de aquisição em conjunto com a aplicação de registo de dados. Com a implementação do sistema desenvolvido o consumidor doméstico poderá ter conhecimento, em tempo real, do custo de funcionamento dos equipamentos que possui e assim tomar decisões para os utilizar de forma mais racional, o que se pode traduzir numa economia dos recursos energéticos.

Estado nutricional antropométrico, perfil lipídico e consumo alimentar como fatores de risco para doença cardiovascular em adolescentes

The dyslipidemia and excess weight in adolescents, when combined, suggest a progression of risk factors for cardiovascular disease (CVD). Besides these, the dietary habits and lifestyle have also been considered unsuitable impacting the development of chronic diseases. The study objectives were: (1) estimate the prevalence of lipid profile and correlate with body mass index (BMI), waist circumference (WC) and waist / height ratio (WHR) in adolescents, considering the maturation sexual, (2) know the sources of variance in the diet and the number of days needed to estimate the usual diet of adolescents and (3) describe the dietary patterns and lifestyle of adolescents, family history of CVD and age correlates them with the patterns of risk for CVD, adjusted for sexual maturation. A cross-sectional study was performed with 432 adolescents, aged 10-19 years from public schools of the Natal city, Brazil. The dyslipidemias were evaluated considering the lipid profile, the index of I Castelli (TC / HDL) and II (LDL / HDL) and non-HDL cholesterol. Anthropometric indicators were BMI, WC and WHR. The intake of energy, nutrients including fiber, fatty acids and cholesterol was estimated from two 24-hour recalls (24HR). The variables of lipid profile, anthropometric and clinical data were used in the models of Pearson correlation and linear regression, considering the sexual maturation. The variance ratio of the diet was calculated from the component-person variance, determined by analysis of variance (ANOVA). The definition of the number of days to estimate the usual intake of each nutrient was obtained by taking the hypothetical correlation (r) ≥ 0.9, between nutrient intake and the true observed. We used the principal component analysis as a method of extracting factors that 129 accounted for the dependent variables and known cardiovascular risk obtained from the lipid profile, the index for Castelli I and II, non-HDL cholesterol, BMI, and WC the WHR. Dietary patterns and lifestyle were obtained from the independent variables, based on nutrients consumed and physical activity weekly. In the study of principal component analysis (PCA) was investigated associations between the patterns of cardiovascular risk factors in dietary patterns and lifestyle, age and positive family history of CVD, through bivariate and multiple logistic regression adjusted for sexual maturation. The low HDL-C dyslipidemia was most prevalent (50.5%) for adolescents. Significant correlations were observed between hypercholesterolemia and positive family history of CVD (r = 0.19, p <0.01) and hypertriglyceridemia with BMI (r = 0.30, p <0.01), with the CC (r = 0.32, p <0.01) and WHR (r = 0.33, p <0.01). The linear model constructed with sexual maturation, age and BMI explained about 1 to 10.4% of the variation in the lipid profile. The sources of variance between individuals were greater for all nutrients in both sexes. The reasons for variances were  1 for all nutrients were higher in females. The results suggest that to assess the diet of adolescents with greater precision, 2 days would be enough to R24h consumption of energy, carbohydrates, fiber, saturated and monounsaturated fatty acids. In contrast, 3 days would be recommended for protein, lipid, polyunsaturated fatty acids and cholesterol. Two cardiovascular risk factors as have been extracted in the ACP, referring to the dependent variables: the standard lipid profile (HDL-C and non-HDL cholesterol) and "standard anthropometric index (BMI, WC, WHR) with a power explaining 75% of the variance of the original data. The factors are representative of two independent variables led to dietary patterns, "pattern 130 western diet" and "pattern protein diet", and one on the lifestyle, "pattern energy balance". Together, these patterns provide an explanation power of 67%. Made adjustment for sexual maturation in males remained significant variables: the associations between puberty and be pattern anthropometric indicator (OR = 3.32, CI 1.34 to 8.17%), and between family history of CVD and the pattern lipid profile (OR = 2.62, CI 1.20 to 5.72%). In females adolescents, associations were identified between age after the first stage of puberty with anthropometric pattern (OR = 3.59, CI 1.58 to 8.17%) and lipid profile (OR = 0.33, CI 0.15 to 0.75%). Conclusions: The low HDL-C was the most prevalent dyslipidemia independent of sex and nutritional status of adolescents. Hypercholesterolemia was influenced by family history of CVD and sexual maturation, in turn, hypertriglyceridemia was closely associated with anthropometric indicators. The variance between the diets was greater for all nutrients. This fact reflected in a variance ratio less than 1 and consequently in a lower number of days requerid to estimate the usual diet of adolescents considering gender. The two dietary patterns were extracted and the pattern considered unhealthy lifestyle as healthy. The associations were found between the patterns of CVD risk with age and family history of CVD in the studied adolescents

Custo de energia elétrica em cultura do feijoeiro irrigado por pivô central, afetado pelo manejo da irrigação e sistemas de cultivo

O objetivo deste trabalho foi analisar o consumo e o custo de energia elétrica em cultura do feijoeiro irrigado por pivô central, cultivar IAC-Carioca, submetida a dois manejos de irrigação: TENS - tensiometria; TCA - balanço hídrico-climatológico, baseado no tanque Classe A; e dois sistemas de cultivo em Latossolo Vermelho: PD - plantio direto; PC - plantio convencional, no ano de 2002. A pesquisa foi desenvolvida na Área Demonstrativa e Experimental de Irrigação - ADEI da FCAV/UNESP, Câmpus de Jaboticabal - SP. O consumo de energia elétrica do sistema de irrigação foi monitorado, e seu custo, analisado para dois grupos tarifários: A e B, sendo os preços do kWh dos sistemas tarifários de energia elétrica obtidos na CPFL (Companhia Paulista de Força e Luz). Os tratamentos em que o manejo da irrigação foi realizado pelo método do tanque Classe A, ocasionaram os maiores consumos e custos de energia elétrica, em relação aos tratamentos em que o manejo foi realizado por tensiometria; entre os sistemas de plantio, não foram observadas diferenças. A tarifa Horo-Sazonal (verde e/ou azul), com desconto, foi a melhor opção para os quatro tratamentos.

Viabilidade econômica da utilização do biogás produzido em granja suínícola para geração de energia elétrica

A produção de biogás por meio de biodigestão anaeróbia representa um avanço para equacionar o problema dos dejetos produzidos pela suinocultura e disponibilidade de energia no meio rural. Este trabalho teve como objetivo estimar a viabilidade econômica de um sistema biointegrado para geração de eletricidade a partir do aproveitamento de dejetos de suínos. Os dados para este estudo foram coletados em uma agroindústria, onde são realizadas diversas atividades agrícolas; entretanto, a suinocultura foi selecionada para o processo de análise de biodigestão anaeróbia, pelo fato de gerar uma grande quantidade de dejetos, com dificuldade de disposição no meio ambiente, configurando um estudo de caso. O biodigestor analisado é um modelo tubular contínuo, com calha de água em alvenaria e com uma manta plástica como gasômetro, onde são depositados diariamente os dejetos de 2.300 suínos em fase de terminação. O investimento inicial para implantação foi estimado em R$ 51.537,17, e os custos anuais do sistema foram de R$ 5.708,20 com manutenção, R$ 4.390,40 com depreciação e R$ 1.366,77 com juros. Concluiu-se que o sistema de produção de biogás é viável do ponto de vista econômico, se o consumo de energia elétrica for de 35 kWh por dia, em média, onde o valor presente líquido (VLP) é de R$ 9.494,90, e a taxa interna de retorno (TIR) é de 9,34% ao ano.

Extração e Representação de Conhecimento de Séries Temporais de Demanda de Energia Elétrica Usando TSKR

The opening of the Brazilian market of electricity and competitiveness between companies in the energy sector make the search for useful information and tools that will assist in decision making activities, increase by the concessionaires. An important source of knowledge for these utilities is the time series of energy demand. The identification of behavior patterns and description of events become important for the planning execution, seeking improvements in service quality and financial benefits. This dissertation presents a methodology based on mining and representation tools of time series, in order to extract knowledge that relate series of electricity demand in various substations connected of a electric utility. The method exploits the relationship of duration, coincidence and partial order of events in multi-dimensionals time series. To represent the knowledge is used the language proposed by Mörchen (2005) called Time Series Knowledge Representation (TSKR). We conducted a case study using time series of energy demand of 8 substations interconnected by a ring system, which feeds the metropolitan area of Goiânia-GO, provided by CELG (Companhia Energética de Goiás), responsible for the service of power distribution in the state of Goiás (Brazil). Using the proposed methodology were extracted three levels of knowledge that describe the behavior of the system studied, representing clearly the system dynamics, becoming a tool to assist planning activities

Impacto do racionamento nos resultados das empresas concessionárias do serviço público de distribuição de energia elétrica: um estudo nas empresas privadas da Região Nordeste

This work verifies the impact caused by the Emergencial Program of Reduction of Consumption of Electric Energy (energy-rationing program) in the results of the concessionary private companies of the public service of electric energy distribution localized in the Northeast Area. As the rationing invigorated from June 2001 to February 2002, its effects are diluted in the results presented by these companies in the second semester of 2001 and first quarter of 2002, with prominence for the last quarter of 2001, when the revenue of extraordinary tariff restore was instituted by the National Agency of Electric Energy (ANEEL), consequence of the so-called General Agreement of the Electric Sector made between the federal government and the companies of the electric sector. The structure of a generic electric sector and a historical review of the Brazilian electric sector from the time it was controlled by the private enterprises, including the State control period, about 1960, and returning to the control of the private enterprises in 1990, under a new regulation structure are presented. An explanation of the models of economic regulation that Brazil used for the electric sector is made, with prominence for the price cap that is the actual effective model. The process of tariff revision foreseen in the concession contracts signed by the federal government and the concessionary companies is presented, highlighting its two stages: the tariff rebalancing that defines the new price cap and the calculation of the factor X that establishes the efficiency goals for the companies. There is made a presentation of the Emergencial Program of Reduction of Consumption of Electric Energy and of the consequent General Agreement of the Electric Sector, which created the revenue of extraordinary tariff restore. A conceptual revision on reviews is presented, regarding to concepts, accomplishment and recognition. A brief review of the six companies that made part of the worked sample is also presented. Analyzing the quarters historical review and of amount of sold energy, it was possible to conclude that the energy-rationing altered the results of the studied companies significantly and that alteration was masked by the accounting process of the revenue of extraordinary tariff restore

La dinámica del consumo energético industrial en América Latina y sus implicancias para un desarrollo sostenible

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Mini-inversores para aproveitamento de energia fotovoltaica, com técnicas de MPPT, sincronismo e conexão com a rede de CA em BT, proteção de ilhamento, gerenciamento da energia e da operação

Pós-graduação em Engenharia Elétrica - FEIS

Consumo alimentar familiar e indicadores antropométricos do estado nutricional de escolares de Piracicaba-SP

Pós-graduação em Alimentos e Nutrição - FCFAR

Racionalização da energia elétrica com aplicação da legislação tarifária em indústria de embalagem plástica

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Viabilidade econômica e financeira da utilização do excedente de energia elétrica co-gerada em uma usina de açúcar e álcool da Alta paulista

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Alternativas para a cogeração de energia em uma indústria de chapas de fibra de madeira

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Istmo Centroamericano: estadísticas de energía eléctrica, 1980

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Istmo Centroamericano: estadísticas de energía eléctrica, 1981

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