Simulação de um conversor Boost para rastreamento de máxima potência em sistemas eólicos

Trabalho de Conclusão de Curso (graduação)—Universidade de Brasília, Faculdade UnB Gama, Curso de Engenharia de Energia, 2018.Com notável potencial de crescimento na matriz energética brasileira e mundial, a energia eólica aliada a fatores socioambientais é alvo de políticas públicas voltadas à sua promoção e desenvolvimento, visando minimizar os impactos no meio ambiente causados pela geração de energia elétrica proveniente de fontes convencionais. Diante desse cenário, o presente trabalho tem como objetivo geral analisar a utilização de sistemas de controle na geração eólica, por meio do estudo e da simulação computacional de um conversor boost, afim de mostrar como essa metodologia pode otimizar a geração de energia controlando a potência mecânica da turbina eólica através do conjugado eletromagnético do gerador a ela associado. Com a finalidade de analisar diferentes algoritmos de MPPT para o rastreamento do máximo ponto de potência em sistemas eólicos, assim como implementar os algoritmos Tip Speed Ratio Control (TSRC) e Optimal Torque Control (OTC) e realizar uma comparação entre essas duas estratégias, analisando seus resultados. A implementação dos algoritmos foi realizada por meio da plataforma computacional ATP com a utilização de um modelo já existente na literatura.With remarkable growth potential in the Brazilian and world energy matrix, wind energy combined with socio-environmental factors is the target of public policies aimed at its promotion and development, aiming at minimizing the impacts on the environment caused by the generation of electricity from conventional sources. Considering this scenario, the present work has as general objective to analyze the use of control systems in wind generation, through the study and computational simulation of a boost converter, in order to show how this methodology can optimize the power generation by controlling the power wind turbine through the electromagnetic conjugate of the associated generator. In order to analyze different MPPT algorithms for maximum power point tracking in wind systems, as well as to implement the Tip Speed Ratio Control (TSRC) and Optimal Torque Control (OTC) algorithms and to compare these two strategies, results. The implementation of the algorithms was performed through the ATP computational platform using an already existing model in the literature

Chemical and bioactive properties of the oils from Brazilian nuts

This paper aims to determine the content of bioactive substances of lipid fractions extracted from Bertholletia excelsa, Lecythis pisonis and Dipteryx lacunifera, in by the interest of better identifying the quality of these raw materials. Proximate composition of nuts was determined by official methods and total carbohydrate was calculated by difference. The oils were extracted from the nuts by cold pressing and analyzed for fatty acid composition, tocopherols, phytosterols and total carotenoids and phenolics compounds. The fatty acid composition of oil extracted from L. pisonis was more unsaturated compared with others oils. L. pisonis oil showed to be richer in total tocopherol and γ-tocopherol, moreover showed considerable total phytosterol and carotenoid amounts, thus representing an important source of vitamins A and E. The oils showed significant content of phenolic compounds, with the exception of the oil extracted from D. lacunifera. The study revealed that the oils from Brazilian nuts contain bioactive compounds in relevant quantities, L. pisonis oil standing out. This fact favors their use for food and, as raw material in chemical, pharmaceutical and cosmetic industries, adding value to products derived from these oils, increasing the viable sources of raw materials

ANATOMY AND DRYING OF WOOD OF FOUR SPECIES FROM AN AGROFORESTRY SYSTEM

Drying is an important process in the generation of wood products, as it increases the quality of the final products; however, it is influenced by various anatomical characteristics. The aim of this study was to evaluate the influence of anatomy on the drying of wood of Parapiptadenia rigida (Benth.) Brenan, Peltophorum dubium (Spreng.) Taub., Eucalyptus grandis W. Hill × Eucalyptus urophylla S.T. Blake (hybrid), and Schizolobium parahyba (Vell.) Blake trees from an agroforestry system. Three trees aged 9 years were sampled for each species. The trees were removed from the study region when their diameter at breast height (DBH) was 1.30 m from the ground. Blocks were made with dimensions of 5.0 × 5.0 × 15.0 cm for the evaluation of oven drying and 1.5 × 1.5 × 2.0 cm for anatomical features. S. parahyba has the highest value of fiber diameter (35.1 µm) and lumen diameter (27.6 µm), whereas P. dubium had the highest value of cell wall thickness (6.8 µm). The average equilibrium moisture content was 10.98% after 40 days of drying. The anatomy of the wood influenced the drying of the four species intensity, which was related to humidity during all periods. The anatomical parameters that most influenced drying were fiber diameter (Pearson correlation coefficient: 0.77), lumen diameter (0.76), and fiber cell wall thickness (0.73); the higher the values, the greater was the drying intensity

CHILD LABOR: REALITY IN POTTERIES IN THE RIVER AJUAÍ COMMUNITY (PARÁ, BRAZIL)

Brazil has advanced in the legislation regarding the social protection of children and adolescents, including reference after the approval of the Statute of Children and Adolescents in 1990. However, mistreatment practices still persist, such as child labor in certain high poverty areas. This study presents an analysis of the child labor relations existing in the potteries of the Ajuaí river community, in the municipality of Abaetetuba, state of Pará, Brazil, under the analysis of the basic principles of child and adolescent protection. The research, based on a case study, involved potters and children and adolescents who worked in the potteries. The social vulnerability of families in the Ajuaí River region is one of the causes that favors the practice of a degrading action involving children and adolescents in potteries activities. Physical exertion and insecurity, besides the legal prohibition of child labor, are elements that make the activity an illegal and inhuman practice. The absence of public power with social programs that meets the basic needs of low-income families contributes to the incidence of child labor in the region

Caffeine ingestion by students at the Brazil faculty of medicine: a prospective observational cross-sectional study

Introduction: In higher education, the consumption of stimulant substances such as coffee is increasing intensely due to the high demand of concentration and disposition of individuals. This occurs mainly among medical students. Objective: It was to quantify and analyze caffeine intake and its effects on medical students at the Faculty of Medicine of Catanduva, Centro Universitário Padre Albino (UNIFIPA). Methods: This study followed a prospective observational cross-sectional model, following the rules of clinical research of the STROBE. Data collection took place from June 2019, through an objective questionnaire and self-application, which was answered by students from the first to the sixth year of FAMECA who were interested in answering and contributing to the research, which had as objective to quantify and analyze the use of caffeine, in addition to its motivations and side effects on the physiology of these students. This study was analyzed and approved by the Research Ethics Committee according to a substantiated opinion number 5,347,594, and obtaining the Informed Consent Form. For data analysis, a common descriptive analysis was performed, obtaining the values of total N, and statistical percentage (%) for all predictors. The One-Way test (ANOVA) was applied, adopting the α level lower than 0.05, with a statistically significant difference for the 95% CI. Results and Conclusion: The results of this study revealed that a very large number of university students ingest caffeine. Most of the students started consumption in the pre-college course and in college, with the aim of compensating for sleep, because they like the taste of energy drinks and improve academic performance, due to the intense routine due to the high workload requires greater attention, in order to to meet the demand for studies. Most students consume moderately caffeine, which is not harmful to health. However, a minority ingest excessive amounts of substances that contain caffeine and side effects are noted. Among these, the ones that stood out were stomach problems, anxiety and tachycardia. Thus, even representing the minority, it is of fundamental importance to carry out more studies on this topic. With this, it will be possible to provide more information to the population so that it is able to assess the impacts of the use of stimulants in clinical practice, in order to minimize possible adverse effects. Finally, the population will be able to use caffeine properly, according to the recommended dose, avoiding major health problems

Cuidando de mulheres com HIV/AIDS: uma análise interacionista na perspectiva de mulheres profissionais de saúde

Este estudo buscou conhecer os signifi cados atribuídos por mulheres, profissionais de saúde, ao processo de cuidar de mulheres com HIV, considerando a vulnerabilidade no contexto da feminização do HIV/AIDS. Estudo qualitativo baseado nos pressupostos da Grounded Theory e do Interacionismo Simbólico, realizado em duas maternidades públicas do Rio de Janeiro, de novembro de 2009 a abrilde 2010. Para coleta de dados utilizou-se a entrevista semiestruturada. Foram entrevistadas doze mulheres profi ssionais de saúde. Como categoria central emergiu “Falando como Profi ssional e Pensando no Cuidar”, cujo foco foi o signifi cado do cuidado, integrando duas categorias: a primeira traduz as inquietações do ser mulher/profi ssional cuidando de mulheres com HIV, e a segunda traz os significados dados por essas profi ssionais ao cuidado prestado às mulheres com o vírus. Conclui-se que as profi ssionais ainda trazem consigo a antiga visão do HIV/AIDS, contribuindo para o aumento da vulnerabilidade de gênero para o HIV, discriminação e preconceito.Descritores: Saúde da mulher. Síndrome de imunodefi ciência adquirida. Vulnerabilidade em saúde. Identidade de gênero

Perception of food patterns among adults using restrictive diets: a prospective observational cross-sectional study

Introduction: Obesity is a disease of increasing prevalence among adults in Brazil. It is an undesirable condition both from a health and an aesthetic point of view. The cult of the thin body sometimes motivates the adoption of restrictive diets, which significantly limit the menu. However, the use of this type of diet may be associated with unhealthy repercussions on food, well-being, and weight loss. Objective: To evaluate the perception of the dietary pattern of adult users of restrictive diets in a city in the northwest of São Paulo. Methods: Prospective observational cross-sectional study, carried out through an online questionnaire, with 108 subjects of both genders who perform/have already performed restrictive diets. Results: Predominance of female individuals (84.3%) aged between 18 and 21 years (49.1%). Regarding the Body Mass Index (BMI), 48.1% were classified within the normal range and 31.5% as preobese. In the period before the diet, 72.2% of the participants believed they were overweight. The beginning of the diet was motivated mainly by the desire to lose weight (87%) and its accomplishment happened, in most cases, without professional supervision (58.3%). Excessive eating episodes during the diet period were significant (only 14.8% never experienced it), with feelings of guilt associated in 71.3% of the cases. Conscious control during meals to avoid weight gain occurred with high frequency in 72.3% of cases. Conclusion: A portion of the population presents problematic perceptions about the experience with restrictive diets, which are associated with eating and psychological disorders

Assessment of the Accessibility of Users in Primary Health Care

Abstract Objectives: The goal of this project was to evaluate the quality of the accessibility of the adult population to services in Primary Health Care, with a view to contribute to the development of measures that will propose improvement in the offered assistance. Methods: This is a quantitative and evaluative study made in the municipality of Santa Cruz, State of Rio Grande do Norte, Brazil, with a sample of 180 people. The study was approved by the Ethics and Research Committee of the Federal University of Rio Grande do Norte under Opinion number 152/2012. Results: It was found that the adult population classified the quality of care from regular to good, showing an association with the waiting time, time spent from the unit to one's house and the reception. Conclusions: It could be concluded that this study contributes to the development of strategies able to provide a full and equitable care to the adult population in the primary health care network, since this is the gateway to other levels of care, because it aims to promote adult health and prevent diseases

SOCIODEMOGRAPHIC AND BEHAVIORAL FACTORS ASSOCIATED WITH BODY ADIPOSITY IN ADULTS

A obesidade é uma condição multicausal, caracterizada pelo excesso de peso, resultante do desequilíbrio do balanço energético. O objetivo deste estudo foi avaliar os fatores sociodemográficos e comportamentais associados ao elevado percentual de gordura corporal (GC) e à obesidade abdominal (OA), numa população adulta, servidores da Universidade Federal do Tocantins. Participaram do estudo 226 servidores, os quais foram submetidos a avaliação antropométrica, e responderam a um questionário socioeconômico e comportamental. As prevalências de sobrepeso e obesidade foram 33,09% e 16,18%, respectivamente, para mulheres e 36,67% e 16,67%, para homens, a OA esteve relacionada à idade em ambos os sexos, a GC diretamente relacionada à idade e escolaridade nos homens. 67,78% dos homens consumiam bebida alcoólica; 46,32% das mulheres eram sedentárias. Nos homens, o tabagismo esteve associado ao aumento do perímetro da cintura (PC). As prevalências de sedentarismo e consumo de bebidas alcoólicas foram consideradas elevadas em relação ao preconizado na literatura. Os percentuais de indivíduos em sobrepeso e obesidade foram maiores entre homens. O PC aumentou conforme aumento da idade nas mulheres. A GC aumentou conforme o grau de escolaridade nos homens. O tabagismo associou-se ao PC elevado nos homens, a prática de atividade física não demostrou-se fator de proteção.Obesity is a multi-causal condition, characterized by excess weight, resulting from energy balance imbalance. The objectives of this study was to evaluate the sociodemographic and behavioral factors associated with the high percentage of body fat (CG) and abdominal obesity (OA) in an adult population, servants of the Federal University of Tocantins. 226 servants participated in the study, who underwent anthropometric assessment and answered a socioeconomic and behavioral questionnaire. The prevalence of overweight and obesity was 33.09% and 16.18%, respectively, for women and 36.67% and 16.67%, for men, AO was related to age in both sexes, to BF directly related to age and schooling in men. 67.78% of men consumed alcoholic beverages; 46.32% of the women were sedentary. In men, smoking was associated with increased waist circumference (WC). The prevalence of sedentarism and consumption of alcoholic beverages were considered high in relation to that recommended in the literature. The percentages of individuals in overweight and obesity were higher among men. WC increased with increasing age in women. The BF increased according to the level of schooling in men. Smoking was associated with elevated WC in men; physical activity practice was not a protective factor