999 resultados para Energia eletrica - Custo social


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Esse trabalho investiga empiricamente a relação entre custo de agência e as medidas de monitoramento interno disponíveis aos investidores brasileiros nas empresas nacionais, utilizando amostras de companhias abertas entre os anos de 2010 e 2014, totalizando 134 empresas analisadas e 536 observações. Para medir tal relação, foram utilizadas, como variáveis de monitoramento interno, informações sobre a remuneração variável dos executivos, entre elas o uso de outorgas de opções de compra de ações, a composição do conselho de administração, dando ênfase à representatividade dos conselheiros independentes e à dualidade entre Chairman e CEO, e o percentual do capital social das companhias que está sob propriedade dos executivos. Como proxy para custo de agência, foram utilizados os indicadores Asset Turnover Ratio e General & Administrative Expenses (G&A) como percentual da Receita Líquida. Neste contexto, foram estabelecidas duas hipóteses de pesquisa e estimados modelos de regressão em painel controlados por efeitos fixos de tempo e empresa, empregando como variável dependente as variáveis proxy do custo de agência e utilizando as variáveis endividamento e tamanho das empresas como variáveis de controle. Os resultados dos modelos demonstram que, na amostra selecionada, há uma relação positiva e significativa entre o percentual da remuneração variável e as proxies de custo de agência, comportamento este contrário ao esperado originalmente. Conclui-se assim que as empresas que apresentam uma maior composição variável no total remunerado ao executivo, incorrem em um maior custo de agência, o que leva à conclusão de que tais ferramentas não são boas estratégias de alinhamento de interesses entre executivos e acionistas. As demais variáveis de monitoramento interno não apresentaram significância.

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O Relatório de Sustentabilidade é um instrumento que visa dar maior transparência às atividades empresariais e ampliar o diálogo da organização com a sociedade, tendo em vista a necessidade de comunicar aos stakeholders suas práticas socioambientais, além das econômicas. A presente pesquisa buscou compreender de que forma as empresas do segmento de energia elétrica, listadas na BM&F BOVESPA como Nível 1 e Novo Mercado de Governança Corporativa divulgam aos interessados seus Relatórios de Sustentabilidade. Realizou-se análise documental, através dos Relatórios de Sustentabilidade das empresas do setor elétrico: CEEE, Cemig, Cesp, Copel, CPFL, CTEEP, EDP, Eletrobrás, Equatorial, Light, Tractebel e MPX. Foram analisados os relatórios referentes aos anos de 2010, 2011 e 2012. Houve uma sutil evolução na divulgação dos indicadores da GRI-Global Reporting Initiative, possivelmente por serem reconhecidos internacionalmente, o que proporciona às empresas maior confiabilidade e transparência em suas informações.

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The humanity reached a time of unprecedented technological development. Science has achieved and continues to achieve technologies that allowed increasingly to understand the universe and the laws which govern it, and also try to coexist without destroying the planet we live on. One of the main challenges of the XXI century is to seek and increase new sources of clean energy, renewable and able to sustain our growth and lifestyle. It is the duty of every researcher engage and contribute in this race of energy. In this context, wind power presents itself as one of the great promises for the future of electricity generation . Despite being a bit older than other sources of renewable energy, wind power still presents a wide field for improvement. The development of new techniques for control of the generator along with the development of research laboratories specializing in wind generation are one of the key points to improve the performance, efficiency and reliability of the system. Appropriate control of back-to-back converter scheme allows wind turbines based on the doubly-fed induction generator to operate in the variable-speed mode, whose benefits include maximum power extraction, reactive power injection and mechanical stress reduction. The generator-side converter provides control of active and reactive power injected into the grid, whereas the grid-side converter provides control of the DC link voltage and bi-directional power flow. The conventional control structure uses PI controllers with feed-forward compensation of cross-coupling dq terms. This control technique is sensitive to model uncertainties and the compensation of dynamic dq terms results on a competing control strategy. Therefore, to overcome these problems, it is proposed in this thesis a robust internal model based state-feedback control structure in order to eliminate the cross-coupling terms and thereby improve the generator drive as well as its dynamic behavior during sudden changes in wind speed. It is compared the conventional control approach with the proposed control technique for DFIG wind turbine control under both steady and gust wind conditions. Moreover, it is also proposed in this thesis an wind turbine emulator, which was developed to recreate in laboratory a realistic condition and to submit the generator to several wind speed conditions.

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While essential to human nature, health and life have been protected since ancient times by various areas of knowledge, particularly by the Law, given its dynamics within the regulation of social interactions. In Brazil, health has been granted major importance by the Federal Constitution of 1988, which, disrupting the dictatorial authoritarianism, inaugurating a Social State and focusing on the values of freedom and human dignity, raises health to the condition of a social right, marked predominantly by an obligational bias directed, primarily, to the State, through the enforcement of public policies. Although, given the limitation of the State action to the reserve for contingencies, it turns clear that an universalizing access to public health is impossible, seen that the high cost of medical provisions hinders the State to meet all the health needs of the rightholders. As a result of the inefficiency of the State, the effort of the Constituent Assembly of 1988 in creating a hybrid health system becomes nuclear, which, marked by the possibility of exploration of healthcare by the private initiative, assigns to the private enterprise a key role in supplementing the public health system, especially through the offer of health insurance plans. At this point, however, it becomes clear that health provisions rendered by the private agents are not unlimited, which involves discussions about services and procedures that should be excluded from the contractual coverage, for purposes of sectoral balance, situation which draws the indispensability of deliberations between Fundamental Rights on one hand, related to the protection of health and life, and contractual principles on the other hand, connected to the primacy of private autonomy. At this point, the importance of the regulation undertaken by the ANS, Brazilian National Health Agency, appears primordial, which, by means of its seized broad functions, considerable autonomy and technical discretion, has conditions to implement an effective control towards the harmonization of the regulatory triangle, the stability and development of the supplementary health system and, consequently, towards the universalization of the right to health, within constitutional contours. According to this, the present essay, resorting to a broad legislative, doctrinal and jurisprudential study, concludes that economic regulation over the private healthcare sector, when legitimately undertaken, provides progress and stability to the intervening segment and, besides, turns healthcare universalization feasible, in a way that it can not be replaced efficiently by any other State function.

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The acceleration of technological change and the process of globalization has intensified competition and the need for new products (goods and services), resulting in growing concern for organizations in the development of technological, economic and social advances. This work presents an overview of the development of wind energy-related technologies and design trends. To conduct this research, it is (i) a literature review on technological innovation, technological forecasting methods and fundamentals of wind power; (ii) the analysis of patents, with the current technology landscape studied by means of finding information in patent databases; and (iii) the preparation of the map of technological development and construction of wind turbines of the future trend information from the literature and news from the sector studied. Step (ii) allowed the study of 25 644 patents between the years 2003-2012, in which the US and China lead the ranking of depositors and the American company General Electric and the Japanese Mitsubishi stand as the largest holder of wind technology. Step (iii) analyzed and identified that most of the innovations presented in the technological evolution of wind power are incremental product innovations to market. The proposed future trends shows that the future wind turbines tend to have a horizontal synchronous shaft, which with the highest diameter of 194m and 164m rotor nacelle top, the top having 7,5MW generation. The materials used for the blades are new materials with characteristics of low density and high strength. The towers are trend with hybrid materials, uniting the steel to the concrete. This work tries to cover the existing gap in the gym on the use of technological forecasting techniques for the wind energy industry, through the recognition that utilize the patent analysis, analysis of scientific articles and stories of the area, provide knowledge about the industry and influencing the quality of investment decisions in R & D and hence improves the efficiency and effectiveness of wind power generation

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En Brasil, la violencia interpersonal (homicidios) se ha incrementado de forma significativa, convirtiéndose en una preocupación cada vez mayor en todos los ámbitos políticos de la sociedad. Hoy es uno de los más graves problemas sociales y de salud pública. Se refiere a los problemas sociales, ya que interfiere en la distribución de la oferta de bienes y servicios a los ciudadanos; sino también un problema de salud, porque la violencia es uno de los fenómenos que causan gran impacto en la morbilidad y mortalidad del país, y genera un alto costo para el Sistema Único de Saúde (SUS). Esta es una crisis social, que es el resultado de un mundo capitalista globalizado, que exige a todos sus instrumentos de dominación (dinero, poder y competitividad en estado puro), en virtud del cual la violencia y los conflictos interpersonales se materializan en el territorio. El Río Grande do Norte (RN) ha estado siguiendo esta realidad que es nacional, con el aumento de las tasas de mortalidad por homicidios. En este sentido, este estudio tuvo como objetivo analizar la violencia interpersonal (agresión / homicidio), en Brasil y en el estado del RN, para entender cómo esto afecta a su población, en la morbilidad y mortalidad durante los años 2001 a 2011. Para ambos hicimos uso de método descriptivo / cuantitativo para determinar la magnitud, el tamaño, el perfil de las víctimas y los costos del SUS generados por el problema. Como resultado, podemos diagnosticar que en Brasil, la violencia se ha presentado una nueva dinámica regional, promovida por un proceso de interiorización del fenómeno en todo el país, este proceso de internalización se ha reflejado en la última década, el crecimiento de la violencia en el estado del RN, que ha causado un gran impacto en las tasas de la mortalidad del estado. Acerca la victimización, se puede ver que hay un perfil vulnerable formado por, varón, baja instrucción joven, sola y negro. Con respecto a los datos de morbilidad hospitalaria, la demanda creciente del fenómeno genera costes para el sistema de salud, y las graves consecuencias humanas, como la escalada del miedo y la destrucción de una generación de jóvenes brasileños. Por lo tanto, la falta de una política pública para afrontamiento, prevención y mitigación del problema revela el fracaso de la gestión pública, con consecuencias sociales y de salud, tanto individual como colectivamente.

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Energy is a vital resource for social and economic development. In the present scenario, the search for alternative energy sources has become fundamental, especially after the oil crises between 1973 and 1979, the Chernobyl nuclear accident in 1986 and the Kyoto Protocol in 1997. The demand for the development of new alternative energy sources aims to complement existing forms allows to meet the demand for energy consumption with greater security. Brazil, with the guideline of not dirtying the energy matrix by the fossil fuels exploitation and the recent energy crisis caused by the lack of rains, directs energy policies for the development of other renewable energy sources, complementing the hydric. This country is one of the countries that stand out for power generation capacity from the winds in several areas, especially Rio Grande do Norte (RN), which is one of the states with highest installed power and great potential to be explored. In this context arises the purpose of this work to identify the incentive to develop policies of wind energy in Rio Grande do Norte. The study was conducted by a qualitative methodology of data analysis called content analysis, oriented for towards message characteristics, its informational value, the words, arguments and ideas expressed in it, constituting a thematic analysis. To collect the data interviews were conducted with managers of major organizations related to wind energy in Brazil and in the state of Rio Grande do Norte. The identification of incentive policies was achieved in three stages: the first seeking incentives policies in national terms, which are applied to all states, the second with the questionnaire application and the third to research and data collection for the development of the installed power of the RN as compared to other states. At the end, the results demonstrated hat in Rio Grande do Norte state there is no incentive policy for the development of wind power set and consolidated, specific actions in order to optimize the bureaucratic issues related to wind farms, especially on environmental issues. The absence of this policy hinders the development of wind energy RN, considering result in reduced competitiveness and performance in recent energy auctions. Among the perceived obstacles include the lack of hand labor sufficient to achieve the reporting and analysis of environmental licenses, the lack of updating the wind Atlas of the state, a shortfall of tax incentives. Added to these difficulties excel barriers in infrastructure and logistics, with the lack of a suitable port for large loads and the need for reform, maintenance and duplication of roads and highways that are still loss-making. It is suggested as future work the relationship of the technology park of energy and the development of wind power in the state, the influence of the technology park to attract businesses and industries in the wind sector to settle in RN and a comparison of incentive policies to development of wind energy in the Brazilian states observing wind development in the same states under study.

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This research is presented as a comparative study about the baking capacity of two box type ovens, produced from a packing case used to equipment transportation. The two ovens have different internal settings, with the greenhouse effect and the concentration of incident solar radiation as the main parameters of differentiation. The main features of the ovens are the low cost, the reuse of materials, the manufacturing and assembly processes simplified, the easy management and the ability of baking a variety of foods simultaneously. The manufacturing and operation of the ovens can be handled by any social and intellectual level of people. The feasibility of the ovens to bake the tested foods was proved with success, ensuring the supremacy of the mirrored oven. The results obtained for both ovens were competitive even with the conventional gas oven, producing the baking of three cakes with 750g in just 80 minutes.

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This work aims at modeling power consumption at the nodes of a Wireless Sensor Network (WSN). For doing so, a finite state machine was implemented by means of SystemC-AMS and Stateflow modeling and simulation tools. In order to achieve this goal, communication data in a WSN were collected. Based on the collected data, a simulation environment for power consumption characterization, which aimed at describing the network operation, was developed. Other than performing power consumption simulation, this environment also takes into account a discharging model as to analyze the battery charge level at any given moment. Such analysis result in a graph illustrating the battery voltage variations as well as its state of charge (SOC). Finally, a case study of the WSN power consumption aims to analyze the acquisition mode and network data communication. With this analysis, it is possible make adjustments in node-sensors to reduce the total power consumption of the network.

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Synchronous machines, widely used in energy generation systems, require constant voltage and frequency to obtain good quality of energy. However, for large load variati- ons, it is difficult to maintain outputs on nominal values due to parametric uncertainties, nonlinearities and coupling among variables. Then, we propose to apply the Dual Mode Adaptive Robust Controller (DMARC) in the field flux control loop, replacing the tradi- tional PI controller. The DMARC links a Model Reference Adaptive Controller (MRAC) and a Variable Structure Model Reference Adaptive Controller (VS-MRAC), incorpora- ting transient performance advantages from VS-MRAC and steady state properties from MRAC. Moreover, simulation results are included to corroborate the theoretical studies.

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A typical electrical power system is characterized by centr alization of power gene- ration. However, with the restructuring of the electric sys tem, this topology is changing with the insertion of generators in parallel with the distri bution system (distributed gene- ration) that provides several benefits to be located near to e nergy consumers. Therefore, the integration of distributed generators, especially fro m renewable sources in the Brazi- lian system has been common every year. However, this new sys tem topology may result in new challenges in the field of the power system control, ope ration, and protection. One of the main problems related to the distributed generati on is the islanding formation, witch can result in safety risk to the people and to the power g rid. Among the several islanding protection techniques, passive techniques have low implementation cost and simplicity, requiring only voltage and current measuremen ts to detect system problems. This paper proposes a protection system based on the wavelet transform with overcur- rent and under/overvoltage functions as well as infomation of fault-induced transients in order to provide a fast detection and identification of fault s in the system. The propo- sed protection scheme was evaluated through simulation and experimental studies, with performance similar to the overcurrent and under/overvolt age conventional methods, but with the additional detection of the exact moment of the fault.

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A Wireless Sensor Network (WSN) consists of distributed devices in an area in order to monitor physical variables such as temperature, pressure, vibration, motion and environmental conditions in places where wired networks would be difficult or impractical to implement, for example, industrial applications of difficult access, monitoring and control of oil wells on-shore or off-shore, monitoring of large areas of agricultural and animal farming, among others. To be viable, a WSN should have important requirements such as low cost, low latency, and especially low power consumption. However, to ensure these requirements, these networks suffer from limited resources, and eventually being used in hostile environments, leading to high failure rates, such as segmented routing, mes sage loss, reducing efficiency, and compromising the entire network, inclusive. This work aims to present the FTE-LEACH, a fault tolerant and energy efficient routing protocol that maintains efficiency in communication and dissemination of data.This protocol was developed based on the IEEE 802.15.4 standard and suitable for industrial networks with limited energy resources

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The stabilization of energy supply in Brazil has been a challenge for the operation of the National Interconnected System in face of hydrological and climatic variations. Thermoelectric plants have been used as an emergency source for periods of water scarcity. The utilization of fossil fuels, however, has elevated the cost of electricity. On the other hand, offshore wind energy has gained importance in the international context and is competitive enough to become a possibility for future generation in Brazil. In this scenario, the main goal of this thesis was to investigate the magnitude and distribution of offshore wind resources, and also verify the possibilities of complementing hydropower. A data series of precipitation from the Climatic Research Unit (CRU) Blended Sea Winds from the National Climatic Data Center (NCDC/NOAA) were used. According to statistical criteria, three types of complementarity were found in the Brazilian territory: hydro × hydro, wind × wind and hydro × wind. It was noted a significant complementarity between wind and hydro resources (r = -0.65), mainly for the hydrographical basins of the southeast and central regions with Northeastern Brazil winds. To refine the extrapolation of winds over the ocean, a method based on the Monin-Obukhov theory was used to model the stability of the atmospheric boundary layer. Objectively Analyzed Air-Sea Flux (OAFLUX) datasets for heat flux, temperature and humidity, and also sea level pressure data from NCEP/NCAR were used. The ETOPO1 from the National Geophysical Data Center (NGDC/NOAA) provided bathymetric data. It was found that shallow waters, between 0-20 meters, have a resource estimated at 559 GW. The contribution of wind resources to hydroelectric reservoir operation was investigated with a simplified hybrid wind-hydraulic model, and reservoir level, inflow, outflow and turbine production data. It was found that the hybrid system avoids drought periods, continuously saving water from reservoirs through wind production. Therefore, from the results obtained, it is possible to state that the good winds from the Brazilian coast can, besides diversifying the electric matrix, stabilize the hydrological fluctuations avoiding rationing and blackouts, reducing the use of thermal power plants, increasing the production cost and emission of greenhouse gases. Public policies targeted to offshore wind energy will be necessary for its full development.

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The Ultimatum Game is a methodology of the Game Theory that intends to investigate the individuals cooperative behavior in situations of resources division. Studies have shown that half of the subjects don’t accept unfair division of resources, and prefer to bear a momentary cost to revenge the deceivers. However, people who have assertiveness impairment, such as social phobic individuals, could have some difficulties to reject unfair offer division resource, especially in situations that cause over anxiety, like being in the presence of an individual considered to be in a high hierarchical level. A negative perception about his own worth can also make the person thinks that he does not deserve a fair division. These individuals also have a strong desire to convey a positive impression to the others, which could cause them to be more generous in a resource division. The aim of this study was to verify, through the Ultimatum Game, if social anxiety individuals would accept more high confederate’s unfair offers that low confederate’s unfair offers; and if they would be more generous in goods division, in the same game, when compared to individuals without social anxiety. Ninety-five (95) college students participated in this study answering the Social Phobia Inventory, the Factorial Scale of Extroversion, socio-demographic questionnaire, situational anxiety scale and, finally, the Ultimatum Game in four rounds (1st and 3rd – confederate representing high or low ranking using an unfair proposal; 2nd – confederate without social status using fair proposal; 4th – subject’s research proposes the offer). The results showed a significant negative correlation between social anxiety and haughtiness, and social anxiety and assertiveness, and a significant positive correlation between social anxiety and situational anxiety. There was no significant difference in situational anxiety due to the status for anxious individuals. Also we found no significant difference in the amount of donated goods, showing that generous behavior does not differ between groups. Finally, the social status did not influence the decision in response to the game for anxious individuals. These results corroborate to other studies that show the relationship between social anxiety and assertiveness, and social anxiety and negative self-perception capability and value (low haughtiness). As show the results of situational anxiety scale, the high status stimulus was not perceived as threatening to the individual, which may have affected his answer in the game. The results for the Ultimatum Game follow the same direction as the acceptance rate for unfair proposals (approximately 50%) in studies with non-clinical sample.

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The Ultimatum Game is a methodology of the Game Theory that intends to investigate the individuals cooperative behavior in situations of resources division. Studies have shown that half of the subjects don’t accept unfair division of resources, and prefer to bear a momentary cost to revenge the deceivers. However, people who have assertiveness impairment, such as social phobic individuals, could have some difficulties to reject unfair offer division resource, especially in situations that cause over anxiety, like being in the presence of an individual considered to be in a high hierarchical level. A negative perception about his own worth can also make the person thinks that he does not deserve a fair division. These individuals also have a strong desire to convey a positive impression to the others, which could cause them to be more generous in a resource division. The aim of this study was to verify, through the Ultimatum Game, if social anxiety individuals would accept more high confederate’s unfair offers that low confederate’s unfair offers; and if they would be more generous in goods division, in the same game, when compared to individuals without social anxiety. Ninety-five (95) college students participated in this study answering the Social Phobia Inventory, the Factorial Scale of Extroversion, socio-demographic questionnaire, situational anxiety scale and, finally, the Ultimatum Game in four rounds (1st and 3rd – confederate representing high or low ranking using an unfair proposal; 2nd – confederate without social status using fair proposal; 4th – subject’s research proposes the offer). The results showed a significant negative correlation between social anxiety and haughtiness, and social anxiety and assertiveness, and a significant positive correlation between social anxiety and situational anxiety. There was no significant difference in situational anxiety due to the status for anxious individuals. Also we found no significant difference in the amount of donated goods, showing that generous behavior does not differ between groups. Finally, the social status did not influence the decision in response to the game for anxious individuals. These results corroborate to other studies that show the relationship between social anxiety and assertiveness, and social anxiety and negative self-perception capability and value (low haughtiness). As show the results of situational anxiety scale, the high status stimulus was not perceived as threatening to the individual, which may have affected his answer in the game. The results for the Ultimatum Game follow the same direction as the acceptance rate for unfair proposals (approximately 50%) in studies with non-clinical sample.