1000 resultados para Sistemas elétricos de distribuição


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O propósito deste estudo foi contribuir para a análise da epidemiologia da oclusão dentária na infância e discutir a implicação para os sistemas de saúde, examinando dados de prevalência de uma amostra probabilística (n=985) da população de 5 e 12 anos de idade na cidade de São Paulo, Brasil (1996); e estudos epidemiológicos transversais publicados nos últimos 70 anos. A prevalência na cidade, cresceu de 49,0 ± 4,5 por cento na dentição decídua para 71,3 ± 3,9 por cento na dentição permanente (p<0,001), sendo que a chance de ocorrência de oclusopatia moderada/severa foi quase duas vezes maior na segunda dentição (OR=1,87; IC95 por cento =1,43-2,45; pde cárie acima das metas da OMS para o ano 2000 mostrou associação positiva com a severidade do dano (OR=1,51; IC95s por cento =1,15-1,99; p<0,003). Análise de regressão logística múltipla mostrou que o risco estimado da população portadora de dentição permanente e com experiência de cárie acima dessas metas apresentar oclusopatia moderada/severa se elevou de 22 por cento para 50 por cento . Sexo, tipo de escola (pública e privada) e diferenças étnicas entre brancos e pardos não influenciaram essa distribuição. O exame da literatura através de meta-análise indicou que a prevalência dos problemas oclusais foi duas vezes maior na dentição permanente quando comparada às dentições decídua/mista. Tanto a realização de estudos longitudinais quanto de levantamentos e triagens para a identificação e o tratamento dos casos mais severos, não apenas no período da dentição permanente, mas também nas dentições decídua/mista, combinado à introdução de ações de proteção específica em programas materno-infantis direcionadas ao desenvolvimento oro-facial dos zero aos 6 anos são medidas que devem ser consideradas no planejamento estratégico e normativo dos sistemas de saúde. Métodos de intervenção em saúde pública devem ser pesquisados e implementados o mais precocemente possível para aumentar a proporção da população com oclusão normal e reduzir o percentual de oclusopatia moderada/severa.

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As infiltrações com origem direta e indireta em eventos pluviométricos são os principais responsáveis por múltiplos problemas nos sistemas de drenagem, tais como, entrada da rede em carga, com possíveis extravasamentos para as ruas, falta de capacidade de tratamento nas devidas estações e aumento da poluição nos meios recetores. Deste modo, pretendeu-se efetuar a caraterização e o controlo das afluências indevidas no sistema de drenagem de águas residuais da vila de Lorvão, recorrendo à construção de um Sistema de Informação Geográfica onde se armazenou toda a informação cadastral recolhida. Desenvolveu-se, ainda, uma estratégia que permitiu aferir o desempenho deste sistema no que respeita aos caudais de infiltração, através da medição dos caudais afluentes à Estação de Tratamento de Águas Residuais, dos dados de distribuição de água, dos dados do reservatório abastecedor de água e da precipitação ocorrida.

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O presente trabalho tem como base um estágio na entidade gestora INOVA-EM-S.A. a fim de reduzir a água não faturada. O estudo forcar-se-á especificamente nas perdas de água, às quais se dará uma maior importância às perdas reais. Este tema assume grande importância, notando-se cada vez mais, a consciência para este problema que afeta as entidades gestoras de todo o mundo. A nível nacional, a entidade reguladora - ERSAR define como principal alvo o valor de 20% de água não faturada, valor este que se tem revelado bastante inferior ao verificado para a realidade de várias entidades gestoras. Numa primeira fase, por forma a reduzir as perdas de água, será analisado todo o sistema de abastecimento de água do concelho de Cantanhede nomeadamente reservatórios, condutas, consumidores e os respetivos consumos. Posteriormente serão analisados todos os dados dos consumidores, bem como os das ZMCs presentes, resultando na elaboração de indicadores. Estes indicadores serão importantes para a tomada de decisão sobre qual ZMC intervir, e também aqui será essencial a análise dos caudais mínimos noturnos resultante do processo de telemetria. A escolha da zona de medição crítica será consequência dos valores referentes aos indicadores anteriormente referidos, assim como do tempo necessário para o estudo e todo o processo de atuação nesta ZMC. A ZMC (Bolho) escolhida será alvo de campanhas de deteção e intervenção, com a finalidade da redução das perdas reais, entretanto, paralelamente a este processo, será revisto todo o parque de contadores procedendo à verificação e mesmo à substituição de alguns contadores, combatendo assim parte das perdas aparentes. Estes processos serão acompanhados com a monitorização constante permitindo assim a verificação das medidas tomadas. Posteriormente serão abandonadas as intervenções, dando lugar a intervenções pontuais a realizar apenas quando necessário, mantendo a monitorização constante durante este período. Verificou-se que os indicadores, bem como os caudais mínimos noturnos subiram de forma considerável. Mais tarde será realizada uma nova campanha de deteção de fugas, desta vez não tão exaustiva como a anterior. Esta campanha será realizada com vista a analisar o estado da ZMC depois de realizado todo este processo exaustivo de intervenções. Como resultado desta segunda campanha serão identificados novos locais com roturas, locais que anteriormente na primeira campanha não foram destacados como locais a intervir por não apresentarem indícios de rotura ou fuga de água.

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The purpose of this research is to analyze different daylighting systems in schools in the city of Natal/RN. Although with the abundantly daylight available locally, there are a scarce and diffuse architectural recommendations relating sky conditions, dimensions of daylight systems, shading, fraction of sky visibility, required illuminance, glare, period of occupation and depth of the lit area. This research explores different selected apertures systems to explore the potential of natural light for each system. The method has divided into three phases: The first phase is the modeling which involves the construction of three-dimensional model of a classroom in Sketchup software 2014, which is featured in follow recommendations presented in the literature to obtain a good quality of environmental comfort in school settings. The second phase is the dynamic performance computer simulation of the light through the Daysim software. The input data are the climate file of 2009 the city of Natal / RN, the classroom volumetry in 3ds format with the assignment of optical properties of each surface, the sensor mapping file and the user load file . The results produced in the simulation are organized in a spreadsheet prepared by Carvalho (2014) to determine the occurrence of useful daylight illuminance (UDI) in the range of 300 to 3000lux and build graphics illuminance curves and contours of UDI to identify the uniformity of distribution light, the need of the minimum level of illuminance and the occurrence of glare.

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There are several abiotic factors reported in the literature as regulators of the distribution of fish species in marine environments. Among them stand out structural complexity of habitat, benthic composition, depth and distance from the coast are usually reported as positive influencers in the diversity of difentes species, including reef fish. These are dominant elements in reef systems and considered high ecological and socioeconomic importance. Understanding how the above factors influence the distribution and habitat use of reef fish communities are important for their management and conservation. Thus, this study aims to evaluate the influence of these variables on the community of reef fishes along an environmental gradient of depth and distance from shore base in sandstone reefs in the coast of state of Rio Grande do Norte, Brazil. These variables are also used for creating a simple predictive model reef fish biomass for the environment studied. Data collection was performed through visual surveys in situ, and recorded environmental data (structural complexity of habitat, type of coverage of the substrate, benthic invertebrates) and ecological (wealth, abundance and reef fish size classes). As a complement, information on the diet were raised through literature and the biomass was estimated from the length-weight relationship of each species. Overall, the reefs showed a low coverage by corals and the Shallow reefs, Intermediate I and II dominated by algae and the Funds by algae and sponges. The complexity has increased along the gradient and positively influenced the species richness and abundance. Both attributes influenced in the structure of the reef fish community, increasing the richness, abundance and biomass of fish as well as differentiating the trophic structure of the community along the depth gradient and distance from the coast. Distribution and use of habitat by recifas fish was associated with food availability. The predictor model identified depth, roughness and coverage for foliose algae, calcareous algae and soft corals as the most significant variables influencing in the biomass of reef fish. In short, the description and understanding of these patterns are important steps to elucidate the ecological processes. In this sense, our approach provides a new understanding of the structure of the reef fish community of Rio Grande do Norte, allowing understand a part of a whole and assist future monitoring actions, evaluation, management and conservation of these and other reefs of Brazil.

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Binary systems are key environments to study the fundamental properties of stars. In this work, we analyze 99 binary systems identified by the CoRoT space mission. From the study of the phase diagrams of these systems, our sample is divided into three groups: those whose systems are characterized by the variability relative to the binary eclipses; those presenting strong modulations probably due to the presence of stellar spots on the surface of star; and those whose systems have variability associated with the expansion and contraction of the surface layers. For eclipsing binary stars, phase diagrams are used to estimate the classification in regard to their morphology, based on the study of equipotential surfaces. In this context, to determine the rotation period, and to identify the presence of active regions, and to investigate if the star exhibits or not differential rotation and study stellar pulsation, we apply the wavelet procedure. The wavelet transform has been used as a powerful tool in the treatment of a large number of problems in astrophysics. Through the wavelet transform, one can perform an analysis in time-frequency light curves rich in details that contribute significantly to the study of phenomena associated with the rotation, the magnetic activity and stellar pulsations. In this work, we apply Morlet wavelet (6th order), which offers high time and frequency resolution and obtain local (energy distribution of the signal) and global (time integration of local map) wavelet power spectra. Using the wavelet analysis, we identify thirteen systems with periodicities related to the rotational modulation, besides the beating pattern signature in the local wavelet map of five pulsating stars over the entire time span.

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Binary systems are key environments to study the fundamental properties of stars. In this work, we analyze 99 binary systems identified by the CoRoT space mission. From the study of the phase diagrams of these systems, our sample is divided into three groups: those whose systems are characterized by the variability relative to the binary eclipses; those presenting strong modulations probably due to the presence of stellar spots on the surface of star; and those whose systems have variability associated with the expansion and contraction of the surface layers. For eclipsing binary stars, phase diagrams are used to estimate the classification in regard to their morphology, based on the study of equipotential surfaces. In this context, to determine the rotation period, and to identify the presence of active regions, and to investigate if the star exhibits or not differential rotation and study stellar pulsation, we apply the wavelet procedure. The wavelet transform has been used as a powerful tool in the treatment of a large number of problems in astrophysics. Through the wavelet transform, one can perform an analysis in time-frequency light curves rich in details that contribute significantly to the study of phenomena associated with the rotation, the magnetic activity and stellar pulsations. In this work, we apply Morlet wavelet (6th order), which offers high time and frequency resolution and obtain local (energy distribution of the signal) and global (time integration of local map) wavelet power spectra. Using the wavelet analysis, we identify thirteen systems with periodicities related to the rotational modulation, besides the beating pattern signature in the local wavelet map of five pulsating stars over the entire time span.

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Sandstone-type reservoir rocks are commonly responsible for oil accumulation. The wettability is an important parameter for the physical properties of the container, since it interferes in characteristics such as relative permeability to the aqueous phase, residual oil distribution in the reservoir, operating characteristics with waterflood and recovery of crude oil. This study applied different types of microemulsion systems - MES - in sandstone reservoirs and evaluated their influences on wettability and residual oil recovery. For this purpose, four microemulsion were prepared by changing the nature of ionic surfactants (ionic and nonionic). Microemulsions could then be characterized by surface tension analysis, density, particle diameter and viscosity in the temperature range 30° C to 70° C. The studied oil was described as light and the sandstone rock was derived from the Botucatu formation. The study of the influence of microemulsion systems on sandstone wettability was performed by contact angle measurements using as parameters the rock treatment time with the MES and the time after the brine surface contact by checking the angle variation behavior. In the study results, the rock was initially wettable to oil and had its wettability changed to mixed wettability after treatment with MES, obtaining preference for water. Regarding rock-MES contact time, it was observed that the rock wettability changed more when the contact time between the surface and the microemulsion systems was longer. It was also noted only a significant reduction for the first 5 minutes of interaction between the treated surface and brine. The synthesized anionic surfactant, commercial cationic, commercial anionic and commercial nonionic microemulsion systems presented the best results, respectively. With regard to enhanced oil recovery performance, all systems showed a significant percentage of recovered oil, with the anionic systems presenting the best results. A percentage of 80% recovery was reached, confirming the wettability study results, which pointed the influence of this property on the interaction of fluids and reservoir rock, and the ability of microemulsion systems to perform enhanced oil recovery in sandstone reservoirs.

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Sandstone-type reservoir rocks are commonly responsible for oil accumulation. The wettability is an important parameter for the physical properties of the container, since it interferes in characteristics such as relative permeability to the aqueous phase, residual oil distribution in the reservoir, operating characteristics with waterflood and recovery of crude oil. This study applied different types of microemulsion systems - MES - in sandstone reservoirs and evaluated their influences on wettability and residual oil recovery. For this purpose, four microemulsion were prepared by changing the nature of ionic surfactants (ionic and nonionic). Microemulsions could then be characterized by surface tension analysis, density, particle diameter and viscosity in the temperature range 30° C to 70° C. The studied oil was described as light and the sandstone rock was derived from the Botucatu formation. The study of the influence of microemulsion systems on sandstone wettability was performed by contact angle measurements using as parameters the rock treatment time with the MES and the time after the brine surface contact by checking the angle variation behavior. In the study results, the rock was initially wettable to oil and had its wettability changed to mixed wettability after treatment with MES, obtaining preference for water. Regarding rock-MES contact time, it was observed that the rock wettability changed more when the contact time between the surface and the microemulsion systems was longer. It was also noted only a significant reduction for the first 5 minutes of interaction between the treated surface and brine. The synthesized anionic surfactant, commercial cationic, commercial anionic and commercial nonionic microemulsion systems presented the best results, respectively. With regard to enhanced oil recovery performance, all systems showed a significant percentage of recovered oil, with the anionic systems presenting the best results. A percentage of 80% recovery was reached, confirming the wettability study results, which pointed the influence of this property on the interaction of fluids and reservoir rock, and the ability of microemulsion systems to perform enhanced oil recovery in sandstone reservoirs.

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Software bug analysis is one of the most important activities in Software Quality. The rapid and correct implementation of the necessary repair influence both developers, who must leave the fully functioning software, and users, who need to perform their daily tasks. In this context, if there is an incorrect classification of bugs, there may be unwanted situations. One of the main factors to be assigned bugs in the act of its initial report is severity, which lives up to the urgency of correcting that problem. In this scenario, we identified in datasets with data extracted from five open source systems (Apache, Eclipse, Kernel, Mozilla and Open Office), that there is an irregular distribution of bugs with respect to existing severities, which is an early sign of misclassification. In the dataset analyzed, exists a rate of about 85% bugs being ranked with normal severity. Therefore, this classification rate can have a negative influence on software development context, where the misclassified bug can be allocated to a developer with little experience to solve it and thus the correction of the same may take longer, or even generate a incorrect implementation. Several studies in the literature have disregarded the normal bugs, working only with the portion of bugs considered severe or not severe initially. This work aimed to investigate this portion of the data, with the purpose of identifying whether the normal severity reflects the real impact and urgency, to investigate if there are bugs (initially classified as normal) that could be classified with other severity, and to assess if there are impacts for developers in this context. For this, an automatic classifier was developed, which was based on three algorithms (Näive Bayes, Max Ent and Winnow) to assess if normal severity is correct for the bugs categorized initially with this severity. The algorithms presented accuracy of about 80%, and showed that between 21% and 36% of the bugs should have been classified differently (depending on the algorithm), which represents somewhere between 70,000 and 130,000 bugs of the dataset.

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Universities are institutions that generate and manipulate large amounts of data as a result of the multiple functions they perform, of the amount of involved professionals and students they attend. Information gathered from these data is used, for example, for operational activities and to support decision-making by managers. To assist managers in accomplishing their tasks, the Information Systems (IS) are presented as tools that offer features aiming to improve the performance of its users, assist with routine tasks and provide support to decision-making. The purpose of this research is to evaluate the influence of the users features and of the task in the success of IS. The study is of a descriptive-exploratory nature, therefore, the constructs used to define the conceptual model of the research are known and previously validated. However, individual features of users and of the task are IS success antecedents. In order to test the influence of these antecedents, it was developed a decision support IS that uses the Multicriteria Decision Aid Constructivist (MCDA-C) methodology with the participation and involvement of users. The sample consisted of managers and former managers of UTFPR Campus Pato Branco who work or have worked in teaching activities, research, extension and management. For data collection an experiment was conducted in the computer lab of the Campus Pato Branco in order to verify the hypotheses of the research. The experiment consisted of performing a distribution task of teaching positions between the academic departments using the IS developed. The task involved decision-making related to management activities. The data that fed the system used were real, from the Campus itself. A questionnaire was answered by the participants of the experiment in order to obtain data to verify the research hypotheses. The results obtained from the data analysis partially confirmed the influence of the individual features in IS success and fully confirmed the influence of task features. The data collected failed to support significant ratio between the individual features and the individual impact. For many of the participants the first contact with the IS was during the experiment, which indicates the lack of experience with the system. Regarding the success of IS, the data revealed that there is no significance in the relationship between Information Quality (IQ) and Individual Impact (II). It is noteworthy that the IS used in the experiment is to support decision-making and the information provided by this system are strictly quantitative, which may have caused some conflict in the analysis of the criteria involved in the decision-making process. This is because the criteria of teaching, research, extension and management are interconnected such that one reflects on another. Thus, the opinion of the managers does not depend exclusively on quantitative data, but also of knowledge and value judgment that each manager has about the problem to be solved.

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The municipal management in any country of the globe requires planning and allocation of resources evenly. In Brazil, the Law of Budgetary Guidelines (LDO) guides municipal managers toward that balance. This research develops a model that seeks to find the balance of the allocation of public resources in Brazilian municipalities, considering the LDO as a parameter. For this using statistical techniques and multicriteria analysis as a first step in order to define allocation strategies, based on the technical aspects arising from the municipal manager. In a second step, presented in linear programming based optimization where the objective function is derived from the preference of the results of the manager and his staff. The statistical representation is presented to support multicriteria development in the definition of replacement rates through time series. The multicriteria analysis was structured by defining the criteria, alternatives and the application of UTASTAR methods to calculate replacement rates. After these initial settings, an application of linear programming was developed to find the optimal allocation of enforcement resources of the municipal budget. Data from the budget of a municipality in southwestern Paraná were studied in the application of the model and analysis of results.

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Em Portugal o “Sistema Nacional de Sangue” subsiste com base numa cadeia de abastecimento de sangue assente em dádivas provenientes 100% de Dadores Voluntários não Remunerados, com um serviço nacional de sangue de base exclusivamente pública. O seu modelo organizacional assenta numa estrutura de âmbito nacional com funções de regulação, fiscalização, produção e distribuição de sangue e componentes sanguíneos às organizações de saúde públicas e privadas. Em complemento a esta rede de abastecimento existem ainda outras fontes de abastecimento, como os hospitais licenciados e outras instituições, que também procedem a todas as actividades de colheita, processamento e validação para uso final de componentes sanguíneos. Nestas situações a produção de componentes sanguíneos é realizada numa perspectiva de auto-suficiência, local ou regional, um dos princípios fundamentais de todos os serviços nacionais de sangue. Esta dissertação pretende contribuir para o conhecimento do sistema de abastecimento e consumo de sangue, aproveitando para colocar algumas questões em relação ao pode significar a gestão eficiente e eficaz da cadeia de abastecimento de sangue. A gestão eficaz da cadeia de abastecimento passa pelo conhecimento profundo da sua população de dadores, saber quem são, o que os move, quais os seus comportamentos perante a dádiva. Só assim é possível intervir eficazmente e adequar as estratégias mais eficazes à sua motivação e fidelização dádiva regular. Assim, foi efectuado um caso de estudo relativo à população de dadores do Serviço de ImunoHemoterapia do Centro Hospitalar de Vila Nova de Gaia- Espinho (CHVNG- Espinho), por forma a procurar oportunidades de melhoria nas estratégias de angariação de dadores e promoção da dádiva de sangue, acrescentando valor ao serviço e ao CHVNG-Espinho.

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This work proposes to adjust the Notification Oriented Paradigm (NOP) so that it provides support to fuzzy concepts. NOP is inspired by elements of imperative and declarative paradigms, seeking to solve some of the drawbacks of both. By decomposing an application into a network of smaller computational entities that are executed only when necessary, NOP eliminates the need to perform unnecessary computations and helps to achieve better logical-causal uncoupling, facilitating code reuse and application distribution over multiple processors or machines. In addition, NOP allows to express the logical-causal knowledge at a high level of abstraction, through rules in IF-THEN format. Fuzzy systems, in turn, perform logical inferences on causal knowledge bases (IF-THEN rules) that can deal with problems involving uncertainty. Since PON uses IF-THEN rules in an alternative way, reducing redundant evaluations and providing better decoupling, this research has been carried out to identify, propose and evaluate the necessary changes to be made on NOP allowing to be used in the development of fuzzy systems. After that, two fully usable materializations were created: a C++ framework, and a complete programming language (LingPONFuzzy) that provide support to fuzzy inference systems. From there study cases have been created and several tests cases were conducted, in order to validate the proposed solution. The test results have shown a significant reduction in the number of rules evaluated in comparison to a fuzzy system developed using conventional tools (frameworks), which could represent an improvement in performance of the applications.

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In this work, was studied the formation of a composite of the refractory metal niobium with copper, through the process of high-energy milling and liquid phase sintering. The HEM can be used to synthesize composite powders with high homogeneity and fine size particle distribution. It may also produce the solid solubility in immiscible systems such as Nb-Cu, or extend the solubility of systems with limited solubility. Therefore, in the immiscible system Cu-Nb, the high-energy milling was successfully used to obtain the composite powder particles. Initially, the formation of composite particles during the HEM and the effect of preparation technique on the microstructure of the material was evaluated. Four loads of Nb and Cu powders containing 20%wt Cu were synthesized by MAE in a planetary type ball mill under different periods of grinding. The influence of grinding time on the metal particles is evaluated during the process by the withdrawal of samples at intermediate times of milling. After compaction under different forces, the samples were sintered in a vacuum furnace. The liquid phase sintering of these samples prepared by HEM produced a homogeneous and fine grained. The composite particles forming the sintered samples are the addition of a hard phase (Nb) with a high melting point, and a ductile phase (Cu) with low melting point and high thermal and electrical conductivities. Based on these properties, the Nb-Cu system is a potential material for many applications, such as electrical contacts, welding electrodes, coils for generating high magnetic fields, heat sinks and microwave absorbers, which are coupled to electronic devices. The characterization techniques used in this study, were laser granulometry, used to evaluate the homogeneity and particle size, and the X-ray diffraction, in the phase identification and to analyze the crystalline structure of the powders during milling. The morphology and dispersion of the phases in the composite powder particles, as well the microstructures of the sintered samples, were observed by scanning electron microscopy (SEM). Subsequently, the sintered samples are evaluated for density and densification. And finally, they were characterized by techniques of measuring the electrical conductivity and microhardness, whose properties are analyzed as a function of the parameters for obtaining the composite