999 resultados para Redes de distribuição, Árvore de Steiner, Coleta de prêmios


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The aim of this approach is to describe the design and construction of a low-cost automated water sampler prototype. In recent years, there is an increasing need on the use of automated equipments for hydro climatic variables to be use in urban and rural environments. Such devices are always used to provide measured information which is of crucial importance on the development of water resources strategies at watershed scale. Actually, many research and water public institutions have been using these kinds of equipments. In most of the cases, automated equipments are expensive and need to be imported, generating a situation of technologic dependency. The prototype is based on an electronic system which controls a peristaltic pump functioning, five solenoid valves and an ultrasonic sensor connected to a datalloger. An interface with the user allows communication with a PC, when the equipment functioning parameters can be provided. The equipment has a hydraulic module composed by a 12V peristaltic pump connected to a distribution circuit composed by five solenoid valves, one of them being used to clean the circuit before each sampling procedure. Samples are collected by four 1.95 polyethylene bottles. The sampler body was made of acrylic material, with a cylindrical shape, and dimensions 0.72 m and 0.38 m height and diameter, respectively. The weight of the equipment without samples is approximately 15 kg, which infers to its portability. The prototype development total cost budget was approximately US$ 1,560.00. Laboratory tests aimed to evaluate the equipment performance and functioning demonstrated satisfactory results

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The aim of this study is to characterize and evaluate the Macro System of Regional Water Distribution Natal North (RNN) and Southern Regional Natal (RNS), covering 35% and 65% respectively of the Natal-RN City. The terms of the quality and quantity of water (surface and groundwater) were also evaluated in order to adjust the parameters that contribute to proper distribution and control in water reserves. The methodology of the work took place from collecting volumetric data of production capacity and distribution of the two treatment plants for Regional as well as the flow rates of wells. Yet the quantitative capacity of reservation, distribution and consumption of the main reservoirs, population numbers and consumption of members neighborhoods were collected. Data were tabulated and used in computational simulator EPANET to diagnose possible through the water balance, the offers and demands on the water supply system in the neighborhoods of the capital, linking them to specific distribution points. We also evaluated the wells in the levels of nitrate in water consumed. As a result it was found that some neighborhoods in the South Regional Natal, was ranked as critical supply situation: City of Hope, Lagoa Nova and Nova Descoberta, where demand exceeds supply. While in most Northern Regional Natal present deficiency in the supply system as: Lagoa Azul, the Parque dos Coqueiros, igapó, Amarante and Salinas. The rates of nitrate in the city were significant, but manageable with corrective and preventive measures. The averages were 12 mg /l-N in Candelária, 10 mg/l-N in Lagoa Nova, 9 mg/l-N in Satelite, 20 mg/l-N in Gramore and 15 mg/l-N in N. Sra. Apresentação. Therefore proper distribution of water abstracted and implementation of quality control ensures the supply required by the system, associated with preservation of Water Resources of the Metropolitan Region of Natal

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In this work we study a connection between a non-Gaussian statistics, the Kaniadakis statistics, and Complex Networks. We show that the degree distribution P(k)of a scale free-network, can be calculated using a maximization of information entropy in the context of non-gaussian statistics. As an example, a numerical analysis based on the preferential attachment growth model is discussed, as well as a numerical behavior of the Kaniadakis and Tsallis degree distribution is compared. We also analyze the diffusive epidemic process (DEP) on a regular lattice one-dimensional. The model is composed of A (healthy) and B (sick) species that independently diffusive on lattice with diffusion rates DA and DB for which the probabilistic dynamical rule A + B → 2B and B → A. This model belongs to the category of non-equilibrium systems with an absorbing state and a phase transition between active an inactive states. We investigate the critical behavior of the DEP using an auto-adaptive algorithm to find critical points: the method of automatic searching for critical points (MASCP). We compare our results with the literature and we find that the MASCP successfully finds the critical exponents 1/ѵ and 1/zѵ in all the cases DA =DB, DA DB. The simulations show that the DEP has the same critical exponents as are expected from field-theoretical arguments. Moreover, we find that, contrary to a renormalization group prediction, the system does not show a discontinuous phase transition in the regime o DA >DB.

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In this thesis we investigate physical problems which present a high degree of complexity using tools and models of Statistical Mechanics. We give a special attention to systems with long-range interactions, such as one-dimensional long-range bondpercolation, complex networks without metric and vehicular traffic. The flux in linear chain (percolation) with bond between first neighbor only happens if pc = 1, but when we consider long-range interactions , the situation is completely different, i.e., the transitions between the percolating phase and non-percolating phase happens for pc < 1. This kind of transition happens even when the system is diluted ( dilution of sites ). Some of these effects are investigated in this work, for example, the extensivity of the system, the relation between critical properties and the dilution, etc. In particular we show that the dilution does not change the universality of the system. In another work, we analyze the implications of using a power law quality distribution for vertices in the growth dynamics of a network studied by Bianconi and Barabási. It incorporates in the preferential attachment the different ability (fitness) of the nodes to compete for links. Finally, we study the vehicular traffic on road networks when it is submitted to an increasing flux of cars. In this way, we develop two models which enable the analysis of the total flux on each road as well as the flux leaving the system and the behavior of the total number of congested roads

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In this thesis we deal with a class of composed networks that are formed by two tree networks, TP and TA, whose end points touches each other through a bipartite network BPA. We explore this network using a functional approach. We are interested in what extend the topology, or the structure, of TX (X = A or P) determines the links of BPA. This composed structure is an useful model in evolutionary biology, where TP and TA are the phylogenetic trees of plants and animals that interact in an ecological community. We use in this thesis two cases of mutualist interactions: frugivory and pollinator networks. We analyse how the phylogeny of TX determines or is correlated with BPA using a Monte Carlo approach. We use the phylogenetic distance among elements that interact with a given species to construct an index κ that quantifies the influence of TX over BPA. The algorithm is based in the assumption that interaction matrices that follows a phylogeny of TX have a total phylogenetic distance smaller than the average distance of an ensemble of Monte Carlo realizations generated by an adequate shuffling data. We find that the phylogeny of animals species has an effect on the ecological matrix that is more marked than plant phylogeny

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In this work we analyse the implications of using a power law distribution of vertice's quality in the growth dynamics of a network studied by Bianconi anel Barabási. In particular, we start studying the random networks which characterize or are related to some real situations, for instance the tide movement. In this context of complex networks, we investigate several real networks, as well as we define some important concepts in the network studies. Furthermore, we present the first scale-free network model, which was proposed by Barabási et al., and a modified model studied by Bianconi and Barabási, where now the preferential attachment incorporates the different ability (fitness) of the nodes to compete for links. At the end, our results, discussions and conclusions are presented

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The competition for resources is one of the costs of group living. The scramble competition is considered an indirect type of competition, mainly associated with factors like group size and distribution of resources. Contest competition occurs when individuals compete directly for resources. In species that exibit this type of competition the establishment of dominance hierarchy can occur, resulting in differences on feeding and reproductive benefits for each member of the group. In these cases, aggressive and submissive behaviors are expected as a way to signal social status. The aim of this study was to investigate the effects of social hierarchy over food ingestion in Callithrix jacchus. Data recording was from September/2006 to March/2007, eight days by month, at Floresta Nacional de Açu do Instituto Chico Mendes de Biodiversidade. The observation time started at 05:00 AM and finished after the last animal was on the sleeptree. Analyses of aggressive interactions, behavioral profile and diet, reveals a lot of advantages for dominat animals in the study group. Dominant individuals had higher intake of animal matter that subordinates. The last ones, consumed fruits, exsudate and, eventually, explored itens that were not common to the diet. We suggest that dominance hiearchy enable the reproductive female to assure priority on access to food resources, a important caracteristc to supply tha costs to maintain tha high reproductive taxa of the specie. We also suggest that reproductive male, due to the participation on food transfer, had the forage efficience reduced

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The midline/intralaminar nuclei form a remarkable group of nuclei of the medial and dorsal thalamus. The midline nuclei, in rats, comprises the paratenial nuclei (PT), paraventricular (PV), intermediodorsal (IMD), reuniens (Re) and rhomboid (Rh). The intralaminar nuclei comprises the central medial (CM), paracentral (PC), central lateral (CL) and parafascicular (PF). Such nuclei have dense serotonergic innervation originating from the brainstem, especially from the so-called ascending activation system. These nuclei, in turn, send projections to various cortical and subcortical areas, specifically to limbic areas, which suggests the important role of this neurotransmitter in the limbic circuitry. The aim of this study was to characterize the distribution pattern and morphology of serotonin fibers in the nuclei of the midline and intralaminar thalamic of rocky cavy (Kerodon rupestris), a tipical rodent from brazilizan northeast. To reach this aim we used four rock cavies adults. Following the transcardially perfusion with paraformaldehyde and brain microtomy steps was performed immunohistochemistry for serotonin (5-HT), Nissl technique and subsequent achievement and image analysis to characterize the cytoarchitecture of these nuclei and the serotonergic fibers visualized. An analysis was made of Relative Optical Density (ROD) to semi-quantify the concentration of serotonin fibers in the areas of interest. Thus, we observed a cytoarchitectonic arrangement of these nuclei similar to that found in rats. In case of fibers distribution, those immunoreactive to 5-HT were presented in a higher concentration according as ROD in the midline nuclei relative to intralaminar; Re being the core which has a higher pixel value followed by the PV , Rh, IMD and PT. In intralaminar CL showed higher pixels, followed by nuclei CM, PC and PF. The serotonergic fibers were classified as number of varicosities and axon diameter, therefore find three types of fibers distributed through this nuclear complex: fibers rugous, granular and semi-granular. In PV fibers predominated rugous; in PT fibers predominated granular; IMD, CL and PF fibers were represented by semi-granular and Re, Rh, PC and CM fibers showed granular and semi-granular. Morphological characterization of serotonergic fibers and differences in density between the nuclei may suggest different patterns of synaptic organization of this neurotransmitter beyond confirming his large repertoire functional

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The general purpose of the study was the analysis of residents' participation in the program of door-by-door collection of recyclable residuals in Natal, Rio Grande do Norte. Even though the conception of such program by municipal managers was basically aimed at providing job opportunities and income for the collectors, the main objective of the investigation was to verify whether residents' participation could be attributed to their environmental commitment. Data collection involved three municipal districts and was performed in three stages, with complementary methodological strategies (observation, questionnaire, and interview), and characterized by selfevaluation, by residents, and hetero-evaluation, by collectors. Social, demographic, situational/contextual, and dispositional data were identified to help in the analysis of residents' adherence to the program. Separating and delivering recyclable residuals was the most frequent type of residents' participation, which demonstrates their low level of appropriation of decisions related to the program, taking part on it as passive agents. Two forms of motivation towards participating in the program were found: environmental and social. Despite the first being more frequent, it was associated to lack of environmental awareness related to the process, which may very well imply a mere reproduction of pro-environmental discourse. Motivation towards social issues was strongly connected to philanthropic forms of help. Knowledge was revealed as na important predictor for participation, as well as social networks, formed by neighbors, relatives and friends. Despite the social emphasis in the design of the program, it is possible to conclude that some residents also perceive its environmental benefits, possibly as consequence of a knowledge originated outside the program. Initiatives of environmental education should be promoted in order to minimize the allegation of lack of knowledge as justification for non-participation. Similarly, actions to put together municipal management and population would be welcome, to promote joint decisions towards sustainable styles of life

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O presente estudo discute a formação de Redes Sociais no cotidiano da Estratégia Saúde da Família, a partir de aportes da teoria sociológica sobre redes, interações, dádiva e reconhecimento. O objetivo geral é analisar as redes sociais locais em saúde a partir da interação de usuários e profissionais da Estratégia Saúde da Família na Unidade de Saúde de Ligéia, em Natal, RN. Seus objetivos específicos são: Mapear as redes sociais locais em saúde existentes no território adscrito; Identificar os tipos de interações cotidianas entre os sujeitos; Compreender a percepção dos sujeitos sobre o processo de formação de redes sociais a partir das interações. Caracteriza-se enquanto pesquisa qualitativa exploratória cujos sujeitos foram profissionais e usuários vinculados à referida unidade de saúde. Para a coleta de dados foram utilizadas entrevistas individuais semiestruturadas e debates em grupos focais, estimulados pela Metodologia de Análise de Redes do Cotidiano (MARES), pertinente para abordar a complexidade das relações sociais e mapear os diferentes conteúdos expressos e as formas de mobilização coletiva. A análise dos dados foi realizada através da Técnica de Análise Temática de Conteúdo, proposta por Minayo. Os resultados foram interpretados à luz das Teorias da Dádiva (Mauss) e do Reconhecimento (Honneth). Os sujeitos visualizaram: Rede Virtual (28,20%); Rede de Atenção à Saúde (25,64%); Redes de Usuários (17,95%); Rede Pessoal (10,26%); Conselho Comunitário (10,26%); Escolas (7,69%). Os participantes não perceberam os arranjos familiares enquanto Redes Sociais. Os tipos de interações sociais identificadas foram: Confrontação/Negociação (41.02%); Harmônicas (25,70%); Correlativas (17,90%); Definidas pela Organização (15,38%). A formação de redes sociais ocorre a partir de interações cotidianas entre pessoas, pela articulação inseparável de conteúdos e formas, catalisadas pelo contexto, experiência e cognição, valorizando a liberdade, a expressividade e a diversidade dos parceiros de significação. Foram encontradas duas categorias, na percepção dos sujeitos, sobre a formação de redes sociais do cotidiano: Diálogo e Encontro. Validamos e recomendamos o uso da metodologia MARES: Na formação, para despertar uma visão mais tolerante e humana de si e do outro; Na avaliação qualitativa dos serviços, por facilitar a reflexão sobre a prática e (re)organização do processo de trabalho; Na comunidade, para estimular movimentos sociais existentes ou emergentes. A aposta no circuito da dádiva e do reconhecimento recíproco, durante o trânsito nas redes sociais em saúde, pode ser capaz de tecer uma práxis transformadora, pela busca e alcance de confiança, respeito e estima, nos espaços de encontro entre usuários e profissionais da Estratégia Saúde da Família

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The Multiobjective Spanning Tree is a NP-hard Combinatorial Optimization problem whose application arises in several areas, especially networks design. In this work, we propose a solution to the biobjective version of the problem through a Transgenetic Algorithm named ATIS-NP. The Computational Transgenetic is a metaheuristic technique from Evolutionary Computation whose inspiration relies in the conception of cooperation (and not competition) as the factor of main influence to evolution. The algorithm outlined is the evolution of a work that has already yielded two other transgenetic algorithms. In this sense, the algorithms previously developed are also presented. This research also comprises an experimental analysis with the aim of obtaining information related to the performance of ATIS-NP when compared to other approaches. Thus, ATIS-NP is compared to the algorithms previously implemented and to other transgenetic already presented for the problem under consideration. The computational experiments also address the comparison to two recent approaches from literature that present good results, a GRASP and a genetic algorithms. The efficiency of the method described is evaluated with basis in metrics of solution quality and computational time spent. Considering the problem is within the context of Multiobjective Optimization, quality indicators are adopted to infer the criteria of solution quality. Statistical tests evaluate the significance of results obtained from computational experiments

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In this work we elaborate and discuss a Complex Network model which presents connectivity scale free probability distribution (power-law degree distribution). In order to do that, we modify the rule of the preferential attachment of the Bianconi-Barabasi model, including a factor which represents the similarity of the sites. The term that corresponds to this similarity is called the affinity, and is obtained by the modulus of the difference between the fitness (or quality) of the sites. This variation in the preferential attachment generates very interesting results, by instance the time evolution of the connectivity, which follows a power-law distribution ki / ( t t0 )fi, where fi indicates the rate to the site gain connections. Certainly this depends on the affinity with other sites. Besides, we will show by numerical simulations results for the average path length and for the clustering coefficient

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Neste trabalho, elaboramos e discutimos uma rede complexa sem escala, ou seja, uma rede cuja distribuição de conectividade segue uma lei de distribuição de potência. Nosso trabalho pode ser resumido da seguinte forma: Para efeito de didática vamos começar com redes aleatórias que estão relacionados com situações reais e artificiais, e depois comentar as redes livres de escala, como proposto por Barabási-Albert (BA). Depois disso, discutimos uma extensão deste modelo, onde Barabasi e Bianconi (BB) incluem a qualidade. Discutimos também o modelo de afinidade, ou seja, (Ver Almeida et al). Finalmente vamos mostrar o nosso modelo, uma extensão do modelo de afinidade dada por e apresentar os resultados correspondentes. Para realizar tal tarefa modificamos a regra de ligação preferencial do modelo de BB colocando um fator que apresenta o grau de probabilidade entre os sítios da rede. Esta quantidade é feita pela diferença entre a qualidade do novo sítio e a qualidade dos anteriores. Este novo parâmetro produz novos resultados interessantes: a distribuição que segue uma lei de especial de potência, expoente apropriado. A evolução temporal da conectividade do sítio também é calculada . Além disso, mostramos também, os resultados que foram obtidos, via simulação numérica, para o menor caminho médio e o coeficiente de agregação da rede gerada pelo nosso modelo, isto é, pelo modelo de afinidade.

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Currently the interest in large-scale systems with a high degree of complexity has been much discussed in the scientific community in various areas of knowledge. As an example, the Internet, protein interaction, collaboration of film actors, among others. To better understand the behavior of interconnected systems, several models in the area of complex networks have been proposed. Barabási and Albert proposed a model in which the connection between the constituents of the system could dynamically and which favors older sites, reproducing a characteristic behavior in some real systems: connectivity distribution of scale invariant. However, this model neglects two factors, among others, observed in real systems: homophily and metrics. Given the importance of these two terms in the global behavior of networks, we propose in this dissertation study a dynamic model of preferential binding to three essential factors that are responsible for competition for links: (i) connectivity (the more connected sites are privileged in the choice of links) (ii) homophily (similar connections between sites are more attractive), (iii) metric (the link is favored by the proximity of the sites). Within this proposal, we analyze the behavior of the distribution of connectivity and dynamic evolution of the network are affected by the metric by A parameter that controls the importance of distance in the preferential binding) and homophily by (characteristic intrinsic site). We realized that the increased importance as the distance in the preferred connection, the connections between sites and become local connectivity distribution is characterized by a typical range. In parallel, we adjust the curves of connectivity distribution, for different values of A, the equation P(k) = P0e