844 resultados para Many-valued logic


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Foundation Fieldbus Industrial networks are the high standard technology which allows users to create complex control logic and totally decentralized. Although being so advanced, they still have some limitations imposed by their own technology. Attempting to solve one of these limitations, this paper describes how to design a Fuzzy controller in a Foundation Fieldbus network using their basic elements of programming, the functional blocks, so that the network remains fully independent of other devices other than the same instruments that constitute it. Moreover, in this work was developed a tool that aids this process of building the Fuzzy controller, setting the internal parameters of functional blocks and informing how many and which blocks should be used for a given structure. The biggest challenge in creating this controller is exactly the choice of blocks and how to arrange them in order to effectuate the same functions of a Fuzzy controller implemented in other kind of environment. The methodology adopted was to divide each one of the phases of a traditional Fuzzy controller and then create simple structures with the functional blocks to implement them. At the end of the work, the developed controller is compared with a Fuzzy controller implemented in a mathematical program that it has a proper tool for the development and implementation of Fuzzy controllers, obtaining comparatives graphics of performance between both

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Induction motors are one of the most important equipment of modern industry. However, in many situations, are subject to inadequate conditions as high temperatures and pressures, load variations and constant vibrations, for example. Such conditions, leaving them more susceptible to failures, either external or internal in nature, unwanted in the industrial process. In this context, predictive maintenance plays an important role, where the detection and diagnosis of faults in a timely manner enables the increase of time of the engine and the possibiity of reducing costs, caused mainly by stopping the production and corrective maintenance the motor itself. In this juncture, this work proposes the design of a system that is able to detect and diagnose faults in induction motors, from the collection of electrical line voltage and current, and also the measurement of engine speed. This information will use as input to a fuzzy inference system based on rules that find and classify a failure from the variation of thess quantities

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Formalization of logical systems in natural deduction brings many metatheoretical advantages, which Normalization proof is always highlighted. Modal logic systems, until very recently, were not routinely formalized in natural deduction, though some formulations and Normalization proofs are known. This work is a presentation of some important known systems of modal logic in natural deduction, and some Normalization procedures for them, but it is also and mainly a presentation of a hierarchy of modal logic systems in natural deduction, from K until S5, together with an outline of a Normalization proof for the system K, which is a model for Normalization in other systems

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This paper describes a novel approach for mapping lightning processes using fuzzy logic. The estimation process is carried out using a fuzzy system based on Sugeno's architecture. Simulation results confirm that proposed approach can be efficiently used in these types of problem.

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From the geotechnical standpoint, it is interesting to analyse the soil texture in regions with rough terrain due to its relation with the infiltration and runoff processes and, consequently, the effect on erosion processes. The purpose of this paper is to present a methodology that provides the soil texture spatialization by using Fuzzy logic and Geostatistic. The results were correlated with maps drawn specifically for the study area. The knowledge of the spatialization of soil properties, such as the texture, can be an important tool for land use planning in order to reduce the potential soil losses during rain seasons. (c) 2011 Published by Elsevier Ltd. Selection and peer-review under responsibility of Spatial Statistics 2011

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Abortion is a very controversial and stigmatized subject, target of many criticism and discussions, mainly regarding to the legal, bioethical and religious aspects involved. In Brazil, abortion is considered a serious public health problem, being the major cause of maternal death due to its criminalization. The woman who causes an abortion is not up looked by society, since motherhood, culturally and historically, was imposed as a destination. Our main goal is to understand, from the existential-phenomenological perspective, the unique experience of the woman who induced the abortion This study is an offshoot of a larger study from USP in partnership with UFRN. Our participants were women who checked in on a maternity hospital in Natal with a miscarriage diagnosis and, among them, those who reported having induced abortion. Altogether, five women were interviewed. The used method was a phenomenological hermeneutics. The research revealed that the experience of abortion is a possibility that permeates women s life, being understood as a choice. This choice pervaded by much suffering, once it goes against everything that women are culturally taught and meant to be. The feeling more surfacing in this experiment, confirming the literature review, was blame. Abortion was also shown as an experience of helplessness and loneliness, due to lack of support from family and the partner. It was also revealed that abortion was made, mainly, by the desire of going along with future projects, including the prosecute of motherhood in the therms of what they consider ideal to a son s arrival, meaning, a family formation grounded on a stable relationship. Regarding the care provided by health professionals to these women, there is the need of restructuring the operating logic of SUS, so that women have the right to health in a integrate manner. This experience also made women reconsider the meanings they had towards abortion, and their life projects

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This study aimed to analyze some indicators of the restructuring process of place identity of natives resident in Tibau do Sul, a coastal town in the state of Rio Grande do Norte state, in relation to changes occurring in this locale in the last few decades. The concept of place identity a complex psychological structure in constant process of restructuring stresses the focus of this analysis on the aspects referring to the relationships of people with their physical and social environment throughout the transition process from the former village of fishermen and peasant farmers to the current growing town. Interviews with insider informants on local history were carried out as a preliminary step to getting in touch with the native participants. In total, 29 native local residents were interviewed, according to a wide range of personal and professional roles, focusing on their cognitions in regard to their past and present relationships with this context, as well as those related to expectancy for the future. The analysis focused both on the elements of distinctiveness, continuity, self-esteem and self-efficacy, and on how each of them have been valued (positive or negative). The participants evaluations of themselves and of the locale, as well as their distinctions in relation to others (people and places) were, in general, very positive. Many elements of group and place continuity, and the possibility of the satisfaction of their needs were highlighted positively, especially comparing to similar situations in the past. The development of the town, related to tourism as well as to other former economic activities, seemed to contribute to the restructuring process of place identity in a way of achieving desirable states for its structure. The broadening of the analysis to consider a wider spatial and temporal context, however, shows that such positive evaluation can be said to hinder some coping strategies of local residents faced with unsustainable economic activities, oftentimes handled to favor a minority of the population

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This paper discusses the expression of informality in contemporary capitalism. Thematic of relevance to the analysis of the reality of work today and the logic that moves the capital, its real presence in the lives of individuals. The street trading of Pau dos Ferros town, popularly known as "street market" was chosen as the search space. The main objective is to seize and examine the articulations and logic, present in the configuration of the street trading of this city, located in the state of Rio Grande do Norte, explaining the functionality of informality for capitalist accumulation, but also for the reproduction of segments of the working class. Our analysis is based in the perspective of totality, trying to grasp the historical determinations of the phenomenon in focus. It includes the analysis of the mechanisms used by the capital to reproduce itself in the current historical context, which has been implicated in the composition of the labor markets of different countries and in various forms of exploitation to which workers in general are subject. It also means discussing the development of capitalism in Brazil, the logic that permeates its dependence, and especially the use of over-exploitation of labor, as a lever for internal accumulation. The course of investigation consisted of theoretical research to form the basis of theoretical and methodological analysis and to outline the context in which our research object is inserted, and field research conducted in two phases: systematic observation, which allowed to map traders features and the infrastructure of commerce, and the conduction of interviews with key informants. The material collected was scrutinized according to analytical scheme inspired by the content analysis. Among the main considerations developed from the research process we include: the street trading of Pau dos Ferros remains shrouded in the majority sale of agricultural products, this demonstrates the structural characteristics of the region. However, the supply of this product is no longer restricted to the excess of small local producers. The presence of the dealer changed the distribution of the product, streamlining it. In parallel, business practices are developed, practices in which traded goods (industrial) reflect the moment of capitalist restoration, a larger business network. The reflections also made it possible to show that street trading follows developing on the basis of informal work, which gains functionality to the system, as it is configured as a space commonly used to drain part of the production, of industries (clothing/shoes), especially if the distribution is considered as an essential element of the complex process that aims at capital appreciation. This activity has been functioning as a place of employment and income generation for the subjects who are away from formal employment, masking, this way, unemployment, moreover, they allow them to continue as consumers. Such expressions reflect the ability and the logic of capital to expand and aggregate into so many realities. It is underway today, the logic that has led many workers to join the project of domination of capital, by the illusory chance to become capitalists. The aim has been to turn the subject into a consumer and the worker an enterprising

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O método de combinação de Nelson-Oppen permite que vários procedimentos de decisão, cada um projetado para uma teoria específica, possam ser combinados para inferir sobre teorias mais abrangentes, através do princípio de propagação de igualdades. Provadores de teorema baseados neste modelo são beneficiados por sua característica modular e podem evoluir mais facilmente, incrementalmente. Difference logic é uma subteoria da aritmética linear. Ela é formada por constraints do tipo x − y ≤ c, onde x e y são variáveis e c é uma constante. Difference logic é muito comum em vários problemas, como circuitos digitais, agendamento, sistemas temporais, etc. e se apresenta predominante em vários outros casos. Difference logic ainda se caracteriza por ser modelada usando teoria dos grafos. Isto permite que vários algoritmos eficientes e conhecidos da teoria de grafos possam ser utilizados. Um procedimento de decisão para difference logic é capaz de induzir sobre milhares de constraints. Um procedimento de decisão para a teoria de difference logic tem como objetivo principal informar se um conjunto de constraints de difference logic é satisfatível (as variáveis podem assumir valores que tornam o conjunto consistente) ou não. Além disso, para funcionar em um modelo de combinação baseado em Nelson-Oppen, o procedimento de decisão precisa ter outras funcionalidades, como geração de igualdade de variáveis, prova de inconsistência, premissas, etc. Este trabalho apresenta um procedimento de decisão para a teoria de difference logic dentro de uma arquitetura baseada no método de combinação de Nelson-Oppen. O trabalho foi realizado integrando-se ao provador haRVey, de onde foi possível observar o seu funcionamento. Detalhes de implementação e testes experimentais são relatados

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Intendding to understand how the human mind operates, some philosophers and psycologists began to study about rationality. Theories were built from those studies and nowadays that interest have been extended to many other areas such as computing engineering and computing science, but with a minimal distinction at its goal: to understand the mind operational proccess and apply it on agents modelling to become possible the implementation (of softwares or hardwares) with the agent-oriented paradigm where agents are able to deliberate their own plans of actions. In computing science, the sub-area of multiagents systems has progressed using several works concerning artificial intelligence, computational logic, distributed systems, games theory and even philosophy and psycology. This present work hopes to show how it can be get a logical formalisation extention of a rational agents architecture model called BDI (based in a philosophic Bratman s Theory) in which agents are capable to deliberate actions from its beliefs, desires and intentions. The formalisation of this model is called BDI logic and it is a modal logic (in general it is a branching time logic) with three access relations: B, D and I. And here, it will show two possible extentions that tranform BDI logic in a modal-fuzzy logic where the formulae and the access relations can be evaluated by values from the interval [0,1]

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Using the functional integral formalism for the statistical generating functional in the statistical (finite temperature) quantum field theory, we prove the equivalence of many-photon Greens functions in the Duffin-Kennner-Petiau and Klein-Gordon-Fock statistical quantum field theories. As an illustration, we calculate the one-loop polarization operators in both theories and demonstrate their coincidence.

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We consider a four-parameter family of point interactions in one dimension. This family is a generalization of the usual delta-function potential. We examine a system consisting of many particles of equal masses that are interacting pairwise through such a generalized point interaction. We follow McGuire who obtained exact solutions for the system when the interaction is the delta-function potential. We find exact bound states with the four-parameter family. For the scattering problem, however, we have not been so successful. This is because, as we point out, the condition of no diffraction that is crucial in McGuire's method is nor satisfied except when the four-parameter family is essentially reduced to the delta-function potential.

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Many-body systems of composite hadrons are characterized by processes that involve the simultaneous presence of hadrons and their constituents. We briefly review several methods that have been devised to study such systems and present a novel method that is based on the ideas of mapping between physical and ideal Fock spaces. The method, known as the Fock-Tani representation, was invented years ago in the context of atomic physics problems and was recently extended to hadronic physics. Starting with the Fock-space representation of single-hadron states, a change of representation is implemented by a unitary transformation such that composites are redescribed by elementary Bose and Fermi field operators in an extended Fock space. When the unitary transformation is applied to the microscopic quark Hamiltonian, effective, Hermitian Hamiltonians with a clear physical interpretation are obtained. The use of the method in connection with the linked-cluster formalism to describe short-range correlations and quark deconfinement effects in nuclear matter is discussed. As an application of the method, an effective nucleon-nucleon interaction is derived from a constituent quark model and used to obtain the equation of state of nuclear matter in the Hartree-Fock approximation.

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Os cromossomos e a variação de conteúdo de DNA nuclear foram estudados em sete amostras de Synbranchus marmoratus das bacias dos rios Paraguai e Paraná com o objetivo de avaliar se diferenças no cariótipo e no conteúdo de DNA nuclear poderiam fornecer informações para a caracterização de linhagens evolutivas independentes no gênero e para a elaboração de hipóteses evolutivas e biogeográficas. A ocorrência de diferentes cariótipos já foi descrita para essa espécie, entretanto, um novo citótipo foi encontrado no rio Miranda. O conteúdo de DNA nuclear mostrou uma ampla variação entre as amostras e indivíduos, com valores entre 5,2 a 9,1 pg de DNA/núcleo. Uma análise de variância confirmou a ocorrência de diferenças significativas entre as amostras. em uma série de análises, um padrão multimodal foi encontrado na distribuição do conteúdo de DNA nuclear, pelo qual várias unidades, mais ou menos discretas, foram identificadas. Combinando a fórmula cariotípica com o conteúdo de DNA nuclear, uma relação complexa entre os rios foi observada. Com base nos dados disponíveis, sugerimos que existem várias linhagens evolutivas independentes de Synbranchus marmoratus nos rios amostrados. Hipóteses biogeográficas são propostas e discutidas.