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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

The use of a body-wide automatic anatomy recognition system in image analysis of kidneys

Mohammadianrasanani, Seyedmehrdad January 2013 (has links)
No description available.
232

The use of a body-wide automatic anatomy recognition system in image analysis of kidneys

Mohammadianrasanani, Seyedmehrdad January 2013 (has links)
No description available.
233

Mathematical modelling in classroom: The importance of validation of the constructed model

Voskoglou, Michael Gr. 20 March 2012 (has links)
No description available.
234

Možnosti řízení a minimalizace rizik technologie výroby stavebních materiálů a výrobků pomocí fuzzy logiky a dalších nástrojů risk managementu / Management options and risk minimizing of production technologies of building materials and products by using fuzzy logic and other risk management tools

Misák, Petr January 2014 (has links)
The thesis proposes management options and risk minimizing in the field of building materials production technologies and related products using fuzzy logic and other risk management tools. The thesis indicates why some methodologies are not commonly used. The main purpose of this work (thesis) is to propose possible upgrades of standard methods in process capability and risk minimizing related to building materials and products. Markov analysis and fuzzy Markov chains are applied.
235

De l'approche monétaire à l'approche par les capabilités : une analyse multidimensionnelle de la pauvreté au Sénégal sur les données de l'Enquête de Suivi de la Pauvreté au Sénégal (ESPS2) / From the monetary approach to the capability approach : a multidimensional analysis of poverty in Senegal on data from the Survey of Poverty Monitoring in Senegal (ESPS2)

Diop, Mayoro 27 November 2014 (has links)
L'objectif de cette thèse est de proposer une analyse multidimensionnelle de la pauvreté au Sénégal, et de montrer l'intérêt d'intégrer l'approche par les capabilités dans l'analyse de la pauvreté. Cette thèse vise à faire valoir que l'approche par les capabilités est un cadre adéquat et pertinent pour l'identification des pauvres et présente un grand intérêt pour l'élaboration de meilleures politiques publiques de lutte contre la pauvreté en rapport avec les OMD.Pour mener à bien ce travail, la thèse s'organise en deux temps. Dans un premier, il est question de traiter du concept de pauvreté en confrontant l'approche monétaire traditionnelle et l'approche par les capabilités, et de montrer l'intérêt de l'économie du bonheur dans l'analyse de la pauvreté et du bien-être. Dans un second temps, il s'agit d'éclairer les options méthodologiques pour traiter empiriquement la mesure de la pauvreté et d'apporter les arguments en faveur de l'approche par les capabilités.Les traits essentiels de cette thèse s'organisent autour de trois apports principaux. Le premier est d'ordre théorique. Il propose une analyse de la pauvreté au Sénégal en termes de capabilités. Le second est d'ordre empirique et fournit une mesure multidimensionnelle basée sur la théorie des ensembles flous à partir de l'enquête de suivi de la pauvreté au Sénégal (ESPS 2). Le troisième est méthodologique et propose une démarche originale qui consiste à construire un noyau dur de la pauvreté utilitariste (en confrontant les pauvretés monétaire et subjective), puis d'analyser l'évolution de ce noyau dur selon la distribution des degrés de pauvreté des capabilités. / The aim of this thesis is to propose a multidimensional analysis of poverty in Senegal, and to show the importance of integrating the capability approach in the analysis of poverty. This thesis aims at showing that the capability approach is an adequate and appropriate framework for identifying the poor and proves to be of real interest in setting up better public policies in order to fight against poverty relating to the MDGs.This study is divided in two parts. The first part deals with the concept of poverty confronting the traditional monetary approach with the capability approach, and shows the interest of the economics of happiness in the analysis of poverty and well being. In a second phase, the objective is to illuminate methodological options in order to treat the extent of poverty empirically and bring the arguments in favor of the capability approach.The essential features of this thesis revolve around three main contributions. The first one is theoretical. It offers an analysis of poverty in Senegal in terms of capabilities. The second is empirical and provides a multidimensional measure based on the theory of fuzzy sets from the monitoring survey of poverty in Senegal (MSPS 2). The third one is methodological and proposes an original approach consisting of building a core of utilitarian poverty (by comparing the monetary and subjective poverty) and then analyzing the evolution of the core according to the distribution of the degrees of poverty capabilities.
236

Gráficos de controle fuzzy para o monitoramento da média e amplitude de processos univariados /

Mendes, Amanda dos Santos January 2019 (has links)
Orientador: Marcela Aparecida Guerreiro Machado Freitas / Resumo: O controle de qualidade, principalmente por meio do uso de gráficos de controle, torna-se essencial na indústria para garantir um processo livre de causas especiais de variabilidade. Como os dados amostrais podem incluir incertezas advindas da subjetividade humana e dos sistemas de medição, a teoria dos conjuntos fuzzy pode ser aplicada aos gráficos de controle quando dados precisos não estiverem disponíveis. Para tal feito, os valores da característica de qualidade são fuzzificados a partir da inserção de incertezas e transformados em valores representativos para uma melhor comparação com o gráfico de controle tradicional. Este trabalho propõe o uso da lógica fuzzy aos gráficos de controle para monitorar a média e a amplitude de processos univariados, assim como dois gráficos de controle fuzzy baseados nas regras especiais de decisão: Synthetic e Side Sensitive Synthetic. O desempenho do gráfico de controle é medido pelo número médio de amostras até sinal (NMA). Verificou-se neste trabalho que os gráficos de controle fuzzy possuem maior eficiência que os gráficos de controle tradicionais para menores valores de α-cut, ou seja, maior incerteza inserida no processo e para cenários onde se tem uma maior diferença entre os limitantes de incerteza dos números fuzzy. / Abstract: Quality control, mainly through the use of control charts, becomes essential in the industry to ensure a process free from special causes of variability. As sample data may include uncertainties arising from human subjectivity and measurement systems, fuzzy set theory can be applied to control charts when accurate data is not available. For this purpose, the quality characteristic values are fuzzified from the insertion of uncertainties and transformed into representative values for a better comparison with the traditional control chart. This work proposes the use of fuzzy logic to control charts to monitor the mean and range of univariate processes, as well as two fuzzy control charts based on the special run rules: Synthetic and Side Sensitive Syntehtic. The performance of the control chart is measured by the average run length (ARL). It was verified in this work that the fuzzy control charts have higher efficiency than the traditional control charts for lower values of α-cut, that is, greater uncertainty inserted in the process and for scenarios where there is a greater difference between the limiting uncertainties of fuzzy numbers. / Mestre
237

Modelo multiobjetivo Fuzzy de análise envoltória de dados na avaliação da eficiência de máquinas industriais em um contexto sob incerteza /

Guimarães, Erica Peixoto January 2019 (has links)
Orientador: Aneirson Francisco da Silva / Resumo: A gestão baseada no Lean Manufacturing tem como princípio o desenvolvimento de processos enxutos com a capacidade de utilizar da melhor forma os recursos disponíveis e eliminar atividades que não agregam valor. Com isso, o programa Total Productive Maintenance (TPM), está entre os métodos que auxiliam nesse objetivo, pois desenvolve a função de gerir a manutenção de máquinas, equipamentos e meio ambiente de trabalho de forma que os investimentos feitos tendam ao aumento da eficiência global. Para isso, uma maneira de controlar o desempenho dos processos é aplicando ferramentas capazes de mensurar a eficiência relativa. Pois, além de verificar quantitativamente a eficiência relativa, estes métodos e ferramentas servem de fundamentação para auxiliar os gestores na tomada de decisões nas organizações. A empresa em estudo, uma multinacional de autopeças situada no Vale do Paraíba/SP, emprega o programa TPM e apoia-se no indicador Overall Equipment Effectiveness (OEE) para as avaliações de eficiência. Entretanto, o presente estudo propôs um indicador de eficiência que combina um modelo multicritério com a Lógica dos Conjuntos Fuzzy, no qual, diferentemente do OEE, é possível escolher os parâmetros que interferem na eficiência do processo e adicionar o conhecimento dos especialistas aos dados nítidos para assim, verificar o comportamento do cenário. Para o indicador proposto, foram simulados três cenários, dispostos em forma de ranking (do mais eficiente ao menos eficiente) e compa... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Management based on Lean Manufacturing has as principle the development of lean processes with the ability to make the best use of available resources and eliminate activities that do not add value. Thus, the Total Productive Maintenance (TPM) program is one of the methods that help this goal, because it develops the role of managing the maintenance of machinery, equipment and working environment, for that the investments made tend to increase the overall efficiency. For this, one way to control process performance is to apply tools developed to measure relative efficiency. Because, in addition to quantitatively verifying relative efficiency, these methods and tools are based managers for decision-making in organizations. The company under study, an auto parts multinational located in Vale do Paraíba / SP, use the TPM program and for efficiency assessments is supported by the Overall Equipment Effectiveness (OEE) indicator. However, the present study proposed an efficiency indicator that combines a multicriteria model with the Fuzzy Set Logic, in which, unlike OEE, it is possible to choose the parameters that interfere in the process efficiency and to add expert knowledge to the clear data for verify the behavior of the scenario. For the proposed indicator, three scenarios were simulated, creating the ranking (from the most efficient to the least efficient) and compared to the OEE indicator ranking. Once this was done, it was observed that there was divergence in most positio... (Complete abstract click electronic access below) / Mestre
238

Uncertainty Modelling And Stability Analysis For 2-way Fuzzy Adaptive Systems

Gurkan, Evren 01 January 2003 (has links) (PDF)
A novel fuzzy system named as 2-way fuzzy system is developed by combining the intuitionistic fuzzy set theory with the fuzzy systems theory. The developed system is used in modelling and minimizing uncertainty and inconsistency. Uncertainty is the width of the interval introduced by the independent assignment of membership and nonmembership functions of the intuitionistic fuzzy sets / and inconsistency is the violation of the consistency inequality in this assignment. The uncertainty and inconsistency is reduced through a 2 phase training. An evaluation of the degree of reduction of inconsistency is carried out at the end of the rst phase of training by forming the shadowed set patterns of the membership and nonmembership functions. The system is further trained for a second phase in order to reduce uncertainty. There are three dierent methods developed for the stability analysis of fuzzy systems. The rst method is based on the approximating sequences technique, and the design turns into an optimal control problem. In the sec ond analysis, describing function of a 2-way fuzzy system is evaluated analytically, and a systematic design approach is developed using describing function technique. The last analysis technique employs the Lie algebra theory in the stability analysis of Takagi-Sugeno fuzzy systems. The theoretical results are simulated on an application system, which is a exible-joint robot arm system.
239

Estudi de mètodes de classificació borrosa i la seva aplicació a l'agrupació de zones geogràfiques en base a diverses característiques incertes

Clara i Lloret, Narcís 22 July 2004 (has links)
Aquesta memòria està estructurada en sis capítols amb l'objectiu final de fonamentar i desenvolupar les eines matemàtiques necessàries per a la classificació de conjunts de subconjuntsborrosos. El nucli teòric del treball el formen els capítols 3, 4 i 5; els dos primers són dos capítols de caire més general, i l'últim és una aplicació dels anteriors a la classificació delspaïsos de la Unió Europea en funció de determinades característiques borroses.En el capítol 1 s'analitzen les diferents connectives borroses posant una especial atenció en aquells aspectes que en altres capítols tindran una aplicació específica. És per aquest motiu que s'estudien les ordenacions de famílies de t-normes, donada la seva importància en la transitivitat de les relacions borroses. Laverificació del principi del terç exclòs és necessària per assegurar que un conjunt significatiu de mesures borroses generalitzades, introduïdes en el capítol 3, siguin reflexives.Estudiem per a quines t-normes es verifica aquesta propietat i introduïm un nou conjunt de t-normes que verifiquen aquest principi.En el capítol 2 es fa un recorregut general per les relacions borroses centrant-nos en l'estudi de la clausura transitiva per a qualsevol t-norma, el càlcul de la qual és en molts casosfonamental per portar a terme el procés de classificació. Al final del capítol s'exposa un procediment pràctic per al càlcul d'unarelació borrosa amb l'ajuda d'experts i de sèries estadístiques.El capítol 3 és un monogràfic sobre mesures borroses. El primer objectiu és relacionar les mesures (o distàncies) usualment utilitzades en les aplicacions borroses amb les mesuresconjuntistes crisp. Es tracta d'un enfocament diferent del tradicional enfocament geomètric. El principal resultat és la introducció d'una família parametritzada de mesures que verifiquenunes propietats de caràcter conjuntista prou satisfactòries.L'estudi de la verificació del principi del terç exclòs té aquí la seva aplicació sobre la reflexivitat d'aquestes mesures, que sónestudiades amb una certa profunditat en alguns casos particulars.El capítol 4 és, d'entrada, un repàs dels principals resultats i mètodes borrosos per a la classificació dels elements d'un mateixconjunt de subconjunts borrosos. És aquí on s'apliquen els resultats sobre les ordenacions de les famílies de t-normes i t-conormes estudiades en el capítol 1. S'introdueix un nou mètodede clusterització, canviant la matriu de la relació borrosa cada vegada que s'obté un nou clúster. Aquest mètode permet homogeneïtzar la metodologia del càlcul de la relació borrosa ambel mètode de clusterització.El capítol 5 tracta sobre l'agrupació d'objectes de diferent naturalesa; és a dir, subconjunts borrosos que pertanyen a diferents conjunts. Aquesta teoria ja ha estat desenvolupada en elcas binari; aquí, el que es presenta és la seva generalització al cas n-ari. Més endavant s'estudien certs aspectes de les projeccions de la relació sobre un cert espai i el recíproc,l'estudi de cilindres de relacions predeterminades. Una aplicació sobre l'agrupació de les comarques gironines en funció de certesvariables borroses es presenta al final del capítol.L'últim capítol és eminentment pràctic, ja que s'aplica allò estudiat principalment en els capítols 3 i 4 a la classificació dels països de la Unió Europea en funció de determinadescaracterístiques borroses. Per tal de fer previsions per a anys venidors s'han utilitzat sèries temporals i xarxes neuronals.S'han emprat diverses mesures i mètodes de clusterització per tal de poder comparar els diversos dendogrames que resulten del procésde clusterització.Finalment, als annexos es poden consultar les sèries estadístiques utilitzades, la seva extrapolació, els càlculs per a la construcció de les matrius de les relacions borroses, les matriusde mesura i les seves clausures. / This thesis is organized in six chapters with the final goal to found and explain the mathematical set of tools necessary to classify sets of fuzzy sets. The theoretic kernel is made by the chapters 3, 4 and 5; the first and second are more generals and the last one is an aplication of the precedent to make a classification of the union european countries in function of some vague attibutes.In the first chapter we analize the different fuzzy logic connectives making a special attention those aspects which will have a specific application in other chapters. Is for this reason that we study the order of families of t-norms, given its importance in the transivity of fuzzy relations. The verification of the third excluded principle is necessary to ensure that a significant set of generalized fuzzy measures, introduced in the chapter 3, were reflexive. We study for which t-norms is verified this property and we introduce a new set of t-norms which verify this principle.In the second chapter we study in a general way the fuzzy relations making a special attention in the transivity closure for any t-norm, its calculus is in a lot of cases basic to make the classification process. At the end of this chapter we describe a practical method to find a fuzzy relation with the help of experts and statistical series.The third chapter is a monographic about fuzzy measures. The first goal is to relate the measures (or distances) usually used in the fuzzy applications with the crisp measures. The question is to change the traditional geometrical point of view for another absolutely fuzzy. The first result is the introduction of a parametrized family of measures that verify a set of properties enough satisfactories. The study of the third exclude principle has here its application about the reflexivity of these measures which are studied with certain profundity in some particular cases.The fourth chapter is, at the beginning, a review of the main results and fuzzy methods for the classification of elements of a same set of fuzzy sets. Is now where we apply the results of orders for t-norms and t-conorms studied in the first chapter. We introduce a new method of fuzzy clustering, changing the fuzzy relation matrix each time that we obtain a new cluster. This method permit to homogenize the methodology of the calculus of the fuzzy relation with the clustering method.The fifth chapter is about the objects association of different nature; that is, fuzzy subsets that belong to different sets. This theory already has been developed in the binary case; here, we submit its generalization for the n dimensional case. Later, we study certain aspects of the fuzzy relation projection on a certain space and the reciprocal, the cilindrical extensions. An application about grouping regions of Girona in function of some uncertain attibutes finish the chapter.The last chapter is eminently applied, because we apply that studied in the 3 and 4 chapters to classify the union european countries in function of some fuzzy attributes. To do forecasts for coming years we have used time series and neural networks. We have used several measures and clustering methods in order to compare the dendograms that result of the clustering process.Finally, in the suplements we can consult the used time series, its extrapolation, the calculus to construct the fuzzy relations, the measure matrixs and its closures.
240

Problemas de controle ótimo intervalar e intervalar fuzzy /

Campos, José Renato January 2018 (has links)
Orientador: Edvaldo Assunção / Resumo: Neste trabalho estudamos problemas de controle ótimo intervalar e intervalar fuzzy. Em particular, propomos problemas de controle ótimo via teoria de incerteza generalizada e teoria dos conjuntos fuzzy. Dentre os vários tipos de incerteza generalizada utilizamos apenas a intervalar. Embora as abordagens do processo de solução dos problemas de controle ótimo intervalar e intervalar fuzzy sejam similares, as premissas iniciais para o uso e identificação de aplicação delas em problemas práticos são distintas assim como é distinto o processo de tomada de decisão. Assim, propomos inicialmente o problema de controle ótimo intervalar em tempo discreto. A primeira proposta de solução para o problema de controle ótimo intervalar em tempo discreto é construída usando a aritmética intervalar restrita de níveis simples juntamente com a técnica de programação dinâmica. As respostas do problema de controle ótimo intervalar contêm as possibilidades de soluções viáveis, e para implementar uma solução viável para o usuário final usamos a solução que minimiza o arrependimento máximo nos exemplos numéricos. A segunda proposta de solução para o problema de controle ótimo intervalar em tempo discreto é realizada com a aritmética intervalar restrita uma vez que essa aritmética intervalar é mais geral do que a aritmética intervalar restrita de níveis simples pois não considera os intervalos envolvidos nas operações variando de forma dependente. Exemplos numéricos também foram construídos e ilustram... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work we study the interval optimal control problem and fuzzy interval optimal control problem. In particular, we propose optimal control problems via theory of generalized uncertainty and fuzzy set theory. Among the various types of generalized uncertainty we use only the interval uncertainty. Although the approaches to solve the interval optimal control problem and fuzzy interval optimal control problem are similar, the input data for problems with generalized uncertainty and flexibility are distinct as is distinct the decision-making process. Thus, we initially propose the discrete-time interval optimal control problem. The first solution method to solve the discrete-time interval optimal control problem is constructed using single-level constrained interval arithmetic coupled with a dynamic programming technique. The optimal interval solution contains the real-valued optimal solutions, and to implement a feasible solution to the user we use the minimax regret criterion in numerical examples. The second solution method to solve the discrete-time interval optimal control problem is done with the constrained interval arithmetic since this interval arithmetic is more general than the single-level constrained interval arithmetic because it does not have its intervals varying of dependent form in interval operations. Numerical examples have also been constructed and illustrate the method of solution. Finally, we study the discrete-time fuzzy interval optimal control prob... (Complete abstract click electronic access below) / Doutor

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