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Moderní trendy v oboru počítačová fyzika / Modern trends in the area of computer physicsSURYNEK, Radek January 2013 (has links)
The theme of the thesis is to make a list few fundamental modern methods which can be used in computerized physics. The thesis describes parallel computing, neural networks,genetic algorithms, fuzzy logic. Every chapter include theoretical description, simplified mathematical expression, proposals of technical solution. Applications are briefly mentioned here too. The printed matter is completed with a few simple examples. The closing part of the thesis acquired information about these methods and outlines their future development.
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Pobreza multidimensional na regi?o nordeste: uma aplica??o da Teoria dos Conjuntos Fuzzy (em 2010)Ottonelli, Jana?na 03 June 2013 (has links)
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Previous issue date: 2013-06-03 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Pobreza significa priva??o. A priva??o sofrida pelas pessoas pobres normalmente est?
relacionada ao baixo n?vel de renda. Quando se trata da pobreza no Brasil, a Regi?o Nordeste
se destaca, pois em 2010 o Plano Brasil Sem Mis?ria apontou a exist?ncia de 9,6 milh?es de
extremamente pobres na regi?o, representando 59% do total no pa?s (BRASIL, 2011b). No
entanto, a renda monet?ria n?o captura completamente as priva??es sofridas pelas pessoas. O
conceito de pobreza tem passado por uma evolu??o no sentido de incluir dimens?es
importantes sobre a vida das pessoas. Deixou de focar apenas a priva??o absoluta da
abordagem unidimensional e passou a considerar a priva??o relativa, uma abordagem
multidimensional. Este estudo fundamenta-se na Abordagem das Capacita??es de Sen (1981,
1985, 2000, 2001) que considera a pobreza como a priva??o sofrida pelas pessoas relacionada
a diferentes aspectos tais como nutri??o, acesso aos servi?os b?sicos de educa??o, sa?de,
saneamento b?sico e, tamb?m, de liberdade. Assim, o objetivo deste estudo ? investigar e
mensurar a intensidade da pobreza multidimensional nos munic?pios da Regi?o Nordeste
atrav?s do Censo Demogr?fico (IBGE, 2010). Para isso, utilizou-se da t?cnica da Teoria dos
Conjuntos Fuzzy que permite o c?lculo de ?ndice relativo. A mensura??o da pobreza por meio
do ?ndice fuzzy de pobreza (IFP) envolveu a escolha de 19 indicadores distribu?dos em quatro
dimens?es (ou capacita??es): educa??o, sa?de, condi??es habitacionais e renda. Os resultados
mostraram que existe maior pobreza na dimens?o renda. Entretanto, as dimens?es educa??o e
sa?de tamb?m tiveram import?ncia no indicador de pobreza multidimensional. Alguns
indicadores que merecem aten??o dos formuladores de pol?ticas p?blicas s?o o acesso ao
ensino fundamental e ensino m?dio e o acesso aos servi?os de saneamento b?sico, coleta de
lixo e rede de ?gua. Apesar da priva??o na dimens?o renda ser maior do que nas demais
dimens?es, a supera??o da pobreza envolve a promo??o dos diferentes aspectos relacionados
? vida das pessoas. A Abordagem da Capacita??o mostra que pol?ticas de assist?ncia aos
pobres precisam considerar as particularidades do local e h?bitos, de forma a verificar quais
s?o as reais priva??es sofridas pelas pessoas. As pessoas que se encontram em situa??o de
pobreza precisam ser incentivadas a superar a situa??o de mis?ria e pen?ria de forma a n?o
serem eternamente privadas de liberdade e privadas de expandirem suas capacita??es
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Sistemática para seleção de fornecedores na indústria da construção civilDenicol, Juliano January 2014 (has links)
Atualmente, o ambiente industrial é caracterizado pela intensa globalização, competição entre cadeias de suprimentos, manutenção das competências centrais e terceirização dos demais serviços. Desta forma, a gestão das relações entre os agentes independentes da cadeia de suprimentos e do processo de aquisição são fatores potenciais para o aumento da competitividade empresarial. No contexto da construção civil, a seleção adequada dos parceiros de negócios é um elemento fundamental para o sucesso dos projetos, uma vez que uma grande proporção das atividades podem ser sub-contratadas e possuem relação de precedência entre si. Os suprimentos representam um percentual significativo dos custos das construções, 60%, dado que demonstra o potencial de lucratividade passível de ser atingida ao estruturar o processo de seleção de fornecedores na construção civil. Seleções baseadas no preço prejudicam os sub-empreiteiros e fornecedores mais responsáveis na concorrência, contribuindo para a queda do nível de desempenho e redução da eficiência global do projeto, uma vez que as ineficiências são somadas ao longo da cadeia. Através da estruturação do processo de seleção de fornecedores, é possível mitigar os riscos de suprimentos oriundos de falhas destes contratados ao longo da relação. O objetivo deste trabalho foi desenvolver uma sistemática para seleção de fornecedores críticos, considerando diversos critérios além do preço, entre qualitativos e quantitativos. A abordagem visa também, a eliminação da subjetividade do processo e a extração do melhor fornecedor de forma objetiva. Para tanto, foram definidas dimensões competitivas para avaliar os fornecedores e posteriormente foram utilizados dois métodos quantitativos, Teoria dos Conjuntos Difusos (TCD) e Análise de Componentes Principais (ACP), para selecionar o melhor fornecedor dentre as alternativas, com base na avaliação de múltiplos agentes. / Currently, the industrial environment is characterized by intense globalization, competition between supply chains, maintenance of core competencies and outsourcing of other services. Thus, the management of relationships between independent agents of the supply chain and the procurement process are potential factors for increasing enterprise competitiveness. In the construction context, the proper selection of business partners is a key element for the success of projects, since a large proportion of the activities can be sub-contracted and have precedence relationship between them. Supplies represent a significant percentage of the cost of buildings, 60%, information that demonstrates the potential of profitability that can be achieved by structuring the process of supplier selection in the construction industry. Selection based on price take off from competition the sub-contractors and suppliers more responsible, contributing to the decline in the level of performance and reduction in the overall project efficiency, since inefficiencies are summed through the chain. By structuring the supplier selection process, it is possible to mitigate the supply risk arising from failures of these suppliers during the relationship. The objective of this study was to develop a systematic for selection of critical suppliers, considering several criteria other than price, among qualitative and quantitative. The approach also aims at eliminating the subjectivity of the process and the extraction of the best supplier in an objective way. In order to that, competitive dimensions were set to evaluate vendors and subsequently two quantitative methods, Fuzzy Sets Theory (FST) and Principal Component Analysis (PCA) were used to select the best supplier among the alternatives based on multiple agents evaluation.
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Viabilidade de projetos de investimento em equipamentos com tecnologia avançada de manufatura: estudo de múltiplos casos na siderurgia brasileira. / Investment projects feasibility in equipment with advanced manufaturing technology: multiple cases study in the Brazilian siderurgy.Carlos Shinoda 26 March 2008 (has links)
Esta tese busca, de início, pesquisar comparativamente, com a abrangência possível, os métodos e processos pelos quais as empresas componentes do setor siderúrgico nacional avaliam - sob o ponto de vista da viabililidade - a tomada de suas decisões relativamente a seus peculiares e vultosos investimentos em equipamentos de tecnologia avançada de manufatura. Revisita primária e metodologicamente amplo repertório de métodos de avaliação consagrados pela prática e pela literatura, tendo como cenário o setor em referência representado pelas várias modalidades industriais que o suportam. A pesquisa é realizada com base no estudo de múltiplos casos realizados em grandes empresas siderúrgicas, a partir de visitas a suas instalações e entrevistas com seus especialistas de análise de viabilidade de projetos de investimento. Ao final, oferece modelo de avaliação a ser adotado complementarmente aos critérios utilizados pelo setor em referência, a partir das observações e discussões efetuadas em campo. / This thesis initially seeks to search, in a comparative basis and with the permissible largeness, the methods and procedures through which the companies comprising the national siderurgic sector appraise their decisions referring to their peculiar and huge investments in AMT equipments, under a feasibility point of view. A primary review is made, in a comparative way, of a large well known evaluation methods repertoire, in a background at which act the various concerned industrial modalities. The search is accomplished based on the study of multiple cases realized at big siderurgic companies, by visiting their installations and by interviewing their specialists in investment feasibility project analysis. Eventually offers an evaluation model to be adopted by this sector, based upon the observation and discussions made in the related field research.
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Analysis of Quality of Experience by applying Fuzzy logic : A study on response timeAtaeian, Seyed Mohsen, Darbandi, Mehrnaz Jaberi January 2011 (has links)
To be successful in today's competitive market, service providers should look at user's satisfaction as a critical key. In order to gain a better understanding of customers' expectations, a proper evaluations which considers intrinsic characteristics of perceived quality of service is needed. Due to the subjective nature of quality, the vagueness of human judgment and the uncertainty about the degree of users' linguistic satisfaction, fuzziness is associated with quality of experience. Considering the capability of Fuzzy logic in dealing with imprecision and qualitative knowledge, it would be wise to apply it as a powerful mathematical tool for analyzing the quality of experience (QoE). This thesis proposes a fuzzy procedure to evaluate the quality of experience. In our proposed methodology, we provide a fuzzy relationship between QoE and Quality of Service (QoS) parameters. To identify this fuzzy relationship a new term called Fuzzi ed Opinion Score (FOS) representing a fuzzy quality scale is introduced. A fuzzy data mining method is applied to construct the required number of fuzzy sets. Then, the appropriate membership functions describing fuzzy sets are modeled and compared with each other. The proposed methodology will assist service providers for better decision-making and resource management.
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Sistemática para seleção de fornecedores na indústria da construção civilDenicol, Juliano January 2014 (has links)
Atualmente, o ambiente industrial é caracterizado pela intensa globalização, competição entre cadeias de suprimentos, manutenção das competências centrais e terceirização dos demais serviços. Desta forma, a gestão das relações entre os agentes independentes da cadeia de suprimentos e do processo de aquisição são fatores potenciais para o aumento da competitividade empresarial. No contexto da construção civil, a seleção adequada dos parceiros de negócios é um elemento fundamental para o sucesso dos projetos, uma vez que uma grande proporção das atividades podem ser sub-contratadas e possuem relação de precedência entre si. Os suprimentos representam um percentual significativo dos custos das construções, 60%, dado que demonstra o potencial de lucratividade passível de ser atingida ao estruturar o processo de seleção de fornecedores na construção civil. Seleções baseadas no preço prejudicam os sub-empreiteiros e fornecedores mais responsáveis na concorrência, contribuindo para a queda do nível de desempenho e redução da eficiência global do projeto, uma vez que as ineficiências são somadas ao longo da cadeia. Através da estruturação do processo de seleção de fornecedores, é possível mitigar os riscos de suprimentos oriundos de falhas destes contratados ao longo da relação. O objetivo deste trabalho foi desenvolver uma sistemática para seleção de fornecedores críticos, considerando diversos critérios além do preço, entre qualitativos e quantitativos. A abordagem visa também, a eliminação da subjetividade do processo e a extração do melhor fornecedor de forma objetiva. Para tanto, foram definidas dimensões competitivas para avaliar os fornecedores e posteriormente foram utilizados dois métodos quantitativos, Teoria dos Conjuntos Difusos (TCD) e Análise de Componentes Principais (ACP), para selecionar o melhor fornecedor dentre as alternativas, com base na avaliação de múltiplos agentes. / Currently, the industrial environment is characterized by intense globalization, competition between supply chains, maintenance of core competencies and outsourcing of other services. Thus, the management of relationships between independent agents of the supply chain and the procurement process are potential factors for increasing enterprise competitiveness. In the construction context, the proper selection of business partners is a key element for the success of projects, since a large proportion of the activities can be sub-contracted and have precedence relationship between them. Supplies represent a significant percentage of the cost of buildings, 60%, information that demonstrates the potential of profitability that can be achieved by structuring the process of supplier selection in the construction industry. Selection based on price take off from competition the sub-contractors and suppliers more responsible, contributing to the decline in the level of performance and reduction in the overall project efficiency, since inefficiencies are summed through the chain. By structuring the supplier selection process, it is possible to mitigate the supply risk arising from failures of these suppliers during the relationship. The objective of this study was to develop a systematic for selection of critical suppliers, considering several criteria other than price, among qualitative and quantitative. The approach also aims at eliminating the subjectivity of the process and the extraction of the best supplier in an objective way. In order to that, competitive dimensions were set to evaluate vendors and subsequently two quantitative methods, Fuzzy Sets Theory (FST) and Principal Component Analysis (PCA) were used to select the best supplier among the alternatives based on multiple agents evaluation.
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Risk Management Model for International Public Construction Joint Venture Projects in KuwaitBu-Qammaz, Amani S A S 21 May 2015 (has links)
No description available.
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Fuzzy Partial Credit Scaling: Applying Fuzzy Set Theory to Scoring Rating Scales游森期, Yu, Sen-Chi Unknown Date (has links)
本研究的目的在於結合部份計分模式(partial credit model, PCM)與模糊集合論(fuzzy set theory),提出評定量表的不同計分方式:模糊部份計分法(fuzzy partial credit scaling, FPCS)。FPCS是根據 PCM 所估計出的梯度參數(step parameters)來建構三角形模糊數,三角形模糊數代表選擇某個特定選項的受試者的能力分配情形。接著,利用中心法(center of gravity method) 將三角形模糊數解模糊化為純量。最後,利用隸屬度當作權重,計算個別受試者的模糊觀察分數,並且用模糊觀察分數當作量表的總分。
本研究採用貝克憂鬱量表(Beck Depression Inventory-II, BDI)中文版為研究工具。本研究的樣本分為憂鬱症病患與非憂鬱症的一般大學生兩大類。240位憂鬱症病患樣本是由台北市立和平醫院精神科門診募集而來;321位大學生則以便利抽樣的方式募集而來。
為了驗証FPCS的有效性,本研究進行三個子研究,來比較FPCS與傳統計分法在信度、效度、集群分析的分類正確性。
子研究一探討FPCS的信度。本研究以Cronbach alpha係數來衡量量表的內部一致性,並且以結構方程式模式(structure equation modeling)進行驗證性因素分析所估計的各試題的變異數被潛在構念解釋的比例當作信度的指標。由研究結果顯示,以量表整體而言,FPCS計分的結果得到較高的內部一致性;以各題而言,量表各試題的變異數被潛在構念解釋的百分比高於傳統的原始分數。此結果顯示FPCS的計分方式可以降低測量誤差,提升信度。
子研究二探討FPCS的效度,本研究以精神科醫師的診斷當作效標,分別以FPCS與原始分數兩種不同的計分法當作自變項,以預測效度當作效度的指標。首先,將是否罹患憂鬱症編碼為二元變數,不同計分法所得到的量表分數當作自變數,進行Logistic迴歸分析。研究結果顯示,相較於原始分數,FPCS預測罹患憂鬱症的正確率由 74.8% 提升到 77.2%。接下來,依照所有樣本的憂鬱程度,區分為一般樣本、憂鬱症且緩解、憂鬱症無緩解三類,進行區別分析。研究結果顯示,相較於原始分數,FPCS分類正確率由 71.2% 提升到 80.7%。上述的研究結果顯示,FPCS具有較高的效度,可以降低誤判憂鬱症的機率。
子研究三比較模糊集群分析(fuzzy c-means, FCM)與傳統明確邏輯的集群分析。首先利用分群效度(clustering validity)指標,決定群數為三群。並以此結果,指定模糊集群、Wald法、k-means法之群數。為了比較分類的效果,將模糊集群之樣本,指定給獲得最大隸屬度之集群。並且以醫師的診斷的憂鬱程度當作評估分類結果之標準。研究結果顯示,相較於傳統明確邏輯的集群分析(Wald法、k-means法),模糊集群分析得到分群結果,與醫師的診斷的結果有最高的相關。結果顯示模糊集群分析更能夠忠實的反映資料結構。
整體而言,相較於原始分數,FPCS有較高的信度、效度、分類正確性。此實証性研究結果支持了模糊集合論應用於心理學研究的可行性;多值的模糊邏輯比二值明確邏輯更能夠正確反映出人類的思維。 / The aim of this study was to propose and validate the new scaling method, fuzzy partial credit scaling (FPCS), which combines fuzzy set theory with the partial credit model (PCM) to score rating scales. To achieve this goal, the Chinese version of BDI (Beck Depression Inventory-II) was administrated to a depressed sample of patients and a non-depressed sample. The depressed sample consisted of 240 outpatients who were diagnosed as depressed by a psychiatric doctor, while 321 undergraduate students were recruited for the nondepressed sample.
In FPCS, triangular fuzzy numbers were generated by step parameters to characterize distributions of each alternative value. Next, the center of gravity (COG) method was applied to “de-fuzzify” the fuzzy number into a scalar. Then, the “observed fuzzy scores” defined in FPCS were calculated as the sums of fuzzy number values weighted by membership degrees for the following analysis.
Three studies were performed to compare the differences in reliability, validity and clustering precision between the raw score and FPCS.
In Study One, the reliability issue of FPCS was discussed. The results of confirmatory factor analysis demonstrate that the BDI reliability was higher in FCPS than in raw scoring. That is, compared with raw scoring, scoring via FPCS produced fewer measurement errors, meaning that more variances in an item of BDI were explained by depression.
In Study Two, the predictive validity issue of FPCS was investigated. First, logistic regression analysis was used to predict the odds of suffering depression based on FPCS and the raw scores. The analytical results showed that, via FPCS, the probability of correct classification of depressed and non-depressed was raised from 74.8% to 77.2%. Next, discrimination analysis was performed to classify the subjects according to the severity of depression into three categories: non-depression, depression with remission and depression without remission. The analytical results exhibited that, via FPCS, the probability of correct classification of severity of depression was raised from 71.2% to 80.7%. These two statistical analyses consistently show that FPCS exhibited higher predictive validity than did the raw score. That is, BDI scoring via FPCS makes more accuracy predictions for depression than raw score.
In Study Three, fuzzy c-means (FCM) clustering was applied to partition the sample according to severity of depression. To examine explore whether fuzzy-based clustering methods uncover the information inherent in the latent structure more accurately than crisp clustering, FCM, Wald’s method, and k-means method were performed. The analytical results reveal that the association between the original and classified membership generated by FCM was stronger than that of the Wald and k-means methods. Hence, FCM revealed the data structure most accurately.
Overall, FPCS has been consistently shown to be superior to raw scoring in terms of reliability, validity, and clustering accuracy. This study has empirically shown that fuzzy set theory is applicable to psychological research.
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Qualitative Distances and Qualitative Description of Images for Indoor Scene Description and Recognition in RoboticsFalomir Llansola, Zoe 28 November 2011 (has links)
The automatic extraction of knowledge from the world by a robotic system as human beings interpret their environment through their senses is still an unsolved task in Artificial Intelligence. A robotic agent is in contact with the world through its sensors and other electronic components which obtain and process mainly numerical information. Sonar, infrared and laser sensors obtain distance information. Webcams obtain digital images that are represented internally as matrices of red, blue and green (RGB) colour coordinate values. All this numerical values obtained from the environment need a later interpretation in order to provide the knowledge required by the robotic agent in order to carry out a task.
Similarly, light wavelengths with specific amplitude are captured by cone cells of human eyes obtaining also stimulus without meaning. However, the information that human beings can describe and remember from what they see is expressed using words, that is qualitatively.
The exact process carried out after our eyes perceive light wavelengths and our brain interpret them is quite unknown. However, a real fact in human cognition is that people go beyond the purely perceptual experience to classify things as members of categories and attach linguistic labels to them.
As the information provided by all the electronic components incorporated in a robotic agent is numerical, the approaches that first appeared in the literature giving an interpretation of this information followed a mathematical trend. In this thesis, this problem is addressed from the other side, its main aim is to process these numerical data in order to obtain qualitative information as human beings can do.
The research work done in this thesis tries to narrow the gap between the acquisition of low level information by robot sensors and the need of obtaining high level or qualitative information for enhancing human-machine communication and for applying logical reasoning processes based on concepts. Moreover, qualitative concepts can be added a meaning by relating them to others. They can be used for reasoning applying qualitative models that have been developed in the last twenty years for describing and interpreting metrical and mathematical concepts such as orientation, distance, velocity, acceleration, and so on. And they can be also understood by human-users both written and read aloud.
The first contributions presented are the definition of a method for obtaining fuzzy distance patterns (which include qualitative distances such as ‘near’, far’, ‘very far’ and so on) from the data obtained by any kind of distance sensors incorporated in a mobile robot and the definition of a factor to measure the dissimilarity between those fuzzy patterns. Both have been applied to the integration of the distances obtained by the sonar and laser distance sensors incorporated in a Pioneer 2 dx mobile robot and, as a result, special obstacles have been detected as ‘glass window’, ‘mirror’, and so on. Moreover, the fuzzy distance patterns provided have been also defuzzified in order to obtain a smooth robot speed and used to classify orientation reference systems into ‘open’ (it defines an open space to be explored) or ‘closed’.
The second contribution presented is the definition of a model for qualitative image description (QID) by applying the new defined models for qualitative shape and colour description and the topology model by Egenhofer and Al-Taha [1992] and the orientation models by Hernández [1991] and Freksa [1992]. This model can qualitatively describe any kind of digital image and is independent of the image segmentation method used. The QID model have been tested in two scenarios in robotics: (i) the description of digital images captured by the camera of a Pioneer 2 dx mobile robot and (ii) the description of digital images of tile mosaics taken by an industrial camera located on a platform used by a robot arm to assemble tile mosaics.
In order to provide a formal and explicit meaning to the qualitative description of the images generated, a Description Logic (DL) based ontology has been designed and presented as the third contribution. Our approach can automatically process any random image and obtain a set of DL-axioms that describe it visually and spatially. And objects included in the images are classified according to the ontology schema using a DL reasoner. Tests have been carried out using digital images captured by a webcam incorporated in a Pioneer 2 dx mobile robot. The images taken correspond to the corridors of a building at University Jaume I and objects with them have been classified into ‘walls’, ‘floor’, ‘office doors’ and ‘fire extinguishers’ under different illumination conditions and from different observer viewpoints.
The final contribution is the definition of a similarity measure between qualitative descriptions of shape, colour, topology and orientation. And the integration of those measures into the definition of a general similarity measure between two qualitative descriptions of images. These similarity measures have been applied to: (i) extract objects with similar shapes from the MPEG7 CE Shape-1 library; (ii) assemble tile mosaics by qualitative shape and colour similarity matching; (iii) compare images of tile compositions; and (iv) compare images of natural landmarks in a mobile robot world for their recognition.
The contributions made in this thesis are only a small step forward in the direction of enhancing robot knowledge acquisition from the world. And it is also written with the aim of inspiring others in their research, so that bigger contributions can be achieved in the future which can improve the life quality of our society.
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Avaliação do desempenho dos métodos de proteção contra a perda de excitação em geradores síncronos: uma contribuição utilizando a teoria dos conjuntos nebulosos / Performance evaluation of the loss of excitation protection methods in synchronous generator: a contribution using fuzzy set theoryMorais, Adriano Peres de 28 July 2008 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work aims to evaluate the performance of the loss of field protection methods in synchronous generators. The methods are introduced to make available in a single text the various ways to protect the synchronous generator against the loss of field. The conventional methods have some problems, and the main of them is the improper operation caused by the power stable oscillations. In order to solve or minimize the relay algorithm malfunction, two new methods of loss of field protection are proposed. The first is designed to increase the
operational area of the generator on steady state conditions, bounded by the conventional loss
of field protection. It was accomplished by modifying the operational characteristic of the mho relay, which is better coordinated with the generator capability curve. The second makes use of loss of field conception in a fuzzy set theory. With the objective to identify the
performance of each one, the methods were evaluated through computational simulations of loss of field and stable power oscillation. The methods were set and evaluated according to the generator parameters (Xd and X'd). Since, tests in three machines with different parameters were carried out. So it was possible to conclude that the methods do not behave the same way
for different generators parameters. On the other hand, the proposed technique, which is based on the fuzzy set theory was more efficient and not have been affected by the generator parameters and system considered. / Este trabalho visa avaliar o desempenho dos métodos de proteção contra a perda de excitação em geradores síncronos. Os métodos são apresentados de forma a tornar disponível em um único texto as diversas maneiras de se proteger o gerador síncrono contra a perda do seu sistema de excitação. Os métodos convencionais abordados apresentam alguns problemas, sendo o principal, a operação indevida causada por oscilações estáveis de potência. Visando
solucionar ou minimizar estes problemas, dois novos métodos de proteção contra a perda de excitação são propostos. O primeiro, objetivando aumentar a área operacional do gerador em regime permanente, restringida pela proteção contra a perda de excitação convencional, por meio de uma característica operacional modificada, melhor coordenada com a curva de capacidade do gerador. O segundo introduz os fundamentos clássicos da proteção contra a perda de excitação na teoria dos conjuntos nebulosos. Com o objetivo de se identificar o desempenho de cada um, os métodos existentes e os propostos foram avaliados por meio de
simulações computacionais de perda de excitação e oscilação estável de potência. Como os métodos possuem ajustes em função dos parâmetros do gerador protegido (Xd e X d),
realizaram-se testes com três máquinas de parâmetros distintos. Deste modo, foi possível concluir que os métodos não se comportam da mesma maneira para geradores de diferente porte. Por outro lado, a técnica proposta, que tem como base a teoria dos conjuntos nebulosos se mostrou eficiente e não teve seu desempenho afetado pelos parâmetros do gerador e do sistema considerado.
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