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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.
131

NOVEL APPROACHES FOR STATISTICAL PROCESS CONTROL CHARTS PATTERN RECOGNITION

el homani, Abdellatif 01 May 2010 (has links)
Fast and accurate recognition of the Statistical Control Chart Patterns (SPCCP) is significant for supervising manufacturing processes to accomplish better control and to make high value products. SPCCP can display eight kinds of patterns: normal, stratification, systematic, increasing trend, decreasing trend, up shift, down shift and cyclic. With the exception of the natural pattern, all other patterns indicate that the supervised manufacturing process is not performing properly and actions need to be taken to correct the problems. This research proposes new approaches, neural networks and neural-fuzzy systems, to the (SPCCP) recognition. This dissertation also investigates the use of features extracted from statistical analysis for simple patterns, and wavelet analysis for concurrent patterns as the components of the input vectors. Results based on simulated data show that the proposed approaches perform better than conventional approaches. Our work concluded that the extracted features improve the performance of the proposed recognizer systems.
132

A Fuzzy Rule-Based Model for Predicting Precipitation in the Marion, Illinois Station Area

Alexander, Cindy-Ann Patricia 01 August 2012 (has links)
The purpose of this paper is present the results of a developed, and implemented a Fuzzy rule based model to determine the probability of precipitation in the Marion Illinois area during the summer months. The model employs fuzzy logic and the results are compared to actual data to measure how reliable and viable this method is as an option in the precipitation prediction. Researchers, over the years, have been developing models for simulating, predicting and analyzing atmospheric phenomena, in order to accurately determine their immediate and long term effects on the environment and the quality of human life, such as in agriculture, ecosystem evolution, biodiversity, and disaster preparedness (decision support systems: drought/ warning or flash floods). To simulate global climate changes, researchers use General Circulation Models (GCMs). These have been developed using numerical weather predictions. These models are very useful for global impact studies such as global warming, but they are limited if applied to regional scenarios. This is because they are not able to neither simulate the local effects nor accurately present spatial and temporal resolutions. Continued work to improve the efficiency of these systems has led to the development of various models. Improvements have come in the form of Regional Climate Models; they have higher resolution and take into account orographic effects. These models use downscaling techniques, which bridge the gap between the global climate simulations and regional climate impact assessment. This paper presents the implementation of a fuzzy rule-based downscaling technique with specific application to the Marion, Illinois area. It shows that this method has the distinct advantage of being both computation and resource inexpensive while producing accurate information in a timely manner.
133

Application of artificial intelligence for accurate fault location on transmission systems

Joorabian, M. January 1996 (has links)
No description available.
134

Desenvolvimento de aplicações em medicina e agronomia utilizando lógica fuzzy e neuro fuzzy

Silva, Aldo Antonio Vieira da [UNESP] 28 February 2014 (has links) (PDF)
Made available in DSpace on 2014-11-10T11:09:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-28Bitstream added on 2014-11-10T11:58:00Z : No. of bitstreams: 1 000794270.pdf: 1454507 bytes, checksum: 21c1e569f66804233a47b876585652ce (MD5) / O presente trabalho propõe duas novas metodologias de desenvolvimento: uma na área de medicina, no diagnóstico de hérnia inguinal utilizando a lógica fuzzy e outra, na área da agronomia, para estimação da produção de trigo utilizando o modelo de inferência adaptativo neuro fuzzy. Na primeira foi desenvolvido um aplicativo para dispositivos móveis, smartphones e tablets, auxiliando a tomada de decisão no diagnóstico de pacientes com suspeita de hérnia na região inguinal. Para isso, utilizou-se a linguagem JAVA juntamente com a biblioteca lógica fuzzy, denominada jfuzzylogic, e o sistema operacional Android para o desenvolvimento da aplicação. Para validar o aplicativo, utilizou-se a coleta de dados, via questionário, envolvendo 30 pacientes entrevistados em consulta médica. Como resultado, observou-se que o diagnóstico realizado pela equipe médica e o diagnóstico com o auxílio do aplicativo móvel, mostraram-se equivalentes nos casos dos pacientes acometidos com hérnia da região inguinal. Este software será disponibilizado gratuitamente, via web, para os profissionais da área da saúde. Já na segunda, investigou-se a habilidade de se desenvolver um modelo de inferência adaptativo neuro fuzzy para estimação da produtividade de trigo (Triticum aestivum) em função da adubação nitrogenada, com base em dados experimentais de cultivares de trigo, avaliada durante dois anos, em Selvíria-MS. Através dos dados de entrada e saída, o sistema de inferência neuro fuzzy adaptativo apreende e posteriormente pode estimar um novo valor de produção de trigo baseada em doses diferenciadas de nitrogênio. Os resultados mostraram que o sistema neuro fuzzy é viável para desenvolver um modelo de predição para estimar a produtividade de trigo em função da dose de nitrogênio. A produção estimada através do sitema neuro fuzzy proporcionou um erro RMSE (Raiz Quadrada do Erro Médio ... / This work proposes two new application methods: one in the area of biomedical engineering in the diagnosis of inguinal hernias using fuzzy logic and another in the area of agriculture to estimate the wheat productivity using an adaptive neuro fuzzy inference system. The first was an application developed for mobile devices, smartphones and tablets, to assist decision making in the diagnosis of patients with suspected inguinal hernia. It was used the Java language together with the fuzzy logic library, denominated jfuzzylogic and the Android operating system for the application development. To validate the application it was used data obtained via questionnaire, involving 30 patients interviewed in medical consultation. As a result, it was observed that the diagnosis made by the medical team and diagnosis with the aid of the mobile application, were equivalent in cases of affected patients with hernia in the inguinal region. This software is available free of charge via the web, for professionals in the health field. In the second application method, it was investigated the ability to develop an adaptive neuro fuzzy inference system for estimating the productivity of wheat (Triticum aestivum) in relation to the nitrogen fertilization, based on experimental data of wheat cultivars during two years, in Selvíria-MS. Through the data input and output, the system of adaptive neuro fuzzy inference learns and subsequently can estimate a new value of wheat production based on different doses of nitrogen. The results showed that the neuro fuzzy system is feasible to develop a prediction model to estimate the productivity of wheat in relation to nitrogen rates. The RMSE (Root Mean Square Error) error of the estimated wheat productivity using the neuro fuzzy system was smaller than that obtained with the quadratic regression method, that is usually used in this kind of estimated, and also the relation between ...
135

Análise morfológica de imagens e classificação de aberrações cromossômicas por meio de lógica fuzzy / Morphological images analysis and chromosomic aberrations classification based on fuzzy logic

SOUZA, LEONARDO P. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:34:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:51Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
136

Desenvolvimento e análise de um índice de sustentabilidade energética utilizando lógica fuzzy

SANTOS, FRANCISCO C.B. dos 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:33Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:40Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
137

Análise morfológica de imagens e classificação de aberrações cromossômicas por meio de lógica fuzzy / Morphological images analysis and chromosomic aberrations classification based on fuzzy logic

SOUZA, LEONARDO P. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:34:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:51Z (GMT). No. of bitstreams: 0 / Este trabalho desenvolve uma metodologia para a automação da análise morfológica de imagens de cromossomos humanos irradiados no reator nuclear IEA-R1 (localizado no Instituto de Pesquisas Energéticas e Nucleares, IPEN, em São Paulo, Brasil) e, portanto, sujeitos a aberrações morfológicas. Esta metodologia se propõe a auxiliar na identificação, caracterização e classificação de cromossomos pelo profissional citogeneticista. O desenvolvimento da metodologia inclui a elaboração de um aplicativo baseado em técnicas de inteligência artificial utilizando Lógica Fuzzy e técnicas de processamento de imagens. O aplicativo desenvolvido foi denominado de CHRIMAN e é composto de módulos que contêm etapas metodológicas que suprem aspectos importantes para a obtenção de uma análise automatizada. A primeira etapa é a padronização dos procedimentos de aquisição das imagens digitais bidimensionais de metáfases através do acoplamento de uma câmera fotográfica digital comercial comum à ocular do microscópio utilizado na análise metafásica convencional. A segunda etapa é relativa ao tratamento das imagens obtidas através da aplicação de filtros digitais, armazenamento e organização das informações tanto do conteúdo da imagem em si, como das características extraídas e selecionadas, para posterior utilização nos algoritmos de reconhecimento de padrões. A terceira etapa consiste na utilização do banco de imagens digitalizadas e informações extraídas e armazenadas para a identificação dos cromossomos, sua caracterização, contagem e posterior classificação. O acerto no reconhecimento das imagens cromossômicas é de 93,9%. Esta classificação é baseada nos padrões encontrados classicamente em Buckton [1973], e possibilita o auxílio ao geneticista no procedimento de análise dos cromossomos com diminuição do tempo de análise e criando condições para a inclusão deste método num sistema mais amplo de avaliação de danos causados às células pela exposição à radiação ionizante. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
138

Desenvolvimento e análise de um índice de sustentabilidade energética utilizando lógica fuzzy

SANTOS, FRANCISCO C.B. dos 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:33Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:40Z (GMT). No. of bitstreams: 0 / A questão do Desenvolvimento Sustentável é um dos temas mais falados na atualidade, e a busca do seu entendimento um grande desafio aos pesquisadores. Mas buscar seu entendimento e as relações das dimensões que o compõe (dimensão econômica, social, ambiental e institucional) não é o único desafio. Mensurar o caminho do desenvolvimento de uma sociedade é um desafio igualmente grande, principalmente devido as intrincadas relações entre meio ambiente, sociedade e economia. Este trabalho apresenta uma nova abordagem na construção de um índice sintético de desenvolvimento sustentável do ponto de vista da sustentabilidade energética. Esta metodologia se baseou em arquétipos matemáticos estruturados na Lógica Fuzzy, permitindo assim incorporar novas bases de conhecimento, mesmo que com definições vagas. O resultado final é a criação de um Índice de Sustentabilidade Energética que pode ser acompanhado no tempo, e que permite comparações entre países, já que na sua construção utiliza-se a base de dados do Guia de Indicadores Energéticos de Desenvolvimento Sustentável da Agência Internacional de Energia Atômica, que apresenta uma metodologia mundialmente aceita de indicadores energéticos. Este índice foi concebido para se parecido com outros indicadores como Índice de Desenvolvimento Humano (IDH) elaborado pela Organização das Nações Unidas, o que permite um fácil entendimento, por ser um número entre zero e um. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
139

Development of a Control and Monitoring Platform Based on Fuzzy Logic for Wind Turbine Gearboxes

Chen, Wei January 2012 (has links)
It is preferable that control and bearing condition monitoring are integrated, as the condition of the system should influence control actions. As wind turbines mainly work in remote areas, it becomes necessary to develop a wireless platform for the control system. A fuzzy system with self-tuning mechanism was developed. The input speed error and speed change were selected to control the shaft speed, while the kurtosis and peak-to-peak values were used as another set of inputs to monitor the bearing conditions. To enhance effectiveness, wait-and-see (WAS) logic was used as the pre-processing step for the raw vibration signal. The system was implemented on the LabVIEW platform. Experiments have shown that the system can effectively adjust motor rotating speed in response to bearing conditions. For future studies, more advanced fault detection methods can be integrated with proper tuning mechanisms to enrich the performance and function of the controller.
140

Ensemble Fuzzy Belief Intrusion Detection Design

Chou, Te-Shun 13 November 2007 (has links)
With the rapid growth of the Internet, computer attacks are increasing at a fast pace and can easily cause millions of dollar in damage to an organization. Detecting these attacks is an important issue of computer security. There are many types of attacks and they fall into four main categories, Denial of Service (DoS) attacks, Probe, User to Root (U2R) attacks, and Remote to Local (R2L) attacks. Within these categories, DoS and Probe attacks continuously show up with greater frequency in a short period of time when they attack systems. They are different from the normal traffic data and can be easily separated from normal activities. On the contrary, U2R and R2L attacks are embedded in the data portions of the packets and normally involve only a single connection. It becomes difficult to achieve satisfactory detection accuracy for detecting these two attacks. Therefore, we focus on studying the ambiguity problem between normal activities and U2R/R2L attacks. The goal is to build a detection system that can accurately and quickly detect these two attacks. In this dissertation, we design a two-phase intrusion detection approach. In the first phase, a correlation-based feature selection algorithm is proposed to advance the speed of detection. Features with poor prediction ability for the signatures of attacks and features inter-correlated with one or more other features are considered redundant. Such features are removed and only indispensable information about the original feature space remains. In the second phase, we develop an ensemble intrusion detection system to achieve accurate detection performance. The proposed method includes multiple feature selecting intrusion detectors and a data mining intrusion detector. The former ones consist of a set of detectors, and each of them uses a fuzzy clustering technique and belief theory to solve the ambiguity problem. The latter one applies data mining technique to automatically extract computer users’ normal behavior from training network traffic data. The final decision is a combination of the outputs of feature selecting and data mining detectors. The experimental results indicate that our ensemble approach not only significantly reduces the detection time but also effectively detect U2R and R2L attacks that contain degrees of ambiguous information.

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