Made available in DSpace on 2014-06-11T19:34:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-10-11Bitstream added on 2014-06-13T18:45:51Z : No. of bitstreams: 1 almeida_lf_dr_guara.pdf: 1479231 bytes, checksum: d1b34509ec45ba1ae48a6450780e381d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Um importante aspecto no processo produtivo é proporcionar o funcionamento das máquinas o maior tempo possível sem o comprometimento na qualidade final do produto. Nesse sentido, a utilização de uma política de manutenção adequada se torna necessária para o monitoramento do desgaste dos componentes das máquinas a fim de aumentar o tempo de sua utilização sem comprometer a qualidade do produto. A manutenção baseada em condição se apresenta como a abordagem mais apropriada para esse controle. Dentre as diversas abordagens utilizadas para o desenvolvimento de programas para esse tipo de manutenção, as técnicas baseadas em Inteligência Artificial vêm se destacando no que diz respeito ao seu desempenho. Diante desse contexto, essa tese propõe uma Rede Neural Artificial, a qual, devidamente parametrizada, possibilita sua aplicação tanto para análise de vibrações quanto análise de partículas de desgaste. Para tanto, foi implementado um protótipo denominado NEURALNET-CBM, subdividido em dois módulos, Vibrações e Partículas. Os resultados dos testes mostram a efetividade da rede proposta, com um índice de acerto acima de 90% na classificação e identificação de defeitos e partículas de desgaste. / An important aspect in the production process is to ensure the operability of a machine as long as possible without interfering on the final quality product. In this way, the use of a suitable maintenance policy is critical for monitoring the wear of the machine components in order to increase your useful life without any compromise of the product quality. The Condition-Based Maintenance is presented as the most appropriate approach for this control. Among several methods used to develop systems for this type of maintenance, techniques Artificial Intelligence has been standing out in relation their performance. Therefore, this thesis proposes a Artificial Neural Network, which, properly parameterized, it makes possible its application for both vibration and wear particle analysis. For this, we implemented a prototype named NEURALNET-CBM, divided into two modules: Vibration and Particle. The test results show the effectiveness of the proposed network, with accuracy rate greater than 90% in classifying and identification of defects and wear particles.

PID is a prevalent tool of automatic control in both industry and home environment, and PID parameters are often forced to modify because of systematic service on the machines or systems, which is time-costing. The project aims to investigate the possibility of applying neural network and reducing PID configuration in controlling industry process, by means of establishing control models and comparing control performance between conventional PID method and improved PID control based on neural network where two built neural networks are considered as cores to adjust weights which result in the suggested PID parameters. Adaptive learning rate is also applied which is adjusted by the algorithm based on the error changes. Algorithm program is written in Siemens TIA Portal and simulated in Factory I/O. In general, the simulations after analysis have shown that the proposed model has a better performance than conventional PID in terms of steady state, deviations and consistency of control value except tuning time. In the future the author is dedicated to continue improving the mentioned model through quickening learning process, applying better activation function and modifying variable structure and so on.

Made available in DSpace on 2014-06-11T19:22:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-07-29Bitstream added on 2014-06-13T19:07:53Z : No. of bitstreams: 1 ferreira_ms_me_prud.pdf: 1897420 bytes, checksum: 1aede604709494154b2f75d18806c9fc (MD5) / O conhecimento da distribuição espacial da concentração de componentes da água é de fundamental importância para inferir a respeito dos processos ecológicos que ocorrem num sistema hídrico sendo, entretanto, de difícil obtenção. Dentre as variáveis que merecem atenção no monitoramento de ambientes aquáticos, destaca-se a clorofila a, a qual é uma substância presente em algas responsáveis pela fotossíntese, organismos que constituem a base da cadeia alimentar nesses ambientes. Por se tratar de um pigmento fotossintetizante, a clorofila a apresenta a propriedade de interagir com a radiação eletromagnética, e dessa interação resultam diferentes processos, identificáveis por meio de sensores remotos. Assim sendo, a presente pesquisa se propôs a desenvolver um método de inferência da concentração de clorofila a utilizando Redes Neurais Artificiais (RNA). Utilizou-se como dados de entrada para a inferência combinações de bandas espectrais de uma imagem World View-2 e valores de concentração de clorofila a obtidos com um fluorômetro de campo, o qual possibilitou uma amostragem densa na área de estudos. A imagem multiespectral foi corrigida radiometricamente, eliminando efeitos de instrumentação e atmosféricos. Ainda, efetuou-se uma suavização espectral em cada uma das bandas e foi avaliado se esse tratamento na imagem possibilitaria... / The knowledge of the spatial distribution of water components concentrations is of fundamental importance to infer about the ecological processes that occur in an aquatic system, however, is difficult to obtain it. Among the variables that deserve attention in the monitoring of aquatic environments, cite the chlorophyll a, which is a substance of photosynthetic algae, organisms that are the basis of the food chain in these environments. Because it is a photosynthetic pigment, chlorophyll a has the property to interact with electromagnetic radiation, and it results in different processes, identifiable through remote sensing. Thus, this research intended to develop a chlorophyll a concentration inference method using Artificial Neural Networks (ANN). As input for the inference, it was used combinations of World View-2 spectral bands and chlorophyll a concentration values obtained with a field fluorometer, which allowed a dense sampling in the study area. The multispectral imagery was radiometrically corrected, eliminating the instrumentation and atmospheric effects. Still, it was performed a spectral smoothing in each of the spectral bands and evaluated whether this treatment would give... (Complete abstract click electronic access below)

Orientador: Mauro Hugo Mathias / Banca: Alvaro Manoel Souza Soares / Banca: José Elias Tomazini / Banca: Francisco Carlos Parquet Bizarria / Banca: Carlos Henrique Netto Lahoz / Resumo: Um importante aspecto no processo produtivo é proporcionar o funcionamento das máquinas o maior tempo possível sem o comprometimento na qualidade final do produto. Nesse sentido, a utilização de uma política de manutenção adequada se torna necessária para o monitoramento do desgaste dos componentes das máquinas a fim de aumentar o tempo de sua utilização sem comprometer a qualidade do produto. A manutenção baseada em condição se apresenta como a abordagem mais apropriada para esse controle. Dentre as diversas abordagens utilizadas para o desenvolvimento de programas para esse tipo de manutenção, as técnicas baseadas em Inteligência Artificial vêm se destacando no que diz respeito ao seu desempenho. Diante desse contexto, essa tese propõe uma Rede Neural Artificial, a qual, devidamente parametrizada, possibilita sua aplicação tanto para análise de vibrações quanto análise de partículas de desgaste. Para tanto, foi implementado um protótipo denominado NEURALNET-CBM, subdividido em dois módulos, Vibrações e Partículas. Os resultados dos testes mostram a efetividade da rede proposta, com um índice de acerto acima de 90% na classificação e identificação de defeitos e partículas de desgaste. / Abstract: An important aspect in the production process is to ensure the operability of a machine as long as possible without interfering on the final quality product. In this way, the use of a suitable maintenance policy is critical for monitoring the wear of the machine components in order to increase your useful life without any compromise of the product quality. The Condition-Based Maintenance is presented as the most appropriate approach for this control. Among several methods used to develop systems for this type of maintenance, techniques Artificial Intelligence has been standing out in relation their performance. Therefore, this thesis proposes a Artificial Neural Network, which, properly parameterized, it makes possible its application for both vibration and wear particle analysis. For this, we implemented a prototype named NEURALNET-CBM, divided into two modules: Vibration and Particle. The test results show the effectiveness of the proposed network, with accuracy rate greater than 90% in classifying and identification of defects and wear particles. / Doutor

Made available in DSpace on 2014-12-17T14:55:19Z (GMT). No. of bitstreams: 1 JoseMAJ_TESE.pdf: 3560157 bytes, checksum: 2f20316c7b980a74bdb7b82e97e3bb43 (MD5) Previous issue date: 2014-03-24 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / In last decades, neural networks have been established as a major tool for the identification of nonlinear systems. Among the various types of networks used in identification, one that can be highlighted is the wavelet neural network (WNN). This network combines the characteristics of wavelet multiresolution theory with learning ability and generalization of neural networks usually, providing more accurate models than those ones obtained by traditional networks. An extension of WNN networks is to combine the neuro-fuzzy ANFIS (Adaptive Network Based Fuzzy Inference System) structure with wavelets, leading to generate the Fuzzy Wavelet Neural Network - FWNN structure. This network is very similar to ANFIS networks, with the difference that traditional polynomials present in consequent of this network are replaced by WNN networks. This paper proposes the identification of nonlinear dynamical systems from a network FWNN modified. In the proposed structure, functions only wavelets are used in the consequent. Thus, it is possible to obtain a simplification of the structure, reducing the number of adjustable parameters of the network. To evaluate the performance of network FWNN with this modification, an analysis of network performance is made, verifying advantages, disadvantages and cost effectiveness when compared to other existing FWNN structures in literature. The evaluations are carried out via the identification of two simulated systems traditionally found in the literature and a real nonlinear system, consisting of a nonlinear multi section tank. Finally, the network is used to infer values of temperature and humidity inside of a neonatal incubator. The execution of such analyzes is based on various criteria, like: mean squared error, number of training epochs, number of adjustable parameters, the variation of the mean square error, among others. The results found show the generalization ability of the modified structure, despite the simplification performed / Nas ?ltimas d?cadas, as redes neurais t?m se estabelecido como uma das principais ferramentas para a identifica??o de sistemas n?o lineares. Entre os diversos tipos de redes utilizadas em identifica??o, uma que se pode destacar ? a rede neural wavelet (ou Wavelet Neural Network - WNN). Esta rede combina as caracter?sticas de multirresolu??o da teoria wavelet com a capacidade de aprendizado e generaliza??o das redes neurais, podendo fornecer modelos mais exatos do que os obtidos pelas redes tradicionais. Uma evolu??o das redes WNN consiste em combinar a estrutura neuro-fuzzyANFIS (Adaptive Network Based Fuzzy Inference System) com estas redes, gerando-se a estrutura Fuzzy Wavelet Neural Network - FWNN. Essa rede ? muito similar ?s redes ANFIS, com a diferen?a de que os tradicionais polin?mios presentes nos consequentes desta rede s?o substitu?dos por redes WNN. O presente trabalho prop?e uma rede FWNN modificada para a identifica??o de sistemas din?micos n?o lineares. Nessa estrutura, somente fun??es waveletss?o utilizadas nos consequentes. Desta forma, ? poss?vel obter uma simplifica??o da estrutura com rela??o a outras estruturas descritas na literatura, diminuindo o n?mero de par?metros ajust?veis da rede. Para avaliar o desempenho da rede FWNN com essa modifica??o, ? realizada uma an?lise das caracter?sticas da rede, verificando-se as vantagens, desvantagens e o custo-benef?cio quando comparada com outras estruturas FWNNs. As avalia??es s?o realizadas a partir da identifica??o de dois sistemas simulados tradicionalmente encontrados na literatura e um sistema real n?o linear, consistindo de um tanque de multisse??es e n?o linear. Por fim, a rede foi utilizada para inferir valores de temperatura e umidade no interior de uma incubadora neonatal. A execu??o dessa an?lise baseia-se em v?rios crit?rios, tais como: erro m?dio quadr?tico, n?mero de ?pocas de treinamento, n?mero de par?metros ajust?veis, vari?ncia do erro m?dio quadr?tico, entre outros. Os resultados encontrados evidenciam a capacidade de generaliza??o da estrutura modificada, apesar da simplifica??o realizada

Submitted by Amanda Silva (amanda.osilva2@ufpe.br) on 2015-03-03T14:16:54Z No. of bitstreams: 2 Dissertação Mariel Cadena da Matta.pdf: 2355898 bytes, checksum: 9c0530af680cf965137a2385d949b799 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-03-03T14:16:54Z (GMT). No. of bitstreams: 2 Dissertação Mariel Cadena da Matta.pdf: 2355898 bytes, checksum: 9c0530af680cf965137a2385d949b799 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2013 / FACEPE / A Dosimetria citogenética empregando análise de cromossomos dicêntricos é o “padrão ouro” para estimativas da dose absorvida após exposições acidentais às radiações ionizantes. Todavia, este método é laborioso e dispendioso, o que torna necessária a introdução de ferramentas computacionais que dinamizem a contagem dessas aberrações cromossômicas radioinduzidas. Os atuais softwares comerciais, utilizados no processamento de imagens em Biodosimetria, são em sua maioria onerosos e desenvolvidos em sistemas dedicados, não podendo ser adaptados para microscópios de rotina laboratorial. Neste contexto, o objetivo da pesquisa foi o desenvolvimento do software ChromoSomeClassification para processamento de imagens de metáfases de linfócitos (não irradiados e irradiados) coradas com Giemsa a 5%. A principal etapa da análise citogenética automática é a separação correta dos cromossomos do fundo, pois a execução incorreta desta fase compromete o desenvolvimento da classificação automática. Desta maneira, apresentamos uma proposta para a sua resolução baseada no aprimoramento da imagem através das técnicas de mudança do sistema de cores, subtração do background e aumento do contraste pela modificação do histograma. Assim, a segmentação por limiar global simples, seguida por operadores morfológicos e pela técnica de separação de objetos obteve uma taxa de acerto de 88,57%. Deste modo, os cromossomos foram enfileirados e contabilizados, e assim, a etapa mais laboriosa da Dosimetria citogenética foi realizada. As características extraídas dos cromossomos isolados foram armazenadas num banco de dados para que a classificação automática fosse realizada através da Rede Neural com Funções de Ativação de Base Radial (RBF). O software proposto alcançou uma taxa de sensibilidade de 76% e especificidade de 91% que podem ser aprimoradas através do acréscimo do número de objetos ao banco de dados e da extração de mais características dos cromossomos.

Two questions are addressed: 1) whether a dream is meaningful as a whole, or whether the scenes are separate and unconnected, and 2) whether dream images are an epiphenomenon of a functional physiologicaL process of REM sleep, or whether they are akin to waking thought. Theories of REM sleep as a period of information-processing are reviewed. This is Linked with work on the relationship between dreaming and creativity, and between memory and imagery. Because of the persuasive evidence that REM sleep is implicated in the consolidation of memories there is a review of recent work on neural associative network models of memory. Two theories of dreams based on these models are described, and predictions with regard to the above two questions are made. Psychological evidence of relevance to the neural network theories is extensively reviewed. These predictions are compared with those of the recent application of structuralism to the study of dreams, which is an extension from its usual field of mythology and anthropology. The different theories are tested against four nights of dreams recorded in a sleep Lab. The analysis shows that not only do dreams concretise waking concerns as metaphors but that these concerns are depicted in oppositional terms, such as, for example, inside/outside or revolving/static. These oppositions are then permuted from one dream to the next until a resolution of the initial concern is achieved at the end of the night. An account of the use of the single case-study methodology in psychology is given, in addition to a replication of the analysis of one night's dreams by five independent judges. There is an examination of objections to the structuralist methodology, and of objections to the paradigm of multiple dream awakenings. The conclusion is drawn that dreams involve the unconscious dialectical step-by-step resolution of conflicts which to a great extent are consciously known to the subject. The similarity of dreams to day-dreams is explored, with the conclusion that the content of dreams is better explained by an account of metaphors we use when awake and by our daily concerns, than by reference to the physiology of REM sleep. It is emphasised that dreams can be meaningful even if they do not have a function.

The competition in the global market is accelerating rapidly because of less technological gap, matured manufacturing level, and various changing customer needs. Increasingly customers choose products in terms of experience desires, psychological desires and whether the products can reflect their values, in addition to the main product functions. Moreover, there are a large number of small and medium sized manufacturing companies in the developing countries. OEM (Original Equipment Manufacturer) and simple mass production cannot generate good value for these manufacture companies, and they have been seeking new opportunities to create higher value for their products/services and satisfy different needs of customers. Mass customization is one of the main business forms in the future, which can best meet the needs of individual customer, especially psychological needs. The key to mass customization is to provide enough modules to meet individual needs with a limited cost increase. The problem has been how to identify the real user needs and individual differences. The purpose of this research is to develop a sound design methodology based upon the current product design theories and practices for future product innovation and sustainable growth of small and medium sized manufacturing enterprises. The research focuses on the user-product cognitive behaviours and the relationship between human attributes and product features. Orthogonal experiment, eye tracking technology and artificial neural network have been successfully applied in this research. The research has developed a user needs hierarchy model and added value hierarchy model, and a robust theoretical basis to predict and evaluate (individual) user needs for product design. The research has further made the following contributions: 1) The relationship between human attributes and product features has been established, which can help designers understand the differences of various customer groups; 2) The different effects of various influence factors on people’s cognition and preference choice based on vision have been analysed and discussed; 3) A new method to identify, cluster, and combine common needs and personalized needs in early design stage for mass customization has been developed; 4) The research results can be reused in the future design of the same or similar kind of products.

In this thesis I look into how one can train and run an artificial neural network using Compute Shader and what kind of performance can be expected. An artificial neural network is a computational model that is inspired by biological neural networks, e.g. a brain. Finding what kind of performance can be expected was done by creating an implementation that uses Compute Shader and then compare it to the FANN library, i.e. a fast artificial neural network library written in C. The conclusion is that you can improve performance by training an artificial neural network on the compute shader as long as you are using non-trivial datasets and neural network configurations.

Yacht races are won by good sailors racing fast boats. A good skipper takes decisions at key moments of the race based on the anticipated wind behaviour and on his position on the racing area and with respect to the competitors. His aim is generally to complete the race before all his opponents, or, when this is not possible, to perform better than some of them. In the past two decades some methods have been proposed to compute optimal strategies for a yacht race. Those strategies are aimed at minimizing the expected time needed to complete the race and are based on the assumption that the faster a yacht, the higher the number of races that it will win (and opponents that it will defeat). In a match race, however, only two yachts are competing. A skipper’s aim is therefore to complete the race before his opponent rather than completing the race in the shortest possible time. This means that being on average faster may not necessarily mean winning the majority of races. This thesis sets out to investigate the possibility of computing a sailing strategy for a match race that can defeat an opponent who is following a fixed strategy that minimises the expected time of completion of the race. The proposed method includes two novel aspects in the strategy computation: A short-term wind forecast, based on an Artificial Neural Network (ANN) model, is performed in real time during the race using the wind measurements collected on board. Depending on the relative position with respect to the opponent, decisions with different levels of risk aversion are computed. The risk attitude is modeled using Coherent Risk Measures. The proposed algorithm is implemented in a computer program and is tested by simulating match races between identical boats following progressively refined strategies. Results presented in this thesis show how the intuitive idea of taking more risk when losing and having a conservative attitude when winning is confirmed in the risk model used. The performance of ANN for short-term wind forecasting is tested both on wind speed and wind direction. It is shown that for time steps of the order of seconds and adequate computational power ANN perform better than linear models (persistence models, ARMA) and other nonlinear models (Support Vector Machines). The outcome of the simulated races confirms that maximising the probability of winning a match race does not necessarily correspond to minimising the expected time needed to complete the race.