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This thesis presents appropriate model structures for fuzzy systems, and accompanies these model structures with parameter-level learning and structure-level learning. The emphasis of the present exercise is on basic principles of the design, operating characteristics, and adaptation of fuzzy systems. In order to incorporate adaptation into fuzzy systems, a refined mathematical model format for fuzzy systems is developed in such a way that the fuzzy logical rules in the systems are parameterized. Two general learning paradigms are considered: competitive learning and supervised learning. By incorporating competitive learning into fuzzy system, we demonstrate that fuzzy systems can be used effectively for categorization and clustering of unlabeled input patterns. Methods for dynamically adjusting the parameters and structures based on fuzzy competitive learning are discussed. To facilitate system design, we present several supervised learning algorithms for adjusting parameters. Also, a novel structure-level supervised learning algorithm that is able to self-organize the number of fuzzy rules is proposed. The results of simulations reveal that the proposed parameter-level as well as structure- level competitive learning and supervised learning algorithms are practically feasible. Potential applications include function approximation, pattern classification, vector quantization, clustering, and system identification.
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