Journal of Intelligent & Fuzzy Systems - Volume 13, issue 2-4

Authors: Macêdo, Renata A. | da Silva-Filho, Donato | Coury, Denis V. | Carneiro, Adriano A.F.M. | de Carvalho, André C.P.L F.

Article Type: Research Article

Abstract: The presence of voltage and current waveform distortion is generally expressed in terms of harmonic frequencies. These distortions are not appreciated because they are responsible for equipment misoperation and damage. The potential harmonic effects on power equipment and system operation have become a concern for utilities. As a consequence, harmonics can no longer be ignored in industrial power. Therefore, precise harmonic identification is a very important task in order to eliminate these undesirable effects. This paper …presents a novel approach to identifying harmonics in power system distorted waveforms. The proposed method is based on Genetic Algorithms, which is an optimization technique inspired by genetics and natural evolution. GOOAL, a specially designed intelligent algorithm for optimization problems, was successfully implemented and tested. Two kinds of representations concerning chromosomes were utilized: binary and real. The results obtained show that the proposed method is more precise than the traditional Fourier Transform, especially considering the real representation of the chromosomes. Show more

Citation: Journal of Intelligent & Fuzzy Systems, vol. 13, no. 2-4, pp. 167-175, 2002

Authors: Palmer, Alex S. | Razaz, Moe | Mandic, Danilo P.

Article Type: Research Article

Abstract: When using a regularized approach for image restoration there is always a compromise between image sharpness and noise suppression. Since noise is removed at the cost of edges and detail within the image, there is a need to introduce algorithms which exhibit some kind of memory and cater for the spatial structure of an image. To this cause, we introduce an efficient restoration algorithm, based on a modified adaptive Hopfield neural network. The algorithm is capable …of spatially regularizing an image and thereby preserving data fidelity around edges while simultaneously suppressing noise in more noticeable areas such as smooth regions. The proposed method demonstrates an improvement in restoration quality over existing adaptive and non-adaptive approaches. This is illustrated with simulations on benchmark images under varying noise levels. Show more

Citation: Journal of Intelligent & Fuzzy Systems, vol. 13, no. 2-4, pp. 177-185, 2002