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In this paper, we consider the problem of modeling the timing error process in magnetic recording systems. We propose a discrete- valued Markov model for the timing error process, and design two methods (data-aided and nondata-aided), based on the Baum-Welch algorithm, to extract the model parameters from the readback waveforms. The channel model we consider is an intersymbol interference (ISI) channel with additive Gaussian noise. The continuous-time readback signal at the output of the channel is sampled at baud-rate. Simulation results show that the estimated parameters are close to the actual values and the convergence is attained in a few iterations of the Baum-Welch algorithm. We also demonstrate the usefulness of the accurate model extraction by comparing a fine-tuned Markov timing recovery loop to the standard Mueller and Muller detector with a tuned second-order loop filter. [ABSTRACT FROM AUTHOR]

This paper proposes the real-coded clonal selection algorithm (RCSA) for use in electromagnetic design optinilzation. Some features of the algorithm, such as the number of clones, mutation range, and the fraction of the population selected each generation are discussed. The TEAM Workshop problem 22 is investigated, in order to illustrate the performance of the algorithm in a real electromagnetic problem. The results obtained, a set of optimal solutions representing a broader range of options for the designer, are compared with those achieved by a genetic algorithm, showing the efficiency of the RCSA in practical optimization problems. [ABSTRACT FROM AUTHOR]

This paper deals with some aspects of performance of the symmetric successive over-relaxation preconditioner in a distributed environment. The details of distributed formulation of the preconditioner are presented. Some performance metrics are compared and discussed for the message passing interface implementation of the algorithm. The properties of the solver are estimated for concurrent three-dimensional formulation of the finite-element time-domain method. The analyzed benchmark models are approximated by tetrahedral first order Whitney elements. [ABSTRACT FROM AUTHOR]

This paper presents a Jiles-Atherton hysteresis model identification method based on a partnership of heuristic techniques and fuzzy logic (softcomputing). Two different soft- computing approaches are proposed and analyzed: a partnership between genetic algorithms (GAs) and fuzzy logic (FL) and one between GAs and simulated annealing (SA). Validations of both symmetric (saturated or minor loops) and asymmetric loops are described. [ABSTRACT FROM AUTHOR]

In this paper; a novel algorithm for multimodal function optimization is proposed, based on the concept of evolution strategy. A new concept, named restricted evolution, shows more improved characteristics than conventional approaches that have been used for multimodal function optimization. The efficiency and usefulness of the proposed method will be verified by the application to various cases including practical optimization problems. [ABSTRACT FROM AUTHOR]

The integrated radial basis function (IREF) network has been reported is an efficient algorithm to study the performance of brushless dc motors. However, such an algorithm cannot be implemented readily since it is difficult to lute-tune or even to find the undetermined coefficients in the integrated RBF network. In this paper, a novel auto-tuning algorithm that can effectively guarantee the automatic implementation of the integrated RBF network of a brushless dc motor is reported. [ABSTRACT FROM AUTHOR]

In electrical impedance tomography (EIT), cross-sectional resistivity distribution is reconstructed using current and voltage measurements made from the boundary. In. this paper, a novel adaptive mesh-grouping scheme is presented to enhance the spatial resolution of the Gauss-Newton algorithm in two-phase fields. Experimental results are provided to illustrate the effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

This paper presents a method for checking the connectivity of a set of finite elements and for dividing the set into simply connected subsets. The algorithm is based on expansion from a simply connected subset. The algorithm could be used to determine cut surfaces, but it is shown that simply connected subsets are more suitable in practice. [ABSTRACT FROM AUTHOR]