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The design of electromagnetic devices is generally multimodal, multidimensional, and constrained. Its simulation-based feature makes traditional optimization algorithms unsuitable to use; whereas metaheuristic approaches are good choices for tackling such problems. Since many electromagnetic design problems require excessive computer resources even on modern computers, attempts to improve the efficiency and effectiveness of metaheuristic approaches are very challenging for designers. This paper proposes a modification of artificial bee colony (ABC) algorithm. The design philosophy of this algorithm is to promote the convergence rate of ABC. The properties of the modified ABC algorithm are analyzed by testing, first, on two mathematical functions. The proposed algorithm is then applied to solve a loudspeaker design problem using FEM. Promising performance is obtained when compared with those using original ABC, genetic algorithm, particle swarm optimization, and differential evolution algorithms. [ABSTRACT FROM AUTHOR]

Optimal design problems of electromagnetic devices are generally multimodal, nondifferentiable, and constrained. This makes metaheuristic algorithm a good choice for solving such problems. In this paper, a newly developed metaheuristic algorithm is presented to address the aforementioned issues. The proposed algorithm is based on the paradigm of artificial bee colony (ABC). A drawback of the original ABC algorithm is because its solution variation is only 1-D, as this decreases its convergence speed. In this paper, a one-position inheritance scheme is proposed to alleviate this drawback. An opposite directional (OD) search is also proposed to accelerate the convergence of the ABC algorithm. The novel algorithm is applied to both TEAM Workshop problem 22 and a loudspeaker design problem. Both discrete and continuous cases of problem 22 are tested. The effectiveness and efficiency of the proposed algorithm are demonstrated by comparing its performance with those of the original ABC, an improved ABC known as Gaussian ABC, and differential evolution algorithms. [ABSTRACT FROM PUBLISHER]

A multi-slice finite element model for wireless magnetic resonant energy transfer systems with circular spiral tape coils is presented. As the system is constructed using distributive capacitance, it is difficult to determine the parameters in the equivalent circuits analytically. To address the aforementioned problem, a multi-slice axisymmetric finite element method (FEM) is applied to analyze this wireless power transfer system. The merits of the proposed method are that three-dimensional FEM is not required and yet the distributive capacitances among the coils can be fully included in the proposed two-dimensional model. Compared with normal axisymmetric FEM without multi-slices, the proposed method can include the effect of distributive capacitance to produce more precise solutions. The proposed method is validated against experimental data. [ABSTRACT FROM AUTHOR]

Apaf-1 plays a crucial role in the cytochrome c/dATP-dependent activation of caspase-9 and -3. We found that the human myeloid leukemic K562 cells were more resistant to cytochrome c-induced activation of caspase-9 and -3 in a cell-free system compared with the human T-lymphoblastic subclone CEM/VLB(100) cells. Apaf-1 cDNA sequencing revealed an additional insert of 11 aa between the CARD and CED-4 (ATPase) domains in K562 cells, which was identical to the sequence of Apaf-1XL. Immunoprecipitation of Apaf-1 with caspase-9 after a cell-free reaction demonstrated that Apaf-1XL in the K562 cell line showed a lower binding ability to caspase-9 compared with Apaf-1L protein. The resistance of K562 cells to cytochrome c-dependent apoptosis may be partly due to this Apaf-1XL form. These results suggest that the additional insert between CARD and CED-4 domains might affect Apaf-1 recruitment of caspase-9 during apoptosis., (Copyright 2001 Academic Press.)