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Differential evolution (DE) is a promising evolutionary algorithm for solving optimal reactive power flow problems, but it requires relatively large population to avoid premature convergence. In order to overcome this disadvantage, a novel decomposition and coordination method based on the cooperative co-evolutionary architecture and the voltage-var sensitivity-based power system decomposition technique is proposed and incorporated with DE in this paper. It is implemented with a three-level parallel computing topology on a PC-cluster. Based on the IEEE 118-bus system test case, the effectiveness of the proposed method has been verified by comparison with the parallel basic DE not using the decomposition and coordination technique. Index Terms--Cooperative co-evolution, differential evolution (DE), optimal reactive power flow (ORPF), parallel computing, power system decomposition.

Nonlinear differential equations for the reflection coefficients of an inhomogeneous lossy medium illuminated by both TE-polarized and TM-polarized electromagnetic plane waves are derived using a microwave networking technique, which can be approximately solved by a nonlinear renormalization method. Considering the equivalent microwave network of the permittivity profile discontinuity at the interface of free space with the medium, two novel inverse scattering solutions for the permittivity profile and the conductivity profile are further investigated in closed forms. Closed-form and numerical reconstruction examples show the availability of this scheme.

A novel matrix perturbation technique for the matrix equation (A)(u) = (b) is presented. One of its applications, the computation of internal fields in a three-dimensional arbitrarily shaped heterogeneous biological body illuminated by a plane wave, is further investigated by using the technique. If we regard a normal biological body as the primary model and store its computation results, when small perturbations in the dielectric characteristics or the shape of the body occur, the internal fields in the perturbed biological body can be rapidly computed using the stored results. Compared with the usual moment methods, the new technique has equivalent precision, yet takes only 1/70 the execution time. This technique is especially suitable for the pathological cases in which the dielectric characteristics or the shape of the biological body vary sequently.

A weak collision RRKM-Master Equation (ME) model has shown that hot intermediates might react while they are undergoing stepwise relaxation through weak collisions, even in solution. The master equation has provided a computationally tractable model with considerable predictive power that is used to examine whether stepwise collisional relaxation is prevalent in other polyatomic systems.

The optical properties of Au-doped rhenium diselenide single crystals are studied. The parameters describing the temperature variations in the excitonic transitions in Re[Se.sub.2]:Au layer crystals are evaluated.