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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.

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.

Anion-exchange membrane fuel cells possess several important advantages, and have attracted a lot of attention. In this paper, the characteristic of different type anion-exchange membrane were introduced. In view of the ion conductivity and stability of anion-exchange membrane, these anion-exchange membranes based on polybenzimidazole, polytetrafluoroethylen polysulfone, polyvinyl alcohol/poly(vinylpyrrolidone) blend membrane, poly(ethylene-co-vinyl benzyl chloride) (LDPE-co-VBC) will be the potential polymer electrolyte for anion-exchange membrane fuel cells. [ABSTRACT FROM AUTHOR]

Parallel-plates enthalpy exchangers are one of the most commonly encountered energy recovery devices that are used to simultaneously transfer both sensible heat and moisture between fresh air and exhaust ventilation. In this investigation, an application scale parallel-plates enthalpy exchangers is manufactured. The enthalpy exchanger is tested with an applicable experimental set-up. The performances of sensible、latent and total energy exchanging have been investigated experimentally under various operating conditions. The sensible, latent and enthalpy effectiveness increase with an increase of the fresh air temperature. The sensible effectiveness is constant at 74% when the fresh air relative humidity increases. However, the latent effectiveness increases with an increase of the relative humidity. [ABSTRACT FROM AUTHOR]

Abstract: Occurrence and methods for the removal of nonylphenolic compounds in drinking water have been gaining increased attention due to their widespread presence in natural water and the potential health risks from the consumptions of drinking water. The purpose of this study was to assess the occurrence of nonylphenol (NP), octylphenol (OP), and bisphenol-A (BPA) in water sources and treated water in Taiwan, to evaluate the treatment efficiencies of these compounds in both the conventional (coagulation, sedimentation, filtration and chlorination) and advanced treatment processes. The treatment efficiencies of these chemicals were assessed based on their concentrations in water sources, and the results were verified with laboratory simulated treatment processes. A survey of NP, OP, and BPA in 11 Taiwanese water sources showed that all of them could be identified in most of the sampled sources, and that higher concentrations of NP were found when the raw water was contaminated by domestic wastewater. However, higher treatment efficiency could be observed when the NP concentration in water source is high. Laboratory simulation studies of conventional treatment processes showed that chlorination played an important role in the degradation of NP in raw water. Treatment efficiencies of 60%–90% were achieved for NP removal when sufficient chlorine dosages were applied to satisfy chlorine demands. However, results also showed that conventional coagulation and rapid filtration processes were less effective in the reduction of phenolic compounds in water. [Copyright &y& Elsevier]

A generalized formulation of Cauchy method for multiplexer rational model extraction is presented in this paper. This new technique can extract the multiplexer rational models from either measurement or electromagnetic simulation results. The generalized formulation of Cauchy method takes into account the relationship between the transmission coefficients and reflection coefficients of each channel filter. It is suitable for multiplexers whose chan-nel filters are connected through resonating junction. The total least square method is applied to solve the system matrix. The new technique presented in this paper is suitable for lossless case as well as lossy case and is verified by lossless triplexer and circuit simu-lation lossy triplexer examples successfully. [ABSTRACT FROM AUTHOR]

An improved hybrid method of moments and physical-optics (MOM-PO) method is presented to analyse an antenna around an electrically large platform modelled with non-uniform rational B-spline (NURBS) surfaces. A Ludwig integral combined with stationary phase method is used to calculate the integral of induced currents for overcoming the limitations of the existing NURBS MOM-PO method. Grouping of the MOM region is utilised to enhance computational efficiency. Comparison of the results obtained from this method with that from MOM and existing NURBS MOM-PO shows that the present method is feasible. [ABSTRACT FROM AUTHOR]

Abstract: Chemical vapor transport (CVT) process with bromine as a transporting agent has been utilized for growing large-size MoSe2 single crystals by adding niobium dopant (nominal concentration ∼0.5%) during the growth process. The maximum-size crystals are about 10×10mm2 in surface area and 2mm in thickness. The large edge plane facilitates an easier study of the influence of crystal anisotropy on the electrical and optical properties of the layered crystals. Anisotropy of the conductivity and indirect band gap parallel and perpendicular to the crystal c-axis due to the interlayer van der Waals interaction and red shift of the indirect and direct band gaps due to doping have been measured. It is found that the electrical and optical properties of niobium-doped MoSe2 are almost similar to those of the pure MoSe2 single crystal apart from a drastic reduction in the conductivity anisotropy and red shift of the band gap. [Copyright &y& Elsevier]

In this paper we present the analysis of some structures with complex curved boundary in slot antenna and microstrip transmission lines by using the Parallel Modified Locally Conformal Finite Difference Time Domain (P-MLC-FDTD) Method. The Conformal FDTD technique developed by our group earlier was extended in the current analysis. To show the accuracy of the MPI-based parallelization MLC-FDTD method, several simulated results are given in the latter part of the paper and various comparisons are made for such a demonstration. [ABSTRACT FROM AUTHOR]

The goal of this research was to develop a systematic approach to quantify adsorption and biodegradation capacities on biological activated carbon (BAC). The role of adsorption and biodegradation on BAC was studied using a continuous column. Several media, i.e., granular activated carbon (GAC), seeded glass bead and seeded GAC, and a target compound (p-hydroxybenzoic acid) were selected. Before breakthrough, the effluent of the GAC column contained a small amount of p-hydroxybenzoic acid that contributed the greatest amount of organic carbon to the effluent of the glass bead column, which suggests that adsorption should be the prevailing mechanism for removal the p-hydroxybenzoic acid, and biodegradation should be responsible for reducing the ozonation intermediates. Also, the bioactivity approach (biomass respiration potential, BRP) of BAC can not only reveal the importance of biodegradation mechanisms for the intermediates of ozonation, but also quantify the extent of the adsorption or biodegradation reaction occurring on BAC. [ABSTRACT FROM AUTHOR]