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Abstract: In this paper, a new auxiliary function with one parameter on box constrained for escaping the current local minimizer of global optimization problem is proposed. First, a new definition of the filled function for box constrained minimization problem is given and under mild assumptions, this new auxiliary function is really a filled function. Then a new solution algorithm is proposed according to the theoretical analysis. And some numerical results demonstrate the efficiency of this method for box constrained global optimization. [Copyright &y& Elsevier]

Abstract: An improved particle swarm optimization (IPSO) is proposed in this paper. In the new algorithm, a population of points sampled randomly from the feasible space. Then the population is partitioned into several sub-swarms, each of which is made to evolve based on particle swarm optimization (PSO) algorithm. At periodic stages in the evolution, the entire population is shuffled, and then points are reassigned to sub-swarms to ensure information sharing. This method greatly elevates the ability of exploration and exploitation. Simulations for three benchmark test functions show that IPSO possesses better ability to find the global optimum than that of the standard PSO algorithm. Compared with PSO, IPSO is also applied to identify the hydrologic model. The results show that IPSO remarkably improves the calculation accuracy and is an effective global optimization to calibrate hydrologic model. [Copyright &y& Elsevier]

Abstract: In this paper, we study the positive almost periodic solutions for a class of almost periodic Lotka-Volterra type system with delays and feedback controls. Applying Schauder’s fixed point theorem, a criterion on the existence of the positive almost periodic solution of the system is obtained. Our new criterion, which improves and generalizes some well known results, can be easily checked. [Copyright &y& Elsevier]

Abstract: During the past decade, hybrid algorithms combining evolutionary computation and constraint-handling techniques have shown to be effective to solve constrained optimization problems. For constrained optimization, the penalty function method has been regarded as one of the most popular constraint-handling technique so far, whereas its drawback lies in the determination of suitable penalty factors, which greatly weakens the efficiency of the method. As a novel population-based algorithm, particle swarm optimization (PSO) has gained wide applications in a variety of fields, especially for unconstrained optimization problems. In this paper, a hybrid PSO (HPSO) with a feasibility-based rule is proposed to solve constrained optimization problems. In contrast to the penalty function method, the rule requires no additional parameters and can guide the swarm to the feasible region quickly. In addition, to avoid the premature convergence, simulated annealing (SA) is applied to the best solution of the swarm to help the algorithm escape from local optima. Simulation and comparisons based on several well-studied benchmarks demonstrate the effectiveness, efficiency and robustness of the proposed HPSO. Moreover, the effects of several crucial parameters on the performance of the HPSO are studied as well. [Copyright &y& Elsevier]

Abstract: The optimal design of digital systems can be complicated by non-linearities that arise from discrete optimization processes, and conventional methods often attain suboptimal results. Quantum computing may be an interesting technology to overcome that issue, but so far its effectiveness has been addressed from a most abstract perspective. This paper tackles the digital-design problem from a practical viewpoint, and derives universal criteria for assessing whether, and how much, quantum technologies can improve over conventional methods: the advantage is expressed in terms of computing time required to attain optimal design. The general framework is applied to two modern problems, i.e., training support vector machines and building vector quantizers. The experimental comparison between conventional and quantum methods addresses the actual performances of the designed systems in the case of vector quantization. Empirical evidence matches theoretical expectations and supports the design method’s consistency. [Copyright &y& Elsevier]

Abstract: In this paper, we consider the delayed periodic logistic equationwhich describes the evolution of a single species. Sufficient conditions which guarantee the permanence and the globally attractivity of the system are obtained. [Copyright &y& Elsevier]

Abstract: In this paper, the one-dimensional nonlinear Burgers’ equation is solved by using the Adomian decomposition method (ADM). We prove the convergence of this method applied to the nonlinear Burgers’ equation. The approximate solution of this equation is calculated in the form of a series with easily computable components. The accuracy of the proposed numerical scheme is examined by comparison with other analytical and numerical results. In addition, the numerical results shows that our present method is more easy and accurate than other methods. The method performs well. [Copyright &y& Elsevier]