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1.
基于模矢搜索和遗传算法的混合约束优化算法   总被引:1,自引:0,他引:1  
近年,免梯度方法又开始引起大家的注意,由于不需要计算函数的梯度.特别适合用来求解那些无法得到梯度信息或需要花很大计算量才能得到梯度信息的问题.本文构造了一个基于模矢搜索和遗传算法的混合优化算法.在模矢搜索方法的搜索步,用一个类似于遗传算法的方法产生一个有限点集.算法是全局收敛的.  相似文献   

2.
一种改进的禁忌搜索算法及其在连续全局优化中的应用   总被引:1,自引:1,他引:1  
禁忌搜索算法是一种元启发式的全局优化算法,是局部搜索算法的一种推广,已被成功地应用于许多组合优化问题中。本文针对有界闭区域上的连续函数全局优化问题,提出了一种改进的禁忌搜索算法,并进行了理论分析和数值实验。数值实验表明,对于连续函数全局优化问题的求解该算法是可行有效的,并且结构简单,迭代次数较少,是一种较好的全局启发式优化算法。  相似文献   

3.
This paper presents a multiobjective search algorithm with subdivision technique (MOSAST) for the global solution of multiobjective constrained optimization problems with possibly noncontinuous objective or constraint functions. This method is based on a random search method and a new version of the Graef-Younes algorithm and it uses a subdivision technique. Numerical results are given for bicriterial test problems.  相似文献   

4.
刘淳安 《运筹与管理》2007,16(5):9-12,34
对非线性规划问题的处理通常采用罚函数法,使用罚函数法的困难在于参数的选取。本文提出了一种解非线性规划问题的新PSO算法(NSDPSO),该方法融入了一维搜索和动态调节技术,使NSDPSO很好地克服了标准PSO算法在前期收敛较快而在后期易陷入局部最优的缺陷。另外,文中还给出了一种新的适应度函数及选择算子,使算法在选择下一代时保持群体中不可行解的一定比例,这样不但能有效地增加群体的多样性,而且可以避免传统的过度惩罚,使群体向最优解逼近。最后的数据实验表明该算法对非线性规划问题求解是非常有效的。  相似文献   

5.
整数规划的布谷鸟算法   总被引:1,自引:0,他引:1  
布谷鸟搜索算法是一种新型的智能优化算法.本文采用截断取整的方法将基本布谷鸟搜索算法用于求解整数规划问题.通过对标准测试函数进行仿真实验并与粒子群算法进行比较,结果表明本文所提算法比粒子群算法拥有更好的性能和更强的全局寻优能力,可以作为一种实用方法用于求解整数规划问题.  相似文献   

6.
灰色非线性约束规划是灰色系统中一个重要的优化问题.为求解灰色非线性约束规划,给出了一种改进引力搜索算法的求解方法.实验结果表明改进引力搜索算法对求解灰色非线性约束规划可行有效.  相似文献   

7.
We suggested some modifications to the controlled random search (CRS) algorithm for global optimization. We introduce new trial point generation schemes in CRS, in particular, point generation schemes using linear interpolation and mutation. Central to our modifications is the probabilistic adaptation of point generation schemes within the CRS algorithm.A numerical study is carried out using a set of 50 test problems many of which are inspired by practical applications. Numerical experiments indicate that the resulting algorithms are considerably better than the previous versions. Thus, they offer a reasonable alternative to many currently available stochastic algorithms, especially for problems requiring direct search type methods.  相似文献   

8.
针对现有动态面板数据分析中存在偶发参数和没有考虑模型参数的不确定性风险问题,提出了基于Gibbs抽样算法的贝叶斯随机系数动态面板数据模型.假设初始值服从平稳分布,自回归系数服从Logit正态分布的条件下,设计了Markov链Monte Carlo数值计算程序,得到了模型参数的贝叶斯估计值.实证研究结果表明:基于Gibb...  相似文献   

9.
We propose a variant of the Nelder-Mead algorithm derived from a reinterpretation of univariate golden-section direct search. In the univariate case, convergence of the variant can be analyzed analogously to golden-section search. In the multivariate case, we modify the variant by replacing strict descent with fortified descent and maintaining the interior angles of the simplex bounded away from zero. Convergence of the modified variant can be analyzed by applying results for a fortified-descent simplicial search method. Some numerical experience with the variant is reported.  相似文献   

10.
Implementing Pure Adaptive Search with Grover's Quantum Algorithm   总被引:4,自引:0,他引:4  
Pure adaptive search (PAS) is an idealized stochastic algorithm for unconstrained global optimization. The number of PAS iterations required to solve a problem increases only linearly in the domain dimension. However, each iteration requires the generation of a random domain point uniformly distributed in the current improving region. If no regularity conditions are known to hold for the objective function, then this task requires a number of classical function evaluations varying inversely with the proportion of the domain constituted by the improving region, entirely counteracting the PAS apparent speedup. The Grover quantum computational search algorithm provides a way to generate the PAS iterates. We show that the resulting implementation, which we call the Grover adaptive search (GAS), realizes PAS for functions satisfying certain conditions, and we believe that, when quantum computers will be available, GAS will be a practical algorithm.  相似文献   

11.
We consider a generalization of the Weiszfeld algorithm with successive overrelaxation for data sets where some data point fields may be missing and prove its global convergence. A counterexample is also provided to the convergence of an alternative generalization.  相似文献   

12.
Based on Fermat’s principle and the automatic optimization mechanism in the propagation process of light,an optimal searching algorithm named light ray optimization is presented,where the laws of refraction and reflection of light rays are integrated into searching process of optimization.In this algorithm,coordinate space is assumed to be the space that is full of media with different refractivities,then the space is divided by grids,and finally the searching path is assumed to be the propagation path of light rays.With the law of refraction,the search direction is deflected to the direction that makes the value of objective function decrease.With the law of reflection,the search direction is changed,which makes the search continue when it cannot keep going with refraction.Only the function values of objective problems are used and there is no artificial rule in light ray optimization,so it is simple and easy to realize.Theoretical analysis and the results of numerical experiments show that the algorithm is feasible and effective.  相似文献   

13.
Global Optimization using Dynamic Search Trajectories   总被引:1,自引:0,他引:1  
Two global optimization algorithms are presented. Both algorithms attempt to minimize an unconstrained objective function through the modeling of dynamic search trajectories. The first, namely the Snyman–Fatti algorithm, originated in the 1980's and still appears an effective global optimization algorithm. The second algorithm is currently under development, and is denoted the modified bouncing ball algorithm. For both algorithms, the search trajectories are modified to increase the likelihood of convergence to a low local minimum. Numerical results illustrate the effectiveness of both algorithms.  相似文献   

14.
A novel staged continuous Tabu search (SCTS) algorithm is proposed for solving global optimization problems of multi-minima functions with multi-variables. The proposed method comprises three stages that are based on the continuous Tabu search (CTS) algorithm with different neighbor-search strategies, with each devoting to one task. The method searches for the global optimum thoroughly and efficiently over the space of solutions compared to a single process of CTS. The effectiveness of the proposed SCTS algorithm is evaluated using a set of benchmark multimodal functions whose global and local minima are known. The numerical test results obtained indicate that the proposed method is more efficient than an improved genetic algorithm published previously. The method is also applied to the optimization of fiber grating design for optical communication systems. Compared with two other well-known algorithms, namely, genetic algorithm (GA) and simulated annealing (SA), the proposed method performs better in the optimization of the fiber grating design.  相似文献   

15.
本文研究考虑交易成本的投资组合模型,分别以风险价值(VAR)和夏普比率(SR)作为投资组合的风险评价指标和效益评价指标。为有效求解此模型,本文在引力搜索和粒子群算法的基础上提出了一种混合优化算法(IN-GSA-PSO),将粒子群算法的群体最佳位置和个体最佳位置与引力搜索算法的加速度算子有机结合,使混合优化算法充分发挥单一算法的开采能力和探索能力。通过对算法相关参数的合理设置,算法能够达到全局搜索和局部搜索的平衡,快速收敛到模型的最优解。本文选取上证50股2014年下半年126个交易日的数据,运用Matlab软件进行仿真实验,实验结果显示,考虑交易成本的投资组合模型可使投资者得到更高的收益率。研究同时表明,基于PSO和GSA的混合算法在求解投资组合模型时比单一算法具有更好的性能,能够得到满意的优化结果。  相似文献   

16.
Grover’s quantum algorithm promises a quadratic acceleration for any problem formulable as a search. For unstructured search problems, its implementation and performance are well understood. The curse of dimensionality and the intractability of the general global optimization problem require any identifiable structure or regularity to be incorporated into a solution method. This paper addresses the application of Grover’s algorithm when a local search technique is available, thereby combining the quadratic acceleration with the acceleration seen in the multistart method. The author thanks Dr. Bill Baritompa for helpful discussions.  相似文献   

17.
We propose a new inexact line search rule and analyze the global convergence and convergence rate of related descent methods. The new line search rule is similar to the Armijo line-search rule and contains it as a special case. We can choose a larger stepsize in each line-search procedure and maintain the global convergence of related line-search methods. This idea can make us design new line-search methods in some wider sense. In some special cases, the new descent method can reduce to the Barzilai and Borewein method. Numerical results show that the new line-search methods are efficient for solving unconstrained optimization problems. The work was supported by NSF of China Grant 10171054, Postdoctoral Fund of China, and K. C. Wong Postdoctoral Fund of CAS Grant 6765700. The authors thank the anonymous referees for constructive comments and suggestions that greatly improved the paper.  相似文献   

18.
提出了一种带服务优先级车辆路径问题的模型(Vehicle Routing Problem with Precedence Constraints,VRPPC),和一种扫描—禁忌搜索算法(sweep-Taboo Search Algorithm,S-TSA).然后,运用S-TSA对郑煤物资供销有限公司的带有服务优先级的危险物资配送进行优化求解,并与扫描遗传算法(sweep-Genetic Algorithm,SGA),禁忌搜索算法(Taboo Search Algorithm,TSA),人工鱼群算法(Artificial Fish Algorithm,AFA)进行比较研究,研究结果显示:扫描禁忌搜索算法能在满足服务优先级的前提下,使配送费用最少.  相似文献   

19.
Presented in this paper is the prototype of a very general algorithm referred to as Division – Deletion Algorithm (DDA) for solving the most general global search problem. Various necessary conditions, sufficient conditions, and necessary and sufficient conditions for the convergence of the algorithm are proposed and analyzed. As an example of its application, we demonstrate that the convergence of a standard Hansen’s interval algorithm for unconstrained global optimization simply follows from this general theory.  相似文献   

20.
This paper describes several massively parallel implementations for a global search algorithm DIRECT. Two parallel schemes take different approaches to address DIRECT’s design challenges imposed by memory requirements and data dependency. Three design aspects in topology, data structures, and task allocation are compared in detail. The goal is to analytically investigate the strengths and weaknesses of these parallel schemes, identify several key sources of inefficiency, and experimentally evaluate a number of improvements in the latest parallel DIRECT implementation. The performance studies demonstrate improved data structure efficiency and load balancing on a 2200 processor cluster.  相似文献   

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