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1.
禁忌搜索与固定变量结合的启发式算法求解UBQP   总被引:1,自引:0,他引:1  
提出了将固定变量与禁忌搜索结合的启发式算法来求解UBQP。此算法包含两个阶段:采用禁忌搜索得到一个参考解;根据该参考解固定或释放若干变量。选择固定变量还是释放变量由搜索的历史信息决定。此算法动态地在禁忌搜索与固定或释放变量这两个阶段之间交替进行,直到停机条件满足为止。用提出的算法对国际文献中公认的15个难算例进行实算测试,得到了全部测试算例的最优解。实验结果表明,该算法是求解UBQP的一个高效求解算法。  相似文献   

2.
平面选址问题的引力搜索算法求解   总被引:1,自引:0,他引:1  
为求解平面选址问题,给出了一种基于引力搜索算法的求解方法。算法利用万有引力定律进行全局搜索,采用一种邻域搜索方法进行局部搜索,实现算法全局优化和局部优化的平衡。通过大量实验和与现有求解方法的比较,结果验证了算法的可行性和有效性。  相似文献   

3.
可选时间窗VRP的禁忌搜索算法   总被引:1,自引:0,他引:1       下载免费PDF全文
车辆调度问题(VRP)是广泛应用于物流配送等领域的一类组合优化问题。对实际中广泛存在的可选时间窗的车辆调度问题(VRPATW)进行了研究,建立了VRPATW问题的数学模型,并利用PFIH算法和禁忌搜索的混合算法进行求解,最后通过实验说明此算法解决VRPATW问题的有效性和可行性。  相似文献   

4.
Probabilistic location problems are surveyed from the perspective of their use in the design of emergency service systems, with special emphasis on emergency medical systems. Pioneering probabilistic models were defined in the 1980s, as a natural extension of deterministic covering models (first generation models) and backup models (second generation). These probabilistic models, however, adopted simplifying assumptions that in many cases do not correspond to real-world situations, where servers usually cooperate and have specific individual workloads . Thus the idea of embedding the hypercube queueing model into these formulations is to make them more adherent to the real world. The hypercube model and its extensions are initially presented in some detail, which is followed by a brief review of exact and approximate methods for its solution. Probabilistic models for the design of emergency service systems are then reviewed. The pioneering models of Daskin and ReVelle and Hogan are extended by embedding the hypercube model into them. Solution methods for these models are surveyed next, with comments on specialized models for the design of emergency medical systems for urban areas and highways.  相似文献   

5.
The uncapacitated warehouse location problem (UWLP) has been studied by many researchers. It has been solved using various approaches, including branch and bound linear programming, tabu search, simulated annealing, and genetic algorithms. This study presents a new local search (LS) approach to the UWLP that is quite simple and robust and is efficient in some cases. The algorithm was tested against standard OR Library benchmarks and M* instances, which have already been used to test other approaches. The results show that the only disadvantage of the algorithm is the exponential growth of its computation time with the problem size. However, the multi-search design suggested here enables the algorithm to run under multi-processor or multi-core systems, which are currently provided as part of standard PC configurations.  相似文献   

6.
余鹏  隽志才 《计算机应用研究》2013,30(11):3232-3236
提出了用于描述两层应急抢修系统选址问题的0-1整数线性规划模型, 该模型能保证整个应急抢修系统的服务质量。设计了求解该问题的两种核搜索算法, 在两种方法中分别根据原问题的线性松弛和拉格朗日松弛确定原问题的核问题和子问题, 从而大大减小了问题的规模。用提出的算法对56个计算实例进行求解, 算例计算结果表明, 与MOSEK软件直接求解得到的结果进行比较, 基于拉格朗日松弛的核搜索算法可以在相对较短的时间内求得较好的解, 这说明拉格朗日松弛对偶问题的最优解能为求解原问题提供非常有效的信息。  相似文献   

7.
针对网络优化算法中的最短路径(Shortest Path,SP)问题,建立了有约束条件的SP问题模型,并探讨了使用禁忌搜索(Tabu Search,TS)算法对其求解的算法框架及关键步骤。该求解方法寻优能力强,结构简明,能方便处理问题约束,具有智能计算方法的优点。最后,通过实例进行测试和比较,证明算法收敛速度快,并能够获得满足约束条件的优解集合,能适应较差网络条件下的多条路径选择,算法是可行和有效的。  相似文献   

8.
针对一类配送中心选址问题,建立了问题的数学模型,将和谐搜索算法进行改进并对问题进行求解,最后将此算法与最优保存算法(EGA)和遗传算法(GA)进行比较,验证了算法在计算结果方面的精确性和计算时间上的高效性。  相似文献   

9.
纯粹的反应式导航算法在复杂未知环境下易陷入局部极小,为此提出一种基于局部子目标和禁忌搜索的自主导航算法.以当前可视区域内障碍物的关键角点为搜索邻域,利用禁忌搜索算法执行优化操作生成当前子目标,进而采用反应式导航算法对其进行跟踪,最终通过子目标的动态切换引导机器人驶达目标位置.算法可有效克服局部极小,显著提高机器人在复杂环境下的自主性.理论分析和仿真实验验证了算法的可行性和有效性.  相似文献   

10.
针对竞争选址问题,提出一种新的混合和声搜索算法。混合和声搜索算法初始化和声记忆库时结合了贪婪算法,降低了初始解的不可行性概率。在寻优过程中,引入了鱼群算法的觅食行为,提高了算法跳出局部最优解的能力和收敛速度。即兴产生一个新的和声时,充分考虑了当前最优解的指导作用,提出了新的基因调整方法,增强了算法的探索能力。在竞争选址问题上对所提出的算法进行了测试,仿真结果验证了所提出算法的有效性。  相似文献   

11.
The dynamic space allocation problem (DSAP) presented in this paper considers the task of assigning items (resources) to locations during a multi-period planning horizon such that the cost of rearranging the items is minimized. Three tabu search heuristics are presented for this problem. The first heuristic is a simple basic tabu search heuristic. The second heuristic adds diversification and intensification strategies to the first, and the third heuristic is a probabilistic tabu search heuristic. To test the performances of the heuristics, a set of test problems from the literature is used in the analysis. The results show that the tabu search heuristics are efficient techniques for solving the DSAP. More importantly, the proposed tabu search heuristic with diversification/intensification strategies found new best solutions using less computation time for one-half of all the test problems.  相似文献   

12.
An Algorithm Based on Tabu Search for Satisfiability Problem   总被引:3,自引:0,他引:3       下载免费PDF全文
In this paper,a computationally effective algorithm based on tabu search for solving the satisfiability problem(TSSAT)is proposed.Some novel and efficient heuristic strategies for generating candidate neighborhood of the curred assignment and selecting varibables to be flipped are presented. Especially,the aspiration criterion and tabu list tructure of TSSAT are different from those of traditional tabu search.Computational experiments on a class of problem insteances show that,TSSAT,in a reasonable amount of computer time ,yields better results than Novelty which is currently among the fastest known.Therefore TSSAT is feasible and effective.  相似文献   

13.
考虑设备应急抢修的时限要求和整个应急抢修系统的服务质量要求,采用0-1整数规划模型描述了应急抢修点选址问题,并针对该问题设计了一种混合遗传算法。在算法中使用启发式算法对种群中的不可行解进行修复,以保持种群在可行域内搜索,并采用近邻搜索算法改善种群中的最佳个体。算例计算的结果表明,该算法求得的结果要优于基于罚函数的遗传算法和采用简单修复算法的遗传算法。  相似文献   

14.
In the mobile facility location problem (MFLP), one seeks to relocate (or move) a set of existing facilities and assign clients to these facilities so that the sum of facility movement costs and the client travel costs (each to its assigned facility) is minimized. This paper studies formulations and develops local search heuristics for the MFLP. First, we develop an integer programming (IP) formulation for the MFLP by observing that for a given set of facility destinations the problem may be decomposed into two polynomially solvable subproblems. This IP formulation is quite compact in terms of the number of nonzero coefficients in the constraint matrix and the number of integer variables; and allows for the solution of large-scale MFLP instances. Using the decomposition observation, we propose two local search neighborhoods for the MFLP. We report on extensive computational tests of the new IP formulation and local search heuristics on a large range of instances. These tests demonstrate that the proposed formulation and local search heuristics significantly outperform the existing formulation and a previously developed local search heuristic for the problem.  相似文献   

15.
In this paper we present a novel grouping harmony search algorithm for the Access Node Location Problem (ANLP) with different types of concentrators. The ANLP is a NP-hard problem where a set of distributed terminals, with distinct rate demands, must be assigned to a variable number of concentrators subject to capacity constraints. We consider the possibility of choosing between different concentrator models is given in order to provide service demand at different cost. The ANLP is relevant in communication networks design, and has been considered before within the design of MPLS networks, for example. The approach we propose to tackle the ANLP problem consists of a hybrid Grouping Harmony Search (GHS) algorithm with a local search method and a technique for repairing unfeasible solutions. Moreover, the presented scheme also includes the adaptation of the GHS to a differential scheme, where each proposed harmony is obtained from the same harmony in the previous iteration. This differential scheme is perfectly adapted to the specifications of the ANLP problem, as it utilizes the grouping concept based on the proximity between nodes, instead of being only based on the grouping concept. This allows for a higher efficiency on the searching process of the algorithm. Extensive Monte Carlo simulations in synthetic instances show that this proposal provides faster convergence rate, less computational complexity and better statistical performance than alternative algorithms for the ANLP, such as grouping genetic algorithms, specially when the size of the scenario increases. We also include practical results for the application of GHS to a real wireless network deployment problem in Bizkaia, northern Spain.  相似文献   

16.
In this contribution, a parallel hybrid local search algorithm for the three‐dimensional container loading problem (CLP) is proposed. First a simulated annealing method for the CLP is developed, which is then combined with an existing tabu search algorithm to form a hybrid metaheuristic. Finally, parallel versions are introduced for these algorithms. The emphasis is on CLP instances with a weakly heterogeneous load. Numerical tests based on the well‐known 700 test instances from Bischoff and Ratcliff are performed, and the outcome is compared with methods from other authors. The results show a high solution quality obtained with reasonable computing time.  相似文献   

17.
This paper presents a novel parallel tabu search (PTS) algorithm equipped with a proper adaptive neighborhood generation mechanism to solve the primal buffer allocation problem, which consists of minimizing the total buffer capacity of a serial production system under a minimum throughput rate constraint. An evaluative method based on a specific algorithm has been implemented to simulate the system behavior. In order to validate the effectiveness of the proposed PTS a mixed integer linear programming-based simulation/optimization approach and several metaheuristics from the relevant literature have been implemented. Since most metaheuristics are sensitive to the parameter setting, a proper calibration analysis based on a non-parametric test has been performed. Then, a comprehensive comparison analysis, concerning with both quality of solutions and computational efficiency, has been carried out. Finally, through the numerical results obtained from PTS, a multi-factorial experimental analysis has been developed to analyze the influencing factors of the problem under investigation.  相似文献   

18.
针对最小化完工时间的作业车间调度问题(JSP),提出改进麻雀搜索算法(ISSA).首先设计有效的编码转换方式,形成JSP离散决策空间与麻雀搜索算法(SSA)连续搜索空间的对应关系.然后,针对SSA在求解后期易陷入局部最优,利用量子计算、正余弦搜索和警戒者数量递减策略对SSA进行改进,同时引入多邻域搜索和高斯扰动策略以弥补SSA在求解离散问题时深度发掘能力不足的弊端.最后,进行FT、LA系列10个测试问题、6种算法和2个应用实例的对比实验.结果表明,ISSA在求解JSP时,能获得更好的最小值、平均值和寻优成功率,验证了ISSA求解JSP的有效性.  相似文献   

19.
求解PDPTW 问题的一种快速禁忌搜索算法   总被引:7,自引:1,他引:7       下载免费PDF全文
提出一种解决实际规模和复杂度的PDPTW问题的快速禁忌搜索算法.该算法分为构造初始解和改进解两个阶段:在第1阶段,使用插入算法来构造一个尽可能好的初始解;在第2阶段,使用禁忌搜索算法来改进得到的解,最后构造了两个实际规模和复杂度的例子,测试结果表明该算法对于求解此类PDPTW问题是有效的。  相似文献   

20.
Abstract: In this paper we address the problem of locating a maximum weighted number of facilities such that no two are within a specified distance from each other. A natural process of evolution approach, more specifically a genetic algorithm, is proposed to solve this problem. It is shown that through the use of a commercially available spreadsheet-based genetic algorithm software package, the decision-maker with a fundamental knowledge of spreadsheets can easily set up and solve this optimization problem. Also, we report on our extensive computational experience using three different data sets.  相似文献   

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