一种基于量子进化算法的概率进化算法

针对量子进化算法(QEA)求解二进制编码问题比较有效,而求解多进制编码问题则比较困难,提出一种概率进化算法(PEA)。该算法汲取了量子复合位、叠加态等思想,采用由观测概率构成的概率复合位进行编码,观测和更新操作直接针对观测概率进行。PEA保持了QEA的性能,运算速度远优于QEA,并可以采用任意进制编码。函数优化和背包问题实验验证了PEA的有效性。     

一种新的相位角编码量子进化算法

针对具有连续解空间的数值函数优化问题,基于量子算法和实数编码进化算法的思想,提出一种新的相位角编码量子进化算法(PAQEA).算法的概率表达特性使得量子染色体能够以一定概率表达优化问题的所有可行解,结合动态量子旋转门实现染色体的进化,实现了算法局部搜索与全局搜索的平衡.理论分析证明了算法的全局收敛性.仿真结果表明,该算法适用于复杂数值函数优化问题,具有收敛速度快、搜索能力强和稳定性高的特点.     

基于混合量子进化计算的混沌系统参数估计

混沌系统参数估计本质上是一多维参数优化问题.为精确估计混沌系统的未知参数,本文提出一种混合量子进化算法(HQEA)用于求解该优化问题,该方法采用实数量子角形式表示染色体,用量子比特的概率作为个体的当前位置信息;提出由差分进化计算更新量子位置状态的量子差分进化算法(QDE),并将其与实数编码量子进化算法(RQEA)相融合,以便令算法在解空间的全局探索和局部开发能力之间取得平衡.算法还引入量子非门算子,对当前最佳个体中按某个概率选中的量子比特位,进行变换操作,以便增强算法跳出局部最优解的能力.基准函数测试表明混合算法的全局搜索能力及可靠性都有很大改善.通过Lorenz混沌系统进行数值仿真,结果表明了该混合算法的有效性.     

多进制概率角复合位编码量子进化算法

针对量子进化算法求解二进制编码问题比较有效,而求解多进制编码问题则比较困难的情况,本文提出了一种多进制概率角复合位编码量子进化算法.该算法将量子进化算法中量子位的概率幅表示法转化为复合位的概率角表示法,采用随机观测方法得到观测个体,采用概率角增减对个体进行更新.该算法适用于采用任意进制编码的问题.实验表明,与量子进化算法和传统遗传算法相比,多进制概率角复合位编码量子进化算法在适用范围、搜索能力和运算速度上具有较明显优势.     

混合量子进化算法及其应用

文章将量子进化算法(QEA)和粒子群算法(PSO)互相结合,提出了两种混合量子进化算法。第一种算法叫做嵌入式粒子群量子进化算法,其主要思想是将简化的PSO进化方程嵌入QEA的进化操作中,简化了QEA算法的结构,增强了QEA跳出局部极值的能力。第二种算法叫做量子二进制粒子群算法,其主要思想是将QEA中的量子染色体的概念引入二进制粒子群算法(BPSO),提高了BPSO算法保持种群多样性的能力和运算速度。通过对0-1背包问题和多用户检测问题的求解表明,新的算法不仅操作更简单,而且全局搜索能力有了显著的提高。     

实数编码量子进化算法

为求解复杂函数优化问题,基于量子计算的相关概念和原理,提出一种实数编码量子进化算法.首先构造了由自变量向量的一个分量和量子比特的一对概率幅为等位基因的三倍体染色体,增加了解的多样性;然后利用量子旋转门和依据量子比特概率幅满足归一化条件设计的互补双变异算子进化染色体,实现局部搜索和全局搜索的平衡.标准函数仿真表明,该算法适合求解复杂函数优化问题,具有收敛速度快、全局搜索能力强和稳定性好的优点.     

一种基于细菌趋药行为的量子算法

菌群觅食优化算法具有算法简单、鲁棒性强和具备全局搜索能力的特点。但该算法收敛速度慢,对于多峰函数容易陷入局部最优。为提高菌群优化算法的搜索能力,避免其陷入早熟收敛,提出一种量子菌群算法,将二进制编码的量子进化算法融合到菌群算法中,用量子染色体表示细菌,用量子旋转门实现细菌状态更新。通过标准测试函数对其优化性能进行研究,实验结果表明,该算法无论是对于普通函数还是多峰函数,在收敛速度、收敛稳定性和寻找全局最优方面均优于菌群算法和量子遗传算法。     

基于自适应机制的多宇宙并行量子衍生进化算法

进化参量的选取对量子衍生进化算法(QEA)的优化性能有极大的影响,传统QEA在选择进化参量时并未考虑种群中个体间的差异,种群中所有个体采用相同的进化参量完成更新,导致算法在解决组合优化问题中存在收敛速度慢、容易陷入局部最优解等问题。针对这一问题,采用自适应机制调整QEA的旋转角步长和量子变异概率,算法中任意一代的任一个体的进化参量均由该个体自身适应度确定,从而保证尽可能多的进化个体能够朝着最优解方向不断靠近。此外,由于自适应量子进化算法需要评估个体的适应度,导致运算时间较长,针对这一问题则采用多宇宙机制将算法分布于多个宇宙中并行实现,从而提高算法的执行效率。通过搜索多峰函数最优解和求解背包问题测试算法性能,结果表明,与传统QEA相比,所提出算法在收敛速度、搜索全局最优解及执行速度方面具有较好的表现。     

改进的耗散量子粒子群优化算法及其应用*

针对量子粒子群优化算法(QPSO)存在着保持种群多样性差、容易陷入局部最优等缺陷,将耗散操作算子引入到QPSO量子角度更新中,提出了改进的耗散量子粒子群优化算法(DQPSO)。为验证算法的有效性,将DQPSO算法应用于标准函数优化问题。仿真结果表明,改进的耗散量子粒子群算法的优化性能优于传统的量子进化算法(QEA)和QPSO算法。可见,在量子角度更新策略中引入耗散操作算子能够使算法更好地保持种群的多样性、摆脱局部最优的限制、提高算法的搜索能力。     

混合量子算法及其在flow shop问题中的应用

量子进化算法（QEA）是目前较为独特的优化算法,它的理论基础是量子计算。算法充分借鉴了量子比特的干涉性、并行性,使得QEA求解组合优化问题具备了可行性。由于在求解排序问题中,算法本身存在收敛慢,没有利用其它未成熟个体等缺陷,将微粒群算法（PSO）及进化计算思想融入QEA中,构成了混合量子算法（HQA）。采用flow shop经典问题对算法进行了测试,结果证明混合算法克服了QEA的缺陷,对于求解排序问题具有一定的普适性。     

一种改进的量子进化算法及其在乡村邮路问题的应用

针对基本量子进化算法易陷于局部最优解的缺陷,提出一种改进的量子进化算法(QEA)。结合乡村邮路问题,对算法进行了测试,结果表明,改进算法在全局寻优能力和种群多样性方面比基本量子进化算法有所改进,是求解乡村邮路问题的一种有效算法。     

采用灰色码观测的量子进化算法

针对传统量子进化算法采用二进制观测机制,导致量子波动幅度较大且连续观测到相邻实数概率低的问题,本文提出了一种采用灰色码观测机制的量子进化算法.由于量子擅长全局搜索,灰色码擅长局部搜索,因此所提出的算法能较好平衡勘探和开采能力,量子进化更加平滑和高效.通过实验表明,算法能有效避免早熟和局部极值等问题,算法的精度更高,收敛速度更快.     

Solving the traveling salesman problem using cooperative genetic ant systems

The travelling salesman problem (TSP) is a classic problem of combinatorial optimization and has applications in planning, scheduling, and searching in many scientific and engineering fields. Ant colony optimization (ACO) has been successfully used to solve TSPs and many associated applications in the last two decades. However, ACO has problem in regularly reaching the global optimal solutions for TSPs due to enormity of the search space and numerous local optima within the space. In this paper, we propose a new hybrid algorithm, cooperative genetic ant system (CGAS) to deal with this problem. Unlike other previous studies that regarded GA as a sequential part of the whole searching process and only used the result from GA as the input to subsequent ACO iterations, this new approach combines both GA and ACO together in a cooperative manner to improve the performance of ACO for solving TSPs. The mutual information exchange between ACO and GA in the end of the current iteration ensures the selection of the best solutions for next iteration. This cooperative approach creates a better chance in reaching the global optimal solution because independent running of GA maintains a high level of diversity in next generation of solutions. Compared with results from other GA/ACO algorithms, our simulation shows that CGAS has superior performance over other GA and ACO algorithms for solving TSPs in terms of capability and consistency of achieving the global optimal solution, and quality of average optimal solutions, particularly for small TSPs.     

一种混合的离散细菌菌落优化算法

为了利用细菌算法解决组合优化问题, 提出了一种混合的离散细菌菌落优化算法。根据现有细菌优化算法, 设计一种新的个体编码方式及进化模式, 通过设计种群的自适应调整因子增强个体活力, 并融合禁忌搜索算法, 克服算法易于陷入过早收敛的不足, 并与其他算法在Taillard标准调度测试问题集上比较实验, 验证了算法的有效性。仿真结果表明, 该算法可以搜索到问题的最优组合, 能够有效避免算法陷入局部最优, 取得了满意的结果。     

A hybrid shuffled complex evolution approach with pattern search for unconstrained optimization

The difficulties associated with using classical mathematical programming methods on complex optimization problems have contributed to the development of alternative and efficient numerical approaches. Recently, to overcome the limitations of classical optimization methods, researchers have proposed a wide variety of meta-heuristics for searching near-optimum solutions to problems. Among the existing meta-heuristic algorithms, a relatively new optimization paradigm is the Shuffled Complex Evolution at the University of Arizona (SCE-UA) which is a global optimization strategy that combines concepts of the competition evolution theory, downhill simplex procedure of Nelder-Mead, controlled random search and complex shuffling. In an attempt to reduce processing time and improve the quality of solutions, particularly to avoid being trapped in local optima, in this paper is proposed a hybrid SCE-UA approach. The proposed hybrid algorithm is the combination of SCE-UA (without Nelder-Mead downhill simplex procedure) and a pattern search approach, called SCE-PS, for unconstrained optimization. Pattern search methods are derivative-free, meaning that they do not use explicit or approximate derivatives. Moreover, pattern search algorithms are direct search methods well suitable for the global optimization of highly nonlinear, multiparameter, and multimodal objective functions. The proposed SCE-PS method is tested with six benchmark optimization problems. Simulation results show that the proposed SCE-PS improves the searching performance when compared with the classical SCE-UA and a genetic algorithm with floating-point representation for all the tested problems. As evidenced by the performance indices based on the mean performance of objective function in 30 runs and mean of computational time, the SCE-PS algorithm has demonstrated to be effective and efficient at locating best-practice optimal solutions for unconstrained optimization.     

Various hybrid methods based on genetic algorithm with fuzzy logic controller

In this paper we propose several efficient hybrid methods based on genetic algorithms and fuzzy logic. The proposed hybridization methods combine a rough search technique, a fuzzy logic controller, and a local search technique. The rough search technique is used to initialize the population of the genetic algorithm (GA), its strategy is to make large jumps in the search space in order to avoid being trapped in local optima. The fuzzy logic controller is applied to dynamically regulate the fine-tuning structure of the genetic algorithm parameters (crossover ratio and mutation ratio). The local search technique is applied to find a better solution in the convergence region after the GA loop or within the GA loop. Five algorithms including one plain GA and four hybrid GAs along with some conventional heuristics are applied to three complex optimization problems. The results are analyzed and the best hybrid algorithm is recommended.     

An effective hybrid discrete differential evolution algorithm for the flow shop scheduling with intermediate buffers

In this paper, an effective hybrid discrete differential evolution (HDDE) algorithm is proposed to minimize the maximum completion time (makespan) for a flow shop scheduling problem with intermediate buffers located between two consecutive machines. Different from traditional differential evolution algorithms, the proposed HDDE algorithm adopted job permutation to represent individuals and applies job-permutation-based mutation and crossover operations to generate new candidate solutions. Moreover, a one-to-one selection scheme with probabilistic jumping is used to determine whether the candidates will become members of the target population in next generation. In addition, an efficient local search algorithm based on both insert and swap neighborhood structures is presented and embedded in the HDDE algorithm to enhance the algorithm’s local searching ability. Computational simulations and comparisons based on the well-known benchmark instances are provided. It shows that the proposed HDDE algorithm is not only capable to generate better results than the existing hybrid genetic algorithm and hybrid particle swarm optimization algorithm, but outperforms two recently proposed discrete differential evolution (DDE) algorithms as well. Especially, the HDDE algorithm is able to achieve excellent results for large-scale problems with up to 500 jobs and 20 machines.     

一种求解邮路问题的量子进化算法

乡村邮递员问题属于NP完全问题,对它的近似求解方法主要是智能算法及线性规划,但其中的基本量子进化算法易陷于局部最优解。为此,提出一种新的量子进化算法,结合城市垃圾运输问题,对算法进行测试。结果表明,该算法在全局寻优能力及种群多样性方面均比传统算法有所改进,是求解乡村邮递员问题的一种有效算法。     

双群体伪并行差分进化算法研究及应用

为了提高差分进化算法的全局搜索能力和收敛速率,本文提出了一种双群体伪并行差分进化算法.该算法结合差分进化算法DE/best/2/bin变异方式局部搜索能力强、收敛速度快,和DE/rand/1/bin变异方式全局搜索能力强、鲁棒性好的特点,采用串行算法结构实现并行差分进化算法独立进化、信息交换的思想.为使初始化个体均匀分布在搜索空间,提高算法收敛到全局最优解的鲁棒性,提出了一种基于平均熵的初始化策略.典型Benchmarks函数测试和非线性系统模型参数估计结果表明,该方法能显著提高算法的收敛速率和全局搜索能力.     

聚类问题的自适应杂交差分演化模拟退火算法

针对K-均值聚类算法对初始值敏感和易陷入局部最优的缺点,提出了一个基于自适应杂交差分演化模拟退火的K-均值聚类算法。该算法以差分演化算法为基础,通过模拟退火算法的更新策略来增强全局搜索能力,并运用自适应技术来选择学习策略、确定算法的关键参数。实验结果表明,该算法能较好地克服传统K-均值聚类算法的缺点,具有较好的全局收敛能力,且算法稳定性强、收敛速度快,将新算法与传统的K-均值聚类算法以及最近提出的几个同类聚类算法进行了比较。