基于文化算法和改进差分进化算法的混合算法

改进差分进化算法不能有效利用进化过程中的知识,传统文化算法进化后期收敛速度较慢。针对这些问题提出一种基于文化算法和改进差分进化算法的混合算法,并将这一算法应用于约束求解问题。对基准函数和丁烯烷化生产调度问题进行仿真,结果表明该混合算法具有较好的实用性和稳健性,在寻优效率和优化结果方面都优于与之比较的算法,并降低了计算量。     

多策略多参数并行差分进化算法

针对差分进化（DE）算法收敛早熟与计算效率不理想的问题,提出一种改进的差分进化算法。首先,在进化中同时并行多个策略与参数组合来提高个体多样性。其次,依据建立的评价指标自适应地调整组合来提高寻优效率。最后,把进化过程分为若干的子进程以避免前期优势组合不适应后期的问题。在10个标准测试函数上的实验结果表明,提出的算法与其他算法相比具有相对较好的性能。     

差异演化算法应用问题研究

差异演化算法作为一种较新的演化算法,具有全局搜索能力强、控制参数少、算法简单、容易实现等特点,但在具体应用中仍面临着演化模式如何选择及最佳种群大小如何取值等问题。本文利用典型的五类多变量函数对差异演化算法常用演化模式进行了比较测试研究,给出了演化模式选择建议;在同时考虑种群大小对差异演化算法优化效率及优化结果两方面影响的情况下,利用测试函数对最佳种群大小的取值进行了研究,给出了差异演化算法用于多变量函数优化时种群大小的适用取值范围。     

文化算法研究综述

文化算法模拟文化进化过程,在实现个体进化的种群空间基础上,构建信度空间,用于对进化过程中有效隐含信息的挖掘和利用。该双层进化机制为进化计算中的知识引导提供了通用框架,已证明能有效提高算法性能,并被成功用于解决诸多实际复杂优化问题。文章介绍了文化算法基本原理,从提取知识类型角度详细阐述了算法研究进展,总结了其在不同领域的应用,并展望了算法未来可能的研究方向。     

自适应调整控制参数的差异演化算法

控制参数选取是包括差异演化在内的演化算法设计时所面临的一个重要问题,对算法的性能有着重大影响.针对差异演化算法参数选取问题,提出一种利用个体适应度作为参数调整决策依据,并结合一定的调整概率对F和CR进行自适应调整的方法,解决了手工设置控制参数的不便.同时利用交叉操作生成双子代个体与父代个体竞争形成新一代种群,加快了算法的收敛.对标准测试函数的仿真实验结果表明,该算法无论在最优解质量和收敛速度上都优于相关算法,尤其对于高维函数而言.     

一种新型的差分演化算法及其应用研究

提出了一种新的基于简单多样性规则的改进差分演化算法,并把它运用于约束全局最优化问题的求解中。新算法的特征是: 1)提出一种新的混合自适应交叉变异算子,以增强算法的搜索能力; 2)采用具有保持群体多样性的约束函数处理技术; 3)简化基本差分演化算法的缩放因子,尽量减少算法的控制参数,方便工程人员的使用。通过对13个标准测试函数进行测试,并与其他演化算法结果进行比较。实验结果表明,新算法在求解精度和稳定性具有很好的性能,而且其函数平均评价次数要低于所比较的其他演化算法。     

差分进化算法参数控制与适应策略综述

差分进化算法逐渐成为进化计算领域最流行的随机搜索算法之一,已被成功用于求解各类应用问题.差分进化算法参数设置与其性能密切相关,因此算法参数控制与适应策略设计是目前该领域的研究热点之一,目前已涌现出大量参数控制方案,但尚缺乏系统性的综述与分析.首先简要介绍差分进化算法的基本原理与操作,然后将目前参数控制与适应策略分成基于经验的参数控制、参数随机化适应策略、基于统计学习的参数随机化适应策略和参数自适应策略4类进行系统性综述,重点介绍其中的参数适应与自适应策略.此外,为分析各种参数控制与适应策略的功效,以实值函数优化为问题背景设计了相关实验,进一步分析各种策略的效率与实用性,实验结果表明,参数自适应控制策略是目前该领域最有效的方法之一.     

差异演化算法及其改进形式的综述

差异演化算法是一种基于群体差异的演化算法,群体中每个向量代表问题的一个候选解,该算法利用向量之间的差异扰动整个种群,求解问题的最优解.综述了差异演化算法的基本原理、常用测试函数和算法优缺点,讨论了多种改进手段,如:三角变异、混沌理论、逆向计算、均匀设计表等,并给出了未来可能的研究方向.     

Improved differential evolution approach based on cultural algorithm and diversity measure applied to solve economic load dispatch problems

Evolutionary algorithms (EAs) are general-purpose stochastic search methods that use the metaphor of evolution as the key element in the design and implementation of computer-based problems solving systems. During the past two decades, EAs have attracted much attention and wide applications in a variety of fields, especially for optimization and design. EAs offer a number of advantages: robust and reliable performance, global search capability, little or no information requirement, and others. Among various EAs, differential evolution (DE), which characterized by the different mutation operator and competition strategy from the other EAs, has shown great promise in many numerical benchmark problems and real-world optimization applications. The potentialities of DE are its simple structure, easy use, convergence speed and robustness. To improve the global optimization property of DE, in this paper, a DE approach based on measure of population's diversity and cultural algorithm technique using normative and situational knowledge sources is proposed as alternative method to solving the economic load dispatch problems of thermal generators. The traditional and cultural DE approaches are validated for two test systems consisting of 13 and 40 thermal generators whose nonsmooth fuel cost function takes into account the valve-point loading effects. Simulation results indicate that performance of the cultural DE present best results when compared with previous optimization approaches in solving economic load dispatch problems.     

CMOS analogue amplifier circuits optimisation using hybrid backtracking search algorithm with differential evolution

This paper proposes a novel hybrid optimisation algorithm which combines the recently proposed evolutionary algorithm Backtracking Search Algorithm (BSA) with another widely accepted evolutionary algorithm, namely, Differential Evolution (DE). The proposed algorithm called BSA-DE is employed for the optimal designs of two commonly used analogue circuits, namely Complementary Metal Oxide Semiconductor (CMOS) differential amplifier circuit with current mirror load and CMOS two-stage operational amplifier (op-amp) circuit. BSA has a simple structure that is effective, fast and capable of solving multimodal problems. DE is a stochastic, population-based heuristic approach, having the capability to solve global optimisation problems. In this paper, the transistors’ sizes are optimised using the proposed BSA-DE to minimise the areas occupied by the circuits and to improve the performances of the circuits. The simulation results justify the superiority of BSA-DE in global convergence properties and fine tuning ability, and prove it to be a promising candidate for the optimal design of the analogue CMOS amplifier circuits. The simulation results obtained for both the amplifier circuits prove the effectiveness of the proposed BSA-DE-based approach over DE, harmony search (HS), artificial bee colony (ABC) and PSO in terms of convergence speed, design specifications and design parameters of the optimal design of the analogue CMOS amplifier circuits. It is shown that BSA-DE-based design technique for each amplifier circuit yields the least MOS transistor area, and each designed circuit is shown to have the best performance parameters such as gain, power dissipation, etc., as compared with those of other recently reported literature.     

基于两种进化模式的双种群协作差分演化算法

提出了一种基于两种进化模式的双种群协作差分演化算法（DPDE）。在DPDE中,两个种群通过协作共同进化。首先,各种群以不同的进化模式,通过个体竞争实现自身进化;其次,种群之间基于局部信息传递和共享机制,通过随机交换个体方式相互协作、共同进化,既实现了不同进化模式间的优势互补,又可以改善种群的多样性。对于5个典型Benchmark测试函数,通过与DE和DEfirDE算法的比较表明：DPDE具有更好的全局收敛性和鲁棒性,特别适合求解高维多模态函数的最优化问题。     

An improved differential evolution algorithm with fitness-based adaptation of the control parameters

Differential Evolution (DE) is arguably one of the most powerful stochastic real-parameter optimization algorithms of current interest. DE operates through the similar computational steps as employed by a standard Evolutionary Algorithm (EA). However, unlike the traditional EAs, the DE-variants perturb the current-generation population members with the scaled differences of randomly selected and distinct population members. Therefore, no separate probability distribution has to be used, which makes the scheme self-organizing in this respect. Scale Factor (F) and Crossover Rate (Cr) are two very important control parameters of DE since the former regulates the step-size taken while mutating a population member in DE and the latter controls the number of search variables inherited by an offspring from its parent during recombination. This article describes a very simple yet very much effective adaptation technique for tuning both F and Cr, on the run, without any user intervention. The adaptation strategy is based on the objective function value of individuals in the DE population. Comparison with the best-known and expensive variants of DE over fourteen well-known numerical benchmarks and one real-life engineering problem reflects the superiority of proposed parameter tuning scheme in terms of accuracy, convergence speed, and robustness.     

A differential evolution algorithm to solve redundancy allocation problems

To improve system reliability without changing its nature, three methods are proposed. The first method uses more reliable components and the second method provides redundant components within the system. The third method is a combination of these two methods. The redundancy allocation problem (RAP) finds the appropriate mix of components and redundancies within a system to maximize its reliability or minimize its cost due to several constraints, such as cost, weight, and volume. This paper presents a methodology to solve the RAP, which is an NP‐hard problem, modeled with discrete variables. In this paper, we use a metaheuristic to solve the RAP of a series–parallel system with a mix of components. Our metaheuristic offers a practical method with specific solution encoding, and combines a penalty function to solve large instances of the relaxed RAP, where different types of components can be used in parallel. The efficiency of the algorithm was tested through a set of well‐known benchmark problems from the literature. Testing of the algorithm achieved satisfactory results in reasonable computing time.     

基于模拟退火的混合差分演化算法研究

介绍了一种求解函数优化问题的新策略--差分演化算法,与其它算法相比,该算法具有稳健性强,收敛速度快的优点;同时,把模拟退火策略融入到差分演化的过程中,提出了一个混合演化算法--基于模拟退火的混合差分演化算法,实验表明混合后的算法比单一的差分演化算法更稳健,收敛速度也略有提高.     

基于差分进化的细菌觅食群游算法*

针对细菌觅食算法在优化过程中步长一致、速度较慢的缺陷,赋予细菌对环境感知的能力,并利用灵敏度的概念来调节群游步长,提高收敛速度;将差分进化的思想引入趋化算子,对趋化过程中的细菌位置进行修正,改善群游过程中部分维的退化现象,增加收敛的精度。采用高维典型测试函数对算法进行测试,新算法明显提高了搜索速度和精度,改造后适用于多维、约束等实际工程问题的优化。     

基于混沌搜索的自适应差分进化算法

提出一种基于混沌搜索的自适应差分进化算法（CADE）,该算法在计算过程中自适应地调整交叉率,在搜索初期保持种群多样性的同时增强算法的全局收敛性。具有较强局部遍历搜索性能的混沌搜索的引入使得算法具有较好的求解精度,增加搜索到全局最优解的概率。对几种典型的测试函数对CADE进行了测试,实验结果表明,该算法能有效地避免早熟收敛,具有良好的全局收敛性。     

一种求解高维多模态复杂问题的差分文化算法

针对在求解高维多峰值复杂问题时种群容易陷入局部搜索、求解精度低的问题,提出了一种基于自适应差分进化算法和小生境高斯分布估计的文化算法。将差分进化算法用于种群空间的优化,利用动态小生境识别算法在种群空间中识别小生境群体。信度空间利用高斯分布估计算法在小生境内进行局部优化,并将小生境特征存入进化知识库,进化知识库进一步引导种群空间,有效地保证了种群的多样性,避免了局部的重复搜索。最后,通过仿真实验测试表明,算法具有收敛速度快、求解精度高、稳定性高和全局搜索能力强等优势。     

参数适应性分布式差分进化算法

提出一种适应性分布式差分进化算法.将初始种群分为多个子种群,并设计子种群间的迁移机制,当满足迁移条件时,根据冯?诺依曼拓扑结构,子种群内的优秀个体代替其邻域的较差个体,使得整个种群实现信息共享.同时,根据个体适应值变化情况,对每一个体分配不同的缩放因子?和交叉率CR,提出?和CR的适应性策略.实验结果表明,所提出算法有利于对解空间进行广泛探索,避免算法陷入早熟收敛,能够搜索到性能较好的解.     

采用差分进化算法的点扩展函数估计

在图像处理的非盲复原算法中,对点扩散函数PSF（Point Spread Function）的估计是否准确,将直接影响图像复原质量的好坏。传统的估计方法有直接测量法和间接估计法,但往往数据量大,计算繁琐,针对这一问题,从全局寻优的角度出发,提出利用差分进化算法来估计点扩散函数。实验结果表明差分进化方法可以取得很好的效果,为下一步设计恢复滤波器奠定了基础。     

差异演化的实验研究

首先基于一些实例研究了差异演化(DE)的参数选择问题；然后在分析DE特点的基础上，将缩放因子F由固定数值设为随机函数，实现了一个简化的DE版本(SDE)，该方法不仅减少了需调整的参数，而且对CR的参数选择更为宽松．与已有文献中遗传算法的带约束型数值优化问题的实验结果对比，表明SDE能在较少的计算次数内获得较好的结果。