多变异策略的自适应差分演化算法

差分演化(Differential Evolution,DE)算法的性能依赖于变异策略的选择和控制参数的设置.不同问题对DE的变异策略和参数的设置各不相同.为了提高DE的性能,提出一种多变异策略的自适应差分演化算法,建立由多种变异策略组成的策略池,两个主要参数自适应策略控制.为了验证所提算法的性能,在测试数据集CEC2013上进行了实验,并将其与使用6种不同变异策略的原始DE和4种改进DE进行比较.实验结果表明,提出的算法是一种有效的DE变种,其性能优于其它DE.     

基于动态自适应策略的改进差分进化算法

针对差分进化算法处理复杂优化问题时存在后期收敛速度变慢、收敛精度不高和参数设置困难的问题,提出了一种基于动态自适应策略的改进差分进化算法(dn-DADE)。首先,新的变异策略DE/current-to-dnbest/1利用当前种群中的精英解引导有效的搜索方向来动态调整可选的精英解,使其在进化后期趋于全局最优解。其次,分别设计了缩放因子和交叉因子的自适应更新策略,使两者在搜索的不同阶段自适应变化,以弥补差分进化算法对参数敏感的不足,进一步提高算法的稳定性和鲁棒性。对14个benchmark函数进行了测试并与多种先进DE改进算法进行了比较,结果显示,dn-DADE算法具有较高的求解精度,收敛速度快,寻优性能显著。     

差分演化算法各种更新策略的对比分析

差分演化算法（differential evolution,DE）是一种模拟生物演化过程的随机搜索方法,具有收敛速度快,鲁棒性好等优点。目前DE有多种交叉和变异策略,它们在求解各类优化问题时表现出各自不同的性能。介绍了10种差分演化算法的更新策略,并利用标准测试函数集对它们进行了全面与系统的实验比较。通过分析采用这些策略的DE算法在不同解空间及进化各阶段的收敛曲线特点,对比总结了不同版本的DE算法在各类环境下的搜索性能。该研究一方面能够为DE算法的实际应用提供技术指导,帮助学者选择合适的DE更新策略以更好地解决工程问题;另一方面能够为新型DE更新策略的开发和自适应DE算法的设计提供理论基础。     

多模态函数优化的多种群进化策略

在一种使用单基因变异、精英繁殖、递减型策略参数的改进进化策略基础上,提出了一种求解多模态函数多个极值点的多种群协同进化策略,并给出了子种群进化概率、停止条件的确定和收敛到极值点的判断条件,在求多极值点的进化算法中,判别两个极值点是同峰还是异峰极值点是一个困难而关键的问题,为此引入了一种新的判别方法——山谷探索法,从而避免了确定小生境单径或峰半径,一组测试函数的仿真计算结果表明了所提出的算法能准确地找到全部极值点.     

进化策略在极大似然法参数估计中的应用

采用极大似然法进行参数估计,是为了避免传统优化算法的缺点。本文采用进化策略算法与极大似然参数估计法相结合使参数估计变量不再受初始值影响,从而可获得全局更优的解。最后,以威布尔三参数分布为例进行参数估计。结果表明,该方法有求解精度高和收敛速度快的优点,从而使进化策略算法能更好地应用于数理统计中。     

Evolution strategies for solving discrete optimization problems

A method to solve discrete optimization problems using evolution strategies (ESs) is described. The ESs imitate biological evolution in nature and have two characteristics that differ from other conventional optimization algorithms: (a) ESs use randomized operators instead of the usual deterministic ones; (b) instead of a single design point, the ESs work simultaneously with a population of design points in the space of variables. The important operators of ESs are mutation, selection and recombination. The ESs are commonly applied for continuous optimization problems. For the application to discrete problems, several modifications on the operators mutation and recombination are suggested here. Several examples from the literature are solved with this modified ES and the results compared. The examples show that the modified ES is robust and suitable for discrete optimization problems.     

一种低复杂度的基于进化策略的自适应运动估计方法

为了进一步提高编码质量并能快速编码,提出了一种新的基于进化策略的自适应运动估计算法。鉴于在进化策略中变异操作与正态分布法则对应,是核心算子,为此将进化策略应用于运动估计,提出了一种新的自适应运动估计算法,并第1次将运动方向信息作为变量引入运动估计算法,同时改进了步长自适应控制机制,以便进一步提高算法的收敛速率,同时采用种群规模的自适应控制,降低了算法的复杂度。试验结果表明,该算法的性能与全搜索算法相近,而复杂度略大于三步法。由于其具有低复杂度和进化算法的内在并行性的特点,故该算法适合硬件实现。     

Random Controlled Pool Base Differential Evolution Algorithm (RCPDE)

This paper presents a novel random controlled pool base differential evolution algorithm (RCPDE) where powerful mutation strategy and control parameter pools have been used. The mutation strategy pool contains mutations strategies having diverse parameter values, whereas the control parameter pool contains varying nature pairs of control parameter values. It has also been observed that with the addition of rarely used control parameter values in these pools are highly beneficial to enhance the performance of the DE algorithm. The proposed mutation strategy and control parameter pools improve the solution quality and the convergence speed of DE algorithm. The simulation results of the proposed RCPDE algorithm shows significant performance as compared to other algorithms when tested over a set of multi-dimensional benchmark functions.     

A New Approach for Predicting the Final Outcome of Evolution Strategy Optimization Under Noise

Differential-geometric methods are applied to derive steady state conditions for the (μ/μ _I ,λ)-ES on the general quadratic test function disturbed by fitness noise of constant strength. A new approach for estimating the expected final fitness deviation observed under such conditions is presented. The theoretical results obtained are compared with real ES runs, showing a surprisingly excellent agreement.     

Evolution strategies – A comprehensive introduction

This article gives a comprehensive introduction into one of the main branches of evolutionary computation – the evolution strategies (ES) the history of which dates back to the 1960s in Germany. Starting from a survey of history the philosophical background is explained in order to make understandable why ES are realized in the way they are. Basic ES algorithms and design principles for variation and selection operators as well as theoretical issues are presented, and future branches of ES research are discussed.