约束动态免疫算法及对背包问题性能测试研究

借鉴人工免疫系统的记忆、动态识别等功能,提出一种约束动态免疫算法(CDIOA),并用于高维约束动态背包问题的求解。通过随机约束选择策略选择可行及非可行抗体,非可行抗体参与群体的进化;利用抗体修正策略确保进化群中有一定比例可行抗体,提高算法搜索功能;设计环境识别模块判断环境变化与否,建立环境记忆池保存较优秀记忆细胞,记忆细胞参与相似(相同)环境初始群的产生,加速算法在相似环境搜索速度。建立三种不同环境的动态背包问题作为标准测试实例,将CDIOA与已有的四种动态优化算法进行测试比较,结果表明:CDIOA对各测试问题在不同环境表现出较好的收敛性能,在相似环境能快速跟踪最优值。     

动态环境下的种群扩散粒子群优化算法

传统的粒子群优化算法在优化过程中难以有效地监测环境的动态变化和响应。针对上述问题,通过增加外围监测粒子加强监测有效性,提出一种可以动态响应环境变化的种群多样性扩散函数,在此基础上设计一种扩散粒子群优化算法(DPSO),在动态环境中与APSO、CPSO进行比较,实验结果表明,DPSO可以更有效地跟踪动态环境下极值的变化并快速收敛。     

多目标约束优化免疫算法研究及其应用

基于生物免疫中抗体应答抗原的机理,提出具有动态性能的多目标约束优化算法,解决一般性的多目标约束最优化问题.该算法的关键在于如何充分模拟免疫应答的机制构建算子模块,以及如何提出约束条件处理和聚类新方法有效解决优化问题.其特点是稳健性及记忆细胞集保存优良抗体并用聚类算法限制其规模,抗体群规模动态调节及抗体应答的对象是抗原群,群体具有自我调节多样性和自适应环境的能力且能并行处理复杂优化问题.仿真事例比较验证该文算法的有效性及能处理高维优化问题.     

基于模拟退火选择的动态免疫算法及其应用

借鉴人工免疫系统的记忆、动态识别等功能及模拟退火选择理论,提出一种适用于求解动态环境优化问题的动态免疫算法(DIASA),并将其用于高维动态约束背包问题。算法设计包括:(1)抗体的亲和力随群体进化而变化;(2)可行抗体被克隆和动态突变,突变概率与抗体浓度相关,而非可行抗体按价值密度贪婪修正;(3)新环境初始群经环境识别算子按不同方式生成,相似环境初始群由记忆细胞及随机抗体产生。数值实验中,选取著名的动态进化算法(ETGA)和动态免疫遗传算法(ISGA),通过不同难度的高维动态约束背包问题进行仿真比较,结果表明:DIASA较算法ISGA和ETGA对不同问题在各环境内表现较强的优化性能,群体中抗体多样性保持较好,能快速跟踪不同环境的最优值,收敛性强。     

改进的免疫优化算法对动态约束多目标问题的应用

基于进化理论的动态多目标优化算法极易陷入局部最优,跟踪动态Pareto有效面的速度及效果较差。基于免疫系统机理提出一种改进的免疫优化算法(DMIOA)用于动态约束多目标问题求解。算法通过抗体浓度及其支配度设计抗体与抗原亲和力,随机约束选择算子提高算法约束处理能力,环境识别算子自适应判断环境变化,根据识别结果以不同的方式产生新环境的初始抗体群。数值实验中,将DMIOA应用于两种动态标准测试问题及飞机减速器参数动态设计问题的求解,结果表明:DMIOA能快速跟踪动态Pareto有效面,且在各环境所获面分布均匀,具有较好的实际问题求解能力。     

动态免疫优化算法及其在背包问题中的应用

利用人工免疫系统的学习、记忆、识别等功能,提出一种动态免疫优化算法(DIOA),用于解决一类高维动态约束优化问题.其中对可行抗体进行克隆突变操作,非可行抗体按价值密度使用贪婪算法进行修正,环境识别模块借助记忆细胞产生新的环境初始群,从而加快算法收敛速度.利用DIOA求解不同环境下的高维背包问题,结果表明,与同类算法相比...     

动态评价粒子群优化及风电场微观选址

提出了动态评价方法处理一类约束优化问题.将目标函数值和约束违反量进行动态归一化处理,再进行加权求和,动态评价解的优化性能.不仅解决了惩罚因子确定困难的问题,而且增加了优化算法的多样性,提高了优化算法搜索全局最优解的能力.将动态评价方法引入粒子群算法,求解风电场微观选址优化问题.仿真结果表明,动态评价方法提高了风电场发电量和风能利用效率.此外,该方法可广泛应用于其他优化算法以求解约束优化问题.     

基于NN改进PSO算法的机器人路径规划

本文介绍了基于神经网络和微粒群优化算法的移动机器人动态避障路径规划算法.通过神经网络改进的微粒群算法,充分利用了神经网络的融合性和并行性来提高微粒群算法中适应度函数的准确性.通过神经网络描述机器人工作空间的动态环境约束并找到最优的适应度函数,在微粒群算法中使用该函数,求得微粒群算法最优无碰路径.     

一种求解动态背包问题的离散粒子群优化算法

动态背包问题(DKP)是一类经典的动态优化问题,可以用来描述许多实际的问题。迄今为止,针对动态背包问题的研究主要集中在遗传算法上,而对粒子群优化算法的研究较少。在离散粒子群优化模型的基础上,引入环境变化的探测以及环境变化后的响应机制,提出一种求解动态背包问题的离散粒子群优化算法(DSDPSO)。将该算法和现有经典的自适应原对偶遗传算法(APDGA)在两个动态背包问题上进行了对比实验,结果表明,DSDPSO算法在环境变化后能迅速地找到最优解并稳定下来,更适合于求解动态背包问题。     

动态离散粒子群优化算法

为解决现实世界中动态环境下的离散事件优化问题,研究了当前已被广泛应用于动态环境或离散运算优化问题的粒子群优化算法(PSO),据此提出了一种动态离散PSO算法.该算法设计了一种环境绝对值和环境敏感性判定策略来实现动态环境的监测与响应,并通过带变异算子的离散PSO算法公式的重新定义来满足大规模离散运算需求.最后,利用离散时间系统的零状态响应求解评价了该算法的性能,结果表明,该算法在定义域内具有较好的收敛性.     

一类带约束动态多目标优化问题的进化算法

动态多目标约束优化问题是一类NP-Hard问题,定义了动态环境下进化种群中个体的序值和个体的约束度,结合这两个定义给出了一种选择算子.在一种环境变化判断算子下给出了求解环境变量取值于正整数集Z+的一类带约束动态多目标优化问题的进化算法.通过几个典型的Benchmark函数对算法的性能进行了测试,其结果表明新算法能够较好地求出带约束动态多目标优化问题在不同环境下质量较好、分布较均匀的Pareto最优解集.     

Danger theory based artificial immune system solving dynamic constrained single-objective optimization

In this paper, we propose an artificial immune system (AIS) based on the danger theory in immunology for solving dynamic nonlinear constrained single-objective optimization problems with time-dependent design spaces. Such proposed AIS executes orderly three modules—danger detection, immune evolution and memory update. The first module identifies whether there are changes in the optimization environment and decides the environmental level, which helps for creating the initial population in the environment and promoting the process of solution search. The second module runs a loop of optimization, in which three sub-populations each with a dynamic size seek simultaneously the location of the optimal solution along different directions through co-evolution. The last module stores and updates the memory cells which help the first module decide the environmental level. This optimization system is an on-line and adaptive one with the characteristics of simplicity, modularization and co-evolution. The numerical experiments and the results acquired by the nonparametric statistic procedures, based on 22 benchmark problems and an engineering problem, show that the proposed approach performs globally well over the compared algorithms and is of potential use for many kinds of dynamic optimization problems.     

一类动态非线性约束优化问题的新解法

动态非线性约束优化是一类复杂的动态优化问题,其求解的困难主要在于如何处理问题的约束及时间（环境）变量。给出了一类定义在离散时间（环境）空间上的动态非线性约束优化问题的新解法,从问题的约束条件出发构造了一个新的动态熵函数,利用此函数将原优化问题转化成了两个目标的动态优化问题。进一步设计了新的杂交算子和带局部搜索的变异算子,提出了一种新的多目标优化求解进化算法。通过对两个动态非线性约束优化问题的计算仿真,表明该算法是有效的。     

A novel multi-swarm algorithm for optimization in dynamic environments based on particle swarm optimization

Optimization in dynamic environment is considered among prominent optimization problems. There are particular challenges for optimization in dynamic environments, so that the designed algorithms must conquer the challenges in order to perform an efficient optimization. In this paper, a novel optimization algorithm in dynamic environments was proposed based on particle swarm optimization approach, in which several mechanisms were employed to face the challenges in this domain. In this algorithm, an improved multi-swarm approach has been used for finding peaks in the problem space and tracking them after an environment change in an appropriate time. Moreover, a novel method based on change in velocity vector and particle positions was proposed to increase the diversity of swarms. For improving the efficiency of the algorithm, a local search based on adaptive exploiter particle around the best found position as well as a novel awakening–sleeping mechanism were utilized. The experiments were conducted on Moving Peak Benchmark which is the most well-known benchmark in this domain and results have been compared with those of the state-of-the art methods. The results show the superiority of the proposed method.     

Multiobjective optimization immune algorithm in dynamic environments and its application to greenhouse control

A novel multiobjective optimization immune algorithm in dynamic environments, as associated with Pareto optimality and immune metaphors of germinal center in the immune system, is proposed to deal with a class of dynamic multiobjective optimization problems which the dimension of the objective space may change over time. Several immune operators, depending on both somatic maturation and T-cell regulation, are designed to adapt to the changing environment so that the algorithm can achieve a reasonable tradeoff between convergence and diversity of population, among which an environmental recognition rule related to the past environmental information is established to identify an appearing environment. Preliminary experiments show that the proposed algorithm cannot only obtain great superiority over two popular algorithms, but also continually track the time-varying environment. Comparative analysis and practical application illustrate its potential.     

Self-adaptive constrained artificial bee colony for constrained numerical optimization

The artificial bee colony is a simple and effective global optimization algorithm. It has been successfully applied to solve a wide range of real-world optimization problem, and later, it was extended to constrained design problems as well. This paper describes a self-adaptive constrained artificial bee colony algorithm for constrained optimization problem based on feasible rule method and multiobjective optimization method. The employed bee colony severs as the global search engine for each population based on feasible rule. Then, the onlooker bee colony can explore the new search space based on the multiobjective optimization. In order to enhance the convergence rate of the proposed algorithm, a self-adaptive modification rate is proposed to make the algorithm can change many parameters. To verify the performance of our approach, 24 well-known constrained problems from 2006 IEEE congress on Evolution Computation (CEC2006) are employed. Experimental results indicate that the proposed algorithm performs better than, or at least comparable to, state-of-the-art approaches in terms of the quality of the resulting solutions from literature.     

动态电源管理的随机切换模型与策略优化

提出一种基于连续时间Markov决策过程的动态电源管理策略优化方法.通过建立动态电源管理系统的随机切换模型,将动态电源管理问题转化为带约束的策略优化问题,并给出一种基于矢量合成的策略梯度优化算法.随机切换模型对动态电源管理系统的描述精确,策略优化算法简便有效,既能离线计算,也适用于在线优化.仿真实验验证了该方法的有效性.     

动态分级的并行约束优化进化算法

提出一种动态分级的并行进化算法用于求解约束优化问题。该算法首先利用佳点集方法初始化种群。在进化过程中,将种群个体分为两个子种群,分别用于全局和局部搜索,并根据不同的搜索阶段动态调整各种级别中并行变量的数目。标准测试问题的实验结果表明了该算法的可行性和有效性。     

求解约束优化的带偏好双目标优化方法

文章提出了一种求解约束优化问题的新方法。它把约束优化问题转化为双目标优化问题,一个目标是原问题的目标,另一目标是由约束条件转化得到。转化得到的双目标优化与一般的双目标优化问题不同在于它偏好那些使约束条件满足的最优解。我们利用动态权值将这一带有偏好的双目标优化转化为无约束的单目标优化,并使其满足偏好特性。我们对四个标准测试函数进行了数据仿真实验,实验结果表明该算法是有效的。     

动态电源管理的随机切换模型与在线优化

考虑系统参数未知情况下的动态电源管理问题，提出一种基于强化学习的在线策略优化算法. 通过建立事件驱动的随机切换分析模型，将动态电源管理问题转化为带约束的Markov 决策过程的策略优化问题. 利用此模型的动态结构特性，结合在线学习估计梯度与随机逼近改进策略，提出动态电源管理策略的在线优化算法．随机切换模型对电源管理系统的动态特性描述精确，在线优化算法自适应性强，运算量小，精度高，具有较高的实际应用价值．