基于Pareto的多目标优化免疫算法

免疫算法具有搜索效率高、避免过早收敛、群体优化、保持个体多样性等优点。将其应用于多目标优化问题,建立了一种新型的基于Pareto的多目标优化免疫算法(MOIA)。算法中,将优化问题的可行解对应抗体,优化问题的目标函数对应抗原,Pareto最优解被保存在记忆细胞集中,并利用有别于聚类的邻近排挤算法对其进行不断更新,进而获得分布均匀的Pareto最优解。文章最后,对MOIA算法与文献[3]中SPEA算法进行仿真,通过比较两者的收敛性和分布性,得到了MOIA优于SPEA的结论。     

基于IFI与FUA的Pareto遗传算法

在适应值快速辨识算法和基于聚类排挤的外部种群快速替换算法的基础上，提出了搜索Pareto最优解集的快速遗传算法。在该算法中，IFI算法实现个体适应值的快速辨识，FUA维持种群多样度和Pareto最优解集的均匀分布性。采用FPGA算法对多种多目标0/1背包问题进行仿真优化，FPGA算法能够以较少的计算成本搜索到高精度、分布均匀、高质量的Pareto非劣解集，收敛速度和收敛准确性均优于强度Pareto进化算法(SPEA)。     

嵌入用户偏爱区域的多目标优化算法

针对已有的多目标优化方法在实际应用中存在的问题,给出了基于用户偏爱区域的多目标优化算法.它只求出与用户偏爱区域相关的部分Pareto最优集,从而减少了解的数量,加快了收敛速度.算法运用了精英非受控排序策略,并以个体与用户偏爱区域的距离作为影响适应值的一个因素,运用排挤策略实现解在Pareto边界分布的均匀性.仿真结果表明算法有效.     

一种新的多目标改进和声搜索优化算法

针对标准和声搜索算法存在收敛不稳定及不能用于多目标优化问题的缺陷,通过引入交叉算子、自适应记忆内搜索概率和调节概率,改进了传统的和声搜索算法;根据Pareto支配关系,结合算法和声记忆库内信息完全共享的特性,提出了基于动态Pareto最优前沿的能够求解多目标优化问题的多目标改进和声搜索算法。通过几个典型函数的仿真测试表明,提出的算法能够高效稳定地收敛于Pareto最优前沿,获得分布均匀的Pareto解集。     

基于精英选择和个体迁移的多目标遗传算法

提出基于遗传算法求解多目标优化问题的方法,将多目标问题分解成多个单目标优化问题,用遗传算法分别在每个单目标种群中并行搜索.在进化过程中的每一代,采用精英选择和个体迁移策略加快多个目标的并行搜索,提出了控制Pareto最优解数量并保持个体多样性的有限精度法,同时还提出了多目标遗传算法的终止条件.数值实验说明所提出的算法能较快地找到一组分布广泛且均匀的Pareto最优解.     

基于Pareto的快速多目标克隆选择算法*

基于免疫系统中克隆选择原理,提出了一种多目标克隆选择算法MCSA。该方法只对部分当前所得到的Pareto最优解进行进化操作,所求得的Pareto最优解保留在一个不断更新的外部记忆库中,并选用一种简单的多样性保存机制来保证其具有良好的分布特征。实验结果表明,该方法能够很快地收敛到Pareto最优前沿面,同时较好地保持解的多样性和分布的均匀性。对于公认的多目标benchmark问题,MCSA在解集分布的均匀性、多样性与解的精确性及算法收敛速度等方面均优于SPEA、NSGA-II等算法。     

蚁群遗传算法的多目标优化

为了求解带有约束条件的多目标函数优化问题,提出基于连续空间优化的多目标蚁群遗传算法。针对多目标优化问题的特点,定义连续空间中利用信息量指导遗传搜索策略和信息更新方法,将信息量指导遗传搜索、优秀决策引入、决策集更新、改变算法终止条件等方式相结合,有效地加速了搜索的收敛速度,控制了Pareto最优决策集的数量,扩大了决策的分布范围,维持了决策的多样性。数值实验说明该算法能够快速找到一组分布广泛的Pareto最优决策。     

基于量子行为特性粒子群和自适应网格的多目标优化算法

为了能够找到更多真实的Pareto最优解和提高所求最优解的分布均匀性,提出了一种新型的基于量子行为特性粒子群优化和自适应网格的多目标量子粒子群优化算法.利用量子行为特性粒子群优化算法的寻优优势快速地接近真实的Pareto最优解,引入高斯变异算子增强搜索解的多样性.通过设置一个外部存储器保留搜索过程中找到的Pareto最优解,采用自适应网格法对外部存储器中最优解进行更新和维护操作,使得从中选择的领导粒子能够引导粒子群最终找到真实的Pareto最优解.仿真结果表明所提算法具有更好的收敛性能和更均匀的分布性能.     

分散搜索算法求解多目标优化问题

最近涌现了各种进化方法来解决多目标优化问题,分散搜索也是一种可以解决多目标问题的算法。该算法的结构引用进化算法的杂交和变异算子来增强它的性能,但该算法与其他进化算法的不同在于一系列操作策略不再基于随机性原理,而是运用"分散-收敛集聚"的迭代机制。论文在多目标优化问题区域讨论分散搜索算法,寻找多目标的非支配集或Pareto最优解。实验表明,分散搜索算法具有很好的收敛性和分布性。     

基于正交设计的动态多目标优化算法

提出了一种基于正交设计的动态多目标优化算法(ODMOA),当环境变化时通过分析动态多目标优化问题的特点,利用历史信息对新环境下的Pareto最优解集进行预测,得到一个新的预测种群;否则在静态环境下使用正交试验法在解空间内进行系统且高效的搜索,使算法能够在当前环境下快速收敛到最优解。进行了多组对比试验,验证了该算法的有效性。     

An orthogonal multi-objective evolutionary algorithm for multi-objective optimization problems with constraints

In this paper, an orthogonal multi-objective evolutionary algorithm (OMOEA) is proposed for multi-objective optimization problems (MOPs) with constraints. Firstly, these constraints are taken into account when determining Pareto dominance. As a result, a strict partial-ordered relation is obtained, and feasibility is not considered later in the selection process. Then, the orthogonal design and the statistical optimal method are generalized to MOPs, and a new type of multi-objective evolutionary algorithm (MOEA) is constructed. In this framework, an original niche evolves first, and splits into a group of sub-niches. Then every sub-niche repeats the above process. Due to the uniformity of the search, the optimality of the statistics, and the exponential increase of the splitting frequency of the niches, OMOEA uses a deterministic search without blindness or stochasticity. It can soon yield a large set of solutions which converges to the Pareto-optimal set with high precision and uniform distribution. We take six test problems designed by Deb, Zitzler et al., and an engineering problem (W) with constraints provided by Ray et al. to test the new technique. The numerical experiments show that our algorithm is superior to other MOGAS and MOEAs, such as FFGA, NSGAII, SPEA2, and so on, in terms of the precision, quantity and distribution of solutions. Notably, for the engineering problem W, it finds the Pareto-optimal set, which was previously unknown.     

基于Pareto最优的PID多目标优化设计

现有的PID优化方法往往难以同时兼顾系统对时域和频域性能的要求,针对这一缺陷,提出了一种PID多目标优化方法：将动态性能指标作为优化目标,频域性能指标作为约束条件,采用基于Pareto最优的多目标优化算法对其求解。该算法采用新的拥挤距离计算方法,引入双重精英机制,进化效率高,得到的Pareto最优解集多样性好,决策者可根据当前工作需求从中选择最终的满意解。仿真结果证明了本文方法的有效性。     

一种维持种群多样性的多目标差分演化算法

差分演化算法是一种简单而有效的全局优化算法。本文将差分演化算法用于求解多目标优化问题,给出了一种维持种群多样性的多目标差分演化算法。该算法采用正交设计法初始化种群,改进差分演化算子,从而有利于维持种群多样性,提高演化算法的搜索性能。初步实验表明,新算法能有效地求解多目标优化问题。     

基于ε占优的正交多目标差分演化算法研究

演化多目标优化是目前演化计算中热门研究方向之一.但是,要设计一种高效、鲁棒的演化多目标优化算法,使其找到接近最优和完整的非劣解集是一项很困难的任务.为了能有效求解多目标优化问题,提出了一种新的多目标差分演化算法.新算法具有如下特征:1)利用正交实验设计和连续空间量化的方法产生初始群体,使得初始群体中的个体可以均匀分布于搜索空间,并且可以使好的个体在演化过程中得到利用;2)采用Archive群体保存非劣解,并利用ε占优方法更新Archive群体,从而可以使算法较快获得分布很好的Pareto解集;3)为了加快算法收敛,提出一种基于随机选择和精英选择的混合选择机制.通过8个标准测试函数对新算法进行测试,并与其他一些多目标演化算法进行比较,其结果表明新算法可以有效逼近真实Pareto前沿且分布均匀,并且在收敛性和多样性的求解精度和稳     

一种基于云模型的多目标进化算法

在多目标进化算法的基础上,提出了一种基于云模型的多目标进化算法(CMOEA).算法设计了一种新的变异算子来自适应地调整变异概率,使得算法具有良好的局部搜索能力.算法采用小生境技术,其半径按X条件云发生器非线性动态地调整以便于保持解的多样性,同时动态计算个体的拥挤距离并采用云模型参数来估计个体的拥挤度,逐个删除种群中超出的非劣解以保持解的分布性.将该算法用于多目标0/1背包问题来测试CMOEA的性能,并与目前最流行且有效的多目标进化算法NSGA-II及SPEA2进行了比较.结果表明,CMOEA具有良好的搜索性能,并能很好地维持种群的多样性,快速收敛到Pareto前沿,所获得的Pareto最优解集具有更好的收敛性与分布性.     

Handling multiple objectives with biogeography-based optimization

Biogeography-based optimization (BBO) is a new evolutionary optimization method inspired by biogeography. In this paper, BBO is extended to a multi-objective optimization, and a biogeography-based multi-objective optimization (BBMO) is introduced, which uses the cluster attribute of islands to naturally decompose the problem. The proposed algorithm makes use of nondominated sorting approach to improve the convergence ability effciently. It also combines the crowding distance to guarantee the diversity of Pareto optimal solutions. We compare the BBMO with two representative state-of-the-art evolutionary multi-objective optimization methods, non-dominated sorting genetic algorithm-II (NSGA-II) and archive-based micro genetic algorithm (AMGA) in terms of three metrics. Simulation results indicate that in most cases, the proposed BBMO is able to find much better spread of solutions and converge faster to true Pareto optimal fronts than NSGA-II and AMGA do.     

Solution of multiobjective optimization problems: coevolutionary algorithm based on evolutionary game theory

When attempting to solve multiobjective optimization problems (MOPs) using evolutionary algorithms, the Pareto genetic algorithm (GA) has now become a standard of sorts. After its introduction, this approach was further developed and led to many applications. All of these approaches are based on Pareto ranking and use the fitness sharing function to keep diversity. On the other hand, the scheme for solving MOPs presented by Nash introduced the notion of Nash equilibrium and aimed at solving MOPs that originated from evolutionary game theory and economics. Since the concept of Nash Equilibrium was introduced, game theorists have attempted to formalize aspects of the evolutionary equilibrium. Nash genetic algorithm (Nash GA) is the idea to bring together genetic algorithms and Nash strategy. The aim of this algorithm is to find the Nash equilibrium through the genetic process. Another central achievement of evolutionary game theory is the introduction of a method by which agents can play optimal strategies in the absence of rationality. Through the process of Darwinian selection, a population of agents can evolve to an evolutionary stable strategy (ESS). In this article, we find the ESS as a solution of MOPs using a coevolutionary algorithm based on evolutionary game theory. By applying newly designed coevolutionary algorithms to several MOPs, we can confirm that evolutionary game theory can be embodied by the coevolutionary algorithm and this coevolutionary algorithm can find optimal equilibrium points as solutions for an MOP. We also show the optimization performance of the co-evolutionary algorithm based on evolutionary game theory by applying this model to several MOPs and comparing the solutions with those of previous evolutionary optimization models. This work was presented, in part, at the 8th International Symposium on Artificial Life and Robotics, Oita, Japan, January 24#x2013;26, 2003.     

Multi-objective modified differential evolution algorithm with archive-base mutation for solving multi-objective $$$$-xylene oxidation rocess

Maximizing the diversity of the obtained objective vectors and increasing the convergence speed to the true Pareto front are two important issues in the design of multi-objective evolutionary algorithms (MOEAs). To solve complex multi-objective optimization problems (MOPs), a multi-objective modified differential evolution algorithm with archive-base mutation (MOMDE-AM) is proposed. In MOMDE-AM, with the purpose of reducing the loss of population evolution information, a modified mutation strategy with archive is introduced, which could utilize several useful inferior solutions and provide promising direction information toward the true Pareto front. The performance of MOMDE-AM is compared with five other MOEAs on five bi-objective and five tri-objective optimization problems. The simulation and statistical analysis results indicate that the overall performance of MOMDE-AM is better than those of the compared algorithms on these test functions. Finally, MOMDE-AM is used to optimize ten operation conditions of the \(p\)-xylene oxidation reaction process; the results show that MOMDE-AM is an effective and efficient optimization tool for solving actual MOPs.     

基于权重学习的高维多目标进化算法

在多目标进化算法解决多目标优化问题的过程中,随着目标个数的增加,种群个体进化方向的盲目性逐渐显露出来,同时还存在着收敛性和多样性难以平衡的问题。针对以上两个问题,以基于参考点策略的快速非支配排序遗传算法NSGA-Ⅲ为框架,分别从产生候选解和选择候选解两个角度进行算法改进,从而得到一个新的进化算法WL-NSGAⅢ。在新算法的匹配选择阶段,设计了一种基于权重的个体学习策略,即利用种群信息构建代内关系为种群个体提供进化方向并增加候选解集的收敛性。同时,在新算法的环境选择阶段,利用权重信息对小生境选择策略进行改进。为了验证新算法的有效性,通过模拟实验将新算法与现有算法在DTLZ问题测试集中进行比较。仿真结果表明,新算法在大多数基准问题上具有良好的效果。