A novel multi-objective optimization algorithm based on Lightning Attachment Procedure Optimization algorithm

In this paper, a novel multi-objective optimization method based on a recently introduced algorithm known as Lightning Attachment Procedure Optimization (LAPO) is presented. The proposed algorithm is based on non-dominated sorting approach where the best solutions chosen from the Pareto Optimal Front (POF), based on crowding distance, are stored in a repository matrix called an Archive matrix. The procedure is performed such that the final best solutions are distributed evenly along the optimal PF. Then, the proposed algorithm is tested by some multi-objective optimization functions and some classical engineering problems also. The results are compared to those of four well-known methods and then discussed. The results are compared using 4 criteria which show how to select a POF close to the true POF, how the results are distributed, and how close the final results approximate all the possible outcomes of true POF. It is shown that the proposed method outperforms the other methods with regards to 3 criteria and yields comparable results regarding the last criteria. Superiority of the proposed method in finding the true POF while covering a wide range of possible optimal results is discussed in the results section. Therefore, it is concluded that the proposed method does an excellent job at solving a wide range of multi-objective optimization problems.     

一种改进的鲁棒多目标优化方法

针对在解决某些复杂多目标优化问题过程中,所得到的Pareto最优解易受设计参数或环境参数扰动的影响,引入了鲁棒的概念并提出一种改进的鲁棒多目标优化方法,它利用了经典的基于适应度函数期望和方差方法各自的优势,有效地将两种方法结合在一起。为了实现该方法,给出一种基于粒子群优化算法的多目标优化算法。仿真实例结果表明,所给出的方法能够得到更为鲁棒的Pareto最优解。     

Multi-objective optimal power flow using quasi-oppositional teaching learning based optimization

This paper describes teaching learning based optimization (TLBO) algorithm to solve multi-objective optimal power flow (MOOPF) problems while satisfying various operational constraints. To improve the convergence speed and quality of solution, quasi-oppositional based learning (QOBL) is incorporated in original TLBO algorithm. The proposed quasi-oppositional teaching learning based optimization (QOTLBO) approach is implemented on IEEE 30-bus system, Indian utility 62-bus system and IEEE 118-bus system to solve four different single objectives, namely fuel cost minimization, system power loss minimization and voltage stability index minimization and emission minimization; three bi-objectives optimization namely minimization of fuel cost and transmission loss; minimization of fuel cost and L-index and minimization of fuel cost and emission and one tri-objective optimization namely fuel cost, minimization of transmission losses and improvement of voltage stability simultaneously. In this article, the results obtained using the QOTLBO algorithm, is comparable with those of TLBO and other algorithms reported in the literature. The numerical results demonstrate the capabilities of the proposed approach to generate true and well-distributed Pareto optimal non-dominated solutions of the multi-objective OPF problem. The simulation results also show that the proposed approach produces better quality of the individual as well as compromising solutions than other algorithms.     

数据驱动选择策略的多目标差分进化算法

针对多目标差分进化算法求解复杂多目标优化问题时,最优解选择策略中非支配排序计算复杂度高的问题,提出一种数据驱动选择策略的多目标差分进化(MODE-DDSS)算法.首先,设计多目标差分进化算法的优化解排序等级评估准则,建立基于评估准则的优化解排序等级评估库;其次,设计基于优化解双向搜索机制和无重复比较机制的数据驱动选择策略,实现优化解的高效搜索和快速排序;最后,构建数据驱动选择策略的多目标差分进化算法,降低算法在最优解选择操作中的时间复杂度,提高算法的寻优效率.实验结果表明,所提出的MODE-DDSS算法能够有效减少最优解在选择过程中的比较次数,提升多目标差分进化算法解决复杂多目标优化问题的寻优效率.     

解多目标优化问题的新粒子群优化算法

通过定义的粒子序值方差和U-度量方差,把对任意多个目标函数的优化问题转化成为两个目标函数的优化问题。继而把Pareto最优与粒子群优化(PSO)算法相结合,对转化后的优化问题提出了一种新的多目标粒子群优化算法,并证明了其收敛性。新方法用较少计算量便可以求出一组在最优解集合中分布均匀且数量充足的最优解。计算机仿真表明该算法对不同的试验函数均可用较少计算量求出在最优解集合中分布均匀且数量充足的最优解。     

A self-adaptive multi-objective harmony search algorithm based on harmony memory variance

Although harmony search (HS) algorithm has shown many advantages in solving global optimization problems, its parameters need to be set by users according to experience and problem characteristics. This causes great difficulties for novice users. In order to overcome this difficulty, a self-adaptive multi-objective harmony search (SAMOHS) algorithm based on harmony memory variance is proposed in this paper. In the SAMOHS algorithm, a modified self-adaptive bandwidth is employed, moreover, the self-adaptive parameter setting based on variation of harmony memory variance is proposed for harmony memory considering rate (HMCR) and pitch adjusting rate (PAR). To solve multi-objective optimization problems (MOPs), the proposed SAMOHS uses non-dominated sorting and truncating procedure to update harmony memory (HM). To demonstrate the effectiveness of the SAMOHS, it is tested with many benchmark problems and applied to solve a practical engineering optimization problem. The experimental results show that the SAMOHS is competitive in convergence performance and diversity performance, compared with other multi-objective evolutionary algorithms (MOEAs). In the experiment, the impact of harmony memory size (HMS) on the performance of SAMOHS is also analyzed.     

多种人工智能算法的数据库技术课程自动组卷比较

在线考试被广泛应用在远程教育上,自动化组卷是在线考试的关键技术,组卷问题即是多目标期望值的求解问题,其往往存在多个解,人工智能算法对于求解多目标函数有明显优势.采用遗传算法及蚁群算法的多目标优化求解更加高效,能更好胜任于本文数据库技术课程的自动化组卷.在讨论人工智能算法在组卷应用基础上,构建了组卷指标体系,建立多目标约束数学模型,并对多目标期望值进行优化求解.多次实验结果论证表明,人工智能算法的成功率最高,平均达到98%以上（含蚁群算法100%,遗传算法96%）,而非人工智能的算法成功率较低,随机变量法62%,回溯试探法84%.应用人工智能方法特别是遗传算法和蚁群算法,提升了自动化组卷效率,满足了实际各种组卷的需要,使其在远程教育和在线考试中有很好的应用前景.     

最大化个人偏好的多目标优化进化算法

针对多目标优化过程中如何将个人偏好信息融入寻优搜索过程的问题,本文提出一种最大化个人偏好 以确定搜索方向的多目标优化进化算法．该算法首先采用权重和法将多目标问题转换为单目标问题,再利用遗传算 法进行全局搜索,在满足个人偏好约束条件下,每一代进化结束后通过解约束优化问题获得能够使种群综合适应度 具有最大方差的权重组合,从而最大化个人偏好以选择综合最优的个体进行遗传操作．按照不同个人偏好应用于传 动系统进行控制器设计,仿真结果表明该算法能够获得满足个人偏好约束条件下的全局最优解．     

基于价值迭代算法的最优渗透路径发现

渗透测试的核心是发现渗透路径, 但并不是所有的渗透路径都能够成功, 所以需要基于当前系统环境选择最优渗透路径. 在此背景下, 首先, 本文基于攻击图将环境建模为马尔可夫决策过程(Markov decision process, MDP)图, 使用价值迭代算法寻找最优渗透路径. 其次, 对于渗透测试过程中存在的渗透动作失效问题, 提出了一种新的重规划算法, 可以在MDP图中有效处理失效渗透动作, 重新寻找最优渗透路径. 最后, 基于渗透测试过程中存在多个攻击目标的情况, 本文提出了面向MDP图的多目标全局最优渗透路径算法. 实验证明, 本文提出的算法在重规划任务方面, 表现出了更高的效率和稳定性, 在多目标任务方面, 体现出了算法的有效性, 可以避免不必要的渗透动作被执行.     

QPSO算法求解无约束多目标优化问题

在分析了用基于目标加权的PSO算法(WAPSO)的基础上,研究了利用基于量子行为的微粒群优化算法(QPSO)来解决多目标优化问题.提出了基于目标加权的QPSO算法(WAQPSO),利用WAQPSO算法解决无约束的多目标优化问题,通过典型的多目标测试函数实验,验证了该算法解决无约束多目标问题的有效性.     

一种基于新的模型的多目标存档遗传算法

在多目标优化中,如何在最优解集中获得一组分布均匀且质量较好的代表解是十分重要的。文中给出了种群个体的序和解的均匀性分布定义,在此基础上又给出了解的序值方差和U-度量方差,然后把对任意多个目标函数的优化问题转化成对两个目标函数的优化问题,并对转化后的优化问题提出了一种新的多目标存档遗传算法,并证明了其全局收敛性。数据实验比较表明该算法能找到问题的数量更多、分布更广、更均匀的Pareto最优解。     

基于多优化目标的软件测试用例约简方法研究

软件测试是软件工程的一个重要组成部分,其目标是能够及时发现软件中的错误,确保软件高质量。测试用例是软件测试的基础,覆盖度较高且精简的测试用例集可以提高测试效率和降低成本。软件测试覆盖标准较多,一个好的测试用例评价指标也存在多种,为了能够在约简测试用例集规模的同时获取较高的测试能力,本文提出了一种基于多优化目标的测试用例集约简算法,该算法旨在根据测试用例需求,构建多优化目标的测试用例模型,使用该模型获取一个最优解的测试用例子集,使用最小化用例集方法最小化测试用例,迭代执行直到测试用例集覆盖所有的测试需求,实验结果表明该算法可以约简测试用例集,获取较高的综合测试效果。     

结合批量问题的多目标矩形件优化排样

设计多目标启发式进化算法,研究了一种考虑批量问题的二维矩形件排样问题,建立了含有原材料成本最小化和零件库存成本最小化的多目标优化模型。先用启发式算法初始化下料方式,再用改进的快速非支配排序算法进行优化求解,确定下料方案。通过实验结果以及与其他算法的对比表明,在中等规模的矩形件排样问题中,该算法能够在较快的时间内既保证较高的原料利用率,又能降低该问题的总成本,证明了该算法的有效性。     

A hybrid multi-objective shuffled frog-leaping algorithm for a mixed-model assembly line sequencing problem

In this paper, a mixed-model assembly line (MMAL) sequencing problem is studied. This type of production system is used to manufacture multiple products along a single assembly line while maintaining the least possible inventories. With the growth in customers’ demand diversification, mixed-model assembly lines have gained increasing importance in the field of management. Among the available criteria used to judge a sequence in MMAL, the following three are taken into account: the minimization of total utility work, total production rate variation, and total setup cost. Due to the complexity of the problem, it is very difficult to obtain optimum solution for this kind of problems by means of traditional approaches. Therefore, a hybrid multi-objective algorithm based on shuffled frog-leaping algorithm (SFLA) and bacteria optimization (BO) are deployed. The performance of the proposed hybrid algorithm is then compared with three well-known genetic algorithms, i.e. PS-NC GA, NSGA-II, and SPEA-II. The computational results show that the proposed hybrid algorithm outperforms the existing genetic algorithms, significantly in large-sized problems.     

A multi-objective TLBO algorithm for balancing two-sided assembly line with multiple constraints

Two-sided assembly line is often designed to produce large-sized high-volume products such as cars, trucks and engineering machinery. However, in real-life production process, besides the elementary constraints in the one-sided assembly line, additional constraints, such as zoning constraints, positional constraints and synchronous constraints, may occur in the two-sided assembly line. In this paper, mathematical formulation of balancing multi-objective two-sided assembly line with multiple constraints is established, and some practical objectives, including maximization of the line efficiency, minimization of the smoothness index and minimization of the total relevant costs per product unit (Tcost), have been considered. A novel multi-objective optimization algorithm based on improved teaching–learning-based optimization (ITLBO) algorithm is proposed to obtain the Pareto-optimal set. In the ITLBO algorithm, teacher and learner phases are modified for the discrete problem, and late acceptance hill-climbing is integrated into a novel self-learning phase. A novel merging method is proposed to construct a new population according to the ordering relation between the original and evolutionary population. The proposed algorithm is tested on the benchmark instances and a practical case. Experimental results, compared with the ones computed by other algorithm and in current literature, validate the effectiveness of the proposed algorithm.     

A hybrid multi-objective shuffled frog-leaping algorithm for a mixed-model assembly line sequencing problem

In this paper, a mixed-model assembly line (MMAL) sequencing problem is studied. This type of production system is used to manufacture multiple products along a single assembly line while maintaining the least possible inventories. With the growth in customers’ demand diversification, mixed-model assembly lines have gained increasing importance in the field of management. Among the available criteria used to judge a sequence in MMAL, the following three are taken into account: the minimization of total utility work, total production rate variation, and total setup cost. Due to the complexity of the problem, it is very difficult to obtain optimum solution for this kind of problems by means of traditional approaches. Therefore, a hybrid multi-objective algorithm based on shuffled frog-leaping algorithm (SFLA) and bacteria optimization (BO) are deployed. The performance of the proposed hybrid algorithm is then compared with three well-known genetic algorithms, i.e. PS-NC GA, NSGA-II, and SPEA-II. The computational results show that the proposed hybrid algorithm outperforms the existing genetic algorithms, significantly in large-sized problems.     

基于联盟构造博弈的认知无线电网络分布式多目标协作感知算法

协作感知技术可提高认知无线电网络中的频谱资源利用率,但网络节点在形成协作感知联盟的同时也不可避免地引入了额外开销,联盟内节点总希望用较少的额外能量开销达到较大的吞吐量期望.为此,文中提出了协作感知系统的多目标非线性优化问题,然后基于联盟博弈理论为该问题构建了一个不可转移支付的联盟构造博弈模型,在其核心的支付函数的设计中,采用线性加权和的方法同时考虑了节点吞吐最期望和能量消耗两个优化目标.基于该函数,提出了一种分布式多目标联盟构造算法DMCF,其核心是根据优超算子所定义的联盟的帕累托顺序,循环地对联盟进行合并和分裂操作.此外,还证明了DMCF的收敛性和最终联盟划分的稳定性.仿真实验的结果表明,DMCF可有效解决提出的多目标优化问题,与一种分布式随机联盟构造算法DRCF相比,DMCF总能使节点消耗较少能量却达到相对较大的吞吐量期望.在不同网络规模下,DMCF可获得的节点平均吞吐量期望可提升约7.5％,而节点平均能量消耗却可降低约70％.     

无参分组大规模变量的多目标算法研究

目前大多数多目标优化算法没有考虑到决策变量之间的交互性,只是将所有变量当作一个整体进行优化。随着决策变量的增加,多目标优化算法的性能会急剧下降。针对上述问题,提出一种无参变量分组的大规模变量的多目标优化算法(MOEA/DWPG)。该算法将协同优化与基于分解的多目标优化算法(MOEA/D)相结合,设计了一种不含参数的分组方式来提高交互变量分组的精确性,提高了算法处理含有大规模变量的多目标优化算法的性能。实验结果表明,该算法在大规模变量多目标问题上明显优于MOEA/D及其它先进算法。     

基于双重权约束期望改进策略的多目标并行代理优化方法

针对多目标仿真优化的高昂成本及黑箱函数难以获取问题,提出基于双重权约束期望改进策略的多目标并行代理优化方法.首先,建立Kriging模型获取未试验点的预测不确定性;其次,构建双重权约束期望改进策略,并利用填充策略矩阵及距离聚合方法实现新改进策略的聚合;然后,最大化聚合双重权约束期望改进策略实现多目标并行优化;最后,达到终止条件,获得Pareto最优解集.选取测试函数及铰接夹芯梁设计案例进行优化验证.验证对比结果表明:所提方法可有效提升多目标问题优化效率,减少昂贵仿真成本;与同类方法相比,低维问题中获取Pareto最优解集的收敛性、多样性及分布性更优.     

趋磁性细菌多目标优化算法

提出趋磁性细菌多目标优化算法(MTBMO).该算法以趋磁性细菌优化算法(MBOA)中磁小体(MTSs)的生成机制为基础,设计适用于多目标优化的新型MTSs磁矩调节机制,确保群体的收敛性;同时采用基于混沌变异的替换方法取代MBOA中的磁小体替换机制来增强群体的多样性.通过标准函数测试和与现有多目标优化算法的比较表明,MTBMO对于求解多目标优化问题(MOPs)是可行且有效的.