包装废弃物回收车辆路径问题的改进遗传算法

目的采用优化传统遗传算法(GA)研究包装废弃物回收车辆路径问题(VRP)的性能。方法提出改进遗传算法(IGA)。首先,设计基于贪婪算法的初始种群生成算子,提高初始种群质量;其次,设计根据适应度值大小、进化代数等自适应调整的交叉和变异概率;然后,设计最大保留交叉算子,保证种群的多样性;最后,对企业实例和标准算例进行仿真测试。结果采用IGA算法、蚁群算法(ACO)能求得算例最优解,且IGA算法运行速度快于ACO算法,分支界定算法(BBM)、传统GA算法无法求得算例最优解。结论与BBM算法、传统GA算法和ACO算法相比,IGA算法求解包装废弃物回收VRP问题的整体性能更优。     

学术前沿

正包装废弃物回收车辆路径问题的改进遗传算法作者:张异来源:包装工程,2018 (9)目的 -采用优化传统遗传算法(GA)研究包装废弃物回收车辆路径问题(VRP)的性能。方法 -提出改进遗传算法(IGA)。首先,设计基于贪婪算法的初始种群生成算子,提高初始种群质量;其次,设计根据适应度值大小、进化代数等自适应调整的交叉和变异概率;然后,设计最大保留交叉算子,保证种群的多样性;最后,     

基于包装配送问题的混沌蛙跳布谷鸟算法研究

目的设计一种求解包装配送问题的混沌蛙跳布谷鸟算法(ChaoticFrogLeapingCuckooSearch Algorithm,CFLCSA)。方法对鸟巢个体进行实数编码,引入混沌机制和随机蛙跳算法,增强算法种群多样性和局部搜索能力,并利用E-n33-k4和E-n76-k8算例来验证算法的求解性能。结果 CFLCSA算法能够求得E-n33-k4已知最优解,求得E-n76-k8的最短配送距离与已知最优解的误差仅为5.03%,且算法求解结果及平均运行时间均优于混沌蚁群算法(Chaotic Ant Colony Algorithm, CACA)、改进遗传算法(Improved Genetic Algorithm, IGA)和禁忌搜索算法(Tabu Search, TS)。结论 CFLCSA算法求解性能优于CACA算法、IGA算法和TS算法,是一种较好的包装配送问题求解方法。     

关于遗传算法公理化模型的进一步结果

本文考虑由公理化所描述的抽象遗传算法,证明了算法种群列以概率1完全收敛到最优种群集,所获结果应用到具体的遗传算法策略时,能明确提出各有关参数的设置策略,使之具有所述收敛性,当变异概率趋于零时,证明了种群列依概率收敛到一致最优种群集,对父代种群参于竞争和杰出者选择遗传算法,证明了这上敛结果不依整于种群规模的杂交算子。     

基于粒子群遗传算法的泊车系统路径规划研究

针对智能停车库自动导引运输车(automated guided vehicle,AGV)存取车路径规划问题,提出了一种基于粒子群和遗传算法的动态自适应混合算法.在标准粒子群算法和遗传算法的基础上,通过引入动态自适应调整策略分别对惯性权重系数、学习因子以及交叉变异概率公式进行了优化.在进化初期,通过在惯性权重系数和学习因子之间建立动态联动关系来实现对粒子速度和位置的实时有效更新;在进化后期,通过引入自适应遗传算法的交叉、变异操作来增强混合算法的全局搜索能力,提高算法的进化速度和收敛精度.为验证混合算法的可行性和有效性,选用MATLAB软件对其进行仿真测试.仿真测试结果显示,与禁忌搜索算法、蚁群算法以及遗传算法相比,混合算法表现出较强的全局搜索能力和较好的收敛性能,表明混合算法可行和有效.     

一种新的混合遗传算法及其性能分析

为了提高遗传算法的局部搜索能力并改善其收敛性能，根据遗传算法和单纯形算法的特点，提出了一种新的混合遗传算法。数值实验表明：该算法的收敛性能、在线性能和离线性能均优于原遗传算法。     

一种改进的广义遗传算法及其在结构动力优化问题中的应用

该文提出了一种改进的广义遗传算法。算法中引入了异种机制以提高种群的多样性,在保证收敛速度的同时防止早熟收敛。该方法应用于随机风载荷作用下有应力约束的多参数结构动力响应优化问题,数值算例表明:异种机制能够有效地提高广义遗传算法收敛于全局最优解的概率并加快收敛速度;带有异种机制的广义遗传算法能够有效地求解复杂的结构动力优化问题。     

基于IAGA-BP神经网络的电地热室内温度预测

利用电地热对居民区进行供暖时,为实现对用户室内下一时刻温度的精确预测,该文提出一种改进的自适应遗传算法(IAGA)。该算法对自适应遗传算法的交叉概率和变异概率进行改进,通过函数测试证明所提算法比传统的遗传算法稳定性好、收敛速度快,并将改进后的算法对BP网络进行优化,从而克服BP网络算法易陷入局部极值、学习效率低和收敛速度慢的缺点,最终建立基于IAGA-BP网络的电地热室内温度预测模型。将其与粒子群算法(PSO)优化的BP神经网络模型进行仿真对比,实验表明:IAGA-BP网络相对于PSO-BP网络具有更好的预测准确度,其平均绝对误差、均方差分别为0.132 8℃、0.079 2,均优于PSO-BP网络预测,该模型建立可为后期的电地热温度控制提供依据。     

(μ,λ)演化策略的收敛定理

给出（μ，λ）型深化策略的一个一般的收敛定理并给出其在实际算法中的两个应用，对连续目标函数，通过研究算法种群达到目标函数全局极大解集邻域的概率，得到此概率的一个递推估计式。利用此估计式给出算法种群依概率收敛于目标函数全局最优解集的一个有价值的充分条件。     

基于蛙跳思想的量子编码遗传算法

量子门旋转相位、变异概率大小的确定,是目前制约量子遗传算法效率的两个主要问题。本文提出一种基于蛙跳思想的量子编码遗传算法(QRGA),该算法采用自适应的方式对量子旋转门旋转角进行调整,并基于模糊逻辑将蛙跳的步长进行量化以指导变异概率调整,保证进化的方向性和提高算法效率,对比实验结果表明算法可以避免陷入局部最优解,并能快速收敛到全局最优解,在运行时间和解的性能上都取得了较好的效果。     

Machining fixture layout optimisation under dynamic conditions based on evolutionary techniques

Optimisation of fixture layout is critical to reduce geometric and form error of the workpiece during the machining process. In this paper the optimal placement of fixture elements (locator and clamp locations) under dynamic conditions is investigated using evolutionary techniques. The application of the newly developed particle swarm optimisation (PSO) algorithm and widely used genetic algorithm (GA) is presented to minimise elastic deformation of the workpiece considering its dynamic response. To improve the performances of GA and PSO, an improved GA (IGA) obtained by basic GA (GA) with sharing and adaptive mutation and an improved PSO (IPSO) obtained by basic PSO (PSO) incorporated into adaptive mutation are developed. ANSYS parametric design language (APDL) of finite element analysis is employed to compute the objective function for a given fixture layout. Three layout optimisation cases derived from the high speed slot milling case are used to test the effectiveness of the GA, IGA, PSO and IPSO based approaches. The comparisons of computational results show that IPSO seems superior to GA, IGA and PSO approaches with respect to the trade-off between global optimisation capability and convergence speed for the presented type problems.     

一种改进的广义遗传算法及其在鲁棒优化问题中的应用

提出一种改进的广义遗传算法,算法中引入了异种机制以提高种群的多样性,在保证收敛速度的同时防止了早熟收敛。将该方法应用于复杂载荷作用下结构的鲁棒优化问题,并采用Taguchi望目特性的SN比构造了遗传算法的目标函数。数值算例表明,异种机制能够有效地提高广义遗传算法收敛于全局最优解的概率,加快收敛速度;结合了Taguchi鲁棒设计方法的广义遗传算法能够有效地求解复杂载荷作用下带有不确定参数的结构鲁棒优化问题。     

Improved genetic algorithm for mixed-discrete-continuous design optimization problems

An improved genetic algorithm (IGA) is presented to solve the mixed-discrete-continuous design optimization problems. The IGA approach combines the traditional genetic algorithm with the experimental design method. The experimental design method is incorporated in the crossover operations to systematically select better genes to tailor the crossover operations in order to find the representative chromosomes to be the new potential offspring, so that the IGA approach possesses the merit of global exploration and obtains better solutions. The presented IGA approach is effectively applied to solve one structural and five mechanical engineering problems. The computational results show that the presented IGA approach can obtain better solutions than both the GA-based and the particle-swarm-optimizer-based methods reported recently.     

基于免疫遗传算法优化的模糊神经元网络控制器在全阶精馏塔模型中的控制仿真研究

本文提出了一种免疫遗传算法优化的模糊控制器,利用免疫遗传算法的全局搜索功能和神经元的自学习能力,提高了模糊控制器的控制精度和抗干扰能力。将该控制器用于全阶精馏塔模型仿真,仿真结果表明该控制器可以有效地消除静态误差,并在控制过渡过程中也有很好的鲁棒性,实际应用效果也表明了该方法的优越性。     

Automated test data generation for branch testing using incremental genetic algorithm

Cost of software testing can be reduced by automated test data generation to find a minimal set of data that has maximum coverage. Search-based software testing (SBST) is one of the techniques recently used for automated testing task. SBST makes use of control flow graph (CFG) and meta-heuristic search algorithms to accomplish the process. This paper focuses on test data generation for branch coverage. A major drawback in using meta-heuristic techniques is that the CFG paths have to be traversed from the starting node to end node for each automated test data. This kind of traversal could be improved by branch ordering, together with elitism. But still the population size and the number of iterations are maintained as the same to keep all the branches alive. In this paper, we present an incremental genetic algorithm (IGA) for branch coverage testing. Initially, a classical genetic algorithm (GA) is used to construct the population with the best parents for each branch node, and the IGA is started with these parents as the initial population. Hence, it is not necessary to maintain a huge population size and large number of iterations to cover all the branches. The performance is analyzed with five benchmark programs studied from the literature. The experimental results indicate that the proposed IGA search technique outperforms the other meta-heuristic search techniques in terms of memory usage and scalability.     

基于批量划分的无等待流水车间订单接受问题研究

在无等待流水车间环境下,考虑订单分批量加工策略的订单接受问题,建立问题的数学模型。由于问题的NP难特性,提出改进的遗传算法对模型进行求解。改进的算法采用正向和反向NEH算法与随机方法产生初始种群,在算法更新过程中将禁忌搜索算法嵌入到遗传算法中来实现局部搜索,避免算法陷入局部最优。最后,算例表明批量划分策略能够有效减少订单的完成时间,实现订单总收益的最大化。通过算法对比,说明了改进遗传算法具有较好的求解效果。     

Mathematical modelling and optimisation of energy-conscious hybrid flow shop scheduling problem with unrelated parallel machines

This paper investigates an energy-conscious hybrid flow shop scheduling problem with unrelated parallel machines (HFSP-UPM) with the energy-saving strategy of turning off and on. We first analyse the energy consumption of HFSP-UPM and formulate five mixed integer linear programming (MILP) models based on two different modelling ideas namely idle time and idle energy. All the models are compared both in size and computational complexities. The results show that MILP models based on different modelling ideas vary dramatically in both size and computational complexities. HFSP-UPM is NP-Hard, thus, an improved genetic algorithm (IGA) is proposed. Specifically, a new energy-conscious decoding method is designed in IGA. To evaluate the proposed IGA, comparative experiments of different-sized instances are conducted. The results demonstrate that the IGA is more effective than the genetic algorithm (GA), simulating annealing algorithm (SA) and migrating birds optimisation algorithm (MBO). Compared with the best MILP model, the IGA can get the solution that is close to an optimal solution with the gap of no more than 2.17% for small-scale instances. For large-scale instances, the IGA can get a better solution than the best MILP model within no more than 10% of the running time of the best MILP model.     

A Grafted Genetic Algorithm for the Job-Shop Scheduling Problem

The standard genetic algorithm has limitations of a low convergence rate and premature convergence in solving the job-shop scheduling problem. To overcome these limitations, this paper presents a new improved hybrid genetic algorithm on the basis of the idea of graft in botany. Through the introduction of a grafted population and crossover probability matrix, this algorithm accelerates the convergence rate greatly and also increases the ability to fight premature convergence. Finally, the approach is tested on a set of standard instances taken from the literature and compared with other approaches. The computation results validate the effectiveness of the proposed algorithm.