基于混沌和高斯局部优化的混合差分进化算法

针对标准差分进化(DE)算法在高维复杂函数优化中易早熟收敛,进而导致搜索精度降低甚至优化失败的问题,提出一种基于混沌和高斯局部优化的混合差分进化算法(CGHDE).该算法在进化初期利用混沌的遍历性,可有效地避免算法陷入局部最优;而在进化后期,采用高斯搜索又可有效地提高收敛精度.实验表明,CGHDE算法对函数维度的敏感性大大低于标准DE算法,并且寻优能力强、稳定性好、搜索精度高,特别适合于工程中高维复杂函数的优化问题.     

一种结合自适应局部搜索的粒子群优化算法

本文提出一种结合自适应局部搜索的混合粒子群优化算法.该方法在粒子群优化算法的全局搜索过程中,使用能根据当前种群搜索状态自适应地调整局部搜索空间大小的局部搜索算法加强其局部搜索能力.采用了著名的基准函数对算法的性能进行测试,并与其他已有算法进行了比较.结果表明,这种混合粒子群优化算法能获得更高的搜索成功率和质量更好的解,特别在高维复杂函数优化上具有很强的竞争力.     

一种基于模式搜索算子的人工萤火虫优化算法

人工萤火虫算法是群智能领域近年出现的一个新的研究方向,该算法已在复杂函数优化方面取得了成功,但也存在着易陷入局部极小且进化后期收敛速度慢等问题.而模式搜索具有很强的搜索能力,但其搜索结果的好坏在很大程度上依赖于初始点的选择.结合两者的优缺点,提出一种基于搜索算子的人工萤火虫算法.该算法在人工萤火虫算法全局搜索过程中融入模式搜索法,改进人工萤火虫算法全局搜索和局部搜索能力.仿真实验结果表明,该算法收敛速度和解的精度显著地提高,是求解函数优化问题的一种可行和有效的方法.     

一种全局收敛的PSO算法及其收敛分析

在分析了速度因子对微粒群算法影响的基础上,针对以往算法的弱点,提出了一种基于Gaussian变异全局收敛的粒子群算法.该算法使用全局变异因子使粒子具有了良好的全局搜索能力,并证明了它能以概率1收敛到全局最优解.同时使用了局部变异因子,使算法在局部搜索过程中具有较高的搜索精度.典型函数优化的仿真结果表明,该算法具有寻优能力强、搜索精度高、稳定性好等优点,适合于工程应用中的函数优化问题.     

一种动态扩散粒子群算法

针对粒子群算法搜索精度不高特别是对高维函数优化性能不佳问题,提出了一种动态扩散粒子群算法（DDPSO)。该算法通过非线性函数调节惯性权重,在粒子速度更新方式上增加一个动态随机数加强粒子的搜索能力,提高算法的性能,同时在一定条件下对粒子进行重新扩散,保证种群的多样性。实验结果表明,DDPSO算法的寻优能力明显高于基本PSO及其他一些改进的PSO算法,并且该算法性能稳定,更加适合高维复杂函数优化问题。     

带双重变异算子的自适应粒子群优化算法

提出了一种双重变异自适应粒子群优化算法,该算法除了使用自适应算子来改变惯性权重外,还在搜索过程中使用非均匀变异算子对位移进行变异,扩大位移的搜索范围.当算法陷入局部收敛时,使用柯西变异算子对全局最优解进行变异,促使粒子逃离局部最优的陷阱,从而最大限度的提升算法全局搜索的性能.通过对4个标准函数的测试,新算法的全局搜索能力有了显著提高,并且能够有效避免早熟收敛的陷阱.     

基于人工蜂群算法的混沌系统参数估计

为了更准确的估计混沌系统的未知参数,提出了一种基于人工蜂群算法的混沌系统参数辨识方法,该方法将混沌系统中参数估计转化为多维变量的函数优化问题,利用搜索方程对多维空间变量进行充分搜索,通过优化人工蜂群算法计算估计值与真值之间的均方差,从而估计出混沌系统的参数. Lorenz混沌系统的参数辨识仿真实验结果表明了该方法的可行性,并且算法收敛速度快,估计精度高.     

一种全局收敛的PSO算法及其收敛分析

在分析了速度因子对微粒群算法影响的基础上,针对以往算法的弱点,提出了一种基于Gaussian变异全局收敛的粒子群算法.该算法使用全局变异因子使粒子具有了良好的全局搜索能力,并证明了它能以概率1收敛到全局最优解.同时使用了局部变异因子,使算法在局部搜索过程中具有较高的搜索精度.典型函数优化的仿真结果表明,该算法具有寻优能力强,搜索精度高,稳定性好等优点,适合于工程应用中的函数优化问题.

     

基于平滑技术和一维搜索的全局优化进化算法及其收敛性

为了解决全局优化算法中的一个难点--算法易于陷入局部极小点,设计了一个平滑函数,该函数可以消除一些局部极小点,而在包含最优点的部分,函数保持不变.这样,通过对此平滑函数的优化,局部极小点的数目就会在迭代过程中大量地减少,使算法更易找出全局极小点;根据平滑函数的性质,设计了一个新的杂交算子,此算子能自适应地产生优质的后代;利用平滑函数的性质,巧妙地将一维搜索技术用于算法的设计之中,从而使算法的速度大大提高;在此基础上,设计了一个解全局优化问题的新的高效进化算法,并且证明了其全局收敛性.最后的数值实验也表明新算法十分有效.     

求解高维函数优化的动态粒子群算法

针对基本粒子群优化算法对高维函数优化时搜索精度不高的缺陷,提出了一种动态粒子群优化算法。该算法采用了通过调节阈值对粒子运动轨迹进行动态改变的策略,使得粒子对周围环境的适应能力不受进化代数的影响,从而保证了算法在迭代后期仍具有较强的搜索能力。实验结果表明,与文献算法相比,该算法在处理高维函数优化时具有更强的寻优能力和更高的搜索精度。     

具有混合群智能行为的萤火虫群优化算法研究

萤火虫群优化算法是一种新型的群智能优化算法,基本的萤火虫群优化算法存在收敛精度低等问题。为了提高算法的性能,借鉴蜂群和鸟群的群体智能行为,改进萤火虫群优化算法的移动策略。运用均匀设计调整改进算法的参数取值。若干经典测试问题的实验仿真结果表明,引入混合智能行为大幅提升了算法的优化性能。     

基于局部搜索的反向学习竞争粒子群优化算法

为提升粒子群优化算法在复杂优化问题,特别是高维优化问题上的优化性能,提出一种基于Solis&Wets局部搜索的反向学习竞争粒子群优化算法(solis and wets-opposition based learning competitive particle swarm optimizer with local search, SW-OBLCSO). SW-OBLCSO算法采用竞争学习和反向学习两种学习机制,并设计了基于个体的局部搜索算子.利用10个常用基准测试函数和12个带有偏移旋转的复杂测试函数,在不同维度情况下将SW-OBLCSO算法与多种优化算法进行对比.实验结果表明,所提出算法在收敛速度和全局搜索能力上表现出突出的性能.对模糊认知图(fuzzy cognitive maps)学习问题的测试表明, SW-OBLCSO算法在处理实际问题时同样具有出色的性能.     

Comparative Study of Prey Predator Algorithm and Firefly Algorithm

Metaheuristic algorithms are found to be promising for difficult and high dimensional problems. Most of these algorithms are inspired by different natural phenomena. Currently, there are hundreds of these metaheuristic algorithms introduced and used. The introduction of new algorithm has been one of the issues researchers focused in the past fifteen years. However, there is a critic that some of the new algorithms are not in fact new in terms of their search behavior. Hence, a comparative study in between existing algorithms to highlight their differences and similarity needs to be studied. Apart from knowing the similarity and difference in search mechanisms of these algorithms it will also help to set criteria on when to use these algorithms. In this paper a comparative study of prey predator algorithm and firefly algorithm will be discussed. The discussion will also be supported by simulation results on selected twenty benchmark problems with different properties. A statistical analysis called Mann—Whitney U 2 test is used to compare the algorithms. The theoretical as well as simulation results support that prey predator algorithm is a more generalized search algorithm, whereas firefly algorithm falls as a special case of prey predator algorithm by fixing some of the parameters of prey predator algorithm to certain values.     

A new effective operator for the hybrid algorithm for solving global optimisation problems

Hybrid algorithms have been recently used to solve complex single-objective optimisation problems. The ultimate goal is to find an optimised global solution by using these algorithms. Based on the existing algorithms (HP_CRO, PSO, RCCRO), this study proposes a new hybrid algorithm called MPC (Mean-PSO-CRO), which utilises a new Mean-Search Operator. By employing this new operator, the proposed algorithm improves the search ability on areas of the solution space that the other operators of previous algorithms do not explore. Specifically, the Mean-Search Operator helps find the better solutions in comparison with other algorithms. Moreover, the authors have proposed two parameters for balancing local and global search and between various types of local search, as well. In addition, three versions of this operator, which use different constraints, are introduced. The experimental results on 23 benchmark functions, which are used in previous works, show that our framework can find better optimal or close-to-optimal solutions with faster convergence speed for most of the benchmark functions, especially the high-dimensional functions. Thus, the proposed algorithm is more effective in solving single-objective optimisation problems than the other existing algorithms.     

The improvement of glowworm swarm optimization for continuous optimization problems

Glowworm swarm optimization (GSO) algorithm is the one of the newest nature inspired heuristics for optimization problems. In order to enhances accuracy and convergence rate of the GSO, two strategies about the movement phase of GSO are proposed. One is the greedy acceptance criteria for the glowworms update their position one-dimension by one-dimension. The other is the new movement formulas which are inspired by artificial bee colony algorithm (ABC) and particle swarm optimization (PSO). To compare and analyze the performance of our proposed improvement GSO, a number of experiments are carried out on a set of well-known benchmark global optimization problems. The effects of the parameters about the improvement algorithms are discussed by uniform design experiment. Numerical results reveal that the proposed algorithms can find better solutions when compared to classical GSO and other heuristic algorithms and are powerful search algorithms for various global optimization problems.     

An effective hybrid particle swarm optimization algorithm for multi-objective flexible job-shop scheduling problem

Flexible job-shop scheduling problem (FJSP) is an extension of the classical job-shop scheduling problem. Although the traditional optimization algorithms could obtain preferable results in solving the mono-objective FJSP. However, they are very difficult to solve multi-objective FJSP very well. In this paper, a particle swarm optimization (PSO) algorithm and a tabu search (TS) algorithm are combined to solve the multi-objective FJSP with several conflicting and incommensurable objectives. PSO which integrates local search and global search scheme possesses high search efficiency. And, TS is a meta-heuristic which is designed for finding a near optimal solution of combinatorial optimization problems. Through reasonably hybridizing the two optimization algorithms, an effective hybrid approach for the multi-objective FJSP has been proposed. The computational results have proved that the proposed hybrid algorithm is an efficient and effective approach to solve the multi-objective FJSP, especially for the problems on a large scale.     

由单幅二维灰度图像重构物体表面形状*

鉴于目前很少有论文讨论完整的由单幅二维灰度图像重构物体表面形状的算法,包括它的控制参数的估计及算法的实现,介绍了一种完整的SFS算法.它在考虑自遮掩影响的情况下,有效地估计了SFS算法中涉及的各种控制参数,并引入亮度约束、灰度梯度约束和可积性约束,计算出表面高度和表面向量,实现三维重构.与传统的算法相比,本算法无论是在速度还是在精度方面都达到了比较高的水平,具有一定的应用前景.最后还指出了在MATLAB中实现需要注意的问题.     

基于种群关系的多种群粒子群协同优化算法

传统粒子群优化算法容易陷入局部最优解,搜索效率不高,针对此问题,提出了一种基于种群关系和斥力因子的多种群粒子群优化算法SRB-PSO (Swarm-Relation-Based PSO).根据当前搜索结果定义种群之间统治、对等和被统治3种关系,通过引入斥力因子来保证种群间搜索的多样性,并通过统治和被统治关系提高算法的搜索效率,从而在改善算法的全局搜索性能的同时提高解的质量.将算法与其他几种主流粒子群优化改进算法在标准测试集上进行对比,实验结果证明了SRB-PSO算法能较好地保持粒子多样性,全局搜索能力强,在解决多峰函数时的性能优于其他几种主流粒子群优化改进算法.     

A discrete version of particle swarm optimization for flowshop scheduling problems

Particle swarm optimization (PSO) is a novel metaheuristic inspired by the flocking behavior of birds. The applications of PSO to scheduling problems are extremely few. In this paper, we present a PSO algorithm, extended from discrete PSO, for flowshop scheduling. In the proposed algorithm, the particle and the velocity are redefined, and an efficient approach is developed to move a particle to the new sequence. To verify the proposed PSO algorithm, comparisons with a continuous PSO algorithm and two genetic algorithms are made. Computational results show that the proposed PSO algorithm is very competitive. Furthermore, we incorporate a local search scheme into the proposed algorithm, called PSO-LS. Computational results show that the local search can be really guided by PSO in our approach. Also, PSO-LS performs well in flowshop scheduling with total flow time criterion, but it requires more computation times.     

从阴影恢复形状的径向基函数反射模型研究

目的 为解决传统阴影恢复形状（SFS）算法由于光源方向初始信息估计不准确,恢复的物体表面过于光滑,3维表面形状误差较大等问题,建立了基于径向基函数神经网络的反射模型,并对传统的神经网络进行了改进。方法 建立的基于径向基函数（SFS）神经网络的从阴影恢复形状反射模型代替了传统方法中采用的理想朗伯体表面反射模型。该模型利用径向基函数优秀的局部映射和函数逼近能力来处理SFS问题,通过网络训练过程中的权值代替物体所受到的初始光源信息,解决了传统算法在进行计算时,必须已知光源参数的限制。在该网络模型中添加自适应学习率算法,加速网络的收敛和训练速度。结果 针对SFS问题处理的两幅经典合成图像以及两幅实际图像进行了实验,实验结果表明,改进后的算法在3维视觉效果和3维形状信息的恢复方面都明显优于传统算法。归一化后的3维高度误差结果相比传统算法缩小了60%以上,而且同时适用合成图像和实际图像;自适应学习率的加入,使得网络的训练速度大大加快,对一幅128×128像素的图像,运算速度提升了50%。结论 本文针对SFS问题建立了基于RBF神经网络的从阴影恢复形状反射模型,利用网络模型中的参数代替SFS问题中的初始光源信息,通过最优化方法求解SFS问题。并针对传统的神经网络固定学习率造成网络收敛速度慢,容易陷入局部极小值的问题,加入了自适应学习率算法。实验结果表明,改进后的算法在处理该SFS问题时表现了优秀的性能,适用范围更广,收敛速度更快。