一种非线性改变惯性权重的粒子群算法

引入递减指数和迭代阈值对基本粒子群算法中线性递减权策略进行了改进,在优化遮代过程中,惯性权重随当前迭代次数、指数递减率和迭代阚值非线性变化。对三种具有代表性的测试函数进行了仿真实验,并与基本粒子群算法以及其他改进的粒子群算法进行了比较,结果表明,文中所提的改进粒子群算法在搜优精度、收敛速度以度稳定性等方面有明显优势。     

复合策略惯性权重的粒子群优化算法

针对粒子群优化算法中典型线性递减策略的惯性权重不能和运算过程中非线性变化的特点相匹配的问题,提出一种用典型线性递减策略和动态变化策略相结合的方法来确定惯性权重的粒子群优化算法(L-DPSO)。该算法充分利用了线性递减策略的线性和动态变化策略的非线性特点,对两种策略赋予了相应的权重。然后将L-DPSO算法和单独使用典型线性递减策略来确定惯性权重的粒子群优化算法(LPSO)及单独使用动态变化策略来确定惯性权重的粒子群优化算法(DPSO)进行比较,用Griewank和Rastrigin函数进行测试,结果表明,适当调整典型线性递减策略和动态变化策略的权重,L-DPSO算法的收敛速度明显优于LPSO和DPSO算法,收敛精度也有所提高。最后,对L-DPSO算法和几种常用的惯性权重计算方法确定的粒子群优化算法作比较,用Griewank和Rastrigin函数进行测试,结果表明L-DPSO算法也有明显优势。     

基于高斯函数递减惯性权重的粒子群优化算法

为了有效地平衡粒子群优化算法的全局搜索和局部搜索能力,提出了一种基于高斯函数递减惯性权重的粒子群优化(GDIWPSO)算法。此算法利用高斯函数的分布性、局部性等特点,实现了对惯性权重的非线性调整。仿真过程中,首先对测试函数优化以确定惯性权重的递减方式;然后比较了该算法与权重线性递减、凸函数递减、凹函数递减的粒子群算法优化不同测试函数的性能;最后结果表明,提出的算法在搜索能力、收敛速度及执行效率等方面均有很大提高。     

基于禁忌搜索的自适应粒子群算法

针对惯性权重线性递减粒子群算法不能适应复杂的非线性优化搜索过程的问题,提出了一种基于Sigmoid函数和聚集距离变化率改变惯性权重的方法。为了解决算法后期易陷入局部最优的缺点,在算法后期引人了具有记忆能力的禁忌搜索算法。改进后的算法不仅综合了粒子群优化算法的快速性、随机性和全局收敛性的优点,而且还具有禁忌搜索局部寻优的能力。测试函数仿真结果表明,改进后的算法不仅较好地避免了陷入局部最优,而且收敛速度也有提高。     

基于禁忌搜索的自适应粒子群算法

针对惯性权重线性递减粒子群算法不能适应复杂的非线性优化搜索过程的问题,提出了一种基于Sigmoid函数和.聚集距离变化率改变惯性权重的方法.为了解决算法后期易陷入局部最优的缺点,在算法后期引入了具有记忆能力的禁忌搜索算法.改进后的算法不仅综合了粒子群优化算法的快速性、随机性和全局收敛性的优点,而且还具有禁忌搜索局部寻优的能力.测试函数仿真结果表明,改进后的算法不仅较好地避免了陷入局部最优,而且收敛速度也有提高.     

基于改进粒子群优化算法的火电厂机组负荷分配

以坑口电厂厂级监控信息系统的机组负荷在线优化分配功能模块为应用背景,针对模块所运用的基本粒子群优化算法在优化过程中容易陷入局部收敛、收敛速度慢的缺点,提出一种基于惯性权重非线性减小策略的改进粒子群优化算法,使惯性权重呈对数减小;测试函数仿真结果表明,改进粒子群优化算法在收敛速度和寻优精度方面,优化性能均优于基本粒子群优化算法;通过MATLAB与Visual C++混合编程,开发了机组负荷在线优化分配功能模块,提高了算法的计算效率和工程应用价值。     

基于Sigmoid惯性权值的自适应粒子群优化算法

针对粒子群优化算法存在的缺点,提出了基于Sigmoid惯性权值的自适应粒子群优化算法。一方面,引入粒子群早熟收敛的计算公式,以指导算法在进化过程中的具体执行策略,有效避免计算的盲目性,加快算法的收敛速度;另一方面,通过设定粒子群聚集程度的判定阈值,以使算法在线性递减惯性权值和基于Sigmoid函数思想的非线性递减惯性权值之间进行自适应地动态调整,从而有效减少了算法陷入局部最优的可能。测试函数仿真结果表明了该算法的可行性和有效性。     

直线二级倒立摆的一种稳定控制算法研究

针对线性二次型调节器(LQR)的权重矩阵Q和R的选取没有一个固定解析类方法，LQR的控制性能好坏基本取决于人工经验对Q和R的选取，若系统状态变量变多，调参就变得过于繁琐，以及基本粒子群算法(PSO)存在收敛速度慢，容易陷入局部最优等缺点，从惯性权重非线性动态调整，学习因子非线性动态调整以及基于自然选择机理三个角度来改进基本粒子群算法。并将改进粒子群算法应用于LQR参数优化，对直线二级倒立摆进行稳定控制。仿真结果表明，改进粒子群算法优化后的LQR相比一些传统的方法优化的LQR有着更好的控制效果。     

基于改进粒子群算法的BP算法的研究

针对BP算法的缺陷以及标准粒子群算法优化BP网络权值的不足,为了提高算法的全局搜索能力,提出了基于自适应动态调整惯性权重的粒子群算法的BP网络算法.算法根据适应度值的改变情况来调整惯性权重,使惯性权重的改变不依赖于最大迭代次数和当代迭代次数,从而使整个网络具有较快的收敛速度和较小的误差.将算法应用于海参疾病的诊断中.实验发现,基于自适应动态调整惯性权重的粒子群算法的BP算法比基本粒子群算法的BP算法收敛速度快,算法的准确率也比较高,同时改进算法训练的BP网络也比基本粒子群算法训练的BP网络稳定.仿真证明,自适应动态调整惯性权重的粒子群算法对BP算法的优化优于基本粒子群算法.     

改进粒子群优化算法在服务组合中的应用

针对标准粒子群优化(PSO)算法存在收敛速度慢、容易陷入局部最优的问题,提出一个改进的PSO算法,该算法设计一种新的惯性权重,在粒子搜索的不同阶段采用不同的计算公式计算惯性权重,并引入自适应变异策略和线性变化的学习因子。实验结果表明,该算法的收敛性等性能比基本粒子群算法有明显提高,能较好地解决非线性问题。     

惯性权值对粒子群算法收敛性的影响及改进

研究惯性权值对粒子群算法(PSO)收敛性的影响,在分析线性权值递减策略基础上,提出一种基于各粒子适应值的递减策略——FDIW。标准测试函数对比实验表明,该策略可以使粒子在搜索初期获得更好的多样性,从而使粒子具有更强的摆脱局部极值的能力,在搜索末期可以加快粒子收敛速度以提高PSO算法的性能。     

基于多微云协作的计算任务卸载

针对多微云计算模式下计算任务卸载过程复杂、任务响应时间长的问题,构建面向多微云协作的计算任务卸载模型,并提出加权自适应惯性权重的粒子群优化（WAIW-PSO）算法,快速求解最优卸载策略。首先,对移动终端-微云-远程云的任务执行过程进行建模;其次,考虑多用户对计算资源的竞争,构建基于多微云协作的任务卸载模型;最后,针对求解最佳任务卸载策略复杂度过高的情况,提出WAIW-PSO算法求解卸载问题。仿真实验结果表明,与标准粒子群优化（PSO）算法以及基于高斯函数递减惯性权重的粒子群优化（GDIWPSO）算法相比,WAIW-PSO算法可以根据进化代数和个体适应度综合调整惯性权重,寻优能力较强,求解最优卸载策略的时间最短;在不同设备数、任务数等情况下选择不同任务卸载策略进行对比实验的结果表明,基于WAIW-PSO算法的卸载策略可以明显缩短任务总完成时间。     

混沌惯性权值调整策略的粒子群优化算法

粒子群优化算法是一种新颖的智能优化算法。惯性权值对粒子群优化算法的性能有着重要的影响。在分析已有的惯性权值调整策略的基础上,提出了混沌惯性权值调整策略,该策略将惯性权值用一个混沌变量来描述。标准测试函数实验表明,在不影响优化结果精度的情况下,混沌惯性权值调整策略的粒子群优化算法收敛速度较已有方法有了明显的提高。     

Intelligent identification and control using improved fuzzy particle swarm optimization

This paper presents a novel improved fuzzy particle swarm optimization (IFPSO) algorithm to the intelligent identification and control of a dynamic system. The proposed algorithm estimates optimally the parameters of system and controller by minimizing the mean of squared errors. The particle swarm optimization is enhanced intelligently by using a fuzzy inertia weight to rationally balance the global and local exploitation abilities. In the proposed IFPSO, every particle dynamically adjusts inertia weight according to particles best memories using a nonlinear fuzzy model. As a result, the IFPSO algorithm has a faster convergence speed and a higher accuracy. The performance of IFPSO algorithm is compared with advanced algorithms such as Real-Coded Genetic Algorithm (RCGA), Linearly Decreasing Inertia Weight PSO (LDWPSO) and Fuzzy PSO (FPSO) in terms of parameter accuracy and convergence speed. Simulation results demonstrate the effectiveness of the proposed algorithm.     

粒距反馈的S函数粒子群权值调整策略

针对标准粒子群优化（PSO）算法把惯性权值作为全局参数,很难适应复杂的非线性优化的问题,提出了一种基于粒距和S型函数的粒子群权值调整策略（SFIW）。利用S型函数能够在非线性和线性之间平滑过渡的特性,构造了基于Logistic方程的惯性权值函数。在优化过程中根据每个粒子的粒距大小,调整每个粒子的惯性权值函数的非线性系数,使得粒距较大的粒子获得较大的惯性权值、粒距较小的粒子获得较小的惯性权值,从而平衡算法的局部开发和全局探测能力。最后,通过对基准函数的仿真并与其他PSO算法比较,验证了算法的有效性和可行性。     

Parameter estimation of bilinear systems based on an adaptive particle swarm optimization

Bilinear models can approximate a large class of nonlinear systems adequately and usually with considerable parsimony in the number of coefficients required. This paper presents the application of Particle Swarm Optimization (PSO) algorithm to solve both offline and online parameter estimation problem for bilinear systems. First, an Adaptive Particle Swarm Optimization (APSO) is proposed to increase the convergence speed and accuracy of the basic particle swarm optimization to save tremendous computation time. An illustrative example for the modeling of bilinear systems is provided to confirm the validity, as compared with the Genetic Algorithm (GA), Linearly Decreasing Inertia Weight PSO (LDW-PSO), Nonlinear Inertia Weight PSO (NDW-PSO) and Dynamic Inertia Weight PSO (DIW-PSO) in terms of parameter accuracy and convergence speed. Second, APSO is also improved to detect and determine varying parameters. In this case, a sentry particle is introduced to detect any changes in system parameters. Simulation results confirm that the proposed algorithm is a good promising particle swarm optimization algorithm for online parameter estimation.     

混合变异算子的自适应粒子群优化算法

针对惯性权重线性递减粒子群算法(LDW)不能适应复杂的非线性优化搜索过程的问题,提出了一种非线性递减的惯性权重策略,使算法很快地进入局部搜索,并在算法中引入混合变异算子,克服算法易早熟收敛的缺陷。对几种典型函数的测试结果表明,本文算法的收敛速度和收敛精度都明显优于LDW算法。     

粒子群优化算法中惯性权重的研究进展

粒子群优化算法是根据鸟群觅食过程中的迁徙和群集模型而提出的用于解决优化问题的一类新兴的随机优化算法。惯性权重是粒子群算法中非常重要的参数,可以用来控制算法的开发和探索能力。简单介绍了标准粒子群优化算法的基本原理,全面综述了现有文献中对惯性权重的研究进展情况。     

A novel stability-based adaptive inertia weight for particle swarm optimization

Particle swarm optimization (PSO) is a stochastic population-based algorithm motivated by intelligent collective behavior of birds. The performance of the PSO algorithm highly depends on choosing appropriate parameters. Inertia weight is a parameter of this algorithm which was first proposed by Shi and Eberhart to bring about a balance between the exploration and exploitation characteristics of PSO. This paper presents an adaptive approach which determines the inertia weight in different dimensions for each particle, based on its performance and distance from its best position. Each particle will then have different roles in different dimensions of the search environment. By considering the stability condition and an adaptive inertia weight, the acceleration parameters of PSO are adaptively determined. The corresponding approach is called stability-based adaptive inertia weight (SAIW). The proposed method and some other models for adjusting the inertia weight are evaluated and compared. The efficiency of SAIW is validated on 22 static test problems, moving peaks benchmarks (MPB) and a real-world problem for a radar system design. Experimental results indicate that the proposed model greatly improves the PSO performance in terms of the solution quality as well as convergence speed in static and dynamic environments.     

An improved particle swarm optimiser based on swarm success rate for global optimisation problems

Inertia weight is one of the control parameters that influences the performance of particle swarm optimisation (PSO) in the course of solving global optimisation problems, by striking a balance between exploration and exploitation. Among many inertia weight strategies that have been proposed in literature are chaotic descending inertia weight (CDIW) and chaotic random inertia weight (CRIW). These two strategies have been claimed to perform better than linear descending inertia weight (LDIW) and random inertia weight (RIW). Despite these successes, a closer look at their results reveals that the common problem of premature convergence associated with PSO algorithm still lingers. Motivated by the better performances of CDIW and CRIW, this paper proposed two new inertia weight strategies namely: swarm success rate descending inertia weight (SSRDIW) and swarm success rate random inertia weight (SSRRIW). These two strategies use swarm success rates as a feedback parameter. Efforts were made using the proposed inertia weight strategies with PSO to further improve the effectiveness of the algorithm in terms of convergence speed, global search ability and improved solution accuracy. The proposed PSO variants, SSRDIW_PSO and SSRRIW_PSO were validated using several benchmark unconstrained global optimisation test problems and their performances compared with LDIW-PSO, CDIW-PSO, RIW-PSO, CRIW-PSO and some other existing PSO variants. Empirical results showed that the proposed variants are more efficient.