基于GA-PSO融合算法的二自由度PID参数优化

在工业过程控制中,PID参数调节直接影响工业生产的质量和效率。针对PID参数调节难这一问题,文中提出了一种将遗传算法和粒子群算法相结合的智能融合算法,并将该算法应用于二自由度PID参数的优化中。该算法在遗传算法的变异算子中引入粒子群算法,充分发挥两种单一智能算法的优点,并弥补了两者的缺点。算例仿真验证结果显示,该算法可以很好的应用于PID参数优化,且在调节PID参数的过程中具有优良的性能指标数值,在目标值跟踪特性和外扰动抑制特性上具有更好的控制效果。     

基于萤火虫算法的PID参数优化方法研究

针对传统的PID参数整定方法越来越费时且难以满足控制要求的问题,提出一种采用萤火虫算法来优化PID控制参数的方法,设计了基于Simulink的参数优化模型,并进行仿真计算。结果表明,利用萤火虫算法优化PID控制器参数的阶跃响应响应时间短,基本没有超调,跟踪过程较平稳,仿真结果证明将萤火虫算法应用于PID参数优化是切实可行的。     

基于粒子群算法的PID控制器研究与应用

通过建立粒子群优化的PID控制器参数模型,在控制过程中将PID参数(比例、积分、微分)作为粒子群中的粒子,采用控制误差绝对值时间积分函数作为优化目标,在控制过程中动态调整PID的三个控制参数,从而进行PID控制参数的实时优化,最后将优化方案应用于中央空调温度控制系统.仿真应用研究表明,PID参数优化策略具有很强的灵活性、适应性和鲁棒性,进而验证了优化方案的可行性和有效性.     

自适应权重混合粒子群算法在PID整定中的应用

传统工业控制中的PID参数整定需要良好的先验知识才能达到较好的整定效果,这种人工经验整定PID参数的方法耗时耗力、精度低且鲁棒性差.针对PID参数整定难的问题,标准粒子群优化算法可以实现对PID参数的快速整定,但其易陷入局部极值.因此,本文对标准PSO算法进行改进,将自适应权重混合粒子群优化算法应用于PID参数整定中....     

基才PSO—BP神经网络的PID控制器参数优化方法

针对传统PID控制系统参数整定过程存在的在线整定困难和控制品质不理想等问题,结合BP神经网络自学习和自适应能力强等特点,提出采用BP神经网络优化PID控制器参数。其次,为了加快BP神经网络学习收敛速度,防止其陷入局部极小点,提出采用粒子群优化算法来优化BP神经网络的连接权值矩阵。最后,给出了PSO—BP算法整定优化PID控制器参数的详细步骤和流程图。并通过一个PID控制系统的仿真实例来验证本文所提算法的有效性。仿真结果证明了本文所提方法在控制品质方面优于其它三种常规整定方法。     

蚁群算法在PID控制中的应用及其参数影响

鉴于传统PID参数整定方法的不足,提出了一种采用蚁群算法优化选取PID控制参数的方法。通过建立数学模型将PID控制参数选择问题抽象成路径选择问题,从而将蚁群算法成功的应用于PID参数优选,并对寻优过程进行了仿真。将结果与常用的临界比例度法整定的结果进行了比较,发现基于蚁群算法的PID参数优选方案可使系统超调量大幅减小,并明显缩短系统调节时间,具有良好的应用前景。此外,讨论了蚁群算法中的关键参数对算法性能的影响,对比了不同参数下算法的收敛速度和求解质量。     

一种改进的RBF整定PID及其仿真实现

文中在分析RBF神经网络整定PID算法优缺点的基础上,给出了一种采用遗传模拟退火算法来优化网络结构和权值参数的RBF神经网络,将改进的RBF神经网络用于整定PID控制,并给出了相应的仿真测试例子。仿真实验结果表明,与采用梯度法优化网络权值等参数的RBF神经网络相比,给出的优化算法能更好地辨识控制系统,具有通用性好、调节精度高、在抑制超调量能力强等优点。     

改进粒子群算法在四旋翼PID参数优化中的应用

采用试凑方式对四旋翼飞行器PID控制参数人工进行调整工作量大、费时且难以达到较好的控制效果。为了解决控制参数优化问题,提出基于带交叉因子的粒子群算法(PSO)的PID参数优化策略。将带交叉因子的粒子群算法能快速准确找到最优参数解的特点与PID控制结合起来,在控制过程中将PID参数作为粒子群中的粒子,用遗传算法对粒子进行选择、保优、交叉,以ITAE准则作为误差性能指标,用粒子群算法调整PID参数,得出最优的粒子作为四旋翼飞行器的PID控制器参数。仿真结果显示,该方法具有更强的灵活性、适应性和鲁棒性,并能提高控制系统的精度,具有很好的工程应用价值。     

基于RBF神经网络的永磁同步伺服电机控制系统

针对永磁同步电机控制系统,建立其磁场定向控制数学模型。运用增量式数字PID的方法实现对PMSM的传统PID控制策略。在此基础上,借助RBF神经网络的学习能力,进行PID控制器参数的自适应整定,进一步改善PID控制器的性能。同时,为提高RBF网络性能,采用粒子群算法对网络进行优化。仿真表明,与传统PID控制比较,基于RBF的PID控制系统能提高PID控制器的性能,改善了PMSM控制系统的收敛速度和跟踪精度。     

利用粒子群算法实现陀螺仪耦合系统动态响应优化

利用平均法分析半球陀螺仪控制系统,得到通过PID模块实现的深度负反馈控制回路设计。根据大机动平台等对陀螺仪系统对快速响应的要求,寻求方法对深度负反馈控制的PID参数整定以实现输出动态优化。系统中的耦合项存在是控制参数设计的难点。通过参数变换和输出结果分析,发现系统PID参数与系统动态响应表现之间没有明显的相关性,不能通过拟合方式去实现优化。将系统的耦合关系去除,通过以往设计带宽的方式得到了系统的优化参数。利用ITAE评价标准作为适应度函数,得到利用粒子群算法（PSO算法）优化后的控制系统,通过比对两者的系统带宽和ITAE输出,在带宽近似的情况下,PSO优化比传统去耦合优化的ITAE标准由49.8下降到了0.36,调节时间由1.049s下降到了0.0905s,大大优化了系统的输出的动态响应。     

Adaptive subcarrier and bit allocation based on ant colony optimization

The problem of resource allocation in multiuser orthogonal frequency division multiplexing (OFDM) system is a combinatorial optimization problem, difficult to obtain optimal solutions in polynomial time. For the sake of reducing complexity, it can be solved either by relaxing constraints and making use of linear algorithms or by metaheuristic methods. In this paper, an algorithm based on ant colony optimization (ACO), which is a typical algorithm of metaheuristic methods, is proposed for the problem, utilizing excellent search performance of ACO to obtain good solutions. In addition, a parameter is applied to balance the efficiency and fairness of resource allocation. Performance analysis between algorithms based on ACO and genetic algorithm (GA) is carried out, indicating that the proposed algorithm based on ACO outperforms traditional linear algorithms as well as GA in the system throughput with assurance of fairness simultaneously, being as a promising technology for OFDM resource allocation.     

遗传算法在半导体器件参数提取软件中的实现

随着半导体器件参数的增加,目标函数的自变量空间维数变得越来越大。传统的优化算法已经不能很好地处理此类问题,主要表现在无法有效地达到目标函数的极小点。文章首先在参数提取软件中实现了遗传算法,并与传统的优化算法进行了比较,探讨了该算法在参数提取软件中的实用性,提出了将遗传算法与传统优化算法结合在一起的方法。     

免疫遗传算法及认知无线电参数优化决策

根据感知的频谱环境变化及时优化并调整无线电参数是认知无线电的关键技术之一,也是一个复杂的非线性多目标优化决策问题。遗传算法是最适合优化问题的,但当遗传算法应用于优化问题时存在过早收敛问题。提出了基于遗传算法和人工免疫系统相结合的免疫遗传算法（IGA）来克服以上问题。由于在GA算法中引入了免疫系统中抗体和抗原的概念并在每一次迭代中丢弃亲和力较大的抗体,有效地防止了GA中过早收敛现象。最后,用免疫遗传算法来解决认知无线电的参数优化问题。仿真结果表明,免疫遗传算法可以迅速达到最优决策。     

基于截短ARQ协议的协作分集系统吞吐量研究

研究协作分集通信系统的跨层设计使系统吞吐量最大化.首先推导基于截短ARQ协议的协作分集和两跳系统的吞吐量理论表达式,揭示数据包长度和调制方式对系统吞吐量的影响,在此基础上用自适应技术优化系统性能,采用连续二维优化求出了吞吐量的最大值,进而提出了实用的二维离散吞吐量优化算法,该算法的优化结果与吞吐量最大值相差很小,最后提出了计算量更小的一维离散优化算法,且其吞吐量性能损失也很小.     

Survey of research on application of heuristic algorithm in machine learning

Aiming at the problems existing in the application of machine learning algorithm,an optimization system of the machine learning model based on the heuristic algorithm was constructed.Firstly,the existing types of heuristic algorithms and the modeling process of heuristic algorithms were introduced.Then,the advantages of the heuristic algorithm were illustrated from its applications in machine learning,including the parameter and structure optimization of neural network and other machine learning algorithms,feature optimization,ensemble pruning,prototype optimization,weighted voting ensemble and kernel function learning.Finally,the heuristic algorithms and their development directions in the field of machine learning were given according to the actual needs.     

New method of traffic flow forecasting based on quantum particle swarm optimization strategy for intelligent transportation system

Traffic flow forecasting is one of the essential means to realize smart cities and smart transportation. The accurate and effective prediction will provide an important basis for decision‐making in smart transportation systems. This paper proposes a new method of traffic flow forecasting based on quantum particle swarm optimization (QPSO) strategy for intelligent transportation system (ITS). We establish a corresponding model based on the characteristics of the traffic flow data. The genetic simulated annealing algorithm is applied to the quantum particle swarm algorithm to obtain the optimized initial cluster center, and is applied to the parameter optimization of the radial basis neural network prediction model. The function approximation of radial basis neural network is used to obtain the required data. In addition, in order to compare the performance of the algorithms, a comparison study with other related algorithms such as QPSO radial basis function (QPSO‐RBF) is also performed. Simulation results show that compared with other algorithms, the proposed algorithm can reduce prediction errors and get better and more stable prediction results.     

手征媒质反射特性仿真计算

手征媒质是双各向同性媒质的一种,其手征参数具有可调性。首先,在标准粒子群 算法(PSO)和模拟退火（SA）算法的基础上进行了改进,并利用混合算法优化设计手征参数 及媒质 厚度,以在给定的频率范围内获得较高的吸收率。然后,仿真计算了某一个参数取不同值而 其它参数固定情况下电磁波垂直入射到手征媒质时的反射系数。结果证明,只有在最优化参 数条件下才可以在频带内获得较理想的吸收率和反射系数。     

Formulation of the drift reliability optimization problem

Drift Reliabilty (DR) of a system is related to that part of the overal system reliability that is concerned with the system element ageing and parameter dependence on such environmental conditions as temperature, level of radiation, humidity, etc. Its maximization during the system design phase is of great economic importance for the manufacturers of electronic products and other equipment. In this paper the DR optimization problem is mathematically formulated in the context of parametric manufacturing yield optimization, and some algorithmic aspects of its solution are discussed. It is shown that it is possible to formulate the problem in such a way that some measures of both the yield and the average time to failure (due to the system element drift) can be maximized, and different trade-off situations investigated. The existing efficient gradient based yield optimization algorithms can be used after only some relatively simple modifications of the gradient estimation formulas.     

Extraction of Passive Device Model Parameters Using Genetic Algorithms

The extraction of model parameters for embedded passive components is crucial for designing and characterizing the performance of multichip module (MCM) substrates. In this paper, a method for optimizing the extraction of these parameters using genetic algorithms is presented. The results of this method are compared with optimization using the Levenberg‐Marquardt (LM) algorithm used in the HSPICE circuit modeling tool. A set of integrated resistor structures are fabricated, and their scattering parameters are measured for a range of frequencies from 45 MHz to 5 GHz. Optimal equivalent circuit models for these structures are derived from the s‐parameter measurements using each algorithm. Predicted s‐parameters for the optimized equivalent circuit are then obtained from HSPICE. The difference between the measured and predicted s‐parameters in the frequency range of interest is used as a measure of the accuracy of the two optimization algorithms. It is determined that the LM method is extremely dependent upon the initial starting point of the parameter search and is thus prone to become trapped in local minima. This drawback is alleviated and the accuracy of the parameter values obtained is improved using genetic algorithms.     

基于区间全局优化的非线性最小二乘估计

分析了使用区间全局优化算法进行非线性系统模型参数估计的原因,介绍了非线性最小二乘估计和区间全局优化算法.在非线性系统模型参数估计中,相对于通过优化目标函数求得待估参数点估计的现有算法,基于区间分析的区间全局优化算法不仅可以求得待估参数的点估计,还可得到肯定包含待估参数真值的估计区间,并且该算法还具有计算结果稳定以及更大范围收敛的性质.通过仿真实验并与其他方法进行比较,结果表明算法的可行性和有效性.