基于改进微粒群神经网络的油料储备预测

根据油料储备历史数据样本进行油料储备预测,是实施油料保障有效举措.油料储备预测是具有不确定性、突变性的多变量复杂系统,预测难度大.为了解决采用传统预测法所存在的局限性,将微粒群优化算法与神经网络相融合,提出了改进微粒群神经网络的油料储备预测模型.利用神经网络自学习能力,捕捉预测系统非线性关系.将神经网络参数映射为实数码微粒,构造复合适应度函数.引入微粒距离系数,动态调整微粒速度和位置进化参数.借助微粒群优化算法较强全局搜索能力,训练神经网络参数,优化其结构,消除神经网络训练收敛慢、易陷入局部极值等现象.仿真实例表明,改进模型预测精确性评价指标良好,建模复杂度较低.     

基于高斯微粒群优化的动态神经网络延迟系统辨识

为提高神经网络对未知非线性大滞后动态系统的泛化能力,提出一种基于高斯微粒群优化的自适应动态前馈神经网络.在输入层与隐含层之间、隐含层与输出层之间分别加入动态延迟算子,可以高效地辨识出系统纯滞后时间,建立精确系统模型.此外,采用高斯函数和混沌映射方法平衡微粒群算法全局寻优能力,以克服提前收敛的缺陷,从而快速有效地自适应优化网络中的参数.仿真实验表明了该方法在非线性人滞后系统辨识中的有效性.     

模拟退火PSO的神经网络的网络流量预测模型

为解决网络流量时间序列的预测问题,针对传统BP神经网络的网络流量时间序列预测模型容易陷入局部极小值的不足,提出一种基于模拟退火的微粒群算法训练神经网络的网络流量时间序列预测模型.将模拟退火算法和基本粒子微粒群算法相结合,设计出一种基于模拟退火的微粒群算法.利用基于模拟退火微粒群算法优化BP神经网络的权值和阀值,对实际采集的网络流量时间序列进行建模.实验结果表明,基于模拟退火的微粒群算法训练的神经网络具有较高的预测效果,相对于传统的神经网络模型具有更高的预测精度和良好的自适应性.     

基于模拟退火PSO的神经网络模型

人工神经网络的训练问题实质上是一个优化问题。将模拟退火算法和基本粒子微粒群算法相结合,提出一种基于模拟退火的微粒群算法,该算法能够有效抑制早熟收敛。利用基于模拟退火微粒群算法优化BP神经网络的权值和阀值,有效的解决了BP算法易陷入局部极小值的缺点,从而提高了神经网络的精度和收敛速度。通过对非线性系统进行Matlab仿真研究,实验结果表明,基于模拟退火的微粒群算法训练的神经网络是一种有效的辨识方法。     

基于动态邻域微粒群的Smith预估双控制器设计

针对模型未知时滞系统的预测补偿控制,提出一种基于动态邻域拓扑微粒群算法以优化动态神经网络的参数,并将其作为预估器和辨识器应用于一种新的Smith预估双控制器结构设计.利用微粒群算法空间搜索能力指标,动态建立邻域拓扑结构,优化神经网络参数,并将两者的组合模型应用于新的双控制器结构,将负载扰动和定值控制分开,以提高Smith预测补偿模型的控制精度和鲁棒性,最后通过仿真验证了所提出方法的有效性.     

基于NN改进PSO算法的机器人路径规划

本文介绍了基于神经网络和微粒群优化算法的移动机器人动态避障路径规划算法.通过神经网络改进的微粒群算法,充分利用了神经网络的融合性和并行性来提高微粒群算法中适应度函数的准确性.通过神经网络描述机器人工作空间的动态环境约束并找到最优的适应度函数,在微粒群算法中使用该函数,求得微粒群算法最优无碰路径.     

梯度微粒群优化算法及其收敛性分析

针对标准微粒群优化算法微粒运动轨迹的收敛性进行了分析.给出并证明了微粒运动轨迹收敛的充分条件.提出一种简便的等高线图判别法,该方法能够通过参数的位置判断微粒轨迹是否收敛并衡量收敛速度.为提高算法的收敛速度.构造出一种梯度微粒群优化算法,给出并证明了该方法收敛的充分条件.仿真结果表明,梯度微粒群优化算法具有优良的搜索性能.     

改进协同微粒群优化的模糊神经网络控制系统设计

针对协同微粒群算法不能保证收敛到局部或全局最优值的问题,提出一种改进协同微粒群算法(ICPSO),并证明了该算法能以概率1收敛干全局最优解.应用ICPSO建立一类非线性对象的神经网络辨识模型,并对系统的模糊神经网络自适应控制器的参数进行了离线和在线优化.仿真结果表明,ICPSO能提高系统的建模精度,增强模型的泛化能力,而且由ICPSO训练的控制器可以达到良好的控制效果.     

惯性权重粒子群算法模型收敛性分析及参数选择

为提高粒子群算法的收敛性,基于动力系统的稳定性理论分析了带有惯性权重的粒子群算法模型的收敛性,提出了在算法模型收敛条件下惯性权重w和加速系数c的参数约束关系.使用4个测试函数对具有所提参数约束关系的惯性权重粒子群算法模型和典型参数取值惯性权重粒子群算法模型进行了对比仿真研究,实验结果表明,具有提出的参数约束关系的惯性权重粒子群算法模型在收敛性方面具有显著优越性.     

基于部分微粒更新改进的具有非线性动态惯性因子的微粒群新算法

微粒群算法是基于群体智能的全局优化算法,在许多领域得到广泛的应用.该算法具有简单易于实现的优点,但是容易陷入局部极值尤其是采用动态惯性因子.采用动态惯性因子有利于提高微粒群算法的收敛速度,但降低了其全局搜索能力.针对具有惯性因子微粒群算法在进化过程中微粒群多样性减弱容易陷入局部最优值的问题,以非线性动态惯性因子的微粒群算法为基础,提出1种基于部分微粒更新的微粒群算法,以提高微粒群的多样性,进而提高了算法的全局搜索能力.新算法利用Sphere、Rastrigin、Rosenbrock、Schaffer、Freudenstein-Roth、Goldstern-Price 6个经典测试函数进行测试,并与基本微粒群算法和具有线性动态惯性因子微粒群算法比较.通过模拟优化比较,新算法寻优效率高、全局性能好、优化结果稳定,新算法能有效提高微粒群的多样性,具有较好的收敛性能和全局优化能力,尤其适合多峰函数的优化.     

一种非线性动态自适应的Agent联盟生产算法

代理(Agent)联盟是对无线传感器网络WSN(Wireless Sensor Network)进行管理的重要手段.引入粒子群算法PSO(Particle Swarm Optimization)并对其进行改进,使PSO的参数具有非线性动态自适应性.将改进的PSO用于求解Agent联盟生成问题,并针对WSN的特性设计了一种效益函数用于评价联盟的效益.采用基于非线性动态自适应PSO的Agent联盟生成算法,在联盟生成初期搜索范围较广,搜索后期在局部挖掘上表现出良好的性能.实验证明在解决Agent联盟生成问题中,基于PSO的算法在稳定性上优于其他算法,基于改进PSO的联盟生成算法可以加大搜索空间,更快的收敛到最优解,且该算法可以同时生成多个Agent联盟,支持并行多任务环境下的Agent联盟求解.     

Training Reformulated Radial Basis Function Neural Networks Capable of Identifying Uncertainty in Data Classification

This paper introduces a learning algorithm that can be used for training reformulated radial basis function neural networks (RBFNNs) capable of identifying uncertainty in data classification. This learning algorithm trains a special class of reformulated RBFNNs, known as cosine RBFNNs, by updating selected adjustable parameters to minimize the class-conditional variances at the outputs of their radial basis functions (RBFs). The experiments verify that quantum neural networks (QNNs) and cosine RBFNNs trained by the proposed learning algorithm are capable of identifying uncertainty in data classification, a property that is not shared by cosine RBFNNs trained by the original learning algorithm and conventional feed-forward neural networks (FFNNs). Finally, this study leads to a simple classification strategy that can be used to improve the classification accuracy of QNNs and cosine RBFNNs by rejecting ambiguous feature vectors based on their responses.     

基于最小不确定性神经网络的茶味觉信号识别

提出了一种基于最小不确定性神经网络方法的味觉信号识别模型,使用贝叶斯概率理论和粒子群优化算法(PSO),快速而有效地确定网络结构参数,实现了对10种茶味觉信号的识别,实验结果表明了将该模型引入到茶味觉信号识别的可行性和有效性。     

Stability Analysis and the Stabilization of a Class of Discrete-Time Dynamic Neural Networks

This paper deals with problems of stability and the stabilization of discrete-time neural networks. Neural structures under consideration belong to the class of the so-called locally recurrent globally feedforward networks. The single processing unit possesses dynamic behavior. It is realized by introducing into the neuron structure a linear dynamic system in the form of an infinite impulse response filter. In this way, a dynamic neural network is obtained. It is well known that the crucial problem with neural networks of the dynamic type is stability as well as stabilization in learning problems. The paper formulates stability conditions for the analyzed class of neural networks. Moreover, a stabilization problem is defined and solved as a constrained optimization task. In order to tackle this problem two methods are proposed. The first one is based on a gradient projection (GP) and the second one on a minimum distance projection (MDP). It is worth noting that these methods can be easily introduced into the existing learning algorithm as an additional step, and suitable convergence conditions can be developed for them. The efficiency and usefulness of the proposed approaches are justified by using a number of experiments including numerical complexity analysis, stabilization effectiveness, and the identification of an industrial process     

Use of particle swarm optimization for machinery fault detection

A study is presented on the application of particle swarm optimization (PSO) combined with other computational intelligence (CI) techniques for bearing fault detection in machines. The performance of two CI based classifiers, namely, artificial neural networks (ANNs) and support vector machines (SVMs) are compared. The time domain vibration signals of a rotating machine with normal and defective bearings are processed for feature extraction. The extracted features from original and preprocessed signals are used as inputs to the classifiers for detection of machine condition. The classifier parameters, e.g., the number of nodes in the hidden layer for ANNs and the kernel parameters for SVMs are selected along with input features using PSO algorithms. The classifiers are trained with a subset of the experimental data for known machine conditions and are tested using the remaining set of data. The procedure is illustrated using the experimental vibration data of a rotating machine. The roles of the number of features, PSO parameters and CI classifiers on the detection success are investigated. Results are compared with other techniques such as genetic algorithm (GA) and principal component analysis (PCA). The PSO based approach gave a test classification success rate of 98.6–100% which were comparable with GA and much better than with PCA. The results show the effectiveness of the selected features and the classifiers in the detection of the machine condition.     

Improving the effect of fuzzy clustering on RBF network’s performance in terms of particle swarm optimization

This paper proposes a novel training algorithm for radial basis function neural networks based on fuzzy clustering and particle swarm optimization. So far, fuzzy clustering has proven to be a very efficient tool in designing such kind of networks. The motivation of the current work is to quantify the exact effect of fuzzy cluster analysis on the network’s performance and use it in order to substantially improve this performance. There are two key theoretical findings resulting from the present work. First, it is analytically proved that when the standard fuzzy c-means algorithm is used to generate the input space fuzzy partition, the main effect this partition imposes to the network’s square error (i.e. performance index) can be written down in terms of a distortion function that measures the ability of the partition to recreate the original data. Second, using the aforementioned distortion function, an upper bound of the network’s square error can be constructed. Then, the particle swarm optimization (PSO) is put in place to minimize the above upper bound and determine the network’s parameters. To further improve the accuracy, the basis function widths and the connection weights are fine-tuned by employing a steepest descent approach. The main experimental findings are: (a) the implementation of the PSO obtains a significant reduction of the square error while exhibiting a smooth dynamic behavior, (b) although the steepest descent further decreases the error it finally obtains smaller reduction rates, meaning that the strongest impact on the error reduction is provided by the PSO, and (c) the improved performance of the proposed network is demonstrated through an extensive comparison with other related methods using a 10-fold cross-validation analysis.     

Adaptive Control of Discrete-time Nonlinear Systems Using ITF-ORVFL

Random vector functional ink(RVFL) networks belong to a class of single hidden layer neural networks in which some parameters are randomly selected. Their network structure in which contains the direct links between inputs and outputs is unique, and stability analysis and real-time performance are two difficulties of the control systems based on neural networks. In this paper, combining the advantages of RVFL and the ideas of online sequential extreme learning machine(OS-ELM) and initial-trainin...     

基于PNDSC 的欠驱动AUV编队控制器设计

针对含有模型不确定与未知海洋环境扰动下的欠驱动自主水下航行器(AUV)的编队控制问题, 提出一种基于预估器的神经网络动态面(PNDSC) 控制算法. 将动态面法引入控制器的设计中, 采用神经网络逼近AUV模型中的不确定项与海洋环境的扰动, 并结合预估器设计了神经网络权值的离散迭代更新率. Lyapunov 稳定性分析表明, 闭环系统所有信号是一致最终有界的. 仿真结果验证了所提出方法的有效性.

     

欠驱动AUV模糊神经网络L2增益鲁棒跟踪控制

提出基于模糊神经网络欠驱动水下自主机器人(AUV)的L2增益鲁棒跟踪控制方法,该方法通过在线学习逼近动力学模型的不确定项.控制器克服了由于缺少横向推力对跟踪误差的影响,在考虑未知海流干扰情况下,实现了系统对模糊神经网络逼近误差的L2增益小于γ.利用Lyapunov稳定性理论证明了闭环控制系统误差信号一致最终有界.最后,通过精确模型参数和参数扰动仿真实验验证了该控制方法具有很好的跟踪效果和较强的鲁棒性.