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1.
织物染色计算机配色的数值分析方法   总被引:1,自引:0,他引:1       下载免费PDF全文
讨论将数值分析的方法引入到织物染色的计算机配色过程中,以解决织物染色配色过程中存在的不确定性和非线性问题。建立基于单色小样值和三拼色小样值与其相应浓度的数学模型,通过数据拟合并使用Newton—Krylov算法,实现染料浓度的求解。实验数据证明该方法精确度较高、计算简单并达到了预期的效果。  相似文献   

2.
针对织物染色配色过程中的复杂性和非线性问题,提出一种基于聚类的BP神经网络织物染色配色方法.通过模糊C均值聚类方法对初始样本集进行预处理,然后构建结构合理的BP神经网络对处理后的样本集进行训练和仿真.实验结果验证该方法与传统的BP神经网络相比能明显提高网络的收敛速度和泛化能力,能较准确地实现对织物染色配方的预测.  相似文献   

3.
本文从对Kubelka-Munk理论的分析入手,通过对三刺激值模式和全光谱配色模式的深入研究,指出了这两种模式存在的优缺点,并在此基础上提出了利用BP神经网络进行计算机染色配色的算法,最后按照此算法进行了织物染色的计算机配色实验,验证了人工神经网络算法在织物染色配色中应用的可能性和可靠性。  相似文献   

4.
针对一个375 MW热电厂的锅炉-汽轮机系统仿真模型,采用多层前向神经网络进行离线建模;讨论了网络结构设计、训练算法等神经网络建模问题;采用相同的固定负荷数据分别建立了线性ARX模型和局部神经网络模型并做多步预测比较;通过对基于一层隐层的全局神经网络模型的训练和仿真,结果证实了神经网络在非线性系统建模和辨识上的有效性.  相似文献   

5.
针对目前人工配色受配色者的生理、心理等主观因素影响,使产品质量难以保证这一问题,提出了基于径向基函数(RBF)神经网络的计算机柔印配色方法。该方法通过印刷实验获得样本数据,利用K均值聚类算法确定隐含层节点中心、采用伪逆法计算输出权值等参数,完成配色模型的建立。该配色模型可以快速完成柔印配色,并且具有较高的配色精度。  相似文献   

6.
提出了一种基于径向基函数神经网络的网络流量识别方法。根据实际网络中的流量数据,建立了一个基于RBF神经网络的流量识别模型。先介绍了RBF神经网络的结构设计及学习算法,针对RBF神经网络在隐节点过多的情况下算法过于复杂的缺点,采用了优化的算法计算隐含层节点。仿真实验证明,该模型具有较好的准确率、低复杂度、高识别效果和良好的自适应性。  相似文献   

7.
基于多物种进化遗传算法的神经网络结构学习方法   总被引:4,自引:1,他引:4  
针对神经网络结构设计的问题及一般结构学习方法的不足,提出了基于多物种进化遗传算法(SEGA),并以MLP为例给出了基于此算法的神经网络结构进化设计方法。该方法融合了遗传算法与神经网络的特点,具有模型搜索空间广泛、算法适应性强的特点。仿真结果表明该方法是有效的。  相似文献   

8.
针对隐马尔科夫模型(HMM)在跨站脚本检测中对初始先验假设估计不准确和以极大似然准则规定的HMM参数分类能力差的缺陷,提出了一种基于MLP-HMM的跨站脚本检测模型。首先,使用自然语言处理(NLP)方法解决数据高维复杂性问题。然后,通过多层感知机(MLP)神经网络学习对整个模型进行权值微调得到初始观察矩阵。最后,将该观察矩阵代入HMM中,增强HMM参数构建能力和分类能力。结果表明,结合MLP的HMM相比于原始HMM以及传统算法在跨站脚本检测上检测率有显著提高,并缩短了检测时间。  相似文献   

9.
针对传统行为选择机制(ASM)不能很好地做出控制决策的问题,提出一种基于多层感知(MLP)前馈神经网络的ASM,并将其应用到移动机器人目标跟踪中。首先,根据具体应用场景预定义多个机器人行为。然后,根据机器人配备的图像和红外传感器获得的目标位置和障碍物信息,通过MLP神经网络从预定义行为中选择出所需执行的行为。另外,为了构造最优的MLP模型,采用一种简化粒子群算法(SPSO)来优化网络权值参数。机器人目标跟踪仿真的结果表明,提出的ASM能够准确选择出合适的行为,实现了控制机器人跟踪目标移动且能够避开各种障碍物。  相似文献   

10.
针对欠驱动船舶在稳定航速条件下轨迹跟踪问题,提出了一种基于自适应神经网络与反步法相结合的控制算法.该算法将实际的欠驱动船舶视为模型完全未知的非线性系统,利用神经网络的函数逼近特性实现控制器中非线性部分的在线估计,采用同时调整输入层-隐层、隐层-输出层间的权值阵的方法进行神经网络权值调整.通过选取积分型Lyapunov函数证明了闭环系统的稳定性.仿真实验表明该控制策略具有良好的跟踪特性,可以实现对期望航迹的精确跟踪.  相似文献   

11.
在机器视觉领域,颜色恒常性是实现计算机视觉颜色校正和保持机器对颜色识别稳定性的重要因素.该模型通过心理物理实验获得由人眼感知得到的颜色恒常感知数据,将其放入神经网络中进行样本训练,并用遗传算法优化BP神经网络的连接权值和阈值.将所建立颜色恒常感知计算模型应用到图像颜色校正,通过主观和客观两个方面对校正结果进行对比评价,结果表示所建立的颜色恒常感知计算模型计算精度和效率高、复杂度低,比几种经典算法处理误差要小,针对图像的颜色再现有着更为符合人眼感知的特性.  相似文献   

12.
A hybrid linear/nonlinear training algorithm for feedforward neuralnetworks   总被引:1,自引:0,他引:1  
This paper presents a new hybrid optimization strategy for training feedforward neural networks. The algorithm combines gradient-based optimization of nonlinear weights with singular value decomposition (SVD) computation of linear weights in one integrated routine. It is described for the multilayer perceptron (MLP) and radial basis function (RBF) networks and then extended to the local model network (LMN), a new feedforward structure in which a global nonlinear model is constructed from a set of locally valid submodels. Simulation results are presented demonstrating the superiority of the new hybrid training scheme compared to second-order gradient methods. It is particularly effective for the LMN architecture where the linear to nonlinear parameter ratio is large.  相似文献   

13.
This paper presents a harmonic extraction algorithm using artificial neural networks for Dynamic Voltage Restorers (DVRs). The suggested algorithm employs a feed forward Multi Layer Perceptron (MLP) Neural Network with error back propagation learning to effectively track and extract the 3rd and 5th voltage harmonics. For this purpose, two different MLP neural network structures are constructed and their performances compared. The effects of hidden layer, supervisors and learning rate are also presented. The proposed MLP Neural Network algorithm is trained and tested in MATLAB program environment. The results show that MLP neural network enable to extract each harmonic effectively.  相似文献   

14.
In this work we present a constructive algorithm capable of producing arbitrarily connected feedforward neural network architectures for classification problems. Architecture and synaptic weights of the neural network should be defined by the learning procedure. The main purpose is to obtain a parsimonious neural network, in the form of a hybrid and dedicate linear/nonlinear classification model, which can guide to high levels of performance in terms of generalization. Though not being a global optimization algorithm, nor a population-based metaheuristics, the constructive approach has mechanisms to avoid premature convergence, by mixing growing and pruning processes, and also by implementing a relaxation strategy for the learning error. The synaptic weights of the neural networks produced by the constructive mechanism are adjusted by a quasi-Newton method, and the decision to grow or prune the current network is based on a mutual information criterion. A set of benchmark experiments, including artificial and real datasets, indicates that the new proposal presents a favorable performance when compared with alternative approaches in the literature, such as traditional MLP, mixture of heterogeneous experts, cascade correlation networks and an evolutionary programming system, in terms of both classification accuracy and parsimony of the obtained classifier.  相似文献   

15.
This paper introduces a methodology for neural network global optimization. The aim is the simultaneous optimization of multilayer perceptron (MLP) network weights and architectures, in order to generate topologies with few connections and high classification performance for any data sets. The approach combines the advantages of simulated annealing, tabu search and the backpropagation training algorithm in order to generate an automatic process for producing networks with high classification performance and low complexity. Experimental results obtained with four classification problems and one prediction problem has shown to be better than those obtained by the most commonly used optimization techniques  相似文献   

16.
P.A.  C.  M.  J.C.   《Neurocomputing》2009,72(13-15):2731
This paper proposes a hybrid neural network model using a possible combination of different transfer projection functions (sigmoidal unit, SU, product unit, PU) and kernel functions (radial basis function, RBF) in the hidden layer of a feed-forward neural network. An evolutionary algorithm is adapted to this model and applied for learning the architecture, weights and node typology. Three different combined basis function models are proposed with all the different pairs that can be obtained with SU, PU and RBF nodes: product–sigmoidal unit (PSU) neural networks, product–radial basis function (PRBF) neural networks, and sigmoidal–radial basis function (SRBF) neural networks; and these are compared to the corresponding pure models: product unit neural network (PUNN), multilayer perceptron (MLP) and the RBF neural network. The proposals are tested using ten benchmark classification problems from well known machine learning problems. Combined functions using projection and kernel functions are found to be better than pure basis functions for the task of classification in several datasets.  相似文献   

17.
Ever growing Internet causes the availability of information. However, it also provides a suitable space for malicious activities, so security is crucial in this virtual environment. The network intrusion detection system (NIDS) is a popular tool to counter attacks against computer networks. This valuable tool can be realized using machine learning methods and intrusion datasets. Traditional datasets are usually packet-based in which all network packets are analyzed for intrusion detection in a time-consuming process. On the other hand, the recent spread of 1–10-Gbps-technologies have clearly pointed out that scalability is a growing problem. In this way, flow-based solutions can help to solve the problem by reduction of data and processing time, opening the way to high-speed detection on large infrastructures. Besides, NIDS should be capable of detecting new malicious activities. Artificial neural network-based NIDSs can detect unseen attacks, so a multi-layer perceptron (MLP) neural classifier is used in this study to distinguish benign and malicious traffic in a flow-based NIDS. In this way, a modified gravitational search algorithm (MGSA), as a modern heuristic technique, is employed to optimize the interconnection weights of the neural anomaly detector. The proposed scheme is trained using an enhanced version of the first labeled flow-based dataset for intrusion detection introduced in 2009. In addition, the particle swarm optimization (PSO) algorithm and traditional error back-propagation (EBP) algorithm are employed to train MLP, so performance comparison becomes possible. The experimental results based on the actual network data show that the MGSA-optimized neural anomaly detector is effective for monitoring abnormal traffic flows in the gigabytes traffic environment, and the accuracy is about 97.8 %.  相似文献   

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