基于统计分析的分阶段进化神经网络方法

基于统计分析和分阶段进化，提出一种新的进化神经网络设计方法．本文方法 的进化过程分三个阶段：第一阶段，首先按训练样本统计特性设计较小规模的神经网络；第 二阶段，引入所有训练样本，在第一阶段的基础上，逐步扩展网络结构，新添加的神经元总 是单独训练并以抵消原网络的输出误差为其训练目标，直至训练网络达到误差要求．第三阶 段，利用统计方法，将网络中非线性变换作用相似的神经元合并，简化网络结构．本文方法 一方面减轻了进化算法的压力,另一方面指出了网络进化的方向使得进化网络的学习过程不 再是黑箱问题．计算机仿真实验表明，该方法是有效的．     

CC4神经网络的分类性能理论分析

本文在提出规范、规范满等概念的基础上,对CC4神经网络分类计算的倾向性进行了理论分析.并针对文本分类,提出了基于神经网络的增量式索引建立方法,将以词频为基础表示的高维文本信息映射到低维数据空间.为了使CC4神经网络应用到基于文本信息空间索引的分类技术中,将空间索引变换为CC4神经网络可以接受的二值向量,使得CC4神经网络以空间索引为基础,进行文档分类.最后给出了相应的实验结果.     

ENSEMBLE ARTIFICIAL NEURAL NETWORKS FOR PREDICTION OF DEW POINT TEMPERATURE

Dew point temperature is needed as an input to calculate various meteorological variables. In general, it contributes to human and animal comfort levels. The goal of this study was to develop artificial neural network (ANN) models for dew point temperature prediction to improve upon previous research. These improvements included optimizing the stopping criteria, comparing seasonal models to year-round models, and developing ensemble ANNs to blend the output of seasonal models. For an ANN trained with 100,000 patterns per epoch, the error was reduced using a 2000-pattern stopping dataset at an interval of 20 learning events to decide when to stop training. Seasonal ANN models were blended in an ensemble ANN with the weight of the member networks determined using a fuzzy membership-type function based on the day of year. These ensemble models were shown to produce lower errors than year-round, nonensemble models. The mean absolute errors (MAEs) of the final models evaluated with an independent evaluation dataset included 0.795°C for a 2-hour prediction, 1.485°C for a 6-hour prediction, and 2.146°C for a 12-hour prediction. The final model MAEs, when compared to the previous research, were reduced by 0.008°C, 0.081°C, and 0.135°C, respectively. It can be concluded that the methods used in this research were effective in more accurately predicting year-round dew point temperature. The ANN models for different prediction periods were sequenced to provide a 12-hour dew point temperature prediction system for implementation on the Georgia Automated Environmental Monitoring Network website (www.georgiaweather.net).     

神经网络BP学习算法动力学分析

研究神经网络BP学习算法与微分动力系统的关系.指出BP学习算法的迭代式与相应的微分动力系统数值解Euler方法在一定条件下等价,且二者在解的渐近性方面是一致的.给出了神经网络BP学习算法与相应的微分动力系统解的存在性、唯一性定理和微分动力系统的零解稳定性定理.从理论上证明了神经网络的学习在一定条件下与微分动力系统的数值方法所得的数值解在渐近意义下是等价的,从而借助于微分动力系统的数值方法可以解决神经网络的学习问题.最后给出了用改进Euler方法训练BP网的例子.     

典型人工神经网络的结构、功能及其在智能系统中的应用

人工神经网络已在各个领域得到广泛的应用, 尤其是在智能系统中的非线性建模及其控制器的设计、模式分类与模式识别、联想记忆和优 化计算等方面更是得到人们的极大关注．本文从网络在智能系统中建模及控制器设计的具体 训练结构入手,详细介绍了BP网络在系统控制中的典型应用方式,并根据不同网络所具有的 功能,从性能对比的角度对人工神经网络在上述各方面的应用给予综述．     

APPLICATION OF ARTIFICIAL NEURAL NETWORKS FOR PREDICTING pH IN SEAWATER ALONG GAZA BEACH

Coastal water issues are gaining worldwide attention because of their impact on health and other environmental problems. This article is concerned with the comparison between artificial neural networks and statistical methods to predict the degree of acidity (pH) in the coastal waters along the Gaza beach. Multilayer perceptron (MLP) and radial basis function (RBF) neural networks are trained and developed with reference to three parameters (water temperature, wind velocity, and turbidity) to predict the level of pH in the seawater. Both networks were developed using the combination of the data collected from nine sites over a period of 4 years, including 294 samples for training and 90 samples for testing the performance of models. The results show that the MLP and RBF models have good ability to predict the pH level. Each network's performance was tested with different sets of data, and the results show satisfactory performance. Results of the developed networks were compared with the statistical regression method and found that the predictions of neural networks are better than the conventional methods. Predictions result show that artificial neural networks approach have good ability for the modeling of pH level in the coastal waters along Gaza beach. It is hoped that neural networks will prove to be a promising alternative to traditional methods used and can contribute in the improvement of the quality of seawater.     

APPLICATION OF ARTIFICIAL NEURAL NETWORKS IN CONTROLLED DRUG DELIVERY SYSTEMS

Estimation of release profiles of drugs normally requires time-consuming trial-and-error experiments. Feed-forward neural networks including multilayer perceptron (MLP), radial basis function network (RBFN), and generalized regression neural network (GRNN) are used to predict the release profile of betamethasone (BTM) and betamethasone acetate (BTMA) where in situ forming systems consist of poly (lactide-co-glycolide), N-methyl-1-2-pyrolidon, and ethyl heptanoat as a polymer, solvent, and additive, respectively. The input vectors of the artificial neural networks (ANNs) include drug concentration, gamma irradiation, additive substance, and type of drug. As the outputs of the ANNs, three features are extracted using the nonlinear principal component analysis technique. Leave-one-out cross-validation approach is used to train each ANN. We show that for estimation of BTM and BTMA release profiles, MLP outperforms GRNN and RBF networks in terms of reliability and efficiency.     

基于神经网络的现代谱分析以及用于电动机的诊断

介绍了现代谱的计算,分析了采用线性规划神经网络计算现代谱AR系数的方法、步骤和产生的最小误差,实现了用基于神经网络的现代谱计算完成电动机的诊断过程.从分析可以看出,基于神经网络的现代谱分析能很好完成电动机的诊断工作,其突出优点是能在极短的时间内完成计算.     

离散Hopfield双向联想记忆神经网络的稳定性分析

首先将离散Hopfield双向联想记忆神经网络转化成一个特殊的离散Hopfield网络模型.在此基础上,对离散Hopfield双向联想记忆神经网络的全局渐近稳定性和全局指数稳定性进行了新的分析.证明了神经网络连接权矩阵在给定的约束条件下有唯一的而且是渐近稳定的平衡点.利用Lyapunov方程正对角解的存在性得到了几个判定平衡点为全局渐近稳定和全局指数稳定的充分条件.这些条件可以用于设计全局渐近稳定和全局指数稳定的神经网络.所做的分析扩展了以前的稳定性结果.     

基于人工神经网络的“零数字”音频水印算法

提出了一种基于人工神经网络的数字音频水印算法.利用人工神经网络学习和自适应的特征,将音频信号的重要特征作为人工神经网络的输入,通过人工神经网络的学习,建立音频信号与水印信息的对应关系,达到在不修改音频信号情况下把水印"嵌入"到原始音频信号中.实验结果表明该算法具有很强的鲁棒性和抵抗常用信号处理方法处理的能力,并且在提取水印时不需要原始音频信号.     

人工神经网络用于蒸汽动力系统的故障诊断

文中对神经网络用于蒸汽动力系统的故障诊断进行了研究，提出了神经网络适宜的拓扑结构，并讨论了神经网络对高斯噪声的过滤作用。     

人工神经网络预报金属基复合材料焊接接头性能

以金属基复合材料扩散焊接为实施对象 ,采用人工神经网络的方法建立扩散焊接过程的静态模型 ,表征了扩散焊接接头质量与工艺参数之间的关系 ,验证了该模型的适用性 .在此基础上对上述焊接过程进行仿真 ,分析了金属基复合材料接头强度随焊接工艺参数的变化规律 ,从而探索出最佳焊接工艺规范 .所建立的静态模型与实际焊接过程良好吻合 ,为新材料焊接性的研究提供一条新途径     

基于人工神经元网络的控制系统模型简化的专家系统

本文研究并实现了一个基于人工神经元网络的控制系统模型简化的专家系统(简称为ESOMRT)。该系统适用于专家和非专家用户,能够针对更体的连续和离散时间的高阶控制系统模型和简化要求选择合适的简化方法,并可对简化质量从时域和频域方面进行评估。在构造这个系统的过程中,作者提出了智能数据库的概念,使用了过程型和人工神经元网络方法相结合的知识表达方式,并利用神经元网络的再学习机制实现了斗自动知识获取,该系统具有三种工作模式和友好的人机界面,使系统的智能水平比较高并有实用价值,现已在IBM-PC/XT和386机上运行。     

一种基于人工神经网络的快速超分辨率方法

图像的超分辨率是指利用一幅或者多幅的低分辨率图像,通过相应的算法来获得一幅对应的清晰的高分辨率图像.针对现有的基于学习的超分辨率方法低效率的问题,提出一种基于人工神经网络的快速超分辨率方法,该方法试图利用人工神经网络学习到高分辨率图像和低分辨率图像之间的函数关系,其理论基础来自于人工神经网络能够很好地求解流形学习中高维流形和低维流形之间的映射关系.     

具有任意结构换热网络的灵敏度分析

本文提出了一个计算任意结构换热网络灵敏度系数及灵敏度的通用数学模型，并给出了求解数学模型的方法。     

二阶神经网络的全局指数稳定性分析

当神经网络应用于最优化计算时,理想的情形是只有一个全局渐近稳定的平衡点,并且以指数速度趋近于平衡点,从而减少神经网络所需计算时间,二阶神经网络较一般神经网络具有更快的收敛速度,对于二阶连续型Hopfield神经网络,用Lyapunov方法讨论平衡点的全局指数稳定性,给出了平衡点全局指数稳定的几个判别准则,作为特例,获得了连续型Hopfield神经网络全局指数稳定的新判据。     

基于自组织竞争人工神经网络的抽油系统故障诊断

抽油系统的故障诊断技术一直是采油工程的一个重要研究课题。本文将自组织竞争神经网络应用于抽油系统的故障诊断中来实现示功图的自动聚类。自组织竞争神经网络具有良好的可训练性和分类能力,理想的泛化性能,是一种快速有效的分类方法,可用于抽油系统故障的实时诊断。     

AN ANALYSIS OF NEURAL NETWORKS AS SIMULATORS AND EMULATORS

Recent advances in artificial neural networks (ANNs) have led to the design and construction of neuroarchitectures as simulator and emulators of a variety of problems in science and engineering. Such problems include pattern recognition, prediction, optimization, associative memory, and control of dynamic systems. This paper offers an analytical overview of the most successful design, implementation, and application of neuroarchitectures as neurosimulators and neuroemulators. It also outlines historical notes on the formulation of basic biological neuron, artificial computational models, network architectures, and learning processes of the most common ANN; describes and analyzes neurosimulation on parallel architecture both in software and hardware (neurohardware); presents the simulation of ANNs on parallel architectures; gives a brief introduction of ANNs in vector microprocessor systems; and presents ANNs in terms of the "new technologies". Specifically, it discusses cellular computing, cellular neural networks (CNNs), a new proposition for unsupervised neural networks (UNNs), and pulse coupled neural networks (PCNNs).     

含噪声前馈神经网络误差函数的理论分析

误差函数的选择是前馈神经网络训练的关键问题。首先讨论了在输入输出样本均含噪声及只有输出样本含有噪声的情况下网络权向量W的极限性质，从而指出，在噪声存在的情况下，常用的最小方差型误差函数不是一个好的选择，所得结果为更深入的研究指出了方向。