基于遗传算法的Hopfield联想记忆吸引域的优化

由于一般离散Hopfield神经网络存在很多伪稳定点.使稳定点的吸引域变小.网络很难获得真正的最优解.因此,提出将遗传算法应用到Hopfield联想记忆神经网络中.利用遗传算法对复杂、多峰、非线性极不可微函数实现全局搜索性质.对Hopfield联想记忆吸引域进行优化,使待联想模式跳出伪模式的吸引域.使Hopfield网络在较高噪信比的情况下保持较高的联想成功率.仿真结果证明了该方法的有效性.     

基于小波变换Hopfield神经网络的手写体数字识别

手写数字识别是模式识别的一个分支,手写数字识别的方法很容易推广到其他一些相关问题,因此在模式识别领域中占有重要地位.虽然数字只有十种且笔划简单,但由于不同人书写习惯不同,上下文联系较小,要获得较高的识别率并不容易.本文提出了一种基于小波和Hopfield神经网络的手写体数字识别方法.该方法首先提取字符的小波特征,以它们作为神经网络的输入向量,然后用Hopfield网络进行识别.对字符样本的识别结果显示,此方法在识别错误率和识别效率等方面均有较好效果.     

基于离散Hopfield神经网络的数字识别实现

介绍了离散Hopfield神经网络的基本概念;以MATLAB为工具,根据Hopfield神经网络的相关知识,设计了一个具有联想记忆功能的离散型Hopfield神经网络,并给出了设计思路、设计步骤和测试结果。实验结果表明,通过联想记忆,对于带有一定噪声的数字点阵,Hopfield网络可以正确地进行识别,且当噪声强度为0．1时的识别效果较好。     

一种基于免疫和Hopfield神经网络的多峰值优化算法

分析了免疫算法和Hopfield神经网络的优缺点，提出了一种解决多峰值函数优化问题的混合算法。Hopfield神经网络易于硬件实现，具有简单、快速的优点，但是对初始值具有依赖性以及容易陷入局部极值。免疫算法具有识别多样性的特点，但搜索效率和精度不高。将两算法结合起来，优势互补。首先用免疫算法寻优，然后对所得具有全局多样性的解进行聚类分析，所得聚类中心作为Hopfield神经网络的初始搜索点，最后利用Hopfield神经网络逐个寻优。实验表明，该算法是一种有效的求解多峰函数优化问题的方法，与免疫算法相比，搜索效率和精度都较高。     

一种混沌Hopfiele网络及其在优化计算中的应用

文章讨论了神经网络算法在约束优化问题中的应用,提出了一种混沌神经网络模型。在Hopfield网络中引入混沌机制,首先在混沌动态下搜索,然后利用HNN梯度优化搜索。对非线性函数的优化问题仿真表明算法具有很强的克服陷入局部极小能力。     

一种混沌Hopfield网络及其在优化计算中的应用

文章讨论了神经网络算法在约束优化问题中的应用,提出了一种混沌神经网络模型。在Hopfield网络中引入混沌机制,首先在混沌动态下搜索,然后利用HNN梯度优化搜索。对非线性函数的优化问题仿真表明算法具有很强的克服陷入局部极小能力。     

混沌神经网络在求解优化问题中的应用

本文运用GCM混沌神经网络对Hopfield神经网络在求解优化方面的问题进行了改进。通过混沌遍历,可使Hopfield网络在整个相空间进行搜索,从而避免网络在运行过程中陷入局部极小值。通过对一个对弈的实例进行实验,结果显示Hopfield网络的寻优特性获得了较大改进。     

一种基于MATLAB的带噪声字符识别算法实现

MATLAB语言由于具有强大的矩阵运算能力而广泛的应用于各种控制领域。Hopfield神经网络是一种具有联想功能的反馈网络 ,它可以根据一定的规则计算出网络的权值 ,网络演变过程中不断更新各神经元的状态 ,问题之解便是网络演变到稳定时各神经元的状态。该文提出一种采用离散Hopfield神经网络识别带噪声的字符的方法 ,在MATLAB中用M语言进行编程、计算、仿真 ,从而验证这种方法的正确性。     

Hopfield神经网络在车牌照字符识别中的应用

介绍了Hopfield神经网络识别车牌照字符的方法,用Matlab完成了对车牌照数字识别的模拟,最后给出实验结果。     

Hopfield网络应用实例分析

分析离散型Hopfield神经网络在模式识别中应用以及连续型Hopfield网络在求解TSP问题中的应用，并给出仿真实例。总结了Hopfield网络在实际应用中的一般方法。     

小波Hopfield神经网络及其在优化中的应用

通过把Hopfield神经网络的sigmoid激励函数替换为Morlet小波函数,提出了一种新型的Hopfield神经网络——小波Hopfield神经网络(WHNN)。由于Morlet小波函数具有良好的局部逼近能力和较高的非线性度,因此WHNN在非线性函数寻优上表现出令人满意的较高精确度的效果。一个典型的函数优化例子表明小波Hopfield神经网络比Hopfield神经网络有较高的精确度。     

A Symmetric Probabilistic Encryption Scheme Based On CHNN Without Data Expansion

In 1999, Guo et al. proposed a new probabilistic symmetric probabilistic encryption scheme based on chaotic attractors of neural networks. The scheme is based on chaotic properties of the Overstoraged Hopfield Neural Network (OHNN). The approach bridges the relationship between neural network and cryptography. However, there are some problems in their scheme: (1) exhaustive search is needed to find all the attractors; (2) the data expansion in the paper is wrongly derived; (3) problem exists on creating the synaptic weight matrix. In this letter, we propose a symmetric probabilistic encryption scheme based on Clipped Hopfield Neural Network (CHNN), which solves the above mentioned problems. Furthermore, it keeps the length of the ciphertext equals to that of the plaintext.     

Multiuser Detection of Synchronous MC-CDMA in Multipath Fading Channels Using Hopfield Neural Networks

Sub-optimum multiuser reception using Hopfield Neural Network for synchronous Multicarrier Code-Division Multiple Access signals in a multipath fading channel is studied with respect to near-far ratio. We have shown that by the appropriate choice of Hopfield Neural Network parameters from the channel state information, the Hopfield network can collectively resolve the multipath fading effects and the multiple-access interference in the system. Moreover, the Hopfield Neural Network demonstrates multiple-access interference resilient performance regardless of the number of paths resolved at the receiver. We have also investigated the bit-error rate performance of the system with respect to channel estimation errors. Results show that performance of the proposed detection scheme is influenced by the correctness of the estimated channel state information.     

A novel hybrid-maximum neural network in stereo-matching process

In the present paper, the completely innovative architecture of artificial neural network based on Hopfield structure for solving a stereo-matching problem—hybrid neural network, consisting of the classical analog Hopfield neural network and the Maximum Neural Network—is described. The application of this kind of structure as a part of assistive device for visually impaired individuals is considered. The role of the analog Hopfield network is to find the attraction area of the global minimum, whereas Maximum Neural Network is finding accurate location of this minimum. The network presented here is characterized by an extremely high rate of work performance with the same accuracy as a classical Hopfield-like network, which makes it possible to use this kind of structure as a part of systems working in real time. The network considered here underwent experimental tests with the use of real stereo pictures as well as simulated stereo images. This enables error calculation and direct comparison with the classic analog Hopfield neural network as well as other networks proposed in the literature.     

用改进的竞争Hopfield神经网络求解多边形近似问题

多边形近似是提取曲线特征点和简化曲线描述的一种重要方法.提出一种改进的Hopfield神经网络多边形近似算法,该算法利用选择拐点策略减少了搜索空间,重新定义了神经网络的能量函数,使其更能反映优化目标;引?入合并拆分搜索策略,有效帮助神经网络脱离局部最小值.实验结果表明,提出的改进算法是有效的,比其它算法如关键点检测法、竞争Hopfield神经网络、混沌Hopfield神经网络、遗传算法等具有更优的性能.     

基于Gabor多通道滤波和Hopfield神经网络的纹理图象分割

文章针对纹理图象的特点,提出了一种基于Gabor多通道滤波和Hopfield神经网络的纹理图象的分割算法。首先构造一组Gabor滤波器（2－D）提取纹理图象多分辨率和多方向性的空域和频域特征。为了使纹理特征更加明显,在此基础上对滤波图象进行非线性变换,最后利用Hopfield神经网络通过松弛迭代算法实现纹理图象的快速分割,取得了良好的分割效果。     

Fuzzy Clustering Using A Compensated Fuzzy Hopfield Network

Hopfield neural networks are well known for cluster analysis with an unsupervised learning scheme. This class of networks is a set of heuristic procedures that suffers from several problems such as not guaranteed convergence and output depending on the sequence of input data. In this paper, a Compensated Fuzzy Hopfield Neural Network (CFHNN) is proposed which integrates a Compensated Fuzzy C-Means (CFCM) model into the learning scheme and updating strategies of the Hopfield neural network. The CFCM, modified from Penalized Fuzzy C-Means algorithm (PFCM), is embedded into a Hopfield net to avoid the NP-hard problem and to speed up the convergence rate for the clustering procedure. The proposed network also avoids determining values for the weighting factors in the energy function. In addition, its training scheme enables the network to learn more rapidly and more effectively than FCM and PFCM. In experimental results, the CFHNN method shows promising results in comparison with FCM and PFCM methods.     

基于Hopfield神经网络的WSN分布式拓扑

提出一种基于Hopfield神经网络模型的传感器网络的分布式广播算法。在已有网络拓扑的基础上对其数据获取方式进行改进。用优化的Hopfield神经网络模型在各簇中分别从广播源点开始遍历所有传感节点,并返回广播源点的最优链路。利用Hopfield神经网络收敛速率快、通信路径最优,且易于硬件电路实现的特点,形成了能量消耗较少、延时较小的WSN网络,它是一种能量高效的网络。     

Hysteretic HNN MAI-Cancellation for CDMA Signals in Multipath Fading Channels

Multiple-access interference cancellation using hysteretic Hopfield neural network receiver for direct sequence code-division multiple access (DS-CDMA) in multipath fading channels is investigated. It has been shown that by applying the phenomenon of “hysteresis” to the Hopfield neural network (HNN) detector, performance of this detector may be enhanced in all near-far situations for different number of multipath rays. Introducing the concept of Hysteresis into HNN has made this suboptimum CDMA detector even closer to the optimum multiuser CDMA detector. As shown by simulation results, the bit-error rate performance achieved by the Hysteretic Hopfield Neural Network detector outperforms the classical HNN detector with a good margin and is promising.     

A robust boundary-based object recognition in occlusion environment by hybrid Hopfield neural networks

This paper presents a new method of occluded object matching for machine vision applications. The current methods for occluded object matching lack robustness and require high computational effort. In this paper, a new Hybrid Hopfield Neural Network (HHN) algorithm, which combines the advantages of both a Continuous Hopfield Network (CHN) and a Discrete Hopfield Network (DHN), will be described and applied for partially occluded object recognition in a multi-context scenery. The HHN proposed as a new approach provides great fault tolerance and robustness and requires less computation time. Also, advantages of HHN such as reliability and speed will be discussed.