基于多层前馈神经网络的案例推理系统

采用基于该神经网络技术的案例推理系统,使用交叉覆盖算法,可兰亨登地缩减案例的检索时间、减少案例适应性修改、提高推磊效率。实验表明该系统易于设计构建,极大地提升了CBR在实际中的应用能力。     

前馈多层神经网络的一种高效加速算法

前馈多层神经网络是应用最广泛的一种人工神经网络,在各门学科领域中都具有很重要的实用价值,其学习能力和容错能力对不确定性模式识别问题的求解具有独到之处。前馈多层神经网络所使用的BP算法虽然简单且易于实现,但收敛速度缓慢。因此基于收敛速度及存储空间的考虑,文中着重探讨了一种较实用的BP网络优化算法－向量序列的ε－加速算法,并对相关的收敛性和稳定性作了理论上的分析和研究。实验结果表明这种方法有很好的效果。     

基于多层前馈神经网络的航天器在线故障检测系统设计

航天器在故障定位过程中易受原始电源信号的干扰,导致识别效果较差,为了解决该问题,提出了基于多层前馈神经网络的航天器在线故障检测系统设计。根据航天器在线故障检测原理及物联网技术设计系统总体架构,并分别对硬件部分及软件部分进行设计。硬件部分结合工业标准?PC组件,设计PXI机箱结构,完成对PXI测量模块的控制,利用MXI-4接口工具实现远程遥控,解决干扰信号对系统定位识别干扰。设计FPGA的EP3C10芯片外围结构,确定电路板主、子适配器管脚连接方式,利用2个高速?AD转换器差分采样,通过?FIFO存储采样结果。通过电子负载板继电器控制模块,控制信号阻断性能。构建基于多层前馈神经网络识别模型,依据确定性逻辑推理规则得出识别门限值,依据阈值设定具体识别流程,判断则判定参数有故障,完成系统设计。实验结果表明,该系统信号阻断效果优异,在距离为2和6 m时达到最大信号幅值0.9,故障模式的检测结果与理想结果一致,能够为航天器稳定运行提供设备支持。     

多层前馈神经网络改进算法及其应用

从前馈神经网络原理分析出发,提出一种速率适应因子方法用于对多层前馈神经网络中BP算法的改进,并将改进的算法用于XOR问题的学习及多重XOR分类器问题的学习。仿真结果表明,改进后BP的算法可显著加速网络的学习速度,并且学习过程具有良好的收敛性及较强的鲁棒性。     

模糊隶属度融合多层前馈神经网络的CBIR方法

针对大多数现有基于内容的图像检索方法的性能很大程度上依赖分类器的问题,提出了一种基于模糊隶属度融合神经网络的CBIR方法;首先,利用离散小波变换进行特征提取;然后,使用神经网络计算查询图像的类标签和模糊类隶属度;最后,利用简单与加权距离度量的组合在完整搜索空间中进行检索;在3个纹理类数目、方向和复杂度都不同的数据库上进行实验验证了所提方法的有效性,实验结果表明,相比其他几种较新的纹理图像检索方法,所提方法取得了更好的检索性能。     

基于二元蚁群算法的多层前馈神经网络

提出了一种基于二元蚁群算法的多层前馈神经网络,同时为了避免二元蚁群算法陷入局部最优引入了拥挤交通组织策略。将二元蚁群算法和神经网络混合,可兼有神经网络广泛映射能力和二元蚁群算法快速全局收敛能力,通过在函数逼近实验表明取得了较好的结果。     

常见遗传多层前馈神经网络实数编码的不合理性分析和改进*

对遗传多层前馈神经网络常见的实数编码中不适合于优化权值大小、不利于交叉算子发挥作用等问题。进行了理论分析,提出了“最小模式”等概念,并据此对编码方式做了改进,通过一个实例的仿真结果表明改进后的编码方式具有较好的寻优效果。     

基于跨越连接的多层前馈神经网络结构分析

任何连接方式的神经网络总可以归结为跨越连接网络。在传统多层前馈神经网络算法的基础上,提出了完全全连接神经网络的概念,给出了基于跨越连接的多层前馈神经网络算法。通过分析多层前馈神经网络的误差函数,从理论上证明了：相对于无跨越连接网络,基于跨越连接的多层前馈神经网络能以更加简洁的结构逼近理想状态。最后,用一个隐层神经元解决了XOR问题。     

基于多层前馈神经网络的分组密码设计

基于多层前馈神经网络的特性和分组密码的设计原则,构造了一种分组密码的数学模型,并用一个两层前馈网络具体实现了该分组密码体制.通过仿真,说明了该分组密码体制是可行的;通过对其安全性进行分析并与DES相比较,说明该分组密码体制具有较高的安全性,具有很好的混乱特征和扩散特征,并易于实现.     

多层神经网络BP算法的初步研究

目前,在数十种神经网络模型中以BP算法作为学习方式的多层神经网络是使用得最为广泛的一种。该网络是由Rumechere和Mccelland领导的研究小组在1985年实现的,已有效地解决了XOR、T-C匹配等感知器所不能解决的问题。现已广泛应用于语音识别、模式分类、过程监控等领域。尽管多层神经网络的BP算法较有效,但由于它用于高     

基于本体的案例推理模型研究*

提出了基于本体的案例检索及相似性评估方法和基于本体的案例适配模型,使得CBR(case-based reasoning)系统的开发可在语义层次上进行相似性评估和案例适配,这样得到的结果更能反映用户的真实需求;并且CBR所需要的领域知识可从本体中获取,大大降低了传统CBR系统中知识获取的瓶颈。最后在此基础上,提出了基于本体的CBR系统模型框架,从软件复用的角度提高了CBR系统的开发效率。     

基于实例推理的企业动态联盟伙伴选择与优化模型

将基于案例的推理方法运用于动态联盟伙伴企业选择与优化系统中,建立了伙伴企业选择系统的模型。具体讨论了方案库和评价结果库的建立,提出了基于灰色关联理论和模糊集理论相结合的相似度计算方法,从而可以准确地检索到相近案例,提高了伙伴企业选择的效率和准确性。     

用综合法优化前向神经网络结构

在神经网络研究中,如何确定神经网的结构是一个重要的研究方向.提出了一种通用的确定前向神经网络结构的自适应方法,即先用动态增长法快速训练网络拓扑结构及权值至满足给定的误差为止,然后用遗传算法(GA)对训练好的网络剪枝.实验表明,算法具有较好的通用性和可扩展性,收敛速度较快,对进一步的数据挖掘具有重要的意义.     

利用人工鱼群算法优化前向神经网络

人工鱼群算法(AFSA)是一种最新提出的新型的寻优策略，文中尝试将人工鱼群算法用于三层前向神经网络的训练过程，建立了相应的优化模型，进行了实际的编程计算，并与加动量项的BP算法、演化算法以及模拟退火算法进行比较，结果表明AFSA具有鲁棒性强，全局收敛性好，以及对初值的不敏感性等特点。     

A case-based reasoning approach for building a decision model

A methodology based on case-based reasoning is proposed to build a topological-level influence diagram. It is then applied to a project proposal review process. The formulation of decision problems requires much time and effort, and the resulting model, such as an influence diagram, is applicable only to one specific problem. However, some prior knowledge from the experience in modeling influence diagrams can be utilized to resolve other similar decision problems. The basic idea of case-based reasoning is that humans reuse the problem-solving experience to solve new problems.
In this paper, we suggest case-based decision class analysis (CB-DCA), a methodology based on case-based reasoning, to build an influence diagram. CB-DCA is composed of a case retrieval procedure and an adaptation procedure. Two measures are suggested for the retrieval procedure, one a fitting ratio and the other a garbage ratio. The adaptation procedure is based on decision-analytic knowledge and decision participants' domain-specific knowledge. Our proposed methodology has been applied to an environmental review process in which decision-makers need decision models to decide whether a project proposal is accepted or not. Experimental results show that our methodology for decision class analysis provides decision-makers with robust knowledge-based support.     

基于免疫遗传算法的多层前向神经网络设计

利用一种基于免疫功能的遗传算法,设计多层前向神经网络,用于实现多层前向神经网络结构的确定和权值空间的搜索。仿真实验结果显示该算法具有比遗传算法和动量BP算法更好的全局收敛性和快速学习网络权值的能力。     

Principal component case-based reasoning ensemble for business failure prediction

Case-based reasoning (CBR) has several advantages for business failure prediction (BFP), including ease of understanding, explanation, and implementation and the ability to make suggestions on how to avoid failure. We constructed a new ensemble method of CBR that we termed principal component CBR ensemble (PC-CBR-E): it, was intended to improve the predictive ability of CBR in BFP by integrating the feature selection methods in the representation level, a hybrid of principal component analysis with its two classical CBR algorithms at the modeling level and weighted majority voting at the ensemble level. We statistically validated our method by comparing it with other methods, including the best base model, multivariate discriminant analysis, logistic regression, and the two classical CBR algorithms. The results from a one-tailed significance test indicated that PC-CBR-E produced superior predictive performance in Chinese short-term and medium-term BFP.     

一种基于代价敏感学习的范例推理方法及其应用研究

提出一种基于代价敏感学习的范例推理方法，可以对大规模、高维数据进行分类和预测。该算法在分类的同时，不断调整数据属性项权重，以减少由分类引起的误分代价。在某入侵检测数据分析中取得了较好的结果。     

The clustering-based case-based reasoning for imbalanced business failure prediction: a hybrid approach through integrating unsupervised process with supervised process

Case-based reasoning (CBR) is one of the main forecasting methods in business forecasting, which performs well in prediction and holds the ability of giving explanations for the results. In business failure prediction (BFP), the number of failed enterprises is relatively small, compared with the number of non-failed ones. However, the loss is huge when an enterprise fails. Therefore, it is necessary to develop methods (trained on imbalanced samples) which forecast well for this small proportion of failed enterprises and performs accurately on total accuracy meanwhile. Commonly used methods constructed on the assumption of balanced samples do not perform well in predicting minority samples on imbalanced samples consisting of the minority/failed enterprises and the majority/non-failed ones. This article develops a new method called clustering-based CBR (CBCBR), which integrates clustering analysis, an unsupervised process, with CBR, a supervised process, to enhance the efficiency of retrieving information from both minority and majority in CBR. In CBCBR, various case classes are firstly generated through hierarchical clustering inside stored experienced cases, and class centres are calculated out by integrating cases information in the same clustered class. When predicting the label of a target case, its nearest clustered case class is firstly retrieved by ranking similarities between the target case and each clustered case class centre. Then, nearest neighbours of the target case in the determined clustered case class are retrieved. Finally, labels of the nearest experienced cases are used in prediction. In the empirical experiment with two imbalanced samples from China, the performance of CBCBR was compared with the classical CBR, a support vector machine, a logistic regression and a multi-variant discriminate analysis. The results show that compared with the other four methods, CBCBR performed significantly better in terms of sensitivity for identifying the minority samples and generated high total accuracy meanwhile. The proposed approach makes CBR useful in imbalanced forecasting.     

基于前向神经网络的呈香物质识别方法研究

介绍了所研制的一个人工嗅觉装置,详细叙述该装置对呈香物质的识别过程。实验结果表明,采用SuperSAB算法可以显著地提高人工嗅觉装置对香气物质的分析识别速度,为在线检测提供了条件,同时实验结果的准确性也较满意。