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1.
本文在分析判决反馈RBF网络信道均衡器(DFIBFNE)的结构特点基础上,定义一个布尔向量L作为网络的结构参数,与原来DFRBFNE的隐节点参数集一起构成了新的DFRBFNE隐节点参数集{c,d,L},并给出了一个新的DFRBFNE网络输入输出关系表达式;采用一种混合协同微粒群算法同时对DFRBFNE网络拓扑结构和隐层节点参数进行优化设计,并将输出线性参数集分离后采用最小二乘法进行优化设计,简化了优化空间,加速了算法的收敛速度。  相似文献   

2.
基于互信息的RBF神经网络结构优化设计   总被引:1,自引:1,他引:0  
郭伟 《计算机科学》2013,40(6):252-255
以设计最小RBF网络结构为着眼点,提出了一种基于互信息的RBF神经网络结构优化算法.该算法用k近邻统计法估计隐节点输出矩阵与输出节点输出矩阵之间的互信息,获得每个隐节点与输出节点之间的相关性度量,删除相关性最小的隐节点,进而达到优化网络结构的目的.该算法具有自恢复机制,在简化网络结构的同时能有效保证网络的信息处理能力.在人工数据集和真实基准数据集上的仿真实验验证了该算法的有效性与稳定性.  相似文献   

3.
基于RBF神经网络的非线性系统的预测   总被引:3,自引:2,他引:3  
对于非线性系统的预测辨识,提出用动态节点生成构造性RBF神经网络作为预测模型,且RBF神经网络的学习算法采用一种新的全监督式学习算法,即神经网络隐层引入新节点时,通过使新节点的输出尽可能逼近残差序列的方向来获取网络参数,从而减少学习误差,使网络输出能够较好的跟踪系统输出。仿真表明该学习算法的有效性。  相似文献   

4.
PSO聚类和梯度算法结合的RBF神经网络优化   总被引:1,自引:0,他引:1  
针对制约径向基函数RBF神经网络发展及其应用的瓶颈问题,提出一种基于粒子群优化算法PSO的改进K-means聚类思想,以确定其隐节点的数目.结合梯度算法,通过最小化目标函数调节隐节点的数据中心、宽度和输出权值,最终达到优化RBF神经网络的目的;同时,将优化后的网络应用于滚动轴承故障模式识别.试验结果表明,该方法能自适应地确定RBF神经网络隐节点的数目并调整其结构参数,使网络具有较快的收敛速度和较高的收敛精度,从而准确地识别滚动轴承的故障模式.  相似文献   

5.
梯度算法下RBF网的参数变化动态   总被引:2,自引:0,他引:2  
分析神经网络学习过程中各参数的变化动态,对理解网络的动力学行为,改进网络的结构和性能等具有积极意义.本文讨论了用梯度算法优化误差平方和损失函数时RBF网隐节点参数的变化动态,即算法收敛后各隐节点参数的可能取值.主要结论包括:如果算法收敛后损失函数不为零,则各隐节点将位于样本输入的加权聚类中心;如果损失函数为零,则网络中的冗余隐节点将出现萎缩、衰减、外移或重合现象.进一步的试验发现,对结构过大的RBF网,冗余隐节点的萎缩、外移、衰减和重合是频繁出现的现象.  相似文献   

6.
为了利用径向基函数(RBF)神经网络对混沌序列进行精确和快速的在线预测,提出一种在线构造变结构RBF神经网络的序贯学习算法。该算法建立实时更新的滑动数据窗口,通过学习窗口内的数据对隐节点进行增加和删除,动态确定RBF神经网络隐节点的数目及中心位置,并对隐层至输出层的连接权值进行在线调整。该算法具有调节参数少、学习速度快以及所得网络结构精简等特点。将该网络用于Mackey-Glass混沌时间序列的在线预测实验,结果验证该算法对该混沌序列具有良好的在线动态辨识和预测性能。  相似文献   

7.

针对RBF 神经网络的结构设计问题, 提出一种基于输出敏感度方差重要性的结构优化算法. 首先, 检验网络隐层节点的输出敏感度在样本集上的方差是否与零有显著差异, 以此作为依据增加或删除相应的隐层节点; 然后,对调整后的网络参数进行修正, 使网络具有更好的拟合精度和收敛性; 最后, 对所提出的优化算法进行仿真实验, 结果表明, 所提出的算法可根据研究对象自适应地调整RBF 的网络结构, 具有良好的逼近能力和泛化能力.

  相似文献   

8.
提出了一种新的结构自适应的径向基函数(RBF)神经网络模型。在该网络中,自组织映射(SOM)神经网络作为聚类网络,采用无监督学习算法对输入样本进行自组织分类,并将分类中心及其对应的权值向量传递给RBF神经网络,作为径向基函数的中心和相应的权值向量;RBF神经网络作为基础网络,采用高斯函数实现输入层到隐层的非线性映射,输出层则采用有监督学习算法训练网络的权值,从而实现输入层到输出层的非线性映射。通过对字母数据集进行仿真,表明该网络具有较好的性能。  相似文献   

9.
提出了一种新的结构自适应的径向基函数(RBF)神经网络模型。在该模型中,自组织映射(SOM)神经网络作为聚类网络,采用无监督学习算法对输入样本进行自组织分类,并将分类中心及其对应的权值向量传递给RBF神经网络,分别作为径向基函数的中心和相应的权值向量;RBF神经网络作为基础网络,采用高斯函数实现输入层到隐层的非线性映射,输出层则采用有监督学习算法训练网络的权值,从而实现输入层到输出层的非线性映射。通过对字母数据集进行仿真,表明该网络具有较好的性能。  相似文献   

10.
主要内容是建立一种基于RBF神经网络的语音识别系统,探讨RBF神经网络在语音识别中的应用.利用有序聚类算法对语音信号进行时间归整,构建一个RBF神经网络,采用自适应的方法确定网络隐节点的个数,用线性最小二乘法确定隐层到输出层的权值,用语音信号的LPCC参数的训练和识别.在Matlab中完成实验,语音信号的识别率达到85%,并且还有很大的提升空间.实验表明RBF神经网络在语音识别中有发展的前景.  相似文献   

11.
Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.  相似文献   

12.
European Community policy and the market   总被引:1,自引:0,他引:1  
Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.  相似文献   

13.
融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。  相似文献   

14.
为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.  相似文献   

15.
Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.  相似文献   

16.
This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.  相似文献   

17.
Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   

18.
Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.  相似文献   

19.
In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.  相似文献   

20.
《Information & Management》2016,53(6):787-802
Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.  相似文献   

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