一种基于可信度的不确定性推理及其神经网络实现*

提出了基于可信度因子和可信度区间的不确定性推理模型,并用改进的BP神经网络实现其推理过程,最后利用MATLAB神经网络工具箱给出仿真示例。改进的BP神经网络在实现不确定性推理方面有效避免了沿用传统方法所带来的规则数激增及推理缓慢等缺陷,并提高了网络的泛化能力。仿真示例表明,它不仅可以自动学习和模拟专家的典型经验,而且还可以将专家的典型经验推广应用到一般情形。     

一种基于ANN的中医辨证不确定性推理模型研究

提出中医辨证中不确定性推理的基于可信度因子和可信度区间的模型,并用改进的BP神经网络实现其推理过程,最后利用MATLAB神经网络工具箱给出仿真示例。改进的BP神经网络在实现中医辨证不确定性推理方面有效地避免了沿用传统方法所带来的规则数激增及推理缓慢等缺陷,并提高了网络的泛化能力。仿真示例表明,它不仅可以自动学习和模拟专家的典型经验,而且可以将专家的典型经验推广应用到一般情形。     

中医舌诊系统中智能推理可信度的研究

中医舌诊是一个极其复杂的过程,是以舌症彩色图像的识别为主,并综合考虑脉象和其它临床数据的中医医疗诊断方法.可信度方法是人工智能领域的一种不确定推理方法,它通过量化不确定知识将不确定信息确定化,被广泛用于处理各种随机不确定信息.通过融合模糊逻辑推理、神经网络技术及可拓学方法,研究了一种基于竞争神经网络的中医舌诊智能推理模型,以VC 6.0和SQL Server2000为开发工具,实现了对中医专家诊断推理过程的模拟.并在推理过程中嵌入了可信度的评价体系,对输入模式信息和专家经验信息的关系引入了可信度度量,借鉴贝叶斯理论方法对神经网络的推理结果的可信度进行了研究,从而使诊断准确率大大提高,且系统使用简洁、方便.     

基于BP神经网络的水牛疾病诊断系统

针对传统专家系统获取知识困难自学习能力差和推理能力弱等缺点,设计并实现了基于BP神经网络的水牛疾病诊断专家系统.系统用专家以往诊断水牛疾病的病历来训练神经网络,并通过训练过的神经网络来实现疾病的诊断,然后针对诊断结果进行反向推理以确诊水牛疾病,结果表明,该系统很好地改进了传统专家系统存在的一些缺点.另外,该水牛疾病诊断系统的实现方法可推广应用到其它动物的疾病诊断系统中,为疾病诊断系统的开发提供了一条有效的新途径.     

基于犹豫模糊可信度的知识推理

针对不确定性推理中的可信度估值不精确的问题,将犹豫模糊集引入可信度不确定性推理中。提出犹豫模糊可信度的定义,并基于可信度的知识表示给出犹豫模糊可信度的知识表示方式。为解决专家在推理过程中出现的信息缺失问题,提出求解平均值的信息补全方法。构建犹豫模糊可信度的单条规则和多条规则并行关系的运算法则,并给出基于犹豫模糊可信度的知识表示与推理的具体步骤。最后,运用实例验证了所提算法的可行性及有效性。     

不确定性推理的实用性研究

Bayes 概率推理是不确定性推理方法之一,它在理论上虽然比较简单,但当证据之间不满足独立性假定时,推理过程中需要专家给出的先验概率个数将按几何级数增加,这严重影响了 Bayes 概率推理的实用性.本文提出的两种处理非独立性问题的概率推理方法,不仅可以大大减少专家的工作量,而且比较简单、直观,便于实际应用.     

基于最大熵NN的教学质量评价模型及仿真

教学质量评价是教学管理中的重要工作,其关键是建立影响教学质量的众多指标与评价结果间的复杂非线性关系模型.BP神经网络虽能建立相关模型,但却在建模过程中未考虑由专家经验知识所积累的各评价指标与评价结果的不确定性分布信息,导致模型预测的评价结果准确性差且模型泛化性能弱.为此,本文选用具备刻画不确定性分布信息功能的最大熵准则替换BP算法中的均方误差准则,从而获得教学质量的最大熵神经网络评价模型.数据仿真和重庆理工大学50名教师评价实例均显示,改进模型的预测评价结果相对误差均在6％内,且明显优于传统BP神经网络模型.表明了改进模型的评价结果具有很高的可信性和较强的泛化能力,从而为实现教学质量的准确评价提供了一个可行方法.     

基于知识的航电设备故障诊断专家系统

为了解决航电设备故障难以诊断的问题,设计一个基于知识的航电设备故障诊断专家系统。该系统中的知识表示形式及与之相配合的基于确定性理论模型的不确定性推理方法,以及基于示例的推理方法可以实现航电设备的故障推理和诊断,其规则的可信度可达到理想的程度。     

软件风险评估量化分析研究

为解决软件风险评估完全凭借专家经验产生的主观性和模糊性问题,提出了基于进化神经网络模型的软件风险定量评估方法.通过研究软件风险评估过程,提出了软件风险评估指标体系模型,同时运用模糊理论将风险因素量化以此作为进化神经网络的输入值.将改进的粒子群算法(PSO)、BP神经网络相结合,构建了基于改进BP神经网络的进化神经网络模型.对提出的模型和改进的算法进行模拟仿真实验,实验结果表明了该方法对软件风险评估量化分析的可行性.     

用于态势评估中因果推理的贝叶斯网络

1 引言贝叶斯网络是由R.Howard和J.Matheson于1981年提出来的,它主要用来表述不确定的专家知识。后来经过J.Pearl,D.Heckerman等人的研究,贝叶斯网络的理论及算法有了很大的发展。作为一种知识表示和进行概率推理的框架,贝叶斯网络在具有内在不确定性的推理和决策问题中已经得到了广泛的应用,例如概率专家系统、计算机视觉和数据挖掘等。     

煤矿井下安全监控分站的设计及其仿真实现

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.     

Call for Papers The 6^th International Conference on Grid and Cooperative Computing

Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.     

Only connect: teaching, technology and telesis

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.     

View-based model-driven architecture for enhancing maintainability of data access services

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.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

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.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate