基于Petri网的流程模型中最小变化域的分析方法

为了灵活适应市场业务需求变化,确定业务流程中的变化部分成为业务流程管理的核心问题.已有的研究都是建立在静态的分析基础上,通过给定的变化节点来搜索变化范围,具有一定的局限性.基于Petri网方法及行为轮廓思想对业务流程模型进行分析,从动态行为角度分别给出了寻找流程模型中的行为变化部分的方法,以及确定流程模型中最小变化域的分析方法.并给出一个具体的业务流程的实例,分析了该方法的有效性.     

基于概率和时间因素的Petri网业务流程一致性分析

业务流程一致性分析作为业务流程管理的重要内容之一,近年来一直是业务流程管理研究领域的热点。目前已有的方法主要从控制流和数据流两方面进行研究,在实际情况下,概率和时间因素会对业务流程产生较大的影响。因此,文中提出了一种基于概率和时间因素的Petri网业务流程一致性分析方法。首先,给出了基于概率因素的控制流Petri网和基于时间因素的数据流Petri网的定义;然后,将基于概率因素的控制流Petri网和基于时间因素的数据流Petri网中的所有变迁分别映射到原业务流程Petri网中,得到各自的行为映射表,并针对两种类型的Petri网提出相应的行为兼容度算法,依据行为兼容度的值来衡量业务流程的一致性程度;最后,进行实例分析,结果显示了该方法的有效性和优越性。     

区间速率连续Petri网模型行为分析研究

讨论了区间速率连续Petri网模型的行为分析问题．通过划分标识等价类提出了任意标识下区间速率连续Petri网各个迁移瞬时引发速率的求解方法，并在此基础上给出了区间速率连续Petri网的行为演变算法．同时给出了区间速率连续Petri网行为演变的混杂自动机模型构造方法．应用例子表明了所提出行为分析方法的有效性．     

基于三维行为关系图的模型一致性检测方法

在业务流程模型的相似性分析过程中,有时会出现环结构。已有的方法一般不考虑环结构,忽略了环结构对模型一致性分析的影响。以Petri网的多重变迁集为基础,提出一种新的一致性度测量方法。首先通过分析5种行为序列关系来刻画Petri网的变迁之间的相互关系,给出了三维行为关系图的概念;然后对Petri网的三维行为关系图间的关系进行研究,提出了基于Petri网的三维行为关系图的一致性检测方法。理论分析和实例测试均表明了该方法的有效性。     

基于Petri网的Web服务BPEL4WS建模与分析

描述了Web服务业务流程执行语言(BPEL4WS或BPEL)的Petri网建模方法，利用网结构描述基于Web服务业务流程的行为特性。在对BPEL4WS的结构性活动和故障补偿处理机制进行逐层分析的基础上，提出了一个利用Petri网的逐步求精技术对流程进行建模的算法。然后结合具体实例阐述了利用该算法建模的详细过程，并对所生成的Petri网模型进行了完整性（soundness)验证     

基于XAr/T-net的业务流程建模与分析

Petri网是对业务流程进行描述和分析的有效工具,但已有的基于Petri网的建模方法无法体现流程中关键业务数据的变化。Artifact作为业务流程中的数据实体,是具有嵌套结构的复杂数据对象。用一种图形化的XML模式定义语言描述Artifact的结构。将XML文档的操作与Petri网流程的定义相结合,对以Artifact为中心的业务流程建立一种可计算的XAr/T-net模型。在XAr/T-net模型的基础上,分析业务流程逻辑结构,并采用覆盖图分析Artifact的特性。     

基于Time Petri Nets的实时系统资源冲突检测

Time Petri Nets在实时系统的建模和性能分析中得到广泛应用,而冲突是Petri网及其扩展模型的重要行为,解决冲突是正确分析模型动态行为的关键.目前随机Petri网、混合Petri网和区间速率连续Petri网的冲突检测方法由于没有考虑到时间约束因此无法在TPN网中使用.时间约束的引入使得Time Petri Nets模型的使能和触发语义比Petri网模型的语义复杂,冲突检测变得更加困难.为了计算冲突发生的时间和概率,首先根据时间约束,给出了变迁持续使能时延迟区间的计算方法,并证明了该方法的合理性和完备性;然后在此基础上定义并证明了Time Petri Nets模型中不冲突的检测方法;并提出了Time Petri Nets模型的冲突检测方法,给出了冲突时间区间和变迁实施概率的计算方法;最后通过实例验证说明了该方法的正确性和有效性.     

组合Web服务事务的补偿语义研究

Web服务组合需要可靠的事务处理机制,而目前仅依赖传统的ACID机制进行组合事务处理无法满足需要。为此提出一种基于配对Petri网的结构化补偿方法,该方法基于配对Petri网描述基本聚合结构的Web服务组合及其补偿行为。借助配对Petri网的动态执行推演技术分析了聚合结构补偿的执行语义,分析表明该方法可用于可靠业务流程组合、聚合补偿和组合流程优化等方面。     

基于配置变迁的业务流程模型优化分析方法

为了灵活适应市场需求,业务流程模型的优化分析显得越来越重要。已有的方法大部分基于静态定位变化区域,进而对该区域进行优化,具有一定的局限性。基于Petri网的方法和行为轮廓的思想从行为角度来动态分析业务流程中的变化部分,利用日志与模型的匹配关系以及动态定位来确定模型中的变化域,考虑接口部分,利用适合度和行为适当性,通过配置变迁优化模型,然后利用行为轮廓一致性度判定最优模型,最后用实例验证该方法的可行性。     

基于Time Petri Net的实时系统冲撞检测与消解

time Petri net(TPN)在实时控制系统的建模中得到广泛应用,而冲撞是Petri网及其扩展模型的重要行为,解决冲撞是正确分析模型动态行为的关键.由于引入时间约束,使得TPN模型的使能和触发语义比Petri网模型的语义复杂,冲撞的检测及消解变得更加困难.首先根据时间约束,给出了变迁持续使能时延迟区间的计算方法,并证明了该方法的正确性;然后在此基础上定义并证明了TPN模型中冲撞的检测方法;给出了冲撞时间区间及修改时间约束的冲撞消解方法;最后通过实例验证说明了该方法的有效性和正确性.     

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.     

European Community policy and the market

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.     

一种自适应子融合集成多分类器方法

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。     

Avoiding semantic and temporal gaps in developing software intensive systems

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.     

Designing economic np control charts: A programmed simulation approach

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.     

The development of robot art

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     

Explanation and prediction: an architecture for default and abductive reasoning

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.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。