ARTEMIS-ARC系统协同模型的自省式实现技术研究

基于运行时体系结构的协同模型能够为面向服务的协同应用系统的动态演化提供有效的支持。但是在实现层面上,如何使软件体系结构从抽象的规约转化为运行时实际的对象实体,并成为系统演化行为的直接载体,是一个较为困难的技术挑战。针对这个问题,本文提出一种基于计算自省的实现途径,主要包括基于面向对象程序设计语言构造的体系结构层面的元表示和元协议、基于体系结构上下文中对象引用重解释构建的因果互连机制,以及基于该因果互连机制的应用系统的动态重配置。以上实现方式在自行开发的服务协同系统ARTEMIS-ARC时得以实施。     

面向体系结构的可视化服务集成开发环境Artemis-VIDE

为支持直观易扩展的软件服务集成和所集成之应用系统的动态演化,本文提出了一个面向体系结构的可视化服务集成开发环境。该环境支持以图形化的方式定义系统的软件体系结构及相关协同逻辑,并据此生成内置于应用系统之中的运行时刻体系结构对象,作为应用系统运行和演化的基础。该环境还集成了服务搜索、基于图文法的体系结构检查等功能,为系统的开发、运行、监控和动态演化提供了一个一致、易用、可扩展的支撑平台。     

一种演化超图文法到状态转移系统的映射方法

运用模型检测技术验证动态演化的正确性,是近年来软件体系结构动态演化研究领域面临的一个挑战.然而,当前的方法很少考虑软件体系结构动态演化时的相关条件.针对该问题,提出用条件状态转移系统表示软件体系结构动态演化的状态模型,将软件体系结构超图映射为状态,演化规则运用映射为条件状态转移关系,给出软件体系结构动态演化的条件超图文法到条件状态转移系统的映射方法以及相应的实现算法,实现了软件体系结构动态演化的条件状态转移系统的构建,并证明了在该映射方法下,软件体系结构动态演化条件超图文法与条件状态转移系统的互模拟等价.最后通过案例分析,运用该方法以及模型检测技术,验证了软件体系结构动态演化的相关性质,从而验证了该方法的有效性.     

一种基于反射机制的OWL-S需求规约演化方法

软件系统面临用户需求、软件资源和系统上下文环境等方面变化的挑战,软件需求不可避免地要求持续的演化。反射目前被用于软件系统的运行时管理和动态演化等方面,但还没有用于软件需求规约的演化。提出了一种基于反射机制的OWL-S需求规约演化方法,通过描述支持OWL-S需求规约演化的元信息,并以合理的方式使用这些元信息,实现OWL-S需求规约的演化。利用这种方法,需求分析人员可以有效地管理需求变更,以一种可控、有序的方式完成需求规约的演化任务。     

一个面向服务的支持动态演化的软件模型

为了使面向服务的架构更适应动态演化的需求,提出了基于体系结构空间、支持动态演化的软件模型SASM．SASM是使用反射技术,通过具有因果相联的基层和元层来构造．基层由可运行的服务形成,元层是一个具备树形层次、层间存在求精关系的体系结构空间．该空间反映了需求的层次性,提供给用户不同抽象级别的视图和管理手段．通过对体系结构空间的观察,可获知系统的结构和行为信息．通过对体系结构空间的在线调整可实现对基层的修改进而实现系统的非预设动态演化,而空间中不同层次之间的求精关系保证了应用的完整性和演化的一致性．     

运行时软件体系结构的建模与维护

运行时体系结构是系统运行时刻的一个动态、结构化的抽象,描述系统当前的组成成分、各成分的状态和配置以及不同成分之间的关系.运行时体系结构与目标系统间具有动态的因果关联,即系统的变化及时体现在体系结构上,而对体系结构的修改及时影响当前系统.运行时体系结构允许开发者以读写体系结构的方式实现系统的监测和调整,是体系结构层次系统动态适应与在线演化的基础.构造运行时体系结构的关键是针对不同的目标系统和体系结构风格实现合适的基础设施,以维护二者之间的因果关联.由于目标系统和体系结构的多样性以及因果关联维护逻辑的复杂性,这一构造过程往往过于繁琐、易错、难以复用和维护.提出一种模型驱动的运行时体系结构构造方法.开发者只需针对目标系统、体系结构以及两者之间的关系分别进行建模,根据这些模型,支撑框架自动构造合法而高效的运行时体系结构基础设施.基于MOF 和QVT 标准建模语言定义了一组运行时体系结构建模语言,并基于通用的模型与系统间同步技术实现了相应的支撑框架.一系列实例研究表明,该方法具有广泛的适用性,并显著提高了运行时体系结构构造过程的效率与可复用性.     

基于关联矩阵的软件体系结构动态演化及其实现

针对当前软件体系结构动态演化方法很少考虑组成元素之间关联的问题, 从关联的角度考虑软件体系结构的组成, 用关联矩阵和关联基数矩阵描述软件体系结构及其动态演化的各项需求, 提出了一种基于关联矩阵的软件体系结构动态演化方法, 并设计相应的算法进行实现, 最后通过案例进行分析和实验, 验证了方法的有效性。本方法可有效地实现软件体系结构动态演化的可追踪性和可控性。     

并行自动测试系统软件体系结构建模

针对并行自动测试系统软件开发难度大的问题,对其软件体系结构进行研究,提出层次化风格的并行自动测试系统软件体系结构及五视图的软件体系结构描述模型,建立该软件体系结构的需求功能视图、框架视图、静态结构视图、动态过程视图和物理实现视图。该描述模型可以对并行自动测试系统的软件体系结构进行全面的分析,有利于指导系统的实际开发。     

一种面向对象替换的灵活在线演化框架

在面临动态、复杂多变的运行环境以及用户灵活多变的需求时,软件要能及时调整其结构和行为,以适应环境以及需求的变更,达到延长软件系统生命周期的目标,即具有在线演化的特性.在线演化是当前软件体系结构中研究的热点,本文在研究自适应演化的过程中,基于面向对象程序模型,利用动态对象替换的机制,提出一种灵活的在线演化框架.通过具体的实例验证,该机制简单灵活,适合软件的在线调整,满足软件运行时变更的需求.     

Bigraph理论在自适应软件体系结构上的应用

现有的软件体系结构形式化方法对体系结构的动态性、自适应性支持有限,并不能很好地验证系统演化过程中的一致性、完整性等动态特征.Bigraph理论融合了,π演算和移动Ambient演算的优势,重点强调计算的位置和连接两方面因素,具有较为完整、可扩展的理论框架.这使得Bigraph不仅在概念上能够满足现有自适应软件对结构和行为的需求,而且还提供了直观、普适的表达能力.文中简要介绍了Bigraph的基本概念和现状,利用Bigraph理论对自适应软件体系结构进行了形式化规约,分析和验证了系统动态演化的性质,并探讨了Bigraph理论在自适应软件体系结构形式化方面的优势和拓展方向.     

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。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.