基于XACML的Web服务访问控制研究

详细介绍了Web服务授权和访问控制机制中一个重要规范：可扩展访问控制标记语言（XACML）,给出了基于XACML的访问控制模型的执行流程,使用SUN公司提供的XACML工具包实现了一个具体应用。最后得出此模型更加灵活、安全的结论,特别适用于异构的Web服务环境,并对XACML的发展作了展望。     

基于SRP协议的Web服务移动agent访问控制研究*

针对Web服务安全问题中的访问控制,提出将移动agent引入Web服务的安全访问控制模型,基于SRP协议对Web服务附加了一个独立的访问控制代理层,实现了基于移动agent的Web服务访问控制模型,并对控制流程进行了描述。     

基于SRP协议的Web服务移动agent访问控制研究*

针对Web服务安全问题中的访问控制,提出将移动agent引入Web服务的安全访问控制模型,基于SRP协议对Web服务附加了一个独立的访问控制代理层,实现了基于移动agent的Web服务访问控制模型,并对控制流程进行了描述。     

基于SOAP消息处理链的Web服务访问控制模型

为了能更加安全有效地访问Web服务,设计一种基于SOAP消息处理链的Web服务访问控制模型。该模型实现对Web服务的消息级访问控制,并且具有良好的扩展性,能够通过对消息处理链的扩展使模型满足不同的访问控制要求。结合一个实际应用场景,描述XFire框架下的模型实现。     

基于XACML的访问控制策略

如何解决对Web服务的访问控制已成为当前Web服务应用研究中的一个重要课题。首先介绍了XACML标准的产生动机,然后结合Xpath来说明如何定义标准的访问控制策略。应用XACML策略来定义通用的访问控制需求,并且提出了一种机制来发现和解决策略间的冲突,达到对Web服务进行细粒度的访问控制。最后以一个应用实例来具体描述怎样创建一个XACML访问控制策略以及如何对实体的访问进行控制。     

Web服务访问控制规范及其实现

提出了一种用于Web服务的访问控制模型,这种模型和Web服务相结合,能够实现Web服务下安全访问控制权限的动态改变,改善目前静态访问控制问题。新的模型提供的视图策略语言VPL用于描述Web服务的访问控制策略。给出了新的安全模型和Web服务集成的结构,用于执行Web服务访问控制策略。     

Web服务协同环境下个性化访问控制框架的实现

根据Web服务的协同环境下个性化访问控制的特点,提出了一个利用Web服务的消息中间件机制来建立一个访问控制框架,并配合扩充了的RBAC-3访问控制模型,实现对Web服务的个性化访问控制。最后还给出了测试与优化的结果。     

Web服务访问控制的设计和实现

为实现Web服务的安全访问,利用SSL传输SOAP报文的Web服务安全机制只考虑点到点的通信,不能实现端到端的通信,并且不能对报文的局部进行加密的弊端,在分析WS-Security开源代码WSS4J的基础上,设计了一套基于SOAP报文处理的Web服务访问控制的安全模型.利用SOAP报文处理器实现Web服务报文的安全,利用访问控制机制实现Web服务的授权处理,并在java平台上给出了对SOAP报文进行扩展的方法,对此安全模型进行了测试.此模型实现了SOAP报文的安全通信并阻止了相关资源被非法访问.     

基于SAML和XACML的Web服务访问控制模型

Web服务采用了通用的协议和技术,便于用户访问,已成为了分布式计算的研究热点,但这种方便也带来了安全性的隐患。提出了一个基于SAML和XACML的Web服务访问控制模型,利用SAML协议实现单点登录,采用XACML策略描述语言对用户进行访问控制。模型在扩展SAML协议的基础上,把XACML引入Web服务能够更好地对服务端受保护资源进行控制,从而实现Web服务的安全访问控制。     

基于角色的Web Services动态访问控制模型

已有模型对Web Services的访问控制多数是静态的、粗粒度的,不能满足动态的面向服务的Web Services环境。为此提出了一个基于角色的Web Services动态访问控制模型(RBDAC),此模型可以根据用户访问时的上下文信息来激活角色分配和权限分配,并动态地做出访问控制决定。     

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.