基于中间件的Web服务和网格服务混合合成

随着Web服务和网格服务数量急剧增加,通过agent协作的两种服务混合合成却无法解决从安全性到事务处理等问题。本文利用中间件技术,对Web服务和网格服务混合合成框架进行了扩展;并利用面向方面的方法灵活了服务的合成。最终解决了Web服务和网格服务混合合成中安全性、可靠性、一致性、动态性等问题。     

网格环境下基于实体行为的动态信任评估模型

信任管理作为网格研究的核心内容,受到研究人员的高度关注。目前提出的诸多信任评估模型都基于实体身份,本文首先描述了基于实体行为的信任和信誉定义,在此基础上,基于被评估者的行为给出了一个动态信任评估模型。最后通过仿真实验对模型进行了验证,得到了相应的实验结果和结论。     

A new skeletal model for fabric drapes

Fabric drapes are typical large displacement, large rotation and small strain problems. Compared with continuum shell finite element methods, methods that skeletonize the fabric sheet into a set of interconnected nodes appear to be more popular in drape problems with extensive wrinkles. These skeletal methods may resort to particle mechanics and formulate the elastic energy or the equations of motion in terms of the node-to-node distance and the angles between the straight lines joining adjacent nodes. Alternatively, beam elements can be employed to skeletonize the fabric sheet at the expense of using rotational in addition to translational nodal DOFs. In this paper, a new skeletal model based on the small strain and curvature assumptions is devised. In contrast to most, if not all, skeletal models for fabric drape simulation, all the stretching, shearing and bending energies in the model are simple polynomials of the grid-point␣displacement. Fabric drape problems with extensive wrinkles are examined. The presence of sharp fold, seam and cut in the undeformed fabric sheet as well as fabric-to-solid contact are considered. The predicted appearances are pleasant and conform to real life observations.     

A Flexible Framework for Fault Tolerance in the Grid

This paper presents a failure detection service (FDS) and a flexible failure handling framework (Grid-WFS) as a fault tolerance mechanism on the Grid. The FDS enables the detection of both task crashes and user-defined exceptions. A major challenge in providing such a generic failure detection service on the Grid is to detect those failures without requiring any modification to both the Grid protocol and the local policy of each Grid node. This paper describes how to overcome the challenge by using a notification mechanism which is based on the interpretation of notification messages being delivered from the underlying Grid resources. The Grid-WFS built on top of FDS allows users to achieve failure recovery in a variety of ways depending on the requirements and constraints of their applications. Central to the framework is flexibility in handling failures. This paper describes how to achieve the flexibility by the use of workflow structure as a high-level recovery policy specification, which enables support for multiple failure recovery techniques, the separation of failure handling strategies from the application code, and user-defined exception handlings. Finally, this paper presents an experimental evaluation of the Grid-WFS using a simulation, demonstrating the value of supporting multiple failure recovery techniques in Grid applications to achieve high performance in the presence of failures.     

基于Dividing Cubes的算法实现螺旋CT数据的三维重建

为了提高Dividing Cubes算法的绘制速度，结合螺旋CT扫描数据的特点，提出了一种改进的快速三维表面绘制方法。通过利用体元的特点和体元间的相互关系，对体元进行了特殊的处理，大大提高了三维重建的速度。     

网格监控系统研究

The monitoring system is very critical for complex and large high-performance distributed system such as a Grid. With the help of a monitoring system the users and developers of a Grid can perform tasks such as fault-detec-tion and diagnosis, performance analysis and tuning and performance prediction. And a good monitoring system can give useful data to the scheduling module of the Grid. This paper gives a detailed presentation and analysis of the key techniques of a grid monitoring system, and points out the research directions of the grid monitoring system based on current research around the world.     

一种面向电冰箱测试的计算机网格系统

介绍了一种电冰箱测试计算机网格系统。利用该网格系统，把企业遍布在全国、分布在Internet上的各电冰箱测试系统，整合为一台虚拟计算机上的电冰箱测试系统，实现整个企业冰箱测试的统一监控、查询、统计分析，为企业冰箱质量的宏观控制提供可靠依据，给电冰箱生产相关企业提供了一种计算机网格应用模型。     

网格计算的研究新进展

网格计算诞生了一个全新的领域,它以大规模的资源协作共享、创新的应用以及高性能计算的特点,区别于传统的分布式计算。文章简述了网格计算的定义、特点、功能和基本体系结构,重点综述了网格的研究新进展及其商业化应用前景,分析了当前网格研究的发展趋势及其我国的对策。     

基于Agent网格计算性能的实时调节

由于网格环境中资源的动态性、非独占性、异构性、分布性和网络通信延迟的不确定性等因素导致了应用程序的复杂和低效,难以达到预期的性能。为了实时调整和改进并行和分布式应用的性能,该文研究采用Agent技术设计一种系统模型,利用Agent收集应用各种性能参数,然后利用Agent的智能性,加以分析综合并实时调整,使应用程序更加适应网格的动态环境,获得更高的性能。     

网格技术框架的探讨和研究

介绍了网格计算的概念，描述了在虚拟组织环境中的网格技术的层次框架，重点探讨了每一层的作用和功能，最后通过实例进行了具体的阐述。