基于Java COG Kit的网格应用

CoG Kit作为网格技术与现有商业开发技术之间的桥梁，对网格计算的发展起了重要作用。而由Java语言本身的优势，Java CoG Kit得以重点开发。该文阐述了Java CoG Kit在网格应用中的作用，并以Climate Portal网格应用为例说明了如何使用Java CoG Kit访问网格服务     

Java CoG Kits在GridFTP开发中的应用

通过对Java CoG Kits软件包的研究,介绍了Java CoG Kits的结构和GridFTP的特性,讨论了Java CoG Kits中用于开发GridFTP客户端的FTP包的组件层次和类库,描述了GridFTP客户端类库用于编写GridFTP应用的函数,研究了GridFTP第三方控制数据传输模型,给出了实现的过程和步骤,最后基于Java CoG Kits设计实现了GridFTP第三方控制数据传输。     

Java CoG Kits在GridFFP开发中的应用

通过对Java CoG Kits软件包的研究,介绍了Java CoG Kits的结构和GridFTP的特性,讨论了Java CoG Kits中用于开发GridFrP客户端的FTP包的组件层次和类库,描述了GridFTP客户端类库用于编写GridFlP应用的函数,研究了GridFTP第三方控制数据传输模型,给出了实现的过程和步骤,最后基于Java CoG Kits设计实现了GridFTP第三方控制数据传输.     

Java CoG Kits在GridFTP开发中的应用

通过对Java CbG Kits软件包的研究,介绍了Java CoG Kits的结构和GridFTP的特性,讨论了Java CoG Kits中用于开发GridFTP客户端的FrP包的组件层次和类库,描述了GndFTP客户端类库用于编写GridFTP应用的函数,研究了GridFTP第三方控制数据传输模型,给出了实现的过程和步骤,最后基于Java CoG Kits设计实现了GridFTP第三方控制数据传输。     

网格环境中文件传输服务的研究与实现

论述了利用Java CoG Kit实现网格中的文件传输服务客户端的图形化界面,提供了高性能、可靠的网格环境中的文件传输服务,它具有支持基础安全机制、客户-服务传输、第三方控制传输等功能,剖析了GridFTP,详细介绍了基于网格环境中的文件传输服务实例。     

新闻播报

IBM日前成为国家863网格专项首家签约战略合作伙伴。在近日举行的签约仪式上,双方表示将在战略与系统综合研究、高性能计算机、网格结点、网格软件、应用网格等5个方面进行合作。同时,双方将深入合作推动网格计算在中国的各方面的发展,包括网格标准的制定,中国网格技术与国际间的交流,网格技术的开发及推广,网格应用的建立与普及等。863网格项目是大行业应     

网格模拟软件的发展现状及其模拟思想

阐述了在网格研发过程中模拟／仿真的重要性和必要性。介绍了当前较著名的网格模拟软件包Bricks,ChicSim,EDGSim．GridSim．MicroGrid,OptorSim和SimGrid已经实现了的网格模拟功能、实现这些网格模拟功能的思想和方法、开发语言、运行环境、应用实例、软件包是否可下载以及下载URL等,然后列表就功能、运行环境、配置方法、是否可视化等方面比较了这些软件包。最后总结这些网格模拟软件包的功能与其不足之处,并提出对网格模拟软件发展的一点看法。     

TITAN软件在网格中的服务构建研究

传统桌面遥感图像处理系统虽说功能日益强大且被广泛使用,但是这种集中式的软件缺乏有效的共享,从而限制了图像处理系统本身的发展。TITAN Image是我国自主研发的功能强大且算法新颖的优秀遥感图像处理软件,但它仍然是一个桌面遥感图像处理软件包。因此,利用网格开放式的资源共享模型,针对TITAN软件包的特点,研究了TITAN软件在空间信息网格中的服务构建方法。从而将TITAN软件包有机地整合到网格中,实现了图像处理算法的跨平台、跨区域的共享和互操作。     

自顶向下聚集型代数多重网格预条件的边权选择

针对基于图划分的自顶向下聚集型代数多重网格预条件,考察了利用METIS软件包进行多重网格构建的方法,并就该软件包只能处理整型权重,不能处理实型权重的问题,提出了一种将实型边权转化为整型边权的有效方法。之后将这种转化方法应用到METIS图划分软件中的边权选择,并用其给出了对自顶向下聚集型代数多重网格预条件的一种改进算法。通过对二维与三维模型偏微分方程离散所得稀疏线性方程组的数值实验表明,带边权的改进型算法大大提高了多重网格预条件共轭斜量法的迭代效率,特别是对各向异性问题,改进效果更加显著。     

应用Globus Toolkit实现网格服务

Globus对信息安全、资源管理、信息服务、数据管理以及应用开发环境等网格计算的关键理论和技术进行了广泛的研究,开发出能在多种平台上运行的网格计算工具包Globus Toolkit.此工具包能够用来帮助规划和组建大型的网格实验和应用平台,开发适合大型网格系统运行的应用程序.本文分析网格计算软件Globus Toolkit 3（GT3）的体系结构以及安装方法,然后以一个简单的网格计算为例在基于网格计算软件GT3的网格平台上实现网格服务.     

基于WSRF的Auction系统的关键技术研究

随着网格技术服务在基础体系结构方面的发展,如何将其与现实应用,电子商务等结合已经成为一个新的研究热点.本文对基于WSRF的Auction系统关键技术的探讨,不仅可以了解如何在WSRF和JAVA等标准平台下开发部署网格应用程序,同时可以进一步研究如何将网格和Web服务相结合,并将其应用到电子商务等方面中.     

网格服务创建方法及其在普适计算中的应用

通过研究普适应用对网格计算平台的内在需求,提出了在网格中创建大量瞬时服务以支持普适计算的理论与方法,给出了可重用的基本模块化网格服务的创建方法,包括构造标准化接口、抽象基本功能、部署运行时环境、集成应用系统以及在工程实践中设计瞬时服务的侧重点,并且在一个明确的网格工程背景下验证了该方法的简单、高效和安全性,瞬时服务随时随地可用,为用户提供了满意的服务.     

High path tracking control of an intelligent walking-support robot under time-varying friction and unknown parameters

Walking is the most fundamental requirement for independent living in daily life. An intelligent walking-support robot has been developed for use by people with walking disabilities. To appropriately assist the user, the robot must precisely track the user’s intentions. However, the robot’s tracking accuracy is severely compromised by time-varying friction, center-of-gravity (CoG) shifts, and load changes induced by the user. In a previous study, we proposed a digital acceleration controller with online inertial parameter identification. However, the tracking accuracy was still affected by CoG shifts introduced by the users. To address these issues, the current study investigated a novel dynamic model, wherein all the load and CoG information processed in the inertial matrix was derived and a new digital acceleration controller with parameter estimation was used to compensate for the time-varying friction, CoG shifts, and load changes. Experiments were conducted under different floor and load conditions to demonstrate the improved tracking accuracy of the proposed control method.     

适用于应用模式的网格结点选择方法研究

网格环境中的任务调度面临着海量的计算和通信资源环境,所以调度者需要考虑资源的选择问题.传统的资源选择方法一般只考虑计算能力或通信能力的最大化,没有考虑资源的通信模式与应用的匹配问题.本文在Remos研究的基础上,提出了一个完整的基于应用通信模式的网格结点选择算法.算法使用子图同构的辨识方法来判断网格结点的连通关系是否与应用模式相匹配,在满足通信模式约束的前提下,再用贪婪算法来选择计算和通信均较优化的结点.在通用算法的基础上,特别考虑了基于Master-Slave和All-to-All应用模式简化结点选择算法.最后,利用仿真方法,将本文的算法和随机选择法进行了比较,结果表明本文算法选择的网格结点不但满足应用的通信约束,而且性能较优.     

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.     

Mapping Abstract Complex Workflows onto Grid Environments

In this paper we address the problem of automatically generating job workflows for the Grid. These workflows describe the execution of a complex application built from individual application components. In our work we have developed two workflow generators: the first (the Concrete Workflow Generator CWG) maps an abstract workflow defined in terms of application-level components to the set of available Grid resources. The second generator (Abstract and Concrete Workflow Generator, ACWG) takes a wider perspective and not only performs the abstract to concrete mapping but also enables the construction of the abstract workflow based on the available components. This system operates in the application domain and chooses application components based on the application metadata attributes. We describe our current ACWG based on AI planning technologies and outline how these technologies can play a crucial role in developing complex application workflows in Grid environments. Although our work is preliminary, CWG has already been used to map high energy physics applications onto the Grid. In one particular experiment, a set of production runs lasted 7 days and resulted in the generation of 167,500 events by 678 jobs. Additionally, ACWG was used to map gravitational physics workflows, with hundreds of nodes onto the available resources, resulting in 975 tasks, 1365 data transfers and 975 output files produced.     

A novel compound biped locomotion algorithm for humanoid robots to realize biped walking

In this paper, a compound biped locomotion algorithm for a humanoid robot under development is presented. This paper is organized in two main parts. In the first part, it mainly focuses on the structural design for the humanoid. In the second part, the compound biped locomotion algorithm is presented based on the reference motion and reference Zero Moment Point （ZMP）. This novel algorithm includes calculation of the upper body motion and trajectory of the Center of Gravity （COG） of the robot. First, disturbances from the environment are eliminated by the compensational movement of the upper body; then based on the error between a reference ZMP and the real ZMP as well as the relation between ZMP and CoG, the CoG error is calculated, thus leading to the CoG trajectory. Then, the motion of the robot converges to its reference motion, generating stable biped walking. Because the calculation of upper body motion and trajectory of CoG both depend on the reference motion, they can work in parallel, thus providing double insurances against the robot＇s collapse. Finally, the algorithm is validated by different kinds of simulation experiments.