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1.
基于网格技术提出了时移电视服务系统(GridTVOD,Time-shifted TV on demand based on grid).在GridTVOD系统中,系统组织基于Globus MDS,将视频服务器和服务节点组织为流媒体服务网格,视频数据传输采用P2P和Patching相结合,用户作为网格节点,在享受服务时,也作为服务端为其它节点提供服务.整个系统具有如下特点:1)采用流合并机制,有效地减少媒体服务器提供的基流数;2)采用分布式控制协议,系统具有良好的可扩展性;3)利用网格技术,为系统组织提供安全、有效的保障.  相似文献   

2.
分析了FTP服务的原理和缺点,给出了一个基于网格的校园FTP系统的设计模型.采用Globus Toolkit的MDS和Grid FTP这两个组件实现了网络资源监测和发现以及网格数据传输机制.  相似文献   

3.
李东阳  陈靖  黄聪会 《计算机工程与设计》2012,33(6):2502-2505,2515
为了从数据网格大量分布、多样、异构的资源中发现合适可用的数据资源.提出了基于网格中间件Globus Toolkit4.0中MDS组件的解决方法.在MDS中内嵌了7种Information Provider,它们只提供计算资源信息,不能提供如数据库、数据文件等数据网格资源信息.针对这个不足,利用MDS良好的可扩展性,设计了一个数据网格资源发现系统,并用Java语言并开发了支持数据网格资源信息的Information Provider.测试结果表明该方法有效可行.  相似文献   

4.
为网格提供一种可扩展的机制去监控网格中的资源信息是至关重要的,文章介绍了网格的监控对象、监控事件及数据的产生,分析讨论了GMA和MDS这两种常用的网格监控体系结构,前者是一个理论上的模型,后者则是已获得广泛应用的Globus工具集中的一个重要的信息服务监控组件。  相似文献   

5.
为网格提供一种可扩展的机制去监控网格中的资源信息是至关重要的,文章介绍了网格的监控对象、监控事件及数据的产生,分析讨论了GMA和MDS这两种常用的网格监控体系结构,前者是一个理论上的模型,后者则是已获得广泛应用的Globus工具集中的一个重要的信息服务监控组件。  相似文献   

6.
本文以传统的FTP服务方式为基础,分析了FTP服务的原理和缺点,给出了一个基于网格的校园FTP系统的设计模型。采用Globus Toolkit的MDS和GridFTP这两个组件实现了网络资源监测和发现以及网格数据传输机制。  相似文献   

7.
AnyQuery是一种适用于网格环境、基于服务的分布式查询处理系统,使用统一的数据格式(可扩展标记语言)来表示和传输数据,所有组成模块以网格服务的形式实现,网格服务之间通过标准的接口进行通信.这种接口和实现分离技术屏蔽了不同数据库及其运行节点的差异,为用户提供一致的虚拟关系数据视图和分布式数据查询支持.在分析和研究已有的并行数据库和分布式数据库查询技术的基础上,AnyQuery提出和实现了一种适用于动态网格环境的分布式查询计划生成和执行算法,该算法能够根据网格环境中各节点及其连接网络的实际情况确定查询计划,支持跨数据库的连接查询.基于Globus 3.0开发了AnyQuery的原型系统,性能测试表明该系统具有较好的可扩展性,尤其适合计算密集型的复杂查询.  相似文献   

8.
基于Globus的网格信息归档服务   总被引:2,自引:0,他引:2  
分析当前网格监控信息服务的不足,针对基于历史状态数据的应用需求,提出一种面向Globus的信息归档服务。在MDS聚合框架的基础上,设计2种状态信息获取方法,给出监控信息的数据存储结构。测试结果表明,该服务可以简化基于网格监控信息的系统开发。  相似文献   

9.
基于软件代理的网格信息服务   总被引:1,自引:0,他引:1  
计算网格允许对地理域上分散的资源进行大范围的、深入的、一致的共享。它们的固有属性将发现处于不同行政区域的资源和预测资源的性能并监控其行为的事务进行合并。监控和发现服务MDS(Monitoring and Discovery Service)是Globus工具集提供的一项主要服务,它可以用于为已存在的基于代理的资源发布和发现系统提供网格信息服务。给出一个代理系统,它使用MDS中的网格信息协议GRIP(Grid Information Protocol)和网格注册协议GRRP(Grid Registration Protocol)去发现虚拟组织并监控相关资源,使得此系统具有资源代理、监控及性能预测的作用。  相似文献   

10.
作为事实上的网格基础平台,Globus提供了网格系统的基础服务和API函数.在Globus的基础上进行网格服务开发是当前开发网格应用系统的主要手段.该文研究了在网格环境下网格服务的运行机制和开发过程,并进行了具体的实例开发.  相似文献   

11.
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.  相似文献   

12.
European Community policy and the market   总被引:1,自引:0,他引:1  
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.  相似文献   

13.
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。  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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  相似文献   

17.
为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
基于复小波噪声方差显著修正的SAR图像去噪   总被引:4,自引:1,他引:3  
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。  相似文献   

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