Using interceptors to enhance CORBA

The integration of distributed computing and the object model leads to distributed object computing, in which objects rather than processes are distributed across multiple computers. A well-established standard for distributed object computing is the Common Object Request Broker Architecture (CORBA). Previously, you would have had to create-and enable the application to use-the components that provide such additional capabilities. Using these components requires specialized knowledge and understanding of problems outside the application domain. With the advent of interceptors-non-application components that can alter application behavior-you can enhance CORBA applications at runtime with components whose operation is transparent to both the application and the CORBA framework, modifying application behavior without modifying the application or the CORBA framework     

Using Java applets and CORBA for multi-user distributedapplications

The Java language environment, World Wide Web, and Common Object Request Broker Architecture are complementary software technologies, which when used together provide a powerful set of tools for developing and deploying multi-user distributed applications. We describe an approach to building reasonably sophisticated and easy-to-use client software as WWW-downloadable Java applets, which use CORBA to interact effectively with remote server software and thus coordinate and control access to a set of shared resources. We used this approach to reimplement a portion of an existing multi-user distributed application that had been built using the WWW Common Gateway Interface (CGI), then evaluated the differences between the two approaches. We found our method of combining Java applets and CORBA not only practical but in many ways superior to the widely used CGI approach, as well as to a conventional CORBA approach that does not exploit the WWW     

Bridging boundaries: CORBA in perspective

Applications that cross the boundaries of different computing machines, operating systems, and programming languages are increasingly the norm. As a result, the need for what might be called bridging technologies to develop software that works across heterogeneous environments has become more compelling. The Common Object Request Broker Architecture is one such technology that is both robust and commercially available. CORBA essentially describes how client applications can invoke operations on server objects using the services of an intermediary known as an Object Request Broker, or ORB. This article introduces CORBA by describing its key components. It then reviews the boundaries it helps to bridge. It concludes by comparing CORBA with a number of other bridging technologies available today     

基于自适应通信环境(ACE)的可移植异构分布平台进程间通信程序设计的研究

自适应通信环境（ＡＣＥ）是一个实现了并发通信软件的核心设计模式的、免费的、开放源代码的、面向对象软件框架。自适应通信环境（ＡＣＥ）提供了丰富的完成公共通信功能的、可重用Ｃ＋＋类包和框架组件,它可以运行于众多的平台。文章介绍了自适应通信环境（ＡＣＥ）的结构和功能,接着构建了一个用于实验的实用而低价位的异构网络计算环境,并在此环境下测试了ＡＣＥ的通信性能。然后着重探讨了如何基于ＡＣＥ在异构网络环境下设计可移植的进程间通信程序的问题,最后举了一对可移植的Ｃｌｉｅｎｔ／Ｓｅｒｖｅｒ程序的例子。     

面向因特网应用的容错和负载平衡管理

针对因特网应用的三层客户／服务器体系结构,本文设计并实现了一个面向冗余服务的管理系统ＯＭ。它采用分布对象技术,基于ＣＯＲＢＡ平台,为冗余服务提供了容错和负载平衡管理服务,同时它还为系统管理员提供了管理接口,为用户提供了对服务的透明访问机制。     

SOAP与CORBA集成探讨

用SOAP简单对象访问协议对CORBA分布式计算进行集成，可以解决目前CORBA系统无法在Web上提供完整服务、受防火墙制约等问题。介绍了一种SOAP与CORBA集成的解决方案：SCOAP(Simple CORBA Object Access Protocol)协议，并讨论了该协议的体系结构和关键技术。     

银河分布计算环境

分布式客户／服务器计算环境是90年代分布处理的主流计算环境．应用需求的发展使分布式客户／服务器计算环境面临许多新的技术问题，包括应用级系统集成问题、智能服务问题和支持协同工作问题等等．本文以银河分布式客户／服务器计算机系统YHCS为背景，讨论YHCS分布计算环境的构成及主要设计技术．该环境以系统集成技术为重点，在解决上述3个技术问题方面取得了重要进展．     

多元统计过程状态监测分布式系统的实现

过程监测与故障诊断是工业过程工程中的一项重要任务,是保证生产过程安全运行、提高生产率的重要环节。本文在分析各种监控系统的基础上,结合多元统计过程控制方法,提出并开发了一个基于CORBA技术的多客户端工业过程实时监测软件系统。该系统由数据采集、多元统计数据分析服务端、监测界面客户端三部分组成,采用开放式结构具有良好的易维护性和扩充性。     

Engineering information integration using object‐oriented mediator technology

The mechanical product development process uses many different software systems to virtually simulate the behaviour of a design. The present work deals with flexible and efficient integration using object‐oriented mediator technology that provides transparent access to distributed engineering systems. The use of mediator technology is investigated for semi‐automatically integrating engineering information resident in computer aided design systems with a Common Object Request Broker Architecture based application programming interface. The purpose is to provide engineering analysis applications access to computer aided design system information and computational methods through a declarative query language. We conclude that the use of a declarative query language for developing engineering applications shows great potential in terms of flexibility, development productivity, performance, and ease of use, compared with using a procedural programming language. The work also shows new use of mediator technology, declarative queries, and active rules within engineering information integration that traditionally is accomplished using procedural programming. Copyright © 2004 John Wiley & Sons, Ltd.     

The object-powered Web

The convergence of Web and object oriented technologies will allow applications to transcend conventional boundaries of platform, organizational function, enterprise, industry, and geography to leverage the power of distributed computing. For developers, this will mean the ability to use new or legacy code-possibly running on transcontinentally located machines-to build distributed, three tier client server applications. For end users, this will mean the ability to integrate information needs across and beyond the enterprise. For the computing world, this will mean applications that transcend conventional boundaries of platform, organizational function, enterprise, industry, and geography, leveraging the true power of distributed computing     

以XML文件为例实现在CORBA结构下对异质性数据的访问

该项目实现了一个CORBA/XMLWrapper，将XML文件包装成CORBA的ServerObject,让Client可通过调用Server Object提供的method访问到XML文件中的资料，并且在前台提供一个QBELike介面让用户查询XML文件内容，文章提供的方法可以扩展到CORBA结构下的各种关系数据库等异质性数据的访问。     

建立基于对象Web的三层分布式应用

CORBA为对象Web提供分布式对象计算平台。文章以会所管理系统为例讨论采用对象Web方法在Web方式下建立三层分布式应用的方法。     

CORBA技术在网络管理中应用的探讨

随着网络应用的发展,对网络管理系统的规模、服务的种类要求不断提高,分布式的网络管理系统成为一个重要的发展方向.同时,由于当前网络管理领域SNMP和CMIP协议同时存在的情况,如何把基于这两种协议的系统进行综合也成为研究的重点.作为对这些问题的一个很好的解决方案,CORBA这个分布式计算结构被逐渐应用到网络管理系统当中.文章对目前CORBA在网络管理中的应用情况进行了分析,并比较了不同实现方法的优缺点.     

基于CORBA的分布实时对象计算技术研究

随着网络化的日益普及,现有计算机系统面临着复杂和难以集成的问题．以ＣＯＲＢＡ为主流技术的分布对象计算技术简单有效地降低了非实时应用的复杂度和集成难度．但是,现有的ＣＯＲＢＡ规范无法支持分布实时环境,因此,有必要研究基于ＣＯＲＢＡ的分布实时对象计算技术．本文分析了现有ＣＯＲＢＡ的规范的实时特性缺陷,以作者设计的基于ＣＯＲＢＡ的分布实时对象软件ＯＲＢａｓｅ为例,介绍了基于ＣＯＲＢＡ的分布实时对象计算的     

G‐BLAST: a Grid‐based solution for mpiBLAST on computational Grids

Over the past few years, research and development in bioinformatics (e.g. genomic sequence alignment) has grown with each passing day fueling continuing demands for vast computing power to support better performance. This trend usually requires solutions involving parallel computing techniques because cluster computing technology reduces execution times and increases genomic sequence alignment efficiency. One example, mpiBLAST is a parallel version of NCBI BLAST that combines NCBI BLAST with message passing interface (MPI) standards. However, as most laboratories cannot build up powerful cluster computing environments, Grid computing framework concepts have been designed to meet the need. Grid computing environments coordinate the resources of distributed virtual organizations and satisfy the various computational demands of bioinformatics applications. In this paper, we report on designing and implementing a BioGrid framework, called G‐BLAST, that performs genomic sequence alignments using Grid computing environments and accessible mpiBLAST applications. G‐BLAST is also suitable for cluster computing environments with a server node and several client nodes. G‐BLAST is able to select the most appropriate work nodes, dynamically fragment genomic databases, and self‐adjust according to performance data. To enhance G‐BLAST capability and usability, we also employ a WSRF Grid Service Portal and a Grid Service GUI desk application for general users to submit jobs and host administrators to maintain work nodes. Copyright © 2008 John Wiley & Sons, Ltd.     

事件服务在CORBA/SNMP网关中的应用

作为新一代分布式计算规范的CORBA(公共对象请求代理体系结构),解决了异构环境下电信网络管理的难题,但如何利用CORBA技术来兼容原有电信网络成为各电信厂商亟需解决的问题。CORBA/SNMP网关就是解决此问题的一种经济、高效的办法。本文主要介绍了在CORBA/SNMP网关中,如何利用CORBA事件服务主动将设备故障、告警等紧急事件上报给管理者,以便管理者能及时处理的实际应用方案。     

CORBA负载平衡的研究

一、引言作为分布式计算的一个重要规范—CORBA,其主要目标是解决面向对象的异构应用之间的互操作问题,并提供了分布式计算所需的多项服务。ORB是CORBA平台的核心,它用于屏蔽与底层平台有关的细节,使开发者可以集中精力去解决与应用相关的问     

基于CSC的分布式应用对象交互服务模型DAOIS的研究

介绍一种新的分布式计算支撑模型与工具──分布式应用对象交互服务模型ＤＡＯＩＳ。它主要面向松散型的分布或独立应用系统的开发与集成。以ＣＳＣ为工作与构造模型,以平台级的、应用独立的、悬挂式的、网络透明平台透明应用代码透明的“软插件”为基础,辅以“包装”式的构造协议。     

Distributed object management integrating distributed information in heterogeneous environment

Organizations today need an optimized environment that builds and integrates diverse operating systems, hardware and applications. Distributed Computing provides us with a facility to transparently access all data, resources in the network. Current Research, projects that distributed object management concept along with the distributed computing environment can provide a single interface to manage the complexities of a heterogeneous environment. Using a uniform framework based on the DCE standard, we attempt to create an Object Oriented Distributed Computing Environment that will help us create open distributed applications with location independence for client applications in a multivendor network.

A better model for Open Distributed Computing aided by Object Oriented concepts is offered. Some of the research issues in realizing such a model are contemplated. We integrate an Object Manager with the OSF' DCE and discuss its benefits.     

On developing an inventory management system in the client/server environment

It is reported that client/server technology can make it easier for users to access information, to use and to develop applications, and to manage a distributed computing environment. This paper describes the implementation of client/server technology to an inventory management system. Methodology developed and barriers faced in this study are useful for practitioners in building client/server applications.