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1.
对于开发系统内涵的澄清   总被引:4,自引:2,他引:2  
虽然开放系统是一个流行的名词,但是对于一般用户,它却是一个在实际中“无法操作”的事物。本文从计算机开放系统的基本特征出发,通过逻辑推导,导出描述开放系统的轮廓,借助于后者使开放系统一词的内涵得到了澄清,并使它的实现变成了“可操作的”文中人IT实际方便出发,提出了一个简明的开放系统的工作定义。  相似文献   

2.
开放系统已经成为当今计算机界广泛倡导并积极遵循的策略。从开放系统的基本特征出发,导出描述开放系统的轮廓框架(AUSPICE),通过对轮廓中各个组成部分,选用一定的标准就可以实现一个开放系统。但实现一个完全的开放系统是一个长期的过程,而且对于具体应用环境和需求.其实现过程各有不同。本文针对普适计算环境,首先分析了开放性对于普适计算环境的重要性和必然性,同时针对普适计算环境的特点,对开放系统的轮廓框架扩充为AUSPICAE,最后提出了适合普适计算环境的开放系统实现过程模型。  相似文献   

3.
本文从开放系统应具备的特征出发,提出研究制定现场总线OSI参考模型的原则。根据该原则,阐述了一个由控制面、用户面、管理面组成的现场总线开放系统互连参考模型。  相似文献   

4.
本文从协作学习的概念出发,用系统论的观点阐述协作与系统两者之间的关系。协作学习系统是一个开放的非线性系统,具有开放系统的特征;另外,协作学习中小组成员之间的相互关系、相互作用凸现了它的整体性特征。由此决定了协作学习是一个充满活力的动态发展的过程。  相似文献   

5.
对于包含动作精化的实时进程代数,人们已经为它定义了指称真并发语义。在这种语义里,动作精化被看作是一个操作符。人们自然会有这样的疑问:既然已经定义了指称真并发语义,为什么还要定义操作语义?这个问题可以从以下两个方面回答:首先,对于不带时间变量和动作精化操作的进程,为它赋予一个“标准”语义的含义就是指为它定义一个操作语义。定义操作语义常用的方法是定义一个具有标记的传递系统,它是由一些推理规则组成的集合,这些推理规则刻画了实际程序或系统  相似文献   

6.
开放系统与系统集成   总被引:1,自引:0,他引:1  
《软件世界》1996,(9):30-32
对开放系统的理解 九十年代是一个开放的时代,然而何谓开放,却是一个相当模糊的概念,至少在计算机领域是如此。业界所谈到的开放系统一般特指以UNIX为操作系统的一类系统。何以要由UNIX独享开放尊荣?是否还有其它的开放系统?深究起来,其实大有文章。 笔者颇为赞同美国一位开放系统专家的观点。 首先应当指出的是,开放系统并非一个技术术语,而是一个市场概念。我们很难从技术角度划分开放系统与专有系统的本质区别,但是从市场策略上,则可以很清楚地看到开放与专有的市场策略的不同。 典型的开放系统市场策略,需要完成四方面的工作:  相似文献   

7.
“开放系统”概念提出五年以来,开放系统工业界经历了从单纯提供技术到用产品占颁市场、从实验技术到成熟工业的发展过程.目前.以UNIX操作系统为主流和代表的开放系统产品已经覆盖了从克雷大型机到膝上机的各种机型.90年代,开放系统仍然是软件界的主导方向.目前UNIX业界正在实践的标准化运动标志着开放系统时代的到来.  相似文献   

8.
本文是“开放系统”系列文章的第二篇,阐述开放系统产生的背景,评述开放系统的演进过程,揭示开放系统 成为九十年代计算机行业发展总趋势的必然性。  相似文献   

9.
《Windows网络服务器架构》是计算机网络专业核心课程,也是一门专业技能实训课。它要求对“网络服务器”具备“规划、安装、配置和管理”等“岗位技术能力”。本文从网络技术职业实际岗位的完整工作过程出发,结合职业院校学生的特点和培养目标,进行分析与研究,探索基于工作过程的《Windows网络服务器架构》课程建设方案。  相似文献   

10.
OS、OSI、OSIE     
OS(Opeo System)——开放系统。是按照开放的接口、服务和支持格式规范而实现的系统。它能使应用软件以最少的修改,实现在不同系统中的移植,能同本地或远程中的应用实现相互操作,以方便用户以迁移的方式交互。开放系统具有可移植性、相互操作、交换一致性。  相似文献   

11.
开放分布式处理及其实例   总被引:1,自引:0,他引:1  
汲化  陈军 《计算机科学》1996,23(1):27-31
迅速发展的计算机与通信技术使得构造大型分布式系统成为可能,尽管如此,互连系统特别是  相似文献   

12.
Coding no longer represents the main issue in developing software applications. It is the design and verification of complex software systems that require to be addressed at the architectural level, following methodologies which permit us to clearly identify and design the components of a system, to understand precisely their interactions, and to formally verify the properties of the systems. Moreover, this process is made even more complicated by the advent of the “network-centric” model of computation, where open systems dynamically interact with each other in a highly volatile environment. Many of the techniques traditionally used for closed systems are inadequate in this context.We illustrate how the problem of modeling and verifying behavioural properties of open system is addressed by different research fields and how their results may contribute to a common solution. Building on this, we propose a methodology for modeling and verifying behavioural aspects of open systems. We introduce the IP-calculus, derived from the π-calculas process algebra so as to describe behavioural features of open systems. We define a notion of partial correctness, acceptability, in order to deal with the intrinsic indeterminacy of open systems, and we provide an algorithmic procedure for its effective verification.  相似文献   

13.
Towards an open architecture for vector GIS   总被引:4,自引:0,他引:4  
A range of open source software tools are now available to the Geographical Information Systems (GIS) analyst. However these tools are not necessarily interoperable and rarely significantly interoperable with proprietary systems. The open architectures, which have been developed for web-oriented systems, together with those proposed by the Open Geospatial Consortium (OGC), suggest that an open GIS architecture could be developed as an alternative to proprietary systems. The architecture would use open source components to store, translate, analyse, render and visualise GI data and would escape many of the problems of monolithic systems. Particularly what is proposed permits the loose coupling of any number of components and data stores in a manner that is both open and flexible. This paper proposes such an architecture and focuses on determining the suitability of Scalable Vector Graphics (SVG), an open vector-oriented eXtensible Markup Language (XML) grammar, as a significant component of such architecture. SVG is shown as an effective means of rendering GI data, not least because of its compatibility with the WC3 Document Object Model (DOM), permitting GIS-specific client tools to be written and transmitted to the web browser along with the SVG pages. While realising that the technology is in its infancy, the conclusion reached is that SVG currently provides a powerful solution and has enormous future potential.  相似文献   

14.
开放系统中互操作技术的发展和前景   总被引:7,自引:1,他引:6  
经历九十年代的持续实践,采用“开放系统”的思想来集成大型计算机系统,已成为技术界不争的事实。然而,完善的开放系统的实际形成有赖于“互操作性”的实现。本文将以互操作性为对象,探讨近十年来人们对其认识的深化,为有关挑战性难题所作的突破,以及未来发展的前景。  相似文献   

15.
As opposed to closed systems, the state dynamics of open systems are additionally determined by independently acting external forces called "environment" in ecology. Ecosystems are open dynamical systems whose stability characteristics are commonly described in terms of resistance and resilience of system states towards the “disturbing” effects of external forces. The implicit ideas of invariance and attractivity of specific system states, however, are borrowed from the stability theory of closed dynamical systems and are therefore of limited utility for comprehensive representations of stability characteristics in open dynamical systems. Based on a generic formulation of dynamical input-output systems, it is demonstrated that the notion of adaptation of a system's responses (outputs) to its environment (inputs), when quantified by adaptational valuation functions, provides formulations which establish the desired extension of the ideas of stability known from closed systems. In essence, stability can then be viewed as a system's capacity to immediately or ultimately realize adapted responses. This capacity can conveniently be described for example with the aid of adaptational potentials of system states as described by the set of environments to which adaptation is possible. Regulatory and structural adaptation, which are the two forms of adaptation taking place without and with changes in system state, respectively, are shown to imply a natural hierarchy in adaptational processes. It is suggested that the involved levels of hierarchy be viewed to represent a mechanism for preserving adaptability in ecosystems, which in turn constitutes one of the most crucial components of ecosystem stability.  相似文献   

16.
研究了开放环境下多比特量子计算系统的相干控制建模问题.基于开放量子系统的数学模型,选取适当的矩阵基将描述多比特量子计算机的复矩阵动态控制模型转化为实向量空间上的控制模型,并给出计算相应的结构系数的方法.这些工作提供了进一步研究控制律设计的基础.  相似文献   

17.

Background

The use of open source software in health informatics is increasingly advocated by authors in the literature. Although there is no clear evidence of the superiority of the current open source applications in the healthcare field, the number of available open source applications online is growing and they are gaining greater prominence. This repertoire of open source options is of a great value for any future-planner interested in adopting an electronic medical/health record system, whether selecting an existent application or building a new one. The following questions arise. How do the available open source options compare to each other with respect to functionality, usability and security? Can an implementer of an open source application find sufficient support both as a user and as a developer, and to what extent? Does the available literature provide adequate answers to such questions? This review attempts to shed some light on these aspects.

Objective

The objective of this study is to provide more comprehensive guidance from an implementer perspective toward the available alternatives of open source healthcare software, particularly in the field of electronic medical/health records.

Methods

The design of this study is twofold. In the first part, we profile the published literature on a sample of existent and active open source software in the healthcare area. The purpose of this part is to provide a summary of the available guides and studies relative to the sampled systems, and to identify any gaps in the published literature with respect to our research questions. In the second part, we investigate those alternative systems relative to a set of metrics, by actually installing the software and reporting a hands-on experience of the installation process, usability, as well as other factors.

Results

The literature covers many aspects of open source software implementation and utilization in healthcare practice. Roughly, those aspects could be distilled into a basic taxonomy, making the literature landscape more perceivable. Nevertheless, the surveyed articles fall short of fulfilling the targeted objective of providing clear reference to potential implementers. The hands-on study contributed a more detailed comparative guide relative to our set of assessment measures. Overall, no system seems to satisfy an industry-standard measure, particularly in security and interoperability. The systems, as software applications, feel similar from a usability perspective and share a common set of functionality, though they vary considerably in community support and activity.

Conclusion

More detailed analysis of popular open source software can benefit the potential implementers of electronic health/medical records systems. The number of examined systems and the measures by which to compare them vary across studies, but still rewarding insights start to emerge. Our work is one step toward that goal. Our overall conclusion is that open source options in the medical field are still far behind the highly acknowledged open source products in other domains, e.g. operating systems market share.  相似文献   

18.
陈亚亚  王乘 《微机发展》2005,15(10):113-115,119
概述了开放式数控系统,尤其是开放式软数控的发展现状与特点;分析和构建了基于数控虚拟机的开放式数控系统的体系结构,介绍了此系统中的软/硬件结构;在对具有代表性的操作系统进行了研究与比较之后,选择了Linux作为此系统的软件开发平台;最后根据Linux内核的结构特点,重新划分了传统用户模式下运行的数控软件体系,建立了包含实时控制层和数控应用层的双层模型,就其中的关键性技术问题进行了探讨和分析,明晰了该虚拟机在Linux下的具体实现方法。  相似文献   

19.
To apply time-varying port-controlled Hamiltonian (PCH) systems to practical control designs, two basic problems should be dealt with: one is how to provide such time-varying systems a geometric structure to guarantee the completeness of representations in mathematics; and the other is how to express the practical system under consideration as a time-varying PCH system, which is called the dissipative Hamiltonian realization problem. The paper investigates the two basic problems. A suitable geometric structure for time-varying PCH systems is proposed first. Then the dissipative realization problem of time-varying nonlinear systems is investigated, and serval new methods and sufficient conditions are presented for the realization.  相似文献   

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