基于DSP多处理器实时开发环境的设计

基于DSP的实时开发环境一般都是针对单独处理器进行开发而设计的,当一个系统中使用了多种类型的DSP芯片时.往往无法同时使用这些开发环境,也就无法进行系统级开发.本文通过研究提出了一种多处理器实时开发环境的设计思想.它可以支持多种型号处理器的同时开发,使系统级开发变得简单易行.这种统一的软件开发环境使开发人员始终面向同一个开发环境,易学易用,提高了开发效率.     

A design flow for supporting component-based software development in multiprocessor real-time systems

Component-based software development established as an effective technique to cope with the increasing complexity of modern computing systems. In the context of real-time systems, the M-BROE framework has been recently proposed to efficiently support component-based development of real-time applications on multiprocessor platforms in the presence of shared resources. The framework relies on a two-stage approach where software components are first partitioned upon a virtual multiprocessor platform and are later integrated upon the physical platform by means of component interfaces that abstract from the internal details of the applications. This work presents a complete design flow for the M-BROE framework. Starting from a model of software components, a first method is proposed to partition applications to virtual processors and perform a synthesis of multiple component interfaces. Then, a second method is proposed to support the integration of the components by allocating virtual processors to physical processors. Both methods take resource sharing into account. Experimental results are also presented to evaluate the proposed methodology.     

Specification of realtime systems using ASTRAL

ASTRAL is a formal specification language for real-time systems. It is intended to support formal software development and, therefore, has been formally defined. The structuring mechanisms in ASTRAL allow one to build modularized specifications of complex systems with layering. A real-time system is modeled by a collection of state machine specifications and a single global specification. This paper discusses the rationale of ASTRAL's design. ASTRAL's specification style is illustrated by discussing a telephony example. Composability of one or more ASTRAL system specifications is also discussed by the introduction of a composition section, which provides the needed information to combine two or more ASTRAL system specifications     

多媒体课件开发平台软件环境的分析比较

当今世界,教育信息化是教育现代化的一个重要方向.CAI技术又是推进教育信息化的重要手段之一.作者根据近年来制作多媒体课件取得一些经验的基础上,对目前比较流行的几种多媒体课件开发平台的软件环境,包括编辑电子讲稿的PowerPoint软件,编辑光盘课件的Authorware和Director软件,编辑网络课件的ASP、PHP和JSP网页编辑和运行环境,以及编辑网络流媒体课件的Flash软件的性能特点、相关技术、实现难度、学习难度、适用场合等作了分析比较,并对它们的优势和局限给出了明确的结论,可供有兴趣制作多媒     

Specifics of development of software systems for real-time pattern recognition

Requirements to systems for real-time pattern recognition are formulated. An approach to organization of the software system for real-time pattern recognition and evaluation of system effectiveness is proposed.     

Experimental evaluation of software development tools for safety-critical real-time systems

Since the early years of computing, programmers, systems analysts, and software engineers have sought ways to improve development process efficiency. Software development tools are programs that help developers create other programs and automate mundane operations while bringing the level of abstraction closer to the application engineer. In practice, software development tools have been in wide use among safety-critical system developers. Typical application areas include space, aviation, automotive, nuclear, railroad, medical, and military. While their use is widespread in safety-critical systems, the tools do not always assure the safe behavior of their respective products. This study examines the assumptions, practices, and criteria for assessing software development tools for building safety-critical real-time systems. Experiments were designed for an avionics testbed and conducted on six industry-strength tools to assess their functionality, usability, efficiency, and traceability. The results some light on possible improvements in the tool evaluation process that can lead to potential tool qualification for safety-critical real-time systems.     

夹点计算分析软件的设计与开发

针对换热网络系统能量计算工作量繁杂且准确计算夹点位置困难的问题,根据操作型央点计算的原理,采用单一传热温差法和虚拟温度法计算换热网络的夹点信息,运用问题表格法进行央点计算,确定灾点位置,用Vb6.0设计开发了通用于换网设计和改造的夹点分析计算软件.该软件对常规换网(系统存在一个夹点)、多夹点换网和门槛问题(threshold problem)均能准确分析计算.能计算识别是否门槛问题,判断其是加热或冷却公用工程并计算负荷值;对多夹点换网,显示最小温度夹点信息.通过3个问题表格将换网信息输出,绘制总组合曲线,提高了换热网络能量分析的效率和准确性.节省人量时间和人力,但随网络复杂程度手工输入物流参数工作量增大.对文献实例和某常减压换热网络夹点计算分析均取得满意结果.     

The case for electric design of real-time software

G. Booch (see ibid., vol.SE-12, no.2, p.211-21, Feb. 1986) has analyzed a problem involving the software of a set of free-floating buoys. The correspondence points out that Booch's analysis fails to address one important system issue, namely the fact that the software must support two concurrent activities, and shows that an analysis according to the M.A. Jackson method will reveal this difficulty at an early design stage. On the other hand, the Jackson approach does not deal with some configuration issues, which are handled in Booch's analysis. This shows that one method is sometimes not enough to address all important, systemwide aspects of a problem. Rather than arguing about which one design method is best, the author recommends taking an electric view and using any combination of approaches that yields important results in a given situation     

Flow: A software development environment using diagrams

The multiuser software development system FLOW uses a diagrammatic language, FLOW-DL, to represent the system under development. Once a module has been keyed in, one of three post-processors is called to generate source code in Pascal, Fortran, or Cobol. A fourth post-processor generates documentation. The system also includes a syntax-directed editor, as well as a software production data base which holds the FLOW-DL source code, interface data relating to the program modules, and control information pertaining to the state of the system under development. The package is portable; a graphics terminal is not required. Versions of the production system have been used for the past 4 years to develop a number of medium-sized software systems.     

Supporting software quality in an integrated safety-critical systems development environment

Research is described, aimed to support traceability in the design of software for safety-critical applications, through the provision of an on-line design journal enabling design decisions and actions to be traced and recorded. The design environment, within which various software design tools may be encapsulated, enables protocol between the user and the design tools to be trapped. This provides software engineering support at the conceptual design stage. An important aim of the research is to enable inferences to be made from the captured protocol, for which the application of artificial intelligence methods is being investigated.     

An environment for integrated development and evaluation of real-time distributed database systems

Real-time database systems must maintain consistency while minimizing the number of transactions that miss the deadline. To satisfy both the consistency and real-time constraints, there is the need to integrate synchronization protocols with real-time priority scheduling protocols. One of the reasons for the difficulty in developing and evaluating database synchronization techniques is that it takes a long time to develop a system, and evaluation is complicated because it involves a large number of system parameters that may change dynamically. This paper describes an environment for investigating distributed real-time database systems. The environment is based on a concurrent programming kernel that supports the creation, blocking, and termination of processes, as well as scheduling and interprocess communication. The contribution of the paper is the introduction of a new approach to system development that utilizes a module library of reusable components to satisfy three major goals: modularity, flexibility, and extensibility. In addition, experiments for real-time concurrency control techniques are presented to illustrate the effectiveness of the environment.This work was supported in part by ONR contract # NOOO14-88-K-0245, by DOE contract # DEFG05-88-ER25063, by CIT contract # CIT-INF-90-011, and by IBM Federal Systems Division.     

Supporting model-driven development using a process-centered software engineering environment

The adoption of Model-Driven Development (MDD) is increasing and it is widely recognized as an important approach for building software systems. In addition to traditional development process models, an MDD process requires the selection of metamodels and mapping rules for the generation of the transformation chain which produces models and application code. In this context, software process tasks should be performed in a specific sequence, with the correct input artifacts to produce the output ones. However, existing support tools and transformation engines for MDD do not have a process-centered focus that addresses different kinds of software process activities, such as application modeling and testing to guide the developers. Furthermore, they do not enable process modeling nor the (semi) automated execution of activities during process enactment. The MoDErNE (Model Driven Process-Centered Software Engineering Environment) uses process-centered software engineering environment concepts to improve MDD process specification and enactment by using a metamodeling foundation. In MoDErNE, a software process model may be enacted several times in different software projects. This paper details the MoDErNE environment, its approach and architecture and also the case studies through which the tool was evaluated.     

Evaluating software architectures for real-time systems

In this paper we describe a process for evaluating the architectures of large, complex software-intensive systems. This process involves both social and technical aspects. The social aspects deal with planning and running an evaluation. The technical aspects concentrate on the representation of architectural information, standard questions, analyses, and quality attribute characterizations. We then take the generic notion of architectural evaluation, and discuss some techniques for applying this technique to the domain of real-time systems. This revised version was published online in June 2006 with corrections to the Cover Date.     

Forecasting real-Time behavior during software design using a CASE environment

Real-time software is required to react within certain time constraints. Aimed at forecasting early during the design process whether the design approach chosen will fulfill those time constraints, while avoiding costly prototyping, two different methods have been developed: open-loop dynamic evaluation of time-critical parts of executable design specifications, and animating a closed-loop system, consisting of the executable design specifications, coupled to a dynamic simulation model of the physical system involved. Both methods are explained using examples.     

Generating code for engineering design systems using software patterns

We illustrate here how software engineers developing engineering design systems can introduce patterns into the conceptual modeling techniques that were developed in the database community and integrate them with techniques that are emerging in the object-oriented analysis and engineering design community. The goal is to raise the level of abstraction used to communicate software specifications and to build applications. This will speed the development and improve the quality of engineering design tools. We show by an example how this can be accomplished through an example software pattern from the software engineering discipline (the observer pattern) [12]. We show how patterns can be automatically supported using the general techniques that were developed in the Semantic Objects, Relationships, and Constraints (SORAC) project [20] for the development of tools, for the specification of databases and for building design systems.     

游戏型教学软件的设计与开发

游戏型教学软件在设计时应注重教学过程的趣味性,尊重学习者的主体性,将教学内容放在游戏情境中进行展现,让学习者在充满趣味性和挑战性的氛围中学习,轻松愉快地掌握相关知识和技能,从而提高学习质量.目前,我国游戏型教学软件的数量少,质量也存在一些问题.结合相关理论和实例,论述了游戏型教学软件设计的原则、方法及过程.     

间歇精馏设计软件的开发

利用Visual Basic 6.0语言开发间歇精馏常规设计及优化设计软件。软件可用于不同物系(二元理想及非理想溶液),采用不同操作方式(恒馏出液组成操作和恒回流比操作)间歇精馏的常规设计和优化设计(包括单变量优化和多变量优化)计算。软件采用面向对象的编程技术,对精馏组分的物性参数、汽液相平衡数据实行数据库操作,界面友好,使用方便。