通信系统软件开发环境技术研究

通信系统的开发变得越来越复杂,各种技术侧重于系统开发的某个局部阶段,阻碍了这些技术的实际应用。该文从通信系统的特点出发,指出了开发这类系统的需求,分析了当前存在的技术对开发通信系统的支持,试图把这些方法统一到一个完整开发环境中。并从结构建模、行为建模、时间模型、系统验证和开发过程等几个方面重点分析了两类通信系统开发工具,指出某些存在的问题。最后进行总结并拟定了今后的研究重点。     

CRITON: A Hypermedia Design Tool

The WWW has turned into a development and run-time environment for large-scale and complex applications. Such sophisticated applications are being deployed in increasing numbers without having been developed according to appropriate methodologies, tools and quality standards. The reason is not only that the hypermedia industry resists to utilize formal methods, but also that these methods and corresponding tools are very few and of dubious standards. The consequence is that the hypermedia applications being developed are of poor functionality and lack qualities such as modifiability, usability and maintainability. Especially the design phase is one of the phases that lack sufficient support from methods and CASE tools. This paper presents CRITON, a cross platform tool, built to support a hypermedia design method within an integrated environment. CRITON manages all three aspects of hypermedia design: conceptual design, navigational design and graphical user interface design, utilizing well-established theories and practices from software as well as hypermedia engineering. It employs these designs to generate a preliminary, exemplary form of the hypermedia application for the purpose of assessing the designs before the implementation phase.     

CASE tool for microprocessing

Code Expert is ergonomic text editing software designed to help the user write programs for microprocessors. It runs on an IBM PC with PC-DOS, using popular microprocessor assembly languages and third-generation languages like c and PL/M. This tool has been used successfully in many realtime applications. It has been used, for example, to produce software based on algorithms (signal analysis and pattern recognition), to handle telecommunication (intelligent modem and emergency phone-call processing), and to perform data acquisition (power plant monitoring). Code Expert is introduced here in the context of CASE tools. An example application is given, followed by a discussion of the system's features.     

SUMLOW: early design‐stage sketching of UML diagrams on an E‐whiteboard

Most visual diagramming tools provide point‐and‐click construction of computer‐drawn diagram elements using a conventional desktop computer and mouse. SUMLOW is a unified modelling language (UML) diagramming tool that uses an electronic whiteboard (E‐whiteboard) and sketching‐based user interface to support collaborative software design. SUMLOW allows designers to sketch UML constructs, mixing different UML diagram elements, diagram annotations, and hand‐drawn text. A key novelty of the tool is the preservation of hand‐drawn diagrams and support for manipulation of these sketches using pen‐based actions. Sketched diagrams can be automatically ‘formalized’ into computer‐recognized and ‐drawn UML diagrams and then exported to a third party CASE tool for further extension and use. We describe the motivation for SUMLOW, illustrate the use of the tool to sketch various UML diagram types, describe its key architecture abstractions and implementation approaches, and report on two evaluations of the toolset. We hope that our experiences will be useful for others developing sketching‐based design tools or those looking to leverage pen‐based interfaces in software applications. Copyright © 2007 John Wiley & Sons, Ltd.     

OCL2Trigger: Deriving active mechanisms for relational databases using Model-Driven Architecture

Transforming integrity constraints into active rules or triggers for verifying database consistency produces a serious and complex problem related to real time behaviour that must be considered for any implementation. Our main contribution to this work is to provide a complete approach for deriving the active mechanisms for Relational Databases from the specification of the integrity constraints by using OCL. This approach is designed in accordance with the MDA approach which consists of transforming the specified OCL clauses into a class diagram into SQL:2003 standard triggers, then transforming the standard triggers into target DBMS triggers. We believe that developing triggers and plugging them into a given model is insufficient because the behaviour of such triggers is invisible to the developers, and therefore not controllable. For this reason, a DBMS trigger verification model is used in our approach, in order to ensure the termination of trigger execution. Our approach is implemented as an add-in tool in Rational Rose called OCL2Trigger.     

A case study in use of framework technology as the basis for a software engineering environment

In order to investigate the capabilities of varous types of integration infrastructure, the CASE Environments project at the Software Engineering Institute has conducted a series of studies integrating a variety of tools using framework technologies. This paper discusses one of these studies, in which a Software Engineering Environment was first modeled using a number of process notations and then constructed using control- and data-oriented frameworks. Public domain, commercial, and custom tools were integrated in support of the defined process scenario.     

Developing a CASE tool for distributed control applications

The function block (FB) concept has been adopted by recent International Electrotechnical Commission (IEC) standards to define a methodology for the development of modular, re-usable, open, and vendor-independent distributed control applications. Control engineers are already familiar with the FB construct, and field devices and fieldbuses are expected to be compliant with this approach in the near future. New generation FB-oriented CASE tools are required to support the whole development process. This paper presents an approach to the design and development of an IEC-compliant CASE tool (ICT). The proposed approach is based on a four-layer architecture that successfully unifies the FB concept with the Unified Modelling Language. During the development of our prototype ICT, this architecture proved to be very significant for the identification of the key abstractions that the ICT must provide as building blocks of its various diagrams used during the modelling process of control systems.     

构件复用的Web化支撑模型研究

本文基于一种以网络、Δgetn及领域为基础的Web化构件复用支撑模型,简述了其采用的框架模板表示方法及对构件化软件的分层规范:构造了领域框架、构件的分布式描述类库,提出以多Agent的手段实现分布式的构件搜索、管理,描述了各Agent的主要逻辑及相互协同关系.原型实现中使用了ASP、Java、JDBC、SQL等工具,并在实际开发中进行了应用试验.     

基于自组网的CAES的应用研究

一个Adhoc网络是一个多跳无线网络,网络中的节点互相通信而不依赖于预先架设的固定基础设施,本文介绍了自组网并讨论了其在教学中的应用。