The NDB database specified in the RAISE specification language

This paper answers a challenge designed to test the modularization features of specification languages. The RAISE Specification Language (RSL) is shown to have the power necessary to meet the challenge.Basic features of RSL, particularly those useful for the problem, are introduced. Two solutions to the problem are exhibited. The first follows the structure of the challenge problem very closely and is model-based in style. The second shows how RSL may be written in an algebraic style.An example of a proof of implementation is also given.     

结合UML和RAISE的软件开发方法研究

面向对象方法形象、直观、使用方便,但难以消除二义性。形式化方法严密、可靠、可验证,但软件规约不直观,不符合开发人员的使用习惯,探讨一种结合面向对象方法UML和形式化方法RAISE的软件开发方法。     

Specification,proof, and model checking of the Mondex electronic purse using RAISE

This paper describes how the communication protocol of Mondex electronic purses can be specified and verified against desired security properties. The specification is developed by stepwise refinement using the RAISE formal specification language, RSL, and the proofs are made by translation to PVS and SAL. The work is part of a year-long project contributing to the international grand challenge in verified software engineering. J. C. P. Woodcock     

Experience on knowledge-based software engineering: A logic-based requirements language and its industrial applications

A formal requirements specification language plays an important role in software development. Not only can such language be used for stating requirements specification, but also can be used in many phases of software development life cycle. The FRORL project started from constructing a language with a solid logical foundation and further expanded to research in verification, validation, requirements analysis, debugging, and transformation. Research in this project aided in some industrial applications in which a code generation tool produced software for embedded systems. This article reports the experiences gained from this project and states the value of research in knowledge-based software engineering.     

Requirements for tools for ambiguity identification and measurement in natural language requirements specifications

This paper proposes a two-step approach to identifying ambiguities in natural language (NL) requirements specifications (RSs). In the first step, a tool would apply a set of ambiguity measures to a RS in order to identify potentially ambiguous sentences in the RS. In the second step, another tool would show what specifically is potentially ambiguous about each potentially ambiguous sentence. The final decision of ambiguity remains with the human users of the tools. The paper describes several requirements-identification experiments with several small NL RSs using four prototypes of the first tool based on linguistic instruments and resources of different complexity and a manual mock-up of the second tool.

Formalizing non-interference for a simple bytecode language in Coq

In this paper, we describe the application of the interactive theorem prover Coq to the security analysis of bytecode as used in Java. We provide a generic specification and proof of non-interference for bytecode languages using the Coq module system. We illustrate the use of this formalization by applying it to a small subset of Java bytecode. The emphasis of the paper is on modularity of a language formalization and its analysis in a machine proof. C. B. Jones     

UML状态机模型元素的RSL形式化定义

UML状态机作为UML动态描述机制的重要组成部分,在描述系统及模型的动态行为时扮演着重要的角色,但已有的UML动态语义缺乏准确的形式化描述。首先将UML状态机抽象成图;再将图通过传统的有穷自动机进行语义扩展,同时增加状态分层,形成一个基于UML状态机的有穷自动机;然后用RAISE规约语言RSL对扩展后的自动机进行形式化定义,使UML状态机中的模型元素的语义更加清晰、精确,为后期的UML状态机的操作语义形式化研究打下基础。     

A unified formal basis for the CASE tools system

XYZ system is a CASE tools system based on a temporal logic language XYZ/E which can represent every essential feature of conventional HLL's (sequential or concurrent), specifications of different levels, production rules, operational semantics of graphic languages in a uniform framework. With this formal language as the common basis, all the CASE tools including various kinds of graphic tools for distributed process, concurrent programs with phased memory and sequential programs, tools for verification, rapid-prototyping, language transformation, and module management can be connected freely to form more sophisticated and integrated systems.     

A survey of tools for the validation and verification of knowledge-based systems: 1985-1995

This paper presents the findings of a survey of software tools built to assist in the verification and validation of knowledge-based systems. The tools were identified from literature sources from the period 1985-1995. The tool builders were contacted and asked to complete and return a survey that identified which testing and analysis techniques were utilised and covered by their tool. From these survey results it is possible to identify trends in tool development, technique coverage and areas for future research.     

FDT与FDT工具及其研究

叙述形式化方法的基本概念，研讨了国际上标准的以及目前使用的应用于描述顺序软件、并发软件和基于图形的形式化描述，同时论述了支持形式化描述技术的工具的任务、作用和分类。     

An abstract programming language and correctness proofs

The realization of an abstract programming language is a good approach for automating the software production process and facilitating the correctness proof of a software system.

This paper introduces a formal language for programming at the abstract level by combining Pascal with VDM (Vienna Development Method). The notation provided by the language obliges programmers to consider the correctness of programs throughout the whole process of programming, and the proof axiom and rules presented in this paper may be used to prove the correctness of programs. A complete example is given to illustrate how to program using APL and how to prove the correctness of programs using the given axiom and rules.     

Applying abstraction and formal specification in numerical software design

Numerical software development tends to struggle with an increasing complexity. This is, on the one hand, due to the integration of numerical models, and on the other hand, due to change of hardware. Parallel computers seem to fulfill the need for more and more computer resources, but they are more complex to program.

The article shows how abstraction is used to combat complexity. It motivates that separating a specification, “what,” its realisation, “how,” and its implementation, “when, where,” is of vital importance in software development. The main point is that development steps and levels of abstraction are identified, such that the obtained software has a clear and natural structure.

Development steps can be cast into a formal, i.e., mathematical framework, which leads to rigourous software development. This way of development leads to accurate and unambiguous recording of development steps, which simplifies maintenance, extension and porting of software. Portability is especially important in the field of parallel computing where no universal parallel computer model exists.     

C语言程序设计教学方法的现实探微

随着我国经济的快速发展,我国教育事业在发展过程中面临着新的挑战。C语言程序设计课程,是我国计算机课程中一个重要的组成部分,具有广泛的适用性与实践性;C语言程序设计课程教学效率与质量的提升,能够一定程度上促进我国计算机课程的总体发展,有效地培养学生对于计算机问题的分析与解决能力,提高学生的实践技能,科学合理的C语言程序设计教学方法,是确保教学效率与质量提升的关键,C语言程序设计课程教师应当充分重视教学方法的运用,根据实际情况选择与更变教学方法。     

局域网管理软件测试工具研究

分析了局域网软件测试工具的普遍方法,针对目前缺乏的局域网环境模拟类测试工具的现状,给出了对网络端点IP/MAC、TCP/IP协议栈和网络服务三层进行模拟的设计方案。     

项目教学法在计算机公共基础课教学中的应用

新世界以来随着科技水平的不断发展,计算机技术正逐渐融入我们生活的方方面面,计算机已成为每一名新时代青年所必须掌握的技能.因此在青少年的教育培养中,如何激发其对计算机学习的兴趣,增强其计算机理论知识与实际操作水平的不断提升,从而促进学生综合素养的全面提升,为其今后更好的融入残酷的社会竞争打下良好的基础.本文笔者结合自身经验对项目教学法展开的主要原则进行了总结,并对如何更好的开展项目教学法在计算机公共基础课上的应用做出了探究与分析,希望对广大同行有所借鉴.     

浅谈计算机软件开发技术的应用研究与趋势

计算机软件是计算机的重要组成部分,计算机软件的开发直接影响着计算机的发展。本文主要就计算机软件开发技术的现状、计算机软件开发技术的面临的问题、技术开发的方式、软件开发的应用、软件开发技术的趋势进行了研究,为以后计算机开发技术的应用研究提供一些理论基础。     

Theories, tools and research methods in program comprehension: past, present and future

Program comprehension research can be characterized by both the theories that provide rich explanations about how programmers understand software, as well as the tools that are used to assist in comprehension tasks. In this paper, I review some of the key cognitive theories of program comprehension that have emerged over the past thirty years. Using these theories as a canvas, I then explore how tools that are commonly used today have evolved to support program comprehension. Specifically, I discuss how the theories and tools are related and reflect on the research methods that were used to construct the theories and evaluate the tools. The reviewed theories and tools are distinguished according to human characteristics, program characteristics, and the context for the various comprehension tasks. Finally, I predict how these characteristics will change in the future and speculate on how a number of important research directions could lead to improvements in program comprehension tool development and research methods. Dr. Margaret-Anne Storey is an associate professor of computer science at the University of Victoria, a Visiting Scientist at the IBM Centre for Advanced Studies in Toronto and a Canada Research Chair in Human Computer Interaction for Software Engineering. Her research passion is to understand how technology can help people explore, understand and share complex information and knowledge. She applies and evaluates techniques from knowledge engineering and visual interface design to applications such as reverse engineering of legacy software, medical ontology development, digital image management and learning in web-based environments. She is also an educator and enjoys the challenges of teaching programming to novice programmers.     

软件项目中需求管理的探索与实践

软件需求在软件产品的整个生命周期中占有十分重要的位置,对后续的软件开发和维护的成败具有决定性意义。在实践中,需求管理却往往得不到足够的重视。从软件需求和需求工程的概念入手,分析了软件需求管理中存在的内部与外部问题,并着重介绍了需求开发和管理的有效方法,提出了简单可行的需求分析评价标准。     

Evaluating learning, design, and engagement in web-based learning tools (WBLTs): The WBLT Evaluation Scale

Web-based learning tools (WBLTs), also known as learning objects, are online, interactive tools that support the learning of specific concepts by enhancing, amplifying, and/or guiding the cognitive processes of learners. Research examining the effectiveness of WBLTs is somewhat limited because sound, reliable, valid evaluation metrics are sparse, particularly in the K-12 environment. The purpose of the following study was to re-examine the Learning Object Evaluation Scale for students (LOES-S), originally developed by Kay and Knaack (2009), to assess three key constructs: learning, design, and engagement. Over 800 middle and secondary schools students participated in high quality, pre-designed lessons intended to accentuate the use of WBLTs. Data collected from the new WBLT Evaluation Scale demonstrated good internal reliability, construct validity, convergent validity and predictive validity.