Supporting control definition in programming languages

The paper is devoted to illustrate a new approach to control definition in programming languages. The DIL system developed by the authors to allow a user to define and utilize his own control mechanisms in program design and construction is presented. The motivations of the proposal are discussed in the frame of software engineering and abstraction programming. The main features of DIL are introduced in an informal way through a number of examples of increasing complexity. The basic mode of operation of the system is described and an architecture for the implementation of DIL is given. Meaningful sample applications are shown to validate the main features of the language. Promising directions for future research are presented as well. A run-time model of DIL is sketched in the Appendix.     

IFS与L系统的统一描述语言及其分类

为了更高效地表示分形图形,依据形式语言的文法结构及正则表达式的文法规则,通过引入代数运算,提出了一个能够对L系统和迭代函数系统(IFS)统一描述的语言代数系统。根据语言代数系统产生式的文法规则,将此系统的产生式集划分为五类。结合分形理论,此语言代数系统着重将DOL系统、迭代函数系统(IFS)、带凝聚集迭代函数系统(凝聚IFS)、随机迭代函数系统(IFSP)和再归迭代函数系统(RIFS)等进行描述,同时用此系统的正则表达式方程解将分形吸引子进行代数表示,并给出一些实例。通过实例表明,分形图形可以用该语言代数系统简单、明了、高效地表示。     

智能数据库工具技术

本文详细介绍了一个智能数据库支持工具FoxPert的设计与实现技术.该工具立足于主流数据库系统，采用一种增强的松耦合结构实现了FoxPro,Oracle与知识表示语言CLIPS(C language integrated production system)的无缝连接.它在体系结构、集成平台、集成方向和集成形式上具有鲜明的技术特点，已在不同部门推广应用.     

A Methodology And Tool Set For Supporting The Development Of Graphical User Interfaces

A methodology and tool set for building application (assumed to be inherently non-graphical) software with graphical user interface is described. Initially, pure application software is built from a set of basic building blocks; subsequently, graphical representations for application objects are defined without direct coding and then the graphical user interface is generated automatically. This paper concentrates on the graphical representation aspects of the user interface. Portability, configurability and sound software engineering principles are major considerations in the design of the overall system architecture. The prototype implementation is based on VDM (Vienna Development Method), Object-based Design, GKS (Graphical Kernel System) and the programming language ADA. An example from CIM (Computer Integrated Manufacturing) is used to illustrate the methodology presented here.     

Description of a menu creation and interpretation system

The Menu Creation and Interpretation System (MCIS) is a menu system development tool that can provide the high-level control structure and the user interface for any application program or software system. MCIS simplifies the task of building menu-driven systems while presenting a user interface that is easily learned and easy to use. Human factors considerations have been stressed in the system design. A user is able to jump from one menu to another, obtain help whenever it is needed, and easily recover from errors. Menu systems created with MCIS are extensible and easily modified, enabling them to meet changing user needs. In addition, through the specification of user profiles, menu systems can be customized to meet the needs of individual users. MCIS is written in the C programming language under the UNIX

1 Unix is a trademark of Bell Laboratories.

operating system. It can be used in any environment that includes a C compiler and the UNIX standard I/O library.     

An Environment for Rapid Prototyping of Interactive Systems

This paper shows an environment which supports the development of multi-thread dialogue interactive systems.The environment includes several tools and run-time support programs for the design and implementation of the user interface of an interactive system.First,methods of user interface specification with Elementary Nets are discussed.Then,the syntax of a user interface specification language based on Elementary Nets and the pre-compiler for the language as well as a graphic editor for Elementary Nets construction are described.Finally,an example is given to illustrate the design process of a user interface.     

A dialogue system for creating and manipulating graphical symbols and structures

Conventional higher level programming languages have not been designed for effective application to the kind of problems which arise in interactive computer graphics. In order to correct this, efforts have been made to use conversational languages or to design command languages which allow the user to interact with the system via light buttons or teletype.This paper describes a conversational system — called DIGS — using a keyboard-oriented language. The language enables the user to construct models step-by-step with a minimum of typing effort. Intermediate results (graphic or non-graphic) may be controlled at each point of the construction process.The purpose is to provide a tool for easily creating and editing fairly complex symbols as well as hierarchic pictures. Data can be associated with the picture parts and relationships defined between them.     

基于MATLAB的分形仿真研究

研究重点是用MATLAB编程语言来实现分形图形。如应用分形几何学中的IFS系统理论和L系统理论,用MATLAB语言生成具有自相似特征的、精美的分形图案。为地貌描述、生物学的仿真研究、艺术设计等领域提供了新的方法。     

The systems programming language,Malus

This paper reports on the design and development of a high level language, Malus, for use in implementing a time-sharing system. Emphasized are the ways that the language and its compiler accommodate the specialized requirements of systems programming and programmers. Among these are the need to generate highly efficient object code, to allow inter-programmer communication by program self-documentation, and to define and organize system tables and data. In addition, the Malus compiler is highly modular; thus the language may be modified or augmented in response to user needs unforeseen during langauge design. Systems programs cannot be machine independent and Malus allows explicit control of emitted code when an application requires particular efficiency or use of privileged instructions. There is also a facility allowing nested redefinition of identifiers. Efficient storage management and data access is effected by the availability of based structures, a register storage class and built-in functions to facilitate their use. Malus is evaluated both in terms of some general criteria for systems implementation languages and by an appraisal of user reactions. While this assessment shows a few areas where the language might be improved, it is felt that Malus is a valuable and effective tool for systems implementation.     

Integrating discrete controller synthesis into a reactive programming language compiler

We define a mixed imperative/declarative programming language: declarative contracts are enforced upon imperatively described behaviors. This paper describes the semantics of the language, making use of the notion of Discrete Controller Synthesis (DCS). We target the application domain of adaptive and reconfigurable systems: our language can serve programming closed-loop adaptation controllers, enabling flexible execution of functionalities w.r.t. changing resource and environment conditions. DCS is integrated into a1 programming language compiler, which facilitates its use by users and programmers, performing executable code generation. The tool is concretely built upon the basis of a reactive programming language compiler, where the nodes describe behaviors that can be modeled in terms of transition systems. Our compiler integrates this with a DCS tool, making it a new environment for formal methods. We define the trace semantics of our contracts language, describe its compilation and establish its correctness, and discuss implementation and examples.     

基于AltaRica的故障自动化建模和分析

随着系统规模和复杂性的增加,系统安全性建模和分析技术在关键安全系统中得到了广泛应用.AltaRica是用于安全性分析的高级建模语言,AltaRica模型能够更好地反映系统功能和逻辑结构,消除传统安全性分析手段与系统设计的隔阂,提高安全性模型的可维护性和重用性.文章将AltaRica与计算机可视化建模技术相结合,开发了支...     

Computer physics communications instructions to authors (fourth revision)

External Standard Data Structures and I/O interface service functions will be described as a programming tool to pass data between different programs. The objective for the design of external standard data structures has been to guarantee a maximum mutual independence of the individual programs. The objective for the design of the I/O interface has been to guarantee a maximum independence of the user programs from the system I/O functions. The external data structures and I/O service functions described have been in use for many years in the MUNICH Molecular Program System. They have been found flexible, open-ended, and easy and convenient to use and to implement in a higher-level programming language.     

COMPLEX: an object-oriented logic programming system

The design and a prototypical implementation of COMPLEX, which is a logic-based system extended with concepts from the object-oriented paradigm and is intended as a tool for the development of knowledge-based applications, are described. The system supports a logic language, called Complex-Datalog (C-Datalog), enhanced by semantic constructs to provide facility for data abstraction. Its implementation is based on a bottom-up computational model that guarantees a fully declarative style of programming. However, the user is also given the possibility of running a query using a top-down model of computation. Efficiency of execution is the result of the integration of different novel technologies for the compilation and the execution of queries     

SDN数据平面软件一致性测试用例生成方法

SDN （Software-Defined Networks）发展的目的在于解决架构复杂且分散的传统网络出现的问题,使网络具有更强的灵活性.P4编程语言的特征在于用户可以直接根据自己对处理数据包的需求定义P4程序,然后经过编译通过适配文件将用户需求配置到网络设备.面向P4编程语言的SDN数据平面一致性测试本质上是将面向P4程序的一致性测试用例发送给P4网络设备,其目的在于获取实际输出和预期输出的一致程度.一致性测试用例是执行一致性测试的载体,而传统的人工构造测试用例是一项繁琐耗时费力的工作.本文重点分析了面向P4编程语言的SDN数据平面软件一致性测试用例设计原则和一致性测试用例生成方法,给出了一致性测试用例覆盖标准,设计了命令信息实体结构和测试用例实体结构,以装载P4程序的simple_switch虚拟交换机为测试对象说明一致性测试用例生成过程,实现了一个用于P4网络设备一致性测试的测试用例自动生成工具并验证了该工具自动生成测试用例的有效性,实现了一致性测试用例构造过程简易性.     

Object management in a programming-by-example,parametric, computer-aided-design system

We present the handling of graphical objects in a programming-by-example, CAD system. The object-naming mechanism described here supports the automatic generation of parameter-independent object references in parametric programs. These programs are produced via user interaction during the construction of parametric objects. We use standard programming language control structures and modularity for the parametrisation of variants, repetitive similarities and flexible hierarchical object structure. The object management of parametric entities with varying topology ensures the correctness of their instantiating parametric programs for large domains of parameter values.     

VB和Matlab混合编程方法——MatrixVB

Matlab是目前应用最广泛的数值科学计算语言,同时也是系统分析和仿真的强大工具,VB是目前使用最广泛的可视化编程工具。MatrixVB作为一种数学工具有效地将Matlab的强大功能融入到了Visual Basic中。通过一个具体的例子演示了如何在Visual Basic6．0中使用MatrixVB函数。结果显示,将Matlab的强大的计算功能与VB在图形用户开发方面的优势结合起来,有效地解决了复杂的雷诺方程的求解问题。