一个面向语义的解释器自动生成技术

本文给出从指称语义自动生成解释器后端的一种技术.解释器被表示成PASCAL_like形式.     

工业机器人解释器语义分析研究

介绍了语义分析的发展现状。针对目前解释器语义分析效率较低的问题,并结合工业机器人控制系统的特点,研究了利用语法分析栈来实现工业机器人解释器语义分析的方法,并实现了工业机器人编程语言IRL的语义分析。基于该方法的解释器在Visual Studio2005平台上用C＋＋实现,生成的目标代码运行于WinCE嵌入式系统。实验结果证明了该方法的正确性和高效性。     

基于规则的统计数据审核系统

文章针对统计数据审核要求，提出了一种基于规则的统计数据审核解决方法。介绍了统计审核规则的分类和表示方法，并给出了构造审核规则解释器的方案。     

适用于无线体域网的动态口令认证协议

无线体域网中传输的是与生命高度相关的敏感数据，身份认证是信息安全保护的第一道防线。现有的基于人体生物信息的身份认证方案存在信息难提取、偶然性大和误差性大的问题，基于传统密码学的认证方案需较大计算资源和能量消耗，并不适用于无线体域网环境。为此，在动态口令和非对称加密机制基础上，提出一种适用于无线体域网的动态口令双向认证轻量协议，并对其进行形式化分析。通过理论证明、SVO逻辑推理及SPIN模型检测得出：该协议满足双向认证，且能够抵御重放攻击、伪装攻击、拒绝服务器攻击和口令离线攻击，具有较高安全性。     

Throw-away compiling

A method of compiling called ‘throw-away compiling’ is presented. This combines the merits of compilation and interpretation. If enough storage is available for a program, it can be compiled in the normal way; if not, the program is stored in a concise intermediate form and compiled dynamically at run-time, making use of whatever storage is available. When this storage runs out, the previously compiled code is thrown away and the storage is re-used. The technique is specially suitable for small machines, especially those without virtual memory. The paper explains the advantages and disadvantages of throw-away compiling, and describes a project where a throw-away compiler was implemented and tested for performance.     

Java智能卡内存调度机制研究与分析

以提高JCVM解释器的执行效率为出发点,以减少解释器工作时对外部存储器的访问次数为目标,提出一种基于双缓冲区的内存调度机制,并给出算法实现的关键片段。分析这种机制存在的不足;与传统方式相比,减少了对内存的访问次数,提高了指令解释执行的连续性程度,提高了解释器执行的效率,简化了系统结构设计的复杂性。     

基于STEP-NC标准的数控技术发展现状及趋势

分析ISO6983目前存在的缺点,通过对ISO6983与STEP-NC标准的比较,引出STEP-NC的概念,并简述STEP-NC的数据模型。主要对STEP-NC研究现状的几个方面进行了较为详细的分析:对于STEP-NC数控程序的生成,并给出生成流程图;对STEP-NC文件进行解释,即STEP-NC解释器极其功能;对STEP-NC控制器的研究状况及内容;以及基于STEP-NC标准的NURBS曲面插补等。最后总结了STEP-NC数控加工方式具有优异的开放性、智能性、网络化特征,基于STEP-NC标准的数控系统必将成为开放式数控系统的主要发展趋势,对于提高我国数控水平乃至全面提高自动化制造水平具有重要意义。     

A highly-structured interpreter for a SNOBOL4 subset

A highly-structured and conceptually simple processor, written in Algol 68, for a basic but useful subset of SNOBOL4 is presented. It provides a significant, large-scale demonstration of a particular methodology for constructing ‘master’, machine-independent implementations of programming languages. The processor is closely related to a formal operational definition of the SNOBOL4 subset in that it incorporates an abstract machine, a high-level abstract syntax (in the form of mutually recursive mode definitions) for the internal form of programs, and a set of mutually recursive interpretation procedures for programs in this internal form. The various aspects of the processor are documented in some detail. The experience of testing the processor is briefly discussed.     

Design and coding considerations of the soil data language interpreter

A query language, named Soil Data Language (SDL), for retrieving information from a Soil. Data Bank, is part of the ARSIS (A Relational Soil Information System) system, currently being developed in Greece. The interpreter of the language accepts input programs, expressed as SDL commands, and outputs the requested information. This paper describes design principles employed during the coding of the interpreter of the language. The derived program can be modified to cover eventual alterations to the specifications of language or the content and structure of the data bank. The study may be seen as an initiative to the design of Generalized Soil and Land Information Systems that primarily are concerned with the easy adaptation to a variety of National processing requirements.     

Interpretation and code generation based on intermediate languages

The possibility of supporting high level languages through intermediate languages to be used for direct interpretation and as intermediate forms in compilers is investigated. An accomplished project in the construction of an interpreter and a code generator using one common intermediate form is evaluated. The subject is analysed in general, and a proposal for an improved design scheme is given.