基于CPL脚本语言的软交换应用服务器的研究

在软交换应用服务器的各种实现方案中；基于业务逻辑描述清晰，实现简单，以及同样在开放第三方业务支持上的便捷的考虑，本文提出了对基于CPL脚本语言的应用服务器的研究。用CPL脚本实现的应用可以达到业务逻辑可以和呼叫控制相分离的目的，为满足应用服务器频繁的业务逻辑修改以及丰富的新业务开发提供了最大便利，也为服务器的可靠性提供了很大的支持。     

复杂报表生成系统实现技术研究

摘要：软件应用开发中经常要进行既具有繁杂样式又包含复杂计算和统计的报表的制作。本文在总结应用开发经验基础上，提出了以模板驱动、解析器为中心的报表生成系统，建立了报表中大量数据计算的生成模型。根据报表特点，重点讨论了自定义XML标记系统、设计解析器进行标记解释、进而完成报表生成，体现了基于XML模板开发、关键功能组件化、整体架构和实现等技术。     

一种较少状态数的LR分析器

该文提出了一种新的LR分析器的构造方法,该方法从构造识别活前缀的确定有限状态自动机出发,通过合并有限状态自动机中可合并的等价状态对,对得到的有限状态自动机进行化简,从而得到较少状态数的LR分析表。该构造方法具有与LALR方法相同的语法识别能力并且避免了LALR方法在合并同心项目集时可能出现的归约一归约冲突。结果表明采用该方法构造文法分析表可以在一些情况下减少文法分析表的状态数目。     

数字音频AC-3比特流分析处理器的FPGA实现

通过对AC-3的标准比特流语法进行分析,设计了一种适用于AC-3的比特流分析处理器。该分析处理器从经过CRC校验的AC-3比特帧流中解帧格式化以分离出用于解码所需的比特流信息,然后分配一定的地址空间并将其送入音频缓冲寄存器组中以供后续电路的进一步处理。本文最后在FPGA上实现了AC-3比特流分析处理器的设计与仿真,仿真结果表明40 ns内即可完成一个标准的比特流帧的分析,能满足实时性要求。     

基于局部优先的汉语句法分析方法*

提出了一种利用局部优先信息对汉语分析算法进行优化的新方法,通过利用从语料库中自动获取的结构优先关系数据作为优先判断依据.此方法使目前的汉语概率分析器的整体效率提高了近30%,显示了很好的应用前景.     

An Operator Precedence Parser for Standard Prolog Text

Prolog is a language with a dynamic grammar which is the result of embedded operator declarations. The parsing of such a language cannot be done easily by means of standard tools. Most often, an existing parsing technique for a static grammar is adapted to deal with the dynamic constructs. This paper uses the syntax definition as defined by the ISO standard for the Prolog language. It starts with a brief discussion of the standard, highlighting some aspects that are important for the parser, such as the restrictions on the use of operators as imposed by the standard in order to make the parsing deterministic. Some possible problem areas are also indicated. As output is closely related to input in Prolog, both are treated in this paper. Some parsing techniques are compared and an operator precedence parser is chosen to be modified to deal with the dynamic operator declarations. The necessary modifications are discussed and an implementation in C is presented. Performance data are collected and compared with a public domain Prolog parser written in Prolog. It is the first efficient public domain parser for Standard Prolog that actually works and deals with all the details of the syntax.     

Token-by-token Syntax-directed Editing (Using an LR Parser)

This paper demonstrates a new approach to the building of a syntax-directed editor (SDE). The approach does not force the user to adopt a top-down syntax-oriented view of editing but supports the traditional text-editing approach of deciding which token to write next. Choices are made from menus listing only the tokens that are syntactically legal at a given point. The actual menus used by the editor are created by reference to the tables used by an LALR parser-generator.