轻量级脚本引擎的设计与实现

通过嵌入脚本引擎为应用程序提供脚本支持是实现应用程序可定制和可扩展的有效方法,但现存的脚本语言难于掌握,引擎庞大使应用程序的效率降低。为了解决该问题,设计了语法简单易学的脚本语言Vblet,实现了Vblet的轻量级脚本引擎。该引擎支持脚本无缝地使用应用程序实现的类和函数,并具有很好的性能。     

脚本语言发展研究

一、引言在过去30年里,编程人员在编写程序的过程中更多注重的是如何使用高级程序设计语言编写出具有个性的应用程序,但这一观念目前正逐步发生了根本性的变化。这种变化表现为由高级程序设计语言(例如C或C~( ))向脚本语言(例如Perl或TcL)的过渡。因此,比较脚本语言和高级程序设计语言的各自特点有利于我们了解这种变化的必然性。     

仿真环境中智能化控制语言的研究

智能化控制语言可控制仿真系统中的实体,使其表现出智能化行为。本文定义了一种智能化控制脚本语言ICSL(Intelligent Control Scripting Language),并实现了ICSL的解释器。ICSL支持基本的控制语句和核心对象,针对领域特征,对仿真领域的语义进行编码,并提供语义扩展机制,为控制策略的制定者提供一种灵活表达策略的手段。ICSL语言的解释器将智能化策略映射为仿真系统中实体的行为序列,实现了对仿真实体的智能化控制。最后,本文通过把ICSL语言用于战场仿真系统对其实用性进行了系统的实验研究,结果表明,基于ICSL语言定义的控制策略可以有效地映射到仿真系统中,从而完成对仿真实体的智能化控制。     

高性能计算环境下陆面建模系统的关键技术

为了从多角度精确评估陆面特征,改善陆面过程模型的模拟性能,并为研究者提供一套完整的从数据处理到模拟分析的陆面建模系统.采用多种脚本语言和模型数据融合方法来构建陆面建模系统.此建模系统集成观测数据、陆面过程模型、高性能计算、数据处理和分析方法,以及可视化等技术手段.在此系统内针对两种不同的陆面过程模型进行了应用示范,证明了不同脚本语言的建模系统在目前高性能计算环境中的应用潜力,以及不同可视化方案在陆面建模系统的作用.     

Verifying data refinements using a model checker

In this paper, we consider how refinements between state-based specifications (e.g., written in Z) can be checked by use of a model checker. Specifically, we are interested in the verification of downward and upward simulations which are the standard approach to verifying refinements in state-based notations. We show how downward and upward simulations can be checked using existing temporal logic model checkers.In particular, we show how the branching time temporal logic CTL can be used to encode the standard simulation conditions. We do this for both a blocking, or guarded, interpretation of operations (often used when specifying reactive systems) as well as the more common non-blocking interpretation of operations used in many state-based specification languages (for modelling sequential systems). The approach is general enough to use with any state-based specification language, and we illustrate how refinements between Z specifications can be checked using the SAL CTL model checker using a small example.     

Development of a simulation framework and applications to new production processes in shipyards

Recently, a floating crane is frequently used for the block lifting, transportation, turn-over, and assembly processes in waves. For these production processes, it is important to detect collision in advance between assembly blocks or the block and the other facilities like the wire rope and the barge which are carrying the block. The tension of the wire rope also needs to be calculated to check that the maximum value is less than the safety criteria. In this paper, a mathematical model is constructed based on multibody system dynamics considering the external forces such as the hydrostatic, hydrodynamic, wind force, etc. To observe the dynamic motions of the floating crane and the block, and to calculate the tension of the wire rope, the time and event simulations are performed by solving the mathematical model in the computer. For applying the simulations to the various production processes in shipyards, a simulation framework is developed. The simulation framework consists of a simulation kernel, application-specific modules, a simulation coordinator, development tools, and post-processing tools. The simulation kernel manages both DEVS (discrete event system specification) and DTSS (discrete time system specification) to deal with various simulation requests. The application-specific modules provide the functions used in application systems, such as dynamic analysis, collision detection, visualization, wire rope force calculation, hydrostatic force calculation and hydrodynamic force calculation. The simulation coordinator manages the data of the simulation kernel and the application-specific modules. The development tools provide a development process, a scenario manager, and a simulation model generator. The post-processing tools are used to report the simulation results. The examples of block lifting, transportation, turn-over, and assembly simulations are developed based on the framework to show that the framework is useful for the simulations of the production processes using one or more floating cranes.     

基于Web开发的几种服务器端脚本语言的分析与比较

基于Web服务器脚本语言的基本特点及研究现状,对目前发展较成熟的ASP,JSP,PHP和Cold Fusion等服务器端脚本语言进行了详细比较,并深入分析了Cold Fusion脚本语言的Web开发,旨在探寻脚本语言在Web开发方面的应用及其发展方向,为研究者提供有益帮助。     

Mechanised support for sound refinement tactics

ArcAngel is a tactic language devised to facilitate and automate program developments using Morgan’s refinement calculus. It is especially well suited for the specification of high-level refinement strategies, and equipped with a formal semantics that additionally permits reasoning about tactics. In this paper, we present an implementation of ArcAngel for the ProofPower theorem prover. We discuss the underlying design, explain how it implements the semantics of ArcAngel, and examine the interplay between ArcAngel tactics and the native reasoning support of the prover. We also discuss several extensions of ArcAngel that have been entailed by our implementation effort. They are of practical importance and provide a unification of the related tactic languages Angel and ArcAngel C. Our main result is a mechanisation that reflects directly the ArcAngel semantics, and can be used with any programming model for refinement. The approach can be used to support other formal tactic languages using other theorem provers.