Support Environment for Active Software

新的信息系统功能更强、规模更大，但实施时间更短。通过三年的研究，我们得到了以下几个方面的基础：(1)设计适合于安全和适应需求变化的软件的算法我们不仅引入了预条件和后置条件，以确保安全运行符合规范，而且还引入了事前检查和事后检查，以提供不可预测的状态。设计和分析主动软件的语言及其语言处理器首先对软件的行为进行分析，并用状态转换图或π表达式表示结果。然后通过第一次翻译器得到具有活动功能的程序框架，手工添加每个函数的详细内容，第二次翻译器得到C或C++语言的程序文本。所获得的程序具有事件驱动激活的特点，并且易于更改。主动软件的可重构硬件结构主动软件的可重构硬件体系结构在主动软件中，主动软件的性能受每个主动函数的激活条件检测方法的影响。提出了一种新的事件驱动计算机体系结构，该体系结构具有可重构部件和处理器阵列，处理器之间的布线可改变，并对其设计结果进行了评估。在这些结果的基础上，我们计划通过3年的时间继续研究灵活、安全的软件、新的编程环境和适合它们的计算机体系结构。

New information system becomes higher in function and larger in size, but it requires shorter implementation time. For these trends, we aim to establish a new design method of large and safe software system and to develop appropriate environment for it.Through the research in 3 years, we gained one basis as follows.(1)Design algorithms suitable to safe and adaptive software for the change of requirementsWe introduced not only per-condition and post-condition to assure safe operation satisfying the specification, but also pre-check and post-check to provide for unpredictable states. They are formed with active functions attached each activation condition.(2)Language to design and analysis active software, and its language processorAt first we analyze the behavior of the software and express the result in state transition diagrams or π-expressions. Then we get the framework of the program with active functions by 1st-translator, append the detail contents of each function by hand, and gain the program text in C or C++ by 2nd-translator. The obtained program has the feature of event driven activation and is easy to change. The 2nd-translator is able to show the relation of calling and called functions, and also to make the program traceable the real calls at running time.(3)Re-configurable hardware architecture for active softwareOn active software the performance is affected by the method to detect events as activation condition of each active function. We proposed new architecture of event driven computer with re-configurable part and array of processors with changeable wire connection between processors, and evaluated the designed results of them.With these results through 3 years, we have some plans to continue the research about flexible and safe software, new programming environment, and suitable computer architecture for them.