Abstract: The dependence of the software on its environment mainly comes from the interaction. In the real application, sometimes, the interaction may not be successful. The interaction degree will have an effect on the ability of software. In order to test the property of software on the environment, it is necessary to compare the interaction ability of software with environment. In this paper, based on process algebra, the approximate measure model of software will be researched using complete trace semantics. The partial interaction will be formalized using the completed trace semantics. Some examples will be stated. The quantitative model which describes the approximate degree between software will be proposed. Some algebraic properties are proved. The criterion which evaluates the interaction ability with environment will be given.

Key words: partial interaction, measure, formalization, process algebra

摘要： 软件对环境的依赖性主要体现在软件与环境的交互。在实际中，有时软件与环境未必成功交互。其交互程度对软件的性能有着很大的影响。为测试不同软件在环境下的性能，需要对软件与环境的交互能力进行比较。在进程代数理论基础上，利用完整迹语义，建立软件近似程度的量化模型。形式化描述软件与环境的部分交互。列举一些例子对模型进行说明。建立软件近似程度的量化模型，证明一些代数性质。进一步，建立评价软件在与环境交互方面好坏的标准。

关键词: 部分交互, 度量, 形式化, 进程代数