面向对象类谓词逻辑知识表达模式及其在选线系统中的应用

将谓词逻辑知识表达法与面向对象技术相结合,提出面向对象的类谓词逻辑知识表达模型。该模型用对象和信息表现问题中的事物及其关系;用类和继承来模拟人们的思维方式。模型中通过采用"测验分数"语义,有效地解决了不确定性知识的表达问题;用类代替关系定义域中的实体,可通过缩小搜索空间而提高推理效率。以选线系统中的设计状态知识,说明类谓词逻辑知识表达模式在选线领域知识表达中的应用。

A Class-predicate Logic Knowledge Expression Model and Its Application to Railway Alignment System

The knowledge representation technology is a key for intelligent environment modeling in the virtual environment railway alignment system. The paper presented a class-predicate logic knowledge representation model which integrates two popular knowledge representation techniques (object-oriented representation and traditional predicate logic knowledge expression). It representes things and their relation with objects and messenge, imitates the thinking of a man with class and inheritance. In class-predicate logic model, the uncertain domain-specific knowledge of railway alignment can be dealt with by using 'test-fraction' efficiently. Replacing the entity with class in the value range, the search space of knowledge can be reduced and the inference efficiency improved. On the other hand, by using the class-predicated inference method with limited value, the inference and relativity check become more efficient than the traditional logic predicated one. The paper cites one example of procedure knowledge which provides the application of class-predicate logic knowledge representation. The class-predicate logic knowledge representation model is proved to be an efficient method for knowledge representation for railway alignment system.