基于Web的油菜生产专家系统施肥知识表示

油菜施肥决策是油菜生产中的关键栽培管理技术之一，因而成为油菜专家系统的重要组成部分。配方施肥采用精量或半精量的先进科学施肥替代耕种者个人的经验施肥，在减少环境污染和提高肥料效益等方面意义重大。由于配方施肥涉及描述性知识、关联性知识和计算性知识，因此在专家系统的知识表达中具有一定的综合性与复杂性，在分析油菜需肥特性的基础上，提出了专家系统施肥决策应考虑的主要因素，阐述了油菜配方施肥技术，论述了Web油菜生产专家系统配方施肥知识表示、算法和知识规则，该配方施肥知识表示在作物专家系统中具有一定的通用性。

Knowledge Representation of Prescribed Fertilization in Web-Based Expert System of Rapeseed(B.napus) Production

Fertilization decision is one of the key cultivation techniques in rapeseed ( B.napus ) production, and thus becomes the important part of rapeseed expert system. Prescribed fertilization,in which precision or half-precision fertilization takes the place of the experience of farmers,has magnitude meanings in reducing environment pollution and increasing fertilizer benefit. The knowledge representation of prescribed fertilization in expert system is of integration and complexity,as prescribed fertilization knowledge involved the describing, relating and computing knowledge. Based on the analysis of rapeseed demands characteristics of fertilizer,this paper is an attempt to put forward the main factors that expert system fertilization decision should consider,to discusse the rapeseed prescribed fertilization technology, and at last,to bring forward the knowledge representation, algorithm and rules of prescribed fertilization in web-based expert system of rapeseed production. The knowledge representation is general in crop expert system,as pointed out in the paper.