In order to make cst more practical and easier to popularize , it is essential and urgent to keep on studying and developing cst at lower unit level to establish basic soil classification units of cst 发生分类到系统分类的参比关系复杂,参比难度大,原因在于它们的分类体系和划分标准是完全不同的。
1 . 4 based on the attribute db , the soil classification graphic db is set up by using arc / info cis . the soil order , suborder sketchs and basic classification unit ( series ) sample maps , make the distribution of soil in hubei province clear at a glance 4在属性数据库的基础上,利用arc infogis建立了湖北省土壤分类图形数据库(空间数据库) ,运用计算机编制和输出了全省土壤系统分类土纲、亚纲概图和基层分类单元(土系)样块图,使全省土壤分布状况一目了然。
Primarily there are two aspects : 1 ) the calculation model of the value of land classifying units - - model of time distance attenuation . in the calculation model of the value of land classifying units , author brings forward the model of time distance attenuation . in this model adopting the network analysis , and by establishing the road network , and proceeding path analysis , computing the time distance , then proceed the exponential attenuation or straight line attenuation on time distance , get the value of influence factor of the land classification unit 主要有两个方面: 1 、定级单元分值计算模型? ?时间距离衰减模型在定级单元分值的求取模块中,提出了时间距离衰减模型,模型中采用网络分析的方法,通过建立道路网络,进行路径分析,求取时间距离,进而按时间距离进行指数衰减或直线衰减,得到定级单元因素因子影响分值。