第三部分论述了我国信息鸿沟的阶层，地区和个体差异特征。
The third part shows the diversity character of information-gap that exists widely between different are, stratum and individual.
土壤环境因子表征了石漠化在空间上岩性的差异特征，是石漠化类型的表现指标。
Factor of soil circumstance was an index of rocky desertification type and indicated the spatial difference of lithology.
目的了解山区农村中学教师自测健康在不同年龄层次上的差异特征，为促进学校心理健康教育提供理论依据。
Objective to investigate the differences of self testing health in different age levels, and to provide basis for health promoting school.
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