a progressive line simplification algorithm
guo qingsheng christoph brandenberger lorenz hurniprofessor; ph.d supervisor; school of resource and environment science; wuhan university; 129 luoyu road; wuhan 430079; china.
..............page:41-45,75
gis conceptual data model
xiao lebin zhong ershun liu jiyuan song guanfuassociate researcher; institute of geographic sciences and natural resources; chinese academy of sciences; 3 datun road; anwai; beijing 100101; china.
..............page:19-25