草图信息的存储与传输是草图系统在信息共享乃至网络协同方面需要解决的问题,其核心在于草图信息的一致表示。本文从信息表示和信息传榆两个维度,建立了草图信息表示模型框架。该框架采用域模型思想,包括域属性、逻辑模型、转换模型、...草图信息的存储与传输是草图系统在信息共享乃至网络协同方面需要解决的问题,其核心在于草图信息的一致表示。本文从信息表示和信息传榆两个维度,建立了草图信息表示模型框架。该框架采用域模型思想,包括域属性、逻辑模型、转换模型、对象模型和控制模型,它们实现了草图信息的一致表示、统一管理和信息存储、传输。最后,从静态和动态两方面,对草图信息的建模过程进行了详细描述,给出了草图信息表示的 XML 实现策略,并对信息传输技术进行了分析。展开更多
By taking Daan city in Jilin Province as a research object and by using TM image in 1989 and ETM + image in 2001 from American LANDSAT satellite,all kinds of maps and documentation,information of grassland,saline-alka...By taking Daan city in Jilin Province as a research object and by using TM image in 1989 and ETM + image in 2001 from American LANDSAT satellite,all kinds of maps and documentation,information of grassland,saline-alkalized land,cropland,water area and forestland is extracted by man-computer interactive interpretation method with ArcView and ArcInfo GIS software, and statistics data is acquired. On the basis of this the changing trend of land use types in the next ten years is forecasted and analyzed with Markov model. The results indicate that the problem of grassland degradation in the study area is quite serious.展开更多
文摘草图信息的存储与传输是草图系统在信息共享乃至网络协同方面需要解决的问题,其核心在于草图信息的一致表示。本文从信息表示和信息传榆两个维度,建立了草图信息表示模型框架。该框架采用域模型思想,包括域属性、逻辑模型、转换模型、对象模型和控制模型,它们实现了草图信息的一致表示、统一管理和信息存储、传输。最后,从静态和动态两方面,对草图信息的建模过程进行了详细描述,给出了草图信息表示的 XML 实现策略,并对信息传输技术进行了分析。
文摘By taking Daan city in Jilin Province as a research object and by using TM image in 1989 and ETM + image in 2001 from American LANDSAT satellite,all kinds of maps and documentation,information of grassland,saline-alkalized land,cropland,water area and forestland is extracted by man-computer interactive interpretation method with ArcView and ArcInfo GIS software, and statistics data is acquired. On the basis of this the changing trend of land use types in the next ten years is forecasted and analyzed with Markov model. The results indicate that the problem of grassland degradation in the study area is quite serious.
