J.P. Liu1, Z. Liu1, K.W. Tao2, Y. Wang2

1 - Institute of Geo-Spatial Information, Tsinghua University, Beijing, China

2 - Chinese Academy of Surveying & Mapping, Beijing, China


Since workflow technology can be used to manage and control complex GIS application, workflow management in geoprocessing applications has gained more and more attention recently.

Complex spatial information processes are always involved in E-government spatial information service. A well-defined spatial process helps applications in E-government to archive more effective plan and management. Comparing with the general information process, there are at least four main characteristics for E-government spatial processes as followings:

(a)Spatial processes are spatial data-centered.

(b)Comparing with non-spatial processes, spatial processes are usually more complex, and need to be supported by complex calculation.

(c)Most different steps of spatial processes are closely linked to one another.

(d)As steps of workflow, processes and their operation parameters need to be integrated.

By analyzing the main characteristics, the formalized definition and the model of spatial process for E-government spatial information service are given in this paper. In this paper, some core technologies of workflow management in E-government spatial information service such as abstraction and computer modeling of basic operations, spatial process control and monitoring, and management of process data are also studied. In order to manage and control complex E-government spatial processes, the authors try to give a new definition of the state, context, programming logic and UI for workflow management of E-government spatial information service based on the workflow reference model. According to the standards of Basic Services Model(BSM) and Web Processing Service(WPS), the design and definition of basic spatial operations for E-government spatial information service are introduced. The authors also propose the system architecture and work mechanism of the process control engine to manage process data. Based on Web Service technology, a number of approaches for software development as well as the integration design of basic spatial operation components are introduced to implement this architecture.

            Finally, a geoprocessing experiment of E-government spatial information service is introduced to illustrate and our proposed solution. And the results show that our solution is feasible and effective.