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Modeling and representing spatio-temporal process is the key foundation for analyzing geographic phenomenon and acquiring spatio-temporal high-level knowledge. Spatio-temporal representation methods with bottom-up approach based on object modeling view lack of explicit definition of geographic phenomenon and finer-grained representation of spatio-temporal causal relationships. Based on significant advances in data modeling of spatio-temporal object and event, aimed to represent discrete regional dynamic phenomenon composed with group of spatio-temporal objects, a regional spatio-temporal process description method using Top-Down Hierarchical approach (STP-TDH) is proposed and a data organization structure based on relational database is designed and implemented which builds up the data structure foundation for carrying out advanced data utilization and decision-making. The land use application case indicated that process modeling with top-down approach was proved to be good with the spatio-temporal cognition characteristic of our human, and its hierarchical representation framework can depict dynamic evolution characteristic of regional phenomenon with finer-grained level and can reduce complexity of process description.

Being short of evolution mechanisms, theories of spatio-temporal representation and modeling have great challenges to describe and represent the continuity and gradual geographical entities, still less deeper information retrievals and knowledge mining. The spatio-temporal dynamic semantics, which contains geographical entities, changes of entities and evolution mechanisms, is presented. According to the intrinsic process characteristics of dynamic entities, a hierarchical semantics structure and process object sequences included by level are given. This paper describes the process relationships and behaviors, and formalizes them into evolution operators, which subdivide into the process recurrence operators and recurrence ones. Based on the object-oriented technologies, the evolution operators are integrated into process object sequences, and a process-oriented dual representation framework on process objects' recurrence and recursion (DRF-PORR) is presented as well. And finally, as a case study, the typical oceanographic phenomena are taken to carry out the case modeling.

In this paper, we investigate the use of a family of transform domains in embedding hidden data.A new date hiding scheme that is based a pair of unmatched orthogonal transforms has been developed. The hidden message signal is transmitted via the residual channel of two different parameterized slant transforms. The properties of residual channel of parameterized slant transforms are characterized and performance of proposed scheme have been analyzed and simulated. We also discuss on the performance of the scheme and basis selection.

Integrative management of massive spatio-temporal data and the relevant capabilities for time series analysis are important research targets of new generation GIS software architecture. At present, solid developments are imperatively needed in technology for effective organization and storage of massive spatio-temporal data. Oriented to spatio-temporal multi-dimension structure, a massive spatio-temporal data seamless organization and storage model based on spatio-temporal partition (STP), spaito-temporal clustering (STC) is presented, and the test on single table of 2GB to 60 GB shows that integration of STP and STC can improve performance of spaito-temporal search effectively.

The spatial data are processed via editing, query and other complicated analysis with spatial arithmetic operators provided by Oracle Spatial and SQL. In general, abnormal conditions will not occur in the operation with spatial arithmetic operators. In case the number of points of a polygon reaches 60000 or the number of inner rings of a polygon exceeds 200, errors may occur in the intersection overlay operation for spatial geometrical data and the connection between the system and Oracle database will be interrupted. For specific situation of GIS application in China, a polygon of a single parcel, as may occur in land resource investigati on, sometimes includes 90000 points, even exceeding 120000 points, and the number of inner rings may far exceed 200. A bug is discovered by the authors in the application of spatial overlay analysis on the national city and county administrative map and national land use map at scale of 1:4000000. After a lot of tests and discuss with Ora cle Corporation, the bug is finally confirmed by