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SPATIAL DATA MODELING and PROCESSING for CYBER CITY

Modeling and processing digital data: three-dimensional GIS models, multi-scale data models, digital terrain modeling, spatial relations modeling, data quality and uncertainty of spatial data, image fusion, spatial data mining;

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Selected recent publications

Shi, W.Z., Dai, E.F., Li, Q.Q. and Zhu, C.Q. (2005).  Estimating the propagation error of DEM from higher-order interpolation algorithms, International Journal of Remote Sensing. (Accepted).

Zhu, C.Q., Shi, W.Z., Li, Q.Q., Wang, G.X., Cheung, C.K., Dai, E.F. and Shea, Geoffrey Y.K.  (2005).  Estimation of average DEM accuracy under linear interpolation considering random error at the nodes of TIN model, International Journal of Remote Sensing (Accepted).

Yang, B.S., Shi, W.Z., and Li, Q.Q. (2005). An Integrated TIN and Grid Multi-resolution Model for Digital Terrain Representation, International Journal of Geographical Information Science (Accepted).

Yang, B.S., Shi, W.Z. and Li, Q.Q. (2005).  A Dynamic Method for Generating Multi-Resolution TIN Models, Photogrammetry Engineering and Remote Sensing (in press).

Shi, W.Z., Cheung, C.K. and Tong, X.H. (2004).  Modeling error propagation in vector-based overlay spatial analysis, ISPRS Journal of Photogrammetry and Remote Sensing, 59(1-2):47-59(EI).

Shi, W. Z., Fisher, P.F. and Goodchild, M.F. (2004).  Recent developments in modeling uncertainties in geo-spatial data and analysis, Photogrammetric Engineering and Remote Sensing, 70(8):919-920(EI).

Shi, W.Z., Cheung, C.K. and Zhu, C.Q. (2003).  Modeling error propagation in vector-based buffer analysis, International Journal of Geographic Information Science. 17(3):251-271.

Shi, W.Z., Yang, B.S. and Li, Q.Q. (2003).  An Object-Oriented data model for complex objects in three-dimensional Geographic Information Systems. International Journal of Geographical Information Science. 17(5):411-430.

Pang, Y.C. and Shi, W.Z. (2002).  Development of Process-based model for dynamic interaction in spatio-temporal GIS, GeoInformatica, 6(4):323-344.

Shi, W.Z. and Pang, Y.C. (2000).  Development of Voronoi-Based Cellular Automata ¡V an Integrated Dynamic Model for Geographical Information Systems. International Journal of Geographical Information Science. 14(5):455-474.

Shi, W.Z. and Liu, K.F.  Modeling fuzzy topological relations between uncertain objects in GIS, Photogrammetric Engineering and Remote Sensing, 70(8):921-930(EI).

Shi, W.Z. and Liu, W.B. (2000).  A Stochastic Process-Based Model for Positional Error of Line Segments in GIS. International Journal of Geographical Information Science, 14(1):51-66.

Shi, W.Z. (1998).  A Generic Statistical Approach for Modeling Errors of Geometric Features in GIS. International Journal of Geographical Information Science. 12(2):131-143.

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Recent research grants

09/02-08/05 Analysis of the inner structure of Hong Kong¡¦s urban heat island. RGC, HK$ 513,000.  Janet NICHOL (PI), Ernesto JAUREGUI and Baki IZ.
06/98-05/03 Data models for three-dimensional geographic information systems, RGC,  HK$ 720,000.  John SHI (PI) and Q.Q. LI.
06/97-12/99

Development of an advanced model for handling complex objects in GIS. RGC, HK$ 435,600.  John SHI (PI).

08/95-09/98 Handling Uncertainties in Geographical Information Systems and Remote Sensing Integration. RGC, HK$ 337,990.  John SHI (PI).

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Selected projects on Spatial data modeling for cyber city

Data models for three-dimensional geographic information systems,

John SHI and LI Qing-quan

This project aims to develop a 3D approach which can handle 3D real world entities in GIS, including the development of an Object-Oriented 3D (OO3D) data storage model (Figure 37). The following are the specific objectives:

1.             To develop a 3D conceptual data model theoretically,

2.             To develop the physical 3D models technically for various applications, and

3.             To conduct an application case study to using the developed models.

Figure 37.  An example of a 3D city model based on the developed OO3D model

Development of an advanced model for handling complex objects in GIS.

John SHI

An object is described by its spatial, temporal and attribute elements with multi-level description. Such an object is defined as a complex object in this study. Current GIS normally only handle objects with spatial and attribute components within a fixed scaled ¡V simple objects. The scope of this study is modeling of complex objects for GIS. It is the aim of this project to develop an advanced GIS model handling complex objects. Two research issues will be investigated: (a) incorporating temporal components to the existing GIS models; and (b) describing relations between the complex objects. The project is carried out in the following two phases: developing the conceptual advanced model, studying the implementation framework.

Handling Uncertainties in GIS and Remote Sensing Integration.

John SHI

The confidence volume model for three-dimensional linear features in GIS was developed by Shi (1997) for the first time in GIS research. The model represents a confidence volume of an arbitrary point on the line segment. The volume of the line segment was thus derived based in the confidence volume of the point that constructs the line segment. This error model directly represents the confidence volume for a three-dimensional line segment. It gives a volume around the measured three-dimensional line segment. The true location of the line segment is included within the area with probability larger than a pre-defined confidence level.

Shi (1998) further generalized and developed a generic model for one- to N-dimensional features in GIS. This finding is internationally regarded as the definitive reference for error modeling in spatial data.