International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B4. Istanbul 2004 
Interndi 
2.2 Object-Oriented and Flexible Architecture 2.7 Data mining and knowledge discovering from spatial object r 
; : ; ; interfac 
Object-Oriented theory and programming provide a powerful Interoperability is the capacity to access multiple resources applica! 
way of modelling the structure of information in SDI. The through common approaches to allow interaction of the wide is appl 
mechanism of abstraction, inheritance and polymorphism variety of information technologies. Interoperability is defined provide 
makes an object-oriented GIS capable of protecting private in standards, through agreement on terminology; adoption of importi 
information as well as opening public methods of geographical defined protocols, and through distributed services on the this lay 
objects in SDI. More over, by object-oriented modelling, it is Internet. Interoperability allows simultaneous use of multiple standar 
very easy to map the digital object to the real object of the geo-spatial data sets without needing to change the underlying languag 
world and to understand the behaviours of queries and analysis digital resources. As users request data from multiple digital COM/L 
for various users. A GIS platform for SDI development should resources the interoperability is apparent as the responses from custom 
be in flexible architecture, extensible and easy for 
customisation. 
2.3 Dynamic, multidimensional and real-time 3D 
visualization 
SDI is a platform providing geographical information. It also 
has to provide "user interface" for various users to view the 
information. As DEM and 3D models are fundamental 
information in SDI, ready-to-use 2D display or 3D rendering 
tools are essential for GIS software for SDI. As is described in 
Al Gore’s speech, users can view the earth from the space and 
zoom into a city, even a building. If the network bandwidth is 
broad enough in future, some real-time information such as 
running cars can be also viewed through the platform. So, SDI 
should have the capacity of integrating dynamic information. 
2.4 Multi-scale representation 
For applications, the collection and/or integration of spatial data 
each of the various digital resources can be combined in a 
standard Web Browser. This allows a user to request land, 
water and political boundary data from different sources and 
overlay the data with geographic accuracy, producing a product 
specific to the user's application. 
2.8 Federated spatial databases 
SDI is not an isolated system, but a distributed system with 
huge volume spatial data and related attributes data on wire and 
wireless computer networks. It is necessary to develop a 
distributed, heterogeneous and autonomous federated spatial 
database management system and to solve the data accessing of 
distributed heterogeneous component databases transparently, 
the data handling in collaboration in the aspect of spatial -data 
operation, analysis and representation as well as the data 
delivering from data providers to end-users by web and mobile. 
3. GEOSTAR: A GIS SOFTWARE FOR DEVOLOPING 
  
at a wide variety of scales are very fundamental. The land use SDIS Fig. 2 
management in national, provincial and local level needs standai 
different accuracy. The multi-scaling representation with LOD 3.1 Main Features the sat 
technique in GIS software is a necessity. image 
GeoStar is a GIS software which is developed by Wuhan applice 
2.5 Data fusion and information fusion University, the former Wuhan Technical University of Custon 
Surveying and Mapping (WTUSM) in China since 1992. The or hy 
High level of data fusion technology has played an important latest version was 4.0 released at the end of 2002. The object- applicz 
role in utilization and development of increasingly complicated 
data like multi-source image. For instance, the relatively high 
resolution of SPOT panchromatic images is suitable for 
1:50,000 land cover investigation, however, they have no 
spectral information at all. On the other hand, Landsat TM 
images possess rich spectral information and have been used for 
land cover classification for a long history, but their low spatial 
resolution limit their usage for 1:50,000 landcover investigation. 
Information fusion technology fuses these two kinds of images 
oriented technology has been widely applied in the design and 
implementation of this software. There are seven major aims of 
GeoStar version 4.0 when designed. They also form the major 
features of this version of GeoStar. These features reflect the 
latest achievements of IT and object-relational database 
management system. These features are: 
® Able to provide solutions for enterprises with image, 
vector, DEM and 3D models integrated into a single 
application 
  
and the image fused is of spatial resolution as the SPOT image e Supporting object-relational database management m 
while keeps the spectral information as TM image. System to manage massive spatial and attributes data, 
e With flexible architecture supporting both B/S and/or C/S 
2.6 Data mining and knowledge discovering from spatial applications, 33 D 
DB e Can be run in both Windows and Unix operation systems, 
e Based on COM technology and easy for customization, 
An SDI should provide a mechanism for users to navigate and 9 With built-in 3D modeling and visualization tools, OGC 
search for geospatial information. Especially, the automatic : ; : eogra 
; t Beosp i SP diam ® Compatible with old versions be | 
interpretation of image and the extraction of semantic and non- : systen 
semantic information from images need the intelligent decision- 3.2 Architecture As Ge 
making support of GIS. Fortunately most of the knowledge : : : i. yee image: 
§ sap ety. most ol 8 GeoStar v4.0 is 4-tier architecture as shown in Fig 1. The first £c 
needed for expert system (ES) just exists in GIS database : ; develc 
nb ui : Cg ee layer is database SDC/ODBC layer. Both spatial and attributes 
implicitly, and which provide a mutual facilitative and ; ; model 
; : : : ; are stored and managed in commercial relational database. For ; 
interactively integrated environment for ES’s development and specifi 
applications. 
compatible purpose, data can also be in file format of lower 
version of GeoStar. The second layer is spatial COM/DCOM 
layer that contains kernel components of this system. The 
rationale of spatial semantics and primitive operations are 
implemented in this level. An extended OGC simple feature 
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