SYSTEMS FOR INTEGRATED GEOINFORMATION: 
stages of evolution 
Morakot Pilouk 
International Institute for Aerospace Survey and Earth Sciences (ITC) 
P.O. Box 6, 7500 AA Enschede, The Netherlands 
Tel. +31-53-4874358, Fax +31-54-4874335 
E-mail: MORAKOT@ITC.NL 
XVIII ISPRS Congress, Commission Il, Working Group 2 
KEYWORD: GIS, Technology, Design, Systems, Vector. 
ABSTRACT 
The evolution of geoinformation technology in the last decade has resulted in a rapid change in the way geoinformation can 
be used and presented. The technological development stimulates the coherent use of information from multi-sources with 
multiple themes and dimensions to answer questions that demand increasingly complex spatial analysis. This requires to have 
a powerful geoinformation system (GIS) that can efficiently integrate, manage, process and present different types of 
geoinformation. The paper points out the importance of an integrated spatial model that well-represents real world objects 
and relationships among them. An integrated spatial model is considered a very important basis of a GIS. Four variants of 
system architecture are distinguished corresponding to different levels of integration. The variants are discussed with respect 
to fourteen criteria. Further development should be directed to structural integration using the integrated spatial model as a 
basis, as being the most promising approach. 
1. INTRODUCTION 
The scientific study of the earth to improve human's living 
conditions, the quality of life and to prevent or mitigate 
hazards and disasters by exploiting modern digital 
computing technology requires to represent the real world 
aspects under interest in a digitally constructed spatial model. 
Using a tool set provided by a GIS, a spatial model can be 
constructed and may allow to virtually perform many tasks 
that otherwise would be carried out in reality, which may be 
too difficult, too expensive or destructive. A high quality 
spatial model that represents well all relevant aspects of 
reality, i.e. real world objects of interest and relationships 
among them, is needed to make the results obtained from 
operations on the model comparable to actual operations in 
reality. The richness of operations on the model, which 
reflects the functionality of the system, depends on the 
complexity of the spatial model. As such the spatial model is 
decisive basis of the system. In present practice, many GISs 
tend to be developed by combining different spatial models 
and related functions such as for modelling of terrain relief 
and 2D terrain characteristics with thematic aspects (e.g. 
colour, texture). This is achieved by using digital terrain 
model (DTM) sub-system and typical current GIS software. 
The approach implies a spatial model whose components 
are still separately stored and are loosely related. As a 
consequence the model is not robust and may not well- 
represent the real world aspects. 
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In general, a GIS should be aiming at integration of all 
necessary elements for the spatial model and functions to 
efficiently create and utilise the spatial model. This paper, 
therefore, analyses architectures of GISs in order to assess 
their present status and development trend, which may help 
to define the direction of the related research and stimulate 
development of GIS that can easily be used. The first part of 
this paper reviews general aspects of GIS with a brief outline 
of its functional components based on the user-perspective. 
The main concem is system usage, investment, maintenance, 
productivity and reliability of information. With respect to the 
robustness of the spatial model as a basis of GIS as well as 
taking into account present development in information and 
communication technology, four evolution stages of system 
architecture for GIS are distinguished ranging from loosely 
constructed to the well constructed systems. 
2. GENERAL ASPECTS OF A GIS 
A GIS is to be used to produce a spatial model in a form of 
database which contains a selective set of aspects of reality. 
In addition to the production role of a spatial model, a GIS 
should also play an interface role between human users and 
the database. This role includes data entry, information query 
and presentation. Data entry translates human knowledge 
into a component of the model conforming to the data 
model and data structure. Information query performs the 
reverse operation by translating the electronic components 
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B2. Vienna 1996 
  
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