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DESIGNING AN OPTIMAL AND SCIENTIFIC GIS PROJECT 
Bishwa Acharya, Ph.D. C.P. 
Technical Program Coordinator 
William C. Bell, Ph.D. 
Senior Public Research Associate 
Government Information Systems Laboratory 
Carl Vinson Institute of Government, University of Georgia 
201 North Milledge Avenue Athens, Georgia 30602 USA 
Commission III 
This paper will address the main ingredients of a scientific GIS such as: datum, map projections, 
geodetic controls, scale, information components, interchange of digital information, and 
accuracy standards. 
Key words: Scientific GIS, Datum, Geodetic Control, Map Projections, Map Scale, Data 
Interchange 
INTRODUCTION 
Many terms have been and are used to express integrated 
and geographically (geodetically) referenced digital mapping 
systems. Examples include: 
€ Land Information System (LIS), e Geographic 
Information System (GIS), € Spatial Information System 
(SIS), € Land Related Information System (LRIS), € Multi- 
purpose Cadastre, € Land Record System, e Computer 
Aided Mapping Systems (CAMS), € Modern Cadastre, ® 
Land Record and Resource Information System, € Land 
Data System, € Geographic Data Bank, € Land Data Bank, 
€ Land Record Information System, e Community 
Geographic Database, € Automated Mapping System, e 
Automated Information Management System, € Geomatics, 
€ Geoinformatics, € Geometronics, and 
€ Spatial Information Mapping and Analysis (SIMA). 
Of the many terms used, two terms, land information system 
(LIS), and geographic information system (GIS) have 
ultimately become very popular and acceptable to the 
surveying and mapping and allied communities. Both these 
terms are frequently taken as being synonymous. To some 
extent, this is correct, but the term GIS defines a broader 
area that includes statistical data and modelling. LIS is 
solely a land-based information system but GIS covers any 
information which is geodetically referenced and includes 
land information or other information. Therefore, an LIS is 
a part of a GIS. GIS can be defined as a computer-based 
System to capture, process or manipulate, store, edit, and 
display information (data) which is geodetically referenced. 
The function of a geographic information system is to 
process or transform raw data into information in a 
geodetically referenced form which will assist the decision 
maker in reaching an optimal decision (planning, design, and 
implementation). 
The term GIS has also been used by some as a tool for 
information management without giving any consideration to 
the spatial identity of the information. To distinguish a GIS 
from computer-aided graphics we have used the term 
"Scientific GIS". A scientific GIS is defined as a spatial 
information system which uses the principles and meets the 
standards of the surveying and mapping sciences. Also, GIS 
is divided into three broad categories according to the 
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objectives, capability of capturing information, and accuracy 
standards of the products: 
© global 
© regional 
€ local 
Global or international GIS are generally small scale GIS 
whose objectives may be to study the figure of the earth 
(gravitational field), scientific research, navigational 
applications, environmental planning etc. 
Regional GIS is a medium scale GIS, whose objectives may 
be to provide better information to planners, engineers, and 
earth scientists about the natural resources available (which 
are needed for all modern development works and ultimately 
to improve the quality of life) in a region, and to provide a 
regional approach for solving problems such as: flooding, 
accelerated erosion, environmental and ecological studies, 
population growth, etc. 
Local GIS is a large scale GIS, whose objectives may be 
planning, design, execution, and maintenance of any limited 
area development project. 
À generic GIS consists of the following fundamental 
components: 
€ Geographic or geodetic component 
€ Information component 
© System component 
® Accuracy standards. 
GEODETIC COMPONENT 
This component of GIS transforms information into a well 
defined reference system and checks the accuracy of the GIS 
products. The following factors comprise the geodetic 
component: 
® datum/reference surfaces 
® selection of mapping plane 
® scale of base maps and map numbering system 
® geodetic controls required to tie the map frame (or to 
define the mapping plane) to the mapping plane and the 
datum/reference surface.