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analysed to prepare the functional specifica 
tions for the new land information system. 
Because information planning and analysis is 
a complicated matter, many methods and 
techniques are developed to support these 
activities. In our courses for lad information 
we train the students in using these methods 
and techniques, we train them in the planning 
of information supply and in the functional 
design of new or improved land information 
systems. 
In our group some research projects are 
carried out like: 
- analysis of the land information supply of a 
middle sized municipality; 
- information analysis and planning of dif 
ferent applications of land related activities 
in municipalities; 
- information analysis and planning for en 
vironmental information, sea-information, 
etc.; 
- information analysis and planning for natio 
nal cadastral projects in different countries 
(e.g World Bank project). 
3.2 Data in GIS/US 
The research on data is based on the fact 
that most land information systems are decen 
tralized. 
There are thousands environmental informa 
tion systems with location oriented informa 
tion. The same situation occurs with sea- 
information systems. Within one municipality 
we detected hundreds of land information 
systems. There are hundreds of utility informa 
tion systems in the Netherlands. One of the 
goals of our research is the improvement of 
the exchange or combination of data in dif 
ferent systems. We are more or less develo 
ping a language to do so. Another aim of the 
development of data theory is the conversion 
of textual to graphic information, from raster 
to vector data and so on. The main topics of 
the data research are standardization, re 
search of accuracy and structuring. Because 
there are so many different date elements in 
LIS/GIS, we divide them into basic information 
and specific information. Our theoretical 
research is only aimed at the basic informa 
tion. • 
The main criterion to determine whether a 
piece of data belongs to the basic information 
is that it is used by more than one user. 
Other considerations may plaÿ a role in the 
determination of basic data. A data element 
can be so important for the organization of 
certain processes that it may be decided to 
record them in a basic registration. Besides 
basic data, specific data are determined. 
In combination with the Netherlands Council 
for Land Information, with the Society of 
Dutch Municipalities and with the Institution 
for Norms and Standards, we try to develop 
a complete classification of the basic data. All 
the data elements in the different categories 
are divided into uniform classes. They receive 
a generally accepted name and a uniform 
description. Proposals are made for the best 
way of presentation of the data in information 
systems. Within this research so called stan 
dard exchange formats are defined. 
As already stated, the quality of data within 
land information systems appears not to be 
very high. In built-up areas we found that 70% 
of data were correct. The research is aimed at 
the necessary quality of land information, 
especially on the following aspects: reliability, 
precision, currency, completeness and rele 
vance. 
3.3 Methods and techniques for data acquisi 
tion 
One of the biggest problems in automating 
spatial information systems is the acquisition 
of digital data, in general one can say that 
about 75% of the cost of establishing a good 
LIS or GIS is the data acquisition. Therefore 
we do a lot of research in this field. The main 
topics of our research are: 
- high resolution remote sensing imagery: 
applications in LIS/GIS; 
- a vectorization and interpretation of the 
scanned map data; 
- computer added surveying using scanned 
panoramic registrations 
Remote sensing constitutes a set of techni 
ques for acquiring and analysing information 
about objects from the radiation they emit or 
reflect. Scanning systems installed on satel 
lites record and transmit imagery data repre 
senting phenomena related to the surface of 
the earth. However, remote sensing applica 
tions depend on spatial resolution of imagery. 
Data acquired by LANDS AT systems have not 
been accurate enough to be used in such 
processes like topographic mapping in scales 
1:50,000 or 1:100,000. Introduction of the 
SPOT system improves the situation signifi 
cantly. Its 10 m x 10 m resolution in panchro 
matic mode and capability to create stereo