summaries
Ananda Abeydeera - Cartography as a vital element of ad-
ministration in the Dutch Colonial Government of Maritime
Sri Lanka 1658-1796
According to the terms agreed upon in a treaty of 1638 be-
tween the King of Kandy and the Dutch East India Company,
the Dutch were to expel the Portuguese. In exchange they
were to be awarded exclusive trade concessions including the
lucrative cinnamon trade. After twenty two years of fierce
struggle the Dutch finally drove the last forces out of Sri
Lanka and considered themselves masters of the territorial
possesions wrought from the Portuguese. The Company held
these territories contrary to the will of the King and conse-
quently they were in almost continuous conflict with each
other on territorial issues, acces to seaports, right to harvest
cinnamon in hinter/and woods and the capture of elephants
in the open jungle.
By measuring and surveying the coastlines with unprecedent-
ed accuracy, the Dutch produced in 1659 for the first time in
the history of the mapping of Sri Lanka a map with the pear
shaped, almost modern, outline of the island.
The body of cartographic material produced during the near-
ly 150 years of Dutch administration is remarkably prodigious
and it was these maps that the colonial government relied
upon in its day-to-day exercise of administration.
A study of material, of which major holdings are preserved
in The Hague and Leiden together with collections in a num-
ber of other European cities, is of great significance both for
the study of the history of cartography of Sri Lanka and for
the history of the Dutch colonial administration.
P. Windey - Photography and electronics in cartographic en-
terprises
As in most graphic applications, electronic Systems are also
being introduced in cartography now. However, for map mak-
ing a few specific requirements have to be taken into account,
such as precision and dimensional stability for large sizes. In
this sector the success of electronic Systems depends on the
cost of memory and storage capacity, the inßuence of image
resolution on the System 's productivity, the System cost and
the requirements of the user.
Physical images require a lot of space in an electronic System.
Films - with their excellent image quality - are much cheaper
storage media than hard disks or Computer tapes. Data stored
off-line on Computer tape do not have a shorter access time
than Photographie film. Recording on tape cartridges is
cheaper, but searching the data takes a lot of time. Registra
tion on WORM optical disks is expensive and the image
quality is lower than on Photographie film. The use of an
erasable optical disk is even 50 times more expensive than
Photographie film.
In general, image processing is still time-consuming and may
reduce the capacity of a System considerably. For image input
and Output high precision equipment is needed, and the hard-
ware costs will not be low. Yet, there is an evolution in system
costs. The costs of hardware appear to be relatively stable,
but the Software costs (particularly for a specialized applica-
tion such as map making) are increasing. Software now takes
some 80% of the total system costs.
Before deciding to invest in electronic produetion Systems car-
tographers still have to find a Solution to a number of Prob
lems. Will the new system be profitable? Should its capacity
be adopted to the highest, the average or the lowest work vol-
ume? What about compatibility with existing equipment and
data exchange Standards?
Electronic Systems will find their way to many cartographic
companies, but Photographie film will still be used as the ap-
propriate Information carrier. To funetion well in the modern
cartographic process, the films have to be adopted to elec
tronic techniques. The Photographie process may evolve to a
'back-end' process, supplying the recording medium for the
data to be processed by electronic produetion Systems.
B.J. Köbben, J.M. Osinga H.J.H. Tappel - CES: a carto
graphic expert system for symbol selection
CES is a front-end expert system for the geographic database
of the national Physical Planning Agency (RPD) of the
Netherlands. It is designed to help users of this database to
choose appropriate symbols with which to map selected vari
ables. CES determines symbol appropriatness by considering
the properties of these variables and selects suitable symbols
from the available symbol library.
Then, the system asks the user for the intended purpose of
the map. With the result of that query a multi-criteria evalua-
tion is carried out on the symbols selected. This results in a
presentation of the symbols in order of their suitability. Last-
ly, the user makes the final selection of symbols based on his
own taste.
While developing CES, the authors came across the limita-
tions of existing cartographic theories on symbol selection.
Therefore they developed a model for automated symbol
selection which is presented in this article.
Currently, CES is used as a prototype in the Offices of the
RPD in Zwolle.
Yingming Zhou - The Statistic Cartography Expert System
and its application for the National Economic Atlas of China
The Statistic Cartography Expert System is an intelligent
Statistical mapping program. It 's a combination of Statistical
mapping tools together with an expert system. The knowledge
base contains rules about thematic mapping, Classification
and symbol choice and display. The system runs on a PC, us-
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KT 1991.XVII.1
