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M. J. Kraak - BACKGROUNDS AND POSSIBILITIES
OF CARTOGRAPHIC RASTER DATA STRUCTURES
In cartography, the use of raster data is increasing.
The quadtree is the most common type of raster data
structuring. The size of raster data bases has always
been and still is a major problem. Although methods
are developed to reduce the size of the data bases,
cartographic applications are still mainly limited to
small scale map- construction and mapping of remote
sensing (raster) data. Basic raster data manipulations
(e. g. parallel shifting, combinations and transfor-
mations) are often derived from remote sensing
image processing techniques and may be combined in
various ways for cartographic purposes. This paper
aims at providing an overview of these (and other)
aspects of raster data structures. It has been presen-
ted in Delft at a Study Day on computer-assisted car
tography organised by the Dutch Cartographic Society
(NVK) in April 1986.
Th. J. Poelstra and D. H. M. van Rijn - MODERN
NAVIGATION WITH TELE-ATLAS
The electronic publishing-firm Tele-Atlas is engaged
in collecting, processing and Publishing of road infor-
mation for large parts of Europe with the intention to
place this Information at the disposal of users on a
commercial basis. Users may need this Information
for traffic and transportation, but increasingly also
for building up land Information Systems.
The databases are created around three main aspects:
routes and distances, road network and public trans-
port. In this article most attention is focused upon
the applications of the road network database, built
up from line segments. A new System of "pre"-
surveying is described here as well. As very big
databases are created modern electronic means and
equipment (e. g. "CD-ROM") are applied whenever
feasible.
N. Wiedenhof and M. L. G. Thoone - CARIN: AN
ELECTRONIC CO-PILOT IN CARS
In the Geldrop Project Centre of Philips Research
Laboratories members of the Research Laboratories
and Audio Division staff of Philips are now taking
the first steps towards providing cars with an elec
tronic co-pilot which can plan the route, guides the
driver to his destination, knows the position of the
car and can specify it at any moment, and can also
provide a number of details about the environment or
the destination of the journey. The electronic system
has been given the name of CARIN: Car Information
and Navigation.
B. Buis, E. G. Greven and G. G. Spoelstra - THE
ELECTRONIC CHART
Developments are now taking place which will even-
tually lead to the gradual supersedence of the conven-
tional nautical Chart by electronic chart display Sys
tems. Manufacturers of electronic equipment have
already entered the market and hydrographic depart -
ments are now confronted with the huge task of
supplying the digital Information and making sure that
the new means of communication will be at least as
effective as the conventional Chart. The Hydrographic
Service of the Royal Netherlands Navy, in close
collaboration with other members of the North Sea
Hydrographic Commission, is paying a lot of attention
to the development and requirements of the electronic
Chart. This article may be considered as an interim
report of the results obtained in various studies up to
now. The main emphasis is on cartographic design,
i. e. on the specifications for the electronic chart,
and on the technical realisation of the desired way of
presentation.
The main conclusion was that the nautical Information
could best be split up into various levels. Next to a
basic level containing fundamental Information which
will always be displayed, the user may then choose
which other level(S) he wants to see represented on
the screen (CRT). Other characteristics of the elec
tronic Chart and aspects related to its introduction
(e. g. legal aspects) come up for discussion as well
and the article is concluded by the remark that a lot
has still to be done before the electronic chart will
actually replace the conventional one.
KT 1986. XII. 2
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