Some success has been achieved in the past three years
in the generalisation of the base topographic information
to create derived graphic and raster products at output
scales of about 1:10 000. The Landplan graphic to be
launched later in 1996 will accompany the Superplan™
service in over 20 OS agents’ premises across the
country. Superplan customers are free to choose the
centre, scale, orientation and other parameters of their
large-scale plot of any part of Great Britain.
Data Theme Derived National Products
Base Topographic Land-Line®
Information Superplan™
National Height Data Land-Form PROFILE™
Model
Address database ADDRESS-POINT™
OSCAR®:
Traffic-Manager
Asset-Manager
Route-Manager
Network-Manager
Road centre-line
database
Boundaries database Boundary-Line™
Combinations of the Landplan
above
Table 1. The major definitive Ordnance Survey
datasets and their derived products.
1.3 Keeping the database up to date
Customer Requirements: Maintaining the currency of
the databases is essential to meet the growing
Geographic Information Systems(GIS) market. To
manage this expectation the nation is divided into urban,
rural and mountain/moorland areas and a revision policy
is assigned to each. Urban change is surveyed within 6
months of its completion, rural areas and mountain
/moorland areas undergo a 5 and 10 year update cycle
respectively. Such update cycles are also linked closely
Service Level Agreements (SLAs) agreed with major
customer groups.
Agreements have been signed with local authorities (as a
whole), utilities and some government departments to
package selected data themes /products to better meet
their needs. Customers are now increasingly realising
that there are more applications of data that are of use to
them, simply because they have access to data. Thus
there is now more demand for innovative applications and
new levels of service such as the integration of a wide
number of datasets to support urban planning,
transportation, health, environmental protection etc.
Field operations: The database is maintained through
regular update using a variety of techniques based on the
OS GPS control network and is supported by a network of
90 field offices and contractors. The survey field offices
request, update and return data to the database using the
Digital Field Update System (DFUS) which is currently
being extended by pen-PC based PRISM units (Turner
1995). The maintenance of the data is the most costly
100
item of expenditure each year and further improvement in
OS cost-recovery will be very dependent on minimising
the cost of the update operation.
1.4 The Changing World
Technology: The environment we all operate in is
constantly changing as shown by the fact that technology
in the survey market has changed radically over the past
10 years. GPS is now expected to have a greater impact
on all our lives through the initiatives proposed by the
Clinton Administration in late March 1996. Already we
have witnessed combined GPS/video capabilities (Novak
1995) and other innovative approaches such as the use
of GPS mounted on bikes for utility mapping (Gilton et al
1996)
Technology now offers tools and services to an
increasingly wide range of potential data suppliers and
users. This presents us all with a fascinating future in
harnessing the power to bring benefit to everybody for all
types of services: environmental planning, land
development administration, visualisation, ‘virtual reality”
etc. The major advances in computing power, off the
shelf workstations and high speed have contributed to
significant the surges in technological progress. One
area of disappointment is the lack of any real progress in
the standardisation in operating systems.
Government and commercial factors: The environment
under which national mapping agencies operate is
increasingly challenging. Mapping agencies in the United
States and New Zealand have experienced the winds of
change during in the past 18 months. In both cases there
is increasing realisation that there is a need to reduce
costs and to commercialise operations so that there is a
return on the investment made by the taxpayer. In Great
Britain this has been the case for some years and
Ordnance Survey is now driven totally by this goal.
As an Agency OS agrees challenging objectives with
government at regular intervals. In its 1995 Agency
Framework Document (1995a) OS has specific objectives
which include “ maintaining the National Topographic
database " and ^" building a National [Geo]spatial
database ”.
1.5 Cartography or the real world?
Cartography: The OS digitising programme was
originally implemented to improve the efficiency of the
mapping and charting process. However the period from
the 1970s to early ‘80s also witnessed the concept of
flexible digital data emerge, this has had far more
potential than automated chart paper mapping. A whole
new industry has now developed to the development of
geographic data.
A legacy remains however, the digital topographic data of
many mapping agencies today bears witness to the
origins of the original objective of map production. The
data often resembles digital cartography rather than
digital geographic information. Many digital products
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B6. Vienna 1996
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