28.9.00 Aufbau GeoWorld 5 - Mettenmeier GmbH

18 GeoWorld Mettenmeier Aus den Projekten
GIS Service Prague Gathers
Experience on Mainz Project
The SW Mainz Project became
the first completely independently
led project of GIS Service
Prague spol. s r.o.
During the third quarter of 1999, work
on the SW Mainz project started at GIS
Service Prague spol. s r .o. company. The
goal of this project was to transform the
existing analogue and digital documentation
of the distribution system of gas
and water for the Stadtwerke Mainz into
a homogenous form enabling problemfree
conversion to the GIS system.
Project Parameters
Gas distribution network
length of main pipes
network (GHL) 680 km
number of service
connections (GHA) 34,000
Water distribution network
length of main pipes
network (GHL) 820 km
number of service
connections (GHA) 34,000
Project duration 3 years
Source documentation
analogue plans 1:500 (0.5m x 0.5m)
– database of field outlines in Microsoft
ACCESS system (total of 44,000)
– digital land register in the Micro-
Station format (*.dgn)
– existing digital documentation of distribution
networks in the Micro-
Station format (*.dgn)
System Selection and Data Structure
The system for conversion of documentation
and its maintenance is Micro-
Station (MS 95). In this stage of the project,
no external database information
are attached to the graphical elements
and all descriptive attributes are recor-
ded in the graphical file in the MS TAG
form. With respect to specific requirements
of the client it was necessary to
create a special application upgrade enabling
easier and error-free data conversion.
The processing unit (conversion, data
transfer, archiving) shall be square kilometer
(1 KiQu). In the framework of
this unit all digital documentation is
processed with the following data structure
in the MicroStation format (*.dgn):
– file of distribution networks Gas,
Wasser (g5032.dgn,w5032.dgn)
– file of digital land register (k5032.
dgn)
– file of thematic information (s5032.
dgn)
– file of the existing digital documentation
of distribution networks (gnd
5032.dgn)
Some data are processed by map sheets:
– file of discrepancies and errors upon
data conversion (5032410g.uns)
– file of map sheet frames in the scale
1:500 (g5032410.dgn)
Data Conversion
Digitalization
The digitalization itself is carried out
according to the valid rules delivered by
the customer. In the first stage, the network
main pipes network and subsequently
service connections are converted.
To assure location accuracy given by
the digitalization regulation a pre-construction
of the distribution network is
carried out. Maximum permitted error
in pipe location is 1m. A further step is
drawing-in the networks with subsequent
creation of objects and attachment
of descriptive attributes (pipe diameter,
year of built, pipe material, specific
information on pipe, etc.). After
complete creation of objects, the pipes
are dimensioned. For unclear places,
details are digitized, and for illustration
of height conditions section details are
digitized. During digitalization all discrepancies
in existing documentation
(missing information, dimension errors,
etc.) are documented using error symbols.
During digitalization, error symbols
proved to be an important tools for
good development of the project.
Thanks to internal structure (symbol
with descriptive attributes in the MS
TAG form) they enable not only documentation
of discrepancy from the side
of processor but also documentation of
solution from the customer’s side.
Check of Digitalization
In the first stage, a detailed visual check
of the content of printed map sheets is
carried out. With respect to the fact that
some prescribed combinations of graphical
attributes cannot be controlled
using the software, printing of map
sheets is carried out for the needs of
visual check with special color setting.
In the second stage, software proof is
carried out. It includes, among others,
check of syntax of individual graphical
elements, correctness of graphical attributes,
etc.
GIS Service Prague ist eine Tochter
der Mettenmeier-Unternehmensgruppe
und vom tschechischen
Partner Martin Hrdlička
Illustration of
documentation of
discrepancies using
error symbols