International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B-YF. Istanbul 2004
5.1 THE INSTALLATION OF A GIS FOR THE
TOWNSHIP OF ARZEW
according to the available data and the existing means the
realization of the Prototype Communal GIS of Arzew takes
the three following phases as a basis :
5.1.1 Data Organization Phase
The organization of data and their modelling rests on the
SRT, as presented in the section (8. 3) of this publication. In
this context the data base on the Communal GIS of Arzew
includes several data, that are represented under shape of
layers according to the available initial data :
General data :
- A Plan of the structure
- Plan parcels
- Parklands
- The postal addresses
- Topographic plan
- Aerial photo
Data of networks :
- A Plan of axes of streets
- Networks of drinking water
5.1.2 Data Seizure Phase
Maps and the existing plans are the essential sources to the
construction of our GIS, and to the creation of the different
layers. The geometric whole is constructed from the
different information numérisation representing on these
plans and that appearing to be useful for our application.
Before their definitive storage and their use in our system,
the spatial data underwent pre-treatments: conversion of
data structure, unification of the projection system.
5.1.3 System implémentation Phase
In accordance with our identified needs, vector GIS, DBMS
Relational Multiconnexion and a footbridge to stock and to
manage data multi-users georeferenced. And in order to
validate the retained solution, the application will be driven
under the following environments :
| - Software Arcview® 3. 2 : The choice carried on this GIS
because, on the one hand it offers the possibility to adjust to
our problematic and the available data, on the other hand, it
is available to the CNTS. Besides, it gives the possibility of
the access as customer to the distant data according to
architecture client/server (Fig. 3).
2 - Software Oracle® 8i: Multiconnexion Relational DBMS,
constitute an operational platform of production, permitting
to publish a data base easily on the network, assuring an
optimal transition traditional of the client/server thus toward
network architectures. It also allows files of all nature to
benefit from the security and the integrity of the data base
(83. 5).
3 - ArcSDE® 8. 0. 2: (SDE: Spatial Database Engine) It is
the footbridge between the Multiconnexion Relational
DBMS and the software GIS. The SDE permits to stock the
spatial geometry (points, lines, polygons. ) and data
attributiveses within a same relational data base, Oracle,
Informix, IBM DB2, Sybase or SQL Server. It lets then to
the Relational DBMS the care of the management and add it
a certain number of specific geographical operators. it
allows the relational data bases to understand and to exploit
the spatial information.
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To concretize the proposed solution we worked to the side
Client ArcView® 3. 2, with its own Avenue® programming
language to create a convivial work environment (Fig. 5),
this last permits of :
- To facilitate the access to information;
- To execute requests according to the right of
access;
- To assure a fast and convivial communication for
the client (user of the local geographical
information), either locally either to a distant data
base.
In order to keep the set of clients (group of partners) in the
same work context, this environment of work has been
created like being an extension!" supplementary for the
software ArcView®, its gives the possibility to transfer this
environment on the set of clients joined to the network and
connected to the Oracle RDBMS.
(1): Extensions permit to share personalizations, documents
or all other object, independently of a project. Extensions
can be easily, intuitively used and created by all person
knowing the language Avenue [ESRI 1996].
The main menu, allows the user to reach in a simple manner
and predefined to data that interest him, while placing at its
disposal the set of functions allowing him to do its tasks. it
is composed of five elements :
ERSTE
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Llama dei |
Fonts fuidap ey
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Faust se |
Figure 5. The Main Menu
Classes of entities : allows the user to choose the entity on
which he wants to visualize or to do requests.
Public Functions : to see the available and responsible
public functions on classes of entities selected.
Products : maps of the township, the cadastral plans, the
aerial photos, orthophotoses, etc..., with which the user
wants to work.
Zone of work : allows the user to define the geographical
zone of the township, in which he wants to select and to
visualize data, to do its treatments or its cartographic
reproductions, precisely. According to the available data for
this application, we divided the zone of work in five under
zones: Complex zone, Zabana zone, the center city, Plateau
zone and the industrial zone.
Closing : this function permits to leave the application, with
a registration of modifications under the index of work
named ARZEW in the user's disk root.