REMOTE SENSING AND DIGITAL PHOTOGRAMMETRIC DATA INTEGRATION INTO A GIS 3-D
FOR MONITORING AND ANALYSIS OF AN URBAN AREA UNDER NATURAL DISASTER STRESS:
Florea Zavoianu - Faculty of Geodesy, Technical University of Civil Engineering Bucharest, ROMANIA
Cälin Nifu - Military Topographic Department, ROMANIA
KEY WORDS: 3D-Urban Model, Database, Change Detection, SIG, SIT 3D.
ABSTRACT
The paper presents the main principles concerning data bases referring to urban areas in view of storage, processing and
efficiently and quickly analyzing the effects of natural disasters (earthquakes, floods, landslides, fires etc.) using satellite
images, aerial photograms as well as large scale video images. 3D reference model is achieved for a defined area before disaster
and post-disaster. The models are based an a topographic data structure, which incorporate topological information, obteined by
stereoscopic exploitation of aerial photograms, information completed with data acquired from large scale topographic planes
digitization. The principle of detecting significant changes by comparing 3D models constructed before and post-disaster are also
described.
RESUME
Dans ce travail sont presentés les principes d'organisation des bases de données, sur la zone urbaine, en vue de stocker, traiter
et analyser en mode efficace, rapide et précise des effets dues au désastres natureles (tremblements de terre, inondations ,
incendies etc.) en utilisant les images satellitaires, photographies aeriennes de même que les images video à grande échelle. Un
model 3-D de référence est construit, pour une zone urbaine bien définie, fondé sur une structure de données
topographiques et l ‘informations topologiques, obtenue par l'exploitation stéréoscopique de photographies aeriennes compléts
avec les données obtenues par digitisation des plans topographiques à grande échelle. Sont déscrites de même les principes de
detection des changements significatifes obtenues par comparaison aux medèls 3-D construites avant et post désastres.
1. INTRODUCTION
The monitoring and evaluation of natural disaster
(earthquakes, floods, landslides, fires) and the consequences
on urban areas is a complex problem that need the analysis of
a large volume of data of different types and accuracies.
A technical and economic data basis must be conceived for
the complex analysis of the data. They can stand as a support
for administrative decision making.
The analysis that could be done must consist of different
detailing levels according to the level at which decision is
imposed. Homogeneous data sources for large areas and the
possibility of rapid efficient and precise selection must be
used, in order to organize a Geographic Information System
(GIS) for large surfaces aiming to identify areas with major
changes in which the third dimension is the time and the
obtaining of a detailed analysis of 3D model in which the
fourth dimension is time. The analyze of urban areas
performed is a complex problem that is why SIT-3D consists
besides 3D model ( that is the cartographic data technical basis
concerning topographical details of informations concerning
terrain use, natural resources, terrain value as well as data
bases referring to low pollution sources and environment
factor concerning pollution, atmospheric factor and local
climate, social and economic factors concerning distribution,
occupation and the structure of population concerning
administrative office and last and not least the quick response
plans for different public services.
Thus results the multi and transdisciplinary, multiinstitutional,
multijuridical system, combining the centralized
administration of these data organized in a SIT 3D system to
autonomy and departmental responsibility (that provide of
specific levels of information from SIT 3D general information
system regarding practical applicability of decisional system.
Data distribution will be performed by a main server for a
town and the departmental server will store only department
interest data as for instance telephonic lines at the
telecommunication department, road network at road
department etc. At present these data bases are distributed
between many organisms on computing system of different
structure and they do not form a GIS integrated system that can
be consulted analyzed and updated centralized. 3D SIT system
is operation if it is combined with a user interface that allows
3D rapid visualization. When building such a system, local
conditions, technical support given by the involved institutions
and organization and the social and economical strategy of
development must be taken into consideration. The available
computing technology and technical equipment, the existing
software systems, the staff together with different basic data
sources with different accuracies and contents that have to be
collected, stored, organized, processed and analyzed together.
That is why aerial and spatial recordings referring to
topographic areas must be processed, organized and analyzed.
The possibilities of storage , the contents time and space
analysis together with real time updating must be defined.
Also possibilities of integration, as well as the analysis of
different volumes and data types versatile mathematical
models able to describe the environment with complex
phenomena and processes that take place in the vital space of
the urban zone as well as the possibility of the simulation of
different phenomena and processes belonging 3D model
needed by GIS system at low scale is conceived on the basis of
remote sensing images exploitation with a large spatial
resolution in time while the necessary 3D model is achieved
on remote sensing means by using photograms on a large
scale. This system of organization on levels of informations
data bases has the possibility to integrate different data
sources in view of ensuring a complementary of information
sources of rapid efficient and precise analysis of temporal
changes appeared in object space.
762 International Archives of Photogrammetry and Remote Sensing. Vol. XXXII, Part 7, Budapest, 1998
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