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Accumulation and Provision of Information on Natural Disasters and Disaster Reduction□■

3-7. Construction of the Asian Disaster Reduction Internet GIS
3-7-1. Background on the Development of the Asian Disaster Reduction Internet GIS
Increased reliability of information extracted from satellite images with the progress of image
processing technology in recent years is gradually establishing the environment for extracting various
information by remote sensing without restriction in time and place and using this information fordisaster reduction. At this point, no system which can be linked directly to the reduction of disasters andoperate in conjunction with disaster reduction activities is available. This is due to the focus ontechnological breakthroughs by satellite image providers which resulted in the lack of enthusiastic
participation of the side actually implementing the disaster reduction activities in this area. It is also dueto the difficulty in using the information extracted from satellite images in actual operations by itself
only-information becomes useful for the first time only with the combination of general geographicalinformation such as topography and natural conditions, and social information such as population,
constructions, and infrastructures. In the introduction of the geographical information system (GIS),
which is the platform for analysis by combining these geographical information, high costs and skills
required pose as enormous hurdles in the use of the satellite information for disaster reduction.
At the first ADRC International Meeting, held February 16 to 18, 1999, a workshop entitled “Use ofTechnology” was organized to discuss the use of GIS and remote sensing for disaster reduction. The
following conclusions were reached:• All member countries recognized the value of GIS and remote sensing, and their advantages ininformation management.
• Future tasks include acquiring real-time satellite images, acquiring satellite data at lower costs,
technological support for introducing GIS and remote sensing, and acquiring technologies for
extracting disaster reduction information.
Despite the high interest shown in GIS and remote sensing by the disaster reduction authorities in eachcountry, high costs and the necessary skills pose as obstacles in the application of these technologies.
Also pointed out were the high costs required for the use of satellite and geographical data.
In order to resolve these problems, the ADRC developed VENTEN (Vehicle through Electric Networkof disasTer gEographical informatioN), a disaster reduction Internet geographical information system
which can be accessed by anyone, anywhere, using the rapidly growing Internet.
The goals in the development of VENTEN
were to provide both a system and data.
This system can be used with a PC
connected to the Internet and a World
Wide Web browser.
Various international organizations, etc.
provide basic geographical informationsuch as topography and natural conditions.
In order to browse and understand thisinformation, it is necessary to convert thedata format according to the GIS used.
Thus in developing VENTEN, various
geographical information was gathered
and converted to a format which can beused immediately on the VENTEN system,and provided with the system.
Fig. 3-7-1-1 shows the positioning ofVENTEN. On the left, are thedevelopment and research organizations
and organizations providing informationsuch as aviation photograph information

Fig. 3-7-1-1 Pointing of VENTEN

VENTEN System67

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service organizations, which provide the primary Figure 3-7-2-1 Processing Flow of VENTEN
data. In order to extract useful information
for disaster reduction from this primary data,
numerous image processing and adjustments
Web Server
are required, as are the means to send thisUsers
Windows NT IISGIS Server
information to the side handling the actual
RequestInformatix & Cad Corp
SIS on Windows NT
disaster reduction work. Disaster reduction
Microsoft Active
researchers can also browse, analyze
Server Page
Command Request
information, and add results to VENTEN.
The VENTEN system has database andBitmap Image
analysis functions for disaster reduction
remote sensing information, and by serving
DB Serveras the information transmission route tothose working on disaster reduction, it
enables the use of disaster reduction remotesensing information in actual activities, toreduce damage such as the preparing ofFigure 3-7-2-2 VENTEN Main Page
disaster reduction plans and support ofrescue activities.

3-7-2. VENTEN System
VENTEN system consists of the Web server,GIS server and database server. Fig. 3-7-2-1
shows the information processing flow inVENTEN. Upon request from users, theWeb server specifies necessary information
including what geographical data and whatpart of area are needed (more than one
geographical data is possible to be specified),for GIS server. The GIS server, if necessary,referring to the data server, abstracts thenecessary part of area from the geographicaldata accumulated within itself, and thenprocesses it to send to the Web server in aform of a raster image data. The Web serveradds to it country selection menu, disaster
geographical information selection menu,
show/hide selection button for basic
geographical data and button for changing
scale and area to be displayed other thangeographical data. Then it sends users
information in hypertext format including
the raster image data provided by GIS
server.
In the aim to create a system which can beused easily even by first-time users, themain page was sharply revised this year
(Figure 3-7-2-2). NOAA satellite images
were also added. Figure 3-7-2-3 shows theinitial screen of the VENTEN system.

Figure 3-7-3-3 VENTEN System Initial Screen

There are a couple of systems for Internet based GIS. For example, one of them can be used bydownloading an application program. Another system based on an image map only provides
geographical information. VENTEN can be positioned in between those two systems in system wise. In68

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other words, users can process vector data on
Figure 3-7-2-4 Designation of 50 km range
VENTEN, but obtain only raster data based
from Narita Airport as Buffer on VENTEN (Top)on the vector data. Although it restricts users
and Results of Calculation of Population in
to obtain data, this system solves theBuffer Area (Bottom)
problems of difference in response caused bydifferent
network
environments
andperformance of client machine at the time ofoperation, and of property right for data. For
Internet GIS, traffic load of network insending data is problematic. However, since
VENTEN only sends a fixed scale of imageof 470 x 470 pixel to be displayed at centerof VENTEN screen, it take server longer incalculation and difference in network
environment between VENTEN and end
users does not have significant impact in data
sending. Most data processing is done byserver machine and all the client machine
should do is to display data it receives, sothat difference of performance in various
client machines does not have significant
impact. It is easy to persuade many data
providers to join in this system because
vector data which is very close to the original
information in its amount, is not given to users. The users will finally get only raster data, but user canprocess it as if they could process directly vector data.
VENTEN has GIS standard functions of "drawing map in any scale", "buffering", "overlaying" and"searching by location and attribute". Fig. 3-7-2-4 shows a buffer with abstracted results of populationof cities in the buffer. The buffer is set to 50
km with Narita International airport as itscenter. The city names and their population inthat area are displayed as the results as shownin the following.

Another newly developed function is theshortest route analysis function. It determines
the shortest route for evacuation andtransportation of supplies. Specifically, thesource of the supplies is taken as the starting
point S and the stricken area as the destination
E. Among the many routes displayed, theshortest route is displayed in bold lines(Figure 3-7-2-5). This function is not only
useful for searching for the shortest route butalso as an operational function which can beused together with other buffering functionsfor searching for routes to avoid damaged
area
In this way, VENTEN provides raster based
information to the end users, but the users canmake various requests to process vector dataon the server.

3-7-3. Data Provided by VENTEN

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Figure 3-7-2-5
Results of Analysis of Shortest RouteMAP

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VENTEN gathers data for the 23 member countries ofthe ADRC. Two types of information are collected;
basic geographical information whose use is not
restricted to disaster reduction, particularly topography
and natural conditions, and disaster reduction
geographical information on maps. Until now, thefollowing information has been gathered:Figure 3-7-3-1 Map of basic
Geographical Information (Top) andMaps including Satellite Data of
NOAA Vegetation Indices (Bottom)

1) Basic geographical information
National borders (region), water systems (line, region),railroads (line), roads (line), airports (dot), position ofcities (dot), city name (character strings), population(number), shaded image based on sea level (rasterimage), contour drawings of sea level (raster images)(Data source: DCW (Digital Chart of the World), GRID,GTOPO30).
2) Disaster reduction geographical information
Flood areas during the 1998 Chang Jiang flooding,damage to homes around Nishinomiya Station during
the 1995 Great Hanshin-Awaji Earthquake, damage bystreet number of town based on the household damage
survey during the 1995 Great Hanshin-Awaji
Earthquake, active fault distribution drawing.
A menu on basic geographical information is provided
at the bottom right of the VENTEN screen, to enable
the information to be displayed or turned off anytime.
One data improvement made this year was the introduction of NOAA satellite data, which is thevegetation index with 16 km resolution. (two terms, July and December 1998). This offers theadvantage of acquiring covered land maps which are indispensable to disaster measures. In addition,
this introduction plays a large role as a test of the introduction of satellite data such as LANDSAT andSPOT, etc. The ADRC plans to analyze the results of the trial introduction this year and review theintroduction of other satellite data in the future.

3-7-4 . VENTEN Experiments and Future Prospects
In order to run the VENTEN system abroad, the absolute cooperation of the governments and researchorganizations in the concerned country is required. For this reason, we have been conducting a casestudy in Indonesia, one of the developing countries with excellent partnership between therepresentative of this research and the organization belonged to. Indonesia is prone to various natural
disasters such as earthquake, tsunamis, volcanic eruptions, forest fires, landslides, floods, etc., making ita country where effects of joint research sharing data and using information processing can be looked
forward to considerably. Test runs in Indonesia are useful in aiming at a VENTEN system which can beused properly during actual disasters. During the tests runs in Indonesia, tasks no transmission speed
and operatability were mainly organized. The ADRC plans to continue tests on mutual data exchange
between Japan and Indonesia using information technology.
The development of disaster reduction geographical information systems using the Internet has mainly
been explained from the viewpoints of background, system, and data provided. At this point, VENTEN
only has the minimum performance for disclosure. The ADRC hopes to increase data, perform tests indisaster reduction administrations, and based on the results, improve the interface, expand functions,improve engineering software performance, and set up high speed Internet lines. To increase users,
efforts will be made to construct a system which takes users needs into consideration as well as

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implement further PR activities.

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