3. Accumulation and Provision of Information on Natural Disasters and Disaster Reduction

3-5. Internet GIS
3-5-1. Objectives of Internet GIS for Disaster Reduction
Management
The objective of the Geographical Information System (GIS) is to make full use (data input,
analyzing, storing, updating and output) of spatial data beyond the limits of ordinary paper
maps. The term “spatial data” here refers to the data that involves distribution, location,
configuration and attribution of natural topography such as elevation, rivers, human activity
and social situation such as railroads, roads and streets, buildings, land use, vegetation andpopulation. Use of GIS utilities such as visualization by arbitrary overlay of spatial data,
extraction of areas of influence, and selection of the shortest path facilitates users to makedecisions and to assess the influence of the environment and disasters. Development of a GIS
normally requires the introduction of software and hardware, however an advantage of GIS
constructed on the Internet is that a system that allows analyzing, displaying, and acquiring data
through the Internet can be developed without having to install any special GIS software on theusers side. This is very important in handling disaster information as it leads to suppressed
investment on equipment and promote information sharing easily.
In recent years, the uneven spreading of the Internet has caused a problem called "digital
divide". The member countries of ADRC show varying degrees of Internet availability andactivity. However, recent development for faster communication at a lower cost enables moreregions and countries to use the satellite communication technology to access the Internet, we
expect for the Internet GIS as a disaster risk management system in an emergency more eagerly
than ever.

3-5-2. Development of "VENTEN (Vehicle through Electronic
Network of disasTer gEographical informatioN)"
3-5-2-1. Background of development of "VENTEN"
The improved reliability (accuracy and resolution) of information extracted from satellite
images with the progress of image processing technology in recent years enables us to extract
various kinds of information via remote sensing anytime and anyplace and also to apply the
information to disaster management. At this point, no available system can be linked directly tothe reduction of disasters and operate in conjunction with disaster management activities. Thisis due to the focus on technological breakthroughs by satellite imaging providers, which
resulted in the lack of enthusiastic participation by those who are involved in the actual disastermanagement activities in this area. It is also due to the difficulty in using the information. Only
extracting from satellite images is not enough. The information is not useful unless it related togeneral geographical information such as topography and natural conditions, social informationsuch as population, structures, and infrastructures. With the introduction of the geographicalinformation system (GIS), which is the platform for analysis by overlaying this geographicalinformation, high costs and skill are required and poses enormous hurdles in the ability to use
satellite information for disaster reduction.
At the first ADRC International Meeting, held February 16 to 18, 1999, a workshop entitled“Utilization of Technologies” was organized to discuss the use of GIS and remote sensing fordisaster reduction. The following conclusions were reached:□ Conclusion 1: All member countries recognized the value of GIS and remote sensing, andthe advantages in information management.
□ Conclusion 2: Future issues are to acquire real-time satellite images, satellite data at lower
costs, technological support for introducing GIS and remote sensing, and technologies for
extracting disaster reduction information.
Despite the high interest shown in GIS and remote sensing by the disaster management
departments in each country, high costs and the necessary skills pose obstacles in theapplication.
In order to resolve these problems, the ADRC developed VENTEN (Vehicle throughElectronic Network of disasTer gEographical informatioN), an Internet Geographical７２

3. Accumulation and Provision of Information on Natural Disasters and Disaster Reduction

Information System for disaster reduction that can be accessed by anyone, anywhere, using the
rapidly expanding Internet.
The basic framework of this system was developed as part of the project called “Researchand Development of the Disaster Information Network System in Asian Region” funded by theJapan Science and Technology Corporation (September 1998 – September 2001).

3-5-2-2. Overview of “Research and Development of the Disaster
Information Network System in Asian Region”
Awarded funding from the Japan Science and Technology Corporation (segment:
environment and safety) , ADRC conducted a 3-year project - “Research and Development of
the Disaster Information Network System in Asian Region” - from September 1998 to
September 2001. The “VENTEN” (Vehicle through Electronic Network of disasTer
gEographical informatioN) is the internet-based disaster information GIS developed as part ofthe project.
The two main achievements of the project include:□ Development of VENTEN – an internet GIS platform on Disaster Management
Information, and□ Development of the database on disaster management information
The issues that require further development include:□ Enhancement of the database□ Development of satellite communication technology□ Real time communication of disaster information
Study papers on this project have been formulated into the “Research and Development of
the Disaster Information Network System in Asian Region – VENTEN System Final Report”(ISBN 4-901614-01-0).

3-5-2-3. Goal of the development of "VENTEN"
The goal of the development of VENTEN is to provide both a system and the data (including
the results of analysis). This system can be used with a computer connected to the Internet andequipped with a WWW browser.
Although various organizations were already providing, free or at cost, not only basic
geographic data such as topography and natural environment but also GIS data, to view andanalyze the data, it was necessary to convert the format to a compatible one with the GIS
software in use. To resolve the problem, VENTEN is developed with various GIS data
converted into the VENTEN format. The GIS data are managed as part of the system.
Fig. 3-5-2-1 shows the overview
of VENTEN. Data (such as aerial
photograph information) provided
by various space development
agencies, research institutes andorganizations are the original
primary data (on the left). In order
to extract useful information fordisaster management from theseprimary data, image processing
and overlay of data are required in
VENTEN. The results of the above
operation are sent to end-users.
Researchers can also browse,
analyze information, and add theirresults
to
VENTEN.
The
VENTEN system has a databaseand analysis utilities for remotesensing data of disaster and serves

VENTEN System

Fig. 3-5-2-1

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Placement of VENTEN

3. Accumulation and Provision of Information on Natural Disasters and Disaster Reduction

persons in charge of disaster management as an information tool. This enables it to make fulluse of remote sensing data of disaster management in evaluating vulnerability, the preparationof disaster reduction plans and the support of search and rescue, or early warning activities.

3-5-2-4. Overview of "VENTEN"
1) Structure
VENTEN system consists of the
Web Server
Users
Web server, GIS server and database
GIS Server
Requestserver. Fig. 3-5-2-2 shows theinformation processing flow in
VENTEN. First of all the request fromusers are accepted by the Web server.
The Web server specifies the necessary
information including what kind of
DB Server
geographical data and the extent of area
(possible
tospecify
multiple
geographical data) to the GIS server.
Fig. 3-5-2-2 Process flow of VENTEN
The GIS server, referring to the dataserver if necessary, extracts the subject
from the geographical data and thenuploads the data to the Web server in aform of a raster data (image data). The
Web server arranges a country
selection menu, disaster information
selection menu, show/hide selection
button, scale and area management
button to be displayed besides thegeographical data. Then it sends users ahypertext file including the raster
image data provided by the GIS server.
The system is built with an aim thateven first-time users can use it easily.
Fig. 3-5-2-3 Top Page of VENTEN
Jumping from the main page to theonline manual, tutorials and database
are available (Fig. 3-5-2-3). Visualized
information of the vegetation index(NDVI:
Normalized
Difference
Vegetation Index) and land elevation
are also displayed. Fig. 3-5-2-4 shows
the home page of the VENTEN system.
There are several type of Internet
GIS. One of them can be used bydownloadingsomeapplication
programs. Another system based on theimage maps is used as just a viewer ofgeographical information. The method
adopted by VENTEN can be positioned
between those two systems in terms offunctions. In other words, users can
Fig. 3-5-2-4 Start Page of VENTEN
handle the vector data on VENTEN,
but obtain only the raster data based on
the vector data. Although it restricts users to obtain data, this system solves the problems ofdifference in responses caused by different network environments of the client machines at thetime of operation, and of copyright for the data. For Internet GIS, traffic load on the network
sending data is problematic. However, since this system only sends fixed scale images of 470 x
470 pixels to be displayed at the center of the VENTEN screen, calculation on the server-side
takes a longer time. The differences in network environment between VENTEN and end-users
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3. Accumulation and Provision of Information on Natural Disasters and Disaster Reduction

do not have a heavy load when sending data. A server does most data processing and all that theclient should do is display the data received. It is also easy to persuade data providers to join inthis system because vector data, which are very close to the original information, in amount, are
not given to users. The users will get only the raster data, which have been processed using theoriginal vector data.

2) Functions
VENTEN has GIS standard functions of"drawing a map in any scale", "buffering","overlaying" and "searching by location andattribute". Fig. 3-5-2-5 shows a buffer areawith extracted results of population of cities
in the area. The buffer is set to 50 km with
Narita International Airport in Japan as its
center. The city names and their population inthat area are displayed as below. The shortest
route analysis function helps determine theshortest route for evacuation or transportationof supplies. To put it concretely, the source ofthe supplies is taken as the starting point S
and the damaged area as the destination E.
Among the many routes displayed, theshortest route is selected with bold line
(Figure 3-5-2-6). This function is not only
useful for searching the shortest route but also
for searching routes to avoid a damaged areaby combination with the buffering function.
As described above, VENTEN provides
the raster data (image data) to the end-users,
but the users can make various requests toprocess the vector data on the server.
Fig. 3-5-2-5 Designation of a 50 km
range from Narita Airport as Buffer on
VENTEN (top) and Results of the
Calculation of Population in the Buffer
Area (bottom)

Fig. 3-5-2-6 Result of the Shortest RouteAnalysis

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3. Accumulation and Provision of Information on Natural Disasters and Disaster Reduction

3) Data
VENTEN gathers data for the member
countries of ADRC (24 countries as of the endof March, 2003). Collecting two types of
information; one is the basic geographicalinformation (e.g. topography and natural
conditions), the other is geographicalinformation for disaster management. In 2002,
basic geographical information of Asian region
including not only member countries but other
Asian countries has been also integrated into
VENTEN, thus eliminating the blank of basic
geographical information of natural disasters
occurring at the border areas between countries(see Fig. 3-5-2-7).
① Basic geographical information
A menu box is provided at the lower rightsection of the VENTEN screen to choose Show
or Hide basic geographical data.
Fig. 3-5-2-8 and tables 3-5-2-1 and 3-5-2-2
indicate the basic geographical data integrated
into the system to date.

Fig. 3-5-2-7 Map of basic Geographical
Information (top) and Maps including
Satellite Data of NOAA Vegetation
Indices (bottom)

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3. Accumulation and Provision of Information on Natural Disasters and Disaster Reduction

Fig. 3-5-2-8

Basic geographical data integrated into VENTEN (dark area)

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3. Accumulation and Provision of Information on Natural Disasters and Disaster Reduction

Table 3-5-2-1

Basic geographical data

File name(vector data)

Description

Data structure

AEPOINT

Airports

Point

CLPOINT

Cultural facilities

Point

DNAREA

Rivers（polygon）

PolygonDNLINERivers (line)Line

LCAREA

Land coverage

Polygon

POAREA

Seashore lines

PolygonPPPOINTCity names

Point

RDLINE

Roads and streetsLine

RRLINE

Railroads

Line

TSLINE

Transportation facilities (line)Line

TSPOINT

Transportation facilities (point)

Point

Table. 3-5-2-2

Image file name

Basic geographical data

(image data)

Description
Shadow image data

Relief(Changed according to the scale)

DEM

Elevation image data

Vegetation July, 1998

Vegetation index image data (Summer)

Vegetation Dec., 1998

Vegetation index image data (Winter)

Data structure
Raster(approx.10km
resolution)
Raster(approx.1km
resolution)
Raster(approx.10km
resolution)
Raster(approx.15km
resolution)
Raster(approx.15km
resolution)② Geographical data for disaster management□ Damages to housing around Nishinomiya station by the Great Hanshin-Awaji Earthquake
in 1995□ Damages to housing in each district of the city analyzed on the basis of survey results of theGreat Hanshin-Awaji Earthquake in 1995 (by Building Research Institute, Ministry ofConstruction, Japan)□ Flood in Chang Jiang in 1998
□ Distribution of active faults (Japan, Eastern area of Nepal, and Sakhalin (Russia))

3-5-2-5. Future development plan of "VENTEN"
1) Basic geographical information
The scale of geographical data currently integrated into VENTEN is mainly 1:1,000,000.
On the other hand, the scales most frequently used for the basic national land maps are
1:50,000～25,000, and maps at scales of 1:5,000～2,500 would be desired for city planning

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3. Accumulation and Provision of Information on Natural Disasters and Disaster Reduction

including disaster management planning (disaster preparedness and emergency response).
Today, however, it is impossible to integrate map data of these scales into the VENTEN systembecause such detailed digital map data are not available in many Asian countries. If thedevelopment, updating and distribution of high-resolution GIS data via satellite observation
become possible in near future, the integration of those achievements in the VENTEN system
must be taken into account. ADRC will continue to update geographical data as far as possible.

2) Geographical Information for Disaster Management
Information of active fault distribution in Asian countries is extremely important inearthquake disaster reduction. However, there are many difficulties associated with thecollection and arrangement of actual data due to the severe natural environment or economic
and technical reasons. In collaboration with researchers of active faults in Japan, ADRC iscurrently promoting a data process technology project to reveal the distribution of active faults
exposed on the surface through the stereoscopic vision processing of aerial photographs insome member countries experiencing severe earthquake disasters. This method has anadvantage of revealing the existence of possible active faults without any on-site geologicalinspection. In addition, the survey of topography from a wider view enables detection of active
faults that might be missed by a field survey, not being influenced by local disturbances. We areinvestigating the incorporation of these data into VENTEN.
GIS data should be accumulated not only for earthquakes but also for other natural disasters
such as tidal waves, floods, volcanoes, landslides and droughts. ADRC will take into accountthe integration of databases created by external organizations in accumulating the data.
It is also important to incorporate disaster reduction, damage information, such as hazard
maps, early warning and result of damage as GIS data and make them available on VENTEN.
Various maps are available today, but useable GIS data are still limited. ADRC plans to include
hazard map information in VENTEN.
3) Linkage with satellite data suppliers
ADRC is currently conducting researches on construction of a disaster information network
utilizing high-speed Internet satellite (WINDS:Wideband InterNetworking engineering test and
Demonstration Satellite), remote sensing and mobile technology under cooperation with the
National Space Development Agency of Japan (NASDA), the Communications ResearchLaboratory (CRL) and Diamond Air Service Inc. (DAS). The purpose of this project is toenable real time transmission of image data from high resolution camera equipped on an
aircraft to the headquarters when a severe disaster occurs. If information is made available on
ADRC’s website, it contributes to the prompt sharing of disaster information and to theemergency response activities.
In addition, it can be used as a real-time examination of images shot by the crew on site toassess damage. This system must be linked with GIS, and how to incorporate the technology
into VENTEN requires further researches.
The launch of WINDS is planned for 2005. Another subject of research is the method for
VENTEN to use data from the Advanced Land Observing Satellite（ALOS）that is planned forlaunch in 2004. A contribution to the Global Map project is one of the aims of ALOS, andsuccess of ALOS will sure be a great help in sharing high-resolution geographical data at the
global level.
4) User interface and function improvements
Some parts of the current version of VENTEN are yet to be improved to provide moresophisticated user-interface. Help information, user manuals and tutorials must be improved. It
is also necessary to identify the needs of end-users through questionnaires and workshops.

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