DEVELOPMENT OF OPEN SOURCE SOFTWARE FOR MULTI-TEMPORAL DISASTER MONITORING ACROSS NETWORK WITH DYNAMIC DATA EXCHANGE

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1 DEVELOPMENT OF OPEN SOURCE SOFTWARE FOR MULTI-TEMPORAL DISASTER MONITORING ACROSS NETWORK WITH DYNAMIC DATA EXCHANGE Wanapong Kaewsing, Anusorn Rungsripanij, Pisut Naknuenwai, Siam Lawawirojwong, Sitthisak Moukomla, Thudchai Sansena, Kampanat Deeudomchan Geo-Informatics and Space Technology Development Agency (Public Organization) 196 Phahonyothin Road, Chatujak, Bangkok, THAILAND Telephone: (662) Fax: (662) ext wana@gistda.or.th : rnusorn@gistda.or.th : pisut@gistda.or.th : siam@gistda.or.th : sittisak@gistda.or.th : thudchai@gistda.or.th : kampanat@gistda.or.th KEY WORDS: NASA World Wind, Digital Thailand, WMS, Map Server ABSTRACT: The objective of this study is to develop a web-based geo-information service using open source software for distributing Multi-temporal data such as flooded areas satellite imagery and GIS base line data, which will be provided through internet to related agencies. In this study, we used NASA World Wind version 1.4.0, which is an open-source software. We also created a plug-in called Language Switcher for Thai language user-interface, and customized XML files to control data display according to request sent to the server. We used Luster Cluster on Linux OS to provide a data cluster for the server. We configured Apache Web Server and UMN MapServer to provide Web Map Service (WMS), which comprised GIS base line data and disaster data such as map of flooded areas interpreted from RADARSAT and SPOT-5 images, and from LANDSAT-5 acquired in dry season covering the whole country. The tools that we developed can display GIS base line data, multi-temporal disaster data and satellite images on a fully 3D interactive globe through NASA World Wind, and we called it Digital Thailand version INTRODUCTION NASA World Wind uses Microsoft.NET technology for rapid development and to easily access open standards such as XML, WMS, and other graphics standards. Real-time 3D graphics are driven by DirectX allowing a wide base of compatibility with accelerated video hardware. It combines NASA imagery generated from satellites that have produced Blue Marble, Landsat 7, SRTM, MODIS and more. Digital Thailand Project use free and open source software called NASA World Wind and UMN MapServer. The main purpose of this project is to develop Geo-Informatics Network so that relevant agencies can simply make use of geo-informatics available in the network. Information from various providers can be shared and exchanged, regardless of WMS programs they use. 2. OBJECTIVE To develop web-based geo-information visualization system from open source software for Thai community.

2 3. IMPLEMENTATION 3.1 System Architecture The system based on Digital Thailand project was constructed for both client and server side. In the client side, NASA World Wind requests the necessary data from server side across the internet, downloading only the information that is required to display the view requested by the user. In the server side, we created maps for the internet using GIS data such as GIS base line data, multi-temporal disaster data and satellite images by WMS services. Figure 1 shows the system architecture. 3.2 Server Side Architecture Figure 1: Digital Thailand Project Architecture The servers using Luster Cluster on Linux OS were constructed from front-end nodes (Web Server Tier) and back-end nodes (Data Tier). On the front-end nodes, two Ethernet interfaces are required. The interface that Linux maps to must be connected to the same Ethernet network as the back-end nodes. On the back-end nodes, the Ethernet interface that Linux maps to must be connected to the cluster's Ethernet switch. The network of this system is considered private, that is, all traffic on this network is physically separated from the external public network. Figure 2 shows the server system architecture. eth1 eth1 eth1 Apache Apache Apache Figure 2: The Server System Architecture

3 3.3 Client Side Architecture NASA World Wind starts when the user double clicks on the "world wind" icon. The splash screen opens and all redirect files on the client request a new configuration file on the server and replace code of [DigitalThailand14.xml into [DigitalThailand14.tmp. NASA World Wind caches the WMS requested data locally by [DigitalThailand14.tmp. Figure 3 shows the process flow on the client side. Initial (Splash Screen) Read redirect files (.xml) Static Read layers collection Display World Window Dynamic Redirect Request new config files to server [DigitalThailand14.tmp Zoom/Pan Request WMS layers Server [DigitalThailand14.xml GISTDA WMS Services Display Map Response Cache files (.dds) Customizing of XML files Figure 3: The process flow on the client side The data preparation for NASA World Wind was controlled by customizing XML files called [DigitalThailand14.xml. All of WMS services, the positions of places and the administrative description must customize on it. We prepared the positions of places by transform shapefiles to [DigitalThailand14_PlaceMark.xml, using Arcview extension. We prepared administrative description by transforming name to Annotation using Placenamemaker, which is plug-ins of NASA World Wind to PlacenameListFile(.WPL) Plug-in development The original NASA World Wind does not supported Thai language. Therefore we developed software architecture for Thai language support by recompiling the source code. We changed variables on code of sidebar and caption position from private to public, and changed the font type from ANSI to window 874. Figure 4 shows the flow on the client side development.

4 Change the font type from ANSI to window 874 NASA World Wind Plug-in for translate language Thai.xml and any.xml Change variable on code of sidebar and Caption position from private to public WorldWind.exe, WorldWindow.dll and PluginSDK.dll Figure 4: The flow on the client side development 4. RESULTS 4.1 Client Side Results The names and details of place marks around the world, Menu side and Layer Manager side were changed from English language to Thai language (Figure 5) by plug-in called Language Switcher and the other language can be created by XML file. This plug-in can be download at The icons of Toolbar were added by LayerSet.TMP including icons for LANDSAT5-TM Imagery, SPOT5 Imagery, Administrator, School, Hotel, Airport, Tourist Place, and Interesting Place (usually replaced at interval time by LayerSet.XML on the server). Figure 5: Digital Thailand user interfaces The following list of the main datasets currently available in the default installation of Digital Thailand Administrative boundaries (province, amphoe and tumbon.) 2. Roads (main road and sub-road.)

5 3. The positions of places were added on [DigitalThailand14_PlaceMark.xml including schools, hotels, tourist attraction, airports and interesting places. 4. LANDSAT5-TM images with 25 m resolution covering all of Thailand and SPOT5 images with 2.5 m resolution covering 70 percent of Thailand. 5. Data of flooded areas displayed in multi-temporal form (Figure 6). Figure 6: Flooded areas acquired during September November Server Side Results Front-end nodes using the load balancing technique (usually performed by switch) to spread work between three servers and connected via internet The hostname of front-end node(s) is dt.gistda.or.th TileIndex Level 1-n files: Tile index shapefiles for use with Image Pyramid for Matching Concept contains rectangles from extents limits (90.0, 0.0 and 120.0, 30.0) of the Thailand area. Figure 7 shows TileIndex Level 1-n. (90,30) (90,0) (90,120) (120,0) Figure 7: TileIndex Level 1-n

6 4.2.4 Script.ssh: The script files form Shell Script for preparing image files from getmap were run by the authors when the data on the back-end nodes were updated. The following show simple code of Script.ssh. wget -T 60 -O image/ne1_00003_00000.png " &version=1.1&request=getmap&layers=imagery &map=/mnt/lustre/spot5/mapfile/natural2m/tileindex_2.map &width=1024&height=1024&bbox= , , , &format=image/png" 5. CONCLUSION Digital Thailand version 1.4.0, the most recent product from Digital Thailand Project, has proved to be an efficient online mapping application with some GIS capabilities. Currently the Digital Thailand server is on service, serving up-to-date GIS layers and detailed SPOT imagery. The application becomes widely recognized by many governmental offices, private organizations, educational institutions, and general people. The Digital Thailand version software is now downloadable free-of-charge from The application is being continuously developed in order to serve users with more useful vector and raster datasets together with advanced functional capabilities. The server's performance will also be improved in order to provide smooth service to a great number of users in the future. 6. REFERENCE NASA World Wind version 1.4.0, UMN MapServer, Rocks Cluster,