Natural calamities causing heavy loss to life, crops and structures are referred to as disaster. It is difficult to predict when and to what extent disaster is going to occur. Hence countries and societies take up several methods to monitor, assess and manage a disaster situation. Information and Communication technologies have foremost use at each stage.
This project is about assessment of river flood using Synthetic Aperture Radar (SAR), Grid Computing and Geo synchronous SATellite (GSAT) technology. When a flood occurs an aircraft fitted with a Synthetic Aperture Radar (SAR) is flown over the flood affected region. The SAR is capable of capturing the data about the flood site even in rough weather conditions (cloud, fog, dim light). Typically, if the aircraft flies over the flood region and collects raw data for about half an hour, several snapshots (SAR raw data) are obtained, spanning the length of the river (say 100 – 200km). These SAR raw data sets need to be processed to obtain an understandable image (resultant image) of the region. This requires provisioning of significant compute and storage resources at short notice. This project exemplifies how the high speed network and HPC clusters & storage are useful to solve such a problem in near real time.
The project was conceptualized in 2006 between Centre for Development of Advanced Computing (C-DAC) and Space Application Center (SAC), under the GARUDA grid and the major components were identified. The major components are -
- data acquisition
- raw data transmission & scheduling of data processing
- raw data processing on GARUDA
- back transmission & geospatial visualization of results
DM-SAR (Disaster Management Synthetic Aperture Radar) sensor, fitted on an aircraft, captures the raw data. SAC is incharge of the data acquisition. The raw data thus obtained was sent to GARUDA grid computing resources for processing. C-DAC grid-enabled the program for raw data processing, on the GARUDA grid.
Communication channels between SAC and CDAC include high speed Layer 2/3 MPLS Virtual Private Network at 100Mbps as well as GSAT3 Satellite terminals. Data transmission via both 1 Mbps Satellite links and 100Mbps terrestrial links have been tested and analyzed.
The data transmission and job scheduling required interfacing the Satellite grid (SATGrid) with GARUDA grid. Thus, the SATGrid and GARUDA have been successfully interfaced. GANESH scheduler developed by SAC has been used to schedule the jobs from SAC to GARUDA. Specific interfaces required to connect GARUDA with GANESH have been developed by C-DAC. The data processing job execution / submission has been successfully tested via Satellite and terrestrial links.
Raw data of different resolutions (1m, 5m and 10m) have been processed on GARUDA. The processing time has been compared with that taken on Altix 32-way SMP at SAC. A 9GB raw data processing taking about 6 and half hours on 32 CPU Itanium-2 Altix was observed to reduce to 54 minutes using 272 CPUs of an Intel Xeon cluster.
Specialized geospatial visualization software has been deployed by C-DAC at specific locations using which experts are able to collaborate for decision making.
- Pankaj Ojha, Mangala N, Prahlada Rao B.B, Manavalan R, Tapan Mishra, V.Manavala Ramanujam, Haresh Bhat, Pankaj Ojha, Mangala N, Prahlada Rao B.B, Manavalan R, Tapan Mishra, V.Manavala Ramanujam, Haresh Bhat, "Disaster Management & Assessment System Using Interfaced Satellite and Terrestrial Grids" "Disaster Management & Assessment System Using Interfaced Satellite and Terrestrial Grids", Workshop on Grid and Utility Computing, International Conference on High Performance Computing, December 2008, India
- Pankaj Ojha, Ms. Mangala N ,Dr. Prahlad Rao, R.Manavalan, Dr. Tapan Mishra, V.Manavala Ramanujam, Haresh Bhat, “Grid Enabled Workflow For Management & Disaster Assesment System At Satellite And Terrestrial Grid (GE-MINDA)”, National Conference on Emerging trends in Computing and Communication, December 2008, National Institute of Technology, Hamirpur, India
- V Manavala Ramanujam, Tapan Misra, “DMSAR Processing Software Implementation”, National
Symposium On Advances In Remote Sensing Technology And Applications With Special Emphasis On
Microwave Remote Sensing, Indian Society of Remote Sensing (ISRS), December 18-20, 2008, India
- R.Manavalan, V.Manavala Ramanujam, Tapan Misra, “Garuda Flood Assessment System (G-FAS) “,International Symposium for Research Scholars on Metallurgy, Materials Science and Engineering, December 10-12, 2008, India