User:Ashisksaha

(Landslide-Safe Intelligent Route Finder)
Dr. R. P. Gupta1 *, Dr. M. K. Arora2, Dr. A. K. Saha1, Mr. M. L. Virdi2

1Department of Earth Sciences, 2Department of Civil Engineering Indian Institute of Technology Roorkee Roorkee – 247 667, India ( * E-mail: rpgesfes@iitr.ernet.in )

Many parts of the world with young mountain chains, such as Alps, Himalayas, Rockies and Andes are highly susceptible to landslides. Due to the general ruggedness and steep slopes, roads provide the only way of transportation and connectivity in such terrains. There is a great need to develop a strategy utilizing advanced techniques of geoinformatics for route planning in such areas. LaSIRF (Landslide-Safe Intelligent Route Finder) is a program specifically developed for the purpose. It utilizes various input data layers, viz., DEM, geological structure, lithology, lineaments, drainage, landuse/landcover, landslide distribution, and landslide hazard zonation. The route planning procedure comprises of four basic steps:

(1) Generating a thematic cost map, where value at each pixel gives the estimated relative cost of passing through the pixel. (2) Selection of connected neighbours, which includes finding various possibilities of connected nodes. (3) Calculation of neighbourhood movement cost, i.e. the cost of moving to the connected neighbour from a source. (4) Selection of least-cost route, which is the final step, based on Dijkstra’s Algorithm.

Technical Highlights:

Uses 7 x 7 moving raster window (rather than usual 3x3). Uses 32 unique neighbourhood options, to allow smooth and gentler alignment. Complies with recommendations for hill roads. Computes directional gradient on pixel-to-pixel basis. Flexibility to adjust factors and costing to suit local requirements. Provides integrated optimisation in terms of thematic cost, gradient and length.

A few examples are given below.