Parallel Watershed Analysis Of The Grid DEM Based On The Multi-core Compter

Watershed analysis technology is to scientifically classify and process information such as the terrain elevation data collected by digital ways, is to simulate surface watershed analysis under the operation of the computer, is an effective method to encourage people to understand the geographical and predict the terrain change.Parallel computing technology which takes particular program design and data processing to improve the efficiency of dealing with problems is a form of computing comparatively serial computing technology. With the development of science and technology and the popularity of home computers and applications, multi-core hardware configuration of the computer is becoming more and more common. The fully use of computer hardware resources has very profound significance and research value as the try of human to develop our existing brain cells.This paper analyzes the use of a large number of grid DEM data in watershed analysis and the application of high resolution grid DEM data in watershed calculation. The various steps of watershed analysis were researched carefully. The watershed analysis algorithm was summarized. Ideas about parallel watershed analysis were put forward due to the key technology of serial watershed analysis. Design program tries to realize parallel watershed algorithm under the DEM data and achieve a watershed analysis on multi-core computer, with the help of Open MP technology. The main research results for the following several aspects:(1) The advantages and disadvantages of existing serial watershed analysis algorithm were summarized after thorough analysis of method and the key algorithm that serial algorithm used in digital watershed analysis. In the face of the arrival of the era of big and high precision data, it is extremely urgent to develop parallel algorithm of watershed analysis technology based on the efficiency of serial algorithm analysis.(2) In the study of parallel program algorithm, the present widely studies of parallel framework include Open MP framework and TBB framework that for multi-core parallel shared memory as well as MPI parallel framework which face process in parallel in message passing model. In the design of multi-core computing, applications of grid DEM data parallel are not common. The key point of this study is oriented to the application of multi-threaded parallel Open MP model in digital watershed DEM data analysis and puts forward the design scheme of parallel watershed analysis.(3) Analysis on grid DEM watershed algorithm of main structure and the parallelism conducted in-depth analysis, and presents different algorithms of parallelization strategies and code implementation.(4) In DEM data of ganjiang river basin as an example, analyzing the parallel algorithm was tested, from the experimental results, compared with serial algorithm and parallel analysis efficiency is high, which indicates that the digital watershed multicore environment analysis of the feasibility of the parallel algorithm.