文摘
High accuracy surface modeling (HASM) has been proved to be a superior method for surface simulation compared to classical interpolation methods. However, the fact that HASM is time consuming combined with its dependence on its driving field restricts its application in large area problems. This research develops a modified HASM which can get rid of the driving field in the surface simulation, and the parallel version of the modified HASM is also proposed with the purpose of improving its computational efficiency. Light detection and ranging (LIDAR) data are used as an optimum constraint to construct digital elevation model (DEM). Tests show that the modified HASM can perform surface simulation successfully without the driving field. And it also shows that the simulation accuracy of the modified HASM is almost the same as the old HASM and the classical interpolation methods when the sampling rate is larger than 0.5 %, while the modified HASM shows significantly increased simulation accuracy as the sampling rate decreases. This characteristic indicates that the modified HASM no longer relies on the driving field in the surface simulation. And it also improves the simulation accuracy compared to the old HASM and the classical interpolation methods. Tests of parallel efficiency show that the master–slave mode used in the parallel algorithm obtains a satisfactory result, indicating that the HASM can be applied to surface simulation of large area problems. And it also shows that the modified HASM would have great potential where applied in high-resolution DEM and digital surface model (DSM) construction from LIDAR data. Keywords HASM DEM LIDAR Parallel algorithm Simulation accuracy