关键词: 高精度曲面建模（HASM）, 优化控制, 不规则三角网（TIN）, 回放等高线, 高程分布频率

Abstract: The HASMOC（High Accuracy Surface Modeling-Optimal Control） method is based on HASM, on which more constraint equations are added. The latter is mainly used to reconstruct surface from discrete points, while the former can be also used to reconstruct terrain surface from contours. By minimizing the norm of the combining equation of the two basic equations of the HASM method, subject to the equality constraints from sample points and bound constraints for each grid points which are surrounded by contours, HASMOC method can preserve the smoothness of the terrain surface, and the high fidelity to the original contours. A real contour lines example is given, and results from HASMOC are compared with that from TIN（Triangulated Irregular Network） method, as for the respects of retrieved contour, details of surface and histogram of surface height distribution, the former is superior to the latter in terrain surface reconstruction from real contour lines.

Key words: High Accuracy Surface Modeling（HASM）, optimal control, Triangulated Irregular Network（TIN）, retrieved contours, histogram of height distribution