Study on Updating Method of DEM Based on Large-Scale Topographic Map

Our institude has a digital elevation model that is based on 2008 of ADS40 aerial photography production. DEM is already too old, in the nearly two years of actual use of this data. It have been found that the data is obviously not in line with the actual situation of the elevation. These problems generate direct result that DEM data is difficult to apply in areas which require the application of the three - dimensional GIS data such as urban planning, mobile base station location. So we must generate new updating procedures of Large - scale topographic maps and digital elevation model(DEM).