This paper briefly introducs the definition of DEM and the present methods of DEM modeling at first,at last, exploits a method of high quality DEM modeling by digitized contour and analyses the feasibility of the method.

Study on processing technology and quality control low sugar yoghurt-beer drink;

Anti-corrosion coating quality control of the concrete structure in tideland;

Study of preparation and quality control of Shugan Xiaozh Granules;

The essentials of quality controlling for the concrete injection stakes on bridge beams;

Construction technique of concrete with nonsticking-combined prestress for after-tensile method and its quality controlling;

Functional test of secondary-ash debris and quality controlling methods;