The preventing for a cavity die with a quenching crack by pulse current discharge and lapping repair using spark welding is an effective method to extend its service life and to improve its security and reliability.

The method of lapping repair for quenching crack inside the cold die steel has been studied in this paper in order to prevente the crack.

Objective To analyze the adaptability of home-made gingival retraction cords applied to tooth bodies,gums,periodontiums and prosthetic margins in the state of post-fixed prosthodontic.

In the conventional femoral bypass surgery,the end-to-side 1-way junction is employed at the distal anastomosis,and the blood flow from the graft strongly strikes on the floor of the anastomosis,that results in the violent changes of hemodynamics and leads to restenosis and surgery failure.

At the same time,many fundamental cognitive semantics modes such as experience,activation,projection,prototype,bridging and relevance are applied to the analytic process of coherence.