Important problems about the hierarchical defending of important area in post-emergency voltage control are studied.

In order to understand the bearing time, growth character, the over-ground biomass and nutrition content and layering distribution, prevention of seeds pest, a study on Vicia amoena of Korean Autonomous Prefecture of Yanbian was carried out.

Technolo-gy of separated-zone sand control & water injec-tion in the sanding oil reservoirs,Chengdao Oil-field,Shengli;

Exploration of Layer Defence of Anti-ship Missile;