The new technology of none-positioner and none-centerpole method assembling large ball-jar was introduced through constructing a 4000m 3 large ball-jar.

Study on no-interlayer diffusion welding technology of Al-Li alloy;

Overview of repeaterless submarine fiber optic cable communication systems;

There are less experiences about OPGW application in UHV,the paper proposed some correlative considerations,summarized main characteristic and the specification of OPGW,brought forward the proposals about optical fiber type selection,control of transmission parameter,structure model selection,repeaterless station and access optical cable,provided the reference for professionals.

The characteristics of personal environments:heterogeneity,short distance between devices,and group mobility,are analyzed,and a decentralized directory storage method is proposed based on them for the autonomous organization of devices.