supported by Joint Funds of the National Natural Science Foundation of China(No.11176023);National Natural Science Foundation of China(No.51306135);partially supported by the China Postdoctoral Science Foundation(No.2013M532040);Special Financial Grant of China Postdoctoral Science Foundation(No.2014T70917)
An increase of the cooling capacities in the liquid helium temperature area is re- quired by Experimental Advanced Superconducting Tokamak (EAST) due to the extension of its subsystems in the near future. Limited by...