Using the self-made XMH-160 linear friction welder,the influence of friction time on friction deforming of TC4 alloy was studied in linear friction welding.

The inter-batch optical erasure time constant, τ F, is theoretically introduced, to evaluate the optical erasure to electronic gratings compensated by ions.

This paper enumerates the most possible causes of short-circuit faults on 10kV bus in transformer substation,discusses the hazards of the short-circuit current on 10kV bus to switch cabinet and main transformer,the necessity and three methods to shorten the clearing time of fault are put forward.

An experimental investigation of the influence of the expansion device of the defrost time of an airsource heat pump chiller during the reversecycle defrost is presented.