5LIU J R, JIN B, XIE Y J, et al. Investigation on the characteristics of a new high frequency three-way proportional pressure reducing valve in variable valve system of automobile engine [ J ]. Indian Journal of Engineering and Materials Sciences, 2009,16 ( 1 ) : 7 - 13.
6LIU J R, JIN B, XIE Y J, et al. Research on the electrohydraulic variable valve actuation system based on a three- way proportional reducing valve [ J ]. International Journal of Automotive Technology, 2009,10 (2) : 27 - 36.
7McCLOY D, MARTIN H. Control of Fluid Power Anslysis and Design[ M]. 2nd ed. Ellis Horwood Limited,1980.
