Based on example,this paper indicates that torque constant k t and back-EMF constant k e are not identical in BLDCM, at least can be said their relationship used to think is inexact.

Based onthe previous works, the longitudinal piezoelectric constant d_(33), electromechanical factor k_(33) of 3m point group crystals LiNbO_3, LiTaO_3 and PZT60/40 were summed up.

Research on piezoeletric ceramic material with high piezoelectric coefficient and high Curie temperature;

The dependence of type and mass fraction of ceramic powder,type of polymer and poling parameters on the piezoelectric coefficient d_(33) of piezoelectric composites was investigated.

By accounting the piezoelectric coefficients the authors got consistent result fr.

In this paper,crystal orientation dependence of piezoelectric constants: d 33 、 d 31 and electromechamical coupling factors: k 33 , k 31 for LiNbO 3 and LiTaO 3 in three dimensional space have been calculated phenomenologically through the coordinate transformation method.

The results of measuring 20 typical high resistances show that most of the high resistance values undulate about 1%, but a few high resistance voltage coefficients are up to 15%.

Based on analyzing the structural characteristic and the concrete parameters of CVT in the piolt project,three methods including difference method,voltage coefficient method are presented.