Effects of degree of vacuum and temperature on properties of ultrasonic motor;

Study on resonance frequency of the longitudinal-torsional ultrasonic motor by prestress;

Coincidence of resonance frequencies for longitudinal and torsional composite type ultrasonic motor;

Piezoelectric ceramic ultrasonic motors and its application;

In this paper, the effect of adhesive on the vibration of the stator in ultrasonic motors was investigated in details.

Effects of direct sound and one time reflection of railway noise on residential quarter were mainly considered, and model for prediction of attenuation of railway noise in residential quarter was given in the paper.

When we use it to test the underwater target strength,one problem is how to discriminate the direct sound of the source with the echo reflected from the target,finding the target character quickly.

The factors,which influence the distribution of the amplitude and phase of the points in the phase interferogram of SAR-ATI moving targets indication,including radar-noise,scatter energy,background uneven RCS and the side lobe of image pixels were analyzed.