On the basis of quadrature theory and dynamic characteristics, the amplitude detection and control theory for HRG (hemispherical resonator gyro) is studied in this paper.

With electromagnetic theory of light, We found that the polarization of the light kept the same when the reflection of incident light satisfied critical reflection or dual-quadrature reflection.

According to the engineering theory of plastic bending, the elastoplastic bending analysis of a beam is conducted using differential quadrature method.