it is introduced that how to measure the verticality of the horizontal axis with the vertical axis of theodolite, in that to ensure the instrument to use normally.

The new technology develop for lateral axis roadhead of EBZ series is introduced,in accordance with the develop process of the lateral axis roadhead of EBZ series,made a summary: the lateral axis roadhead of EBZ series would be developed to large power,heavy type,series,intelligent,automatic with high technology.

Study on hydraulic characteristics of transverse vortex behind sill of energy dissipator with step-down floor;

On the basis of analyzing the main factor affecting the accuracy of synchro, the theoretic analyses quadrature flux compensating and the method how to doing are put for- ward.