This paper discusses the structure type and design features of GTH resistant ring type silencer with the view of ring type flow passage as the deformation of rectangular one.

Based on the principle of traveling wave ultrasonic motor and the results of the Finite Element Method analysis, a new kind of ring type traveling wave ultrasonic motor which is the smallest one in the same type in China has been designed and fabricated.

Short-circuit current calculation for naval alternating current loop power network;

The annular supporting excavations increase with the popularizing of rotundas and sphere buildings.

The problem of finding strongly connected orientations (one way street assignment) for graphs,Specifically,the annular street graphs consisting of n 1 annular streets and n 2 avenues radiating from the center, which arise from annular streets of cities is studied.

The annular swirling jet is an important and unique kind of flow movement form.

However it can t be analysed when the resection point falls on the danger circle and the calculationprecision can t be guaranteed if the resection point falls in the ring area nearby the danger circle Areliability verifcartion method is plesented if the resection point falls on or in the danger circle or thenearby ring area and the related analystic methed is also given.