Research on the Shift Strategy for the Traction Vehicle with Automatic Transmission

Firstly, according to the working characteristic diagram of engine and hydraulic torque converter, the matching working point is found. On this basis, the theoretical model of gear shifting law is derived when the engine and the hydraulic torque converter work together by taking the acceleration of adjacent two gears equal as the shift point. Finally, the theoretical model is simulated, the shift pattern diagram of tractor automatic transmission is obtained and the shift pattern diagram is analyzed, and the results are of important reference value for further study of shift delay and other characteristics.

Forecasting Earthquakes by Hybrid Model of Pattern Informatic and PageRank Methods

Although there is no proven method for predicting earthquakes in a short time, it is feasible to evaluate their hazards probabilistically. Here, we aim to find active and passive places of Iran’s geographical region. In this regard, we have analyzed pattern informatic (PI) and the relative intensity methods in Iran as retrospective binary forecasting methods, and used the PageRank (PR) algorithm to rank different places. Then, we introduce a hybrid model of PR and PI methods (PR‐PI) for prediction in the earthquakes network. The results show that our method turns out to be one of the most reliable forecasts compared to other methods based on the common relative operating characteristic diagram. We have also found a regional seismogenic map where earthquakes are likely to occur during a specific time interval in the future.

Study on Nonlinear Backlash of Shipboard Antenna Servo System

Shipboard antenna tracking servo system uses dual-motor technology to overcome the anti-backlash backlash nonlinear transmission system, but when the load torque change quickly or commute, there will be two the motors case through the backlash or one motor at a faster speed bumps tooth surface phenomenon, thereby causing oscillation of the antenna load. Based on the established system model includes aspects of backlash on the system, the amplitude-frequency characteristic analysis, the first, with the increase in the width of the backlash, reduced bandwidth of the system, corresponding to a slower response systems, the more severe the delay, backlash when the end of the second drive, the driven part produced by the collision velocity inconsistent with increasing width of the backlash. the larger of speed control difference of PID becomes, the more serious such a collision. Resulting in the oscillation is possibility, the bandwidth of the system becomes narrow in the amplitude-frequency characteristic diagram.

Theoretical and Experimental Researches Regarding the Performances of a New Type of Rotating Machine with Profiled Rotors

The paper establishes an original computation formula for the flow rate of the fluid transported by a new type of rotating machine with profiled rotors; the theoretical characteristic diagram of the machine - flow rate versus machine speed - is built. The scheme of the test stand used for performing measurements needed in order to build the experimental diagram is presented. The variation of the volumetric efficiency of the working machine in function of the machine speed is finally described.