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Rotary piston engine is a new kind of engine, which is still under development. Based on the kinetic characteristic and the special structure, a valve track was established using high-order polynomial method under the requirement of maximum fullness coefficient. Rotor was fixed after applying a reverse motion on the mechanism. Cam profile was built by coordinate transformation. A 3-dimension model was built and then it was imported into ADAMAS in order to study its kinematics behaviors responding to a specified motion .And the result shows that the method we take is effective; the cam profile has a ideal fullness coefficient, a continual acceleration, no hard or soft impact, and it could easily satisfies the requirement of the design of valve train.

By analyzing the characteristics of the circulating water control system with constant pressure, we established the mathematical model of the system. However, the system with conventional Proportional-Integral-Differential (PID) controller can not achieve excellent dynamic and static performance. An adaptive Fuzzy-PID controller was designed by combining Fuzzy and PID control methods. And we simulated the system in MATLAB/Simulink with the methods of conventional PID and Fuzzy PID respectively. Compared with the method of conventional PID, the results showed that the method we had proposed has the better effect than conventional PID

Taking a group of SPSW with openings with or without edge members as example, this paper states the importance of edge members in view of initial stiffness, ultimate bearing capacity and ductility. First, FEM analysis is carried out to study the reasonable stiffness-range and it is found out when the inertia moments ratio varies from 6 to 8, edge members not only provide adequate anchorage, but also resist loads directly with main frame. Then, an unified calculation model called USMO is proposed, whose key point is to add inversed compression bars with stiffness to tension zone to simulate the increase of ultimate bearing capacity, leaving shearing part same to USM.

Pured ZnO, Al doped ZnO and Al-In co-doped ZnO nanopowders were synthesized by the methanol alcoholysis method at 130 °C. Structure, morphology and optical properties of ZnO nanopowders were characterized using X-ray diffraction, Transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and Photoluminescence (PL) spectra. The results show that ZnO nanopowders can be obtained in methanol solution at low temperature (130 °C). TEM images show that Al doped ZnO nanocrystals grow along the [002] axis quicker than other axes. FTIR spectra show that ZnO nanocrystals synthesized by the methanol alcoholysis include a little organic impurity. PL spectrums reveal that pure ZnO and doped ZnO nanocrystals have a blue band emission at 440 nm and a green band emission at 520 nm and 530 nm, respectively. Compared with the pure ZnO nanocrystal, the Al doping improves the luminescent properties.