Advanced Materials Research Vols. 424-425

Abstract: 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

Abstract: The velocity fields of turbulent flow in Tee junctions have been calculated using large-eddy simulations model for three cases of various inlet velocities with periodic porous media. The ratio of the inlet velocity of the main tube to that of the branch tube were respectively 0.5, 1 and 2 in three cases. In the porous medium region of the Tee junction, the velocity at the center is obvious larger than that at the top or the bottom and the pressure drop heightens rapidly. Comparison of the three cases, the pressure drop, mean velocity, normalized velocity fluctuation and the velocity oscillation versus time are increase as the inlet velocity of the main tube increase.

Abstract: During the course of industry control, pure hysteresis, time-varying，non- linear complex systems often occur. It is ineffective to solve the issues above with the traditional fuzzy control and PID control methods. Against the pure hysteresis, time-varying, non- linear characteristics of Aircraft Deicing Fluid rapid heating system, on the basis of Smith Predictor and traditional PID, a Fuzzy-PID control method is proposed based on an adaptive Smith predictor. In this way, pure hysteresis of the system will be compensated, to reduce the overshoot and enhance the stability of the system. By establishing the mathematical model of Aircraft Deicing Fluid rapid heating system and simulating for the model obtain the simulation results, which have shown that the method is effective, can improve the qualities of control and enhance the stability of temperature control system significantly

Abstract: Correction Technology on active power factor is now widely used in AC-DC power supply circuit to eliminate harmonic of power system, to improve the power factor. Firstly the method of power factor correction technology is set out. Secondly, the basic principle of active power factor correction technology is analyzed, then the control method for active power factor correction technology is given. Finally the development trend of active power factor correction technology is analyzed.

Abstract: The problem of energy saving and environment protection has become more and more crucial in China. New promising technology that makes the problem solved is reviewed in this paper, including electric automobiles and electric vehicle charging systems. It is given the group of customers and charging mode of electric automobiles in China. It is suggested the matches between charging modes and vehicle types. In the short term, conventional gasoline or diesel vehicles is the most realistic and effective, while in the long run, China will meet the urgent challenges of energy crisis and greenhouse gas reduction. It needs technology breakthroughs in battery, public awareness and government input to the development of electric automobiles.

Abstract: SrTiO3 nanoparticles were successfully synthesized by a sonochemical method at room temperature. The as-prepared powders were characterized by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM), and exhibited a pure phase SrTiO3 with a perovskite structure about 20nm in size with uniform and nearly spherical shape. It is found that the size of the obtained nanoparticles increased with prolonging the ultrasonic time.

Abstract: The thermal and hydraulic performances of working fluid in three corrugated channels have been investigated, numerically by a three-dimensional model with a new-type corrugation Plate Heat Exchanger (PHE)—double chevron-type PHE (DCPHE). The heat transfer character, the flow resistance and the Performance Evaluation Criteria (PEC) of the working fluid in double chevron-type PHE have been discussed; Results showed that the double chevron-type PHE with 2:1 of corrugation ratio was better one

Abstract: Based on the field testing and analysis of the Tibetan dwelling in Deqin area , and more specifically, the indoor temperature of Tibetan-style dwellings with rammed earth walls as well as the surface temperature of building envelope were tested and comparatively analyzed. The test results show the current situations and features of indoor temperature changes of Tibetan-style dwellings of earth materials, the heat-insulation performance and heat stability of rammed earth wall, which may provide a basis for improving the thermal environment of Tibetan-style dwellings.

Abstract: Aiming at the furnace control system present situation of complex working conditions are not easy to be understood, this paper hearth negative pressure control system for detailed analysis; Combining the identification system known model and combining with matlab for stability analysis; Set in simulink negative pressure system control model. Choose PI and dynamic feed-forward control method to realize control and realize the dynamic interference effectively suppress, attain better control effect

Abstract: At present, water shortage in agriculture becomes more and more serious. This situation makes it necessary to develop precision irrigation, which needs to obtain the accurate crop water stress in advance. However, this signal is too weak to be detected easily. Wavelet analysis has been widely used in the signal processing area for almost two decades due to its excellent time-frequency analysis ability. Therefore, the wavelet decomposition and reconstruction technique is applied to reduce the noises of experimental data collected from corn plants in a farmland. Finally, data analysis results show that wavelet denoising is effective to achieve the weak signal extraction.