Applied Mechanics and Materials Vols. 530-531

Abstract: Wind energy is the worlds fastest growing renewable energy source in recent years, and it has drawn worldwide attention. Due to high efficiency, simple topology and stable operation, variable speed constant frequency (VSCF) direct-drive wind power generation system using permanent magnet synchronous generator (PMSG) is the development trend and one of the focuses of wind power generation system research. The paper introduces the trend of the development wind power generation and the recently research stage on the wind power generation. Based on the VSCF power fundamental principle, the dissertation analyzes the strategy of wind turbine simulation. In the development of wind power generating system, the wind turbine emulator becomes more and more important because it can provide controllable wind turbine characteristics. Simplified mathematical model based on the CT-λ curve is constructed, the system structure and emulation method are analyzing. Hardware and software are designed and implemented, and a laboratory set-up is building which based on DC motor. Experimental results show that the wind turbine emulator is as good as expected.

Abstract: We studied the logistics vehicle scheduling.We have used Unified Modeling Language (UML) for modeling and java agent development framework (JADE) to realize the Agent server-side interactive collaboration features and set up multi-Agent scheduling platform,and have also used the hybrid genetic algorithm to optimize the scheduling task. Through testing examples as well as the combination use of MATLAB and Visual C+ +, the vehicle Gantt chart has been generated to inspect the performance of optimization algorithm.

Abstract: The practice of BIM technology in the entire life cycle of East railway station building. BIM technology has many advantages in the visualization, coordination and simulation relative to the traditional two-dimensional design. The paper summarizes the use of BIM technology in the design phase of railway station, and point out the use directions of BIM technology in the next stages of construction and operation.

Abstract: On the basis of the existing potted-seedling transplanting mechanism, a new type of transplanter,a automatic rotary potted seedling transplanter of "Cycloid gear train" was proposed .The trajectory and posture were analyzed while the corn potted seedling was transplanted, the principle and characteristics of the transplanter were demonstrated, the kinematics model was established, and the equation of (anglar) displacement, (anglar ) velocity, and (anglar) acceleration were deduced. Based on above research results, the transplanters computer aided software was developed with Visual Basic6.0, then the structural parameters were calculated which could meet the work requirement . Before the prototype is designed, the feasibility of the structure can be proved through the test of the software, and then the final data would be got: α₁=334°, α₂=0°, α₃=66°, α₄=-40°,α₅=90°,α₆=110°,l₁=106mm,l₂=187mm.Two-dimensional and three-dimensional drawings were drawn according to above data; the designed model was simulated by ADAMS, the trajectory and posture that meet the work requirements were verified, too.

Abstract: High-speed aircraft is in service condition of high temperature, high pressure and strong noise during flight. Strong noise will damage structures and equipments of an aircraft, and the existence of high temperature and high pressure will greatly increase the damage degree. Therefore, research on aircraft structure characteristic and surface acoustic characteristic is very significant. The hybrid method of CFD and acoustic solver combination method can accurately obtain aerodynamic noise load on the aircraft structure surface in a high velocity environment. The hybrid method can make acoustic and vibration analysis for aircraft structure, and get influence of noise load on it. The simulated results show that the presence of high temperature and high pressure can make the natural frequency of typical components and whole machine model reduction, and the acoustic load on the aircraft structure model surface is larger at low frequency, smaller at high frequency.

Abstract: Research work on the thermosiphon layout design of transmission line pile foundation in Geermu permafrost region was performed by finite element method and the influence of thermosiphon layout design on the temperature of soil around pile foundation was calculated and analyzed. The numerical calculation results indicated that the cooling effect of thermosiphon was obvious, but the coolling effect varied with the difference of thermosiphon layout design. The more thermosiphon bars were laid out aound pile foundation, the lower the temperature of soil around pile foundation. The cooling effect of thermosiphon on pile foundation and soil became weaker and weaker with the increment of the horizontal distance between soil and thermosiphon-pile. The layout design of 12 thermosiphon bars was the best for the transmission line pile foundation in permafrost region.

Abstract: For a kind of nonlinear system whose input-output function is not differentiable, we proposed a model predictive control scheme based on linearization approximation method. We linearized the object nonlinear system using Stirling's interpolation formula method, and reformulated the control performance index to a quadratic optimization problem, and then, we obtained the optimization control sequences by solving the quadratic optimization problem. In order to reduce the complexity of computation, we ignored the high-order terms associated with the linearization. The simulations show that the presented NMPC scheme can achieve a satisfactory control result, also can decrease the dissipation of control energy and control time.

Abstract: Grain drying with chain coalfired hot blast stove for temperature stable and economic operation.Boiler control objects with strong coupling, large delay, large inertia characteristics.Fuzzy control on object for low, fast response and predict advanced features. Design the fuzzy predictive controller for chain coalfired hot blast stove temperature control.The test results show that the fuzzy predictive control system is improved effectively the static precision and dynamic characteristic.Fuzzy predictive control for large delay system has better practicability.

Abstract: For collectors’ pressure system strong interference, coupled, nonlinear, multi-parameter and other characteristics, based on the inverse system decoupling principle, the reversibility of the mathematical model of the gas collectors’ pressure system is analyzed. BP neural network which has strong nonlinear approximation ability is applied, to approximate inverse system of gas collectors’ pressure system. Neural network inverse system with the original system composes of the pseudo linear decoupling composite system. The neural network inverse decoupling control of gas collectors’ pressure system is implemented. The simulation results show that this method realizes decoupling, has a certain application.

Abstract: A Kalman-PD depth controller was designed for depth system of AUV, and the controller was simulated on MATLAB/ SIMULINK. Performance of the controller was observed with actuator saturation, random pitch sensor noise and random fin disturbances. At the same time, response of a conventional PID controller for depth closed loop was also given for comparison. Results show that the Kalman-PD controller gives well performance in dealing with the noisy and disordered depth control system of AUV.