Advanced Materials Research Vols. 562-564

Abstract: Medical image reconstruction technique has been an important research topic. Based on cerebrovascular CT image of actual victims, through extracting the contour of image, dividing the nodes and defining boundary, the paper reconstructed 2D grid model of blood vessel of brain. Using the finite element method to simulate and analyze the dynamics features of the medical image mesh model. Through experiment, the paper mainly compared the value of blood velocity and dynamics pressure, and analyzed the difference of hemodynamic parameters in different models. Finally, It found that the model I artery more easily alter form and induce arterial hemorrhage. This will provide the theoretical basis for analyzing the mechanism of Cerebrovascular diseases.

Abstract: In the SIR model once a node is cured after infection it becomes permanently immune,but we assume this immunity to be temporary. So we obtain an epidemic model with time delay on scale-free networks. Using the mean field theory the spreading threshold and the spreading dynamics is analyzed. Theoretical results indicate that the threshold is significantly dependent on the topology of scale-free networks and time delay. Numerical simulations confirmed the theoretical results.

Abstract: A model of CRH2 high-speed train has been established and the aerodynamics process of moving high-speed trains has been numerically simulated by using moving gird technology of CFdesign, Two kinds of operating condition, both trains have uniform and un-uniform velocity, were considered to analyze the aerodynamics pressure on the surfaces of the train. Finally, according to the calculation results, regularity of how the position where the highest pressure wave was located and its peak value change with the velocity increasing is concluded.

Abstract: This paper proposes a method of wavelet transform combined with SVD (Singular Value Extracting), and the abnormal data elimination in its trajectory measurement is studied. After the wavelet decomposition of the observed data, combining the approximate component and the detail component, the phase space is reconstructed. The increment criterion of singular entropy is used for the input observed matrix of SVD, and the singular value is selected. Then the original signal is reconstructed by SVD inverse transform. This method overcomes the distortion problem of data end in phase space reconstruction by Hankel matrix. The reconstructed phase space by components of wavelet decomposition is orthogonal. So it further improves the accuracy of noise reduction and abnormal detection by SVD. The results of experimental data processing show the effectiveness of this method proposed in the paper.

Abstract: For the technical problems that traditional Suction Plug Seedling -Sowing machine high positive hole rate which caused by the highly uneven rate of seeds " boiling ", and put forward the “boiling” way that the tray and seeds are throwing up boiling, innovative design of the thrown system which is compose of mechanical spring ,solenoid and suction cup , through to the theoretical analysis of the process of seeds thrown intrasystem,and established a mathematic model between seeds throw height and structural parameter, based on the SolidWorks software environment to build the multi-body system dynamics thrown model, to simulation and verification law of motion of tray and seeds intrasystem. The testing results show that the throw system can realize the "boiling" condition that seeds could adsorption, ensure that when the planter adsorbed seeds it could take a highly uniform on the thrown height, effectively reduce the positive hole rate, provides a new concept, structure and theory for design and research on the Suction Plug seedling-sowing machine seeds "boiling" system.

Abstract: Because of the great advantages of savings for installation costs and areas of the ground, the ground source heat pump (GSHP) system combined with the ground-coupled heat exchanger with structural member is becoming more and more popular such as energy pile foundation etc.. However, the calculation method especially on the perspective of plate-type ground-coupled heat exchanger (PGHE) has not been established. This paper reports a study on a mathematical model developed to analyze the heat transfer of U-tube plate-type ground-coupled heat exchanger (UPGHE) which combined with structural member and an analytical solution is revealed. The results show that there are clear ‘heat submerge’ for the leg with lower temperature of UPGHE and it is more sensible to arrange one leg apart from another. The results also show that the spacing of pipes have obvious impact on the performance of UPGHE and the temperature difference between two legs have no important effect on the total performance of UPGHE.

Abstract: This paper expounds the structure and working principle of gear-shifting of dual-clutch transmission (DCT), analyzes the shift process of dual-clutch transmission, and establishes its dynamic model and the evaluation index of shifting quality. Aimed at the evaluation index of the impact degree, this paper puts forward the method of controlling oil pressure of clutches and throttle opening of engine which makes the impact degrees to zero, uses smatlab/simulink to establish the simulation and the results tests the method is available.

Abstract: The transport system is a nonlinear, time-varying, lagging large-scale systems. Fuzzy control does not need to build a precise mathematical model, can be easily integrated people's thinking and experience, and is suitable for applications in the traffic signal control system. Here,a self-adaptive optimal algorithm was used to improve the traditional fuzzy controller. Simulation results show that the improved system has higher availability.

Abstract: To achieve the numerical control (NC) system based on the standard for the exchange of product model data-numerical control (STEP-NC), the feature concept and feature recognition method of STEP-NC is proposed. The meaning of feature in STEP-NC, while the three classification methods of STEP-NC feature were also presented. The expression methods of STEP-NC feature were analyzed in details. Furthermore, the feature recognition methods based on above the analyse were described. Finally, we simulate several machining features on STEP-NC milling simulation system. The simulation results demonstrate that the feature recognition method is correct and feasible.

Abstract: The compass satellite navigation system is developed by China which could provide the clock real-time location services, short message service and precision timing services. Based on functions of the compass satellite navigation system, an ATC simulation platform based short message service has been proposed in this paper. The system structure, the functions of the simulation platform and the research content have been presented in detail. Finally the prospects of short message service are put forward to compelling the applications of air traffic management based compass navigation satellite system.