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In order to solve the contact problem of motional cable and plane, a physical model based on thin elastic rod theoryfor motional cable is proposed.The modelanalyzes the contact problem and formulates the constraint equations by using the Lagrange multiplier. The model is solved by the method of nonlinear constrained optimization. And an example of text is given to prove the feasibility of the model and the solution. The result shows that the model and solution can truly represent the deformation characteristics of the cable under smooth plane constraint.

This paper presents the kinematics for 3-PTT parallel machine tools, the kinematic is analytically performed, the forward and inverse position kinematic equations are explicit functions and workspace is derived and there is no singularity configuration and kinematic coupling in the whole workspace. The manipulability analytical of the parallel machine tool is investigated by the Jacobian matrix.

This paper introduces a satellite /3G+ multi-link communication terminal based on medical rescue information system, which provides 3G wireless network and satellite communication services and integrates cellular phone, maritime satellite terminal, BeiDou user device and Iridium phone [1]. The new terminal could improve the communication adaptability and transmission efficiency for the emergency medical rescue information system even in hostile environmental conditions [2] (such as earthquake, flood, and war). Tests showed that: this terminal has the advantages of simple access, rapid switch, efficient transmission, it can also guarantee timely and effective interaction of all kinds of information, so as to ensure the time-effect treatment for emergency medical rescue system [3].

In order to improve the resolution and accuracy of the inversion, this paper proposed a new inversion method. By introducing constraint sparse spike inversion, the new method can fully take the advantages of high vertical resolution of logging data and the preferable transverse continuity of the seismic data to improve the resolution of the profiles and the quality of imaging and inversion in specific areas. Experimental results showed that this solution can deduce more precise and reasonable inversion result than other inversion solution. Constraint sparse spike inversion can generate reflection coefficients with broad frequency band and solve the marking problems preferably, thereby makes the impedance model obtained from the inversion even close to the actual situation underground.

This study is focused on the locomotive of high speed train. First, wind tunnel test is used to verify the credibility of numerical results. Then, in order to compare the difference of aerodynamic noise generated by different size locomotive, dimensionally similar models of 1/8th, 1/12th and 1/15th scale are studied by using numerical simulation, including stationary aerodynamic characteristics, fluctuation characteristics of unsteady flow, noise source distribution on surface and far-field noise spectral characteristics. Based on the result of pressure fluctuation, it is noted that the difference between 1/15th and 1/8th scale model is larger in individual parts, including the separation zone in the roof and the edge of window. In addition, according to the far-field noise calculation, the result of 1/12th scale model is better than 1/15th scale model. From the results mentioned above, 1/15th or much smaller scale model should not be used in wind tunnel test as possible.

Based on the open-jet aero-acoustic wind tunnel, an experimental study was made to research the effects of the jet-flow on sound propagation. This study is focused on the changes of the direction of the sound propagation, the changes of the sound pressure level, the phenomenon of tone broadening and the availability of the existing prediction method for sound propagation in jet-flow. The results indicate that the influence of the jet-flow on the value of the noise source shift varies along the direction of the jet-flow and there is no regular influence on the sound pressure level. In addition, the flow around the test sample has affected the sound propagation, and the phenomenon of tone broadening exists when high frequency signal is used. The study also reveals the limitation of the application of the existing prediction method, because the model it used is too simple.

Transmission influences on the performance and the security of tilt-rotor directly. A transmission-wing coupling dynamic model including time-varying mesh stiffness and static transmission error was proposed, then calculated the dynamic loads of the transmission-wing coupling system under two flight modes: aircraft and helicopter. Then, computed the life of transmission under different system reliability based on the dynamic loads. This paper presents a more accurate transmission life estimation method. The results present some useful informations for dynamic optimization of the transmission and provide a theoretical basis for the transmission design.

According to the micro-climate environment outdoor of the region, wind environment outdoor which is under planning programming can be done analog computation using computational fluid mechanics PHOENICS software. A set of comprehensive prediction and assessment system which is mainly focused on outdoor environment composite index WBGT can be established combining with assessment method on wind environment outdoor of predecessors in order to more accurately and humanly predict and assess the wind environment outdoor, bring safe, comfortable and healthy outdoor environment and provide references for the assessment and design of green residential district.

A 3-DOF in-parallel machine tools based on a tripod mechanism is developed and studied, the kinematic is analytically performed, the workspace is derived, Analysis of the a number of conditions of the Jacobian matrix and manipulability is carried, The manipulability analytical of the parallel machine tool is investigated