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Based on the background of Dalian subway running through bridge pile foundation, a 3d numerical model is built by the finite element software MIDAS/GTS in order to research the laws of the internal force and the displacement of the pile and soil during the Construction process. The outcome reflects that the sedimentation value of the top of the pile is bigger than others. Because the bigger thrust about the shield machine, the horizontal displacement of the pile is increasing at first and decreasing at last from a positive into a negative. Because of the loss of the soil, the soil beside the pile collapses and causes strong friction force. The surface sedimentation value which is near the central line of the tunnel is bigger than other place. This paper is of good reference roles in the similar underground engineering in Dalian.

Based on the problem of tunnel running through bridge pile foundation, a 3d numerical model is built by the finite element software MIDAS/GTS in order to research the internal force and the displacement of the pile and soil during the Construction process. The sedimentation value of the top of the pile is bigger than others. Because the bigger thrust about the Shield machine, the horizontal displacement of the pile is increasing at first and decreasing at last from a positive into a negative. Because of the loss of the soil, the soil beside the pile collapses and causes strong friction force. The surface sedimentation value which is near the central line of the tunnel is bigger than other place. This paper is of good reference roles in the similar underground engineering in Dalian.

The dynamic viscoelasticity of the outer and inner part of bamboo with different ages was investigated using Dynamic Mechanical Thermal Analyzer (DMA). The results showed that,storage modulus (E’) and loss modulus (E’’) of both outer and inner part of bamboo were increased at temperature between 25-250°Cas the bamboo ages increasing. In addition, E’ and E’’ of the outer part of bamboo were higher of the inner part with the same bamboo age. Also a significant loss peak in E’’~T curves between 190-210°C was found. The peak values of E’’~ T curves of the outer part only shown slight variation with bamboo age increasing. However, significantly different of peak values was found in the inner part. This was caused by the difference of the chemical composition in outer and inner part of bamboo with different ages. The width of E’’ peak varied slightly in outer bamboo of different ages, but in the inner part , it was increased as the age increasing. This revealed that in the outer part of different ages, the chemical composition of the molecular values was closer, In the inner bamboo, it was increased as the age increasing..

Using mechanism design and dynamic analysis software, the simulation is conducted about grasping operation and moving objects for multi redundant manipulator on the basis of mechanism design and theoretical research, as well as the snake crawling motion simulation. The simulation results validate the correctness of theory analysis. The each joint driving torque data and curve provided the effective data basis for the design and development of a prototype.

In this paper, the behavior of composite stub columns under different loading conditions is studied using the finite element method. The accuracy of the theoretical method is validated by comparing with the experimental results. The behavior of specimen under different loading conditions is analyzed. Then, based on the finite element method, the comparison of mechanical behavior under three typical loading conditions is studied. The results show that the difference on bearing capacity will become larger with the increase of steel area to concrete area ratio. For the core concrete loaded specimen with lower steel area-to-concrete area ratio, whose bearing capacity is the lowest, but its ductility is very good. With the increase of the steel yield strength, the bearing capacity will increase evidently for specimen loaded simultaneously. While for the specimen with only core concrete loaded, the steel yield strength has little influence except increase of ductility.

This paper discusses the pole placement with low-order controllers, e.g., PID type controllers and phase lead/lag compensators, using parameter space approach. The damping ratio sector region and the relative stability region in s-plane, which form a trapezoid region in the left-half of s-plane, are mapped into the controller parameters space. Thus, the corresponding controller parameters can place all the closed-loop poles in a specified trapezoid region, and guarantee the performances of the closed-loop systems. The advantage of the proposed method is that it is simple and can be applied to time-delay systems. A simulation example is given to illustrate the effectiveness of the design.

Dynamic mechanical properties of radial curtain plybamboo and its constitution unit-radial bamboo strip were studied using dynamic mechanical analysis (DMA). The results showed: experimental temperature had great effect on dynamic mechanical properties, the shape and alignment of radial bamboo strips were closely related the dynamic mechanical properties of radial curtain plybamboo.

The acoustic performance of sound-isolating and decoupled tiles is studied from macroscopic and microscopic. First, the sound absorption and reverse sound insulation performance of sound-isolating and decoupled tiles is studied based on laminated media; then the acoustic decoupling materials influence on acoustic radiation of double cylindrical shell underwater is studied, using a double-layer cylindrical structure of large-scale as experimental model .There are large amount of operating modes designed in this experiment, such as all laying, partial laying, laying and so on. The results show that sound-isolating and decoupled tiles not only have the effect of weakening the absorption of reflections, but also have reverse sound insulation effect, which increases as frequency increases; for single point mechanical vibration, the tiles can effectively inhibit vibration and sound radiation of high frequency in the double shell.

This paper discusses the parameters tuning of fractional-order controller satisfying the desired gain-margin and phase-margin specifications in terms of a stability equation method applicable to fractional-delay systems. The tuning procedure is then applied to the level control of double water tank, which is modeled as a second-order transfer function with time-delay. The Matlab simulations and the experiments on the water tank device show the effectiveness of the tuning and the benefits of using fractional-order controllers.

It is necessary and valuable to build the transferring relationship between test bed datum and ship datum for satisfying the boundary requirements of exciting forces in ship’s vibration-acoustic analysis. Principle of the force transferring technique for machineries with multiple supporting points is introduced first, and then the measurement method for free velocities of machineries is given. A method for transferring test bed datum to ship datum of machinery force characteristics is discussed and applied to deal with a practical problem, in which the numerical simulation is used for predicting admittance of ship mounting seat absenting reality. Experimental results show that the proposed method is valid.

Finite cylindrical shells with stiffened ribs are major structure of cabin on the submerged or underwater vehicles. This paper aims to probe into the feasibility of sound radiation simulation of underwater structure based on ABAQUS. ABAQUS is used to compute and analysis the underwater sound radiation rule of double cylindrical shell structure. And the computation data agrees with the experimental data basically. Adopting boundary impedance technique and acoustics IEM technique to simulation infinite flow field is feasible, and adopting acoustics IEM technique has much better performance. Boundary impedance technique is promoted for the concerning of accuracy. The results indicate that ABAQUS is appropriate to solve underwater sound radiation problem and it can satisfy the requirement of project application, which provides a new analysis method.

With the SMA (Shape Memory Alloy) banner model, the effect of pre-stressing and displacement, stiffness and length to the energy dissipation ratio is studied. The two equations, which are of pre-stressing and displacement to the energy dissipation ratio are proposed. The method are put forward to confirm the stiffness and length of SMA . Based on the above analysis, a new pull-press SMA damper is designed. The simulation analysis on seismic response of five-floor frame with SMA damper shows that the displacement and acceleration of the top floor are reduced by 50﹪at least. It verifies that this kind of SMA damper can availably suppress the seismic response of structure.

The feed drive system model of NC precision sphere grinding machine (MD6040) is constructed. Although a large number of researchers pay more attention on advanced controllers, most high performance machine tools still adopt PID (Proportion Integration Differentiation) controller today. In this paper, PDF (Pseudo-Derivative Feedback) controller and PDFF (Pseudo-Derivative Control with feedforward Gain) controller which evolved from PID controller are studied. The performance of PID controller, PDF controller and PDFF controller is investigated by simulation and experiment. Both simulation results and experiment results showed that PID controller has severe overshoot and less rise time, PDF controller has strong robustness and long rise time and PDFF controller possesses the advantages of the other two controllers. PDFF controller is more suitable for NC precision sphere grinding machine feed drive system.

It is much valuable to find a method for predicting the middle and high acoustic characteristics of big and complex structures such as ships and airplanes. Impact of the ring frequency and the damping on the vibration transmission is discussed firstly. Then the feasibility of the model simplification method for big and complex structures whose acoustic characteristics will be predicted is analyzed. At last, the simplification method was applied to predict the middle and high frequency sound radiation of the double complex cylindrical structures. Numerical results showed that the proposed method has the same accuracy as the conventional finite element method and boundary element method, and can be applied to deal with engineering problems.

The different age pleioblastus amarus particle were taken as the raw materials, and the wet-process bamboo powder-boards were made from the laccase-treated powder by hot pressing. The raw material chemical constituents were analyzed. The reactive oxygen species free radicals produced from the laccase-treated bamboo were detected by electron spin resonance. The physical and mechanical properties of the bamboo particleboards were measured. In order to provide some theoretical basis for producing bamboo particleboard by laccase activation, the relations between physical and mechanical properties of bamboo particle boards and chemical constituents, the reactive oxygen species free radicals were researched.

Three kinds of particles which produced by the processing of bamboo flooring were taken as the raw materials and analyzed of chemical constituents. Cellulose crystallinity and the reactive oxygen species (ROS) free radicals produced from laccase-treated bamboo were examined by X-ray Diffraction (XRD) and Electron Spin Resonance (ESR), respectively. Physical and mechanical properties of laccase treated bamboo particle boards which made from surplus materials of bamboo flooring process were investigated. In order to provide some theoretical basis for producing particle board with the surplus materials of bamboo flooring process by using laccase, the relations between physical properties and chemical constituents, cellulose crystallinity or the ROS free radicals of bamboo particle boards were researched.

Plybamboo is commonly made using chordwise bamboo strips. Previous studies have indicated that the bamboo utilization rate and the processing efficiency are low in manufacturing chordwise curtain Plybamboo. This paper presents a study on the manufacturing technology of radial curtain plybamboo form. Radial strips cut from bamboo were glued on the radial faces. The results showed: (1) the bamboo utilization rate of radial cutting strips was 15-20% higher than chordwise cutting strips, and the resin consumption was only approximately 50% of chordwise bamboo strips; (2) however, radial bamboo strips were more subject to lengthwise bending deformation than chordwise strips during drying. This lengthwise bending deformation can be effectively reduced or prevented by placing a hollow rigidity axle in the radial bamboo curtain rolls when using the bound drying method; (3) the hot pressing time of the radial curtain plybamboo form was approximately 50% of the chordwise composite plastic curtain plybamboo.

This paper deals with an on-line mismachining error measurement for curve grinding based on digital image processing. Using CCD camera, the contour of the workpiece’s finished surface is captured and the image is preprocessed for denoising and edge detecting. The worktable is guided by the image of the finished workpiece to follow the path of the finished contour and then the real curve of the finished workpiece is measured by fitting a curve according to the moving path of the worktable. Finally, the machining error is obtained by comparing the measured curve with the theoretical curve of the workpiece. This method is applied to a CNC curve grinding machine MD9040. A measurement experiment is given. The experiment results show that the measurement method offers high detection precision and can be used in wide fields, especially for measuring the parts with complex curve.