Advanced Materials Research Vols. 798-799

Abstract: It is known that design means the art of times. As the industrial development enters the high-tech stage in current society, handicraft, industry and high technology have integrated with each other well. Moreover, informatization has been rapidly applied in the various aspects of human life. However, with the advent of digitalized era, design now lies in the age of reconstructing languages.

Abstract: For better research on rock breaking mechanism of shield disc cutter, a kind of vertical experimental platform was designed after the characteristic analysis of existing linear cutting rig, using rock box turning to realize the rotary simulated motion of shield disc cutter. Compared with the linear device, this experiment platform overcomes the lack of real simulation of shield disc cutter movement condition. The design of comprehensive experimental platform was described particularly from the three aspects of electronic control system, hydraulic system and an adjusting device for cutter space. On the produced platform, which is the first one in China, the experiments of rolling experiment under three cutters sequential indentation were performed. The experimental data and analysis result were basically consistent with engineering data and simulation result based on RFPA. The correctness of design scheme, advancement and scientificalness of experiment platform were confirmed, with the hoping of providing dependable platform for the research on rock breaking mechanism of shield disc cutter.

Abstract: Aiming at the mass flow and high speed operating condition of roots pumps, the evolutionary structural optimization method was used to optimize rotary lobe of roots vacuum pumps. During the optimization process, filtering and removing algorithm based on the join traits of distortion elements were proposed for solving the structural mutation phenomenon. In this way, the ESO method was improved to ensure the stability and continuity when optimizing. Optimizing respectively with 5 different initial rejection ratios, then a reasonable structure was obtained by finite elements contrastive analysis. Results of finite element comparative analysis indicate that the new structures have better stress distribution, and the material utilization is maximized when applying the inertial load. The maximal stress, strain and deformation of new structure decrease by 17.7%, 17.5% and 18.7%, respectively, and the volume decrease by 55% comparing with primary structures, thus the safety and stability of roots pumps have a significant improvement at the high speed and mass flow operation conditions.

Abstract: In China, for 3D stratum visualization computer assignment design software research is still very backward, but does not prevent him is widely used in geological exploration. This paper introduces the concept of computing into visual and significance of three-dimensional visualization and numerical model artifacts, computer software and examples in this paper, the 3D stratum visualization computer assignment design software in the actual application of geological exploration.

Abstract: The ultimate tendon stress is the key to calculation of flexural capacity in reinforced concrete beam prestressed with external FRP tendons (RCBPEFT). Based on the theory of equivalent plastic hinge zone, the general formulas for calculating the ultimate tendon stress increment and ultimate tendon stress in RCBPEFT are therefore proposed. Comparisons indicate that the predictions are in good agreement with the test results.

Abstract: Simulation study of the quarter car model was carried out in this paper. The influence of the stiffness of the suspension spring and the damping on the performance of vehicle suspension system was analyzed by the evaluation indexes: transfer function of body acceleration, transfer function of suspension dynamic stroke, transfer function of tire dynamic deflection. The simulation results shown that increasing the stiffness of the suspension spring would reduce the vehicle's ride comfort and increase the value of the first natural frequency of the sprung mass. And increasing the damping would reduce the peak response of the body acceleration which increasing the vehicle's ride comfort, but at the cost of increasing the high frequency vibration.

Abstract: This paper presents several kinds of energy-regenerative shock absorbers, which all exist some problems. Then, we put forward a novel type of shock absorber: Hydraulic Energy-regenerative Shock Absorber (HESA). In this paper, we focus on damping characteristic and energy recovery of HESA. Its feasible that damping force can be increased by adding a damping orifice in the extension stroke. The damping characteristic of HESA meets the requirements, whats more, it has great potential on energy recovery.

Abstract: The virtual reality is a dynamic 3D environment of a emulated world produced by the computers, which can make the operators feel being personally on the scene. People can obtain perceptions they want and experience the detail things in virtual world by operating these hardwares such as joy sticks, safety goggles, the mouse action, earphone and so on. In this paper, the distributed virtual reality system was introduced and we analyzed how to establish this system.

Abstract: With the fast development of science,all kinds of new and high science and technology are corresponding applied to the people's daily life, and it has been accepted and applied to all aspects by them. The emergence of the computer is a typical example, it plays a good role in promoting the development of science and technology, and the connection between the computer will rely on the network communication. In this paper, the main methods and applications of multiplexing technology in network communication have been analyzed and discussed.

Abstract: In the ultrasonic detection of small-diameter steel pipe with thick wall, the quality of ultrasonic echo signals is the foundation for the pipeline flaw identification and feature extraction. In this paper,a de-noising method of wavelet packet based on threshold is proposed for the limitation of soft and hard thresholds. The ultrasonic wave pipeline detection signal contaminated by noise is de-noised by this method. Moreover, the contrastive analysis is performed among the wavelet packet transform based on adjusted threshold, original ultrasonic echo signal and the wavelet packet transform based on default threshold. Experiment results show that the noise reduction effect of the wavelet packet based on the adjusted threshold is obvious and the SNR of signals is also improved.