Advanced Materials Research Vols. 490-495

Abstract: The part information model is proposed. It utilizes the second development tool Solidworks API is provided by Solidworks to realize the three-dimensional CAD/CAPP system information exchange and sharing. The overall function model of three-dimensional CAD/CAPP integrated system based on the feature is proposed. Take a box-part for instance, explains the method of part feature recognition and extraction, realize three-dimensional process design based on part information model.

Abstract: The paper takes the 3-tier building structure as research object, and similar model is made based on similarity theory, by optimizing design the parameter of the MRF absorber is obtained, by means of accelerating sensor and data acquisition card, a set of testing system of semi-active vibration control used for building is designed, the effect on shock absorber of MRF absorber is studied and validated, at the same time, providing the theoretic method and proof for the vibration experiment of building structure by MRF absorber.

Abstract: Due to the special process requirements, sometimes the big openings are needed for pressure vessels, which will form a complex stress state in the opening edge. But there is not a perfect design specification accepted by international for the pressure vessels with big openings, therefore detailed stress analysis and strength assessment are absolutely necessary. In this paper, in order to ensure that the structure of a pressure vessel with big openings which is calculated by pressure area method is correct, the finite element method has been used to perform strength analysis. Force characteristics and stress distribution are obtained. The intensity evaluation result shows that the structure is correct.

Abstract: This paper presents a new optimal design method based on genetic algorithm（GA）for broadband linear dynamic absorber. A New definition of the suppression bandwidth is described firstly. Then the method and procedure to optimize multi-parameters of broadband dynamic absorber is proposed. Effects of the natural frequency ratio, excitation frequency ratio, mass ratio, main system damping ratio and absorber ratio on the suppression bandwidth are discussed systematically. Finally the merits of genetic algorithm used for broadband linear dynamic absorber design are illustrated by contrasting it to a numerical method.

Abstract: In attempt to analyze modal shapes and the reliability of the Turbine-generator set, we took advantage of LMS Test.Lab testing system, and made some tests and analysis on the Turbine-generator set shaft, we obtained the modal parameter, such as the natural frequencies, subsidence ratio and relevant modal shapes. Frequency response function fitting is represented to verify the modal identification.

Abstract: Running traction mechanism of shearers is adopted as the analysis object in this paper. The finite element models for the elastic contact analysis between the running gears and pin-rails are created. When the gears are running, the variation principles of contact spots, contact force, and internal stress for the gears and pin-rails at the different contact positions are analyzed. The calculation results show that the maximum stress is located at the edges of the gear teeth for the different contact positions. When the teeth are loaded with the repeated large stress, cracks are produced at the tooth edges at first and then are growing. The tooth breakage is produced at last. Gear chamfers using two circulars at the tooth edges can change the location of the maximum stress and the maximum MISES stress can be reduced by 20% or more. Therefore, the fracture problem of gear teeth is solved basically.

Abstract: The maintenance of equipments in marine ships is a critical issue, in which the security of robustness of the communications between the marine ships and the base present foremost importance. As the communication link confronts bandwidth and delay constraints, it is challengeable to design an appropriate scheme. In this paper, we propose an echo-based information hiding scheme for addressing this problem. The confidentiality and integrity of the maintenance communications can be guaranteed. The robustness of the communication indicates the resilience to artificial tampering. The interaction for maintenance guidance can provide associated text or images via voice communications. Our echo-based method utilizes the sound echo delay to hide the information in the voices. The simulation verified that the scheme is secure and robust.

Abstract: This paper focuses on the research and development of the “Multi-functional Composite Embedded Smart-Skin Antenna (MECSSA) Structure” with load-bearing, shape maintaining and communication capabilities. MECSSA structure consists of top and bottom composite thin facesheet, honeycomb core, 4 by 8 micro-strip antenna arrays located among honeycomb core and some adhesive. Simulation and experiment methods were used to study the performance of MECSSA structure. Through the study we found that adhesive is the significant factor of affecting the electrical performance of MECSSA structure, especially for radio frequency (RF) and it must take into account in the research. There may be two ways to avoid the influence of adhesive: compensation and separation. Three point bending test indicated that the strength of MECSSA structure satisfies design requirements.

Abstract: The method to analysis the strength of planetary trains’ carriers of EPB(earth pressure balance) shield machine is presented in this paper. The structure of the shield machine trains is analyzed and the 3-D solid model of the carrier is built with Pro/E. After the load on the carrier has been dealt with, the strength of carrier is calculated by means of finite element method. The results via ANSYS show that the max stress and strain on the carriers are increasing as the increasing load on it. The max stress is lying on the joint point of the carrier and planetary gear shaft because of the bending deformation of the shaft

Abstract: The parameter of the undisturbed soil cannot be used simply in the engineering for the characteristics varied considerably. So the physics and mechanical characteristics of freeze-thaw soil are very important in the freezing method engineering. The physics and mechanical properties of freeze-thaw soil and undisturbed soil are compared by the experiment. And the data of test are shown that after the samples are frozen and thawed, density , dry density decrease and plastic limit decrease, void ratio increase a little, other physicals are similar. Permeability of mild clay greatly increased. Compressibility of mild clay decrease, but compressibility of fine sand increase. This can be used reference to model test, numerical analysis and project designing.