Applied Mechanics and Materials Vols. 121-126

Abstract: A series of wind tunnel aerodynamic experiments were conducted to investigate the wind loads on the low-rise buildings with arched roofs. The wind loadings were calculated from the simultaneous measured wind pressures data over all of the models surfaces in a simulated open terrain exposure atmospheric boundary layer. With these data the equivalent static wind loads (ESWL) of fluctuating wind pressures acting on buildings frames were evaluated and the results of equivalent static wind loads were compared with the 2006 version design codes of wind loadings on buildings in Taiwan. The design codes suggested the direction of wind acting on the low-rise buildings roofs were normal to the ridges of roofs. In this study results shown, the equivalent static wind loads caused by the approaching turbulent flow may exceed the suggested values by codes. So the peak response of structural frames should be considered carefully.

Abstract: There are some inevitable errors we can’t avoid in the process of powder laser sintering Rapid Prototype Manufacturing Cooling System. If we don’t take some measutes to eliminate the errors , they would influence the system’s operation directly, but if we adopt the traditional method, testing precision can’t meet the increasingly high requirement, while upgrading the hardware system will greatly enhance system cost, which can’t suit the empoldering and using of most systems. In this articles, when the number of sensors is less than 10 (N<10), a new method of data processing was introduced(including cooling water’s temperature, work jar temperature etc. ); use the distributing chart to eliminate inevitable errors, then adopt the method of arithmetic equilibrating and batch estimating to fuse the testing data, in order to estimate the true number.

Abstract: This paper is based on Abaqus finite element software platform and Tosca structure optimization software, with the purpose to improve the strength-to-weight ratio of Z-axis supporting plate. The writer adopts weight topology optimization to carry out finite element analysis, topology optimization analysis and verification to Z-axis supporting plate, thus getting the best material allocation solution. The modal frequency and dynamic performance of the product are greatly improved at the same time when ensuring the static precision of the product.

Abstract: This article analyses the formation mechanism of local cluster of enterprises based on self-organization. First, it explains the meanings of formation mechanism of local cluster of enterprises, then analyses the prerequisite to form local cluster of enterprises, and then, concludes the formation mechanism of local cluster of enterprises, finally, advises the government how to form a local cluster of enterprises.

Abstract: The isothermal elliptical contact elastohydrodynamic lubrication (EHL) problem in ball screw with rotating nut was studied.Numerical solution to the problem was obtained for various parameters with a multigrid solver.Based on work mentioned above,the influence of the working parameters such as the rotating speed of screw shaft and the contact force,on the lubricant oil film thickness and pressure is analyzed .The results showed that, with the increasing loads,the pressure became higher,the film thickness became smaller. On the other hand,when the angular velocity was higher,the film thickness was higher, while the pressure spike was closer to the center of the contact. Because of the spinning, the slide-roll ratio was not a constant.

Abstract: In order to complete the numerical simulation on internal flow and operating characteristics of down hole multiphase pump compress unit, establishing perfect finite element model, the three-dimensional turbulent current fields inside the impellers of compression unit for down hole multiphase pumps were simulated by using ANSYS. The calculation of multiphase flow is based on the standard k-ε turbulent current model. Reference information for the improvement of the pump can be obtained by the analysis of the flow of gas-oil in the channel of pump. Based on the finite method, we analyzed several situations in a pumping period. The velocity and liquid pressure distributing of sucker rod pump is studied in this paper, which may offer some evidences for the engineering design of sucker rod pump.

Abstract: In order to study the influence of shear lag effect of single box and double cell box girder on structure，to make the rigid frame continuous bridge of Wei River grand bridge as the research object, through the establishment of finite element model, the normal stress and shear lag coefficient of the control sections in various working conditions is calculated, and the distribution of the box girder normal stress under shear lag effect is obtained.

Abstract: Graduates feedback system (GFS) is a graduates-based communication platform that integrates enterprises, universities and graduates. This MIS aims to enhance graduates resource use, improve school education quality and university employment problems. This article was clued with the general development process of MIS. It illustrated the main points and some developing tips in the entire course, named requirement analysis, system design, system development and system implement. Under the aid of a large number of documents collected, and the actual survey, it came up with the advantage and application value of the system compared to the domestic and foreign alumni networks. It is believed that the idea of this MIS will provide a precious reference to education for colleges and universities.

Abstract: To study the bearing capacity, ductile, energy dissipation capacity and failure mechanisms of RC frames which Strengthened with CFRP sheet and steel plate, three concrete frame specimens were subjected to the horizontal low cyclic loading. One was loaded up to the failure load, the others were strengthened with CFRP sheet and steel plate after loading to damage, and then were loaded up to the failure load. In terms of cracking load, yield load and ultimate load, the experimental results show that the improved degree of frame strengthened with steel plate is more than with CFRP sheet, on the other hand, regarding ductile and energy dissipation capacity, the improvement of frame strengthened with CFRP sheet is better than with steel plate.

Abstract: To improve the design of complex curved parts and the shortage of reading two-dimensional drawings. This paper explicitly discussed modeling the bottom of a bottle by enhanced modeling and rendering techniques of CAD/CAM. Established the bottom with freeform surfaces in UG to solve the problem of design a part with freeform surfaces, and rendered the bottom of the bottle to express the result of three-dimensional stereoscopic of a part with freeform surfaces. Rendering is setting the material and texture for the model, and then adding lights and setting the background, etc to help solving the problem of identifying a part with freeform surfaces. Finally, we got the features of UG, the advancement, applicability of CAD/CAM and the necessity of expanding it.