Advanced Materials Research Vols. 143-144

Abstract: Laser cladding forming (LCF) is one of the new developed advanced manufacturing technologies. It integrates the advantages of rapid prototyping manufacturing and laser cladding surface modification, and three dimensional near-net-shape metal components can be directly manufactured without dies. Due to the dramatic heating and cooling characteristics of laser cladding forming process, the cladding layers is liable to crack, which greatly impedes the further and wider application of this technology. In this paper, numerical simulation on the three-dimensional transient temperature field and stress field of powder-delivery LCF has been carried out with parametric programming methods. The temperature field, temperature gradient and cooling rate of the laser cladding layer have been obtained. The influences of laser power and scanning speed on the temperature gradient and cooling rate of the cladding layers, especially the cooling rate of solid-liquid interface of the melt pool have been studied, which is tightly correlated with the cracking generation of the deposited layers. According to the simulation, process parameters were optimized to minimize the cracking possibility; LCF experiments have also been conducted to verify the simulation results.

Abstract: Most of the input of parametric design system is the specific structure parameter, which is in a detailed design stage. To promote it into conceptual stage, the function-structure mapping problem is proposed. To solve the problem, the function -structure mapping mechanism which is based on logical view and in the framework of axiomatic design is established, the mapping model is solved by optimization method and the mapping procedure is integrated with parametric design system. Function requirements are mapped into a parametric model directly. Finally, a forklift design process validates the method and shows its advantage.

Abstract: The fracture mechanism of fan blades in the subway system is analyzed by using the finite element method (FEM) and some experiments. Firstly, the mechanics performances of blade materials are obtained on the basis of the hydraulic testing machine. Then, the fracture surface of blades is measured with a scanning electron microscope (SEM). In the end, the natural frequencies of rotation blades are estimated by the means of nonlinear FEM program. It is shown from both the experiment and simulation results that the mechanics performance of blade materials is lower than its national standard, which is due to much bigger gaps and some inclusions in the cast fan. When voltage rises, the 79th natural frequency of blades becomes too approaching the rotating speed of fans easily to resonate. The biggest stress location of fan blades caused by centrifugal force, wind load and resonance is consistent in the fracture place, so the design of fan blades should be improved and optimized for preventing fracture.

Abstract: If the tourism e-business system has the characteristics of platform independence, scalability and portability, it will be useful for improving the level of service and management of the tourism, and further quicken the step of tourism industry. Web Service provides a kind of new distributed computing technology; it can embody business application services by standard XML protocol and information format on Internet or Intranet. According to the demands of a typical tourism business platform, this paper designed a loosely coupling and easily scalable system scheme, what’s more, carried it out in the final. All attained the expect goal.

Abstract: In this paper, we study the concept of the right twisted smash product algebra A*H over weak Hopf algebra. Let H be a weak Hopf algebra and A an H-module algebra, using the properties of the trace function we describe the finiteness conditions for H-module algebras.

Abstract: Isolators are included in the new earthquake-resistant standard. This article analyses some questions on base-isolators and presents a non-linear dynamic computing-model for the time-history. A corresponding computer program is also compiled. With the program, the earthquake response of a isolated structure including the displacement, acceleration and the shear force of each floor are calculated and compared with those of the same structure without base-isolation. It has been found that base-isolation has important realistic significance in mitigating earthquake disaster effectively and has enormous economic and social benefits. Therefore it is a kind of extremely popularizing and applying new technology.

Abstract: In the vibration isolating foundation buildings, build strong earthquake observation system, at the same time, join the seismic observation to this system, underground observation is carrying along with the observation of the seismic response on the ground and the buildings. The dynamic accelerator-type apparatus applied in the system, comes into being an accelerator-characteristics from 0.05HZ to 50HZ by electronics feeding back, enormously decrease affects of super low frequency interference and the linear and dynamic ranges can suffice the actual functions, avoids obviously errors of displacement-type apparatus in low frequencies, acquires satisfied effects.

Abstract: In this paper a face location technology based on gradient distributions is presented. It begins with vertical location by use of vertical integral projection on the two-valued image of the original image, and then proceeds with horizontal location according to the distributions of gradient direction. Experiments have proved this technology fast and efficient.

Abstract: Based on the different feed-ratios to the concentrations of initiator((NH4)2S2O8), acrylic acid, acrylamide and prevent-polymerization agent (isopropyl), this article discusses the inherent viscosity of the polymeric soil consolidator and the test of hardening performance. Experiment results indicate that: 1) the relationships between different feed-ratios and inherent viscosity are as the following: with the increase of initiator charging quantities, the sample's inherent viscosity rises, while with the increase of acrylamide charging quantities, the sample's inherent viscosity decreases. When the charging quantity of isopropyl is 6.750 g, the sample's inherent viscosity reaches the max value 32.47 ml•g-1. 2) The addition of polymeric soil consolidator into the soil can improve the performance such as the resilient modulus and california bearing ratio significantly.

Abstract: The paper presents a novel method to cluster users who share the common interest and discover their common interest domain by mining different users’ search behaviors in the user session, mainly the consecutive search behavior and the click sequence considering the click order and the syntactic similarity. The community is generated and this information will be used in the recommendation system in the future. Also the method is ‘content-ignorant’ to avoid the storage and manipulation of a large amount of data when clustering the web pages by content. The experiment proved it an available and effective way.