Applied Mechanics and Materials Vols. 55-57

Abstract: Neural network with Levenberg-Marquardt back-propagation training is widely used in curve fitting, according to its fast speed and free from over-fitting. In order to solve the issue on local minimum that may be found in Levenberg-Marquardt back-propagation with early stopping, and to get optimum number of hidden neurons, the least mean test errors algorithm was used in repeatedly training the three-layer feed-forward network with variable structure. Furthermore, the trained network was used for curve fitting of the radiation spectrum of blast furnace raceway. The results on spectra modeling of blast furnace raceway showed that this algorithm presented a better fitting ability, characterized by the reservation of the details of the original spectra and better generalization ability.

Abstract: Large-scale Ni-based super-alloy sheet has been prepared by electron beam physical vapor deposition (EB-PVD). Microstructure and the dislocation structures in the γ-γ′ double phase alloy under different temperature after tensile strain are studied with Transmission electron microscopy (TEM). The results show that the dislocation glide in single slip system and shearing mechanics, the dislocation climb with part shearing, absolute dislocation climb and cross slip, dislocation round are a course of the interacting degree between dislocation and γ′ phase gradually weakened under the tensile temperature from room temperature to high temperature, so as to decrease materials strength and increase plasticity.

Abstract: Constant stress tensile creep tests were conducted on an AZ 91–25 vol.% Al₂O₃-SiO₂ short fiber composite and on an unreinforced AZ 91 matrix alloy. The creep resistance of the reinforced material is shown to be considerably improved compared with the matrix alloy. The creep strengthening arises mainly from the effective load transfer between plastic flow in the matrix and the fibers. Microstructural investigations by SEM revealed good fiber–matrix interface bonding during creep exposure. Short fibers have a great function in load bearing and load transfer, and greatly hinder the dislocation movement, thus enhancing the creep resistance of the composite. Damage and multiple rupture of aluminum silicate short fiber, quality of the interface combination between aluminum silicate short fiber reinforcement and the matrix, are two important factors of the creep deformation microstructure process control of Al₂O₃-SiO_2(sf)/AZ91 composite. The creep mechanism of the composite is dislocation and grain boundary sliding control.

Abstract: As product varieties increase and life cycles shorten, the need for rapid product development becomes critical to maintain competitiveness in the market. Reverse engineering technology enables us to quickly create the CAD model of product. Rapid prototyping is another technology that can shorten the product development time by fabricating the physical prototype of a part using layered manufacturing technique. And how to integrate these two technologies to facilitate rapid product development is an important issue. Haptic modeling has the advantages of allowing the user to touch, feel, manipulate, and model point cloud in a 3D environment that is similar to a natural setting. A high-quality STL file can be obtained from the haptic modeling system which is ideal for rapid prototyping. In this paper, a novel method of integrating RE/RP for rapid product development based on haptic modeling is presented, which can increase the efficiency for RE/RP integration and promote product innovative design. Case study is also given to demonstrate the feasibility of the proposed method.

Abstract: Climate change is emerging as one of the most miscellaneous expressions of the global change nowadays. It potentially affects ecosystems including water resources. The change of climate also has significant impacts on the availability of water, as well as the quality and quantity of water that is available and accessible. Aiming at studying the effect of climate change on water resources, 25 years collected secondary data of both climatic and hydro-meteorological stations were used and Statistical analysis was performed using ORIGIN PRO 8.0 Software. The study linked the surface elevation of Lake Kivu variation with respect to climate change where the level of the lake matches to pluviometric and anomalies values. Finally, the statistical analysis could not directly link the temperature variation with that of surface water level in the lake. Climate change is real and happening now and surely affects water resources among others making an urgent need to control anthropogenic inputs into the atmosphere, one of the factors forcing climate change.

Abstract: To overcome the shortcomings of the traditional passive-radar-seeker(PRS) for anti-decoy, a complex angle measuring method is proposed in this letter. The complex angle measuring method consists of monopulse angle and spatial spectrum estimation, two angle-measuring units. PRS can get the angle high-resolution features through the complex angle measuring method. So it is possible that PRS confronts decoy. Finally, the simulation results verify the feasibility and anti-decoy capacity of the complex angle-measuring method.

Abstract: Vehicle bodywork attitude measurement has been important in automotive technology. This paper presents a non-gyro bodywork attitude measurement program. Using a three-axis acceleration sensor output real-time body posture through BP neural network. Program skillfully made physical model and the algorithm simple according to the characteristics of motor cars. Taking advantage of the nonlinear function learning and generalization ability of ANN, the system made the input three-axis inertial acceleration values of harmful components filtered so as to mapoutput Attitude. And finally, it presents the data of experiments. By taking full advantage of ANN which precessing in parallel, and good at dealing with problem uncertainty, this program provides a solution of calculating real-time bodywork attitude, while with minimal hardware overhead.

Abstract: For mechanical reliability design with more random variable parameters, if the parameters are queued with their impact on the sensitivity of mechanical reliability, which will be as random variables with relatively high impact, while low-impact will be determined variables, thus would simplify reliability analysis due to the random variable number reduced. With cylindrical helical spring as an example, applying the variation coefficient method, the reliability sensitivity calculation of shear stress and deformation is discussed, and the impact on the reliability of cylindrical helical spring by changing the random variables is also studied. Using the variation coefficient method we can obtain the reliability sensitivity of cylindrical helical spring quickly and accurately, which provides a theoretical basis for the reliability design of cylindrical helical spring, and has greatly improved the reliability analysis efficiency of cylindrical helical spring.

Abstract: This paper presents the results of the study taken in ThaDua Wastewater Treatment Plant of Vientiane city to investigate the Use of municipal sludge with soil on Marigold flower growth in pot experiments. Sludge samples from the rice farm were examined periodically during the period from February to June 2010 using the chemical analytical method for soil, Organic matter (OM) was measured with volumetric analysis using Walkley and black method. The pH value was measured in a 1:1 (w/v), using pH meter. The plant was grown for 75 days, approximately 2.5 months (between April and June 2010). The bacteriological and chemical characteristics of the sludge after centrifuging were measured in order to establish the possibility of land disposal. And the Results for Marigold flowers as the chosen for the experiment, were that all mixtures of castings (C) with PP, PBS, except 3 PP: 1 C (v/v), increased the growth index of plants.

Abstract: This paper empirically studied knowledge transfer between manufacturers and suppliers in the auto manufacturing supply chain. We focused on different suppliers based on merchandise they supplied for auto makers, and analyzed their impact on knowledge transfer in two directions: from manufacturers to suppliers, and from suppliers to manufacturers. Results verified that the former direction of knowledge transfer was significantly impacted by supplier’s roles, but knowledge transfer from suppliers to manufacturers could not be perfectly explained by supplier’s roles. This paper theoretically links suppliers’ role with knowledge transfer between auto makers and suppliers, and the results can assist firms choosing right knowledge transfer strategies according to different suppliers’ roles.