Advanced Materials Research Vols. 268-270

Abstract: For achieving better environmental performance of products or product systems, it is essential to manage total product life cycle. This paper describes a method for supporting product life cycle management by comprehensive product life cycle simulation, which is a basis for designing and evaluating total product life cycle. For life cycle evaluation, it is important to seek for the better product services, at the same time to seek for lower environmental burden and life cycle management costing. For this purpose, a product usage model is proposed, where customer satisfaction is measured by offered product functionality. The same level of customer satisfaction can be achieved by various different life cycle management options. By taking examples of technologically immature short-life products, like mobile phones, effect of difference of required product service quality is investigated, and appropriate product management strategy is discussed for improving product service quality.

Abstract: In order to ensure the efficiency and safety of construction process control and failure analysis for the large-scale construction equipment in water conservancy engineering, which is based on specified equipment for some real engineering practices, namely TC2400-tower belt crane, a multi-body joint simulation dynamical model is given in this paper. Then, the data flow and operational process of the model are analyzed. Finally, a case study based on ADAMS and SOLIDWORKS platforms is performed to verify the validity and rationality of the given model.

Abstract: This paper presents a method for analytical prediction of displacement response and the results from virtual vibrating tests of a washing machine cabinet model. The cabinet was modelled with finite element method in ANSYS software. The input excitation used during the test was from the records obtained from the virtual prototype of a front-loading washing machine during the spin-dry cycle. The simulation results indicated good agreement with the mechanical performance of the actual test system, which could afford better support for designers to explore the robustness of the cabinet.

Abstract: According to the architecture characteristics of the mass data acquisition system in marine seismic exploration, this paper designed a real-time data processing algorithm which can convert the collected time-sequence data to channel-sequence data. A hardware implementation of the algorithm based on FPGA+DDR SDRAM is developed to complete the whole conversion process. Here, FPGA is used to achieve time sequence data receiving, analyzing, preliminary processing and the interface to DDR SDRAM. Two DDR SDRAM’s are used in ping-pang mode to store time-sequence data and to cooperate with FPGA in realizing time-to-channel sequence data conversion. Test results showed that, after applying the algorithm to the FCI in high-precision marine seismic data acquisition and recording system, this arithmetic could realize caching collected data without redundancy and converting data from time sequence to channel sequence without dead time, besides, this algorithm also greatly improved the efficiency and reliability of data processing.

Abstract: The study of the profiles of velocity and fluid flow rate in porous media with cylindrical geometries were made, using Maple, and the results were obtained in terms of the Bessel Functions. Some of them were the generalized forms of the Haugen-Poiseuille Law. The results could be applied to synthetic media such as zeolites. Only newtonian fluids were considered, but it’s possible to consider non newtonian fluids in the future investigations.

Abstract: This study investigates the flow characteristics of microinjection-molded lightguiding plates. This study also analyzes the position of melt fronts on lightguiding plates. Viscous heating, temperature and velocity distribution are utilized to analyze delay or advancement of the melt front experimentally and using three-dimensional (3D) numerical simulation. A slow injection speed reduces viscous heating. As viscous heating decreases, the temperature distribution decreases and plastic viscosity increases. A high plastic viscosity increases flow resistance and melt plastic velocity decreases. The advancing melt front of a lightguiding plate is delayed in this situation. The key of this research is that the plastic melt front can arrive the end position at the same time on filling stage of lightguiding plate for microinjection molding. In this research, the authors find increasing the injection speed can help the previous situation. Experimental results demonstrate that filling in the experiment is very close to that in 3D numerical simulation.

Abstract: Because of the imperfects of traditional induction control system neglecting iron loss, this paper introduced the parallel equivalent resistance of iron loss, and use new mathematical model of induction machine to establish a more accurate vector control system. However, the increased coupling of parameters in induction machine caused by iron loss is undeserved. We simplified the decoupled system and utilize fuzzy adaptive mechanism to make the speed tuning process more intelligent and robust. The load and non-load experiments show that fuzzy PID controller overcomes the shortcomings of the traditional, reduces the detrimental impacts of iron loss, take advantages of the active impacts from it as well. In the new control system, it adapts to both inner and environmental parameters well, the torque and exciting current are smoother and lower. So, it is extremely meaningful and conducive to the realization of the economical speed tuning.

Abstract: Based on an elastic beam model, potential flow theory and N-mode Galerkin discretization technique, the dynamical stability behaviors of fluid-conveyed double-walled carbon nanotubes (DWCNTs) considering geometry nonlinearity relating to the time as variation of the flow velocity are studied. The results show that the bifurcations happen in turn of pitchfork and Hopf types as the flow velocity increases. The vdW forces do not change the bifurcation types but make the critical velocities increase sharply. Furthermore, the vdW forces play a critical role in keeping the synchronization of the time histories of the amplitudes or the velocities of different layers of the CNTs-fluid system.

Abstract: An analytical model for the time dependent characteristic of ion implanted buried gate MESFET have been obtained by solving continuity equation with variation of light , turning ON and OFF in the active layer of buried gate through the optical fiber. This paper provides new insight into the cause of channel conductance variation in an ion implanted buried gate MESFET with front side illumination. At time‘t’ is equal to zero, the light through the optical fiber is turning ‘ON’ and ‘OFF’ has been considered. The channel conductance of the buried gate MESFET evaluated with front side illumination. These results indicate very good performance of the device compared with the other devices like MESFET with back and front illumination. Buried gate MESFET highly used in Aerospace System Technology and Microwave communication.

Abstract: In order to analyze the characteristic of the self-excited cavitation oscillation occurred in an inducer-centrifugal pump-piping system, a novel cavitation dynamic model is present to simulate the dynamic characteristic to capture the limit cycles, the characteristics of inlet pressure and the flow rate. The results of numerical experiments indicate this cavitation dynamic model is very suitable to simulate the characteristics of the self-excited cavitation oscillation; the calculated limit cycle of flow rate vs. inlet pressure is consistent with experiment; the cavitation pocket decreases as the flow rate and inlet pressure rise.