Applied Mechanics and Materials Vols. 143-144

Abstract: To mitigate multiple access interference and improve the system capacity, an effective multiple access scheme, called GCDMA, is proposed. Exploiting the IDMA iterative multiuser detector in each group, the intra-group interference can be effectively handled. Analysis and simulations demonstrate that the proposed technique outperforms the conventional CDMA in terms of both system capacity and bit error performance. Lower complexity of the proposed scheme can be achieved than CDMA and even IDMA.

Abstract: Wax crystallization characteristics, properties of viscosity-temperature and cold rheological properties of crude oil systems with different water cut are studied to analyze the feasibility and advantages of developing temperature drop gathering and transportation in Weixing Oilfield. On the basis of the characteristics of single pipe loop gathering and transportation technological process, an optimization mathematical model for oil gathering and transporting system operation is established, which objective function is the minimum energy consumption of the system. And to solve the model, the hierarchic optimization strategy is adopted. Optimization results of No.1 department and No.2 department showed that the water blending temperature is reduced more than 8°C and the water blending amount is decreased 20%. According to the optimization scheme, the saving on gas and electricity are 7.12×10⁵m3 and 8.92×10⁵kW•h each year.

Abstract: The application of uCOS-II and LabVIEW in the development of Stirling Engine fuel supply electric control system was described in this paper. In embedded system, a control program with multilayer structure was designed based on uCOS-II. In upper computer, a LabVIEW virtual instruments IDE was used to achieve features such as remote control, identify series number automatically, display and record signal in real-time. The operation of the whole control system was proved precisely and stability through experiment.

Abstract: The research is about the design of fuel cell measurement & control system based on the graphical and virtual instrument technology. The hardware platform of this system is mainly based on NI Company's data acquisition products and the software design is based on the development environment of LabView (Laboratory Virtual Instrument Engineering Workbench). To guarantee the data transmission's accuracy and immediacy, CAN bus and Ethernet are used for the communication between the control modules and the host computer. Through the test, this system meets the requirements of the Proton Exchange Membrane Fuel Cell's measurement & control. And this system has many advantages, such as friendly Human-Machine Interaction, stability, reliability and anti-electromagnetic interference.

Abstract: To improve tracking precision and increase the utilization of solar energy, the solar automatic tracking fuzzy PID control system based on ARM is designed. Embedded microcontroller 32-bit ARM processor is the core. A kind of mixed tracking mode is adopted, and it combines photoelectric tracking mode and solar trajectory tracking mode. In the solar trajectory tracking mode, the fuzzy PID segmented tracking control method is put forward. The fuzzy control and PID control are combined to control the system. If the system's angle deviation is large, PID control is adopted, else fuzzy control is adopted. And the controller can be automatically switched control mode according to the size of angle deviation. Matlab simulation results indicate that the solar automatic tracking system with fuzzy PID control has a good dynamic characteristics and high tracking accuracy, effectively improves the photoelectric conversion efficiency.

Abstract: Based on the mathematical model of quarter car body model being put forward, the indoor platform experiment of quarter car body with hydro-pneumatic suspension system was done. During test, the parameters of dynamic wheel load along with the change of vibration amplitude and frequency were investigated. The results show that: the cycle of acceleration of sprung mass has half cycle lag than unsprung mass, and the main parameters of dynamic wheel load has increased significantly along with the increase of vibration amplitude and frequency. At the same time, through analysis the acceleration time responses of sprung and unsprung mass, it can be shown that hydro-pneumatic suspension has good anti-vibration performance.

Abstract: Hydraulic Control Unit(HCU) is the actuator for braking force distribution of Electronic Stability Program(ESP), the modeling and simulation of HCU have significant impact for ESP control logic research. According to the research on scheme of HCU hydraulic system, HCU model is establishes based on AMESim, and calibrates the property parameters of hydraulic component. A test platform for ESP system research is built. By comparison of results between test and simulation, the HCU model can well describe the property of HCU of test car environment, provide accurate actuator model for ESP development simulation and ESP pressure estimation algorithm.

Abstract: Based on the research on the quality of grinding surface of engineering ceramics, the engineering materials can be widely used. The ultrasonic grinding surface of the ceramic plate is discussed in this paper by dividing regionally. Concentrating on how the edge quality affects the surface topography, the white-light interference measuring techniques is used to observe the topography of the grinding surface.

Abstract: An algorithm based on the differential evolutionary (DE) computation is proposed to evaluate circularity error. It is a heuristic evolutionary algorithm based on population optimization .In the meantime, the suggested method is used to solve the minimum zone circularity error. Compared with other methods, the results show the presented method has very strong self-adaptive ability to environment and better global convergence. Examples proves that the proposed method is effective, convergence and robustness in the process of optimization. And this method makes the circularity error evaluation more accurate.

Abstract: Three kinds of data transmission standards of IGES, parasolid and STEP on the SolidWorks and ADAMS software were contrasted to get the Parasolid for the most suitable software standards. CATIA 3D software has powerful function of modeling, but ADAMS has poor function of modeling. It has built the four feet completion institutions of 3D modeling by CATIA, then through among the middle media of SolidWorks software format to conversion and import CATIA 3D entity modeling into ADAMS/View environment to make up for the problem of insufficient ADAMS modeling ability. This paper focused on the discussion of data exchange process among ADAMS, CATIA and SolidWorks software.