Applied Mechanics and Materials Vols. 411-414

Abstract: Among numerous embedded platforms, NetFPGA provides developers with a freely programmable FPGA component to design custom functionalities in networking. However, most hardware projects are developed based on reference designs without embedded operating system. For hybrid developments on multi-layers, there will be some difficulties to apply. On the other hand, due to the limited resources on embedded platform, both performance and flexibility need to be concerned on implementation. And for networking processing, it is quite difficult to adjust control parameters without software environment. Therefore, this paper proposes an integrated architecture using PowerPC processor on NetFPGA and embedded Linux operating system on NetFPGA platform. This not only provides developers with an environment for software execution which added more flexibility, but also enhanced the system to provide more applied possibilities on development.

Abstract: Single precision can only achieve 6-7 decimal places, which does not satisfy accuracy demand in many calculations. Double precision can get 13-14 decimal places, but the resource cost is high. In this paper, effects of data bit-width on digital logic design are studied. The accuracy of different bit-width is determined. Then, addition operation, multiplication operation and matrix multiplication with different bit-width are tested on FPGA platform. The results show bit width and circuit design platform have obvious effect on resource cost and circuit efficiency. Finally, a bit-width based circuit design optimization method is proposed.

Abstract: This article describes the design of a microstrip patch antenna with radiation pattern reconfigurable characteristic, where two monolithically integrated MEMS switches are utilized. By changing the physical dimension of the antenna, its radiation pattern could be changed. Moreover, we present detailed structures of these RF MEMS switches, whose isolation and insertion loss are-23.12 dB and-0.09 dB at operating frequency, respectively. And the resonant frequency of the antenna is 35.4 GHz and the bandwidth is 6.69%. All the results are simulated.

Abstract: This paper aims at various problems encountered in the current power-frequency parameter measurements, analyzed the feasible solutions which not only effectively improved the accuracy of surveying data, but also provided necessary and accurate data for transmission line parameters for the calculation of stability of power system and relay protection setting, and a reliable theoretical basis for the calculation of electric power system and correct setting and selection of various switching equipment. It has been proved through practical engineering verification that, power-frequency parameter measurements has very important significance in improving the safe operation of the power system.

Abstract: Decentralized Robust Feedback Linearization (DRFL) approach based on integrity for multivariable systems is presented. It uses a model observer to compensate the non-modeled dynamics, system uncertainties, and external disturbances of a system. Firstly, the existence of DRFL controllers with integrity is examined. Then, stable regions of each DRFL controller parameters are calculated, and some parameters are obtained by placing suitable closed-loop poles, for meeting the design specifications for the whole control system. The proposed method is applied to an illustrative example. Results demonstrate that DRFL control is feasible and robust for complicated multivariable systems.

Abstract: AC servo controller have the characters of precise position control and fast response, which makes itself promising in the application of numerical control machine. A new line and arc interpolation algorithm is proposed in this paper, which controls the stepping size of z axis by orthogonal decomposition given the stepping size of x axis.The algorithm has the advantages of high interpolation speed. At last, an experiment is conducted to verify the algorithm.

Abstract: The structure, the function and properties of the intelligent temperature control system of the excavator operating room are introduced in this paper. STC90C516RD+ microcontroller is used as the core controller of the hardware circuit. Firstly, based on the working environment, research is done on the anti-jamming performance of the hardware in the system. Secondly, the software is designed and the process of the PID control is introduced.

Abstract: This Paper Puts Forward a New Solution in Terms of Humanized Design---the Combination of Control Method between Speech Recognition and GSM Remote Control System.People can Not only Apply Speaker-Independent Speech Recognition Technology to Control Domestic Appliances and Light System Indoors, but also use GSM Remote Control Technology to Achieve Intelligent Control of Domestic Appliances Outdoors. through a Corresponding Command which will be Processed by the LD3320 Speech Recognition, the System Delivers the Returning Identifier to the STM32 Chip, and STM32 will Control the Domestic Appliances. when Users Outdoors, they can Call Target Phone Number through the Cell Phone to Realize Intelligent Control of Domestic Appliances. this System has the Advantages of High Recognition Rate and Good Stability. the Market Prospect is also Considerable.

Abstract: In this paper, taking integrated process and control platform as the background , did the research on mathematical model of boiler liner and parameters on the performance of the control system. First, created a mathematical model of the temperature of the boiler liner. Second, selected the PID controller to control the temperature control system in the case of the PID controller parameters remained unchanged. Finally, changed the boiler parameters, analyzed and compared the simulation waveforms of different boiler parameters in order to get the conclusion that different parameters had different influence on the static stability of the temperature control system and the temperature control system had anti-jamming capability.

Abstract: For low order process with large time delay, a kind of optimal PI controller tuning method is proposed based on generalized Hermite-Biehler theorem and Genetic Algorithm. Firstly, the stable region of PI controller is obtained by using the generalized Hermite-Biehler theorem. Then the optimum parameters are selected from this region based on ITAE criterion and genetic algorithm. A tuning formula is obtained by nonlinear fitting of optimization result, which has the capability to cover the variety of normalized time delays up to 100. Simulation of Monte-Carlo stochastic experiment indicates that the proposed method has good performance robustness when parameter uncertainty occurs, compared with other four PI tuning methods.