Advanced Materials Research Vols. 760-762

Abstract: For the large number of applications in the real environment of reader of the central control and more practical decentralized control approach to management, analysis and point out their inadequacies, A network structure, which provides a good management and control of the reader and meets the demand of its application in the real world, is proposed and its demonstration system is accomplished. On the basis of central control, the structure can conduct distributed control and complete different operations wanted. Furthermore, it has higher reliability and flexibility , is more easily maintained and more open and has higher coordination.

Abstract: typically, integrity measurement technology for Java application is based on the whole file, which is too coarse to meet different requirements. In this paper, we propose a novel fine-grained integrity measurement method for Java application: trusted class measurement module (TCMM), which is a class integrity measurement method according to organization structure of Java application file. It not only satisfies necessary trust but also has less impact on system performance.

Abstract: According to a detailed study of the fault tree model of the flight control system about Boeing 777, a pre-program was established for the fault tree. The minimal cut sets of the treetops event was calculated by Fussell-Vesely algorithm. And the directed graph search process based on DFS and fault tree module searching method based on double DFLM was used to achieve modular decomposition of fault tree. Therefore, a better structure tree and better rules generate. Finally, it combines the fault tree fault model with the ARINC624 specification to achieve communication requirements between the central maintenance system and flight control system. The Boeing 777 maintenance model was realized.

Abstract: As one of the developing provinces of China, Anhui Provinces Urban management is always accomplished by the government which is thought in the very traditional way by now. With the higher level of the urbanization and the constant expansion of the city, the soaring problems in urban management are series of tasks that are especially difficult to conquer, so the traditional urban management pattern can no longer exist in the Information Century.

Abstract: This paper proposes a kind of improved variable integral PID control algorithm. Simulation results show that the variable integral PID control algorithm improves the system quality compared with the normal PID algorithm. It overcomes the problems of overshoot and integral saturation in the normal PID algorithm. With the seldom parameters, we are easy to set it.

Abstract: In order to improve the level of automation of small and medium-sized casting enterprise, the automatic control system for casting equipment based on PLC is designed. It uses SIEMENS PLC226 as the core control unit to complete the following processes [: 1).Automatically goes fetching molten iron from induction melting furnace. 2).Automatically positioning casting holes and casting molten iron of setting weight into them. The system uses the laser ranging sensor to position casting holes according to the distance between casting position and the ground, and the weight of molten iron is measured by the weighing sensor. The system uses SIEMENS-TP170B touch screen as upper computer to set and display relevant parameters. After repeated experiments, the design has met the requirements: precise positioning, reliable weighing and automatic casting.

Abstract: This paper discusses the problem of robust control for a class of nonlinear uncertain singular systems with time delays. Considering the nonlinear disturbance link to uncertain singular systems with time delays effects, the design idea of robust controller is presented. Using Lyapunov stability theory and linear matrix inequality (LMI) method, a robust controller design example of such nonlinear uncertain singular systems with time delays both in state and output is given. Under nonlinear uncertain functions satisfying Lipschitz condition, a sufficient condition of such nonlinear uncertain singular systems which are asymptotically stable and satisfy the robust performance is obtained. Finally, a numerical example is given to show the applicability of the proposed method.

Abstract: In this paper, for parallel operation of the three-phase PWM inverter control system, we put forward and set up the equivalent grid inverter mathematical model. In the process of grid inverter equivalent model is discussed, for the three-phase inverter system is a nonlinear system, in order to facilitate the performance of the system analysis and design of the control system, the transfer function of the system were analyzed to the linearized system. After the linearization control the theory system can be discussed using the method of classical. On the premise of system average model we get the static working point system, according to the law of small signal, we can obtain the small signal mathematical model .At the same time, discusses the three phase inverter design of double loop control system.

Abstract: In recent years, with the rapid development of science and technology, the ultrasonic flowmeter has been widely applied. It measures the flow of liquid by using the liquid velocity information of the ultrasonic transmits in the liquid. The advantages of the meter are non-contact, no pressure loss, low cost, simple structure, wide measuring scope. In this paper, by absorbing and referring to the domestic and foreign advanced technology, the author developed an ultrasonic domestic gas meter based on transit-time difference method and MSP430.And it can measure fluid flow accurately. Experiments show that the system is stable and reliable, test data has good repeatability. The system lays a good foundation in developing the high-performance ultrasonic flowmeter in the future.

Abstract: A grid voltage vector oriented proportional resonant (PR) control strategy is applied to the grid current control of the float-type wave power generation system. Compared with the conventional double closed-loop proportional integral (PI) control method, the proposed multi-frequency PR control method can realize zero steady-state error in AC input signal in the stationary frame, without complex coordinate rotation transformation and decoupling control. The overall wave power generation system model is built with Matlab/Simulink to evaluate the performance of the PR control method. Simulation results have shown that the PR control can well improve the robustness and the power quality of the float-type wave energy conversion control system.