Applied Mechanics and Materials Vols. 536-537

Abstract: This remote on-line automatic monitoring system is designed based on WSN and GPRS Network, aiming at solving the present problems of low performance in field monitoring of reservoir water, forecasting sudden water pollution accidents, reporting important hydraulic process such as reservoir operation. The system is simulated laboratory water quality analysis process, and achieved long-time unattended reservoir water regimen remote on-line monitoring and optimized reservoir water resource management. By adopting embedded operating system μC/OSII, the system has the function of parallel processing of multi-tasks, including an electrochemical sensor control circuit of lifetime-prolong. The bus mode is introduced to management software design of receiving and analyzing unit. Buses that associated with each component of management software are well connected. All of the above make the overall structure reasonable and orderly.

Abstract: This paper researches the corresponding inference-machine, which can adapt to complexity of the net-topology, the diversity of the operation task and the flexibility of operation mode. Multi-agents share information and cooperate to generate the right operation sheets. The system is used in one county power dispatching center.

Abstract: The implicit function theorem and the mean value theorem non-affine function of the system into an affine form, and then RBF neural network approximation virtual control and actual control signals desired. Finally Lyapunov functional theory and backstepping method are used to design a self-adapt tracking control scheme. The proposed control scheme can guaranteed to achieve better tracking performance, thus avoiding the problems caused by the high-gain control affine term sector caused by design problems and overcome loop controller. In order to solve practical engineering control problems provides a theoretical basis and can learn from the ideas, and finally through numerical examples to demonstrate the effectiveness of the proposed method.

Abstract: The fuzzy-PI dual-mode control was designed and applied to control speed loop in feed system of ADGM25 to improve its response characteristic and stability. In order to observe its control ability, the fuzzy - PI dual-mode control and PI control were adopted respectively. The simulation of the feed system was finished by using MATLAB/Simulink. The results show that the control performance of fuzzy - PI dual-mode control is better than the performance of conventional PI control, the maximum over-shoot and setup time decreased by 13%,0.05s respectively.

Abstract: The authors consider problem of an accurate system identification and reproduction of control objects output signal. Also, this paper offers a solution of a control objects transfer function determining task by its step response using the Real interpolation method. An ability of using non-uniform sampling period is a characteristic property of this approach. Numeric examples are shown. Also, an ability of more than half of signal samples omitting with, however, acceptable result is shown.

Abstract: This paper proposes a novel asynchronous differential measurement method to compute the time varying network induced delay which exists in each period of networked control systems. It is independent of the whole networked clock synchronization and can compute the real-time system delay during a single period. System structure is designed as a distributed network control system which consists of a network scheduling manager, many sensors nodes, and many controller/actuator nodes. Network model adopts Master/Slaver communication industrial Ethernet. Finally, a numerical experiment is given to demonstrate that, this method has strong potential to improve the performance of system with network induced delay and proves its validity and effectiveness.

Abstract: The fluctuations and uncertainties of wind power increase the frequency regulation pressure of conventional power plants. This paper introduces an active power control strategy with auxiliary frequency regulation function of wind farms. With this active power control strategy, wind farms can work in normal operation mode or in auxiliary regulation mode. Wind farms in normal operation mode can trace the power command to the utmost extent. When the system frequency drops large, to respond this change, the wind farms can switch to auxiliary regulation mode automatically. Simulation results show that the wind farms can assist the conventional power plants to regulate the system frequency effectively.

Abstract: In order to improve the efficiency of the coated seed dryers, improve the drying quality and reduce energy consumption, the adaptive control technology of coated seed dryer was studied. Detection system for temperature measuring, material level measuring, and wind speed and direction measuring were fixed on the drying equipment. According to the detected data, the adaptive control system controlled the dryer blade to adjust the temperature and intensity of air intake. This technology accurately controlled the drying air temperature, moisture and moisture content in the seeds. The test results show that the drying efficiency is 1.38 times of the original dryer, while the power consumption reduces to 40.05%, and intake air temperature reduced 19.84°C, which can improve the seed activity.

Abstract: This paper investigates the problem of H_infinity filtering fornetworked control systems (NCSs). Based on the measurementquantization of output signal before transmitted through network, asampled-data system with consideration of both network-induced delayand data dropout is modeled as a filtering-error system with twoadditive delay components in the output and, the problem ofH_infinity filter design is solved accordingly. An illustrativeexample shows the effectiveness of the proposed method.

Abstract: Wire tension as well as wire feed should be controlled tightly for the geometry and corner accuracy of wire-EDM. A closed-loop wire tension control system for Micro-Wire-EDM is presented to guarantee a smooth wire transport and a constant tension value. To keep smooth wire transportation and avoid wire breakage during wire feeding, the reel roller is modified and the clip reel is removed from the wire transport mechanism. A genetic algorithm-based fuzzy logic controller (FLC) is proposed to investigate the dynamic performance of the closed-loop wire tension control system. Theoretical analysis and experimental research demonstrate that the developed wire transport system can result in satisfactory transient response, steady-state response and robustness. The proposed FLC can obtain faster transient response and smaller steady-state error than PI controller.