Advanced Materials Research Vols. 756-759

Abstract: According to the error between the model predictive output and the future expected output, ILPC carries out an iterative learning and amending process on the current and the future control input vector, namely performs forecast, iterative amendment, forecast again, iterative amendment again repeatedly in the iterative domain. This paper gives a fast high-precision temperature control systems structure, characteristics and realization method. CARI model and the improved generalized predictive control method are used to improve the control precision of the system, and shorten the response time. The quick high precision temperature control systems structure and realization method are given, and according to the requirements of the task, the existing predictive control algorithm has been improved. Through the experiment, its temperature predictive control systems design scheme and realization method is proved to be reasonable and feasible. It can meet the demands for the expected temperature control.

Abstract: For the modelling and simulation of complex spatial multibody systems, the vector bond graph method is proposed. By the kinematic constraint condation, spatial prismatic joint can be modeled by vector bond graph. For the algebraic difficulties brought by differential causality in system automatic modeling and simulation, the effective decoupling method is proposed and the differential causalities in system vector bond graph model can be eliminated. In the case of considering EJS, the unified formulae of system state space equations and constraint forces at joints are derived, which are easily derived on a computer and very suitable for spatial multibody systems. As a result, the unified modelling and simulation for complex spatial multibody systems are realized, its validity is illustrated by a practical example.

Abstract: Power shortage is one of critical issues stalling the development of wireless sensor networks. This paper attempts to address this issue by means of microwave power transmission. In this paper, we propose a sensor node framework using a high-frequency microwave power transmitting module to allow sensor nodes to transmit power to others. We introduce the process of exchanging power between two adjacent sensor nodes and design a power transmission routing protocol called PTR in this paper. PTR optimizes the power transmission of a whole network so that the power of energy sources can efficiently reach any sensor node in the network. We have done simulations and analysis on this framework and the results are positive.

Abstract: Wireless sensor network ( WSN ) is a kind of energy constrained network, by using data fusion technology, the elimination of redundant data, can save energy, prolong the network life purpose. Data fusion in wireless sensor network can realize different protocol layers, Based on the introduction of wireless sensor network and data fusion related knowledge, prove that the arithmetic mean method is effective, and use OPNET software tool for network simulation, finally, analysis results and conclude, verify effects of the arithmetic average fusion algorithm for wireless sensor network.

Abstract: The design of the wireless distributive data acquisition system has been presented based on MSP430 embedded microprocessor and nRF24C01 module for the native mobile telemedicine. The focus of portable electronic products is Low Power Consumption and accuracy of data acquisition. Pulse data acquisition has been simulated with Self-adapting Selection operation, and the data provides a reliable gist for the prevention, treatment, diagnosis and therapeutic efficacy of cardiovascular disease.

Abstract: According to the predistortion technique of travelling wave tube amplifiers (TWTAs), by analyzing TWTA model proposed by Saleh, the gain transmission function curve and phase expansion function curve of the predistortion circuit are deduced. The linear range of TWTA could be enlarged by using predistortion technique, and invariable gain together with zero phase excursions are reached at the working region of the linearized TWTA. As a kind of microwave and millimeter wave amplifiers, TWTAs find a wide utilization in communication, radar and electronic countermeasure applications. To obtain high output power, TWTAs are usually working at their saturation region where severe nonlinear distortion appears. The nonlinearity manifests gain compression and phase excursion. For digital communications application, the nonlinear distortion increase bit error rate, and this limits system efficiency. For electronic countermeasure applications, the nonlinear distortion limits the output power obtainable at the carrier frequency, and this limits the obtainable efficiency of the system. So insights into measures to improve nonlinearity of TWTAs will benefit wireless communications systems and electronic countermeasure systems. Predistortion technique is one of the best choices ^[1,2,.

Abstract: Welding had always been paid attention to by the automobile manufacturers as one of the four technologies. This paper does process plan and simulation validate for BIW welding line using the virtual simulation technology based on DELMIA, including calculate the mainline beats and to determine the station number and function, simulate according to the layout, and output offline program at last. Practice had proved that this method can greatly improve production efficiency, reduce production costs, avoid delaying the progress of the project due to the pre-design problems.

Abstract: Alternating current (AC) machine speed regulation system plays a very important role in our industrial and agricultural production. This paper focuses on the three-phase asynchronous motor which account for most of the proportion of the AC machines. Firstly, this paper establishes three mathematical models of asynchronous motor based on dq coordinate system and introduces the principle of V/f speed-adjusting for asynchronous motor, and then the paper builds the simulation models of V/f speed-adjusting control system for asynchronous motor based on Matlab/Simulink. The simulation results of the V/f speed-adjusting control system verifies the correctness of the simulation models and the principle of speed regulation.

Abstract: In this paper, the recursive backstepping nonlinear control method is proposed. Based on the Lyapunov theory, the controllers are designed to achieve the new hyperchaotic system globally, asymptotically stabilized at the equilibrium point. Furthermore, a robust control method combining backstepping and sliding mode control techniques is used to control the system to another equilibrium point. Numerical simulation results show that the proposed control schemes are effective.

Abstract: A novel configuration for a novel temperature compensated amplifier is presented in this paper. This amplifier exhibits high performance including Return Loss is well blew-12dB from DC to 6GHz, At 3.1GHz, the typical gain is 14.1dB, noise figure is 3.0dB, 1dB compression point is 13.9dBm.with insensitivity to temperature.