Advanced Materials Research Vols. 490-495

Abstract: This paper focuses on the study of digital IF signal simulator's Matlab implementation on the basis of GPS system and GPS navigation signal simulator.It includes the simulator's parameter settings (such as the sampling rate,intermediate frequency), then calculates the sampling signal's code phase and carrier phase by determining the signal's propagation delay. In addition,it introduces and simulates the ionospheric model and the tropospheric model,and corrects the sampling signal's code phase and carrier phase.This paper realizes GPS digital IF signal simulator's Matlab simulation,thus it provides the supporting platform for research,development and testing of the GPS receiver's new algorithm

Abstract: In coal mine the forecast on fire is mainly based on the smoke, gas and temperature parameters to recognize, and sometimes it has leak check and wrong check, therefore a novel method for mine fire based on image processing is presented. First the data are obtained by infrared CCD, then the blaze characters are extracted and they are entered into the GA-improved wavelet neural networks model after being quantization, finally the fire can be detected. The experiment results show that this method can recognize fire signals and it reduced leak forecast, and also it is more reliable and has stronger antigambling ability. It will inevitably play an important role in coal mine safety production..

Abstract: The transient characteristics of mechanical structure of multi-axis force sensor and measuring circuit coupling system is an important index of evaluation of the precision of the maglev system based on the force control. The dynamic model of mechanical structure and coupling system is established. The transient responses curves of mechanical structure and coupling system are obtained through simulation and their transient performances are analyzed respectively. Comparing transient responses of mechanical structure with coupling system, it is shown that maximum overshoot of coupling system is smaller; oscillation number of response curve is less in the settling time; response rise time, peak time and settling time of coupling system is 0.014s, 0.048s and 0.021s respectively. The above data further show that transient characteristics of coupling system can satisfy the control precision of the maglev system

Abstract: The simulation model of some SUV passenger vehicle rear end impact is created in the paper aimed at the furnished vehicle CAD model of some SUV passenger vehicle, using the principle of finite element analysis; according to the relevant test regulations on vehicle rear-end impact. The motion characteristics of rear-end impact, the effect of overall energy absorption, absorption and buffer characteristics of main components, safety of fuel tank and ride safety of crew are analyzed and discussed deeply. The characteristics of collision and the degree of accordance with the safety regulations on vehicle rear-end impact of the vehicle are comprehensively revealed. Moreover, some improved suggestions is proposed, the basis for promoting the rear-end impact safety of similar model is discussed.

Abstract: The multi AC servomotor synchronous operation control system based on DSP+FPGA and a new intelligent PI controller have been designed. The intelligent PI controller can change the structure of controller and parameters dynamically according to the running status of the system, which improves the dynamic performance of the speed control system. In terms of the condition without loading, the experiments about four AC servomotors in different revolving speed have been implemented and The results of experiments show that the system can achieve the high precision control of the operation of multiple AC servomotors synchronously.

Abstract: Paper was removed due to verbatim plagiarism. The original paper was published as follows: Sugahara, K.; Yamamoto, H..; Ouchi, H..; Nakano, Y.., "Numerical Analysis of Near-Field Magnetic Field for Automobile Electronic Key Systems," Magnetics, IEEE Transactions on , vol.43, no.8, pp.3375,3379, Aug. 2007 http://ieeexplore.ieee.org/xpls/icp.jsparnumber=4277913

Abstract: According to the functional requirements of mechanical seismic simulation platform exciter, a new exciter with dual driven slider-crank mechanism is designed to achieve stepless amplitude adjustment and multi-frequency vibration output. Based on the ADAMS simulation software, design features of mechanical seismic simulation platform exciter are verified.

Abstract: For retaking expired operating highway, in order to maintain and enhance the normal operation condition of the highway, we still need continue to operate on highway management and maintenance, relevant departments must also be accurately measure the highway management cost. The paper is on the basis of the analysis of the construction of expired operating highway cost, builds expired operating highway’s management cost prediction model based on the grey model GM (1, 1), and examples verify the effectiveness of the model.

Abstract: This paper studies the speech enhancement technology. A Lyapunov function of the tracking error systems is defined, and the adaptive filter based on FXLMS algorithm can make the error converge to zero asymptotically. It is shown to be suitable to solve the problem of the speech enhancement from computer simulations

Abstract: Tunnel geological environment has the characteristics such as complexity, uncertainty, variability and so on, How to improve the accuracy of tunnel geological advance forecast, guiding the safe construction of tunnel, are always as one of the hot topics on Geotechnical engineering study. This paper introduces the principles, methods and characteristics of a tunnel seismic prediction system (TSP24 system) that newly developed in China, through a successful application on highway tunnel geological forecast, which has verified the accuracy, reliability and economy of this system. The research results can provide reference for other similar projects..