Applied Mechanics and Materials Vols. 347-350

Abstract: this paper uses a new type of FRI (Finite Rate of Innovation) sampling pattern based Sub-Nyquist sampling model breaked through Shannon theorem that it can get accurate signal reconstruction based on signal information rate, which requires the sampling frequency lower than two times the max signal frequency. We apply the new model in the ultrasonic phased array industrial imaging. In the experiment, ultrasonic phased array realized dynamic focusing and the high speed scan by ultrasonic array transducer of various array time delays to get flexible controllable synthesis beam composed signals that received by 32 phased array elements . The results indicate that in the model it greatly reduces the signal sampling frequency and improves the signal-to-noise ratio, frequency resolution at the same of the beam focusing and steering flexible.

Abstract: The infrared starter is usually used to measure the artillery’s muzzle velocity, but due to the continued firelight near the muzzle produced by the continuous occurrence of the high rate of fire artillery projectile , so that the misjudgment and the Missing are easily produced by the infrared sensor . Continuous wave radar can effectively overcome the impact of the fire, but the detection accuracy of the leaving time is greatly affected echo because of the flame noise. Therefore the noise reduction of echo signal is an important step about the detection of the leaving time. For this problem, a noise reduction algorithm based on the minimum statistical noise estimation is proposed in this paper by the analysis of the echo signal. The noise of continuous muzzle flame is effectively reduced by the algorithm. It is verified correct and feasible by the processing of the measured signal. It lays the foundation for the measure of the artillery’s muzzle velocity and the engineering realization of muzzle velocity measurement.

Abstract: A kind of test bench of electric power steering system for electric bus was designed. The spiral spring was assembled as load equipment. The measure and control software is based on virtual instrument technology. The test bench has manual and electric powered input modes. Test results show that the test bench can verify the control strategies and detect the performance of the EPS prototype of electric bus.

Abstract: For a long time, the monitor and maintain of navy Vessels equipment is based on the traditional maintain theories and plan maintain. But with the development of electronically and digitization, this kind of traditional mode is more and more hard to satisfy the need of equipment, and restrict the formation and exaltation of troops fighting strength. Currently the technologies of fault prognostics and integrated health management are becoming regarded, especially on many Vessels equipment systems. There are many factors that influence the equipment environment safety, and Oil mist concentration is one of the important factors. So it is very critical to monitor oil mist concentration accurately and quickly. The paper designed a method to carry on the sampling of the air and get the original data. And forecasting the variety of oil mist concentration with grey model, it opens the air decontamination device before attaining the limited value. The calculation shows that the mode is effective, convenient, and has upper fitting precision.

Abstract: Based on modern measure technology, wavelet transform and neural networks, the system of diesel fuel fault diagnosis is designed. Wavelet packet power and RBF networks are combined together to diagnose the fuel oil system. The master system is developed with Visual C++ and the slave system is designed based on 89C52. The two systems communicate via the RS-232 serial communication. The system is applied in practice and performs well.

Abstract: For recent decades, especially with the launch of international commercial satellites carrying high-precision sensors, land use dynamic monitoring techniques based on high-resolution remote sensing imagery have undergone a phase of rapid development of key techniques applied in many aspects vastly. This paper is focused on the technological research and procedure of these key techniques, including the process of multi-temporal images, the information classification and feature extraction method, and also the analysis of classified result and driving factors influencing mutual conversion between land classes. Considering the representative meaning as its typicality in China, Yangzhou urban area was regarded as the study zone with multi-temporal images of three periods in the year of 1988, 2002 and 2007. During the procedure of classifying, object-oriented method was applied to e36xtract features from different multi-temporal imagery. Through comparative analysis, it was demonstrated that residential area expanded rapidly especially from 2002 to 2007 and area of the arable and other kinds of land cover reduced considerably. Finally, it is concluded that multiple driving forces affected the land use/change and multivariable linear regression model was used to explore the primary and secondary forces.

Abstract: The simulation model based on MATLAB/Simulink was built for the controller of electric power steering system; assist characteristic is a key part of control. The ideal assist characteristic can satisfy the requirement of steering handiness and road feel. Adaptive neuro-fuzzy control was adopted to build assist characteristic simulation controller of electric power steering system. Then the simulation test was carried out. The simulation results verify the validity of the simulation controller, which creates the research basis for preliminary ascertainment of assist characteristic and further research of control strategies.

Abstract: It has been more than 60 years from people using computer technology in project management. The hardware and software technology have been developed during these 60 years. The development have promoted the information industry progress, and also changed the project management approach. But now, the traditional project management software cannot satisfy the modern management for their limitation. System integration and network based system will be the tendency that the project management software is developing in future.

Abstract: In order to improve the accuracy of fault diagnosis of engine ignition system, in this paper, adaptive mutation particle swarm optimization (AMPSO) algorithm is used to optimize the weight of BP neural network. According to the fault feature of engine ignition system, the fault diagnosis is accomplished by the optimized BP neural network. The algorithm overcomes disadvantages that slowly convergence and easy to fall into local minima of standard PSO and BP network. The simulation results show that the method gains good classification result and has a certain practicality.

Abstract: This paper focuses on airborne oxygen-making system shortcomings of oxygen sensor characteristic drift in, proposes a method of fault diagnosis. Oxygen sensor with a Wavelet packet analysis of feature extraction, based on wavelet neural network method to determine whether the sensor has failed, and sensor to detect hardware and software design are given.