Applied Mechanics and Materials Vols. 644-650

Abstract: Retro-reflected wave power of cat-eye target is an important factor for active laser detection system, which can evaluate high or low cat-eye effect of photoelectrical device. Theoretical and experimental results show that retro-reflected wave power will rapidly decline with defocusing distance increases and the decline more notable in negative defocusing condition.

Abstract: To improve the reliability, real-time performance and maintainability of navigation system, an optical-mechanical-electrical integrative design method of the fiber optic gyro inertial navigation /beidou/odometer integrated navigation system is proposed. Based on the basic working principle of the integrated navigation system, design of system structure and signal connection are implemented. In the integrated navigation system, all-fixed-structure, instrument and system integrative design and modularization design are used. At last, the integrated navigation system is developed, north seeking test and vehicle test are carried out to demonstrate the validity of the referred system design.

Abstract: The design method of large-scale intelligent traffic monitoring system is studied. Traffic monitoring methods have become the core problem of intelligent transportation research field. To this end, this paper proposes an intelligent traffic monitoring method based on clustering RBF neural network algorithm. Fourier coefficient normalization method is used to extract the feature of traffic state, to be as the basis for intelligent traffic monitoring. Using clustering RBF neural network algorithm identify the traffic state effectively, thus to complete the state recognition of intelligent traffic monitoring. Experimental results show that the proposed algorithm performed in intelligent traffic monitoring, can greatly improve the accuracy of monitoring.

Abstract: The automatic monitoring system for coal mining subsidence is introduced from the main research contents, composition of system, construction of system, etc. in this paper. The system is based on GNSS CORS technology, GIS technology, computer network communication technology, mobile PDA technology, modern measurement data processing technology. It takes GNSS reference station subsystem, GNSS CORS monitoring station subsystem, data monitoring center subsystem, subsystem of real-time data acquisition terminal and subsystem of communication as core modules. Equipment monitoring, data collecting and transmitting, data processing and analyzing ,subsidence predicting and early warning, mining damage evaluating are built up into a automatic monitoring system for coal mining subsidence. This system can provide decision-making basis for mine safety mining and geological environmental governance.

Abstract: A master oscillator power amplifier (MOPA) structured double-clad Yb-doped pulse fiber laser was presented, center wavelength of 1064nm, pulse width adjustable between 53ns-147ns, repetition rate adjustable between 50kHz-200kHz. Through external cavity frequency-doubling with a KTP crystal, the green light visibly of 532nm by fundamental beam of 1064nm was obtained. The highest frequency doubling efficiency was 16.2% when repetition rate of 50kHz and pulse width of 53ns. Relation of fundamental input beam and frequency-doubling output beam were studied through change the pulse parameters of fundamental beam and length of KTP crystal, the influences of fiber laser frequency doubling efficiency were analyzed.

Abstract: In order to achieve the wireless operation of the data collected and system monitoring in the weighing equipment, a wireless weighing system design was proposed. This scheme combines with the weighing control technology and the wireless communications technology. The weighing system includes the pressure sensor, the signal processing module, the microprocessors, wireless data transceiver module, the infrared module, the memory module, the display module and the control module. Based on the experiment of ten different targets ranged from 5kg to 50kg, the wireless weighing system was measured and analyzed. Experimental results show that the maximum error rate of the wireless weighing system is 0.2%, and wireless transmission distance reaches two hundred meters.

Abstract: In this paper, we did the analysis of the gyro error using Allan variance method, static output data using a three-axis gyroscope of the global first integrated six-axis motion processing components MPU6050. Experimental result shows that it not only improves the estimation accuracy of gyro error, but also the amount of data required is greatly reduced.

Abstract: Data transmission on sensor nodes is realized through data fusion processing, as well as software and hardware design of sensor node. Feedback process is performed on agricultural environment as it transfers to the terminal device finally. This paper has designed a kind of data fusion hue which could immediately perform pixel-level fusion processing after sensor nodes obtain information, and put forward that the data fusion algorithm (KDF) based on Kalman filtering could be applied for data fusion processing of system. Mesh network is constructed on the basis of hardware by sensor nodes based on ZigBee wireless communication protocol .Thus this overall set of intelligent monitoring and processing center which integrates user management, data analysis, and information issuing into an organic whole is designed.

Abstract: High density resistivity method have integrated resistivity method and induced polarization method. It is widely used in exploring metallic deposits, especially metallic sulfide deposits. The aim of this article is to study three-dimensional inversion and visual expression of two-dimensional profile survey data in high density resistivity. After testing computing capability and application effect of three-dimensional inversion, the results show that the change rules of resistivity can be seen more clearly. And the visual expression after three-dimensional inversion is able to help us observe the distribution characteristics of resistivity with various perspectives. These results are helpful for us to deduce distribution characteristics and special locations of geological structures. They are also helpful to do some effective geological explaining works for spatial distributions and changing rules of ore deposits.

Abstract: Several stress relaxation and creep tests of high temperature material are performed. According to the characteristics of stress relaxations and the superposition equation of diffusion and Maxwell equations of two stages, equivalent relaxation time and equivalent relaxation rate are proposed. Considering equivalent relaxation rate as the creep rate under constant stress, the relaxation-creep conversion model is built up and presented. Then the steady-state creep curve and creep rate are calculated. The results show that the numerical results are in good agreement with the experimental data. It indicates that equivalent relaxation rate can be employed for the analysis of steady-state creep rate. The conversion model and method can be used to design the creep strength and predict the life of the component at high temperature.