As a kind of structure commonly used in satellite, carbon fiber composite honeycomb sandwich panels are vulnerable to various kinds of damage, especially low-velocity impact damage in the process of using. In this paper, an impact monitoring system based on Fiber Bragg Grating (FBG) sensor is constructed. The frequency domain information of the signal can be obtained by Fourier transform. Monitoring results of different impact points show that the natural frequency of structure is 110Hz and 380Hz, which amplitude of different natural frequency is changed with position of impact point. The energy status of impact response signal can be obtained by wavelet packet analysis. The monitoring results of the same impact point shows that the change of the sensor signal is obvious in thirteenth order and energy size is related to the distance and angle between the impact point and sensor. 1,2

Microseismic will produce when rock mass break. The occurrence of microseismic monitoring has close relationship to the energy release and crack's evolution in the rock mass. Therefore the microseismic monitoring can be used to predict the future rupture of the rock mass. MS location is the base of this prediction. The method of solving locating equation and the stability of answer are the key matter of microseismic monitoring applications in engineering fields. This paper uses Gauss-Newton iterative method to solve locating equation in order to advancing the precision and stability of answer and reducing the calculation workload. Based on the optimization toolbox of Matlab, the non-linear locating equations are solved and the visible locating results of microseismic are achieved.

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We developed a new sensing technology for wind velocity and short/long wave radiation fluxes (Globe radio-anemometer). The technology is on the basis of the heat budget equations of three compact globe thermometers (GT), namely; a black GT (BGT), a white GT (WGT), and a black GT with a heat source inside (BGTH). The globe anemometer uses BGT and BGTH, and the globe radiometer does BGT and WGT. Three GTs used are 12 mm in diameter and 0.3 mm in thickness, much smaller than the standard GT. The root mean square of the error of the sensors were 0.24 m s -1 for wind velocity, 21.3 W m -2 for short wave radiation flux, and 12.3 W m -2 for long wave radiation flux with 1-minute-averaged data.