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Considering the advantage of optic fiber, a methods of measuring Cr (VI) based on absorption spectrum through plastic fiber is introduced, which includes structure of measurement, experiment process, spectrum signal process. After signal processing based on low-pass filtering and non-linear fitting, five concentrations of Cr (VI) can be differed easily and the peak values of spectrum corresponding to five concentrations accord with the Longbow Bill's law . In this way, the measurement concentration can limit down to 0. 0.0660 μg/ml.

Considering the approximation between Gaussian function and spectrum, Gaussian function is utilized to simulate the spectrum of optical fiber sensor array sensitive to four heavy metal ions. The division of superimposed spectrum in measurement by optical fiber sensor array and the analysis of relative error are simulated by Matlab software. From the simulation, it is known that the superposition error of spectrum caused by interference between four ions in films sensitive to heavy metal ions can be reduced with corresponding arithmetic, which provides good theoretical foundation for preparation of optical fiber sensor array and signals processing of spectrum.

Two kind of frequency modulator to produce multi-frequency light impulse array and a kind of measurement system for light addressable potentiometric sensor (LAPS) array are introduced based on micro-lens and frequency modulator disk. Simulation of FFT is used to analyze the available photocurrent signals of LAPS array with MATLAB. According the simulation spectrum, the corresponding photocurrent signals of light impulse with different frequencies are able to resolve. When the duty ratio is larger than or equal to 30%,the construction of the frequency modulator can be simplified, which further prove that LAPS array with multi-frequency light impulses is provided with reliable resolution .All of above provides enough theoretical foundation for preparation and signal processing of LAPS array device .

A de-couple control method with information feedback from other control channel and a method with double control loops were present for the hypersonic vehicle with non-linear, couple and lateral maneuver. The whole controller was divided into two parts: the computation of actuator which deal with control couple and design of control law which solve the problem of movement and aerodynamic couple. The time-varying controller parameter method and robust control law were present to solve the problem of quick time-varying model parameter and non-linear. Finally these two methods were analyzed contrastively; the simulation result show that these two methods present above can achieve the quick dynamic and high precise track of command. But the latter was better.

A meshless local Petrov-Galerkin method for the elastic dynamic analysis of a nonhomogeneous moderately thick plate is presented in this paper. The discretized system equation of the moderately thick plate is obtained using a locally weighted residual method. It uses a radial basis function coupled with a quadratic polynomial basis function as a trial function and a quartic spline function as a test function of the weighted residual method. The shape function has the Kronecker delta function properties, and no additional treatment to impose essential boundary conditions. In computational procedures, variations of material properties in the considered domain are modelled by adopting proper material parameters at Gauss points in integrations. Examples show that the presented method can give quite accurate results to elastic dynamic problems of the nonhomogeneous moderately thick plate.