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An approach is presented to investigate the nonlinear vibration of stiffened plates. A stiffened plate is divided into one plate and some stiffeners, with the plate considered to be geometrically nonlinear, and the stiffeners taken as geometrically nonlinear Euler beams. Lagrange equation and modal superposition method are used to derive the dynamic equilibrium equations of the stiffened plate according to the energy of the system. Besides, the effect caused by boundary movement is transformed into equivalent excitations. The primary parametric resonance–primary resonance of the stiffened plate is studied by using homotopy analysis method. Numerical examples for stiffened plates with different thicknesses of the plates are presented to discuss the amplitude–frequency and amplitude–excitation relationship of the primary parametric resonance–primary resonance. In addition, the analysis on how the damping coefficients and the transverse excitations influence amplitude–frequency curves is also carried out. Some nonlinear vibration characteristics of stiffened plates are obtained, which are useful for engineering design.

The problem of form-finding for the suspended cable is actually the problem of determining all key points coordinates on main cable, which are by equilibrium relation on the horizontal force, main cable sagitta and lifting point force under the precondition of determining the endpoints boundary conditions of cable segment. According from the static equilibrium relationship of cable element, based on the analysis of its analytical solution process, in this paper, the cable elements are divided into two types in accordance withthe vertical distribution load along the arc length and along the string length , the corresponding shape curve of cable element is the parabola and the catenary, and with parabolic results as its initial value for the iteration of nonlinear solution, then cable element eventually converge for the catenary. And based on the exact coordinates results ,the calculation method of the length without stress is presented,and compiled corresponding computational procedures. By comparing the results of form-finding and the cable-length in non-stress according to program compiled and the results from the finite element software and the measured value of Aizhai suspension bridge, compared with the nonlinear finite element method,it confirmed the method requireing smaller dividing element density, the convergence speed is quicker and the results can ensure the precision.

Making use the prior knowledge that higher order cumulant and wavlet transformation methods are combined, which is used in the multi-dim-small target detection with the Gaussian noise and natural background. In this paper, a method of magnifying image based on two dimension discrete wavelet is introduced. Comparing with traditional interpolation methods, it not only enhanced resolution of the aero-image, but maintained the detail character of the image. Experiment results have shown that it is good method for enhancing aero-image. The same aerial image is magnified with above-mentioned wavelet-based algorithms, conventional bilinear interpolation and tri-spline sampling interpolation algorithm separately. The values of mean gradient on three graphs are calculated using three approach, they are 6.31, 7.43 and 8.45. In accordance with the result, the value of the magnified image by this method is largest.

This paper introduces a saving-energy controlling method of water-circling pump. It is a method that traditional PID control combined temperature fuzzy-PID and PWM. The enactment in advance include that turn frequency, turn delay and the value of floor and upper limit difference in temperature pulse. The pump's running-frequency is adjusted by saving-energy controlling tank through PID arithmetic bases on difference temperature between input pipe and output pipe. When it is the moment that the running-frequency under the turn-frequency and it is turn-delay, the method of PWM is adopted. When it is the moment that the running-frequency up the turn-frequency, it will be into the method of fuzzy-PID adjusting. It will be truth that heating temperature will be controlled through out-temperature because the application of PWM technology. This method will save energy of pump above 30 percent, as the user's requirement is met.

A novel two-dimensional (2-D) adaptive filtering algorithm to enhance 2-D signals of small spatial extent embedded in white Gaussian noise and a variety of outstanding modern digital signal processing methods are combined in background segmentation. The coefficients of the adaptive filter converge to a special 2-D slice of the fourth-order cumulant function of the input signal. The proposed algorithm is called the 2-D cumulant adaptive enhancer (2DCAE). And the methods in background segmentation is combining the wavelet energy transformation, data integration and threshold segmentation.