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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.

5 radial heat exchange wells were designed, and the different angle drilling, drilling pipe, and grouting backfill construction technology was studied. In addition, the heat transfer performance of the buried radial heat exchange wells was tested. The results show that, design of pipe equipment is feasible, construction is convenient, and the ratio of backfill material is reasonable; the heat transfer performance of 90 °buried tube is the best. The smaller the angle with the ground heat exchanger, the greater the heat exchange performance is affected by the surface temperature.

To improve the axial compression mechanical properties of the EPS particle-EPS board composite insulation wallboard, added fiber web at different levels of it, got the best arrangement to improve the performance of axial compression through the test.

In this paper, by establishing the finite element model to study the dynamic characteristics of rigid frame single-rib arch bridge. By respectively changing structural parameters of the span ratios, and the compressive stiffness of arch, and the bending stiffness of arch, and the bending stiffness of bridge girder, and the layout of boom to find out the regularity of the structure on lateral stiffness, and vertical stiffness, and torsional stiffness as well as dynamic properties, it come out the results of that lateral stiffness of the structure is weaker, and increasing the span ratios and the compressive strength of arch are conducive to the improvement of the overall stiffness, and improving the bending strength of arch and layout of boom are less effect on the overall stiffness and mode shape.

An approach is presented to study the nonlinear forced vibration of a stiffened plate. The 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. Assuming the displacement of the stiffened plate, Lagrange equation and modal superposition method are used to derive the dynamic equilibrium equations of the stiffened plate according to energy of the system. A stiffened plate with four clamped edges subjected to harmonic excitation is studied by means of the method of multiple scales; the first approximation solutions of the double-modal motion of the system are obtained. Numerical examples for different stiffened plates are presented to discuss the steady response of the primary resonance and the amplitude–frequency relationship; and some nonlinear forced vibration characteristics of the stiffened plate are obtained, which are useful for engineering design.

：On the basis of preliminary exploration, complement exploration is executed to obtain excavation seepage analysis detail parameters. According to the three-dimension finite difference method and regulating calculation method, the excavation seepage analysis of anchorage circular foundation at Huangpu bridge south and the influence of different depth rock-socketed on foundation seepage are discussed. With the experience in similar projects at home and abroad, the depth of diaphragm wall embedded in weak weathered rock is not less than 3 meters, grouting curtain wall consists of 10 meters, and the waterproof curtain outside the foundation is canceled from preliminary design. The stress, strain and water level are monitored during the excavation process, and the deformation of the supporting structure is within the control. The structure is under reasonable force and the sealing effect is obvious when the foundation is excavated. Construction practice shows that the excavation seepage analysis of anchorage circular foundation at Huangpu bridge south are consistent with engineering practice.

Based on tension-compression and bending equivalences, an equivalent single material plate is formed to substitute bridge deck of composite girder with steel fiber reinforced concrete (SFRC) and steel. Thickness and elastic modulus of the equivalent plate are then formulated. After three dimensional finite-element analyses of the bridge deck, in terms of shell element membrane effect and girder flexion-torsion theory, combined with compatibility of deformation, single material shell element stress is restored to stresses on SFRC plate and steel plate separately; shear force distribution on shear keys between SFRC and steel is analyzed.

Two 1:2 reduced-scale model tests with different types of shear connectors are conducted to study the mechanical properties of shear connectors for a composite beam un- der complex stress conditions. The strain of the shear connector and relative slipping on the steel-concrete interface of the rigid shear connector model and flexible shear connector model under the same boundary conditions is measured. Responses of two types of shear con- nectors under three different load cases are compared. The test results show that the ultimate bearing capacity of concrete is the key factor of relative slipping on the steel-concrete inter- face, and differences between rigid and flexible shear connectors are large.

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.

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.