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Ocean front is a narrow transitional zone that the penetration of sea is obviously different between two or more waters there. It is an important feature of geophysical turbulence which plays an important role in ocean dynamics. Ocean fronts become visible on radar images because they are associated with a variable surface current which modulates the sea surface roughness and thus the backscattered radar power. This paper propose a new integrated method to extract ocean fronts based on two-dimensional Empirical Mode Decomposition (EMD), image edge detection and mathematical morphology processing. Experimental results show that this integrated method can be effective in ocean front feature extraction.

A new method based on image patch reordering for removing salt-and-pepper noise from corrupted images is presented. Firstly, the problem of salt-and-pepper noise removal can be turned into the problem of image in-painting. Then, we can use the image patch reordering method to recover the missing pixels and fulfill the salt-and-pepper noise removal. Experimental results demonstrate that the proposed method obtain much better performance in terms of both qualitative and quantitative assessment. Especially, the proposed method provides the improvement in the performance of noise suppression and detail preservation.

As the study of the dynamic response of single-layer reticulated domes under impact, Numerical models for single-layer Kiewitt-6 reticulated domes with sub steel cube column were established by the ANSYS/ LS-DYNA program and a dynamic analysis were carried out. Four failure modes for the reticulated domes were put forward according as the dynamic response and plastic deformation. The parametric analyses on the dynamic response of single-layer reticulated domes with sub steel cube column under the impact loading are carried out, by changing the impact velocity, mass of impact object, size of impact object and impact location.The effects of these parameters on the response mode of the structures are investigated, and the distribution regularity of the response modes of the structures with different parameters is explained.

The impact force is one of the most weak link of the dynamics studies of debris flow for many years. To make the structure or components are better able to suffer the impact load such as debris flow, explosions, a new debris flow dam is designed by introducing this new type model with spring. It is simulated under boulder impact by using finite element software LS-DYNA.The stress distribution, impact and displacement time history curve under typical conditions are obtained. The results show that the resist impact effect of new debris flow dam is very obvious.

The finite element modes of composite columns were built. The nonlinear analysis of the common steel column and the partial concrete encased steel composite columns were conducted. The load-displacement curves were getting. The strength of partial concrete encased steel Strengthened columns was much higher than the common steel column. Finally, Construction design suggestions and theory study of the type of partial concrete encased steel composite columns are advanced according to the results of analysis and computer simulation.

The health monitoring and diagnosis of the major engineering structure is increasingly extensive attention from all the community. In particular, for the complex large-span steel roof unloading process, it is important especially. The unloading process will cause the change of structure stiffness include the internal force redistribution. The real-time and on-line monitoring have been applied to Xining stadium of the stress in the process of unloading for the purpose of structural health assessment in the paper, so as to achieve the purpose of the early warning of the problems which may arise in construction process. At the same time, through the comparison of the finite element software ANSYS analogue simulation and the value of the actual, it is obtained for the quality problem of steel structure in the process of unloading.