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The physical characteristics are compared between shallow and deep water, in physics and acoustics, respectively. There is a specific sound speed profile in deep water, which is different from which in shallow water, resulting in different sound propagation law between them. In this paper, the sound field distributions are simulated under respective typical sound speed profile. The color figures of sound intensity are obtained, in which the horizontal ordinate is distance, and the vertical ordinate is depth. Then we can get some important characteristics of sound propagation. The results show that the seabed boundary is an important influence on sound propagation in shallow water, and sound propagation loss in deep water convergent zone is visibly less than which in spherical wave spreading. We can realize the remote probing using the acoustic phenomenon.

This paper discusses the Trojan horse detection methods by analysis on Portable Executable File Format through which we can get much useful information. In order to deal with the information extracted from Portable Executable file, our methods constructed a decision tree based on C5.0 decision tree algorithm. Our approach can be divided into two steps. Firstly, we extracted some features from Portable Executable file by a portable executable attribute filter. Secondly, we handled the features extracted and then construct a classifier to identify the Trojan horse. The original in this paper is the application of a more effective algorithm C5.0 to construct the decision tree.

In this paper, the cascading failures in a class of bipartite coupled map lattices are investigated. We found that for a network with given heterogeneity, international attack is much easier to trigger cascading failures than random attack. Furthermore, not only the mean node degree but also the largest eigenvalues of the network are found to relate to the size of cascading failures in the network. Therefore, this work might shed some light on the control of cascading failures in such structure of the network.

This paper analyze ultimate bearing capacity, transfer mechanism, failure process and influence of aperture, steel bar diameter, concrete rating and on elastic bearing capacity and ultimate bearing capacity of PBL shear connectors by the finite element analysis software ANSYS. This paper can provide a reference for further design of PBL shear connectors as well as push-out or pull-out test. The results show that the elasticity bearing capacity of PBL shear connectors is determined primarily by concrete while the ultimate bearing capacity is determined primarily by perforative steel bar.

Adoption of machine vision inspection and computer image processing technology, an oil-seal dimension measuring system was developed to meet the requirement of online production and real time inspection. The makeup and principle of the system were introduced, as well as its working process and design requirements were described on detailed. The technique of quadratic filtering for image preprocessing combined with the principle of three points determining a circle, point Hough transform and the least squares was employed for image processing algorithm, and high precision sub-pixel edge detection was achieved. The measuring results of experiments demonstrated that the inspection goal on 100 percents of products could be realized successfully, and with many advantages such as non-contact, on-line, real time, appropriate precision and low cost, the system can be applied widely in other production fields.

By comprehensive analysis and design optimization of barrier structure parameters, a new type of beam-and-post steel barrier was invented according to impact test condition and acceptance criteria of cross-sea bridge barrier. Full-scale impact tests and finite elements analysis were conducted to do safty evalution of the barrier. The results show that, ASI value is 1.62 for test and that is 1.67 for FEA, THIV is 30.7km/h for test and that is 31.2km/h for FEA. Working width is 0.88m for test and that is 0.62m for FEA. Occupant risk evaluation index can meet the requirements of level B and the working width can meet the requirements of level W3. Both of tracking and posture of vehicles are well. The study results above show that safety performance of cross-sea bridge barrier can meet or exceed the acceptance criteria. FEA results are consistent with Full-scale impact test, which validate the reliability of FEA. cross-sea bridge barrier can meet the highest test level for beam-and-post steel barrier, which can defend the out-of-control vehicles effectively and help to ensure the bridge safety.