Applied Mechanics and Materials Vols. 347-350

Abstract: a new method of random error separation based on wavelet transform and the frequency bands character of measurement data is proposed. Approximates the random error with the detail components of the wavelet decomposition, determines the optimal decomposition level on the frequency intervals between the random errors and other components, and finally gets the random error by reconstructing all the detail components. The method is simply and efficient, avoids the indirect error with modeling and indirect methods, and computer simulation proves the robustness of the separation results.

Abstract: a virtual prototype program of hydraulic Stewart force feedback master-slave system is developed to solve the modeling problems when plant developing and controller design. The following work is done based on the Stewart manipulator simulation program built in Matlab/SimMechanics platform: 1. Master/slave force feedback control framework is built based on the relationship between force on cylinders and upper platform.; 2. A new Stewart platform with load force model on the upper platform hydraulic servo system is built as the slave hand. The validity of the functions is verified by simulation experiment.

Abstract: According to the development of personnel positioning system, with the use of data storage technology, multithreading technology, information buffer technology and TCP communication technology, this simulator can not only simulate multidevice reporting to multiuser, but also realize pressure test for the upper software by adjusting the amount of reporting data, therefore, the software problems can be found in advance and solved in time.

Abstract: Because of the special optical underwater imaging environment, the contrast and quality of images are affected severely, causing it difficult to extract objects from underwater images. An adaptive underwater object extraction method based on the saliency maps is proposed in this paper. Firstly, preprocessing method is utilized to improve the color contrast and quality. Then multi-scale image features are combined into a single topographical saliency map. The most salient image location and primary object are directed by the saliency map. By calculating the Bhattacharyya distance of salient features between the primary object and background, the adaptive weights of conspicuity maps can be obtained, as well more accurate object can be extracted from the fuzzy images. Experiment results show that the proposed method can not only detect the objects effectively but also extract more accurate object areas. It has a better performance compared with other algorithms.

Abstract: With the development of network application, network security is facing greater pressure. Based on the characteristics of intrusion detection in the wireless network of the Ad hoc working group, the article introduces the game theory, proposes a game model of network security, concluds the Nash equilibrium in the stage game, repeats game, the pareto Nash equilibrium, more attack both income and payment, so that they get the best choice.