Applied Mechanics and Materials Vols. 325-326

Abstract: A new method of misalignment characteristic analysis, which is based on advanced empirical mode decomposition (AEMD), is presented in this paper. At first the vibration signals of a rotor system with different misalignments is collected separately. Then the multicomponent signal x (t) is decomposed into a number of the so-called intrinsic mode functions (IMFs) by use of AEMD respectively. For these IMFs the wavelet method is used to extract the interesting features. It is found that the IMF2 contains the interesting misalignment character. Additionally the experimental results substantiate that the proposed method for misalignment analysis can identify the varying trend of misalignment fault clearly.

Abstract: With the explosion of information and the diversify of modern culture, the communication of information have changed a lot, especially the visualization design of data .This paper analyzed the status of Data Visualization in order to expound the significance of Data Visualization and the applications trend .

Abstract: Image matching is a key a key technology to be solved in the fields of digital photogrammetry and computer vision. Matching based on points matching is most widely used now. How to locate the right feature points is vital. Only accurate feature points can make right matching results. The paper introduces a method of 3-D Harris detector. The two steps matching have been done in our works. The results of experiments show that the 3-D Harris detector is accuracy and efficient.

Abstract: Shadowgraph is an important method to obtain the flight characteristics of high-speed object, such as attitude and speed etc. To get the contour information of objects and coordinates of feature points from shadowgraph are the precondition of characteristics analysis. Current digital shadowgraph system composed of CCD camera and pulsed laser source is widely used, but still lack of the corresponding method in image processing. Therefore, the selection of an effective processing method in order to ensure high effectiveness and accuracy of image data interpretation is an urgent need to be solved. According to the features of shadowgraph, a processing method to realize the contour extraction of high-speed object by adaptive threshold segmentation is proposed based on median filtering in this paper, and verified with the OpenCV in VC environment, the identification process of the feature points are recognized. The result indicates that by using this method, contours of high-speed objects can be detected nicely, to combine relevant algorithm, the pixel coordinates of feature points such as the center of mass can be recognized accurately.

Abstract: Based on the palm bio-impedance spectroscopy (BIS) features, this paper suggests a kind of feature extraction algorithm suitable for the palm BIS. The palm BIS under the multi-frequency is measured , a wavelet transform with the characteristics of multi-resolution analysis is selected; each set of palm BIS data is discomposed ; the feature subset of wavelet coefficients with the different dimensions is extracted ;and then the support vector machine is used to carry out the matching judgment . The testing results indicate that the correct rate of the palm BIS feature extraction algorithm based on the wavelet transform is 91%, and its error rate is 9% ,whereby testifying that this algorithm is of an excellent robustness.

Abstract: In view of the complexity of twin screw and melt pump tandem extrusion systems, the identification of the dynamic characteristics of these systems was performed by using MATLAB and state subspace method. Three input one output model was obtained and the controllability and observability of the system was identified by MATLAB. The fitting degree of simulated and actual melt pressure curve increased with increasing the output variables, which indicated that the tandem extrusion system was an interrelated coupled nonlinear system.

Abstract: A novel and efficient speckle noise reduction algorithm based on wavelet transform by cycle spinning for removing speckle of unknown variance and minimizing the effect of pseudo-Gibbs phenomena from Synthetic Aperture Radar (SAR) images is proposed. Therefore, we show that the sub-band decompositions of logarithmically transformed SAR images. Then, we process and reconstruct multi-resolution wavelet coefficients by wavelet-threshold using cycle spinning, a technique estimating the true images as the linear average of individual estimates derived from wavelet thresholded translated versions of the noise images. Experimental results show that the proposed de-noising algorithm is possible to achieve an excellent balance between suppresses speckle effectively and weaken as many image Gibbs phenomena as possible. Quantitative and qualitative comparisons of the results obtained by the new method with the results achieved from the other speckle noise reduction techniques demonstrate its higher performance for speckle reduction in SAR images.

Abstract: For the purpose of improving the real-time performance of the SIFT algorithm, an image matching algorithm based on SUSAN-SIFT algorithm is proposed in this paper. Use SUSAN algorithm in the detecting feature points part of the SIFT algorithm, avoiding the time-consuming down-sampling and Gaussian convolution of the algorithm, and remove the feature points of the unstable and low-contrast by the methods of interpolated estimate and the principal curvatures, and then use the SIFT algorithm to achieve the parts of describing the feature points and images matching. experimental verification: the SUSAN-SIFT algorithm has more fast calculation speed than SIFT algorithm ensuring the accuracy at the same time.

Abstract: Naive Bayesian classifier (NBC) is a simple and effective classification model, but its condition independence assumption is often violated in reality and makes it perform poorly. In our study, we attempt to improve the NBC model through the way of attribute selection based on rough set. The main idea of the improvement model is to select a closest approximate independent attributes subset and relax the assumption of independence. Through the experimental comparison and analysis on the UCI datasets, the model is proved effective.

Abstract: Based on the current studies on visual comfort of stereo images, we studied the brightness, hue and saturation factors impact the comfort of stereo images combining the characters of human visual system (HVS) quantitatively. According to the improved limit method and subjective assessment experiments, we defined the comfortable matching and difference map of brightness, hue, saturation, and verified their universal applicability. The accurate rate can reach 90%.