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浏览/检索结果: 共6条,第1-6条 帮助

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Combining upper limits with a Bayesian approach 期刊论文  OAI收割
CHINESE PHYSICS C, 2015, 卷号: 39, 期号: 12, 页码: 123001
作者:  
Yang L(杨柳);  Zhu K(朱凯);  Zhu YS(朱永生);  Yang;  L
收藏  |  浏览/下载:13/0  |  提交时间:2016/04/18
Speech signal enhancement through wavelet domain MMSE filtering (EI CONFERENCE) 会议论文  OAI收割
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Fenghua Z.; Le Y.; Jian W.; Qiang S.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
A new speech enhancement system that combine robust signal enhancement and minimum signal distortion is proposed in this paper. The proposed method introduces frequency depended  parametric  MMSE filtering techniques that involve wavelet packets. Voice activity detection (VAD) is used to further distinguish speech from noise and help to adaptively remove noise components from color noise eruptive noisy speech  while perceptual criteria is also taken into account. Experimental results and objective quality measurement test results validate the proposed speech enhancement system and illustrate the benefit of the proposed wavelet domain MMSE filtering as an excellent speech enhancement method to provide sufficient noise reduction and good intelligibility and perceptual quality  without causing considerable signal distortion and musical background noise method. 2010 IEEE.  
Mid-frequency surface error test with a Foucault apparatus (EI CONFERENCE) 会议论文  OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, July 8, 2007 - July 12, 2007, Chengdu, China
作者:  
Li J.;  Li J.;  Xuan B.;  Li J.
收藏  |  浏览/下载:17/0  |  提交时间:2013/03/25
Testing of mid-frequency surface error is of the first importance for fast optics  especially for large aperture aspherics. Foucault test plays a dominant role for surface error inspection before the digital interferometer age  but it seems to have faded out these days because no quantitative results turn out. However  an interferometer with high resolution CCDs is either unavailable or unaccessible in the process of manufacture. As its advantages are realized and recognized for the second time  Foucault test is going back to the stage again. A new theory of calculating the contrast of the shadow pattern of Foucault test is put forward in this paper and some modifications are discussed upon the analyses of the limitation of traditional Foucault apparatus. A paraboloidal mirror was fabricated and tested by the modified Foucault apparatus whose effect has been proved to be great. The methods of controlling mid-frequency error are described in the other paper at this conference- "Multi-mode combine manufacturing technology for large aperture aspheric mirrors"1.  
Integrated intensity, orientation code and spatial information for robust tracking (EI CONFERENCE) 会议论文  OAI收割
2007 2nd IEEE Conference on Industrial Electronics and Applications, ICIEA 2007, May 23, 2007 - May 25, 2007, Harbin, China
作者:  
Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.
收藏  |  浏览/下载:28/0  |  提交时间:2013/03/25
real-time tracking is an important topic in computer vision. Conventional single cue algorithms typically fail outside limited tracking conditions. Integration of multimodal visual cues with complementary failure modes allows tracking to continue despite losing individual cues. In this paper  we combine intensity  orientation codes and special information to form a new intensity-orientation codes-special (IOS) feature to represent the target. The intensity feature is not affected by the shape variance of object and has good stability. Orientation codes matching is robust for searching object in cluttered environments even in the cases of illumination fluctuations resulting from shadowing or highlighting  etc The spatial locations of the pixels are used which allow us to take into account the spatial information which is lost in traditional histogram. Histograms of intensity  orientation codes and spatial information are employed for represent the target Mean shift algorithm is a nonparametric density estimation method. The fast and optimal mode matching can be achieved by this method. In order to reduce the compute time  we use the mean shift procedure to reach the target localization. Experiment results show that the new method can successfully cope with clutter  partial occlusions  illumination change  and target variations such as scale and rotation. The computational complexity is very low. If the size of the target is 3628 pixels  it only needs 12ms to complete the method. 2007 IEEE.  
An improved two-dimensional entropy method for star trail tracing in deep sky (EI CONFERENCE) 会议论文  OAI收割
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Wang Y.-J.;  Yao Z.-J.
收藏  |  浏览/下载:32/0  |  提交时间:2013/03/25
The trace of star trail is an important component of deep sky detection. The stars are low contrast targets  and their self-rotation will make their brightness change in cycle. Above all  the trail trace is vulnerable to the block and disturbance of other stars. Traditional one-dimensional maximum entropy thresholding algorithm is vulnerable to the noise  and the calculation of two-dimensional entropy methods is too large and takes too much time. This paper proposes an improved two-dimensional entropy threshold algorithm. We use recursion iteration method to eliminate the redundancy calculation  and reduce the size of two-dimensional histogram based on the deep sky stars characteristic  such as low contrast  fuzziness and the centralized histogram. We also combine our algorithm with the space trail trace model to forecast the star trace. Experiments results show  when the star are blocked or they turn dark  the method still can well extrapolate the star trace. Our method improves the capability of trailing the ebb and small star  and increases the precision of tracing. It is also robust to the noise  so there is a good application foreground for the method.  
A new approach for the removal of mixed noise based on wavelet transform (EI CONFERENCE) 会议论文  OAI收割
ICO20: Remote Sensing and Infrared Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Li Y.;  Li Y.;  Li Y.;  Li Y.
收藏  |  浏览/下载:38/0  |  提交时间:2013/03/25
This paper proposed a new approach for the removal of mixed noise. There are many different ways in image denoising. Donoho et al have proposed a method for image de-noising by thresholding  ambiguity is often resulted in determining the correspondence of a modulus maximum to a singularity. In the light  and indeed  we combine the merits of the two techniques to form a new approach for the removal of mixed noise. At first  the application of their method to image denoising has been extremely successful. But the method of Donoho is based on the assumption that the type of noise is only additive Gaussian noise  we used wavelet singularity detection (WSD) technique to analyze singularities of signal and noise. According to the characteristic that wavelet transform modulus maxima of impulse noise rapidly decreases as the scale increases in wavelet domain  which is not successful for impulse noise. Mallat has also presented a method for signal denoising by discriminating the noise and the signal singularities through an analysis of their wavelet transform modulus maxima (WTMM). Nevertheless  it can be accurately located with multiscale space by going through dyadic orthogonal wavelet transform and removed. Furthermore the Gaussian noise is also removed through a level-dependent thresholding algorithm  the tracing of WTMM is not just tedious procedure computationally  algorithm. The experimental results demonstrate that the proposed method can effectively detect impulse noise and remove almost all of the noise while preserve image details very well.