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浏览/检索结果: 共6条，第1-6条 帮助 限定条件 发表日期：2006     已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 Target track system design based on circular projection (EI CONFERENCE) 会议论文 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China Song H.-J.; Zhu M.; Hu S.; Shen M.-L. 收藏  |  浏览/下载：14/0  |  提交时间：2013/03/25 Template matching is the process of searching the present and the location of a reference image or an object in a scene image. Template matching is a classical problem in a scene analysis: given a reference image of an object  decide whether that object exists in a scene image under analysis  and find its location if it does. The template matching process involves cross-correlating the template with the scene image and computing a measure of similarity between them to determine the displacement. The conventional matching method used the spatial cross-correlation process which is computationally expensive. Some algorithms are proposed for this speed problem  such as pyramid algorithm  but it still can't reach the real-time for bigger model image. Moreover  the cross-correlation algorithm can't be effective when the object in the image is rotated. Therefore  the conventional algorithms can't be used for practical purpose. In this paper  an algorithm for a rotation invariant template matching method based on different value circular projection target tracking algorithm is proposed. This algorithm projects the model image as circular and gets the radius and the sum of the same radius pixel value. The sum of the same radius pixel value is invariable for the same image and the any rotated angle image. Therefore  this algorithm has the rotation invariant property. In order to improve the matching speed and get the illumination invariance  the different value method is combined with circular projection algorithm. This method computes the different value between model image radius pixel sum and the scene image radius pixel sum so that it gets the matching result. The pyramid algorithm also is been applied in order to improve the matching speed. The high speed hardware system also is been design in order to meet the real time requirement of target tracking system. The results show that this system has the good rotate invariance and real-time property.   An improved two-dimensional entropy method for star trail tracing in deep sky (EI CONFERENCE) 会议论文 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China Yao Z.-J.; Wang Y.-J.; Han Q.-L. 收藏  |  浏览/下载：15/0  |  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.   Method for computer-aided alignment of complex optical system (EI CONFERENCE) 会议论文 2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 2, 2005 - November 5, 2005, Zian, China Yang X.; Han C.; Yu J. 收藏  |  浏览/下载：19/0  |  提交时间：2013/03/25 For making complex optical system meet the design requirement  such as the space camera used in remote sensing and UVX lithophotography  especially for off-axis all-reflecting optical system  alignment technology is so necessary. In this paper  a method is presented. Based on the ideas of linearity instead of non-linearity and difference quotient instead of differential quotient  a mathematical model for computer-aided alignment is proposed. This model included the characteristics of the optical system  wavefront difference of its exit pupil and its misalignment of the misaligned optical system. Then comparing self-compiled software with alignment package of CODE V  as a result  this self-compiled software is much more valid than alignment package of CODE V. For a large aperture  long focal length and off-axis three-mirror optical system  computer-aided alignment is successful. Finally  the wavefront error of the middle field is 0.094 waves RMS and the wavefront error of +0.7 field is 0.106 waves RMS and the wavefront error of -0.7 field is 0.125 waves RMS at =632.8nm are obtained.   Design of GPS/INS integrated navigation system based on multisensor information fusion (EI CONFERENCE) 会议论文 6th World Congress on Intelligent Control and Automation, WCICA 2006, June 21, 2006 - June 23, 2006, Dalian, China Chunmei H.; Yantao T.; Wanxin S.; Mao L. 收藏  |  浏览/下载：24/0  |  提交时间：2013/03/25 Two kinds of design methods of GPS/INS integrated navigation system are presented  that is GPS/INS integrative system and integrated navigation system based on information fusion. By analyzing mathematics model of the first system error  we found that inertia velocity error would cause code loop track error. Consequently  the pseudo range meterage error is interrelated with inertia velocity error  which is complex to calculate. If this relativity is ignored in the state equation and observation equation of this system  it must affect the estimated precision of the kalman filter and maybe the system is unstable. Therefore  the second integrated navigation method is introduced. It adopts information fusion  federal kalman filter and covariance. And consider the above pertinence to analyze the navigation performance of the integration system. Then it gives the flow of federal kalman filter algorithm. By analyzing  the conclusion is that velocity error of integrated navigation system drops from 0.5m/s to below 0.05m/s  and improves the precision and reliability of the navigation system effectively  well continuity and real-time capability. It provides an effective way for data analysis and process of fusion navigation system. 2006 IEEE.   Abrupt sensor fault diagnosis based on wavelet network (EI CONFERENCE) 会议论文 2006 IEEE International Conference on Information Acquisition, ICIA 2006, August 20, 2006 - August 23, 2006, Weihai, Shandong, China Zhang H.; Chen T.; Li W. 收藏  |  浏览/下载：11/0  |  提交时间：2013/03/25 The possible faults of a sensor may be classified as abrupt (sudden) faults and incipient (slowly developing) faults. This paper focuses on the abrupt faults of a sensor. Due to the limited number of scales  a single wavelet amplitude map has not enough scales to describe all details of the signal. The sampling grid in the scale direction is rather sparse  Some of the fault information will be leaked under such sparse grid. To make up for the deficiency of scalar orthogonal wavelet transform in the application of abrupt fault diagnosis  multiwavelet packets transform was introduced into the field of abrupt fault diagnosis. The distribution differences of the signal energy on decomposed multiwavelet scales of the signal before and after the fault occurring are extracted as the fault feature and used as the input of multi-dimensional wavelet network. A new model-free diagnostic method for isolating abrupt sensor faults is developed based on a proposed algorithm of multi-dimensional wavelet network constructing. The method has been proved to be quite effective in the detection of sensor abrupt fault. 2006 IEEE.   Thermodynamic properties of mixed-spin chains in magnetic field by the transfer matrix method 期刊论文 Journal of Magnetism and Magnetic Materials, 2006, 卷号: 305, 期号: 1, 页码: 253-258 H. H. Fu; K. L. Yao; Z. L. Liu 收藏  |  浏览/下载：13/0  |  提交时间：2012/04/13 thermodynamics  molecule-based ferrimagnetics  transfer matrix method  molecule-based ferrimagnets  numerical-calculations  renormalization-group  system  model