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	Geological events and Pliocene climate fluctuations explain the phylogeographical pattern of the cold water fish Rhynchocypris oxycephalus (Cypriniformes: Cyprinidae) in China 期刊论文 OAI收割 BMC EVOLUTIONARY BIOLOGY, 2014, 卷号: 14, 期号: 14 作者: Yu, Dan; Chen, Ming; Tang, Qiongying; Li, Xiaojuan; Liu, Huanzhang 收藏 \| 浏览/下载：32/0 \| 提交时间：2015/01/20 Phylogeography Cryptic subspecies Three steps Neogene climate fluctuations Conservation
	Scene matching based on directional keylines and polar transform (EI CONFERENCE) 会议论文 OAI收割 2010 IEEE 10th International Conference on Signal Processing, ICSP2010, October 24, 2010 - October 28, 2010, Beijing, China 作者: Wang Y.; Wang Y. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 Scene matching under complex background is a priority and difficulty in the field of computer vision it has the characteristics of rotation and scaling invariance commonly used in matching real-time collected images and photos for navigation. Scene matching techniques are faced with complex natural scenes anti-light and anti-slight-distortion the image distortion exist applicable for complex scene matching. The project has a new idea: combining the keylines with the vectors description based on polar image translation such as light and utilize the rotation-scale-invariance vectors to describe the extracted keylines change of gray levels this method includes three steps: keylines extraction perspective description and matching. Preliminary experiments show that this keylines-based scene matching algorithm is applicable for image matching under complex background. 2010 IEEE. scaling and other differences which cause matching difficult. This paper aims to find a scene matching algorithm
	High accuracy star image locating and imaging calibration for star sensor technology (EI CONFERENCE) 会议论文 OAI收割 6th International Symposium on Precision Engineering Measurements and Instrumentation, August 8, 2010 - August 11, 2010, Hangzhou, China 作者: Wang Y.; Wang Y.; Wang Y.; Wang Y.; Wang Y. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 Today aircraft attitude measurement technology plays an important role in an aircraft system because it can provide orientation for aircraft in action. Lately star sensor technology used in aircraft attitude measurement has become more and more popular because of its high accuracy light weight without attitude accumulation errors and other advantages. There are three main steps for star sensor to measure aircraft attitude star image locating star identification and attitude tracking. The latter two steps are based on the accuracy of star image locating. So it's critical to make efforts to advance the accuracy of star image locating. Some imaging errors such as spherical aberration or coma aberration also have negative effect on the accuracy of star image locating of which the effect is necessarily reduced as well. At the beginning of this article the structure of star sensor hardware is introduced. Secondly three methods for star image locating are described specifically which are traditional centroid method Gauss quadric fitting method and improved Gauss quadric fitting method. Subsequently an imaging calibration method is described for the purpose of reducing the effect of imaging errors. Finally the experiment shows that the accuracy of the star sensor is 2-arc-second. 2010 SPIE.
	Small satellite laser interconnect technology based on human bionics (EI CONFERENCE) 会议论文 OAI收割 CLEO/Pacific Rim 2009 - 8th Pacific Rim Conference on Lasers and Electro-Optics, August 30, 2009 - September 3, 2009, Shanghai, China 作者: Wang J.; He X. 收藏 \| 浏览/下载：14/0 \| 提交时间：2013/03/25 A new concept of satellites laser interconnect was proposed based on the human bionics. Three steps were used to set up the optical link just as the eyes. 2009 IEEE.
	Fabrication of multilayer laminar grating with high efficiency for extreme ultraviolet (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Jin C.-S.; Zhang L.-C. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 The main goal for investigations on multilayer laminar gratings working at the EUV region is to enhance their efficiency. In this article second third we demonstrate a routine to fabricate multilayer laminar gratings with high efficiency. This routine comprises three steps: first optimizing fabricating techniques to obtain multilayer coatings with high reflectivity strictly controlling errors of multilayer grating parameters to ensure the coinciding of the optical performance with the expectation. Results demonstrate that this routine is feasible. The measured peak efficiency of -1 order at 12.8nm was 14.3%. Some related issues about efficiency curves such as wavelength separation and suppression of zero order are discussed. preparing grating substrates with ideal groove profile and low roughness by holographic recording and ion beam etching process