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	A shape context based Hausdorff similarity measure in image matching 会议论文 OAI收割 5th International Symposium on Photoelectronic Detection and Imaging (ISPDI) - Infrared Imaging and Applications, Beijing, June 25-27, 2013 作者: Ma TL(马天磊); Liu YP(刘云鹏); Shi ZL(史泽林); Yin J(尹健) 收藏 \| 浏览/下载：37/0 \| 提交时间：2013/12/26 The traditional Hausdorff measure, which uses Euclidean distance metric (L2 norm) to define the distance between coordinates of any two points, has poor performance in the presence of the rotation and scale change although it is robust to the noise and occlusion. To address the problem, we define a novel similarity function including two parts in this paper. The first part is Hausdorff distance between shapes which is calculated by exploiting shape context that is rotation and scale invariant as the distance metric. The second part is the cost of matching between centroids. Unlike the traditional method, we use the centroid as reference point to obtain its shape context that embodies global information of the shape. Experiment results demonstrate that the function value between shapes is rotation and scale invariant and the matching accuracy of our algorithm is higher than that of previously proposed algorithm on the MEPG-7 database.
	Effects of experimental warming on stomatal traits in leaves of maize (Zea may L.) 期刊论文 OAI收割 ECOLOGY AND EVOLUTION, 2013, 卷号: 3, 期号: 9, 页码: 3095-3111 Zheng, YP; Xu, M; Hou, RX; Shen, RC; Qiu, S; Ouyang, Z 收藏 \| 浏览/下载：58/0 \| 提交时间：2013/11/12 Elevated temperature maize (Zea may L.) Ripley's K-function spatial distribution pattern stomatal aperture size and shape stomatal frequency
	Effects of experimental warming on stomatal traits in leaves of maize (Zea may L.) SCI/SSCI论文 OAI收割 2013 作者: Xu M.; Qiu S. 收藏 \| 浏览/下载：92/0 \| 提交时间：2014/12/24 Elevated temperature maize (Zea may L.) Ripley's K-function spatial distribution pattern stomatal aperture size and shape stomatal frequency radiation use efficiency arabidopsis-thaliana atmospheric co2 elevated co2 c-4 photosynthesis leaf surface drought susceptibility adaptive significance perennial grasses abscisic-acid
	Geometrical modulation transfer function of different active pixel of CMOS APS (EI CONFERENCE) 会议论文 OAI收割 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 作者: Li J.; Liu J.; Liu J.; Liu J.; Li J. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 The geometrical Modulation Transfer Function (MTF) of CMOS APS (active pixel sensor) is analyzed in this paper. Advanced APS have been designed and fabricated where different pixel shapes such as square rectangle and L shape were placed because the amplifier circuit and other function circuits inter pixel of APS take up some pixel area. MTF is an important figure of merit in focal plane array imaging sensors. Research on analyzing the MTF for the proper pixel shape is currently in progress for a centroidal configuration of a target position. MTF will give us a more complete understanding of the tradeoffs opposed by the different pixel designs and by the signal processing conditions. Based on image sensor sampling and reconstructing model the MTF expression of any active pixel shape has been deduced in this paper. According to actual pixel shape three different active area pixels were analyzed they were square rectangle and L shape their Fill Factor (FF) is 30% 44% and 55% respectively. Results of simulation experiments indicate that different pixel geometrical characteristics contribute significantly to the figures of their MTF. Different geometrical shape of active sensitive area of pixel and different station in pixel would influence MTF figures. The analysis results are important in designing better APS pixel and more important in analyzing imaging system performance of APS subpixel precision system.
	Active pixel sensor geometrical characteristic effects on star image subdivided locating accuracy for star tracker (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: Liu J.; Liu J.; Liu J.; Li J.; Li J. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 Active pixel sensor (APS) star tracker becomes an investigated hotspot because of its technical advantages. And centroid algorithm is a subpixel method proper to star position calculation because of its high accuracy and simplicity. When centroid algorithm is applied on APS star tracker APS pixel geometrical characteristics might effect on star image position accuracy. Because the amplifier circuit and other function circuits inter pixel of APS take up some pixel area the Fill Factor is less than 100%. Moreover the active sensitive area has a certain geometrical shape such as square rectangle and L shape. The Fill Factor of pixel influences on star image subdivided locating accuracy when using centioid algorithm. In this paper we have analyzed all pixel geometrical characteristics influence on the star position accuracy. From simulation experiments we can conclude that Fill factor and pixel geometric shape influence on star position accuracy. The star locating error increased when Fill Factor decreased and different geometrical shape of active sensitive area of pixel can make different influence on star location accuracy the symmetrical sensitive area in x or y axis have symmetrical location error in the same axis.