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	The impact of various crack geometrical parameters on stress field over tip under different mixed loading conditions and inclination angles 期刊论文 OAI收割 THEORETICAL AND APPLIED FRACTURE MECHANICS, 2019, 卷号: 102, 期号: -, 页码: 239-254 作者: Wang, Luyu; Chen, Weizhong; Tan, Xuyan; Yang, Jianping \| 收藏 \| 浏览/下载：15/0 \| 提交时间：2020/04/08 Crack tip Stress distribution Stress intensity factor Complex loading Geometrical parameter
	The geometric factor of high energy protons detector on FY-3 satellite 期刊论文 OAI收割 SCIENCE CHINA-EARTH SCIENCES, 2014, 卷号: 57, 期号: 10, 页码: 2558-2566 作者: Zhang ShenYi; Zhang XianGuo; Wang ChuiQin; Shen GuoHong; Jin Tao 收藏 \| 浏览/下载：29/0 \| 提交时间：2015/09/22 geometrical factor response function particle radiation space detection FY-3
	Analysis of spectrum narrowing of diode laser bar (EI CONFERENCE) 会议论文 OAI收割 Semiconductor Lasers and Applications III, November 12, 2007 - November 13, 2007, Beijing, China 作者: Liu Y.; Wang L.; Wang L.; Wang L.; Liu Y. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 Laser diode bar (LDB) are used increasingly often for many applications but spectral bandwidth of LDB are generally approximately 2-4nm far too wide for many demanding applications e.g. spin-exchange optical pumping terahertz generation and lidar. External-cavity feedback can improve the spectral properties of LD or LDB. However spectrum narrowing of LDB is more difficult than that of LD. Bar curvature (i.e. "smile") produced in the manufacturing process affects the spectrum narrowing greatly. By geometrical optics approach and ORIGIN software smile which can be corrected by plano-convex cylindrical lens is simulated and the result is in good agreement with experiment. The selection of grating which is also a critical factor of spectrum narrowing will be stated. Finally an external cavity consisting of fast axis collimator two plano-convex cylindrical lens and a diffraction grating is used. The scheme is implemented on a 19-element LDB and yields 3-fold reduction in spectral linewidth under the situation that all optical elements in the system which are not optimized. Further we use a slit in the experiment and analyze the spectrum narrowing of each element in LDB.
	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：25/0 \| 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. 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.