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	The role of material and geometric nonlinearities and damping effects in designing mechanically tunable acoustic metamaterials 期刊论文 OAI收割 INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES, 2021, 卷号: 197, 页码: 16 作者: Ning, Shaowu; Chu, Dongyang; Jiang, Heng; Yang, Fengyuan; Liu, Zhanli \| 收藏 \| 浏览/下载：41/0 \| 提交时间：2021/05/31 Mechanically tunable acoustic metamaterials Locally resonant Bragg scattering Band gaps Material and geometrical nonlinearities Damping effect
	Study of the geometrical size effect of a fractured rock mass based on the modified blockiness evaluation method 期刊论文 OAI收割 ARABIAN JOURNAL OF GEOSCIENCES, 2018, 卷号: 11, 期号: 11, 页码: - 作者: Chen, Qingfa; Yin, Tingchang; Niu, Wenjing; Zheng, Wenshi; Liu, Junguang \| 收藏 \| 浏览/下载：136/0 \| 提交时间：2020/04/08 Fractured rock mass Modified blockiness evaluation method Geometrical size effect REV Degree of rock mass fracturing
	Geometrical scaling law for laser shock processing 期刊论文 OAI收割 JOURNAL OF APPLIED PHYSICS, 2013, 卷号: 114, 期号: 4, 页码: 043105/1-043105/9 作者: Wu XQ(吴先前); Tan QM(谈庆明); Huang CG(黄晨光) 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/09/27 Physical properties Controlling mechanism Dimensional analysis Dimensionless parameters Geometrical scaling Laser power density Laser shock processing Strengthening effect Surface residual stress
	Directional multiscale edge detection using the contourlet transform (EI CONFERENCE) 会议论文 OAI收割 2010 IEEE International Conference on Advanced Computer Control, ICACC 2010, March 27, 2010 - March 29, 2010, 445 Hoes Lane - P.O.Box 1331, Piscataway, NJ 08855-1331, United States 作者: Jin L.-X.; Han S.-L.; Zhang R.-F. 收藏 \| 浏览/下载：35/0 \| 提交时间：2013/03/25 Wavelet multiresolution analysis allows us to detect edges at different scales also to obtain other important aspects of the extracted edges. However due to the usual two-dimensional tensor product wavelet transform is not optimal for representing images. The main problem in edge detection using wavelet transform is that it can only capture point-singularities and the extracted edges are not continuous. In order to solve that problem we propose a new image edge detection method based on the contourlet transform. The directional multiresolution representation Contourlet takes advantages of the intrinsic geometrical structure of images and is appropriate for the analysis of the image edges. Using the modulus maxima detection an image edge detection method based on contourlet transform is proposed. To suppress the image noise effect on edge detection the scale multiplication in contourlet domain is also proposed. Through real images experiments the proposed edge detection method's performance for the extracted edges is analyzed and compared with other two edge detection methods. The experiment result proves that the proposed edge detection method improves over wavelet-based techniques and Canny detector and also works well for noisy images. 2010 IEEE.
	Numerical study on the influence of geometrical parameters on natural convection cooling effect of the crushed-rock revetment 期刊论文 iSwitch采集 SCIENCE IN CHINA SERIES E-TECHNOLOGICAL SCIENCES, 2009, 卷号: 52, 期号: 2, 页码: 539-545 作者: Zhang MingYi; Cheng GuoDong; Li ShuangYang 收藏 \| 浏览/下载：21/0 \| 提交时间：2019/10/08 crushed-rock revetment geometrical parameter Nu number convection pattern cooling effect
	Research on the support structure of the primary mirror of large-aperture telescope (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China Yang W.; Jingxu Z. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 Large-aperture telescope can be used in surveying battlefield researching landform searching object real-time monitoring imaging detecting and identifying spatial targets and so on. A large-aperture telescope for achieving high resolution power is designed to monitor spatial target and image in real time. Real-time monitoring plays an important role in military conflicts. The orbit parameter of object quantity geometrical shape parameter and so on can be obtained by detect spatial target. With the development of optical technology people require larger aperture in optics-electronic (OE) system. By increasing optical aperture the ability of collecting light and resolution power in the system can be enhanced. But the support structure of the primary mirror of large-aperture telescope will be a very difficult problem. With the increase of primary mirror aperture the weight of the primary mirror will become larger than before. The root mean square (rms) of the primary mirror is affected by many factors such as deadweight deformation of heat environment and so on. Due to the primary mirror of telescope is an important component of telescope system. By reducing the weight of primary mirror precision of the system is ensured. During the designing phase one can consider the supporting project of the primary mirror synthetically and analyze it roundly according to technical requirement of optical system and the effect factors. The final structural design can be reasonable. In an astronomical telescope the surface of reflector is an important part for collecting dark radiation of celestial bodies. Its surface shape will have an effect on collecting efficiency of telescope radiant energy directly. So the rms must be very high. Optical system of large aperture small wavelength and small focus can receive maximal light intensity. For ground-based optical astronomical telescope the design proposed in the paper can satisfy the requirement of the possible minimum atmosphere seeing at astronomical observatory site and exert the use efficiency of the telescope adequately. So the accuracy of the traditional surface of reflector can assure that 90% of all the light energy can be focused on within the angle diameter range of the minimum atmosphere seeing then 100% of light energy should be focused on the angle diameter range of minimum atmosphere seeing. Because the rms of mirror is very high precise surface machining and accurate the support of mirror are very important tasks during designing and manufacturing the telescope. In the paper various support techniques of a large-aperture telescope primary mirror are discussed and a 3.5 meter telescope system at the Starfire Optical Range (SOR) overviewed simply which was operated by the Directed Energy Directorate of the Air Force Research Laboratory Kirtland AFB NM USA from the ground-based O-E system for the observations of spatial target. We also analyze Theoretical elastic deformation of the Steward Observatory 2.3 meter mirror is analyzed.
	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.
	Size and geometrical effects of single-and poly-crystal metals in micro-indentation test 会议论文 OAI收割 International Symposium of Young Scholars on Mechanics and Material Engineering for Science and Experiments, Changsha, Hunan, China, 2001-8-1 作者: Wei YG(魏悦广) 收藏 \| 浏览/下载：29/0 \| 提交时间：2014/02/14 Micro-indentation test size effect geometrical effect length parameter