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	Investigating Steel Honeycomb Structure as Yielding Support Element for Tunnelling in Uneven Squeezing Ground 期刊论文 OAI收割 ROCK MECHANICS AND ROCK ENGINEERING, 2024, 页码: 20 作者: Liang, Weiming; Yang, Diansen; Tian, Hongming; Bian, Hanbing \| 收藏 \| 浏览/下载：2/0 \| 提交时间：2025/06/27 Tunnelling engineering Honeycomb structure Yielding support Uneven squeezing ground Numerical simulation
	Effects of the compressible layer on the long-term stability of secondary lining in a squeezing tunnel 期刊论文 OAI收割 TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY, 2024, 卷号: 149, 页码: 14 作者: Tian, Hongming; Zhang, Zheyuan; Chen, Weizhong; Tan, Xianjun; Dong, Wang \| 收藏 \| 浏览/下载：3/0 \| 提交时间：2025/06/27 Yielding support Compressible layer Squeezing ground Long-term stability of tunnel
	Failure behavior and strength model of blocky rock mass with and without rockbolts 期刊论文 OAI收割 INTERNATIONAL JOURNAL OF MINING SCIENCE AND TECHNOLOGY, 2024, 卷号: 34, 期号: 6, 页码: 747-762 作者: \| 收藏 \| 浏览/下载：2/0 \| 提交时间：2025/06/27 Blocky rock mass Rockbolt ground support Uniaxial compression test Failure mechanism Uniaxial compressive strength model
	Design and analysis for the multi-point flexible support structure of large and precision lens 期刊论文 OAI收割 Optik, 2019, 卷号: 193, 页码: 8 作者: L.M.Zhang; W.P.Wang; J.L.Wang; P.Guo; L.Hao \| 收藏 \| 浏览/下载：40/0 \| 提交时间：2020/08/24 Ground-based telescope system,Large aperture lens,Rigidity of the,support structure,Wave-front aberration,Optics
	Improvement of the U-shaped steel sets for supporting the roadways in loose thick coal seam 期刊论文 OAI收割 INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES, 2013, 卷号: 60, 页码: 19-25 作者: Song, Liang; Wang, Xin-Zhi; Jiao, Yu-Yong; Adoko, Amoussou Coffi \| 收藏 \| 浏览/下载：19/0 \| 提交时间：2018/06/05 Ground support Coal roadway Loose thick coal seam Chemical grouting material U-shaped steel sets
	Analysis of laser jamming to satellite-based detector (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China 作者: Guo L.-H.; Guo R.-H.; Wang S.-W. 收藏 \| 浏览/下载：35/0 \| 提交时间：2013/03/25 The reconnaissance satellite communication satellite and navigation satellite used in the military applications have played more and more important role in the advanced technique wars and already become the significant support and aid system for military actions. With the development of all kinds of satellites anti-satellite laser weapons emerge as the times require. The experiments and analyses of laser disturbing CCD (charge coupled detector) in near ground have been studied by many research groups but their results are not suitable to the case that using laser disturbs the satellite-based detector. Because the distance between the satellite-based detector and the ground is very large it is difficult to damage it directly. However the optical receive system of satellite detector has large optical gain so laser disturbing satellite detector is possible. In order to determine its feasibility the theoretical analyses and experimental study are carried out in the paper. Firstly the influence factors of laser disturbing satellite detector are analyzed in detail which including laser power density on the surface of the detector after long distance transmission and laser power density threshold for disturbing etc. These factors are not only induced by the satellite orbit but dependence on the following parameters: laser average power in the ground laser beam quality tracing and aiming precision and atmospheric transmission. A calculation model is developed by considering all factors which then the power density entering into the detector can be calculated. Secondly the laser disturbing experiment is performed by using LD (laser diode) with the wavelength 808 nm disturbing CCD 5 kilometer away which the disturbing threshold value is obtained as 3.5510-4mW/cm2 that coincides with other researcher's results. Finally using the theoretical model the energy density of laser on the photosensitive surface of MSTI-3 satellite detector is estimated as about 100mW/cm2 which is largely exceed the disturbing threshold and therefore verify the feasibility of using this kind of laser disturbing the satellite-based detector. According to the results. using the similar laser power density absolutely saturate the requirements to laser disturbing satellite-based detector. If considering the peak power of pulsed laser even decrease laser average power it is also possible to damage the detector. This result will provide the reliable evidences to evaluate the effect of laser disturbing satellite-based detector. 2009 SPIE.
	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：39/0 \| 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.
	CMOS APS imaging system application in star tracker (EI CONFERENCE) 会议论文 OAI收割 Advanced Materials and Devices for Sensing and Imaging II, November 8, 2004 - November 10, 2004, Beijing, China 作者: 收藏 \| 浏览/下载：59/0 \| 提交时间：2013/03/25 Small satellites are capable of performing space explore missions that require accurate attitude determination and control. However low weight size power and cost requirements limit the types of attitude sensor of small craft such as CCD are not practical for small satellites. CMOS APS is a good substitute for attitude sensors of small craft. Some of the technical advantages of CMOS APS are no blooming single power low power consumption small size and little support circuitry direct digital output simple to system design in particular radiation-hard characteristic compare with CCD. This paper discusses the application probability of CMOS APS in star tracker for small satellites further more a prototype ground-based star camera based on STAR250 CMOS image sensor has been built. In order to extract stars positions coordinates subpixel accuracy centroiding algorithm has been developed and tested on some ground-based images. Moreover the camera system star sensitivity and noise model are analyzed and the system accuracy is been evaluated. Experimental results indicate that a star camera based on CMOS APS is a viable practical attitude sensor appropriate for space small satellites.