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	土剪破坏次声监测试验研究期刊论文 OAI收割力学学报, 2020, 卷号: 52, 期号: 3, 页码: 877 作者: 陈乔; 张阔; 陈吉龙; 张少杰; 吕君 \| 收藏 \| 浏览/下载：15/0 \| 提交时间：2020/08/24 direct shear of soil soil landslide infrasound variable size mean square power monitoring 土体直剪土质滑坡次声变尺寸均方功率监测
	Roughness analysis of optical surfaces by X-ray scattering (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electronics and Optoelectronics, ICEOE 2011, July 29, 2011 - July 31, 2011, Dalian, China 作者: Chen B.; Chen B. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 A grazing incidence x-ray scattering (XRS) method Order perturbation theory (FOPT) is stated briefly and an experimental facility based on an improved X-ray diffraction has been introduced which can work with high performance. The x-ray scattering distributions of two super smooth silicon samples measured at the incidence angle 0.2 degree as the x-ray wavelength is 0.154 nm have been given and analyzed by the FOPT to give information about the surface profiles. As a comparison the root mean square (RMS) surface roughness grey-scale maps and one-dimensional power spectral density (1D PSD) have been derived from the atomic-force microscope (AFM) data. The results evaluated by FOPT are in good agreement with that of AFM which indicates that x-ray scattering method is a practical characterization for the investigation of super smooth surfaces. 2011 IEEE.
	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：26/0 \| 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.
	Suppression of additive noise using a power spectral density MMSE estimator 期刊论文 OAI收割 IEEE SIGNAL PROCESSING LETTERS, 2004, 卷号: 11, 期号: 6, 页码: 585-588 作者: Ding, GH; Huang, T; Xu, B 收藏 \| 浏览/下载：17/0 \| 提交时间：2015/11/06 exponential distribution. Gaussian distribution minimum mean-square error (MMSE) power spectral density (PSD)