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	Optimal selection of groundwater-level monitoring sites in the zhangye basin, northwest china 期刊论文 iSwitch采集 Journal of hydrology, 2015, 卷号: 525, 页码: 209-215 作者: Ran, Youhua; Li, Xin; Ge, Yong; Lu, Xuegang; Lian, Yaokang 收藏 \| 浏览/下载：115/0 \| 提交时间：2019/09/04 Groundwater Temporal stability Mean of surface with non-homogeneity Heihe river basin
	Optimal selection of groundwater-level monitoring sites in the Zhangye Basin, Northwest China SCI/SSCI论文 OAI收割 2015 作者: Ran Y. H.; Li, X.; Ge, Y.; Lu, X. G.; Lian, Y. K. 收藏 \| 浏览/下载：24/0 \| 提交时间：2015/12/09 Groundwater Temporal stability Mean of surface with non-homogeneity Heihe River Basin heihe river-basin design networks reduction variance water
	A stratified optimization method for a multivariate marine environmental monitoring network in the Yangtze River estuary and its adjacent sea SCI/SSCI论文 OAI收割 2015 作者: Gao B. B.; Wang, J. F.; Fan, H. M.; Xu, K.; Hu, M. G. 收藏 \| 浏览/下载：27/0 \| 提交时间：2015/12/09 monitoring site optimization spatial simulated annealing mean of surface with nonhomogeneity marine environment principal component analysis vegetable cultivation area constrained optimization risk-assessment china variance quality fronts performance simulation
	Spatial estimation of antibiotic residues in surface soils in a typical intensive vegetable cultivation area in China SCI/SSCI论文 OAI收割 2012 Xie Y. F.; Li X. W.; Wang J. F.; Christakos G.; Hu M. G.; An L. H.; Li F. S. 收藏 \| 浏览/下载：27/0 \| 提交时间：2012/09/04 Antibiotic residue Spatial mean Stratification Mean of Surface with Non-homogeneity (MSN) Arithmetic mean Ordinary kriging (OK) veterinary antibiotics geostatistical analysis animal manure heavy-metals environment prediction plants fate tetracycline variability
	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：26/0 \| 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.
	Design and tolerance analysis of compensator for high order aspheric surface testing (EI CONFERENCE) 会议论文 OAI收割 2009 International Conference on Optical Instruments and Technology - Optoelectronic Measurement Technology and Systems, October 19, 2009 - October 22, 2009, Shanghai, China 作者: Chen X.; Liu W.; Chen X.; Chen X. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 High accuracy is required in surface testing of 90nm nodal point lithography projecting lens. By comparing various aspheric surface testing methods the structure layout of the compensator is a meniscus positive lens combined with a Plano-convex positive lens. The design results indicate that: primary and high order aberrations are balanced well we adopt Offner null compensator to test the aspheric surface in the point diffraction interferometer at last. In this paper MTF exceeds diffraction limit an Offner compensator is presented on the base of the third order aberration theory to test concave aspheric surface root-mean-square (RMS) of wave front error /167. The F-number of the system can achieve F/1.64. By the analysis of the process of aspheric surface testing with the designed system the optical construction parameters of which is determined by introducing equal-quantities spherical aberration to compensate all orders of aspheric coefficients. The field of view of the system is 0.02 a loosen distribution of the tolerance was presented based on the accuracy of measuring apparatus. 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：27/0 \| 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.