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	油气管道建设工程对西北荒漠草原区生态环境影响的定量研究学位论文 OAI收割博士, 北京: 中国科学院研究生院, 2015 作者: 肖峻收藏 \| 浏览/下载：43/0 \| 提交时间：2016/08/09 廊道式工程，综合植被指数，缓冲区分析，影响范围，恢复期， linear project constructions, vegetation index, buffer analysis, effect scope, recovery period
	Remote sensing monitoring of grassland vegetation growth in the Beijing-Tianjin sandstorm source project area from 2000 to 2010 SCI/SSCI论文 OAI收割 2015 作者: Yang X. C.; Xu, B.; Jin, Y. X.; Qin, Z. H.; Ma, H. L. 收藏 \| 浏览/下载：34/0 \| 提交时间：2015/12/09 Grassland vegetation growth Remote sensing Beijing-Tianjin sandstorm source control project Project effect Agro-ecosystems china index ndvi
	退耕还林(草)工程对安塞县商品型生态农业系统的影响效应分析期刊论文 OAI收割干旱地区农业研究, 2013, 卷号: 31, 期号: 01, 页码: 206-06 崔绍芳; 王继军收藏 \| 浏览/下载：32/0 \| 提交时间：2014/10/24 退耕还林(草)工程 Grain for Green Project 商品型生态农业 ecological agriculture with commodity 影响效应 influential effect 安塞县 Ansai County
	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.
	黄土丘陵沟壑区多尺度土地利用变化特征及其演变驱动力研究学位论文 OAI收割博士, 北京: 中国科学院研究生院, 2004 张秋菊收藏 \| 浏览/下载：101/0 \| 提交时间：2011/08/24 土地利用变化驱动要素典范对应分析典范相关分析多元逐步回归分析参与式乡村评价尺度效应生态环境建设退耕还林还草黄土丘陵沟壑区。 Land Use Change Driving factors Canonical Correlation Analysis Canonical Correspond Analysis Multivariate Stepwise Regression Analysis Participatory Rural Appraisal Scale Effect Eco-environment Construction “Grain for Green” Project Hilly Area of Loess Plateau of China.