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	Applications of differential barometric altimeter in ground cellular communication positioning network 期刊论文 OAI收割 IET SCIENCE MEASUREMENT & TECHNOLOGY, 2020, 卷号: 14, 期号: 3, 页码: 322-331 作者: Hu, Zhengqun; Zhang, Lirong; Ji, Yuanfa \| 收藏 \| 浏览/下载：14/0 \| 提交时间：2021/12/06 cellular radio height measurement measurement errors Global Positioning System altimeters barometers least squares approximations Kalman filters surface fitting spread spectrum communication compensation matrix algebra GPS signal message structure power spectrum spread spectrum ranging signal fitting parameters least-square solution calibration compensation system noise variance matrix measurement noise variance matrix multibase station correction height information correction calculation DBA system systematic performance differential barometric altimeter ground cellular communication positioning network measurement datum distribution altitude positioning error Global Positioning System differential barometric altimetry system systematic implementation level continuous altitude measurement precise altitude measurement DBA systematic implementation aspect two dimensional curved surface fitting function sensor measurement correction filtering effect Kalman filter measuring station multiBSs navigation fusion
	Slope aspect effects of loess slides and its spatial differentiation in different geomorphologic types 期刊论文 OAI收割 ARABIAN JOURNAL OF GEOSCIENCES, 2017, 卷号: 10, 期号: 15, 页码: DOI: 10.1007/s12517-017-3135-5 作者: Qiu, Haijun; Regmi, Amar Deep; Cui, Peng; Hu, Sheng; Wang, Yanmin \| 收藏 \| 浏览/下载：24/0 \| 提交时间：2017/09/01 Loess Slide Slope Aspect Effect Geomorphological Evolution Loess Plateau
	Omni-Directional Distribution Patterns of Montane Coniferous Forest in the Helan Mountains of China 期刊论文 OAI收割 Journal of Mountain Science, 2013, 卷号: 10, 期号: 5, 页码: 724-733 PANG Yu; ZHANG Bai-ping; ZHAO Fang; YAO Yong-hui; ZHANG Shuo; QI Wen-wen 收藏 \| 浏览/下载：9/0 \| 提交时间：2013/09/23 Arid region Helan Mountains Qinghai spruce (Picea crassifolia) Aspect effect Coniferous forest Normal distribution
	Omni-directional distribution patterns of montane coniferous forest in the Helan Mountains of China SCI/SSCI论文 OAI收割 2013 Pang Y.; Zhang B. P.; Zhao F.; Yao Y. H.; Zhang S.; Qi W. W. 收藏 \| 浏览/下载：19/0 \| 提交时间：2014/12/24 Arid region Helan Mountains Qinghai spruce (Picea crassifolia) Aspect effect Coniferous forest Normal distribution slope aspect vegetation structure species richness mt. helan biodiversity
	Omni-directional distribution patterns of montane coniferous forest in the Helan Mountains of China 期刊论文 OAI收割 JOURNAL OF MOUNTAIN SCIENCE, 2013, 卷号: 10, 期号: 5, 页码: 724-733 Pang Yu(庞宇); Zhang Bai-ping; Zhao Fang; Yao Yong-hui; Zhang Shuo; Qi Wen-wen 收藏 \| 浏览/下载：13/0 \| 提交时间：2014/07/18 Arid region Helan Mountains Qinghai spruce (Picea crassifolia) Aspect effect Coniferous forest Normal distribution
	Evaluation of the operating range for ground-based infrared imaging tracking system (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China 作者: Zhang Z.-D. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 Ground-based infrared imaging tracking system (GIITS) is of great importance for aerial target warning and guard. The operating range is one of the key performance specifications on the other which should be calculated calculate the radiation power received on the detector in order to analysis whether the output signal meets the detection requirements or not analyzed and studied during the whole GIITS design process. The operating range is mostly influenced by a few factors without considering the effect of the background radiation. By improving of the traditional method including atmospheric attenuation a new operating range calculation model of the GIITS was established based on two requirements. One is that the image size of observed target should meet the requirement of the processor signal extraction. The number of the pixel occupied by target image should be more than 9. The other is that the signal noise ratio (SNR) of the GIITS should not be less than 5 to meet the requirements of the target detection probability and spatial frequency. The SNR calculation equation in form of energy is deduced and the radiation characteristic of the observed target and background are analyzed. When evaluate the operating range of the GIITS using the new method the performance of GIITS and feature of target and background. This paper firstly makes analysis and summarization on the definite localizations of the traditional operating range equation of the GIITS. The localizations are mainly in two aspects. On one hand we should successively calculate two operating range values according to two requirements mentioned above and choose the minimum value as the analytic result. In the end the dispersion of the image and the effect of image dispersion are not considered in the traditional method an evaluation of operating range for fighter aircraft is accomplished as an example. The influence factors in every aspect on operating range were explored by the calculated result. The new operating range calculation model provides the theoretical basis for the design and applications as well as the comprehensive evaluation of a GIITS. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
	Study on annular polishing for a rectangle optical flat with high aspect ratio (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, April 26, 2010 - April 29, 2010, Dalian, China 作者: Li J.; Li J.; Li J. 收藏 \| 浏览/下载：13/0 \| 提交时间：2013/03/25 The annular polishing is used to manufacture a rectangle optical flat with high aspect ratio in this paper. To control the polishing conveniently a theoretical model based on the Preston hypothesis is given. According to the model the problems related to control the power and the edge effect occurred during the process are analyzed and practically solved. Finally the surface PV of 60 nm was achieved. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Prevalence Of Shear Banding In Compression Of Zr41Ti14Cu12.5Ni10Be22.5 Pillars As Small As 150 Nm In Diameter 期刊论文 OAI收割 Acta Materialia, 2009, 页码: 3562-3571 作者: Wu XL(武晓雷); Guo YZ; Wei Q; Wang WH; Wu XL 收藏 \| 浏览/下载：751/109 \| 提交时间：2009/08/03 Bulk Metallic Glasses In Situ Transmission Electron Microscopy Shear Banding Size Effect Bulk-Metallic-Glass Strain-Rate Sensitivity Mechanical-Properties Amorphous-Alloys Dynamic Compression Aspect Ratio Deformation Behavior Fracture Temperature