中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
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Connection methods in landslide susceptibility assessment: Suitability evaluation based on environmental factor type 期刊论文  OAI收割
JOURNAL OF MOUNTAIN SCIENCE, 2025, 卷号: 22, 期号: 8, 页码: 2996-3016
作者:  
Jia, Yifan;  Yang, Hongjuan;  Zhang, Shaojie;  Wang, Xiuying
  |  收藏  |  浏览/下载:1/0  |  提交时间:2025/09/28
GIS-based landslide susceptibility mapping in the Longmen Mountain area (China) using three different machine learning algorithms and their comparison 期刊论文  OAI收割
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, 2023, 页码: 15
作者:  
Huang, Ziyan;  Peng, Li;  Li, Sainan;  Liu, Ying;  Zhou, Shuang
  |  收藏  |  浏览/下载:56/0  |  提交时间:2023/10/09
Applying Bayesian Belief Networks to Assess Alpine Grassland Degradation Risks: A Case Study in Northwest Sichuan, China 期刊论文  OAI收割
FRONTIERS IN PLANT SCIENCE, 2021, 卷号: 12, 页码: 16
作者:  
Zhou, Shuang;  Peng, Li
  |  收藏  |  浏览/下载:98/0  |  提交时间:2022/01/14
Urgent landslide susceptibility assessment in the 2013 Lushan earthquake-impacted area, Sichuan Province, China SCI/SSCI论文  OAI收割
2015
作者:  
Yang Z. H.;  Lan, H. X.;  Gao, X.;  Li, L. P.;  Meng, Y. S.
收藏  |  浏览/下载:68/0  |  提交时间:2015/12/09
Three-loop autopilot design and simulation (EI CONFERENCE) 会议论文  OAI收割
2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China
作者:  
Zhang Y.
收藏  |  浏览/下载:69/0  |  提交时间:2013/03/25
In order to realize missile real-time change flight trajectory  three-loop autopilot is setting up. The structure characteristics  autopilot model  and control parameters design method were researched. Firstly  this paper introduced the 11th order three-loop autopilot model. With the principle of systems reduce model order  the 5th order model was deduced. On that basis  open-loop frequency characteristic and closed-loop frequency characteristic were analyzed. The variables of velocity ratio  dynamic pressure ratio and elevator efficiency ratio were leading to correct system nonlinear. And then autopilot gains design method were induced. System flight simulations were done  and result shows that autopilot gains played a good job in the flight trajectory  autopilot satisfied the flight index. 2012 IEEE.  
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:65/0  |  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).