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	Contrasting characteristics and drivers of dry and warm snow droughts in China 's largest inland river basin 期刊论文 OAI收割 JOURNAL OF HYDROLOGY-REGIONAL STUDIES, 2024, 卷号: 53, 页码: 25 作者: Wang, Zhixia; Huang, Shengzhi; Singh, Vijay P.; Mu, Zhenxia; Leng, Guoyong \| 收藏 \| 浏览/下载：27/0 \| 提交时间：2024/07/24 Dry-type and warm-type snow droughts Snow drought characteristics and dynamics Optimal parameters-based geographical detec-tor model Random forest Ocean-atmosphere couplings strength
	A low order characteristic-nonconforming finite element method for nonlinear Sobolev equation with convection-dominated term 期刊论文 OAI收割 MATHEMATICS AND COMPUTERS IN SIMULATION, 2015, 卷号: 114, 页码: 25-36 作者: Shi, Dongyang; Tang, Qili; Gong, Wei \| 收藏 \| 浏览/下载：24/0 \| 提交时间：2018/07/30 Characteristics Sobolev equation Nonconforming finite element The optimal order error estimates Global superconvergence
	Failure Characteristics and Support Optimal Design of Columnar Jointed Rock Mass at a Diversion Tunnel 会议论文 OAI收割 Jinan, PEOPLES R CHINA, MAY 24-26, 2013 作者: Zhu, Xiangdong; Hu, Lianxing; Jiang, Quan; Li, Shaojun; Li, Jun \| 收藏 \| 浏览/下载：22/0 \| 提交时间：2018/06/05 failure characteristics support optimal design columnar jointed rock mass excavation unloading
	Debris flow formation conditions and optimal characteristics of drainage canal following Wenchuan earthquake 期刊论文 OAI收割 ENVIRONMENTAL EARTH SCIENCES, 2012, 卷号: 65, 期号: 4, 页码: 1005-1012 作者: You, Yong; Liu, Jinfeng; Chen, Xingzhang; Pan, Huali 收藏 \| 浏览/下载：16/0 \| 提交时间：2013/01/07 Wenchuan earthquake Zhangjia gully Debris flow hazards Drainage canal Optimal characteristics
	The new approach for infrared target tracking based on the particle filter algorithm (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: Sun H.; Han H.-X.; Sun H. 收藏 \| 浏览/下载：60/0 \| 提交时间：2013/03/25 Target tracking on the complex background in the infrared image sequence is hot research field. It provides the important basis in some fields such as video monitoring precision and video compression human-computer interaction. As a typical algorithms in the target tracking framework based on filtering and data connection the particle filter with non-parameter estimation characteristic have ability to deal with nonlinear and non-Gaussian problems so it were widely used. There are various forms of density in the particle filter algorithm to make it valid when target occlusion occurred or recover tracking back from failure in track procedure but in order to capture the change of the state space it need a certain amount of particles to ensure samples is enough and this number will increase in accompany with dimension and increase exponentially this led to the increased amount of calculation is presented. In this paper particle filter algorithm and the Mean shift will be combined. Aiming at deficiencies of the classic mean shift Tracking algorithm easily trapped into local minima and Unable to get global optimal under the complex background. From these two perspectives that "adaptive multiple information fusion" and "with particle filter framework combining" we expand the classic Mean Shift tracking framework.Based on the previous perspective we proposed an improved Mean Shift infrared target tracking algorithm based on multiple information fusion. In the analysis of the infrared characteristics of target basis Algorithm firstly extracted target gray and edge character and Proposed to guide the above two characteristics by the moving of the target information thus we can get new sports guide grayscale characteristics and motion guide border feature. Then proposes a new adaptive fusion mechanism used these two new information adaptive to integrate into the Mean Shift tracking framework. Finally we designed a kind of automatic target model updating strategy to further improve tracking performance. Experimental results show that this algorithm can compensate shortcoming of the particle filter has too much computation and can effectively overcome the fault that mean shift is easy to fall into local extreme value instead of global maximum value.Last because of the gray and fusion target motion information this approach also inhibit interference from the background ultimately improve the stability and the real-time of the target track. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
	Structure optimization of strap-down inertial navigation system support (EI CONFERENCE) 会议论文 OAI收割 2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China 作者: Wang J.; Sun H.; Sun H. 收藏 \| 浏览/下载：31/0 \| 提交时间：2013/03/25 In order to meet the requirement of inertial navigation components and minimizing the system's weight and topological optimization was conducted. Then topological optimization and size optimization were conducted under conditions of random vibration and impact. Firstly according to the dynamic characteristics of missile and requirement of inertial navigation system the structure of inertial navigation support was designed according to types of missile connection and space arrangement of electronic components the method of transforming multi-loading cases to multi-loading constraints was used to optimizing the size of the support under conditions of random vibration and impact. Comparing to the original support structures RMS accelerations in installed points reduced by 25.2% under random vibration the weight of optimal structures reduced by 28.1% the structures also met the requirement of inertial navigation system under condition of impact. The support structure shows improvements in both dynamic characteristic and light weight comparing with the original one. 2011 IEEE.
	Theoretical analysis of emission characteristics of second-order distributed feedback semiconductor lasers (EI CONFERENCE) 会议论文 OAI收割 Semiconductor Lasers and Applications IV, October 18, 2010 - October 19, 2010, Beijing, China 作者: Liu Y.; Liu Y.; Qin L.; Liu Y.; Wang L. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 Based on the modified coupled-wave theory the emission characteristics including threshold gain photon density distribution in the cavity and external differential quantum efficiency for second-order DFB lasers are investigated. Numerical simulation results show that for given device structure with wavelength of 1.55 m the feedback coupling coefficient and the surface radiation coupling coefficient of the second-order grating have great influence on the emission characteristics of the device. By choosing different duty cycles of the grating we can change the two coupling coefficients which affect the emission characteristics. For an overall consideration an optimal duty cycle of 0.43 is chosen. The optimized results show that the device works without degeneracy modes and spatial burning hole. Besides the side-mode suppress ratio (SMSR) and external differential quantum efficiency reach as high as 42 dB and 47% respectively. 2010 SPIE.
	Double-swing method used for polishing off-axis aspherical mirrors (EI CONFERENCE) 会议论文 OAI收割 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China 作者: Chen Y.; Song S.-M.; Xuan B.; Wang P.; Li J.-F. 收藏 \| 浏览/下载：45/0 \| 提交时间：2013/03/25 Based on the characteristics of off-axis aspherical surface the comparison of simulation effects under different parameters is made. In order to achieve optimal parameters a new method used for polishing off-axis aspherical mirrors-Double-Swing Method (DSM) is proposed in this paper a high order off-axis rectangle aspherical mirror has been polished by DSM. The final result of profile measurements of 12nm and the polishing mechanism of DSM is introduced. The mathematical model of the DSM with steady movement state is established.The movement of this mathematical model is simulated in a programming language RMS is achieved. The result indicates that the method is of practice and has even higher working efficiency and precision. 2009 SPIE.