中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
机构
采集方式
内容类型
发表日期
学科主题
筛选

浏览/检索结果: 共11条,第1-10条 帮助

条数/页: 排序方式:
Anion photoelectron spectroscopy and chemical bonding of ThO2- and ThO3- 期刊论文  OAI收割
JOURNAL OF CHEMICAL PHYSICS, 2018, 卷号: 148, 期号: 24, 页码: -
作者:  
Li, YL;  Zou, JH;  Xiong, XG;  Xie, H;  Tang, ZC
  |  收藏  |  浏览/下载:39/0  |  提交时间:2019/12/17
High-precision measurements of lower atmospheric temperature based on pure rotational Raman lidar 期刊论文  OAI收割
CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION, 2015, 卷号: 58, 期号: 7, 页码: 2294-2305
作者:  
Li Ya-Juan;  Song Sha-Lei;  Li Fa-Quan;  Cheng Xue-Wu;  Chen Zhen-Wei
收藏  |  浏览/下载:32/0  |  提交时间:2015/09/29
S-band J-type waveguide feeding accelerating structure for free electron laser 期刊论文  OAI收割
HIGH POWER LASER AND PARTICLE BEAMS, 2015, 卷号: 27, 期号: 4, 页码: 45109
作者:  
Hou M(侯汨);  Song NB(宋迺斌);  He X(贺祥);  Zhao FL(赵风利);  Pei SL(裴士伦)
收藏  |  浏览/下载:35/0  |  提交时间:2016/04/18
Trajectory tracking control of a quad-rotor UAV based on command filtered backstepping (EI CONFERENCE) 会议论文  OAI收割
2012 3rd International Conference on Intelligent Control and Information Processing, ICICIP 2012, July 15, 2012 - July 17, 2012, Dalian, China
Gong X.; Bai Y.; Peng C.; Zhao C.; Tian Y.
收藏  |  浏览/下载:37/0  |  提交时间:2013/03/25
A quad-rotor unmanned aerial vehicle is an under-actuated  strong coupled nonlinear system with parameters uncertainty and unknown external aerodynamic disturbance. The trajectory tracking control system with a nested double-loops structure is designed in this paper according to the coupling characteristic between the attitude angles and translational position. A PD control algorithm is proposed in the translational outer-loop to export the desired attitude signals to the attitude inner-loop. An adaptive backstepping control algorithm is designed in the inner-loop with respect to the uncertain rotational inertia and un-modeled disturbance  while in order to reduce the computational complexity the command filtered approach is introduced into the designing procedure. And finally  the numerical simulation results are presented for the trajectory tracking stabilization of a Quad-rotor  which demonstrates the excellent performance of the proposed control system and illustrate its robustness in face of disturbance and uncertain parameters. 2012 IEEE.  
Integration of rotational algorithms into dissipative particle dynamics: modeling polyaromatic hydrocarbons on the meso-scale 期刊论文  OAI收割
MOLECULAR PHYSICS, 2011, 卷号: 109, 期号: 15, 页码: 1873-1888
作者:  
Zhang, Sheng-Fei;  Xu, Jun-Bo;  Wen, Hao;  Bhattacharjee, Subir
收藏  |  浏览/下载:28/0  |  提交时间:2013/10/30
Application of precision harmonic gear drive in focusing mechanism of space camera (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Smart Structures and Materials in Manufacturing and Testing, April 26, 2010 - April 29, 2010, Dalian, China
作者:  
Zhang X.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载:33/0  |  提交时间:2013/03/25
A kind of precision harmonic gear drive in the focusing mechanism of space camera is studied  which adopt external meshing complex wave transmission mode. Wave generator is combined with an elliptic cam and a flexible bearing around it. Flexspline is a structure of single wave with the same teeth. The output shaft is supported by a single cross-roller bearing. Ball screws connected the output shaft translate the rotational motion to the linear motion  and drive the focusing mirror repeated moving along the linear guide. The output rigid wheel is connected with absolute encoder to detect displacement of focusing movement. It has the characteristics of big transmission ratio  high precision  compact structure  high efficiency and smooth running etc. According to the practical application of this harmonic gear drive in the space camera  the location relationship between the displacement of focusing structure and the focal plane movement is derived  and the system error is analyzed  its accuracy is tested with the open-loop control method. Experimental results show that transmission ratio of the instrument is 1:70  repeated positional accuracy is 2m  which meet the requirements for use. 2010 SPIE.  
Leading-order relativistic corrections to the hydrogen molecular ion 期刊论文  OAI收割
PHYSICAL REVIEW A, 2009, 卷号: 79, 期号: 6
作者:  
Zhong, Zhen-Xiang;  Yan, Zong-Chao;  Shi, Ting-Yun
收藏  |  浏览/下载:28/0  |  提交时间:2015/06/26
Triaxial shape, signature splitting, and shape coexistence in Nd-127,Nd-129,Nd-131 期刊论文  OAI收割
COMMUNICATIONS IN THEORETICAL PHYSICS, 2008, 卷号: 50, 页码: 187-192
作者:  
Dong Bao-Guo;  Ma Hai-Liang;  Yan Yu-Liang
  |  收藏  |  浏览/下载:16/0  |  提交时间:2018/07/16
Design of dual-FOV refractive/diffractive LWIR optical system (EI CONFERENCE) 会议论文  OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China
作者:  
Wang L.-J.;  Zhang J.-P.;  Wang L.-J.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载:44/0  |  提交时间:2013/03/25
An infrared-optical zoom system using binary element is proposed in this paper. The two main advantages of the zoom system introducing here are: bigger F-number and lower cost. The primary optical properties are: F/#=1  Second  Others  zoom ratio =1:4  binary element is used to correct the chromatical aberration by taking the advantage of negative dispersion characteristics and the cost of the system is lower than that of conventional ones with Zinc Selenide (Znse) material at the same level. In the binary element is rotational symmetric with one step which is easy to fabricate  in order to balance 5th spherical aberration  and dual field are 26.6 and 5.6respectively. Wider field of view is used for search and the smaller one is used for imaging details. This system uses un-cooled infrared detector with 320240 pixels and 45m pixel size. The F-number matches the sensitivity range of the detector array. Three aspects are considered during design process to make the system more satisfactory and more achievable. First  5th coma aberration and 5th astigmatic aberration  the manner of zoom is accomplished by exchanging tow lenses into the smaller field of view system layout. The lens exchange manner faces the requirement of simple system structure and good image quality in both focal points. It can also make the system more feasible in the alignment process than mechanical-zooming manner and optical-zooming manner  high-order asphere surfaces with 2th order to 10 th order are also hired in the system. Asphere surface is useful in compressing the system and improving optical system transmittance. This kind asphere surface is on industrial level featuring low cost and easy to fabricate. It is shown that good image quality can achieved by implementing five Germanium lenses and the transmittance of system is 72%. All aberrations are diffraction-limited  both spherical aberration and astigmatic aberration are corrected. When the field of view(FOV) is 26.6 and the focal length is 152mm  MTF at Nyquist frequency(11lp/mm) is great than 0.7. The spherical aberration is -0.0073. The coma aberration is 0.0978 and the astigmatic aberration is -0.013. When the field of view(FOV) is 5.6 and the focal length is 38mm  MTF at Nyquist frequency is great than 0.8 with spherical aberration -0.0046  the coma aberration 0.055 and astigmatic aberration 0.034.