中国科学院机构知识库网格系统: 检索

Terrestrial heat flow and its geodynamic implications in the northern Songliao Basin, Northeast China 期刊论文 OAI收割
GEOPHYSICAL JOURNAL INTERNATIONAL, 2022, 卷号: 229, 期号: 2, 页码: 962-983
作者: Shi, Yizuo; Jiang, Guangzheng; Shi, Shangming; Wang, Zecheng; Wang, Shejiao

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Heat flow Heat generation and transport Sedimentary basin processes Composition and structure of the continental crust Dynamics of lithosphere and mantle Asia

Controls on the present-day dynamic topography predicted from mantle flow models since 410 Ma 期刊论文 OAI收割
GEOPHYSICAL JOURNAL INTERNATIONAL, 2021, 卷号: 225, 期号: 3, 页码: 1637-1652
作者: Yang, An; Yang, Ting

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收藏 | 浏览/下载：42/0 | 提交时间：2021/09/18

Phase transitions Heat flow Structure of the Earth Numerical modelling Dynamics: convection currents and mantle plumes Dynamics of lithosphere and mantle

Alternating stress dynamics analysis of harmonic gear flexible wheel (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Electrical Insulating Materials and Electrical Engineering, EIMEE 2012, May 25, 2012 - May 27, 2012, Shenyang, Liaoning, China
作者: Li M.

收藏 | 浏览/下载：38/0 | 提交时间：2013/03/25

This article is the study of alternating stress of flexible wheel in harmonic gear drive system. Firstly then Finally according to elasticity theory to theoretically analyze flexible wheel stress based on the basic principle of sub-structure modal synthesis method based on the dynamics simulation use the software of UG to analyze the alternating stress simulation results of flexible wheel and compare theoretical results and simulation results to come conclusion. The results show that: altering stress simulation results of flexible wheel are coincident with theoretical simulation results PATRAN and ADAMS to carry out co-simulation have a deeper understand the stress change trend in the drive process of flexible wheel lay a foundation for further carrying out dynamics simulation of harmonic gear drive system. (2012) Trans Tech Publications Switzerland.

Modeling and variable structure control of a vehicle flexible manipulator (EI CONFERENCE) 会议论文 OAI收割
10th World Congress on Intelligent Control and Automation, WCICA 2012, July 6, 2012 - July 8, 2012, Beijing, China
作者: Wang Z.; Li Y.; Li Y.; Li Y.; Li Y.

收藏 | 浏览/下载：23/0 | 提交时间：2013/03/25

In this paper the mathematical modeling and the application of a new trajectory tracking control technique for hydraulic-driven rigid-flexible manipulator are concerned. To get a closer dynamic behavior of the real system both the flexible manipulator linkage and the actuator dynamics are considered. The exact dynamic model of flexible manipulator is derived using Lagrange principle and assumed modes method. The partial decoupled dynamic equation is derived using nonlinear decoupling feedback control method. The whole dynamic model is established by a driven Jacobin matrix which represents the coupling between hydraulic servo system and mechanical system. A variable structure controller with inverse dynamics is designed for trajectory tracking. To weaken the chattering of control signal saturation function is used to instead of sign function. The experimental results investigate the effectiveness of the proposed approaches. 2012 IEEE.

Research on model reference sliding mode control in roll stabilization of aerocraft (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China
Chu H.-R.

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Aimed at aerospace roll stabilization control arithmetic based on model reference sliding mode variable structure theory and chattering reduction arithmetic are formulated. Correctness and validity of arithmetic are analyzed. With flight dynamics the roll-loop mathematic model and reference model are established. Sliding hyperplane is deduced based on model reference sliding mode variable structure theory. Combing with reaching law control law is derived and stability of roll-loop is analyzed. Chattering of aileron instructions is alleviate by using boundary layer approach. Digital flying simulation result shows that variable structure control arithmetic realized roll stabilization control the roll angle is less than 5.3 under powered flight and that of unpowered flight is less than 0.5 respectively. The command fin angle is less than 1.5. High frequency chattering of fin command nearby the minimum velocity was trailed off by chattering reduction arithmetic. The sliding mode control arithmetic show good performance when aerodynamic coefficients varies 20%. The control arithmetic is easy to be implemented for its simplicity. 2011 IEEE.

Contact-impact analys with clearance hinge in flexible multi-body system (EI CONFERENCE) 会议论文 OAI收割
2nd Annual Conference on Electrical and Control Engineering, ICECE 2011, September 16, 2011 - September 18, 2011, Yichang, China
Ge M.; Jia H.; Liu B.

收藏 | 浏览/下载：52/0 | 提交时间：2013/03/25

Hinge in mechanical systems exist small clearance and contact deformation After consideration of flexible components cause the system to the wear and tear impact force reduced at the clearance noise contact time increased vibration contact-impact areas expand and clearance also caused disturbance of the rod angular velocity of the linkage. 2011 IEEE. reliability reduce or even failure[1]. Therefore the hinge clearance and the impact of flexible components in kinetic models should be considered. In this paper a nonlinear spring-damper hinge clearance model is considered to establish mechanical system structure of dynamic equations[46] through a four-bar linkage hinge with multi-clearance rotation of ADAMS dynamic simulation for dynamics simulation study. Simulation results show that hinge clearance and link flexible in Four-link mechanism dynamics have a great impact on performance: connection with the clearance lead to pin holes to produce a series of collisions and a larger initial impact force

Development direction and task of the geodynamical research in China 期刊论文 OAI收割
ACTA PETROLOGICA SINICA, 2010, 卷号: 26, 期号: 11, 页码: 3159-3176
作者: Teng JiWen; Yang Hui; Zhang XueMei

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收藏 | 浏览/下载：17/0 | 提交时间：2018/09/26

Continental dynamics Structure of the crust and the mantle Substance and energy exchanges Deep processes and dynamic mechanism Direction and task

Development direction and task of the geodynamical research in China 期刊论文 OAI收割
ACTA PETROLOGICA SINICA, 2010, 卷号: 26, 期号: 11, 页码: 3159-3176
作者: Teng JiWen; Yang Hui; Zhang XueMei

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收藏 | 浏览/下载：21/0 | 提交时间：2018/09/26

Continental dynamics Structure of the crust and the mantle Substance and energy exchanges Deep processes and dynamic mechanism Direction and task

Gimbal displacement error analysis on an electro-optical seeker (EI CONFERENCE) 会议论文 OAI收割
Optical Design and Testing IV, October 18, 2010 - October 20, 2010, Beijing, China
作者: Zhang X.; Zhang X.; Zhang X.

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It is essential to analyze the gimbal displacement errors for a seeker due to the importance for cueing of targets and tracking for the final approach. Otherwise for a seeker electro-driven with a concentric glass dome the large errors will decrease the picking pointing and tracking precision rooted from the displacement errors existing between the rotation center of the optical system and the gimbal. And the gimbaled camera system displacement errors are never eliminated but reduced due to the geometric errors consists of geometric tolerances of gimbal structure manufacture installation and vibration coming from working environment. In this paper the gimbal displacement errors in an electro-optically stabilized platform resulting from geometric errors and environment errors were analyzed and shown in detail. The mathematical modal of the gimbal displacement errors created based on multi-body dynamics demonstrated the connection between the gimbal displacement errors and the stabilized platform. Taking a visible light image seeker as a case the diameter is 120mm and the geometric tolerances came from the values of primary design and the vibration data came from the environmental vibration test on the pitch-yaw seeker and at the same time the errors resulting from installation were considered too. Based on calculating the maximum gimbal displacement error will reach to 0.2mm for pitching angle smaller than 40 and yawing angle smaller than 60. However the critical parts have been found out according to the probability theory and the reliability analysis successfully used in the paper and finally the maximum gimbal displacement error reduced to 0.1mm which is acceptable corresponding to the picking pointing and tracking precision for an optical imaging seeker. 2010 Copyright SPIE - The International Society for Optical Engineering.

Design of optical elements for imaging the earth's plasmasphere (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging, ISPDI 2007: Optoelectronic System Design, Manufacturing, and Testings, September 9, 2007 - September 12, 2007, Beijing, China
作者: Chen B.; Chen B.; Wang X.-K.

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Studying the distribution of He+ in Earth's plasmasphere by detecting its resonantly-scattered emission at 304A will record the structure and dynamics of the cold plasma in Earth's plasmasphere on a global scale. EUV imaging systems usually utilizes near normal incidence optics including multilayer mirror and filter. In this paper the space condition of the Earth's plasmasphere to confirm the expected performance of mirror and filter for this task were analyzed and some guidelines for the design of the optical elements were introduced. In order to achieve higher response at 304A and reduce 584A radiation for the optical system a new multilayer coating of Mo/Si with UOx (x=2-3) was developed and it is indicated that promising filter material is Al/C with a nickel mesh. In addition we compute the reflectance of multilayer mirror based on optical constants and the transmission of the filter based on atomic scattering factor. The results show the multilayer mirror has high reflectance of 26.27% at 304 Aand low reflectance of 0.60% at 584A. Finally the conversion efficiency of mirror coupled with filter is 6.88% at 304A and 0.01% at 584 A.