中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
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Implementation of Viscoelastic Artificial Boundary and Seismic Motion Input Method in Three-Dimensional Discontinuous Deformation Analysis Method 期刊论文  OAI收割
ROCK MECHANICS AND ROCK ENGINEERING, 2024, 页码: 21
作者:  
Lin, Si-huang;  Deng, Tao;  Zheng, Lu;  Zhang, Hong;  Wu, Wei
  |  收藏  |  浏览/下载:2/0  |  提交时间:2025/06/27
Earthquake input mechanism for time-domain analysis of tunnels in layered ground subjected to obliquely incident P- and SV-waves 期刊论文  OAI收割
ENGINEERING STRUCTURES, 2019, 卷号: 181, 期号: -, 页码: 374-386
作者:  
Zhao, Wusheng;  Chen, Weizhong;  Yang, Diansen;  Tan, Xianjun;  Gao, Hou
  |  收藏  |  浏览/下载:24/0  |  提交时间:2020/04/08
Three-sample rotation vector algorithm with angular rate input (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:  
Zhang Y.
收藏  |  浏览/下载:24/0  |  提交时间:2013/03/25
In order to research the attitude algorithm with angular rate input under the conical motion  a optimal threesample rotation vector algorithm based on single-step Newton backward interpolation is proposed. Using the principle of limited rigid body rotation and the characteristic of angular rate input  three-sample rotation vector algorithm is derivated. To minimum attitude errors  three-sample rotation vector algorithm is optimized. Three angular rate extraction methods of singlestep entire sample recursion  multi-step entire sample and singlestep Newton backward interpolation are proposed. Under the condition of conical motion with semi-cone angle 3 and angular frequency 2rad/s  simulation is done. The simulation results show that single-step Newton backward interpolation is superior to the other two methods  and its maximum error peak is 0.01  error drift rate is 0.036/h. Experiments in three-axis flying turntable with the same parameters are carried out  and the results show that error drift rates of three-channels are less than those of traditional quaternion  which are 13.53%  12.08% and 23.68% lower respectively. It also verified that the new algorithm can perform a high accuracy under the conical motion. 2011 IEEE.  
Method of improving the accuracy of image motion measurement for panoramic aerial cameras (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices for Detector, Imager, Display, and Energy Conversion Technology, April 26, 2010 - April 29, 2010, Dalian, China
作者:  
Jia P.
收藏  |  浏览/下载:27/0  |  提交时间:2013/03/25
To improve the accuracy of image motion measurement for panoramic aerial cameras  the paper proposed a method of real-time image motion measurement based on 2D spatial correlation. An auxiliary area CCD is positioned paralleled to the main linear TDI CCD in the focal plane of the camera. For every frame of the image sequence taken by the auxiliary CCD  a prediction on the displacement of the current image in the flight direction is made based on the forward image motion velocity. The current and the reference images are combined together for 2D-correlation  which products an image motion vector. By decomposing the vector  both the forward and pendulum-swing image motions can be determined. The demanding computational requirements for the real-time 2D-correlation are covered by a joint transform optical correlator. Simulation test results show that the accuracy is improved and the measurement error is within 0.2 pixels for input images with SNR=1 dB. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Panoramic aerial camera image motion measurement using a hybrid system (EI CONFERENCE) 会议论文  OAI收割
2010 3rd IEEE International Conference on Computer Science and Information Technology, ICCSIT 2010, July 9, 2010 - July 11, 2010, Chengdu, China
作者:  
Jia P.
收藏  |  浏览/下载:28/0  |  提交时间:2013/03/25
Image motion compensation is significantly important for aerial camera photograph. To execute the compensation  we must determine the image motion exactly. This paper proposes a method of real-time image motion measurement for panoramic aerial cameras based on image processing using a hybrid system. Two cameras are simultaneously used in the hybrid system. One main linear CCD for imaging  while the other auxiliary low resolution high frame rate area CCD for determining the image motion based on 2D spatial correlation. The demanding computational requirements for the real-time 2D spatial correlation are covered by a joint transform optical correlator. Simulation test results show that the accuracy is improved and the measurement error is within 0.2 pixels for input images with SNR=1 dB. 2010 IEEE.  
Nonlinear control design for system with mechanical resonance based on two tracking-differentiators (EI CONFERENCE) 会议论文  OAI收割
2010 IEEE International Conference on Mechatronics and Automation, ICMA 2010, August 4, 2010 - August 7, 2010, Xi'an, China
作者:  
Li J.;  Li Y.;  Li Y.;  Li Y.;  Li Y.
收藏  |  浏览/下载:29/0  |  提交时间:2013/03/25
A nonlinear control strategy for controlling a motion system with mechanical resonance is presented in this paper. A mathematical model of the servo system is derived according to the parameters of an actual system. By using two Tracking-Differentiators  reference input and system output are tracked and their differential signals are given simultaneously. A nonlinear PD control law in velocity loop is designed based on non-smooth feedback. The simulation results show that the control law is superior remarkably in performance to linear PD control law and the classical PID control law. Tracking-Differentiator resolves the contradiction between rapidity and overshoot of system response. The nonlinear PD control law improves system dynamic performance and intensifies the ability of disturbance rejection. The control design achieved in this paper makes the servo system more robust. 2010 IEEE.  
Implementation and stability analysis of the fuzzy controller based on electric-driven simulation turntable (EI CONFERENCE) 会议论文  OAI收割
ISECS International Colloquium on Computing, Communication, Control, and Management, CCCM 2008, August 3, 2008 - August 4, 2008, Guangzhou, China
Xie M.-J.; Wang L.-M.; Wang Z.-Q.
收藏  |  浏览/下载:23/0  |  提交时间:2013/03/25
Fuzzy controller was used to resolve the problem of fast tracking and overshoot in electric-driven simulation turntable  for its essence belongs to PD control In this system  the control rules of fuzzy controller were established according to the step dynamic response process  for the speed loop of this system was predigested to be second-orders system. The describing function method was adopted to analyze the stability of the fuzzy control system. It gave the information of stability of system intuitively. The fuzzy controller had been applied in this system successfully. The simulation turntable had no overshooting nearly when its step input signal was close to 90. Experimental results show the implementation method of fuzzy controller is not only simple but also effectual in engineering practice. It also provides an approach of design of fuzzy controller for motion control system. 2008 IEEE.  
Head-raising motion of snake-like robots 会议论文  OAI收割
IEEE International Conference on Robotics and Biomimetics (ROBIO 2004), Shenyang, China, August 22-26, 2004
作者:  
Ye ZL(叶长龙);  Ma SG(马书根);  Li B(李斌);  Wang YC(王越超)
收藏  |  浏览/下载:29/0  |  提交时间:2012/06/06