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A bioinspired retinal neural network for accurately extracting small-target motion information in cluttered backgrounds 期刊论文  OAI收割
IMAGE AND VISION COMPUTING, 2021, 卷号: 114, 页码: 13
作者:  Huang, Xiao
  |  收藏  |  浏览/下载：42/0  |  提交时间：2021/11/03
Photochemical Synthesis of Nonplanar Small Molecules with Ultrafast Nonradiative Decay for Highly Efficient Phototheranostics 期刊论文  OAI收割
ADVANCED MATERIALS, 2021, 页码: 10
作者:  Li, Xiaozhen;  Zhang, Di;  Lu, Guihong;  He, Tingchao;  Wan, Yingpeng
  |  收藏  |  浏览/下载：68/0  |  提交时间：2021/08/31
Robust 3D reconstruction from uncalibrated small motion clips 期刊论文  OAI收割
VISUAL COMPUTER, 2021, 页码: 17
作者:  Li, Zhaoxin;  Zuo, Wangmeng;  Wang, Zhaoqi;  Zhang, Lei
  |  收藏  |  浏览/下载：30/0  |  提交时间：2021/12/01
Dim small target detection based on high-order cumulant of motion estimation 期刊论文  OAI收割
Infrared Physics and Technology, 2019, 卷号: 99, 页码: 86-101
作者:  Fan, Xiangsuo;  Xu, Zhiyong;  Zhang, Jianlin;  Huang, Yongmei;  Peng, Zhenming
  |  收藏  |  浏览/下载：32/0  |  提交时间：2021/05/06
Aerodynamics of hovering flight in bat 会议论文  OAI收割
23rd International Congress of Theoretical and Applied Mechanics, 中国北京/Beijing, China, 2012-08-19
作者:  Wang SZ(王士召);  He GW(何国威);  Zhang X(张星)
收藏  |  浏览/下载：23/0  |  提交时间：2014/04/02
Design of motion adjusting system for space camera based on ultrasonic motor (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
作者:  Sun Z.
收藏  |  浏览/下载：85/0  |  提交时间：2013/03/25
Drift angle is a transverse intersection angle of vector of image motion of the space camera. Adjusting the angle could reduce the influence on image quality. Ultrasonic motor (USM) is a new type of actuator using ultrasonic wave stimulated by piezoelectric ceramics. They have many advantages in comparison with conventional electromagnetic motors. In this paper  some improvement was designed for control system of drift adjusting mechanism. Based on ultrasonic motor T-60 was designed the drift adjusting system  which is composed of the drift adjusting mechanical frame  the ultrasonic motor  the driver of Ultrasonic Motor  the photoelectric encoder and the drift adjusting controller. The TMS320F28335 DSP was adopted as the calculation and control processor  photoelectric encoder was used as sensor of position closed loop system and the voltage driving circuit designed as generator of ultrasonic wave. It was built the mathematic model of drive circuit of the ultrasonic motor T-60 using matlab modules. In order to verify the validity of the drift adjusting system  was introduced the source of the disturbance  and made simulation analysis. It designed the control systems of motor drive for drift adjusting system with the improved PID control. The drift angle adjusting system has such advantages as the small space  simple configuration  high position control precision  fine repeatability  self locking property and low powers. It showed that the system could accomplish the mission of drift angle adjusting excellent. 2011 SPIE.  
Design of motion compensation mechanism of satellite remote sensing camera (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Gu S.; Yan Y.; Xu K.; Jin G.
收藏  |  浏览/下载：47/0  |  提交时间：2013/03/25
With the development of aerospace remote sensing technology  the ground resolution of remote sensing camera enhances continuously. Since there is relative motion between camera and ground target when taking pictures  the target image recorded in recording media is moved and blurred. In order to enhance the imaging quality and resolution of the camera  the image motion had to be compensated. In order to abate the effect of image motion to image quality of space camera and improve the resolution of the camera  the compensation method of image motion to space camera is researched. First  the reason of producing drift angle and adjustment principle are analyzed in this paper. This paper introduce the composition and transmission principle of image motion compensation mechanism. Second  the system adopts 80C31 as controller of drift angle  and adopts stepping motor for actuators  and adopts absolute photoelectric encoder as the drift Angle measuring element. Then the control mathematical model of the image motion compensation mechanism are deduced  and it achieve the closed-loop control of the drift angle position. At the last  this paper analyses the transmission precision of the mechanism. Through the experiment  we measured the actual precision of the image motion compensation mechanism  and compared with the theoretical analysis. There are two major contributions in this paper. First  the traditional image motion compensation mechanism is big volume and quality heavy. This has not fit for the development trend of space camera miniaturization and lightweight. But if reduce the volume and quality of mechanism  it will bring adverse effects for the precision and stiffness of mechanism. For this problem  This paper designed a image motion compensation that have some advantages such as small size  light weight at the same time  high precision  stiffness and so on. This image motion compensation can be applicable to the small optics cameras with high resolution. Second  the traditional mechanism control need to corrected  fitting and iterative for the control formula of mechanism. Only in this way  we can get the optimal control mathematical model. This paper has high precision of the control formula derived. It can achieve the high precision control without fitting  It also simplify the difficulty of control mathematical model establishment. This paper designed the range of adjusting of image motion compensation mechanism between -5 +5. Based on choosing-5  -4  -3  -2  -1  0  +1  +2  +3  +4  +4 as the expectation value of the imaginary drift angle  we get ten groups of the fact data in adjusting drift angle measured. The test results show that the precision of the drift angle control system can be achieved in 1. It can meet the system requirements that the precision of the control system is less than 3'  and it can achieve the high-precision image motion compensation. 2011 SPIE.  
United steering of control moment gyros for small satellite with limited gimbal rate (EI CONFERENCE) 会议论文  OAI收割
2010 IEEE International Conference on Information and Automation, ICIA 2010, June 20, 2010 - June 23, 2010, Harbin, Heilongjiang, China
Xu K.; Jin G.; Chen C.
收藏  |  浏览/下载：18/0  |  提交时间：2013/03/25
Single Gimbal Control Moment Gyroscopes (SGCMG) can could provide large control torque and quick attitude maneuver rate to small satellites without any increase in power  volume and mass  which will help small satellites become more powerful. Singularity avoidance and failure steering are two important problems to SGCMGs and also the main focus in this field. A new united steering law for SGCMGs with capabilities of singularity avoidance and quick transition of singularity surfaces is developed in this paper. To ensuring the existence of null motion  the commanded output of controller was changed real-timely as the variation of singularity measurement of SGCMGs  which can avoid the gimbal angle rate saturation. This developed steering law could help the SGCMGs provide real-time control toques in spite of limitation of gimbal angle rate. Simulation analysis is conducted for a certain 4-SGCMG system mounted on a small satellite. Simulation results indicate that the steering law is very effective in singularity avoidance. 2010 IEEE.  
Optimization on motion estimation algorithm based on H. 264 (EI CONFERENCE) 会议论文  OAI收割
2010 3rd International Conference on Advanced Computer Theory and Engineering, ICACTE 2010, August 20, 2010 - August 22, 2010, Chengdu, China
Wen X.; Li G.
收藏  |  浏览/下载：55/0  |  提交时间：2013/03/25
Motion estimation is a very important part of video compression. As a result of using precision of motion vector in H.264 encoder  the computational cost increases rapidly  and motion estimation is the most time-consuming stage. In this paper  based on the UMHexagonS algorithm  an optimized algorithm is proposed based on the dynamic search window selection  big hexagon and small hexagon search mode respectively  which saves motion estimation time effectively with a little quality loss. Experiments with some typical video sequences show that compared to the original UMHexagonS algorithm  this new algorithm can save about 17.851 % motion estimation time and reduce the complexity of original scheme as well as enhance the real time performance of encoder and almost has no changes in the reconstructed picture quality and bitrates. 2010 IEEE.  
Parallel estimation of translation for video stabilization (EI CONFERENCE) 会议论文  OAI收割
2010 6th International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM 2010, September 23, 2010 - September 25, 2010, Chengdu, China
作者:  Wang H.;  Liu G.;  Wang H.;  Wang H.;  Wang H.
收藏  |  浏览/下载：99/0  |  提交时间：2013/03/25
Translation motion estimation is the major aspect of video motion compensation  especially in two-dimensional turntable. This paper presents a robust parallel estimation algorithm of translation in video stabilization system. The equivalent model of translation that derived is accorded with small rotation angle comparatively. A parallel algorithm based on grey mapping is used in local motion estimation to shorten the estimation time and improve the computation efficiency. After local motion vectors are calculated  a fast filter can detect the spurious vectors avoiding possible jerks. The suggested translation estimation algorithm has been implemented on NVIDIA GTX 260  the experimental results show that  the average time of the estimation and compensation finished in 16 ms/frame  and stabilize 1k1k pixels sequence gray video up to 60 frames/s. 2010 IEEE.