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18条,第1-10条 帮助

条数/页: 排序方式:
Plasma edge density fluctuation measurements via lithium beam emission spectroscopy on EAST 期刊论文  OAI收割
PLASMA SCIENCE & TECHNOLOGY, 2022, 卷号: 24
作者:  
Wu, Donggui;  Hu, Guanghai;  Zoletnik, S.;  Xu, Guosheng;  Ding, Siye
  |  收藏  |  浏览/下载:91/0  |  提交时间:2022/05/16
Study on infrared transparent radar double band-pass filter (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Mechatronics and Materials Processing, ICMMP 2011, November 18, 2011 - November 20, 2011, Guangzhou, China
Jia H. Y.; Feng X. G.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
To realize the functions of infrared transparent as well as radar double- pass Band  A Y loop and Y slot compound element Frequency Selective Surface (FSS) structure is proposed  which takes an infrared transparent inductive mesh as a substrate. The proposed structure is analyzed based on Galerkin spectral method. The transitivity of infrared (3um-5um) as well as the radar double passed band with two resonance frequencies (31GHz and 54GHz) is discussed. The result reveals that this structure has function of infrared transparent as well as stable radar double-band filter with effective shielding effect on S-band and C-band radar electromagnetic waves. The design with multiple passband is suitable for radar/IR composite guidance and it also offers a kind of new thinking way of design for multi-mode compound guidance systems. 2011 Trans Tech Publications.  
The research on adaptive measurement of angular acceleration for photoelectric servo turntable (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Mechatronic Science, Electric Engineering and Computer, MEC 2011, August 19, 2011 - August 22, 2011, Jilin, China
作者:  
Guo J.;  Chen J.;  Guo J.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
The paper proposes a new measurement method of angular acceleration for photoelectric servo turntable. Piezoelectric angular acceleration sensor is used to measure angular acceleration directly  Adaptive FIR filter based on LMS algorithm is established on DSP  by which angular acceleration signal can be filtered and corrected errors adaptively  then angular acceleration signals can be measured adaptively. This method avoids measurement errors and calculation noise by computing angular acceleration indirectly  thus improving measurement precision and making measurement results better than traditional methods. The gotten angular acceleration can be sent to servo control mechanism as feed forward control signals to improve control effects of servo turntable significantly. 2011 IEEE.  
The application of MATLAB/ embedded IDE Link CC in the design of DSP system (EI CONFERENCE) 会议论文  OAI收割
2011 4th International Conference on Intelligent Computation Technology and Automation, ICICTA 2011, March 28, 2011 - March 29, 2011, Shenzhen, Guangdong, China
Le S.; Shu-Mei Z.; Xin L.
收藏  |  浏览/下载:37/0  |  提交时间:2013/03/25
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:63/0  |  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).  
Sort optimization algorithm of median filtering based on FPGA (EI CONFERENCE) 会议论文  OAI收割
2010 International Conference on Machine Vision and Human-Machine Interface, MVHI 2010, April 24, 2010 - April 25, 2010, Kaifeng, China
作者:  
Li S.
收藏  |  浏览/下载:32/0  |  提交时间:2013/03/25
The research on servo control technology of O-E theodolite based on angular acceleration sensor (EI CONFERENCE) 会议论文  OAI收割
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Wei L.; Jin G.; Juan C.
收藏  |  浏览/下载:24/0  |  提交时间:2013/03/25
A new servo control methods for O-E theodolite is presented in this paper. The methods integrates optimally feed forward and feedback control  and adopts acceleration delay compensation based on velocity delay compensation  then achieves servo control of O-E theodolite effectively. Furthermore  Angular acceleration sensor is applied as information resources  and adaptive filter is formed to provide with feed forward control signal in the methods. For double closed loop servo control system of O-E theodolite  the location correction loop and velocity correction loop are analyzed and designed. Simulation and experimental results show that comparing with traditional methods  this servo control methods can improve significantly tracking precision and stability of O-E theodolite. 2010 IEEE.  
Design and image restoration research of a cubic-phase-plate system (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, April 26, 2010 - April 29, 2010, Dalian, China
作者:  
Zhang J.;  Zhang J.;  Zhang J.;  Shi G.;  Zhang X.
收藏  |  浏览/下载:28/0  |  提交时间:2013/03/25
Wave-front coding technology is a novel jointly optical and digital imaging technology which can greatly extend the depth of focus of optical systems. The image restoration process is an important part of wave-front coding technology. Using wave-front coding makes the modulation transfer function(MTF) values of the optical systems change little over a range of several times the depth of focus  which means the system MTF is quite insensitive to defocus  and there is no zero in the passband. So we can design a single filter for the restoration of images in different defocus positions. However  it's hard to avoid noise during image acquisition and transmission processes. These noises will be amplified in the image restoration  especially in the high frequency part when the MTF drop is relatively low. The restoration process significantly reduces the system signal to noise ratio this way. Aimed at the problem of noise amplification  a new algorithm was proposed which incorporated wavelet denoising into the iterative steps of Lucy-Richardson algorithm. Better restoration results were obtained through the new algorithm  effectively solving the noise amplification problem of original LR algorithm. Two sets of identical triplet imaging systems were designed  in one of which the cubic-phase-plate was added. Imaging experiments of the manufactured systems were carried  and the images of a traditional system and a wave-front coded system before and after decoding were compared. The results show that the designed wave-front coded system can extend the depth of focus by 40 times compared with the traditional system while maintaining the light flux and the image plane resolution. 2010 Copyright SPIE - The International Society for Optical Engineering.  
A 3-axis simulator for spacecraft attitude control research (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
作者:  
Dai L.
收藏  |  浏览/下载:33/0  |  提交时间:2013/03/25
This article presents the details of a new 3-axis simulator for spacecraft attitude control research and simulation. The air bearing allows the test bed to rotate about three axes with tiny friction. The attitude determination system consists of three fibre optical gyros  an inclinometer and a magnetometer. The actuator of the system consists of three reaction flywheels and four control moment gyros (CMG). Mathematical models of the sensors and actuators are given to help algorithm design. An extended Kalman filter was designed to provide attitude information for controller. Mathematical simulation results prove the attitude determination system can achieve high precision. A coulomb friction model of reaction wheels is given with experimental results. A friction compensation algorithm was developed to raise the pointing accuracy of the control system. The article also describes the details of the hardware structure. A PD stabilizing controller is implemented to test the validation of the whole control system at last. 2010 IEEE.  
New phase measurement method for laser rangefinder (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China
作者:  
Meng Z.;  Meng Z.
收藏  |  浏览/下载:31/0  |  提交时间:2013/03/25
A new phase measurement method is designed and presented by using the technique of signal shifting phase and the technique of signal multiplication for laser rangefinder. The intensity of laser light is modulated by cosine circuit signal  at the same time the cosine circuit signal is thansformed sine signal by the shifting phase technique. Two signals mentioned above are multiplied by received signal from the target respectively  then being transmitted into signal processor after passing through low band filter respectively. The result of phase-shift between the received signal and sent signal is calculated by means of signal processor and time-counter with double frequency of modulation signal. The proposed system is composed of four units such as control and count unit  emitting and receiving unit of laser light  signal processing unit and result display unit. The two most advantages of proposed system over others are its ability of proper isolation which reduces crosstalk and its independency thermal drift. Theoretical calculations and experimental results have shown the accuracy better than 2 mm. 2010 Copyright SPIE - The International Society for Optical Engineering.