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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.  
典型区域中持久性有机污染物的分布空间规律与源解析 学位论文  OAI收割
博士, 北京: 中国科学院研究生院, 2007
傅珊
收藏  |  浏览/下载:74/0  |  提交时间:2010/05/27
Development of a new diffuse near infrared food measuring (EI CONFERENCE) 会议论文  OAI收割
Sitxh International Symposium on Instrumentation and Control Technology: Signal Analysis, Measurement Theory, Photo-Electronic Technology, and Artificial Intelligence, October 13, 2006 - October 15, 2006, Beijing, China
作者:  
Zhang J.;  Zhang J.;  Zhang J.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
Industries from agriculture to petrochemistry have found near infrared (NIR) spectroscopic analysis useful for quality control and quantitative analysis of materials and products. The general chemical  polymer chemistry  petrochemistry  agriculture  food and textile industries are currently using NIR spectroscopic methods for analysis. In this study  we developed a new sort NIR instrument for food measuring. The instrument consists of a light source  12 filters to the prismatic part. The special part is that we use a mirror to get two beams of light. And two PbS detectors were used. One detector collected the radiation of one light beam directly and the value was set as the standard instead the standard white surface. Another light beam irradiate the sample surface  and the diffuse light was collected by another detector. The value of the two detectors was compared and the absorbency was computed. We tested the performance of the NIR instrument in determining the protein and fat content of milk powder. The calibration showed the accuracy of the instrument in practice.  
Multiwavelet based multispectral image fusion for corona detection (EI CONFERENCE) 会议论文  OAI收割
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Wang X.;  Yang H.-J.;  Sui Y.-X.;  Yan F.;  Yan F.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
Image fusion refers to the integration of complementary information provided by various sensors such that the new images are more useful for human or machine perception. Multiwavelet transform has simultaneous orthogonality  symmetry  compact support  and vanishing moment  which are not possible with scalar wavelet transform. Multiwavelet analysis can offer more precise image analysis than wavelet multiresolution analysis. In this paper  a new image fusion algorithm based on discrete multiwavelet transform (DMWT) to fuse the dual-spectral images generated from the corona detection system is presented. The dual-spectrum detection system is used to detect the corona and indicate its exact location. The system combines a solar-blind UV ICCD with a visible camera  where the UV image is useful for detecting UV emission from corona and the visible image shows the position of the corona. The developed fusion algorithm is proposed considering the feature of the UV and visible images adequately. The source images are performed at the pixel level. First  a decomposition step is taken with the DMWT. After the decomposition step  a pyramid for each source image in each level can be obtained. Then  an optimized coefficient fusion rule consisting of activity level measurement  coefficient combining and consistency verification is used to acquire the fused coefficients. This process reduces the impulse noise of UV image. Finally  a new fused image is obtained by reconstructing the fused coefficients using inverse DMWT. This image fusion algorithm has been applied to process the multispectral UV/visible images. Experimental results show that the proposed method outperforms the discrete wavelet transform based approach.