期刊文献+
共找到6篇文章
< 1 >
每页显示 20 50 100
Fast speedometer identification in dynamic scene based on phase correlation 被引量:1
1
作者 王昱棠 付梦印 杨毅 《Journal of Beijing Institute of Technology》 EI CAS 2012年第3期394-399,共6页
Speedometer identification has been researched for many years.The common approaches to that problem are usually based on image subtraction,which does not adapt to image offsets caused by camera vibration.To cope with ... Speedometer identification has been researched for many years.The common approaches to that problem are usually based on image subtraction,which does not adapt to image offsets caused by camera vibration.To cope with the rapidity,robust and accurate requirements of this kind of work in dynamic scene,a fast speedometer identification algorithm is proposed,it utilizes phase correlation method based on regional entire template translation to estimate the offset between images.In order to effectively reduce unnecessary computation and false detection rate,an improved linear Hough transform method with two optimization strategies is presented for pointer line detection.Based on VC++ 6.0 software platform with OpenCV library,the algorithm performance under experiments has shown that it celerity and precision. 展开更多
关键词 speedometer dynamic scene image sequence phase correlation improved linear Hough transform
在线阅读 下载PDF
Phase-only Correlation Measurement with Computer-controlled LCD and CCD Image Processing System
2
作者 WANG Wen-sheng (Changchun Institute of Optics and Fine Mechanics, Changchun 130022, CHN) 《Semiconductor Photonics and Technology》 CAS 2000年第2期112-117,共6页
Using computer-controlled liquid crystal display (LCD) as an image processor and a CCD camera as a detector, phase-only correlation measurement is performed with the aid of joint transform correlation method (JTC). Th... Using computer-controlled liquid crystal display (LCD) as an image processor and a CCD camera as a detector, phase-only correlation measurement is performed with the aid of joint transform correlation method (JTC). This computer -controlled LCD-CCD image processing system may be a powerful tool for defect detection, position control and pattern recognition. It enables new possibilities in analog real-time image processing. This is of great interest in microelectronic manufacturing today and in the future. 展开更多
关键词 Liquid crystal display CCD camera Image processor Joint transform correlation Phase measurement
在线阅读 下载PDF
Correlation between large-and small-scale velocity components under Fourier filters
3
作者 Le Fang 《Theoretical & Applied Mechanics Letters》 CAS 2014年第6期68-72,共5页
By introducing the Fourier filters, we analyse the correlation between large- and small-scale velocity components in homogeneous isotropic turbulence theoretically. We show that different Fourier filters act similarly... By introducing the Fourier filters, we analyse the correlation between large- and small-scale velocity components in homogeneous isotropic turbulence theoretically. We show that different Fourier filters act similarly on this multiscale correlation with a "natural" mechanism of removing the physical correlations between large- and small-scale velocity components. This conclusion calls for the further investigation on the Hilbert-Huang decomposition to investigate the mechanism of Marusic et al (2008). 展开更多
关键词 homogeneous isotropic turbulence large-eddy simulation correlation function fourier transform
在线阅读 下载PDF
Interval arithmetic operations for uncertainty analysis with correlated interval variables 被引量:15
4
作者 Chao Jiang Chun-Ming Fu +1 位作者 Bing-Yu Ni Xu Han 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第4期743-752,共10页
A new interval arithmetic method is proposed to solve interval functions with correlated intervals through which the overestimation problem existing in interval analysis could be significantly alleviated. The correlat... A new interval arithmetic method is proposed to solve interval functions with correlated intervals through which the overestimation problem existing in interval analysis could be significantly alleviated. The correlation between interval parameters is defined by the multidimensional parallelepiped model which is convenient to describe the correlative and independent interval variables in a unified framework. The original interval variables with correlation are transformed into the standard space without correlation,and then the relationship between the original variables and the standard interval variables is obtained. The expressions of four basic interval arithmetic operations, namely addition, subtraction, multiplication, and division, are given in the standard space. Finally, several numerical examples and a two-step bar are used to demonstrate the effectiveness of the proposed method. 展开更多
关键词 operations uncertainty arithmetic correlative unified transformed considering convenient subtraction illustrated
在线阅读 下载PDF
Design of a Modified Cassegrain System Used in Joint Transform Correlator
5
作者 MA Yongli WANG Wensheng 《Semiconductor Photonics and Technology》 CAS 2010年第2期68-72,共5页
In order to detect and recognize infrared target with joint transform correlator,a modified Cassegrain optical system is designed.The main advantages of the system are large field-of-view,infrared dual-band common opt... In order to detect and recognize infrared target with joint transform correlator,a modified Cassegrain optical system is designed.The main advantages of the system are large field-of-view,infrared dual-band common optical path and compact structure.In the modified Cassegrain optical system,the working wavelengths are 3.7~4.8μm and 8~12μm,the field-of-view is 4° and the aperture is 240mm.The paraboloidal primary mirror and hyperboloidal secondary mirror are all replaced by spherical surfaces.So the problems of high machining accuracy and alignment become much easier.In order to balance the aberrations,three compensating lenses are used in the system.The total length of the system is 183mm,and the ratio of the total length to focal length is 0.68.Moreover,the system has a good performance of athermalization between negative 40℃ and positive 60℃.The design results of the system show that the MTF value of each field is greater than 0.72 when the cut-off frequency is 11lp/mm.Due to the excellent image quality of the modified optical system,the ability of Joint transform correlator(JTC)applied in target tracking and identification has been improved for further. 展开更多
关键词 optical design joint transform correlator infrared dual-band aspherical surface Cassegrain optical system
在线阅读 下载PDF
Multiple Targets Recognition for Highly-Compressed Color Images in a Joint Transform Correlator
6
作者 Abdallah K. Cherri Alshahd S. Nazar 《Optics and Photonics Journal》 2022年第5期107-127,共21页
In this paper, we are proposing a compression-based multiple color target detection for practical near real-time optical pattern recognition applications. By reducing the size of the color images to its utmost compres... In this paper, we are proposing a compression-based multiple color target detection for practical near real-time optical pattern recognition applications. By reducing the size of the color images to its utmost compression, the speed and the storage of the system are greatly increased. We have used the powerful Fringe-adjusted joint transform correlation technique to successfully detect compression-based multiple targets in colored images. The colored image is decomposed into three fundamental color components images (Red, Green, Blue) and they are separately processed by three-channel correlators. The outputs of the three channels are then combined into a single correlation output. To eliminate the false alarms and zero-order terms due to multiple desired and undesired targets in a scene, we have used the reference shifted phase-encoded and the reference phase-encoded techniques. The performance of the proposed compression-based technique is assessed through many computer simulation tests for images polluted by strong additive Gaussian and Salt & Pepper noises as well as reference occluded images. The robustness of the scheme is demonstrated for severely compressed images (up to 94% ratio), strong noise densities (up to 0.5), and large reference occlusion images (up to 75%). 展开更多
关键词 Image Compression JPEG Image Format Multiple Targets Detection Fringe-Adjusted Joint Transform correlation Random-Phase Mask
在线阅读 下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部