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	Development of NPP digital I&C system closed-loop online test system based Chock for on signal transmission array 期刊论文 OAI收割 PROGRESS IN NUCLEAR ENERGY, 2018, 卷号: 108, 期号: 无, 页码: 270-280 作者: Yang, Minghan; Wang, Jianye; Chen, Shuai; Chen, Size; Zhang, Junjun \| 收藏 \| 浏览/下载：29/0 \| 提交时间：2019/12/10 Nuclear power plant Digital I&C system Closed-loop online test system Full-scope simulator Signal transmission array
	Grid-controlled emission source for space X-ray communication 期刊论文 OAI收割 acta physica sinica, 2014, 卷号: 63, 期号: 16 作者: Ma Xiao-Fei; Zhao Bao-Sheng; Sheng Li-Zhi; Liu Yong-An; Liu Duo 收藏 \| 浏览/下载：62/0 \| 提交时间：2015/07/10 grid control X-ray source focal spot size modulation potential digital signal transmission
	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：30/0 \| 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 high-speed acquisition and processing system of the laser speckle signal on the magnetic fluid (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China 作者: Sun Y.; Sun Y.; Wan Q.-H. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 In order to achieve the dynamical detection and real-time analysis of the movement status of the magnetic fluid according to the difficulties of the detection of the magnetic fluid established a high-speed acquisition and processing system of laser speckle signal on the magnetic fluid. First of all the FPGA (EP2C8T144C8N) drived the linear array CCD(TCD1501D) to scan in the corresponding time sequence given by the computer collected the laser speckle interferometric image in rapid change on the surface of the magnetic fluid which followed the movement of the magnetic fluid and the signal collected by CCD was converted into the digital data through the high-speed A/D convertor and stored into the internal buffer FIFO of the FPGA whose width and depth were designed by the user as required. Then the FPGA sent the digital signal of the laser speckle interferometric images into the computer through the USB2.0 highspeed differential bus whose transmission rate can reach 480Mb/s in theory. Finally the distribution of the laser speckle on the magnetic fluid was messy and random which carried certain information about the surface of the magnetic fluid based on the theories of the statistic correlation and the subdivision of images analysing and processing the laser speckle interferometric images indirectly got the movement status of the magnetic fluid under the electromagnetic field. The experimental results show that: the High Speed Acquisition and Processing System has the advantage of full-court non-contact non-invasive high-precision and high reliability and so on. The detection resolution of high speed acquisition and processing system is superior to 1m and the sample rate is 3Msps which basically meets the requirements of the magnetic fluid movement state detection. 2009 SPIE.
	The compression and storage method of the same kind of medical images-DPCM (EI CONFERENCE) 会议论文 OAI收割 4th International Conference on Photonics and Imaging in Biology and Medicine, September 3, 2005 - September 6, 2005, Tianjin, China 作者: Liu H.; Liu H.; Liu H. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 Medical imaging has started to take advantage of digital technology opening the way for advanced medical imaging and teleradiology. Medical images however require large amounts of memory. At over 1 million bytes per image a typical hospital needs a staggering amount of memory storage (over one trillion bytes per year) and transmitting an image over a network (even the promised superhighway) could take minutes - too slow for interactive teleradiology. This calls for image compression to reduce significantly the amount of data needed to represent an image. Several compression techniques with different compression ratio have been developed. However the lossless techniques which allow for perfect reconstruction of the original images yield modest compression ratio while the techniques that yield higher compression ratio are lossy that is the original image is reconstructed only approximately Medical imaging poses the great challenge of having compression algorithms that are lossless (for diagnostic and legal reasons) and yet have high compression ratio for reduced storage and transmission time. To meet this challenge we are developing and studying some compression schemes which are either strictly lossless or diagnostically lossless taking advantage of the peculiarities of medical images and of the medical practice. In order to increase the Signal to-Noise Ratio (SNR) by exploitation of correlations within the source signal a method of combining differential pulse code modulation (DPCM) is presented.