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	Design and Strength Analysis of the Lifting Process for CFETR TF Coil Manufacturing 期刊论文 OAI收割 IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, 2024, 卷号: 34 作者: Tong, Yunhua; Gao, Xiang; Cao, Lei; Du, Shijun; Wu, Yu \| 收藏 \| 浏览/下载：6/0 \| 提交时间：2024/11/22 China Fusion Engineering Test Reactor (CFETR) toroidal field (TF) coil design lifting process strength analysis
	Storage and compression design of high speed CCD (EI CONFERENCE) 会议论文 OAI收割 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 19, 2008 - November 21, 2008, Chengdu, China Cai X.; Zhai L. P. 收藏 \| 浏览/下载：57/0 \| 提交时间：2013/03/25 In current field of CCD measurement large area and high resolution CCD is used to obtain big measurement image so that speed and capacity of CCD requires high performance of later storage and process system. The paper discusses how to use SCSI hard disk to construct storage system and use DSPs and FPGA to realize image compression. As for storage subsystem Because CCD is divided into multiplex output SCSI array is used in RAID0 way. The storage system is composed of high speed buffer DMA controller control MCU SCSI protocol controller and SCSI hard disk. As for compression subsystem according to requirement of communication and monitor system the output is fixed resolution image and analog PAL signal. The compression means is JPEG2000 standard in which 9/7 wavelets in lifting format is used. 2 DSPs and FPGA are used to compose parallel compression system. The system is composed of FPGA pre-processing module DSP compression module video decoder module data buffer module and communication module. Firstly discrete wavelet transform and quantization is realized in FPGA. Secondly entropy coding and stream adaption is realized in DSPs. Last analog PAL signal is output by Video decoder. Data buffer is realized in synchronous dual-port RAM and state of subsystem is transfer to controller. Through subjective and objective evaluation the storage and compression system satisfies the requirement of system. 2009 SPIE.
	Lossless wavelet compression on medical image (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：41/0 \| 提交时间：2013/03/25 An increasing number of medical imagery is created directly in digital form. Such as Clinical image Archiving and Communication Systems (PACS). as well as telemedicine networks require the storage and transmission of this huge amount of medical image data. Efficient compression of these data is crucial. Several lossless and lossy techniques for the compression of the data have been proposed. Lossless techniques allow exact reconstruction of the original imagery while lossy techniques aim to achieve high compression ratios by allowing some acceptable degradation in the image. Lossless compression does not degrade the image thus facilitating accurate diagnosis of course at the expense of higher bit rates i.e. lower compression ratios. Various methods both for lossy (irreversible) and lossless (reversible) image compression are proposed in the literature. The recent advances in the lossy compression techniques include different methods such as vector quantization wavelet coding neural networks and fractal coding. Although these methods can achieve high compression ratios (of the order 50:1 or even more) they do not allow reconstructing exactly the original version of the input data. Lossless compression techniques permit the perfect reconstruction of the original image but the achievable compression ratios are only of the order 2:1 up to 4:1. In our paper we use a kind of lifting scheme to generate truly loss-less non-linear integer-to-integer wavelet transforms. At the same time we exploit the coding algorithm producing an embedded code has the property that the bits in the bit stream are generated in order of importance so that all the low rate codes are included at the beginning of the bit stream. Typically the encoding process stops when the target bit rate is met. Similarly the decoder can interrupt the decoding process at any point in the bil stream and still reconstruct the image. Therefore a compression scheme generating an embedded code can start sending over the network the coarser version of the image first and continues with the progressive transmission of the refinement details. Experimental results show that our method can get a perfect performance in compression ratio and reconstructive image.