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浏览/检索结果: 共6条，第1-6条 帮助 限定条件 发表日期：2005     已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 Low frequency noise study on short wavelength hgcdte photodiodes 期刊论文 Acta physica sinica, 2005, 卷号: 54, 期号: 5, 页码: 2261-2266 作者:  Huang, YC;  Liu, DF;  Liang, JS;  Gong, HM 收藏  |  浏览/下载：31/0  |  提交时间：2019/05/10 Hgcdte  Figure of merit  Low frequency noise  Deep level   CMOS APS imaging system application in star tracker (EI CONFERENCE) 会议论文 Advanced Materials and Devices for Sensing and Imaging II, November 8, 2004 - November 10, 2004, Beijing, China Li J.; Liu J.; Li X.; Liu Y.; Hao Z. 收藏  |  浏览/下载：53/0  |  提交时间：2013/03/25 Small satellites are capable of performing space explore missions that require accurate attitude determination and control. However  low weight  size  power and cost requirements limit the types of attitude sensor of small craft  such as CCD  are not practical for small satellites. CMOS APS is a good substitute for attitude sensors of small craft. Some of the technical advantages of CMOS APS are no blooming  single power  low power consumption  small size and little support circuitry  direct digital output  simple to system design  in particular  radiation-hard characteristic compare with CCD. This paper discusses the application probability of CMOS APS in star tracker for small satellites  further more  a prototype ground-based star camera based on STAR250 CMOS image sensor has been built. In order to extract stars positions coordinates  subpixel accuracy centroiding algorithm has been developed and tested on some ground-based images. Moreover  the camera system star sensitivity and noise model are analyzed  and the system accuracy is been evaluated. Experimental results indicate that a star camera based on CMOS APS is a viable practical attitude sensor appropriate for space small satellites.   The improving speed post-processing technique for blocking artifact in transform coded images (EI CONFERENCE) 会议论文 Seventh IASTED International Conference on Signal and Image Processing, SIP 2005, August 15, 2005 - August 17, 2005, Honolulu, HI, United states He B.; Cong Y.; Wang H. 收藏  |  浏览/下载：14/0  |  提交时间：2013/03/25 Based on the technique [1] and the gradient continuity of natural image  an improving speed post-processing technique for the blocking artifact in transform coded image at low bit rate is presented. Moreover  the detecting function is applied to extract the adjacent two blocks with the blocking artifact and is combined with the DCT-based adaptive post-processing technique [1] for reducing the blocking artifacts of the decoded image. The new technique is used to process JPEG compressed image and results show improvement in both effective DCT operation and peak-signal to noise ratio (PSNR) with preserving the image quality.   Noise characteristic of laser diode pumped orange-yellow solid-state laser by intracavity sum-frequency of KTP Phase matching II (EI CONFERENCE) 会议论文 ICO20: Lasers and Laser Technologies, August 21, 2005 - August 26, 2005, Changchun, China Tan H.; Gao L. 收藏  |  浏览/下载：13/0  |  提交时间：2013/03/25 The laser diode pumped Nd: YVO4 orange-yellow laser has been presented in this paper. The fundamental wavelengths of 1064nm and 1342nm oscillate simultaneous to generate the 593.5nm wavelength by intracavity sumfrequency of KTP nonlinear crystal phase matching II. The noise characteristic of laser output has been measured and analyzed in different pumping power. The relations between the amplitude noise of sum-frequency output and the longitudinal mode of fundamental frequency have been researched. The results show that the sum-frequency output is low noise if the one of fundamental wavelengths is single longitudinal mode. The experiments show that amplitude noise of intracavity sum-frequency laser is lower than that of intracavity doubled frequency laser with the same structure.   Growth of high quality and large-sized Rb0.3MoO3 single crystals by molten salt electrolysis method 期刊论文 Journal of Solid State Chemistry, 2005, 卷号: 178, 期号: 5, 页码: 1440-1444 J. F. Wang; R. Xiong; F. Yi; D. Yin; M. Z. Ke; C. Z. Li; Z. Y. Liu; J. Shi 收藏  |  浏览/下载：18/0  |  提交时间：2012/04/14 blue bronze Rb0.3MoO3  single crystal growth  electrolytic reduction  charge density wave  low-dimensional properties  wave oxide rb0.30moo3  nonlinear transport  film growth  blue bronze  k0.30moo3  k0.3moo3  noise   A new structure of low-noise CMOS differential amplifier 其他 2005-01-01 Wei, Lan; Gao, Jun; Chen, Zhongjian; Ji, Lijiu 收藏  |  浏览/下载：3/0  |  提交时间：2015/11/13 CMOS  differential amplifier  low noise  l/f noise