中国科学院机构知识库网格系统: 检索

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	Impacts of climate variability and human activities on decrease in streamflow in the Qinhe River, China SCI/SSCI论文 OAI收割 2014 Bai P.; Liu W. H.; Guo M. J. 收藏 \| 浏览/下载：25/0 \| 提交时间：2014/12/24 yellow-river mann-kendall trend test last half runoff basin water vegetation precipitation sensitivity
	Responses of natural runoff to recent climatic variations in the Yellow River basin, China SCI/SSCI论文 OAI收割 2013 作者: Zhang Z.; Tang Q. 收藏 \| 浏览/下载：21/0 \| 提交时间：2014/12/24 past 50 years reference evapotranspiration water discharge last half trends variability impacts evaporation streamflow surface
	Improving land surface temperature modeling for dry land of China 期刊论文 OAI收割 JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 2011, 卷号: 116, 期号: D20104 Chen YY (陈莹莹); Yang K (阳坤); He J (何杰); Qin J (秦军); Shi, JC (Shi Jiancheng); Du, JY (Du Jinyang); He Q (He Qing) 收藏 \| 浏览/下载：82/0 \| 提交时间：2012/05/09 DATA ASSIMILATION SYSTEM MESOSCALE ETA-MODEL TIBETAN PLATEAU ROUGHNESS HEIGHT PRACTICAL NOTES YELLOW-RIVER LAST HALF PART I PARAMETERIZATION PRECIPITATION
	The design of acquisition circuit for grating digital signal based on FPGA (EI CONFERENCE) 会议论文 OAI收割 2010 3rd International Conference on Advanced Computer Theory and Engineering, ICACTE 2010, August 20, 2010 - August 22, 2010, Chengdu, China 作者: Wang W.-G. 收藏 \| 浏览/下载：43/0 \| 提交时间：2013/03/25 In order to resolve the poor suppression capability of noise and fitter interference existing in grating encoder high-rate subdivision and the poor accuracy of kam-to counting circuit the results show that the design method will help improve the controlled object of measurement precision and control accuracy. 2010 IEEE. we design a circuit based on FPGA to realize multiplier kam and filter for the output of two-way orthogonal signal generated by Incremental Optical Encoder. The system is mainly divided into three modules such as filtering multiplier kam-to and counting. The main function of filter circuit is to eliminate the jitter and noise interference existing in the quadrate encoder signals. Kam-to multiplier circuit can accurately judge the full cycle and half-cycle of incremental encoder at the same time can make fourfold multiplier. Counting circuit can use IP cores owned by Quartus II which is not restricted on the median. At last timing simulation based on Modelsim carried on the three modules
	Contrast research on interpolation and subpixel imaging in CCD geometric superresolution reconstruction (EI CONFERENCE) 会议论文 OAI收割 1st Asia Pacific Conference on Postgraduate Research in Microelectronics and Electronics, PrimeAsia 2009, November 19, 2009 - November 21, 2009, Shanghai, China 作者: Xu Y.-S.; Yang S.-W. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 In order to enhance the resolution of Charge Coupled Device (CCD) pixel with the pixel dimension and focal length of optical system unchanged the problem of CCD geometric superresolution is educed. The problem is discussed in terms of software and hardware. In software the bicubic interpolation is introduced while in hardware the subpixel imaging method is utilized. The subpixel imaging method integrates two uniform linear CCDs staggered by half dimension of pixel in one device. In operation the line frequency is doubled. At last the collected data is interweaved to synthesize a high resolution image. The two methods bicubic interpolation and subpixel imaging are simulated with Matlab7.0.1. The qualitative and quantitative analyses are given. The simulated results of lanczos and cubic spline interpolation methods are given simultaneously to show the performance of interpolation. The simulation result shows that the result images quality becomes better in both methods but compared with bicubic interpolation method the synthesized image PSNR gained from sub-pixel imaging is averagely enhanced by 2.1682dB while the elapsed time is reduced to be about one forth. The subpixel imaging method could significantly mitigate the image blur introduced by undersample. 2009 IEEE.