中国科学院机构知识库网格系统: 检索

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	Detection of Periodic Signals With Time-Varying Coefficients From CMONOC Stations in China by Singular Spectrum Analysis 期刊论文 OAI收割 IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, 2023, 卷号: 61, 页码: 5802812 作者: Wu, Shuguang; Li, Zhao; Li, Houpu; Bian, Shaofeng; Ouyang, Hua \| 收藏 \| 浏览/下载：4/0 \| 提交时间：2024/01/04 Crustal Movement Observation Network of China (CMONOC) stations periodic signals with time-varying coefficients (PSTC) root mean square error (RMSE) improve-ment rate singular spectrum analysis (SSA) method
	Does agroecosystem model improvement increase simulation accuracy for agricultural N2O emissions? 期刊论文 OAI收割 AGRICULTURAL AND FOREST METEOROLOGY, 2021, 卷号: 297, 页码: 12 作者: Zhang, Yajie; Yu, Qiang \| 收藏 \| 浏览/下载：23/0 \| 提交时间：2021/03/15 Nitrous oxide emission Agroecosystem model evolution Coefficient of determination Root mean square error Meta-analysis
	Evaluation of ionospheric height assumption for single station GPS-TEC derivation 期刊论文 OAI收割 ADVANCES IN SPACE RESEARCH, 2017, 卷号: 60, 期号: 2, 页码: 286-294 作者: Lu, Weijun; Ma, Guanyi; Wang, Xiaolan; Wan, Qingtao; Li, Jinghua 收藏 \| 浏览/下载：57/0 \| 提交时间：2017/09/01 Ionosphere Single layer model Total electron content Instrumental bias Root mean square error
	Research on M Dwarf Sub-Classification Based on the Measurement of Residual Distribution 期刊论文 OAI收割 SPECTROSCOPY AND SPECTRAL ANALYSIS, 2016, 卷号: 36, 期号: 7, 页码: 2279-2283 作者: Kang Chao; Pan Jing-chang; Yi Zhen-ping; Wei Peng; Jiang Bin 收藏 \| 浏览/下载：22/0 \| 提交时间：2016/10/27 Residual distribution Distance measurement Root-mean-square error
	Design and tolerance analysis of compensator for high order aspheric surface testing (EI CONFERENCE) 会议论文 OAI收割 2009 International Conference on Optical Instruments and Technology - Optoelectronic Measurement Technology and Systems, October 19, 2009 - October 22, 2009, Shanghai, China 作者: Chen X.; Liu W.; Chen X.; Chen X. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 High accuracy is required in surface testing of 90nm nodal point lithography projecting lens. By comparing various aspheric surface testing methods the structure layout of the compensator is a meniscus positive lens combined with a Plano-convex positive lens. The design results indicate that: primary and high order aberrations are balanced well we adopt Offner null compensator to test the aspheric surface in the point diffraction interferometer at last. In this paper MTF exceeds diffraction limit an Offner compensator is presented on the base of the third order aberration theory to test concave aspheric surface root-mean-square (RMS) of wave front error /167. The F-number of the system can achieve F/1.64. By the analysis of the process of aspheric surface testing with the designed system the optical construction parameters of which is determined by introducing equal-quantities spherical aberration to compensate all orders of aspheric coefficients. The field of view of the system is 0.02 a loosen distribution of the tolerance was presented based on the accuracy of measuring apparatus. 2009 SPIE.
	Remote chlorophyll-a retrieval in eutrophic inland waters by concentration classification Taihu Lake case study 会议论文 OAI收割 International Conference on Earth Observation Data Processing and Analysis, ICEODPA,, Wuhan, China, December 28, 2008 - December 30,2008 Du, Cong; Wang, Shixin; Zhou, Yi; Yan, Fuli 收藏 \| 浏览/下载：17/0 \| 提交时间：2014/12/07 In order to improve the precision of phytoplankton chlorophyll-a (chla) concentration retrieval this study classified the data into two groups (the high and the low) by chla concentration with the threshold of 50gA&bullL-1. And then build the statistical models for each group. Particularly a modifying factor OSS/TSS was used to unmixing the spectra in the low model to improve the low relationship between spectral reflectance and chla concentrations. As a result the concentration classification model allowed estimation of chla with a root mean square error (RMSE) of 21.12gA&bullL-1 and the determination coefficient (R2) was 0.92 comparing with RMSE of chla estimation was 35.72gA&bullL-1 and R2=0.72 in the traditional model. It shows that concentration classification is a helpful method for accurate remote chla retrieval in eutrophic inland waters. 2008 SPIE.
	The study on the near infrared spectrum technology of sauce component analysis (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China 作者: Li S.; Wang C.; Chen X.; Chen X.; Chen X. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 The author Shangyu Li engages in supervising and inspecting the quality of products. In soy sauce manufacturing quality control of intermediate and final products by many components such as total nitrogen saltless soluble solids nitrogen of amino acids and total acid is demanded. Wet chemistry analytical methods need much labor and time for these analyses. In order to compensate for this problem we used near infrared spectroscopy technology to measure the chemical-composition of soy sauce. In the course of the work a certain amount of soy sauce was collected and was analyzed by wet chemistry analytical methods. The soy sauce was scanned by two kinds of the spectrometer the Fourier Transform near infrared spectrometer (FT-NIR spectrometer) and the filter near infrared spectroscopy analyzer. The near infrared spectroscopy of soy sauce was calibrated with the components of wet chemistry methods by partial least squares regression and stepwise multiple linear regression. The contents of saltless soluble solids total nitrogen total acid and nitrogen of amino acids were predicted by cross validation. The results are compared with the wet chemistry analytical methods. The correlation coefficient and root-mean-square error of prediction (RMSEP) in the better prediction run were found to be 0.961 and 0.206 for total nitrogen 0.913 and 1.215 for saltless soluble solids 0.855 and 0.199 nitrogen of amino acids 0.966 and 0.231 for total acid respectively. The results presented here demonstrate that the NIR spectroscopy technology is promising for fast and reliable determination of major components of soy sauce.
	Fast determination of total ginsenosides content in Ginseng powder by near infrared reflectance spectroscopy (EI CONFERENCE) 会议论文 OAI收割 ICO20: Biomedical Optics, August 21, 2005 - August 26, 2005, Changchun, China 作者: Chen X.-D.; Chen X.-D. 收藏 \| 浏览/下载：15/0 \| 提交时间：2013/03/25 Near infrared (NIR) reflectance spectroscopy was used to develop a fast determination method for total ginsenosides in Ginseng (Panax Ginseng) powder. The spectra were analyzed with multiplicative signal correction (MSC) correlation method. The best correlative spectra region with the total ginsenosides content was 1660 nm1880 nm and 2230nm-2380 nm. The NIR calibration models of ginsenosides were built with multiple linear regression (MLR) principle component regression (PCR) and partial least squares (PLS) regression respectively. The results showed that the calibration model built with PLS combined with MSC and the optimal spectrum region was the best one. The correlation coefficient and the root mean square error of correction validation (RMSEC) of the best calibration model were 0.98 and 0.15% respectively. The optimal spectrum region for calibration was 1204nm-2014nm. The result suggested that using NIR to rapidly determinate the total ginsenosides content in ginseng powder were feasible.