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	A New Equation for Deriving Vegetation Phenophase from Time Series of Leaf Area Index (LAI) Data 期刊论文 OAI收割 REMOTE SENSING, 2014, 卷号: 6, 期号: 6, 页码: 5650-5670 作者: Fang, Shifeng; Chen, Baozhang 收藏 \| 浏览/下载：41/0 \| 提交时间：2014/08/26 vegetation phenology leaf area index (LAI) S-curve function asymmetric Gaussian function logistic function
	A New Equation for Deriving Vegetation Phenophase from Time Series of Leaf Area Index (LAI) Data SCI/SSCI论文 OAI收割 2014 Che M. L.; Chen B. Z.; Zhang H. F.; Fang S. F.; Xu G.; Lin X. F.; Wang Y. C. 收藏 \| 浏览/下载：31/0 \| 提交时间：2014/12/24 vegetation phenology leaf area index (LAI) S-curve function asymmetric Gaussian function logistic function fall foliage coloration land-surface phenology spring phenology growing-season tibetan plateau activity trends satellite data real-time dynamics modis
	Comparison of radiation temperature measurement precision between middlewave and longwave thermal-imaging systems (EI CONFERENCE) 会议论文 OAI收割 2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China 作者: Sun Z. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 A comparison study on temperature measurement precision between middlewave 3-5m and longwave 8-12m measuring thermal imaging systems has been conducted. The study was limited to systems working in indoor conditions and the target's temperature is in the range of 270K900K. First the Disturb Resisting Function (DRF) of infrared systems is deduced. On the base of DRF curve we find that the middlewave infrared system get the smaller influences under the same size disturb compared with the longwave system. A theory of the influence of target's physical characteristic and measurement conditions on the accuracy of temperature measurements has been developed. On the basis of the developed formulas an analysis of the influence of signal disturbances (because of incorrectly assumed emissivity limited transmittance of the atmosphere radiation reflected by the object and shift of optics radiation) on the accuracy of temperature measurement has been made. It has been found that the middlewave systems in typical temperature range offer generally better accuracy in temperature measurement than the longwave ones do. 2012 IEEE.
	Graph fitting test method for the interpolation error of Moire fringe (EI CONFERENCE) 会议论文 OAI收割 9th International Conference on Electronic Measurement and Instruments, ICEMI 2009, August 16, 2009 - August 19, 2009, Beijing, China 作者: Sun Y.; Sun Y. 收藏 \| 浏览/下载：40/0 \| 提交时间：2013/03/25 In order to realize the fast test for the interpolation error the graph fitting test method for the interpolation error of Moire fringe is put forward in this paper. Firstly the triangular wave Moire fringe photoelectric signal of the encoder whose phase difference is 90 are sampled to get the Lissajous graph of the two signals. Secondly the single wave represented by the founded subsection function is used to fit the practical Moire fringe Lissajous graph. Then the fitting result is tested to verify whether it satisfies the accuracy requirement. Lastly the founded subsection function instead of the practical wave function is used to calculate the interpolation error. Using the graph fitting method to sample the Moire fringe single of 15-bits photoelectric encoder to get the interpolation error curve the tested maximum interpolation error is 70" and the minimum error is - 69". Comparing with the interpolation error which is received from traditional test method the change trend of the interpolation error curve is similar and peak-peak value is almost equality. The results of experiment indicate that: the equipment is convenient and the examination method is efficient and feasible. The measure speed is fast and the manifestation result is intuitionistic. The system can be used in the working field. The method can avoid the speed influence and realize the dynamic interpolation error measure which is significant for the research of encoder's dynamic accuracy characteristics. 2009 IEEE.