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Boundary value problems of fractional Fokker-Planck equations 期刊论文 OAI收割
COMPUTERS & MATHEMATICS WITH APPLICATIONS, 2017, 卷号: 73, 期号: 6, 页码: 959-969
作者: Aleroev, Temirkhan S.; Aleroeva, Hedi T.; Huang, Jianfei; Tamm, Mikhail V.; Tang, Yifa

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收藏 | 浏览/下载：28/0 | 提交时间：2018/07/30

Boundary value problems Fractional Fokker-Planck equations The Fourier method Caputo derivative operator

Improved method of target detection on optoelectronic hybrid joint transform correlator in cluttered scences (EI CONFERENCE) 会议论文 OAI收割
2011 3rd International Conference on Mechanical and Electronics Engineering, ICMEE 2011, September 23, 2011 - September 25, 2011, Hefei, China
作者: Yang L.; Yang L.

收藏 | 浏览/下载：22/0 | 提交时间：2013/03/25

A classical joint transform correlator (JTC) usually yields large correlation sidelobes as well as a large correlation peak width strong zero-order peak and low diffraction efficiency which make the detection ability of JTC lower. To overcome these difficulties firstly a joint power spectrum (JPS) subtraction technique in Fourier plane was proposed where reference image power spectrum and object image power spectrum are subtracted from the JPS before inverse Fourier-transform operation it is obvious that the modified JPS removes the zero-order term. Secondly a fringe-adjusted filter (FAF) was presented to suppress sidelobes and noises. The modified JPS is multiplied by a FAF before the inverse Fourier-transform operation to obtain the cross-correlation peak. Computer simulations demonstrated the improved method can obviously remove zero-order diffraction and effectively suppress the sidelobes and noises compared with classic JTC and then improve the detection ability for JTC. Experimental results presented the sharp correlation peak and also confirmed the method effectiveness. (2012) Trans Tech Publications Switzerland.

Correction of baseline drifts due to the pressure changes between attenuated total reflection prism and human skin for noninvasive blood glucose sensing with Fourier Transform infrared spectroscopy (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Smart Materials and Nanotechnology in Engineering, SMNE 2011, September 17, 2011 - September 18, 2011, Wuhan, China
作者: Wang D.

收藏 | 浏览/下载：48/0 | 提交时间：2013/03/25

For noninvasive blood sensing with attenuated total reflection (ATR)-Fourier Transform infrared spectroscopy(FTIR) the baseline of spectra human skin will drift because of the exitence of pressure changes between ATR prism and human skin. To correct the baseline drifts In the paper the fingertips spectra in mid-infrared were recorded under the special conditions. A line equation was calculated using the last 14 spectra coupled with the linear regression analysis between the absorbance spectra at the 1035cm-1 and the 950cm-1. And the corrected absorption intensities after the removal of the baseline drifts can be applied for the quantification of glucose concentrations in blood easily with the given method in the paper. (2012) Trans Tech Publications Switzerland.

Space camera dynamic image quality measurement and evaluation (EI CONFERENCE) 会议论文 OAI收割
3rd International Conference on Measuring Technology and Mechatronics Automation, ICMTMA 2011, January 6, 2011 - January 7, 2011, Shanghai, China
作者: Zhang X.; Zhang X.; Zhang X.

收藏 | 浏览/下载：21/0 | 提交时间：2013/03/25

By using analysis of the infinity image of the space camera we intend to obtain the curve of the dynamic modulation transfer function. We extract the pixel gray values at the image edge which distribute as a knife-edge function and make differential calculation and Fourier transformation of it and then we can obtain the dynamic MTF curve of the optical system. The value of the curve at the Nyquist frequency is the most important parameter that reflects the image quality. We add push-scanning imaging and environmental effects to the static MTF of space camera and compare the MTF value with the dynamic MTF at Nyquist frequency. The comparison result can help us verify the accuracy of the calculating results and the feasibility of our method. (2011) Trans Tech Publications.

Design and demonstration of micro multi-step mirrors and light source in micro FTIR (EI CONFERENCE) 会议论文 OAI收割
6th IEEE International Conference on Nano/Micro Engineered and Molecular Systems, NEMS 2011, February 20, 2011 - February 23, 2011, Kaohsiung, Taiwan
Liang Z.; Fu J.; Feng C.; Liang J.

收藏 | 浏览/下载：43/0 | 提交时间：2013/03/25

To obtain high resolution high signal-to-noise ratio (SNR) high reliability and real time in wide spectral range we study the space modulation Micro Fourier Transform Spectrometer (FTS) based on multi-step mirrors covering the spectral range of 3-5m and 8-12 m in theory and experiment. The influences of spectrum reconstruction caused by the diffraction and extended light source in Fourier Transform Infrared Spectrometer (FTIR) are analyzed. A method to reduce the noises in spectrum reconstruction and the relationship between coherent intensity and solid angle of light source are discussed. An extended light source with suitable size is chosen considering the requirement of SNR and spectrum resolving power in the optical design. Furthermore the fabrication of micro multi-step mirrors which is the core part of FTS is investigated. Three methods for fabricating multi-step micro mirrors are demonstrated. 2011 IEEE.

The movement estimation of target and background by fourier phase spectrum difference (EI CONFERENCE) 会议论文 OAI收割
2010 6th International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM 2010, September 23, 2010 - September 25, 2010, Chengdu, China
作者: Zhang X.; Zhang X.; Zhang X.; Wang J.; Zhang S.

收藏 | 浏览/下载：19/0 | 提交时间：2013/03/25

An algorithm for estimating displacement of the moving target and background by shift theory of Fourier transform is presented. According to the relation between the change and the Fourier transform of image sequence the method employs the displacement value of the moving target and background by the difference of Fourier phase spectrum. The algorithm estimates the movements from the whole field of the image with excellent global property. This paper provides the calculus and experiments of the algorithm which show the accuracy of 1 pixel. 2010 IEEE.

Chirp estimation of PZT for integrating-bucket method (EI CONFERENCE) 会议论文 OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China
作者: Zhang J.; Liu W.; Zhang J.; Zhang J.

收藏 | 浏览/下载：26/0 | 提交时间：2013/03/25

The nonlinear response of the PZT for the integrating bucket method is studied by our proposed method: discrete chirp Fourier transform (DCFT) and maximum likelihood estimation (MLE) techniques for the integrating bucket method. Based on the signal processing theory the intensity obtained from CCD is processed by the DCFT and thus nonlinear response and chirp coefficient of the PZT can be coarsely estimated. This is followed by the MLE method in which an iterative optimization process is complemented for accurately estimating the nonlinear response and chirp coefficient of the PZT. One key advantage of the proposed method is that not only the nonlinear response and chirp coefficient of the PZT can be acquired but also initial phase acquired. Our method is tested by simulating conditions under which a certain magnitude of nonlinearity is assumed. Nonlinear response attained by the DCFT is compared to that attained by the MLE and a difference between the actual nonlinear response of the PZT and our accurate estimation by the proposed method is revealed. Several factors that will have influence on the nonlinear response of the PZT are discussed. 2010 Copyright SPIE - The International Society for Optical Engineering.

Micro assembled fourier transform spectrometer (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
作者: Liang J.-Q.; Zhang J.; Zhang J.; Zhang J.; Wang B.

收藏 | 浏览/下载：29/0 | 提交时间：2013/03/25

With the trend of minimization of Fourier transform spectrometer (FTS) which is particularly pronounced in many applications a model of a micro FTS with no moving parts is proposed and analyzed. During analyzng the gradients which mainly introduce phase error are accounted. Based on these assumptions and the improved Mertz phase correcting method the spectrum of signal is simulated with real extended light source. The resolution can be up to 3.43nm@800nm with high signal-to-noise ratio (SNR) limiting resolving ability 6.8dB. In addition the fabrication method of components are illuminated and demonstrated which can not only make it bear some advantages over conventional micro dispersive spectrometers but also afford some new concepts on the design of spectrometers with improved performance. 2009 SPIE.

Correction method for detection of the frequencies of railway fsk signals (EI CONFERENCE) 会议论文 OAI收割
2008 9th International Conference on Signal Processing, ICSP 2008, October 26, 2008 - October 29, 2008, Beijing, China
作者: Yu J.

收藏 | 浏览/下载：63/0 | 提交时间：2013/03/25

In order to acquire the information of railway binary frequency-shift keying signals which include upper/down side frequencies and base low-frequency with high-accuracy a novel frequency detection algorithm for France UM-71 system is proposed. Combining fast Fourier transform with the ratio correction method the carrier frequency and the base frequency are obtained. Furthermore the hardware consumption has been decreased. And it possesses the advantage of simple algorithm and fast operation speed. Comparing with the detection of the base frequency the upper/down side frequency of railway signal is more difficult. Based on spectrum analysis and the spectrum correction a new method which adopts the sliding window is put forward in this paper. The absolute differences between the upper side frequencies and the down side frequencies obtained are regarded as the criterion for judgment. Then the set of data in which the maximum absolute value is is to be the result of the upper/down side frequency. Because the sliding window will go through every stage when the upper/down side frequency changes therefore it is not sensitive enough to the position of data which need to be transformed. Using the method mentioned above the experiment results show that the accuracy requirement of the side frequency is satisfied well. 2008 IEEE.

The cell thickness and twist angle measurement of twist nematic liquid crystal cell by rotation of a quarter-wave plate using fourier analysis method (EI CONFERENCE) 会议论文 OAI收割
Asia Display 2007, AD'07, March 12, 2007 - March 16, 2007, Shanghai, China
Cui H.-Q.; Ling Z.-H.

收藏 | 浏览/下载：25/0 | 提交时间：2013/03/25

Proposed a new method of determining the cell thickness and the twist angle of twisted nematic liquid crystal cells a quarter-wave plate was inserted between the liquid crystal cell and the analyzer a stepper motor rotated the Retarder by 360 and measured the light intensity of every modulated point solved the stokes parameters of polarization light exiting from the liquid crystal cell using Fourier analysis method thereby determining the cell thickness and the twist angle. Experiments indicated that it is suitable for measuring the low-cell-gap accurately. In addition it also can be applied to the measurement of the cell thickness and twist angle of single polarizer reflected liquid crystal cell.