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	The measuring method for low rotational speed with the frequency difference generated by radial gratings (EI CONFERENCE) 会议论文 OAI收割 2012 International Applied Mechanics, Mechatronics Automation Symposium, IAMMAS 2012, September 7, 2012 - September 9, 2012, Shenyang, Liaoning, China Guo W.-l.; Qiao Y.-f. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 The new method has been proposed based on the comparison and analysis of the traditional methods for measuring rotating speed. It can guarantee real-time property with radial gratings at measuring low speed. It is clearly explained that the fundamental principle for measuring rotating speed and characters of the method and presented the constitution of the system hardware and the process flows. (2012) Trans Tech Publications Switzerland.
	Design of a miniature axial flux flywheel motor with PCB winding for nanosatellites (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 Wu J. 收藏 \| 浏览/下载：41/0 \| 提交时间：2013/03/25 This paper presents the design and analysis of an axial flux permanent-magnet (AFPM) machine for nanosatellites application. It is a miniature axial flux surface mounted permanent magnet flywheel motor using a printed circuit board (PCB) stator winding. The PCB stator has simplified the design and construction and avoids unnecessary space since size reduction has become one of the most important aspects of flywheel motor design for nanosatellites. The performances of the machine are estimated by combination method of three-dimensional (3D) electromagnetic finite element analysis (FEA) and approximate theoretical analysis. The back EMF and electromagnetic torque are derived. A comparison between the analysis and experimental measurement results of the prototype machine is also presented. Both simulated and experimental results show that the proposed motor would be an acceptable solution for the nanosatellite applications with advantages such as simple structure and low-cost as multi-layer circuit board production techniques have made the production of printed circuit coils cheaper and easier. 2012 IEEE.
	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.
	Random vibration analysis on the support of strapdown inertial navigation system (EI CONFERENCE) 会议论文 OAI收割 2nd Annual Conference on Electrical and Control Engineering, ICECE 2011, September 16, 2011 - September 18, 2011, Yichang, China 作者: Li M. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 Vibration of the support is an important factor to the accuracy of strapdown inertial navigation. To get vibration characteristics of the support FEM model of the support was created with Ansys and then response characteristics were analyzed on the support under the separated random loads during carrier flight including the phases of subsonic and subsonic. To validate the analysis method wide band random vibration test was done on the points of the support which are used for mounting inertial instruments. The comparison of the analysis and the test data shows that the relative error of analysis result is not more than 13%. According to the two results the support structure was improved. Finally random vibration analysis was carried out on the improved one. The result shows that the acceleration response was largely reduced than before. This research can be a reference of performance improvement of the strapdown inertial support and navigation system precision. 2011 IEEE.
	The research of the accurate measure of static transfer function for the TDI CCD camera (EI CONFERENCE) 会议论文 OAI收割 3rd International Photonics and OptoElectronics Meetings, POEM 2010, November 2, 2010 - November 5, 2010, Wuhan, China Guo-Ning L.; Long-Xu J.; Jian-Yue R.; Wen-Hua W.; Shuang-Li H. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 In the test course of static transfer function of TDI CCD camera because of the influence that gets environmental and artificial etc. factor the value of static transfer function measured at any time is between unceasing fluctuation so make accuracy reduce. To solve this problem a kind of accurate measurement technique of static transfer function is put forward. First before carrying out the measure of static quiet of transfer function the best test point of transfer function of the TDI CCD camera must be determined it is parallel to guarantee the rectangle target surface of parallel optical pipe and camera focal plane maintenance parallel and again guarantee target strip in rectangle target and TDI CCD in camera focal plane maintenance vertical. TDI CCD catches rectangle target image per 1000 lines of target mark image as a measures sample of static transfer function exclude because of atmosphere tremble twisted vague rectangle target mark image retain 500 distinct and steady target mark image as measure sample set. Then calculate the static transfer function of each measure sample respectively take the average of all static quiet transfer function in measure sample set as the static transfer function of camera. Finally the measure of the static transfer function for TDI CCD camera makes error analysis. Experimental results indicate that the value of the static transfer function of TDI CCD camera measured with this kind of method is 0.2923 with before measurement technique comparison the value of static transfer function has raised 0.02 makes the accuracy of the measure of static transfer function have gotten raising.
	Extraction of Microula sikkimensis seed oil and simultaneous analysis of saturated and unsaturated fatty acids by fluorescence detection with reversed-phase HPLC 期刊论文 OAI收割 journal of food composition and analysis, 2010, 卷号: 23, 期号: 1, 页码: 100-106 作者: Cao, Yue; Suo, Yourui 收藏 \| 浏览/下载：64/12 \| 提交时间：2011/12/13 Extraction Microula sikkimensis Hemsl. seed oil Fatty acids High performance liquid chromatography Derivatization Fluorescence detection Method of analysis comparison Food analysis Food composition
	Analysis of a diffractive microlens using the finite-difference time-domain method (EI CONFERENCE) 会议论文 OAI收割作者: Liu Y.; Liu H.; Liu H.; Liu H.; Liu Y. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 The finite-difference time-domain (FDTD) method is used as rigorous electromagnetic analysis model to calculate the field for a diffractive microlens (DML). The FDTD is used for the entire solution rather than using a near- to far-field propagation method to obtain the far-field energy distribution thus all the results are vector based. We derived a formula to calculate the magnitude of electric field which is time dependent and can be used to graphically show the light wave propagation and focusing process through a DML. Both the comparison and the integral methods are presented to obtain wave amplitude in full solution space and the distribution of light energy behind a DML is illustrated based on the wave amplitude. The formula of diffractive efficiency of the DML is derived from a time-averaged Ponyting vector which can indicate the propagation direction of light energy. Application of these formulations in the analysis of a DML example demonstrates the high accuracy and efficiency of our method. 2010 Society of Photo-Optical Instrumentation Engineers.
	Rigorous vector analysis of diffractive microlens by using of finitedifference time-domain method (EI CONFERENCE) 会议论文 OAI收割 2009 International Conference on Optical Instruments and Technology, OIT 2009, October 19, 2009 - October 22, 2009, Shanghai, China 作者: Liu Y.; Liu H.; Liu H.; Liu H.; Liu Y. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 We use finite difference time domain (FDFD) method as rigorous vector analysis model to simulate the focusing process of diffractive microlens (DML). Differing with most analysis model which the near field distributions are calculated by FDTD and then far field are obtained by using of propagation method we obtain the fields in whole computational space by using of FDTD only. The advantages are that all the results are vector based and the computational time is saved greatly. In this paper we present two methods to obtain wave amplitude one is comparison method and the other is integral method. Depending on wave amplitude in the whole computational space one can conveniently obtain distributions of electric field intensity and calculate the time-average Poynting vector. We also present the formulation for calculating diffractive efficiency of DML based on time-average Poynting vector which denotes energy flow. As demonstration a DML is analyzed by using of these algorithms. The time depended graphic results of FDTD show the process of wave propagation. The distribution of electric field intensity illustrates the focusing of the normal incident light. The focus pattern in the focal plane is also show. The diffractive efficiency of the DML is calculated by using of the energy flow method in this paper. The results show the high accuracy and efficiency of the model. 2009 SPIE.