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	A NEW INTEGRAL EQUATION FORMULATION FOR SCATTERING BY PENETRABLE DIFFRACTION GRATINGS 期刊论文 OAI收割 JOURNAL OF COMPUTATIONAL MATHEMATICS, 2018, 卷号: 36, 期号: 1, 页码: 110-127 作者: Zhang, Ruming; Zhang, Bo \| 收藏 \| 浏览/下载：22/0 \| 提交时间：2018/07/30 Scattering problem Transmission condition Periodic interface Diffraction gratings Boundary integral equations Helmholtz equation
	Advanced astigmatism-corrected tandem Wadsworth mounting for small-scale spectral broadband imaging spectrometer (EI CONFERENCE) 会议论文 OAI收割作者: Lin G.-Y. 收藏 \| 浏览/下载：40/0 \| 提交时间：2013/03/25 Tandem gratings of double-dispersion mount make it possible to design an imaging spectrometer for the weak light observation with high spatial resolution high spectral resolution and high optical transmission efficiency. The traditional tandem Wadsworth mounting is originally designed to match the coaxial telescope and large-scale imaging spectrometer. When it is used to connect the off-axis telescope such as off-axis parabolic mirror it presents lower imaging quality than to connect the coaxial telescope. It may also introduce interference among the detector and the optical elements as it is applied to the short focal length and small-scale spectrometer in a close volume by satellite. An advanced tandem Wadsworth mounting has been investigated to deal with the situation. The Wadsworth astigmatism-corrected mounting condition for which is expressed as the distance between the second concave grating and the imaging plane is calculated. Then the optimum arrangement for the first plane grating and the second concave grating which make the anterior Wadsworth condition fulfilling each wavelength is analyzed by the geometric and first order differential calculation. These two arrangements comprise the advanced Wadsworth mounting condition. The spectral resolution has also been calculated by these conditions. An example designed by the optimum theory proves that the advanced tandem Wadsworth mounting performs excellently in spectral broadband. 2012 Optical Society of America.
	Design and analysis of power system of micro-electromechanical actuator (EI CONFERENCE) 会议论文 OAI收割 2010 2nd International Conference on Industrial Mechatronics and Automation, ICIMA 2010, May 30, 2010 - May 31, 2010, Wuhan, China 作者: Zhang J.; Zhang J.; Zhang J. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 In order to apply the electromechanical actuator to tactical mini-missiles maximum rotational speed of output shafts is greater than 250/s. Test results basically correspond to the requirement of technical indexes. It is proved that this analysis and design method is congruent with the design of micro-electromechanical actuators this paper researches on the key technology such as load-bearing ability the system bandwidth can reach 25.3Hz on the condition of no load and 23.4Hz on the condition of load thus the method is feasible. 2010 IEEE. rapidity and miniaturization of the micro-electromechanical actuator power system based on the ball screw. First according to specific technical indexes the power electromechanical time constant and the size of the motors are screened originally through theoretical analysis. Finally based on the characteristics of ball screw transmission load locus of the micro-electromechanical actuator dynamic system is theoretically analyzed and the optimum speed ratio is determined through parameter optimization. The results of the double closed loop controlled test on the principle prototype show: the system can operate normally with 2.5N.m hinge moment
	Study of unequal error protection method based on JPEG2000 for surveyingmapping image (EI CONFERENCE) 会议论文 OAI收割 International Conference on Computer Science and Software Engineering, CSSE 2008, December 12, 2008 - December 14, 2008, Wuhan, Hubei, China Yao Q.; Cao M. 收藏 \| 浏览/下载：175/0 \| 提交时间：2013/03/25 On aviation mapping compression image maybe not decode because of wireless transmission interference. UEP(Unequal Error Protection) scheme is put forward about layer and block structure of JPEG2000 image compression method flexibly enhances local reconfigurable image's quality which is in favor of identifier in the region of interest. 2008 IEEE. and realizes three degrees UEP of data block data header image data via various degrees correction-coding under the condition of obstruct naked and shade. BCH RS and Hamming coding are simulated and image decoding success rate and image's quality are analyzed according to different coding and ROI (Region of Interest) in the Gaussian white noise model and rayleigh fading model. Results shows that the method we putted forward roughly improves decoding success rate at the same time almost not increasing bandwidth
	Optical characteristic of ion beam sputter deposited aluminum thin films (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging, ISPDI 2007: Optoelectronic System Design, Manufacturing, and Testings, September 9, 2007 - September 12, 2007, Beijing, China 作者: Yang H.; Liu L.; Liu L. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 Aluminum is a typical active metal very easy to oxidize. An oxide surface layer of about 2-6nm quickly formed in air which adds difficulty to the optical constants determination. An ex-situ method is used to determine the optical constants of aluminum thin films. First Second Third alumina (Al2O3) thin film is deposited by ion beam sputter deposition. The optical constants and thickness are determined by spectral ellipsoemtry (SE). The thickness is verified by grazing x-ray reflection (GXRR) fitting method Al thin film with an Al2O3 cap layer on top is deposited. This cap layer is of the same deposition condition with the first step. By fitting the GXRR spectra based on the acquired structure information the structure information (the thickness of the aluminum and the cap layer the ellipsometric spectra are fitted. The optical constants of the aluminum layer are extracted with the aid of the Drude model. Finally surface roughness and the diffusion between Al-Al2O 3) is obtained an induced transmission filter (ITF) is designed and deposited.
	Design of optical elements for imaging the earth's plasmasphere (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging, ISPDI 2007: Optoelectronic System Design, Manufacturing, and Testings, September 9, 2007 - September 12, 2007, Beijing, China 作者: Chen B.; Chen B.; Wang X.-K. 收藏 \| 浏览/下载：38/0 \| 提交时间：2013/03/25 Studying the distribution of He+ in Earth's plasmasphere by detecting its resonantly-scattered emission at 304A will record the structure and dynamics of the cold plasma in Earth's plasmasphere on a global scale. EUV imaging systems usually utilizes near normal incidence optics including multilayer mirror and filter. In this paper the space condition of the Earth's plasmasphere to confirm the expected performance of mirror and filter for this task were analyzed and some guidelines for the design of the optical elements were introduced. In order to achieve higher response at 304A and reduce 584A radiation for the optical system a new multilayer coating of Mo/Si with UOx (x=2-3) was developed and it is indicated that promising filter material is Al/C with a nickel mesh. In addition we compute the reflectance of multilayer mirror based on optical constants and the transmission of the filter based on atomic scattering factor. The results show the multilayer mirror has high reflectance of 26.27% at 304 Aand low reflectance of 0.60% at 584A. Finally the conversion efficiency of mirror coupled with filter is 6.88% at 304A and 0.01% at 584 A.
	OPTIMIZED SCHWARZ METHODS WITH ROBIN TRANSMISSION CONDITIONS FOR PARABOLIC PROBLEMS 期刊论文 OAI收割 SIAM JOURNAL ON SCIENTIFIC COMPUTING, 2008, 卷号: 31, 期号: 1, 页码: 608-623 作者: Qin, Lizhen; Xu, Xuejun \| 收藏 \| 浏览/下载：27/0 \| 提交时间：2018/07/30 parabolic problem nonconforming finite elements nonoverlapping domain decomposition Robin transmission condition convergence rate optimal parameter