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	A rigorous and unified mass lumping scheme for higher-order elements 期刊论文 OAI收割 COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING, 2017, 卷号: 319, 页码: 491-514 作者: Sivaselvan, M. V.; Yang, Yongtao; Zheng, Hong \| 收藏 \| 浏览/下载：28/0 \| 提交时间：2018/06/05 Lumped mass matrices High-order elements Dynamic analysis Finite element method Manifolds
	(CIP)-I-0 Methods for the Transmission Eigenvalue Problem 期刊论文 OAI收割 JOURNAL OF SCIENTIFIC COMPUTING, 2016, 卷号: 68, 期号: 1, 页码: 326-338 作者: Geng, Hongrui; Ji, Xia; Sun, Jiguang; Xu, Liwei \| 收藏 \| 浏览/下载：21/0 \| 提交时间：2018/07/30 Transmission eigenvalues High order eigenvalue problem Discontinuous Galerkin method Lagrange elements
	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.
	A new numerical method for BLT forward problem based on high-order finite elements 期刊论文 OAI收割 COMMUNICATIONS IN NUMERICAL METHODS IN ENGINEERING, 2009, 卷号: 25, 期号: 6, 页码: 667-681 作者: Hou, Yanbin; Tian, Jie; Wu, Yan; Liang, Jimin; He, Xiaowei 收藏 \| 浏览/下载：18/0 \| 提交时间：2015/08/12 molecular imaging bioluminescence tomography forward problem high-order finite elements diffusion approximation
	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.
	Packaging technology of polymer/Si arrayed waveguide grating and their environmental stability (EI CONFERENCE) 会议论文 OAI收割 2005 6th International Conference on Electronics Packaging Technology, August 30, 2005 - September 2, 2005, Dameisha, Shenzhen, China 作者: Zhang Y.; Zhang X.; Zhang X.; Zhang X.; Wang F. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 Future optical communication systems will use more of the exceptional high bandwidth of optical fiber. Wavelength division multiplexing (WDM) systems are well suited to transport terabits of information via the fiber[1]. Multiplexers/ demultiplexers (MUX/DEMUX) are essential components for dense WDM systems. Several different kinds of multiplexer types have been developed in the past: (a) interference filters (b) fiber gratings and (c) planar lightwave circuit (PLC) MUX/DEMUXers[2 3]. The planar fabrication process of the last mentioned PLCs allows the realization of high performance filters with a large number of wavelength channels. Further an integration with other optical elements seems to be possible. Arrayed waveguide gratings (AWG) are a special kind of PLC-MUX/DEMUXers which are very attractive components for WDM systems because of their great flexibility in filter design[4 5]. Basically an AWG is an optical spectrograph built in planar waveguide technique. Typically AWGs works in a high grating order (50-250). For AWG multiplexer applications in communications systems a precise wavelength controllability and wavelength stability with long term is demanded. Recently a polymeric (especially fluorinated polymer with low optical absorption loss in the infrared region) AWG has attracted much attention because of its easy fabrication low cost possibility and a potential of integration with other polymer devices[6]. Standard AWGs however show a change of center wavelength with temperature. A method to prevent this temperature drift is to package the AWG together with a temperature controller in order to tune and fix the desired filter-wavelength. In this paper a 32-channel AWG was fabricated using a cross-linkable fluorinated poly (ether ether ketone) (FPEEK) its package technology and environmental stability were also discussed. 2005 IEEE.