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浏览/检索结果: 共5条，第1-5条 帮助 限定条件 发表日期：2009     已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 1D-KBA microscope using double-periodic multilayer (EI CONFERENCE) 会议论文 Advances in X-Ray/EUV Optics and Components IV, August 3, 2009 - August 5, 2009, San Diego, CA, United states Mu B.; Wang Z.; Yi S.; Zhu J.; Wang X.; Jiang L.; Huang Q.; Bai Y. 收藏  |  浏览/下载：9/0  |  提交时间：2013/03/25 To study the action of shock wave in CH target  one-dimensional grazing incidence KBA microscope for 4.75keV energy was set up. Because of strong absorption in air  4.75keV energy microscope can just work in vacuum. Accordingly  the alignment and assemblage will be very complicated and difficult. A special multilayer method  using double periodic multilayer  was proposed to solve this problem. This multilayer has high reflectivity not only for 4.75keV X-rays but also for 8keV X-rays at the same grazing incidence angle. It means 1D-KBA microscope has the same light trace for different working energies. Therefore  we can implement the alignment and assembly of 4.75keV system by the help of 8keV X-rays. Because 8keV X-rays is very easy produced by X-ray tube and has strong transmittability in air  the alignment and assemblage process became relatively easy. By now  we have finished the alignment experiment at 8keV and obtained imaging results. The performance is about 2-3m resolution in 250m field of view. It is coincide with the calculation. 2009 SPIE.   Multiresolution animated models generation based on deformation distance analysis (EI CONFERENCE) 会议论文 2009 International Conference on Computer Modeling and Simulation, ICCMS 2009, February 20, 2009 - February 22, 2009, Macau, China Shixue Z.; Enhua W. 收藏  |  浏览/下载：59/0  |  提交时间：2013/03/25 In computer graphics  animated models have been widely used to represent time-varying data. Reducing the models complexly is a common way to overcome the rendering limitations. In this paper  2009 IEEE.  we propose an efficient method for generating multiresolution animated models based on deformation distance analysis. Our method obtains different LOD models by performing iterative edge contraction operations. We use deformation distance to analysis the deformation degree of the triangle planes during the whole animation  and define a deformation weight to be added to the aggregated edge contraction cost. Thus features in areas with large deformation can be preserved well. Besides  we propose a mesh optimization method for dynamic model sequence  which can efficiently improve the temporal coherence and reduce visual artifacts between adjacent frames. The results show our approach is efficient  easy to implement  and good quality animated approximations with well-preserved fine details can be generated at any given frame. copy   Estimation algorithm of mobile OFDM CFOs based on step-size (EI CONFERENCE) 会议论文 2009 International Conference on Information Engineering and Computer Science, ICIECS 2009, December 19, 2009 - December 20, 2009, Wuhan, China Lin L.; Qiao Y.-F.; Su W.-X. 收藏  |  浏览/下载：20/0  |  提交时间：2013/03/25 In order to maintain orthogonality among subcarriers for mobile OFDM  a CFOs step-size estimation model is established to avoid severe performance degradation caused by ICI  and algorithmic stability  step-size parameter  the error of CFOs estimate and etc are investigated. First  after an averaging window algorithm is introduced  the mathematic model of step-size estimation algorithm is obtained through step-size parameter and time-varying CFOs. Then  based on the results of MATLAB simulation  the determination of step-size parameter  the advantages of step-size algorithm and precision are discussed. Finally  time sequence plots of added CP  interleaver and subcarrier modulation with VHDL are presented. Experimental results indicate that the maximum of CFOs errors is 0.00987 in 3 variance interval  when mobile velocity is 400 km/h  according with verdicted principle that in order for the ICI effects to be negligible  the error of CFOs estimation must be accurate within 1-2% of the subcarrier spacing  and programs can correctly implement on circuit board. 2009 IEEE.   An improved method for generating multiresolution animation models (EI CONFERENCE) 会议论文 2009 11th IEEE International Conference on Computer-Aided Design and Computer Graphics, CAD/Graphics 2009, August 19, 2009 - August 21, 2009, Huangshan, China Zhang S.; Wu E. 收藏  |  浏览/下载：35/0  |  提交时间：2013/03/25 In computer graphics  animated models are widely used to represent time-varying data. In this paper  we propose an improved method to generate multiresolution animation models. We use a curvature sensitive quadric error metric (QEM) criterion as our basic measurement  which can preserve local features on the surface. We append a deformation weight to the aggregated edge contraction cost for the whole animation to preserve areas with large deformation. At last  we introduce a mesh optimization method to deal with the animation sequence  which can efficiently improve the temporal coherence and reduce visual artifacts. The results show our approach is efficient  easy to implement  and good quality progressive animation models can be generated at any level of detail. 2009 IEEE.   Application of multi-sensors parallel fusion system in photoelectric tracing (EI CONFERENCE) 会议论文 2008 International Conference on Optical Instruments and Technology: Optoelectronic Measurement Technology and Applications, November 16, 2008 - November 19, 2008, Beijing, China Cheng G.-Y.; Cai S.; Gao H.-B.; Zhang S.-M.; Qiao Y.-F. 收藏  |  浏览/下载：15/0  |  提交时间：2013/03/25 To solve the real-time and reliability problem of tracking servo-control system in optoelectronic theodolite  a multisensors parallel processing system was proposed. Misdistances of three different wavebands were imported into system  and then prediction was done in DSP1 to get the actual position information. Data fusion was accomplished in PPGA imported by multi channel buffer serial port. The compound position information was used to control the theodolite. The results were compared with external guide data in DSP2 to implement correction of above calculation  and then were imported to epistemic machine through PXI interface. The simulation experiment of each calculation unit showed that this system could solve the real-time problem of feature level data fusion. The simulation result showed that the system can satisfy the real-time requirement with 1.25ms in theodolite with three imaging systems  while sampling frequency of photoelectric encoder was 800 Hz. 2009 SPIE.