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由于传统的子空间方法易于丢失图像目标的二维特性,为此本文提出了一种新颖的自适应目标跟踪算法,通过张量的方式建立目标的外观模型——张量子空间,利用在线学习的方法更新其外观模型,同时,利用目标仿射运动的先验信息,通过粒子滤波自适应地跟踪运动目标,并将获得的最优目标观测作为新数据反馈回子空间更新.此外,为了保证子空间更新能获得精确且紧致的目标子空间表达,引入动态部分函数滤除样本野点.实验结果表明,本文提出的自适应目标跟踪方法具有较强的鲁棒性,对于存在姿态变化、短时遮挡和光照变化等情况下均可有效地跟踪目标. 相似文献
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采用在Fe:LiNbO3中掺入了铟离子生长的双掺杂InFe:LiNbO3晶体,以波长为1064 nm的近红外会聚光束作为记录光源,通过数字观测装置,对比研究了铟离子掺入前后Fe:LiNbO3晶体和InFe:LiNbO3晶体的光折变性能。实验研究结果表明,铟离子掺入后晶体的光折变响应速度和抗光折变能力明显提高,饱和折射率变化量降低。初步分析认为,InFe:LiNbO3晶体光折变性能的增强是由于掺入的铟离子取代了部分光折变敏感中心,降低了光敏中心的数量,导致晶体光电导增大,响应时间随之缩短。 相似文献
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First-principles investigation of N-Ag co-doping effect on electronic properties in p-type ZnO 下载免费PDF全文
The geometric structure, band structure and density of
states of pure, Ag-doped, N-doped, and N--Ag codoped wurtzite ZnO
have been investigated by the first-principles ultra-soft
pseudopotential method based on the density functional theory. The
calculated results show that the carrier concentration is increased
in the ZnO crystal codoped by N and Ag, and the codoped structure is
stable and is more in favour of the formation of p-type ZnO. 相似文献
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This paper studies the type-I phase-matched second harmonic generation using 25-fs input laser pulses in a thick BBO crystal.The harmonic signal exhibits a narrow spectrum bandwidth,even though the input pulse has a broad bandwidth.The energy transfer efficiency and modulation of the fundamental spectrum are investigated. 相似文献
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由于传统的子空间方法易于丢失图像目标的二维特性,为此本文提出了一种新颖的自适应目标跟踪算法,通过张量的方式建立目标的外观模型——张量子空间,利用在线学习的方法更新其外观模型,同时,利用目标仿射运动的先验信息,通过粒子滤波自适应地跟踪运动目标,并将获得的最优目标观测作为新数据反馈回子空间更新.此外,为了保证子空间更新能获得精确且紧致的目标子空间表达,引入动态部分函数滤除样本野点.实验结果表明,本文提出的自适应目标跟踪方法具有较强的鲁棒性,对于存在姿态变化、短时遮挡和光照变化等情况下均可有效地跟踪目标. 相似文献
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One-dimensional(ID) In2O3(ZnO)m superlattice nanobelts are synthesized by a chemical vapor deposition method.The formation of the In2O3(ZnO)m superlattice is verified by the high-resolution transmission electron microscopy images.The typical zigzag boundaries could be clearly observed.An additional peak at 614 cm-1 is found in the Raman spectrum,which may correspond to the superlattice structure.The study about the electrical transport properties reveals that the In2O3(ZnO)m nanobelts exhibit peculiar nonlinear I-V characteristics even under the Ohmic contact measurement condition,which are different from the Ohmic behaviors of the In-doped ZnO nanobelts.The photoelectrical measurements show the differences in the photocurrent property between them,and their transport mechanisms are also discussed. 相似文献