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排序方式: 共有3849条查询结果,搜索用时 15 毫秒
1.
面部运动单元检测旨在让计算机从给定的人脸图像或视频中自动检测需要关注的运动单元目标。经过二十多年的研究,尤其是近年来越来越多的面部运动单元数据库的建立和深度学习的兴起,面部运动单元检测技术发展迅速。首先,阐述了面部运动单元的基本概念,介绍了已有的常用面部运动单元检测数据库,概括了包括预处理、特征提取、分类器学习等步骤在内的传统检测方法;然后针对区域学习、面部运动单元关联学习、弱监督学习等几个关键研究方向进行了系统性的回顾梳理与分析;最后讨论了目前面部运动单元检测研究存在的不足以及未来潜在的发展方向。 相似文献
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3.
Luca Pietrobon Lorenzo Fallarino Andreas Berger Andrey Chuvilin Flix Casanova Luis E. Hueso 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(47):6295-6301
Graphene has been predicted to develop a magnetic moment by proximity effect when placed on a ferromagnetic film, a promise that could open exciting possibilities in the fields of spintronics and magnetic data recording. In this work, the interplay between the magnetoresistance of graphene and the magnetization of an underlying ferromagnetic insulating film is studied in detail. A clear correlation between both magnitudes is observed but through a careful modeling of the magnetization and the weak localization measurements, that such correspondence can be explained by the effects of the magnetic stray fields arising from the ferromagnetic insulator is found. The results emphasize the complexity arising at the interface between magnetic and 2D materials. 相似文献
4.
使用连续小波变换讨论了某些偏微分方程和相应的积分方程之间的关系.使用连续小波变换能够将这些偏微分方程变换成相应的积分方程,这些偏微分方程与相应的积分方程不仅在弱收敛意义下是等价的,而且在范数收敛意义下也是等价的. 相似文献
5.
颜呐 《广东工业大学高等工程教育研究》2007,7(2):78-80
白先勇以弱势的男性和强势的女性作为建构其小说世界的基点。男女角色易位颠覆了男强女弱的传统人物塑造方式,揭示出单个人边缘化生存所不为人知的痛苦。父辈影响、生活经历及其性取向是产生这一特色的根本原因。 相似文献
6.
In this paper,a new method is presented for 3D motion estimation by image region correspondences using stereo cameras.Under the weak perspectivity assumption.we first employ the moment tensor theory (Cyganski and Orr^[11]) to compute the monocular affine transformations relating images taken by the same camera at different time instants and the binocular affine transformations relating images taken by different cameras at the same time instant.We then show that 3D motion can be recovered from these 2D transformations.A space-time fusion strategy is proposed to aim at robust results.No knowledge of point correspondences if requred in the above processes and the computations involved are linear.To find corresponding image regions,new affine invariants,which show stronger invariance,are derived in term of tensor contraction theory.Experiments on real motion images are conducted to verify the proposed method. 相似文献
7.
It has been reported that it is harder to switch to a strong, well-practiced task from a weaker, less-practiced task than vice versa. Three experiments replicated this surprising asymmetry and investigated how it is affected by a reduction in interference between tasks. Experiment 1 progressively delayed the onset of the stimulus attribute associated with the stronger task. Experiments 2 and 3 separated the response sets of the tasks. Both manipulations reduced, without eliminating, interference of the stronger with the weaker task but reversed the asymmetry of switch costs, resulting in a larger cost of switching to the weaker task. The results are interpreted in terms of a model of the interactions between control input, task strength, and task priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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High-T
c
Bi(Pb)-Sr-Ca-Cu-O thin films have been made on single-crystal MgO substrates using high-pressure dc sputtering technique. X-ray studies confirm the crystallinity and highly oriented structure withc-axis perpendicular to the substrate. By optimizing the annealing schedule the formation of the high-T
c
phase is stabilized. The best film exhibited superconducting transition temperature with zero-resistance temperature,T
c(0), as high as 101 K. Temperature dependence ofJ
c
indicates the presence of Josephson-type weak links. 相似文献
10.
Variation of magnetic critical current density (J
mc) and transport critical current density (J
tc) in high magnetic fields at liquid helium temperature were investigated on Sm-Ba-Cu-O: Ag
x
(x=0.0, 0.2, 0.4, and 0.6) superconducting samples prepared by the coprecipitation technique.T
c
and crystallographic parameters remain unaffected by Ag addition. However, bothJ
mc andJ
tc were found to increase on Ag addition. The volume pinning force (F
p) also increased with increase in Ag concentration, resulting in stronger flux line sheer. Microwave-induced d.c. voltage measurement shows a significant reduction of the total number of weak links between the superconducting grains with increasing concentration of Ag, which creates stronger pinning potentials between the boundary of the superconducting intergrains. Hence, the volume pinning force is greatly enhanced by Ag addition, leading to flux line lattice movement which is responsible for highJ
mc andJ
tc. 相似文献