1,137 research outputs found
Automatic landmark annotation and dense correspondence registration for 3D human facial images
Dense surface registration of three-dimensional (3D) human facial images
holds great potential for studies of human trait diversity, disease genetics,
and forensics. Non-rigid registration is particularly useful for establishing
dense anatomical correspondences between faces. Here we describe a novel
non-rigid registration method for fully automatic 3D facial image mapping. This
method comprises two steps: first, seventeen facial landmarks are automatically
annotated, mainly via PCA-based feature recognition following 3D-to-2D data
transformation. Second, an efficient thin-plate spline (TPS) protocol is used
to establish the dense anatomical correspondence between facial images, under
the guidance of the predefined landmarks. We demonstrate that this method is
robust and highly accurate, even for different ethnicities. The average face is
calculated for individuals of Han Chinese and Uyghur origins. While fully
automatic and computationally efficient, this method enables high-throughput
analysis of human facial feature variation.Comment: 33 pages, 6 figures, 1 tabl
Quantum anomalous vortex and Majorana zero mode in iron-based superconductor Fe(Te,Se)
In topological insulators doped with magnetic ions, spin-orbit coupling and
ferromagnetism give rise to the quantum anomalous Hall effect. Here we show
that in s-wave superconductors with strong spin-orbit coupling, magnetic
impurity ions can generate topological vortices in the absence of external
magnetic fields. Such vortices, dubbed quantum anomalous vortices, support
robust Majorana zero-energy modes when superconductivity is induced in the
topological surface states. We demonstrate that the zero-energy bound states
observed in Fe(Te,Se) superconductors are possible realizations of the Majorana
zero modes in quantum anomalous vortices produced by the interstitial magnetic
Fe. The quantum anomalous vortex matter not only advances fundamental
understandings of topological defect excitations of Cooper pairing, but also
provides new and advantageous platforms for manipulating Majorana zero modes in
quantum computing.Comment: final version, 8 pages, 3 figures + supplemental materia
Dynamics of quantum coherence in Bell-diagonal states under Markovian channels
We study the curves of coherence for the Bell-diagonal states including
-norm of coherence and relative entropy of coherence under the Markovian
channels in the first subsystem once. For a special Bell-diagonal state under
bit-phase flip channel, we find frozen coherence under norm occurs, but
relative entropy of coherence decrease. It illustrates that the occurrence of
frozen coherence depends on the type of the measure of coherence. We study the
coherence evolution of Bell-diagonal states under Markovian channels in the
first subsystem times and find coherence under depolarizing channel
decreases initially then increases for small and tend to zero for large
. We discuss the dynamics of coherence of the Bell-diagonal state under two
independent same type local Markovian channels. We depict the dynamic behaviors
of relative entropy of coherence for Bell-diagonal state under the bi-side
different Markovian channel. We depict the dynamic behaviors of relative
entropy of coherence for Bell-diagonal state under the bi-side different
Markovian channel.Comment: 13 pages, 17 figure
永磁悬浮转子在心脏泵和其它旋转机械中达到稳定平衡的方法
Permanent maglev rotator in a rotary machine could be stabilized according to the author’s experiences, by use of a non-PM (permanent magnetic) force acting together with the PM force, and a non-PM bearing functioning together with the PM bearing, or a so-called gyro-effect which can stabilize all rotators including permanent maglev rotator. This paper presents both axially and radially driven permanent maglev centrifugal heart pumps, as well as a permanent maglev turbine machine and an industrially used permanent maglev centrifugal pump. In all this devices permanent maglev rotators achieve stable equilibrium by different approaches described in detail. Finally, the principle exhibition of gyro-effect and the route chart to stabilization of permanent maglev rotator are presented.根据作者的经验,在包含永磁轴承支承的旋转体的系统中,通过引入一个非永磁力和永磁力共同作用,或利用一个非永磁轴承和永磁轴承共同作用,以及利用一个所谓的能够使包括永磁悬浮转子在内的所有转子稳定的陀螺效应,是能够使永磁悬浮转子在心脏泵及其它旋转机械中达到稳定平衡的。这篇文章不但呈现了轴向和径向驱动的两种永磁悬浮离心式心脏泵,而且还包括永磁悬浮透平机和工业上使用的永磁悬浮离心泵。在所有这些装置中,永磁悬浮转子通过不同的方式达到稳定平衡。文章最后展示陀螺效应的基本原理并提出永磁悬浮转子达到稳定的路线图。由于百多年来学界普遍认为永磁悬浮不能稳定,本文的结果可能将开启一个永磁悬浮旋转机械研究和应用的新纪元
Lightweight Design of Large and Small Chain Wheels of University Formula Racing Car Transmission System Based on CAD Technology
The achievements of the Chinese college students’ equation competition have already represented the strength of a college automobile field, and more and more auto related colleges and universities have paid more and more attention to this event. The vehicle drive system has a great influence on the power of the car, and the research of the light quantization in the power transmission system has become a hot spot of concern in the world. This paper will design and study the light weight of the large and small sprockets, and hope to draw lessons from the design of the other university students’ equation racing car
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