4,315 research outputs found
Alternating minimization algorithms for graph regularized tensor completion
We consider a low-rank tensor completion (LRTC) problem which aims to recover
a tensor from incomplete observations. LRTC plays an important role in many
applications such as signal processing, computer vision, machine learning, and
neuroscience. A widely used approach is to combine the tensor completion data
fitting term with a regularizer based on a convex relaxation of the multilinear
ranks of the tensor. For the data fitting function, we model the tensor
variable by using the Canonical Polyadic (CP) decomposition and for the
low-rank promoting regularization function, we consider a graph Laplacian-based
function which exploits correlations between the rows of the matrix unfoldings.
For solving our LRTC model, we propose an efficient alternating minimization
algorithm. Furthermore, based on the Kurdyka-{\L}ojasiewicz property, we show
that the sequence generated by the proposed algorithm globally converges to a
critical point of the objective function. Besides, an alternating direction
method of multipliers algorithm is also developed for the LRTC model. Extensive
numerical experiments on synthetic and real data indicate that the proposed
algorithms are effective and efficient
RNA sequencing analysis to capture the transcriptome landscape during skin ulceration syndrome progression in sea cucumber Apostichopus japonicus
Complement and coagulation cascades pathways (tif). Red boxes represent up-regulated genes, and green boxes represent down-regulated genes. (TIF 627 kb
Recurrent deletions of ULK4 in schizophrenia : a gene crucial for neuritogenesis and neuronal motility
Peer reviewedPublisher PD
Observation of Majorana fermions with spin selective Andreev reflection in the vortex of topological superconductor
Majorana fermion (MF) whose antiparticle is itself has been predicted in
condensed matter systems. Signatures of the MFs have been reported as zero
energy modes in various systems. More definitive evidences are highly desired
to verify the existence of the MF. Very recently, theory has predicted MFs to
induce spin selective Andreev reflection (SSAR), a novel magnetic property
which can be used to detect the MFs. Here we report the first observation of
the SSAR from MFs inside vortices in Bi2Te3/NbSe2 hetero-structure, in which
topological superconductivity was previously established. By using
spin-polarized scanning tunneling microscopy/spectroscopy (STM/STS), we show
that the zero-bias peak of the tunneling differential conductance at the vortex
center is substantially higher when the tip polarization and the external
magnetic field are parallel than anti-parallel to each other. Such strong spin
dependence of the tunneling is absent away from the vortex center, or in a
conventional superconductor. The observed spin dependent tunneling effect is a
direct evidence for the SSAR from MFs, fully consistent with theoretical
analyses. Our work provides definitive evidences of MFs and will stimulate the
MFs research on their novel physical properties, hence a step towards their
statistics and application in quantum computing.Comment: 4 figures 15 page
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