854 research outputs found
New bounds on the Lieb-Thirring constants
Improved estimates on the constants , for ,
in the inequalities for the eigenvalue moments of Schr\"{o}dinger
operators are established
Finite lifetime eigenfunctions of coupled systems of harmonic oscillators
We find a Hermite-type basis for which the eigenvalue problem associated to
the operator acting on becomes a three-terms recurrence. Here and are two constant
positive definite matrices with no other restriction. Our main result provides
an explicit characterization of the eigenvectors of that lie in the
span of the first four elements of this basis when .Comment: 11 pages, 1 figure. Some typos where corrected in this new versio
Many Particle Hardy-Inequalities
In this paper we prove three differenttypes of the so-called many-particle
Hardy inequalities. One of them is a "classical type" which is valid in any
dimesnion . The second type deals with two-dimensional magnetic
Dirichlet forms where every particle is supplied with a soplenoid. Finally we
show that Hardy inequalities for Fermions hold true in all dimensions.Comment: 20 page
Much Ado About Time: Exhaustive Annotation of Temporal Data
Large-scale annotated datasets allow AI systems to learn from and build upon
the knowledge of the crowd. Many crowdsourcing techniques have been developed
for collecting image annotations. These techniques often implicitly rely on the
fact that a new input image takes a negligible amount of time to perceive. In
contrast, we investigate and determine the most cost-effective way of obtaining
high-quality multi-label annotations for temporal data such as videos. Watching
even a short 30-second video clip requires a significant time investment from a
crowd worker; thus, requesting multiple annotations following a single viewing
is an important cost-saving strategy. But how many questions should we ask per
video? We conclude that the optimal strategy is to ask as many questions as
possible in a HIT (up to 52 binary questions after watching a 30-second video
clip in our experiments). We demonstrate that while workers may not correctly
answer all questions, the cost-benefit analysis nevertheless favors consensus
from multiple such cheap-yet-imperfect iterations over more complex
alternatives. When compared with a one-question-per-video baseline, our method
is able to achieve a 10% improvement in recall 76.7% ours versus 66.7%
baseline) at comparable precision (83.8% ours versus 83.0% baseline) in about
half the annotation time (3.8 minutes ours compared to 7.1 minutes baseline).
We demonstrate the effectiveness of our method by collecting multi-label
annotations of 157 human activities on 1,815 videos.Comment: HCOMP 2016 Camera Read
Stability of the magnetic Schr\"odinger operator in a waveguide
The spectrum of the Schr\"odinger operator in a quantum waveguide is known to
be unstable in two and three dimensions. Any enlargement of the waveguide
produces eigenvalues beneath the continuous spectrum. Also if the waveguide is
bent eigenvalues will arise below the continuous spectrum. In this paper a
magnetic field is added into the system. The spectrum of the magnetic
Schr\"odinger operator is proved to be stable under small local deformations
and also under small bending of the waveguide. The proof includes a magnetic
Hardy-type inequality in the waveguide, which is interesting in its own
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