20,451 research outputs found
Quantifying and Transferring Contextual Information in Object Detection
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The Fractional Quantum Hall States at and and their Non-Abelian Nature
We investigate the nature of the fractional quantum Hall (FQH) state at
filling factor , and its particle-hole conjugate state at ,
with the Coulomb interaction, and address the issue of possible competing
states. Based on a large-scale density-matrix renormalization group (DMRG)
calculation in spherical geometry, we present evidence that the physics of the
Coulomb ground state (GS) at and is captured by the
parafermion Read-Rezayi RR state, . We first establish that the
state at is an incompressible FQH state, with a GS protected by a
finite excitation gap, with the shift in accordance with the RR state. Then, by
performing a finite-size scaling analysis of the GS energies for
with different shifts, we find that the state has the lowest
energy among different competing states in the thermodynamic limit. We find the
fingerprint of topological order in the FQH and
states, based on their entanglement spectrum and topological entanglement
entropy, both of which strongly support their identification with the
state. Furthermore, by considering the shift-free
infinite-cylinder geometry, we expose two topologically-distinct GS sectors,
one identity sector and a second one matching the non-Abelian sector of the
Fibonacci anyonic quasiparticle, which serves as additional evidence for the
state at and .Comment: 12 pages, 8 figure
Topological Characterization of Non-Abelian Moore-Read State using Density-Matrix Renormailzation Group
The non-Abelian topological order has attracted a lot of attention for its
fundamental importance and exciting prospect of topological quantum
computation. However, explicit demonstration or identification of the
non-Abelian states and the associated statistics in a microscopic model is very
challenging. Here, based on density-matrix renormalization group calculation,
we provide a complete characterization of the universal properties of bosonic
Moore-Read state on Haldane honeycomb lattice model at filling number
for larger systems, including both the edge spectrum and the bulk anyonic
quasiparticle (QP) statistics. We first demonstrate that there are three
degenerating ground states, for each of which there is a definite anyonic flux
threading through the cylinder. We identify the nontrivial countings for the
entanglement spectrum in accordance with the corresponding conformal field
theory. Through inserting the charge flux, it is found that two of the
ground states can be adiabatically connected through a fermionic
charge- QP being pumped from one edge to the other, while the
ground state in Ising anyon sector evolves back to itself. Furthermore, we
calculate the modular matrices and , which contain
all the information for the anyonic QPs. In particular, the extracted quantum
dimensions, fusion rule and topological spins from modular matrices positively
identify the emergence of non-Abelian statistics following the
Chern-Simons theory.Comment: 5 pages; 3 figure
A non-linear model of rubber shear springs validated by experiments
Vibrating flip-flow screens provide an effective solution for screening highly viscous or fine materials. However, yet, only linear theory has been applied to their design. Yet, to understand deficiencies and to improve performance an accurate model especially of the rubber shear springs equipped in screen frames is critical for its dynamics to predict e.g. frequency- and amplitude-dependent behaviour. In this paper, the amplitude dependency of the rubber shear spring is represented by employing a friction model in which parameters are fitted to an affine function rather constant values used for the classic Berg’s model; the fractional derivative model is used to describe its frequency dependency and compared to conventional dashpot and Maxwell models with its elasticity being represented by a nonlinear spring. The experimentally validated results indicate that the proposed model with a nonlinear spring, friction and fractional derivative model is able to more accurately describe the dynamic characteristics of a rubber shear spring compared with other models
Re-identification by Relative Distance Comparison
Abstract—Matching people across nonoverlapping camera views at different locations and different times, known as person reidentification, is both a hard and important problem for associating behavior of people observed in a large distributed space over a prolonged period of time. Person reidentification is fundamentally challenging because of the large visual appearance changes caused by variations in view angle, lighting, background clutter, and occlusion. To address these challenges, most previous approaches aim to model and extract distinctive and reliable visual features. However, seeking an optimal and robust similarity measure that quantifies a wide range of features against realistic viewing conditions from a distance is still an open and unsolved problem for person reidentification. In this paper, we formulate person reidentification as a relative distance comparison (RDC) learning problem in order to learn the optimal similarity measure between a pair of person images. This approach avoids treating all features indiscriminately and does not assume the existence of some universally distinctive and reliable features. To that end, a novel relative distance comparison model is introduced. The model is formulated to maximize the likelihood of a pair of true matches having a relatively smaller distance than that of a wrong match pair in a soft discriminant manner. Moreover, in order to maintain the tractability of the model in large scale learning, we further develop an ensemble RDC model. Extensive experiments on three publicly available benchmarking datasets are carried out to demonstrate the clear superiority of the proposed RDC models over related popular person reidentification techniques. The results also show that the new RDC models are more robust against visual appearance changes and less susceptible to model overfitting compared to other related existing models. Index Terms—Person reidentification, feature quantification, feature selection, relative distance comparison Ç
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