98 research outputs found
Computational exploration of a viable route to Kitaev-quantum spin liquid phase in OsCl
In this computational study, we explore a viable route to access the
Kitaev-Quantum Spin Liquid (QSL) state in a so-called spin-orbit assisted Mott
insulator OsCl. QSL state is stabilized in a substantial part of the
Hubbard --Hund's space of the quantum phase diagram obtained by
combining second-order perturbation and pseudo-Fermion renormalization group
calculations. Considering monolayer of recently synthesized OsCl as a case
study, we show that for small /, only Kitaev interaction
appears, albeit of smaller magnitude. Depending upon the nature of magnetic
interactions, the phase diagram also hosts other magnetic phases as well in
different regions. Negligibly small farther neighbor interactions appears as a
distinct feature of monolayer OsCl. Insights from our study may be helpful
in designing experiments on pertinent Kitaev-QSL candidate materials
A STUDY ON THE REPRESENTATIVE POINT OF HORSE’S CENTER OF GRAVITY
The purpose of this study was to explore are there bony landmarks on the horse body’s surface matching the motion of center of gravity. The relationship between the bony landmarks and the center of gravity during actual race under Buchner and Kubo horse inertial models were analyzed. Results showed Buchner and Kubo models had high consistency on the kinematic parameters of the center of gravity. Comparing the relationship of the middle of mesoscapula and tail root with the center of gravity in displacement, velocity and the absolute difference, it was found that the middle of mesoscapula under Kubo model is a suitable represent point of the center of gravity among the characteristic points of two models in the motion of observed race horses
Emergence of bond-dependent highly anisotropic magnetic interactions in SrRhO: a theoretical study
The quantum spin liquid states as a natural ground state of the Kitaev model
has led to a quest for new materials candidates hosting Kitaev physics. Yet,
there are very few material candidates in this category. Using a combination of
and model Hamiltonian methods, we propose that Ruddlesden-Popper
compound SrRhO belongs to this category. With a tight-binding model and
exact diagonalization approach, we show that despite substantial trigonal-like
distortion, the electronic and magnetic properties of SrRhO can be well
described in terms of pseudo-spin = 1/2 states. Magnetic interactions among
pseudo-spins, estimated using the second-order perturbation method are highly
bond-dependent anisotropic in nature with two particularly noticeable features,
antiferromagnetic Kitaev and Dzyaloshinskii-Moriya interactions. The gaped
spin-wave spectra of SrRhO obtained with linear spin-wave theory is
consistent with the underlying magnetic frustration. Additional analysis of the
role of individual or a particular combination of magnetic interactions reveals
that the spin-wave spectra of SrRhO is a combined effect of the highly
anisotropic interactions and a relatively simpler minimal model may not be
plausible in the current case. The crucial insights about coupling between the
local structural features and magnetic properties of SrRhO obtained in
this study may be helpful for future studies belonging to this class
Local-Global Temporal Difference Learning for Satellite Video Super-Resolution
Optical-flow-based and kernel-based approaches have been widely explored for
temporal compensation in satellite video super-resolution (VSR). However, these
techniques involve high computational consumption and are prone to fail under
complex motions. In this paper, we proposed to exploit the well-defined
temporal difference for efficient and robust temporal compensation. To fully
utilize the temporal information within frames, we separately modeled the
short-term and long-term temporal discrepancy since they provide distinctive
complementary properties. Specifically, a short-term temporal difference module
is designed to extract local motion representations from residual maps between
adjacent frames, which provides more clues for accurate texture representation.
Meanwhile, the global dependency in the entire frame sequence is explored via
long-term difference learning. The differences between forward and backward
segments are incorporated and activated to modulate the temporal feature,
resulting in holistic global compensation. Besides, we further proposed a
difference compensation unit to enrich the interaction between the spatial
distribution of the target frame and compensated results, which helps maintain
spatial consistency while refining the features to avoid misalignment.
Extensive objective and subjective evaluation of five mainstream satellite
videos demonstrates that the proposed method performs favorably for satellite
VSR. Code will be available at \url{https://github.com/XY-boy/TDMVSR}Comment: Submitted to IEEE TCSV
TORE: Token Reduction for Efficient Human Mesh Recovery with Transformer
In this paper, we introduce a set of effective TOken REduction (TORE)
strategies for Transformer-based Human Mesh Recovery from monocular images.
Current SOTA performance is achieved by Transformer-based structures. However,
they suffer from high model complexity and computation cost caused by redundant
tokens. We propose token reduction strategies based on two important aspects,
i.e., the 3D geometry structure and 2D image feature, where we hierarchically
recover the mesh geometry with priors from body structure and conduct token
clustering to pass fewer but more discriminative image feature tokens to the
Transformer. As a result, our method vastly reduces the number of tokens
involved in high-complexity interactions in the Transformer, achieving
competitive accuracy of shape recovery at a significantly reduced computational
cost. We conduct extensive experiments across a wide range of benchmarks to
validate the proposed method and further demonstrate the generalizability of
our method on hand mesh recovery. Our code will be publicly available once the
paper is published
Cooling performance in a minichannel heat sink with different triangular pin-fins configurations
With the continuous progress of automotive new energy technology, the motor has become an important part of the power system, and the heat dissipation of insulated-gate bipolar transistors (IGBT) determines the reliability of the power system. Minichannel structure can be added to the thermal management system of new energy vehicles to improve the heat transfer capacity. Due to the growth of the boundary layer in the smooth minichannel flow channel, the cooling performance improvement was limited. Pin-fins and rib structures were used to break the boundary layer and increased the heat transfer area to enhance the heat transfer capacity. In this study, a numerical simulation model of minichannel with triangular pin-fins with different rotation angles was established and calculated using the SST k-omega method. The temperature field, velocity field, pressure, and vortex distribution under different configurations were discussed in detail. The jet area formed by the prism wall and the side wall of the minichannel would impact the wall and reduce the growth of the boundary layer. However, the stagnation area generated in the center and corner will reduce the improvement of heat transfer capacity. The thermo-hydraulic characteristics of different configurations at different Reynolds numbers (Re), such as Nusselt number (Nu), Darcy friction resistance coefficient (f), and performance evaluation criterion (PEC), were analyzed. As Re increased, the best and worst configurations changed, the best configuration changed from the 90°–120° structure to the 120°–120° structure, and the worst configuration changed from the 75°–60° to the 60°–60° structure. When the Re = 663, the influence of the front and rear rotation angle on the cooling performance was explored. When the rotation angle was closer to 60°, the cooling performance of the minichannel was better. And the closer the rotation angle was to 120°, the cooling performance was better. This has a reference effect on the design of minichannel heat sinks
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