85,507 research outputs found
Well-posedness and global existence of 2D viscous shallow water system in Besov spaces
In this paper we consider the Cauchy problem for 2D viscous shallow water
system in Besov spaces. We firstly prove the local well-posedness of this
problem in , , by using the Littlewood-Paley theory, the Bony decomposition and the
theories of transport equations and transport diffusion equations. Then we can
prove the global existence of the system with small enough initial data in
, , and
. Our obtained results generalize and cover the recent results
in \cite{W}
Remarks on the Chern classes of Calabi-Yau moduli
We prove that the first Chern form of the moduli space of polarized
Calabi-Yau manifolds, with the Hodge metric or the Weil-Petersson metric,
represent the first Chern class of the canonical extensions of the tangent
bundle to the compactification of the moduli space with normal crossing
divisors.Comment: 14 pages, no figure
DeepSSM: Deep State-Space Model for 3D Human Motion Prediction
Predicting future human motion plays a significant role in human-machine
interactions for a variety of real-life applications. In this paper, we build a
deep state-space model, DeepSSM, to predict future human motion. Specifically,
we formulate the human motion system as the state-space model of a dynamic
system and model the motion system by the state-space theory, offering a
unified formulation for diverse human motion systems. Moreover, a novel deep
network is designed to build this system, enabling us to utilize both the
advantages of deep network and state-space model. The deep network jointly
models the process of both the state-state transition and the state-observation
transition of the human motion system, and multiple future poses can be
generated via the state-observation transition of the model recursively. To
improve the modeling ability of the system, a unique loss function, ATPL
(Attention Temporal Prediction Loss), is introduced to optimize the model,
encouraging the system to achieve more accurate predictions by paying
increasing attention to the early time-steps. The experiments on two benchmark
datasets (i.e., Human3.6M and 3DPW) confirm that our method achieves
state-of-the-art performance with improved effectiveness. The code will be
available if the paper is accepted
Global existence for the two-component Camassa-Holm system and the modified two-component Camassa-Holm system
The present work is mainly concerned with global existence for the
two-component Camassa-Holm system and the modified two-component Camassa-Holm
system. By discovering new conservative quantities of these systems, we prove
several new global existence results for these two-component shallow water
systems.Comment: This paper has been withdrawn by the author due to a crucial erro
On the Cauchy problem of a two-component b-family equation
In this paper, we study the Cauchy problem of a two-component b-family
equation. We first establish the local well-posedness for a two-component
b-family equation by Kato's semigroup theory. Then, we derive precise blow-up
scenarios for strong solutions to the equation. Moreover, we present several
blow-up results for strong solutions to the equation
An Envelope for Davis-Yin Splitting and Strict Saddle Point Avoidance
It is known that operator splitting methods based on Forward Backward
Splitting (FBS), Douglas-Rachford Splitting (DRS), and Davis-Yin Splitting
(DYS) decompose a difficult optimization problems into simpler subproblems
under proper convexity and smoothness assumptions. In this paper, we identify
an envelope (an objective function) whose gradient descent iteration under a
variable metric coincides with DYS iteration. This result generalizes the
Moreau envelope for proximal-point iteration and the envelopes for FBS and DRS
iterations identified by Patrinos, Stella, and Themelis.
Based on the new envelope and the Stable-Center Manifold Theorem, we further
show that, when FBS or DRS iterations start from random points, they avoid all
strict saddle points with probability one. This results extends the similar
results by Lee et al. from gradient descent to splitting methods
Global weak solutions to a weakly dissipative HS equation
This paper is concerned with global existence of weak solutions for a weakly
dissipative HS equation by using smooth approximate to initial data and
Hellys theorem
On the Cauchy problem of a weakly dissipative HS equation
In this paper, we study the Cauchy problem of a weakly dissipative HS
equation. We first establish the local well-posedness for the weakly
dissipative HS equation by Kato's semigroup theory. Then, we derive the
precise blow-up scenario for strong solutions to the equation. Moreover, we
present some blow-up results for strong solutions to the equation. Finally, we
give two global existence results to the equation
Quantum Correction and the Moduli Spaces of Calabi-Yau Manifolds
We define the quantum correction of the Teichm\"uller space of
Calabi-Yau manifolds. Under the assumption of no weak quantum correction, we
prove that the Teichm\"uller space is a locally symmetric space
with the Weil-Petersson metric. For Calabi-Yau threefolds, we show that no
strong quantum correction is equivalent to that, with the Hodge metric, the
image of the Teichm\"uller space under the
period map is an open submanifold of a globally Hermitian symmetric
space of the same dimension as . Finally, for Hyperk\"ahler
manifold of dimension , we find both locally and globally defined
families of and -classes over the Teichm\"uller space of
polarized Hyperk\"ahler manifolds.Comment: 36 page
CPM-sensitive AUC for CTR prediction
The prediction of click-through rate (CTR) is crucial for industrial
applications, such as online advertising. AUC is a commonly used evaluation
indicator for CTR models. For advertising platforms, online performance is
generally evaluated by CPM. However, in practice, AUC often improves in offline
evaluation, but online CPM does not. As a result, a huge waste of precious
online traffic and human costs has been caused. This is because there is a gap
between offline AUC and online CPM. AUC can only reflect the order on CTR, but
it does not reflect the order of CTR*Bid. Moreover, the bids of different
advertisements are different, so the loss of income caused by different
reverse-order pair is also different. For this reason, we propose the
CPM-sensitive AUC (csAUC) to solve all these problems. We also give the csAUC
calculation method based on dynamic programming. It can fully support the
calculation of csAUC on large-scale data in real-world applications
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