1,495 research outputs found
Generalized Gravitational Entropy from Total Derivative Action
We investigate the generalized gravitational entropy from total derivative
terms in the gravitational action. Following the method of Lewkowycz and
Maldacena, we find that the generalized gravitational entropy from total
derivatives vanishes. We compare our results with the work of Astaneh,
Patrushev, and Solodukhin. We find that if total derivatives produced nonzero
entropy, the holographic and the field-theoretic universal terms of
entanglement entropy would not match. Furthermore, the second law of
thermodynamics could be violated if the entropy of total derivatives did not
vanish.Comment: 24 pages; v2: added references, Sec. 5.2 for corner entanglement, a
toy model in Sec. 5.3, and minor corrections; v3: added one reference,
published versio
Effect Equilibrium Approach in Calculating the Economic Range of a Freeway Industrial Zone
This research aims to develop a valid method to examine the relationship between transportation infrastructure and economic growth through the measurement of the economic boundary of a freeway industrial zone in developing countries. By comparing the similarities of a freeway industrial zone with an electromagnetic field, the Boit-Schwander law in electromagnetism is applied to create an electromagnetic model, which can calculate the attractive effect caused by a freeway on its influential area. When the attractive effect is equal to the traffic impedance, the economic range of the industrial zone can be determined by the effective equilibrium approach. An empirical analysis of the Ha-Shuang freeway demonstrates this approach is valid and practical
Bilinear Kakeya-Nikodym averages of eigenfunctions on compact Riemannian surfaces
We obtain an improvement of the bilinear estimates of Burq, G\'erard and
Tzvetkov in the spirit of the refined Kakeya-Nikodym estimates of Blair and the
second author. We do this by using microlocal techniques and a bilinear version
of H\"ormander's oscillatory integral theorem.Comment: 19 pages, 1 figure. Affiliation correcte
EFormer: Enhanced Transformer towards Semantic-Contour Features of Foreground for Portraits Matting
The portrait matting task aims to extract an alpha matte with complete
semantics and finely-detailed contours. In comparison to CNN-based approaches,
transformers with self-attention allow a larger receptive field, enabling it to
better capture long-range dependencies and low-frequency semantic information
of a portrait. However, the recent research shows that self-attention mechanism
struggle with modeling high-frequency information and capturing fine contour
details, which can lead to bias while predicting the portrait's contours. To
address the problem, we propose EFormer to enhance the model's attention
towards semantic and contour features. Especially the latter, which is
surrounded by a large amount of high-frequency details. We build a semantic and
contour detector (SCD) to accurately capture the distribution of semantic and
contour features. And we further design contour-edge extraction branch and
semantic extraction branch for refining contour features and complete semantic
information. Finally, we fuse the two kinds of features and leverage the
segmentation head to generate the predicted portrait matte. Remarkably, EFormer
is an end-to-end trimap-free method and boasts a simple structure. Experiments
conducted on VideoMatte240K-JPEGSD and AIM datasets demonstrate that EFormer
outperforms previous portrait matte methods.Comment: 17 pages, 6 figure
Inductive Data Types Based on Fibrations Theory in Programming
Traditional methods including algebra and category theory have some deficiencies in analyzing semantics properties and describing inductive rules of inductive data types, we present a method based on Fibrations theory aiming at those questions above. We systematically analyze some basic logical structures of inductive data types about a fibration such as re-indexing functor, truth functor and comprehension functor, make semantics models of non-indexed fibration, single-sorted indexed fibration and many-sorted indexed fibration respectively. On this basis, we thoroughly discuss semantics properties of fibred, single-sorted indexed and many-sorted indexed inductive data types, and abstractly describe their inductive rules with universality. Furthermore, we briefly introduce applications of the three inductive dana types for analyzing semantics properties and describing inductive rules based on Fibrations theory via some examples. Compared with traditional methods, our works have the following three advantages. Firstly, brief descriptions and flexible expansibility of Fibrations theory can analyze semantics properties of inductive data types accurately, whose semantics are computed automatically. Secondly, superior abstractness of Fibrations theory does not rely on particular computing environments to depict inductive rules of inductive data types with universality. Thirdly, its rigorousness and consistence provide sound basis for testing and maintenance of software development
Agile forecasting of dynamic logistics demand
The objective of this paper is to study the quantitative forecasting method for agile forecasting of logistics demand in dynamic supply chain environment. Characteristics of dynamic logistics demand and relative forecasting methods are analyzed. In order to enhance the forecasting efficiency and precision, extended Kalman Filter is applied to training artificial neural network, which serves as the agile forecasting algorithm. Some dynamic influencing factors are taken into consideration and further quantified in agile forecasting. Swarm simulation is used to demonstrate the forecasting results. Comparison analysis shows that the forecasting method has better reliability for agile forecasting of dynamic logistics demand.
First published online: 27 Oct 201
Improved local smoothing estimate for the wave equation in higher dimensions
In this paper, we establish the sharp -broad estimate for a class of phase
functions satisfying the homogeneous convex conditions. As an application, we
obtain improved local smoothing estimates for the half-wave operator in
dimensions . As a byproduct, we also generalize the restriction
estimates of Ou--Wang to a broader class of phase functions.Comment: 32 pages, 3 figures, Referees' suggestions incorporated. To appear in
J. Func. Ana
6-Chloro-2-phenyl-3-(2-phenylethynyl)quinoxaline
In the title compound, C22H13ClN2, the quinoxaline ring system is close to planar [maximum deviation = 0.061 (2) Å]. The phenyl ring at the 2-position and the phenyl ring of the phenylethynyl substituent make dihedral angles of 49.32 (7) and 11.99 (7) °, respectively, with the quinoxaline mean plane. The two phenyl rings are inclined to one another by 61.27 (9)°. In the crystal, molecules are linked by C—H⋯π and π–π interactions [centroid–centroid distances = 3.6210 (12) and 3.8091 (12) Å]
Truncated atomic plane wave method for the subband structure calculations of Moir\'e systems
We propose a highly efficient and accurate numerical scheme named Truncated
Atomic Plane Wave (TAPW) method to determine the subband structure of Twisted
Bilayer Graphene (TBG) inspired by BM model. Our method utilizes real space
information of carbon atoms in the moir\'e unit cell and projects the full
tight binding Hamiltonian into a much smaller subspace using atomic plane
waves. We present accurate electronic band structures of TBG in a wide range of
twist angles together with detailed moir\'e potential and screened Coulomb
interaction at the first magic angle using our new method. Furthermore, we
generalize our formalism to solve the problem of low frequency moir\'e phonons
in TBG
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