Results for "Kai-Xing Lu"

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High-order Phase Transition in Random HypergrpahsSep 03 2014In this paper, we study the high-order phase transition in random $r$-uniform hypergraphs. For a positive integer $n$ and a real $p\in [0,1]$, let $H:=H^r(n,p)$ be the random $r$-uniform hypergraph on the vertex set $[n]$, where each $r$-set is an edge ... More
High-ordered Random Walks and Generalized Laplacians on HypergraphsFeb 22 2011Despite of the extreme success of the spectral graph theory, there are relatively few papers applying spectral analysis to hypergraphs. Chung first introduced Laplacians for regular hypergraphs and showed some useful applications. Other researchers treated ... More
Spectra of edge-independent random graphsApr 27 2012Let $G$ be a random graph on the vertex set $\{1,2,..., n\}$ such that edges in $G$ are determined by independent random indicator variables, while the probability $p_{ij}$ for $\{i,j\}$ being an edge in $G$ is not assumed to be equal. Spectra of the ... More
Loose Laplacian spectra of random hypergraphsSep 15 2011Dec 05 2011Let $H=(V,E)$ be an $r$-uniform hypergraph with the vertex set $V$ and the edge set $E$. For $1\leq s \leq r/2$, we define a weighted graph $G^{(s)}$ on the vertex set ${V\choose s}$ as follows. Every pair of $s$-sets $I$ and $J$ is associated with a ... More
High-order Phase Transition in Random HypergrpahsSep 03 2014Aug 02 2018In this paper, we study the high-order phase transition in random $r$-uniform hypergraphs. For a positive integer $n$ and a real $p\in [0,1]$, let $H:=H^r(n,p)$ be the random $r$-uniform hypergraph with vertex set $[n]$, where each $r$-set is selected ... More
Monochromatic 4-term arithmetic progressions in 2-colorings of $\mathbb Z_n$Jul 14 2011This paper is motivated by a recent result of Wolf \cite{wolf} on the minimum number of monochromatic 4-term arithmetic progressions(4-APs, for short) in $\Z_p$, where $p$ is a prime number. Wolf proved that there is a 2-coloring of $\Z_p$ with 0.000386% ... More
The Fractional Chromatic Number of Triangle-free Graphs with $Δ\leq 3$Nov 10 2010Jul 25 2012Let $G$ be any triangle-free graph with maximum degree $\Delta\leq 3$. Staton proved that the independence number of $G$ is at least 5/14n. Heckman and Thomas conjectured that Staton's result can be strengthened into a bound on the fractional chromatic ... More
Butterfly Velocity Bound and Reverse Isoperimetric InequalityJan 18 2017Jan 24 2017We study the butterfly effect of the AdS planar black holes in the framework of Einstein's general relativity. We find that the butterfly velocities can be expressed by a universal formula $v_{\rm B}^2 = TS/(2V_{\rm th} P)$. In doing so, we come upon ... More
Higher-Derivative Gravity with Non-minimally Coupled Maxwell FieldDec 30 2015We construct higher-derivative gravities with a non-minimally coupled Maxwell field. The Lagrangian consists of polynomial invariants built from the Riemann tensor and the Maxwell field strength in such a way that the equations of motion are second order ... More
Solutions of Free Higher Spins in AdSOct 06 2011Oct 18 2011We consider free massive and massless higher integer spins in AdS backgrounds in general D dimensions. We obtain the solutions corresponding to the highest-weight state of the spin-\ell representations of the SO(2,D-1) isometry groups. The solution for ... More
The super-super exchange mechanism in iron-based antiperovskite chalco-halidesApr 07 2016By using the first-principles electronic structure calculations, we have systematically studied the magnetism in three recently synthesized iron-based antiperovskite chalco-halides: Ba$_3$(FeS$_4$)Cl, Ba$_3$(FeS$_4$)Br, and Ba$_3$(FeSe$_4$)Br. These compounds ... More
Reverberation mapping of narrow-line Seyfert 1 galaxy I Zwicky 1: black hole massApr 12 2019We report results of the first reverberation mapping campaign of I Zwicky 1 during $2014$-$2016$, which showed unambiguous reverberations of the broad H$\beta$ line emission to the varying optical continuum. From analysis using several methods, we obtain ... More
Spectroscopic Indication for a Centi-parsec Supermassive Black Hole Binary in the Galactic Center of NGC 5548Feb 16 2016Mar 04 2016As a natural consequence of cosmological hierarchical structure formation, sub-parsec supermassive black hole binaries (SMBHBs) should be common in galaxies but thus far have eluded spectroscopic identification. Based on four decades of optical spectroscopic ... More
Scalar Hairy Black Holes in General DimensionsDec 18 2013Jan 13 2014We obtain a class of asymptotic flat or (A)dS hairy black holes in D-dimensional Einstein gravity coupled to a scalar with certain scalar potential. For a given mass, the theory admits both the Schwarzschild-Tangherlini and the hairy black holes with ... More
Equivalent classes in matching covered graphsFeb 25 2019Let $G$ be a matching covered graph. Two edges $ e_1$ and $e_2$ of $G$ are {\it equivalent} if $\{e_1,e_2\}\subseteq M$ or $\{e_1,e_2\}\cap M=\emptyset$ for every perfect matching $M$ of $G$. An {\it equivalent class} of $G$ is an edge set $S$ of $G$ ... More
Holographic Complexity and Two Identities of Action GrowthNov 07 2016Nov 23 2016The recently proposed complexity-action conjecture allows one to calculate how fast one can produce a quantum state from a reference state in terms of the on-shell action of the dual AdS black hole at the Wheeler-DeWitt patch. We show that the action ... More
A Fractional Analogue of Brooks' TheoremMar 17 2011Nov 13 2011Let $\Delta(G)$ be the maximum degree of a graph $G$. Brooks' theorem states that the only connected graphs with chromatic number $\chi(G)=\Delta(G)+1$ are complete graphs and odd cycles. We prove a fractional analogue of Brooks' theorem in this paper. ... More
$b$-invariant edges in cubic near-bipartite bricksMay 17 2019May 20 2019A brick is a non-bipartite graph without non-trivial tight cuts. Bricks are building blocks of matching covered graphs. We say that an edge $e$ in a brick $G$ is $b$-invariant if $G-e$ is matching covered and it contains exactly one brick. Kothari, Carvalho, ... More
Cooperative Multi-Agent Policy Gradients with Sub-optimal DemonstrationDec 05 2018Many reality tasks such as robot coordination can be naturally modelled as multi-agent cooperative system where the rewards are sparse. This paper focuses on learning decentralized policies for such tasks using sub-optimal demonstration. To learn the ... More
Charged Plate in Asymmetric Electrolytes: One-loop Renormalization of Surface Charge Density and Debye Length due to Ionic CorrelationsFeb 12 2016The self-consistent field theory (SCFT) is used to study the mean potential near a charged plate inside a $m:-n$ electrolyte. A perturbation series is developed in terms of $g = 4 \pi b/\ell_{\rm {\scriptscriptstyle DB}}$, where $b, \ell_{\rm{\scriptscriptstyle ... More
Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. VIII. Structure of the Broad-Line Region and Mass of the Central Black Hole in Mrk 142Nov 15 2018This is the eighth in a series of papers reporting on a large reverberation mapping campaign to measure black hole (BH) mass in high accretion rate active galactic nuclei (AGNs). We employ the recently developed dynamical modeling approach for broad-line ... More
Optical and Gamma-Ray Variability Behaviors of 3C 454.3 from 2006 to 2011Feb 15 2018We present our photometric monitoring of a flat spectrum radio quasar (FSRQ) 3C 454.3 at Yunnan observatories from 2006 to 2011. We find that the optical color of 3C 454.3 shows obvious redder-when-brighter trend, which reaches a saturation stage when ... More
Frequency domain TRINICON-based blind source separation method with multi-source activity detection for sparsely mixed signalsFeb 25 2018The TRINICON ('Triple-N ICA for convolutive mixtures') framework is an effective blind signal separation (BSS) method for separating sound sources from convolutive mixtures. It makes full use of the non-whiteness, non-stationarity and non-Gaussianity ... More
Discrete-Time Output-Feedback Robust Repetitive Control for a Class of Nonlinear Systems by Additive State DecompositionJan 08 2014The discrete-time robust repetitive control (RC, or repetitive controller, also designated RC) problem for nonlinear systems is both challenging and practical. This paper proposes a discrete-time output-feedback RC design for a class of systems subject ... More
Novel Fermi Liquid of 2D Polar MoleculesNov 30 2011We study Fermi liquid properties of a weakly interacting 2D gas of single-component fermionic polar molecules with dipole moments $d$ oriented perpendicularly to the plane of their translational motion. This geometry allows the minimization of inelastic ... More
Hyper-parameter Tuning under a Budget ConstraintFeb 01 2019We study a budgeted hyper-parameter tuning problem, where we optimize the tuning result under a hard resource constraint. We propose to solve it as a sequential decision making problem, such that we can use the partial training progress of configurations ... More
Fast 3D Line Segment Detection From Unorganized Point CloudJan 08 2019This paper presents a very simple but efficient algorithm for 3D line segment detection from large scale unorganized point cloud. Unlike traditional methods which usually extract 3D edge points first and then link them to fit for 3D line segments, we ... More
RLS-Based Adaptive Dereverberation Tracing Abrupt Position Change of Target SpeakerFeb 25 2018Aug 23 2018Adaptive algorithm based on multi-channel linear prediction is an effective dereverberation method balancing well between the attenuation of the long-term reverberation and the dereverberated speech quality. However, the abrupt change of the speech source ... More
Electronic structures of quasi-one-dimensional cuprate superconductors Ba$_2$CuO$_{3+δ}$Jan 31 2019An intact CuO$_2$ plane is widely believed to be a prerequisite for the high-$T_c$ superconductivity in cuprate superconductors. However, an exception may exist in the superconducting Ba$_2$CuO$_{3+\delta}$ materials where CuO chains play a more important ... More
Decoupled Heterogeneous Networks with Millimeter Wave Small CellsNov 02 2017Deploying sub-6GHz network together with millimeter wave (mmWave) is a promising solution to simultaneously achieve sufficient coverage and high data rate. In the heterogeneous networks (HetNets), the traditional coupled access, i.e., the users are constrained ... More
Nematic antiferromagnetic states in bulk FeSeOct 26 2015We revisit bulk FeSe through the systematic first-principles electronic structure calculations. We find that there are a series of staggered $n$-mer antiferromagnetic (AFM) states with corresponding energies below that of the collinear AFM state which ... More
Atomic and electronic structures of FeSe monolayer and bilayer thin films on SrTiO$_3$ (001): a first-principles studyFeb 02 2012Feb 06 2012By the first-principles electronic structure calculations, we have studied electronic structures of FeSe monolayer and bilayer thin films on SrTiO$_3$ (001) with SrO-termination or TiO$_2$ termination. We find that both FeSe monolayer and bilayer on either ... More
Optimizing DF Cognitive Radio Networks with Full-Duplex-Enabled Energy Access PointsNov 16 2016Mar 28 2017With the recent advances in radio frequency (RF) energy harvesting (EH) technologies, wireless powered cooperative cognitive radio network (CCRN) has drawn an upsurge of interest for improving the spectrum utilization with incentive to motivate joint ... More
Wireless Powered Cooperative Jamming for Secrecy Multi-AF Relaying NetworksNov 11 2015This paper studies secrecy transmission with the aid of a group of wireless energy harvesting (WEH)-enabled amplify-and-forward (AF) relays performing cooperative jamming (CJ) and relaying. The source node in the network does simultaneous wireless information ... More
YouSense: Mitigating Entropy Selfishness in Distributed Collaborative Spectrum SensingNov 22 2011Mar 21 2013Collaborative spectrum sensing has been recognized as a promising approach to improve the sensing performance via exploiting the spatial diversity of the secondary users. In this study, a new selfishness issue is identified, that selfish users sense no ... More
Robust topological edge states at the perfect surface step edge of topological insulator ZrTe$_5$Jan 22 2016We report an atomic-scale characterization of ZrTe$_5$ by using scanning tunneling microscopy. We observe a bulk bandgap of ~80 meV with topological edge states at the step edge, and thus demonstrate ZrTe$_5$ is a two dimensional topological insulator. ... More
Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. V. A New Size-Luminosity Scaling Relation for the Broad-Line RegionApr 21 2016This paper reports results of the third-year campaign of monitoring super-Eddington accreting massive black holes (SEAMBHs) in active galactic nuclei (AGNs) between 2014-2015. Ten new targets were selected from quasar sample of Sloan Digital Sky Survey ... More
Bounce Universe and Black Holes from Critical Einsteinian Cubic GravityJul 19 2017We show that there exists a critical point for the coupling constants in Einsteinian cubic gravity where the linearized equations on the maximally-symmetric vacuum vanish identically. We construct an exact isotropic bounce universe in the critical theory ... More
Efficient Graph Edit Distance Computation and Verification via Anchor-aware Lower Bound EstimationSep 20 2017Oct 01 2017Graph edit distance (GED) is an important similarity measure adopted in a similarity-based analysis between two graphs, and computing GED is a primitive operator in graph database analysis. Partially due to the NP-hardness, the existing techniques for ... More
Time Machines and AdS Solitons with Negative MassDec 30 2016We show that in D=2n+1 dimensions, when mass is negative and all angular momenta are non-vanishing, Kerr and Kerr-AdS metrics describe smooth time machines, with no curvature singularity. Turning off the angular momenta appropriately can lead to static ... More
Distributed interaction between computer virus and patch: A modeling studyMay 13 2017The decentralized patch distribution mechanism holds significant promise as an alternative to its centralized counterpart. For the purpose of accurately evaluating the performance of the decentralized patch distribution mechanism and based on the exact ... More
High temperature superconducting phase of HBr under pressure predicted by first-principles calculationsAug 14 2017The high pressure phases of HBr are explored with an ab initio crystal structure search. By taking into account the contribution of zero-point energy (ZPE), we find that the P4/nmm phase of HBr is thermodynamically stable in the pressure range from 150 ... More
Topological thermal Hall effect driven by fluctuation of spin chirality in frustrated antiferromagnetsNov 18 2018Nov 22 2018By revealing an underlying relation between the Dzyaloshinskii-Moriya interaction (DMI) and the scalar spin chirality, we develop the theory of magnon thermal Hall effects in antiferromagnetic systems. The dynamic fluctuation of the scalar chirality is ... More
Anisotropic deformation of Rydberg blockade sphere in few-atom systemsSep 02 2013Rydberg blockade sphere persists an intriguing picture by which a number of collective many-body effects caused by the strong Rydberg-Rydberg interactions can be clearly understood and profoundly investigated. In the present work, we develop a new definition ... More
Multifractal characteristics and return predictability in the Chinese stock marketsJun 20 2018By adopting Multifractal detrended fluctuation (MF-DFA) analysis methods, the multifractal nature is revealed in the high-frequency data of two typical indexes, the Shanghai Stock Exchange Composite 180 Index (SH180) and the Shenzhen Stock Exchange Composite ... More
Godel Universe from String TheoryDec 06 2016Dec 12 2016G\"odel universe is a direct product of a line and a three-dimensional spacetime we call G$_\alpha$. In this paper, we show that the G\"odel metrics can arise as exact solutions in Einstein-Maxwell-Axion, Einstein-Proca-Axion, or Freedman-Schwarz gauged ... More
Multiscale Technicolor and the Zbb-bar VertexSep 28 1995We estimate the correction to the Zbb-bar vertex arising from the exchanges of the sideways extended technicolor (ETC) boson and the flavor-diagonal ETC boson in the multiscale walking technicolor model. The obtained result is too large to explain the ... More
Improving Deep Pancreas Segmentation in CT and MRI Images via Recurrent Neural Contextual Learning and Direct Loss FunctionJul 16 2017Jul 18 2017Deep neural networks have demonstrated very promising performance on accurate segmentation of challenging organs (e.g., pancreas) in abdominal CT and MRI scans. The current deep learning approaches conduct pancreas segmentation by processing sequences ... More
The Integrated Sachs-Wolfe Effect in Time Varying Vacuum ModelApr 20 2010The integrated Sachs-Wolfe (ISW) effect is an important implication for dark energy. In this paper, we have calculated the power spectrum of the ISW effect in the time varying vacuum cosmological model, where the model parameter $\beta=4.407$ is obtained ... More
A Novel Rate and Channel Control Scheme Based on Data Extraction Rate for LoRa NetworksFeb 12 2019Long Range (LoRa) has become one of the most popular Low Power Wide Area (LPWA) technologies, which provides a desirable trade-off among communication range, battery life, and deployment cost. In LoRa networks, several transmission parameters can be allocated ... More
Statistical physics of isotropic-genesis nematic elastomers: I. Structure and correlations at high temperaturesApr 14 2013Isotropic-genesis nematic elastomers (IGNEs) are liquid crystalline polymers (LCPs) that have been randomly, permanently cross-linked in the high-temperature state so as to form an equilibrium random solid. Thus, instead of being free to diffuse throughout ... More
Generalized Deam-Edwards Approach to the Statistical Mechanics of Randomly Crosslinked SystemsMay 03 2013We address the statistical mechanics of randomly and permanently crosslinked networks. We develop a theoretical framework (vulcanization theory) which can be used to systematically analyze the correlation between the statistical properties of random networks ... More
Fragmentation of Molecular Clumps and Formation of ProtoclusterMar 10 2015Sufficiently massive clumps of molecular gas collapse under self-gravity and fragment to spawn a cluster of stars that have a range of masses. We investigate observationally the early stages of formation of a stellar cluster in a massive filamentary infrared ... More
Rotating Solutions in Critical Lovelock GravitiesSep 28 2016For appropriate choices of the coupling constants, the equations of motion of Lovelock gravities up to order n in the Riemann tensor can be factorized such that the theories admits a single (A)dS vacuum. In this paper we construct two classes of exact ... More
Lijiang 2.4-meter Telescope and its InstrumentsMay 15 2019Lijiang 2.4-meter Telescope(LJT), the largest common-purpose optical telescope in China, has been applied to the world-wide astronomers since 2008. It is located at Gaomeigu site, Lijiang Observatory(LJO), the southwest of China. The site has very good ... More
A Unified Mechanism for Hydrogen Trapping at Metal VacanciesNov 05 2013Interaction between hydrogen (H) and metals is central to many materials problems of scientific and technological importance. Chief among them is the development of H storage and H-resistant materials. H segregation or trapping at lattice defects, including ... More
Efficient improvement of frequency-domain Kalman filterAug 25 2018The frequency-domain Kalman filter (FKF) has been utilized in many audio signal processing applications due to its fast convergence speed and robustness. However, the performance of the FKF in under-modeling situations has not been investigated. This ... More
Magnetic interactions in a proposed diluted magnetic semiconductor (Ba$_\text{1-x}$K$_\text{x}$)(Zn$_\text{1-y}$Mn$_\text{y}$)$_\text{2}$P$_\text{2}$Apr 12 2018By using first-principles electronic structure calculations, we have studied the magnetic interactions in a proposed BaZn$_2$P$_2$-based diluted magnetic semiconductor (DMS). For a typical compound Ba(Zn$_{0.944}$Mn$_{0.056}$)$_2$P$_2$ with only spin ... More
Difference in Narrow Emission Line Spectra of Seyfert 1 and 2 galaxiesAug 22 2008In the unification scheme of Seyfert galaxies, a dusty torus blocks the continuum source and broad line region in Seyfert 2 galaxies. However it is not clear whether or not and to what extent the torus affects the narrow line spectra. In this paper, we ... More
Exact Analysis of Scaling and Dominant Attractors Beyond the Exponential PotentialOct 23 2008Jun 20 2009By considering the potential parameter $\Gamma$ as a function of another potential parameter $\lambda$[47], We successfully extend the analysis of two-dimensional autonomous dynamical system of quintessence scalar field model to the analysis of three-dimension, ... More
The influence of spin-phonon coupling on antiferromagnetic spin fluctuations in FeSe under pressure: the First-principles calculations with van der Waals correctionsSep 10 2013The electronic structures, lattice dynamics, and magnetic properties of crystal {\beta}-FeSe under hydrostatic pressure have been studied by using the first-principles electronic structure calculations with van der Waals (vdW) corrections. With applied ... More
Tuning the magnetism of the top-layer FeAs on BaFe$_{2}$As$_{2}$(001): First-principles studyAug 01 2017The magnetic properties of BaFe$_{2}$As$_{2}$(001) surface have been studied by using first-principles electronic structure calculations. We find that for As-terminated surface the magnetic ground state of the top-layer FeAs is in the staggered dimer ... More
Laterally emitted surface second harmonic generation in a single ZnTe nanowireNov 15 2012Apr 16 2013We report a direct observation on the unique laterally emitted surface second harmonic generation (SHG) in a single ZnTe nanowire. The highly directional surface SHG signal that polarizes along the direction vertical to the nanowire growth axis, is significantly ... More
Merging the Bernoulli-Gaussian and Symmetric Alpha-Stable Models for Impulsive Noises in Narrowband Power Line ChannelsOct 25 2017Jan 08 2019To model impulsive noise in power line channels, both the Bernoulli-Gaussian model and the symmetric alpha-stable model are usually applied. Towards a merge of existing noise measurement databases and a simplification of communication system design, the ... More
Surface Plasmonic Lattice Solitons in Semi-infinite Graphene Sheet ArraysNov 21 2016We investigate the surface plasmonic lattice solitons (PLSs) in semi-infinite graphene sheet arrays. The surface soliton is formed as the SPPs tunneling is inhibited by the graphene nonlinearity, and meanwhile the incident power should be above a threshold ... More
Secure Reusable Base-String in Quantum Key DistributionJun 26 2007Protecting secure random key from eavesdropping in quantum key distribution protocols has been well developed. In this letter, we further study how to detect and eliminate eavesdropping on the random base string in such protocols. The correlation between ... More
Resonance of Gaussian electromagnetic field to the high frequency gravitational wavesNov 07 2014May 28 2016We consider a Gaussian Beam (GB) resonant system for high frequency gravitational waves (HFGWs) detection. At present, we find the optimal signal strength in theory through setting the magnetic component of GB in a standard gaussian form. Under the synchro-resonance ... More
Vertex Priority Based Butterfly Counting for Large-scale Bipartite NetworksDec 01 2018Apr 16 2019Bipartite networks are of great importance in many real-world applications. In bipartite networks, butterfly (i.e., a complete 2 x 2 biclique) is the smallest non-trivial cohesive structure and plays a key role. In this paper, we study the problem of ... More
One-Lee weight and two-Lee weight $\mathbb{Z}_2\mathbb{Z}_2[u]$-additive codesSep 30 2016Feb 02 2018In this paper, we study one-Lee weight and two-Lee weight codes over $\mathbb{Z}_{2}\mathbb{Z}_{2}[u]$, where $u^{2}=0$. Some properties of one-Lee weight $\mathbb{Z}_{2}\mathbb{Z}_{2}[u]$-additive codes are given, and a complete classification of one-Lee ... More
Zero sound in a two-dimensional dipolar Fermi gasJul 15 2013We study zero sound in a weakly interacting 2D gas of single-component fermionic dipoles (polar molecules or atoms with a large magnetic moment) tilted with respect to the plane of their translational motion. It is shown that the propagation of zero sound ... More
Convolutional Geometric Matrix CompletionMar 02 2018May 27 2019Geometric matrix completion (GMC) has been proposed for recommendation by integrating the relationship (link) graphs among users/items into matrix completion (MC). Traditional GMC methods typically adopt graph regularization to impose smoothness priors ... More
Intrinsic Origin of Enhancement of Ferroelectricity in SnTe Ultrathin FilmsMay 10 2018Previous studies showed that, as ferroelectric films become thinner, their Curie temperature (Tc) and polarization below Tc both typically decrease. In contrast, a recent experiment [Chang et al., Science 353, 274 (2016)] observed that atomic-thick SnTe ... More
Exploring the Partially-obscured BLR and Partially-covered NLRFeb 25 2009We have conducted a series of investigations on the geometry of the reddening material in AGNs, which have important implications to the AGN unification and SMBH demography. According to our statistics of partially obscured quasars, we found that SMBHs ... More
First-principles study of FeSe epitaxial films on SrTiO3Oct 29 2015The discovery of high temperature superconductivity in FeSe films on SrTiO3 substrate has inspired great experimental and theoretical interests. First-principles density functional theory calculations, which have played an important role in the study ... More
First-principles study of magnetic frustration in FeSe epitaxial films on SrTiO$_3$Jan 16 2015The effects of electron doping and phonon vibrations on the magnetic properties of monolayer and bilayer FeSe epitaxial films on SrTiO$_3$ have been studied, respectively, using first-principles calculations with van der Waals correction. For monolayer ... More
Investigation of atomic and electronic structures of MgOFeSe studied by the first-principles calculationsSep 19 2013Sep 30 2013In order to assist the search of new superconductors in iron selenide materials by intercalation, we calculate the crystal and electronic structures of MgOFeSe using the first-principles density functional theory. MgOFeSe is isotructural to the parent ... More
Horndeski Gravity and the Violation of Reverse Isoperimetric InequalityMay 24 2017Jun 04 2017We consider Einstein-Horndeski-Maxwell gravity, together with a cosmological constant and multiple Horndeski axions. We construct charged AdS planar black holes in general dimensions where the Horndeski anxions span over the planar directions. We analyse ... More
Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. IV. H$β$ Time Lags and Implications for Super-Eddington AccretionApr 08 2015We have completed two years of photometric and spectroscopic monitoring of a large number of active galactic nuclei (AGNs) with very high accretion rates. In this paper, we report on the result of the second phase of the campaign, during 2013--2014, and ... More
Ground-to-satellite quantum teleportationJul 04 2017An arbitrary unknown quantum state cannot be precisely measured or perfectly replicated. However, quantum teleportation allows faithful transfer of unknown quantum states from one object to another over long distance, without physical travelling of the ... More
Pure leptonic proposal to $W^{+}W^{-}$ excess and neutrino mass generationJul 18 2014We investigate the TeV models for neutrino mass generation as candidate models to explain the recent 2$\sigma$ excess of leptonic $W^{+}W^{-}$ pair production at LHC. Several models with singly charged exotic states that may explain the excess require ... More
Squarkonium, diquarkonium and octetonium at the LHC and their di-photon decaysDec 21 2015Mar 21 2016Motivated by the recent di-photon excess by both ATLAS and CMS collaborations at the LHC, we systematically investigate the production and di-photon decay of onia formed by pair of all possible color exotic scalars in minimal extension. When such scalar ... More
Light Higgsino from $A_t$ Dilemma in Rare $B$-decaysNov 30 2015In the Minimal Supersymmetric Standard Model (MSSM), large chiral symmetry breaking term $A_t$, which plays an important role in Higgs mass, may significantly contribute in flavor changing neutral current (FCNC) processes $B\to X_{s}\gamma$ and $B_{s}\to ... More
Quark jet versus gluon jet: fully-connected neural networks with high-level featuresDec 11 2017May 15 2019Jet identification is one of the fields in high energy physics that machine learning has begun to make an impact. More often than not, convolutional neural networks are used to classify jet images with the benefit that essentially no physics input is ... More
Demonstration of Vector Flow Imaging using Convolutional Neural NetworksMar 11 2019Synthetic Aperture Vector Flow Imaging (SA-VFI) can visualize complex cardiac and vascular blood flow patterns at high temporal resolution with a large field of view. Convolutional neural networks (CNNs) are commonly used in image and video recognition ... More
What if bb does not dominate the decay of the Higgs-like boson?Dec 27 2012The dominant decay mode of standard model Higgs at 126 GeV $b\bar{b}$ suffers from severe SM background at the LHC even in associated productions $Wh_{\rm SM}$ or $Z h_{\rm SM}$. The precision measurement of BR($\phi\to b\bar{b})$ requires more data to ... More
Like-sign Di-lepton Signals in Higgsless Models at the LHCAug 15 2009We study the potential LHC discovery of the Z1 KK gauge boson unitarizing longitudinal W+W- scattering amplitude. In particular, we explore the decay mode Z1->t tbar along with Z1-> W+W- without specifying the branching fractions. We propose to exploit ... More
Collective oscillations of a Bose-Einstein condensate induced by a vortex ringJun 07 2019We study the collective oscillations of three-dimensional Bose-Einstein condensates (BECs) excited by a vortex ring. We identify independent, integrated, and stationary modes of the center-of-mass oscillation of the condensate with respect to the vortex ... More
Outflow and hot dust emission in high redshift quasarsSep 17 2013Sep 25 2013Correlations of hot dust emission with outflow properties are investigated, based on a large z~2 non-broad absorption lines quasar sample built from the Wide-field Infrared Survey and the Sloan Digital Sky Survey data releases. We use the near infrared ... More
Outflow and hot dust emission in broad absorption line quasarsMar 13 2014We have investigated a sample of 2099 broad absorption line (BAL) quasars with z=1.7-2.2 built from the Sloan Digital Sky Survey Data Release Seven and the Wide-field Infrared Survey. This sample is collected from two BAL quasar samples in the literature, ... More
Searching SUSY Leptonic Partner at the CERN LHCJul 04 2012Nov 11 2012Motivated by the observed excess of the di-photon signal in Higgs searches, $\sigma_{\gamma\gamma}/\sigma_{\rm SM}\simeq 1.5$, we argue that models with enhanced $\Gamma(h\to \gamma\gamma)$ alone are the most favorable scenarios when the latest LHC/Tevatron ... More
Ideal Weyl semimetals in the chalcopyrites CuTlSe2, AgTlTe2, AuTlTe2 and ZnPbAs2Mar 03 2016May 17 2016Weyl semimetals are new states of matter which feature novel Fermi arcs and exotic transport phenomena. Based on first-principles calculations, we report that the chalcopyrites CuTlSe2, AgTlTe2, AuTlTe2 and ZnPbAs2 are ideal Weyl semimetals, having largely ... More
Lattice symmetry assisted second order topological superconductors and Majorana patternsDec 28 2018May 09 2019We propose a realization of the lattice symmetry assisted second order topological superconductors with corner Majorana zero modes (MZM) based on two-dimensional topological insulators (2DTI). The lattice symmetry can naturally lead to the anisotropic ... More
Ultrasensitive, high-dynamic-range and broadband strain sensing by time-of-flight detection with femtosecond-laser frequency combsJun 21 2017Ultrahigh-resolution optical strain sensors provide powerful tools in various scientific and engineering fields, ranging from long-baseline interferometers to civil and aerospace industries. Here we demonstrate an ultrahigh-resolution fibre strain sensing ... More
Quasinormal modes of Dirac field perturbation in Reissner-Nordström black hole surrounded by quintessenceOct 27 2009Oct 30 2009The dirac quasinormal modes of the Reissner-Nordstr\"om black hole surrounded by quintessence are investigated using the third WKB approximation. We find that the magnitude of the imaginary part of the quasinormal mode frequencies increases firstly and ... More
Assessing the risk of advanced persistent threatsJul 08 2017Dec 28 2017As a new type of cyber attacks, advanced persistent threats (APTs) pose a severe threat to modern society. This paper focuses on the assessment of the risk of APTs. Based on a dynamic model characterizing the time evolution of the state of an organization, ... More
Testing Technicolor Models in Top Quark Pair Production at High Energy Photon CollidersJul 27 1997Nov 29 1997We study pseudo-Goldstone boson corrections to top quark pair production rates in technicolor models with and without topcolor at the E=0.5 teV and 1.5 TeV photon colliders. We find that, for reasonable ranges of the parameters, the corrections are large ... More
Analysis of the effectiveness of the truth-spreading strategy for inhibiting rumorsMay 17 2017Spreading truths is recognized as a feasible strategy for inhibiting rumors. This paper is devoted to assessing the effectiveness of the truth-spreading strategy. An individual-level rumor-truth spreading model (the generic URTU model) is derived. Under ... More
A discount strategy in word-of-mouth marketing and its assessmentApr 23 2017This paper addresses the discount pricing in word-of-mouth (WOM) marketing. A new discount strategy known as the Infection-Based Discount (IBD) strategy is proposed. The basic idea of the IBD strategy lies in that each customer enjoys a discount that ... More
Cosmological Time Crystals From Einstein-Cubic GravitiesJul 04 2018By including appropriate Riemman cubic invariants, we find that the dynamics of classical time crystals can be straightforwardly realized in Einstein gravity on the FLRW metric. The time reflection symmetry is spontaneously broken in the two vacua with ... More
The damage inflicted by a computer virus: A new estimation methodJun 07 2017This paper addressed the issue of estimating the damage caused by a computer virus. First, an individual-level delayed SIR model capturing the spreading process of a digital virus is derived. Second, the damage inflicted by the virus is modeled as the ... More