Results for "Liang Chen"

total 36621took 0.14s
On the origin of the hard X-Ray excess of high-synchrotron-peaked BL Lac object Mrk 421Jun 14 2017Jul 26 2017For the first time, Kataoka \& Stawarz reported a clear detection of a hard X-ray excess, above $\gtrsim$20 keV, in the high-synchrotron-peaked BL Lac object Mrk 421. We find that this feature may not be produced by the low-energy part of the same electron ... More
On the jet properties of the gamma-ray loud active galactic nucleiMar 14 2018Apr 12 2018Based on broadband spectral energy distribution (SEDs), we estimate the jet physical parameters of 1392 $\gamma$-ray-loud active galactic nuclei (AGNs), the largest sample so far. The (SED) jet power and magnetization parameter are derived for these AGNs. ... More
Strongly Goldie DimensionOct 09 2005Let $R$ be an associative ring with identity. A unital right $R$-module $M$ is called strongly finite dimensional if Sup$\{{\rm G.dim} (M/N) | N\leq M\} < +\infty$. Properties of strongly finite dimensional modules are explored. It is also proved that: ... More
Surface Spectral Function of Momentum-dependent Pairing Potentials in a Topological Insulator: Application to Cu$_x$Bi$_2$Se$_3$Mar 12 2012Mar 31 2012We propose three possible momentum-dependent pairing potentials for candidate of topological superconductor (for example Cu$_x$Bi$_2$Se$_3$), and calculate the surface spectral function and surface density of state with these pairing potentials. We find ... More
On countably $Σ$-C2 ringsMay 23 2010Let $R$ be a ring. $R$ is called a right countably $\Sigma$-C2 ring if every countable direct sum copies of $R_{R}$ is a C2 module. The following are equivalent for a ring $R$: (1) $R$ is a right countably $\Sigma$-C2 ring. (2) The column finite matrix ... More
Rotation Anomaly and Topological Crystalline InsulatorsSep 06 2017We show that in the presence of $n$-fold rotation symmetries and time-reversal symmetry, the number of fermion flavors must be a multiple of $2n$ ($n=2,3,4,6$) on two-dimensional lattices, a stronger version of the well-known fermion doubling theorem ... More
Small Injective RingsMay 21 2005Let $R$ be a ring, a right ideal $I$ of $R$ is called small if for every proper right ideal $K$ of $R$, $I+K\neq R$. A ring $R$ is called right small injective if every homomorphism from a small right ideal to $R_{R}$ can be extended to an $R$-homomorphism ... More
Non-naturally reductive Einstein metrics on the compact simple Lie group $F_4$Nov 21 2013Based on the representation theory and the study on the involutions of compact simple Lie groups, we show that $F_4$ admits non-naturally reductive Einstein metrics.
Casimir interaction between topological insulators with finite surface band gapMay 18 2011Jul 05 2011Casimir interaction between topological insulators with opposite topological magnetoelectric polarizabilities and finite surface band gaps has been investigated. For large surface band gap limit$(m\rightarrow\infty)$, we can obtain results given in [Phys. ... More
A Note on Quasi-Frobenius RingsApr 05 2005The Faith-Menal conjecture says that every strongly right $Johns$ ring is $QF$. The conjecture is also equivalent to say every right noetherian left $FP$-injective ring is $QF$. In this short article, we show that the conjecture is true under the condition(a ... More
New classes of topological crystalline insulators with unpinned surface Dirac conesJan 22 2015We theoretically predict two new classes of three-dimensional topological crystalline insulators (TCIs), which have an odd number of unpinned surface Dirac cones protected by crystal symmetries. The first class is protected by a single glide plane symmetry; ... More
Critical surface band gap of repulsive Casimir interaction between three dimensional topological insulators at finite temperatureNov 18 2011We generalize the calculation of Casimir interaction between topological insulators with opposite topological magnetoelectric polarizabilities and finite surface band gaps to finite Temperature cases. We find that finite temperature quantitatively depress ... More
Minimal Conductivity of Topological Surface States with Magnetic ImpuritiesMay 22 2010In this paper we use the semiclassical Boltzmann equation to investigate the transport properties of Dirac fermion on the surface of topological insulator with magnetic impurities. The results obtained show that there is also a minimal conductivity in ... More
Is Low-Frequency-Peaked BL Lac Object OJ 287 a TeV Emitter?Sep 13 2010It is well known that there are only two low-frequency-peaked BL Lac objects (LBLs: BL Lacertae and S5 0716+714) and one flat spectrum radio quasar (FSRQ: 3C 279) among more than 30 active galactic nuclei (AGNs) with detected TeV emissions. We study the ... More
Quantum Phase Transition in Finite-Size Lipkin-Meshkov-Glick ModelAug 11 2006Lipkin model of arbitrary particle-number N is studied in terms of exact differential-operator representation of spin-operators from which we obtain the low-lying energy spectrum with the instanton method of quantum tunneling. Our new observation is that ... More
Frozen water waves over rough topographical bottomsApr 28 2004The propagation of surface water waves over rough topographical bottoms is investigated by the multiple scattering theory. It is shown that the waves can be localized spatially through the process of multiple scattering and wave interference, a peculiar ... More
Kondo temperature of Anderson impurity model in a quantum wire with spin-orbit couplingNov 15 2017We use two different methods, the Hirsch-Fye quantum Monte Carlo simulation and the slave-boson mean field analysis to estimate the effect of spin-orbit coupling on the Kondo temperature in a quantum wire. In quantum Monte Carlo simulation, we calculate ... More
A Fibrational Approach to Automata TheoryApr 10 2015For predual categories C and D we establish isomorphisms between opfibrations representing local varieties of languages in C, local pseudovarieties of D-monoids, and finitely generated profinite D-monoids. The global sections of these opfibrations are ... More
Electronic band gap and transport in Fibonacci quasi-periodic graphene superlatticeNov 07 2011We investigate electronic band gap and transport in Fibonacci quasi-periodic graphene superlattice. It is found that such structure can possess a zero-$\bar{k}$ gap which exists in all Fibonacci sequences. Different from Bragg gap, zero-$\bar{k}$ gap ... More
Schützenberger Products in a CategoryMay 06 2016The Sch\"utzenberger product of monoids is a key tool for the algebraic treatment of language concatenation. In this paper we generalize the Sch\"utzenberger product to the level of monoids in an algebraic category $\mathscr{D}$, leading to a uniform ... More
Comments on "Quantum theory cannot consistently describe the use of itself"Oct 02 2018Mar 16 2019Recently, a delicately designed Gedankenexperiment was proposed to check the self-consistence of quantum theory in the description of the agents who are using this theory. It was demonstrated that the quantum theory is inconsistent. Here a critical improvement ... More
Ground-State Properties for Coupled Bose-Einstein Condensates inside a Cavity Quantum ElectrodynamicsOct 29 2007We analytically investigate the ground-state properties of two-component Bose-Einstein condensates with few &#8312;&#8311;Rb atoms inside a high-quality cavity quantum electrodynamics. In the SU(2) representation for atom, this quantum system can be realized ... More
Uncertainty-Complementarity Balance as a General Constraint on Non-localityAug 20 2018We propose an uncertainty-complementarity balance relation and build quantitative connections among non-locality, complementarity, and uncertainty. Our balance relation, which is formulated in a theory-independent manner, states that for two measurements ... More
X-ray Radiation Mechanisms and Beaming Effect of Hot Spots and Knots in Active Galactic Nuclear JetsDec 13 2009The observed radio-optical-X-ray spectral energy distributions (SEDs) of 22 hot spots and 45 knots in the jets of 35 active galactic nuclei are complied from literature and modeled with single-zone lepton models. It is found that the observed luminosities ... More
Quantization of the Lie bialgebra of string topologyFeb 12 2009Feb 24 2009Let M be a smooth, simply-connected, closed oriented manifold, and LM the free loop space of M. Using a Poincare duality model for M, we show that the reduced equivariant homology of LM has the structure of a Lie bialgebra, and we construct a Hopf algebra ... More
Momentum distribution and tunneling density of states of one-dimensional Fermonic SU(N) Hubbard modelNov 27 2018We study the one-dimensional Fermionic Hubbard model with SU(N) spin symmetry in the incommensurate filling case. The basic properties of Green's function, momentum distribution and tunneling density of states of the system at low temperature are studied ... More
Tunable Weyl fermions and Fermi arcs in magnetized topological crystalline insulatorsApr 13 2016Based on $k\cdot p$ analysis and realistic tight-binding calculations, we find that time-reversal-breaking Weyl semimetals can be realized in magnetically-doped (Mn, Eu, Cr etc.) Sn$_{1-x}$Pb$_x$(Te,Se) class of topological crystalline insulators. All ... More
Empirical Potential Function for Simplified Protein Models: Combining Contact and Local Sequence-Structure DescriptorsJan 20 2006An effective potential function is critical for protein structure prediction and folding simulation. Simplified protein models such as those requiring only $C_\alpha$ or backbone atoms are attractive because they enable efficient search of the conformational ... More
Statistical Geometry of Packing Defects of Lattice Chain Polymer from Enumeration and Sequential Monte Carlo MethodMar 07 2002Voids exist in proteins as packing defects and are often associated with protein functions. We study the statistical geometry of voids in two-dimensional lattice chain polymers. We define voids as topological features and develop a simple algorithm for ... More
Stochastic Geometry Analysis of Multi-Antenna Two-Tier Cellular NetworksJan 15 2016In this paper, we study the key properties of multi-antenna two-tier networks under different system configurations. Based on stochastic geometry, we derive the expressions and approximations for the users' average data rate. Through the more tractable ... More
Partitioned Sampling of Public Opinions Based on Their Social DynamicsOct 18 2015Nov 25 2016Public opinion polling is usually done by random sampling from the entire population, treating individual opinions as independent. In the real world, individuals' opinions are often correlated, e.g., among friends in a social network. In this paper, we ... More
Non-equilibrium dynamics of an ultracold Bose gas under a multi-pulsed quantum quench in interactionJan 28 2015We investigate the nonequilibrium dynamical properties of a weakly-interacting Bose gas at zero temperature under the multi-pulsed quantum quench in interaction by calculating one-body, two-body correlation functions and Tan's contact of the model system. ... More
Area Spectral Efficiency Analysis and Energy Consumption Minimization in Multi-Antenna Poisson Distributed NetworksJan 07 2016This paper aims at answering two fundamental questions: how area spectral efficiency (ASE) behaves with different system parameters; how to design an energy-efficient network. Based on stochastic geometry, we obtain the expression and a tight lower-bound ... More
Orbital Insulators and Orbital Order-disorder Induced Metal-Insulator Transition in Transition-Metal OxidesJan 10 2005Sep 25 2007The role of orbital ordering on metal-insulator transition of transition-metal oxides is investigated by the cluster self-consistent field approach in the strong correlation regime. A clear dependence of the insulating gap on the orbital order parameter ... More
Lower and upper bounds for entanglement of Rényi-$α$ entropyApr 11 2016Dec 24 2016Entanglement R\'enyi-$\alpha$ entropy is an entanglement measure. It generalizes the entanglement of formation, and they coincide when $\alpha$ tends to 1. We derive analytical lower and upper bounds for the entanglement R\'enyi-$\alpha$ entropy of arbitrary ... More
Feasibility study on the least square method for fitting non-Gaussian noise dataMay 03 2017Jun 13 2017This study is to investigate the feasibility of least square method in fitting non-Gaussian noise data. We add different levels of the two typical non-Gaussian noises, L\'evy and stretched Gaussian noises, to exact value of the selected functions including ... More
Vectorial Resilient $PC(l)$ of Order $k$ Boolean Functions from AG-CodesJun 02 2006Sep 19 2006Propagation criterion of degree $l$ and order $k$ ($PC(l)$ of order $k$) and resiliency of vectorial Boolean functions are important for cryptographic purpose (see [1, 2, 3,6, 7,8,10,11,16]. Kurosawa, Stoh [8] and Carlet [1] gave a construction of Boolean ... More
Development of novel one-shot full-field surface profilometer using chromatic confocal microscopyDec 17 2018A novel full-field surface profilometer using diffractive-based chromatic confocal microscopy and area-scan spectral sensing is developed. A normalized cross correlation algorithm was developed to establish a spectrum-depth response curve. A measuring ... More
The decomposition of a Lie group with a left invariant pseudo-Riemannian metric and the uniquenessMar 10 2011Mar 15 2012In this paper, we discuss the decomposition of a Lie group with a left invariant pseudo-Riemannian metric and the uniqueness. In fact, it is a decomposition of a Lie group into totally geodesic sub-manifolds which is different from the De Rham decomposition ... More
Moment-generating function method used to accurately evaluate the impact of the linearized optical noise amplified by EDFAsJul 13 2012Jun 18 2013In a nonlinear optical fiber communication (OFC) system with signal power much stronger than noise power, the noise field in the fiber can be described by linearized noise equation (LNE). In this case, the noise impact on the system performance can be ... More
On the Products $(1^\ell+1)(2^\ell+1)\cdots (n^\ell +1)$, IINov 22 2013In this paper, the following results are proved: (i) For any odd integer $\ell$ with at most two distinct prime factors and any positive integer $n$, the product $(1^\ell+1)(2^\ell+1)\cdots (n^\ell +1)$ is not a powerful number; (ii) For any integer $r\ge ... More
A Curve-based Material Recognition Method in MeV Dual-energy X-ray Imaging SystemNov 28 2014High energy dual-energy X-ray Digital Radiography(DR) imaging is mainly used in material recognition of the cargo inspection. We introduce the development history and the principle of the technology and describe the data process flow of our system. The ... More
On unusual narrow transmission bands for a multi-layered periodic structure containing left-handed materialsNov 01 2002Nov 03 2002A multi-layered structure consisting of alternate right-handed material (RHM) and left-handed material (LHM)is considered and the unusual narrow transmission bands are explained as the competitive results of the Bragg condition and the transparent condition. ... More
Ground state degeneracy in quantum spin systems protected by crystal symmetriesMay 25 2017Aug 03 2017We develop a no-go theorem for two-dimensional bosonic systems with crystal symmetries: if there is a half-integer spin at a rotation center, where the point-group symmetry is $\mathbb D_{2,4,6}$, such a system must have a ground-state degeneracy protected ... More
Total positivity of recursive matricesJan 21 2016Let $A=[a_{n,k}]_{n,k\ge 0}$ be an infinite lower triangular matrix defined by the recurrence $$a_{0,0}=1,\quad a_{n+1,k}=r_{k}a_{n,k-1}+s_{k}a_{n,k}+t_{k+1}a_{n,k+1},$$ where $a_{n,k}=0$ unless $n\ge k\ge 0$ and $r_k,s_k,t_k$ are all nonnegative. Many ... More
Information scrambling in chaotic systems with dissipationFeb 13 2018Chaotic dynamics in closed local quantum systems scrambles quantum information, which is manifested quantitatively in the decay of the out-of-time-ordered correlators (OTOC) of local operators. How is information scrambling affected when the system is ... More
The central engines of two unusual radio-intermediate/quiet active galactic nuclei: III Zw 2 and PG 1407+265Jan 21 2012Jan 24 2012We use the accretion disk/corona+jet model to fit the multi-band spectral energy distributions (SEDs) of two unusual radio-intermediate/quiet quasars. It is found that the optical/UV emission of III Zw 2 is probably dominated by the emission from the ... More
Spin-spin interaction in the bulk of topological insulatorsNov 12 2013We apply mean-field theory and Hirsch-Fye quantum Monte Carlo method to study the spin-spin interaction in the bulk of three-dimensional topological insulators. We find that the spin-spin interaction has three different components: the longitudinal, the ... More
The three primary colors of mobile systemsMar 11 2016In this paper, we present the notion of "mobile 3C systems in which the "Communications", "Computing", and "Caching" (i.e., 3C) make up the three primary resources/funcationalties, akin to the three primary colors, for a mobile system. We argue that in ... More
Momentum distribution and tunneling density of states of one-dimensional Fermonic SU(N) Hubbard modelNov 27 2018Mar 19 2019We study the one-dimensional Fermionic Hubbard model with SU(N) spin symmetry in the incommensurate filling case. The basic properties of Green's function, momentum distribution and tunneling density of states of the system at low temperature are studied ... More
Learning-based Automatic Parameter Tuning for Big Data Analytics FrameworksAug 17 2018Big data analytics frameworks (BDAFs) have been widely used for data processing applications. These frameworks provide a large number of configuration parameters to users, which leads to a tuning issue that overwhelms users. To address this issue, many ... More
Thermodynamics of Two-impurity Anderson Model with Dzyaloshinskii-Moriya InteractionJun 28 2017Jun 30 2017In this work, we use the numerical renormalization group (NRG) theory to study the thermodynamics of the two-impurity Anderson model. Two different methods are used to estimate the effect of the Dzyaloshiskii-Moriya (DM) interaction on the variation of ... More
Long-range Order in One-dimensional Spinless Fermi Gas with Attractive Dipole-Dipole InteractionJun 04 2013Feb 09 2014One-dimensional spinless Fermi gas with attractive dipole-dipole interaction is investigated. Results obtained show when the interaction is weak, the excitation spectrum is linear and the superconducting correlation function decays as power law, indicating ... More
A Note on the Convergence of ADMM for Linearly Constrained Convex Optimization ProblemsJul 08 2015Feb 22 2016This note serves two purposes. Firstly, we construct a counterexample to show that the statement on the convergence of the alternating direction method of multipliers (ADMM) for solving linearly constrained convex optimization problems in a highly influential ... More
An Efficient Inexact Symmetric Gauss-Seidel Based Majorized ADMM for High-Dimensional Convex Composite Conic ProgrammingJun 02 2015Mar 17 2016In this paper, we propose an inexact multi-block ADMM-type first-order method for solving a class of high-dimensional convex composite conic optimization problems to moderate accuracy. The design of this method combines an inexact 2-block majorized semi-proximal ... More
A fourth-order Runge-Kutta in the interaction picture method for coupled nonlinear Schrodinger equationMar 17 2010A fourth-order Runge-Kutta in the interaction picture (RK4IP) method is presented for solving the coupled nonlinear Schrodinger equation (CNLSE) that governs the light propagation in optical fibers with randomly varying birefringence. The computational ... More
Multi-user Multi-task Offloading and Resource Allocation in Mobile Cloud SystemsMar 17 2018Aug 08 2018We consider a general multi-user Mobile Cloud Computing (MCC) system where each mobile user has multiple independent tasks. These mobile users share the computation and communication resources while offloading tasks to the cloud. We study both the conventional ... More
Resource Sharing of a Computing Access Point for Multi-user Mobile Cloud Offloading with Delay ConstraintsNov 30 2017Mar 16 2018We consider a mobile cloud computing system with multiple users, a remote cloud server, and a computing access point (CAP). The CAP serves both as the network access gateway and a computation service provider to the mobile users. It can either process ... More
Normalized Total Gradient: A New Measure for Multispectral Image RegistrationFeb 15 2017Image registration is a fundamental issue in multispectral image processing. In filter wheel based multispectral imaging systems, the non-coplanar placement of the filters always causes the misalignment of multiple channel images. The selective characteristic ... More
Out-of-time-ordered correlators in many-body localized systemsAug 03 2016Dec 10 2016In many-body localized systems, propagation of information forms a light cone that grows logarithmically with time. However, local changes in energy or other conserved quantities typically spread only within a finite distance. Is it possible to detect ... More
Floquet band structure of a semi-Dirac systemSep 26 2017In this work we use Floquet-Bloch theory to study the influence of circularly and linearly polarized light on two-dimensional band structures with semi-Dirac band touching points, taking the anisotropic nearest neighbor hopping model on the honeycomb ... More
Geometric phase in the Kitaev honeycomb model and scaling behavior at critical pointsOct 22 2011In this paper a geometric phase of the Kitaev honeycomb model is derived and proposed to characterize the topological quantum phase transition. The simultaneous rotation of two spins is crucial to generate the geometric phase for the multi-spin in a unit-cell ... More
Critical Property of Geometric Phase in the Dicke ModelAug 28 2006We obtain the ground-state energy level and associated geometric phase in the Dicke model analytically by means of the Holstein-Primakoff transformation and the boson expansion approach in the thermodynamic limit. The non-adiabatic geometric phase induced ... More
Pair Superfluid and Supersolid of Correlated Hard-Core Bosons on a Triangular LatticeApr 15 2012We have systematically studied the hard-core Bose-Hubbard model with correlated hopping on a triangular lattice using density-matrix renormalization group method. A rich ground state phase diagram is determined. In this phase diagram there is a supersolid ... More
Orthorhombic crystalline field splitting on orbital and magnetic orders in KCuF$_3$Sep 28 2005Magnetic and orbital structures in KCuF$_{3}$ are revisited by the cluster self-consistent field approach developed recently. We clearly showed that due to the inherent frustration, the ground state of the system with the superexchange and Jahn-Teller ... More
General Monogamy Relations for Multiqubit W-class States in terms of negativity and squared Rényi-$α$ entanglementMar 28 2017Apr 24 2017For multipartite entangled states, entanglement monogamy is an important property. We investigate the monogamy relations for multiqubit generalized W-class states. We present new analytical monogamy inequalities satisfied by the $x$-th power of the dual ... More
Sensitivity of parameter estimation near the exceptional point of a non-Hermitian systemSep 15 2018The exceptional points of non-Hermitian systems, where $n$ different energy eigenstates merge into an identical one, have many intriguing properties that have no counterparts in Hermitian systems. In particular, the $\epsilon^{1/n}$ dependence of the ... More
Development of novel one-shot full-field surface profilometer using chromatic confocal microscopyDec 17 2018Apr 11 2019A novel full-field surface profilometer using diffractive-based chromatic confocal microscopy and area-scan spectral sensing is developed. A normalized cross correlation algorithm was developed to establish a spectrum-depth response curve. A measuring ... More
A New CGAN Technique for Constrained Topology Design OptimizationJan 22 2019This paper presents a new conditional GAN (named convex relaxing CGAN or crCGAN) to replicate the conventional constrained topology optimization algorithms in an extremely effective and efficient process. The proposed crCGAN consists of a generator and ... More
Smart Streaming for Online Video ServicesJul 17 2013Apr 10 2014Bandwidth consumption is a significant concern for online video service providers. Practical video streaming systems usually use some form of HTTP streaming (progressive download) to let users download the video at a faster rate than the video bitrate. ... More
Sparse Representation of a Blur Kernel for Blind Image RestorationDec 14 2015Blind image restoration is a non-convex problem which involves restoration of images from an unknown blur kernel. The factors affecting the performance of this restoration are how much prior information about an image and a blur kernel are provided and ... More
Vorticity, Gyroscopic precession, and Spin-Curvature ForceOct 23 2012Feb 11 2013In investigating the relation between vorticity and gyroscopic precession, we calculate the vorticity vector in Godel, Kerr, Lewis, Schwarzschild, Minkowski metric and find out the vorticity vector of the specific observers is the angular velocity of ... More
Total positivity of Riordan arraysJan 21 2016We present sufficient conditions for total positivity of Riordan arrays. As applications we show that many well-known combinatorial triangles are totally positive and many famous combinatorial numbers are log-convex in a unified approach.
Liquid structure changes of Bi under different melt statesNov 23 2015Aug 26 2018This paper is focused on the relationship between solidification and melt sates. An abnormal change which takes place at 744 C from 84 to 120 min indicated a liquid-liquid structure transition in pure Bi melt. Based on liquid-liquid structure transition, ... More
Object Recognition Based on Amounts of Unlabeled DataMar 25 2016This paper proposes a novel semi-supervised method on object recognition. First, based on Boost Picking, a universal algorithm, Boost Picking Teaching (BPT), is proposed to train an effective binary-classifier just using a few labeled data and amounts ... More
A three-operator splitting perspective of a three-block ADMM for convex quadratic semidefinite programming and extensionsJul 05 2018In recent years, several convergent multi-block variants of the alternating direction method of multipliers (ADMM) have been proposed for solving the convex quadratic semidefinite programming via its dual, which is naturally a 3-block separable convex ... More
Bounds for entanglement of formation of two mode squeezed thermal statesMar 24 2003The upper and lower bounds of entanglement of formation are given for two mode squeezed thermal state. The bounds are compared with other entanglement measure or bounds. The entanglement distillation and the relative entropy of entanglement of infinitive ... More
Non-trivial $m$-quasi-Einstein metrics on simple Lie groupsOct 30 2013Jul 19 2014We call a metric $m$-quasi-Einstein if $Ric_X^m$, which replaces a gradient of a smooth function $f$ by a vector field $X$ in $m$-Bakry-Emery Ricci tensor, is a constant multiple of the metric tensor. It is a generalization of Einstein metrics which contains ... More
Non-trivial $m$-quasi-Einstein metrics on quadratic Lie groupsJan 09 2014Jun 30 2015We call a metric $m$-quasi-Einstein if $Ric_X^m$ (a modification of the $m$-Bakry-Emery Ricci tensor in terms of a suitable vector field $X$) is a constant multiple of the metric tensor. It is a generalization of Einstein metrics which contains Ricci ... More
Nonlinear optical properties in a quantum well with the hyperbolic confinement potentialNov 11 2011We have performed theoretical calculation of the nonlinear optical properties in a quantum well (QW) with the hyperbolic confinement potential. Calculation results reveal that the transition energy, oscillator strength, second-order nonlinear optical ... More
Potential function of simplified protein models for discriminating native proteins from decoys: Combining contact interaction and local sequence-dependent geometryJul 22 2004An effective potential function is critical for protein structure prediction and folding simulation. For simplified models of proteins where coordinates of only $C_\alpha$ atoms need to be specified, an accurate potential function is important. Such a ... More
Constraints on minimum electron Lorentz factor and matter content of jets for a sample of bright Fermi blazarsSep 10 2014We fit the (quasi-)simultaneous multi-waveband spectral energy distributions (SEDs) for a sample of low-synchrotron-peaked (LSP) blazars with a one-zone leptonic model. The seed photons that predominantly come from broad line region (BLR) and infrared ... More
Mining Circumgalactic Baryons in the Low-Redshift UniverseFeb 14 2014Sep 11 2014(Abridged) This paper presents an absorption-line study of the multiphase circumgalactic medium (CGM) based on observations of Lya, CII, CIV, SiII, SiIII, and SiIV absorption transitions in the vicinities of 195 galaxies at redshift z<0.176. The galaxy ... More
Fake View Analytics in Online Video ServicesDec 18 2013Online video-on-demand(VoD) services invariably maintain a view count for each video they serve, and it has become an important currency for various stakeholders, from viewers, to content owners, advertizers, and the online service providers themselves. ... More
Invariant Einstein metrics on three-locally-symmetric spacesNov 11 2014Nov 13 2014In this paper, we classify three-locally-symmetric spaces for a connected, compact and simple Lie group. Furthermore, we give the classification of invariant Einstein metrics on these spaces.
Weighted inequalities of bilinear rough singular integralsAug 27 2017We establish a quantitative weighted inequality for the bilinear rough singular integral, where the bound is controlled by the cube of the weight constant.
A derivation of the entropy-based relativistic smoothed particle hydrodynamics by variational principleApr 19 2017Jul 26 2017In this work, a second order smoothed particle hydrodynamics is derived for the study of relativistic heavy ion collisions. The hydrodynamical equation of motion is formulated in terms of the variational principle. In order to describe the fluid of high ... More
A Generalized Alternating Direction Method of Multipliers with Semi-Proximal Terms for Convex Composite Conic ProgrammingJul 21 2015Jan 16 2018In this paper, we propose a generalized alternating direction method of multipliers (ADMM) with semi-proximal terms for solving a class of convex composite conic optimization problems, of which some are high-dimensional, to moderate accuracy. Our primary ... More
A New CGAN Technique for Constrained Topology Design OptimizationJan 22 2019Apr 01 2019This paper presents a new conditional GAN (named convex relaxing CGAN or crCGAN) to replicate the conventional constrained topology optimization algorithms in an extremely effective and efficient process. The proposed crCGAN consists of a generator and ... More
Long-range self-interacting dark matter in the SunMay 15 2015Dec 11 2015We investigate the implications of the long-rang self-interaction on both the self-capture and the annihilation of the self-interacting dark matter (SIDM) trapped in the Sun. Our discussion is based on a specific SIDM model in which DM particles self-interact ... More
Cracking the invisible cloak by using the temporal steering inequalityApr 16 2015Invisible cloaks provide a way to hide an object under the detection of waves. A perfect cloak guides the incident waves through the cloaking shell without any distortion. In most cases, some important quantum degrees of freedom, e.g. electron spin or ... More
Probing Sound Speed of an Optically-Trapped Bose Gas with Periodically Modulated Interactions by Bragg SpectroscopyDec 01 2014A Bose-Einstein condensate (BEC) with periodically modulated interactions (PMI) has emerged as a novel kind of periodic superfluid, which has been recently experimentally created using optical Feshbach resonance. In this paper, we are motivated to investigate ... More
Overshooting in the core helium burning stage of a $30M_{\odot}$ star using the $k$-$ω$ modelNov 16 2018Overshooting and semiconvection are among the most uncertainties in the evolution of massive stars. Complete mixing over a certain distance beyond the convective boundary (Stothers \& Chin 1985) and an exponentially decaying diffusion outside the convection ... More
Importance of chirality and reduced flexibility of protein side chains: A study with square and tetrahedral lattice modelsApr 10 2004In simple models side chains are often represented implicitly (e.g., by spin-states) or simplified as one atom. We study side chain effects using square lattice and tetrahedral lattice models, with explicitly side chains of two atoms. We distinguish effects ... More
Formation of Extremely Low-mass White Dwarfs in Double DegeneratesDec 18 2018Feb 28 2019Extremely low-mass white dwarfs (ELM WDs) are helium WDs with a mass less than $\sim$$0.3\rm\;M_\odot$. Most ELM WDs are found in double degenerates (DDs) in the ELM Survey led by Brown and Kilic. These systems are supposed to be significant gravitational-wave ... More
Knowledge-Embedded Routing Network for Scene Graph GenerationMar 08 2019To understand a scene in depth not only involves locating/recognizing individual objects, but also requires to infer the relationships and interactions among them. However, since the distribution of real-world relationships is seriously unbalanced, existing ... More
Knowledge-Embedded Representation Learning for Fine-Grained Image RecognitionJul 02 2018Humans can naturally understand an image in depth with the aid of rich knowledge accumulated from daily lives or professions. For example, to achieve fine-grained image recognition (e.g., categorizing hundreds of subordinate categories of birds) usually ... More
Topological nodal line semimetals with and without spin-orbital couplingJun 10 2015Jul 22 2015We theoretically study three-dimensional topological semimetals (TSMs) with nodal lines protected by crystalline symmetries. Compared with TSMs with point nodes, e.g., Weyl semimetals and Dirac semimetals, where the conduction and the valence bands touch ... More
Unusual behavior of sound velocity of a Bose gas in an optical superlattice at quasi-one-dimensionDec 20 2014A Bose gas trapped in a one-dimensional optical superlattice has emerged as a novel superfluid characterized by tunable lattice topologies and tailored band structures. In this work, we focus on the propagation of sound in such a novel system and have ... More
A GPU Poisson-Fermi Solver for Ion Channel SimulationsNov 11 2017The Poisson-Fermi model is an extension of the classical Poisson-Boltzmann model to include the steric and correlation effects of ions and water treated as nonuniform spheres in aqueous solutions. Poisson-Boltzmann electrostatic calculations are essential ... More