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The Number of Fractional Powers in the Fibonacci WordNov 28 2018The Fibonacci word is the fixed point beginning with the letter $a$ of morphism $\sigma(a)=ab$, $\sigma(b)=a$ defined over the alphabet $\{a,b\}$. In this paper, we get explicit expression of the number of distinct fractional powers in each factor of ... More

Envelope Words and the Reflexivity of the Return Word Sequences in the Period-doubling SequenceMar 21 2017We consider the infinite one-sided sequence over alphabet $\{a,b\}$ generated by the period-doubling substitution $\sigma(a)=ab$ and $\sigma(b)=aa$, denoted by $\mathbb{D}$. Let $r_p(\omega)$ be the $p$-th return word of factor $\omega$. The main result ... More

The numbers of powers in the Tribonacci sequenceSep 21 2016The Tribonacci sequence $\mathbb{T}$ is the fixed point of the substitution $\sigma(a)=ab$, $\sigma(b)=ac$, $\sigma(c)=a$. The prefix of $\mathbb{T}$ of length $n$ is denoted by $\mathbb{T}[1,n]$. The main result is threefold, we give: (1) explicit expressions ... More

Black Hole Mass Formula Is a Vanishing Noether ChargeJan 31 2002The Noether current and its variation relation with respect to diffeomorphism invariance of gravitational theories have been derived from the horizontal variation and vertical-horizontal bi-variation of the Lagrangian, respectively. For Einstein's GR ... More

A CUDA-Based Real Parameter Optimization BenchmarkJul 29 2014Benchmarking is key for developing and comparing optimization algorithms. In this paper, a CUDA-based real parameter optimization benchmark (cuROB) is introduced. Test functions of diverse properties are included within cuROB and implemented efficiently ... More

Non-Gaussianity in KKLMMT modelApr 16 2005May 02 2005We investigate the non-Gaussianity of the brane inflation which happens in the same throat in the framework of the generalized KKLMMT model. When we take the constraints from non-Gaussianity into account, various consequences are discussed including the ... More

Neutrino phenomenology of a high scale supersymmetry modelAug 31 2018Jan 03 2019CP violation in the lepton sector, and other aspects of neutrino physics, are studied within a high scale supersymmetry model. In addition to the sneutrino vacuum expectation values (VEVs), the heavy vector-like triplet also contributes to neutrino masses. ... More

Variations in Discrete Mechanics and Field TheoryDec 27 2001Some problems on variations are raised for classical discrete mechanics and field theory and the difference variational approach with variable step-length is proposed motivated by Lee's approach to discrete mechanics and the difference discrete variational ... More

Preparation and characterization of Bismaleimide resin/titania nanocomposites via sol-gel processApr 26 2013Bismaleimide (BMI) resin/ titania nanocomposites were synthesized from allylated-phenolic modified bismaleimide resin and TiO2 via the sol-gel process of tetrabutyltitanate (Ti(OnBu)4, TBT). These nanocomposite materials were characterized by FT-IR, XRD, ... More

One conjecture and two observations on de Sitter spaceMay 03 2005Apr 24 2006We propose that the state represented by the Nariai black hole inside de Sitter space is the ground state of the de Sitter gravity, while the pure de Sitter space is the maximal energy state. With this point of view, we investigate thermodynamics of de ... More

Novel Bismaleimide Resin/Silsesquioxane and Titania Nanocomposites by the Sol-Gel Process: the Preparation, Morphology, Thermal and Thermo-mechanical PropertiesApr 01 2013Bismaleimide(BMI) resin/silsesquioxane or titania nanocomposites were synthesized from bismaleimide resin and SiO3/2 or TiO2 via the sol-gel process of N-{\gamma}-triethoxylsilylpropyl-maleamic acid (TESPMA) or tetrabutyltitanate (Ti(OnBu)4, TBT), respectively, ... More

Internet Resource Pricing Models, Mechanisms, and MethodsApr 11 2011With the fast development of video and voice network applications, CDN (Content Distribution Networks) and P2P (Peer-to-Peer) content distribution technologies have gradually matured. How to effectively use Internet resources thus has attracted more and ... More

On Torsion and Nieh-Yan FormMay 07 1998Using the well-known Chern-Weil formula and its generalization, we systematically construct the Chern-Simons forms and their generalization induced by torsion as well as the Nieh-Yan (N-Y) forms. We also give an argument on the vanishing of integration ... More

Two Particle Physics Models With Spontaneous CP Violation From Gauge Theory On Discrete GroupJan 23 1998Based on the differential calculus and the gauge theory on discrete groups, we reconstruct two physics models with spontaneous CP violation: (1) The Georgi-Glashow-Lee model with two Higgs triplets; (2) The Weinberg-Salam-Branco model with three Higgs ... More

General Volume-Preserving Mechanical SystemsAug 23 2002In this letter, we present the general form of equations that generate a volume-preserving flow on a symplectic manifold (M, \omega). It is shown that every volume-preserving flow has some 2-forms acting the role of the Hamiltonian functions in the Hamiltonian ... More

Effect of the Early Reionization on the Cosmic Microwave Background and Cosmological Parameter EstimatesApr 27 2017May 12 2017The early reionization (ERE) is supposed to be a physical process which happens after recombination, but before the instantaneous reionization caused by the first generation of stars. We investigate the effect of the ERE on the temperature and polarization ... More

Injection locking of optomechanical oscillators via acoustic wavesDec 08 2017Injection locking is a powerful technique for synchronization of oscillator networks and controlling the phase and frequency of individual oscillators using similar or other types of oscillators. Here, we present the first demonstration of injection locking ... More

How the Dark Energy Can Reconcile \textit{Planck} with Local Determination of the Hubble ConstantJun 20 2016Jun 21 2016We try to reconcile the tension between the local 2.4\% determination of Hubble constant and its global determination by $\textit{Planck}$ CMB data and BAO data through modeling the dark energy variously. We find that the chi-square is significantly reduced ... More

Improving Object Detection with Inverted AttentionMar 28 2019Improving object detectors against occlusion, blur and noise is a critical step to deploy detectors in real applications. Since it is not possible to exhaust all image defects through data collection, many researchers seek to generate hard samples in ... More

Fast analysis of spherical metasurfaces using vector wave function expansionNov 01 2018Modeling of spherical metasurfaces using Generalized Sheet Transition Conditions (GSTCs) and Vector Wave Function (VWF) expansion is presented. The fields internal and external to the metasurface is expanded in terms of spherical VWFs and unknown coefficients. ... More

Simulation of Circular Cylindrical Metasurfaces using GSTC-MoMApr 10 2018A modeling of circular cylindrical metasurfaces using Method of Moments (MoM) based on Generalized Sheet Transition Conditions (GSTCs) is presented. GSTCs are used to link the integral equations for fields on the inner and outer contour of the cylindrical ... More

Constraints on the neutrino mass and mass hierarchy from cosmological observationsDec 18 2015Mar 24 2016Considering the mass splitting between three active neutrinos, we represent the new constraints on the sum of neutrino mass $\sum m_\nu$ by updating the anisotropic analysis of Baryon Acoustic Oscillation (BAO) scale in the CMASS and LOWZ galaxy samples ... More

Distance Priors from \emph{Planck} 2015 dataSep 03 2015Dec 18 2015We update the distance priors by adopting $Planck~ \textrm{TT,TE,EE}+\textrm{lowP}$ data released in 2015, and our results impose at least $30\%$ tighter constraints than those from $Planck~ \textrm{TT}+\textrm{lowP}$. Combining the distance priors with ... More

Distance Priors from Planck Final ReleaseAug 17 2018We present the distance priors from the finally released $Planck~ \textrm{TT,TE,EE}+\textrm{lowE}$ data in 2018. The uncertainties are around $40\%$ smaller than those from $Planck$ 2015 TT$+$lowP. In order to check the validity of these new distance ... More

Inflation model constraints from data released in 2015Dec 24 2015May 03 2016We provide the latest constraints on the power spectra of both scalar and tensor perturbations from the CMB data (including \textit{Planck}~2015, BICEP2 \& \textit{Keck Array} experiments) and the new BAO scales from SDSS-III BOSS observation. We find ... More

Combating the Control Signal Spoofing Attack in UAV SystemsApr 18 2018Unmanned aerial vehicle (UAV) system is vulnerable to the control signal spoofing attack due to the openness of the wireless communications. In this correspondence, a physical layer approach is proposed to combat the control signal spoofing attack, i.e,. ... More

Total Variation in Hamiltonian Formalism and Symplectic-Energy integratorsNov 21 2001We present a discrete total variation calculus in Hamiltonian formalism in this paper. Using this discrete variation calculus and generating functions for the flows of Hamiltonian systems, we derive two-step symplectic-energy integrators of any finite ... More

Difference Discrete Connection and Curvature on Cubic LatticeJul 25 2007In a way similar to the continuous case formally, we define in different but equivalent manners the difference discrete connection and curvature on discrete vector bundle over the regular lattice as base space. We deal with the difference operators as ... More

Total Variation and Variational Symplectic-Energy-Momentum integratorsSep 23 2001A discrete total variation calculus with variable time steps is presented in this letter. Using this discrete variation calculus, we generalize Lee's discrete mechanics and derive variational symplectic-energy-momentum integrators by Kane, Marsden and ... More

Fermion Localization and Degenerate Resonances on Brane ArrayJan 31 2019In this work, we consider the multi-wall braneworld arisen from multi-scalar fields, and investigate the localization and resonances of spin-1/2 fermion on the multi-walls. We build two analytic multi-wall solutions with a polynomial superpotential and ... More

A Gauge Field Model On $SU(2)_L\times SU(2)_R\times U(1)_Y \times π_4(G_{YM})$Oct 24 1994We reconstruct the Lagrangian of a left-right symmetric model with the gauge group $SU(2)_L\times SU(2)_R\times U(1)_Y \times \pi_4(SU(2)_L\times SU(2)_R\times U(1)_Y) $. The Higgs fields appear as gauge fields on discrete gauge group $\pi_4(SU(2)_L\times ... More

The Euler-Lagrange Cohomology and General Volume-Preserving SystemsApr 08 2003Apr 08 2003We briefly introduce the conception on Euler-Lagrange cohomology groups on a symplectic manifold $(\mathcal{M}^{2n}, \omega)$ and systematically present the general form of volume-preserving equations on the manifold from the cohomological point of view. ... More

Identifying the Fake Base Station: A Location Based ApproachJun 14 2018Fake base station (FBS) attack is a great security challenge to wireless user equipment (UE). During the cell selection stage, the UE receives multiple synchronization signals (SSs) from multiple nearby base stations (BSs), and then synchronizes itself ... More

A comprehensive comparison of cosmological models from latest observational dataJul 25 2012We investigate in detail some popular cosmological models in light of the latest observational data, including the Union2.1 supernovae compilation, the baryon acoustic oscillation measurements from the WiggleZ Dark Energy Survey, the cosmic microwave ... More

New cosmological constraints with extended-Baryon Oscillation Spectroscopic Survey DR14 quasar sampleJul 10 2017Oct 09 2017We update the constraints on the cosmological parameters by adopting the Planck data released in 2015 and Baryon Acoustic Oscillation (BAO) measurements including the new DR14 quasar sample measurement at redshift $z=1.52$, and we conclude that the based ... More

Constraint on the abundance of primordial black holes in dark matter from Planck dataAug 07 2016Dec 18 2016We use Planck data released in 2015 to constrain the abundance of primordial black holes (PBHs) in dark matter in two different reionization models (one is the instantaneous reionization and the other is the asymmetric reionization), and significantly ... More

A Large Family of Multi-path Dual Congestion Control AlgorithmsApr 19 2011The goal of traffic management is efficiently utilizing network resources via adapting of source sending rates and routes selection. Traditionally, this problem is formulated into a utilization maximization problem. The single-path routing scheme fails ... More

Plagiarism Detection using ROUGE and WordNetMar 22 2010With the arrival of digital era and Internet, the lack of information control provides an incentive for people to freely use any content available to them. Plagiarism occurs when users fail to credit the original owner for the content referred to, and ... More

The Euler-Lagrange Cohomology Groups on Symplectic ManifoldsApr 20 2003The definition and properties of the Euler-Lagrange cohomology groups $H^{2k-1}$, $1 \leqslant k \leqslant n$, on a symplectic manifold $({\cal M}^{2n},\omega)$ are given and studied. For $k = 1$ and $k = n$, they are isomorphic to the corresponding de ... More

Discrete mechanics Based on Finite Element MethodsMar 04 2002Discrete Mechanics based on finite element methods is presented in this paper. We also explore the relationship between this discrete mechanics and Veselov discrete mechanics. High order discretizations are constructed in terms of high order interpolations. ... More

Angular momentum transfer torques in spin valves with perpendicular magnetizationSep 28 2011Spin valves incorporating perpendicularly magnetized materials are promising structures for memory elements and high-frequency generators. We report the angular dependence of the spin-transfer torque in spin valves with perpendicular equilibrium magnetization ... More

Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. VI. Velocity-resolved Reverberation Mapping of H$β$ LineFeb 05 2016In the sixth of the series of papers reporting on a large reverberation mapping (RM) campaign of active galactic nuclei (AGNs) with high accretion rates, we present velocity-resolved time lags of H$\beta$ emission lines for nine objects observed in the ... More

A High-Quality velocity-delay map of the broad-line region in NGC 5548Sep 15 2018Sep 18 2018NGC 5548 has been well spectroscopically monitored for reverberation mapping of the central kinematics by 19 campaigns. Using the maximum entropy method in this Letter, we build up a high-quality velocity-delay map of the H$\beta$ emission line in the ... More

Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. IX 10 New Observations of Reverberation Mapping and Shortened H$β$ LagsFeb 08 2018As one of the series of papers reporting on a large reverberation mapping campaign of super-Eddington accreting massive black holes (SEAMBHs) in active galactic nuclei (AGNs), we present the results of 10 SEAMBHs monitored spectroscopically during 2015-2017. ... 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

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

Reverberation Mapping of the Broad-line Region in NGC 5548: Evidence for Radiation Pressure?Jul 27 2016NGC 5548 is the best-observed reverberation-mapped active galactic nucleus with long-term, intensive monitoring. Here we report results from a new observational campaign between January and July, 2015. We measure the centroid time lag of the broad H$\beta$ ... More

Supermassive black holes with high accretion rates in active galactic nuclei. VII. Reconstruction of velocity-delay maps by maximum entropy methodAug 02 2018As one of the series of papers reporting on a large reverberation mapping campaign, we apply the maximum entropy method (MEM) to 9 narrow-line Seyfert 1 galaxies with super-Eddington accretion rates observed during 2012-2013 for the velocity-delay maps ... More

Supermassive black holes with high accretion rates in active galactic nuclei: X. Optical variability characteristicsApr 06 2019We compiled a sample of 73 active galactic nuclei (AGNs) with reverberation mapping (RM) observations from RM campaigns including our ongoing campaign of monitoring super-Eddington accreting massive black holes (SEAMBHs). This sample covers a large range ... 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

Kinematics of the Broad-line Region of 3C 273 from a Ten-year Reverberation Mapping CampaignNov 09 2018Mar 13 2019Despite many decades of study, the kinematics of the broad-line region of 3C~273 are still poorly understood. We report a new, high signal-to-noise, reverberation mapping campaign carried out from November 2008 to March 2018 that allows the determination ... More

Lepton-Flavored Electroweak BaryogenesisSep 30 2016We explore lepton-flavored electroweak baryogenesis, driven by CP-violation in leptonic Yukawa sector, using the $\tau-\mu$ system in the two Higgs doublet model as an example. This setup generically yields, together with the flavor-changing decay $h\to ... More

A new single-dynamical-scalar-field model of dark energyAug 06 2005A new single-dynamical-scalar-field model of dark energy is proposed, in which either higher derivative terms nor structures of extra dimension are needed. With the help of a fixed background vector field, the parameter for the effective equation of state ... More

Evaluation of Treatment Effect Modification by Biomarkers Measured Pre- and Post-randomization in the Presence of Non-monotone MissingnessOct 26 2017In vaccine studies, investigators are often interested in studying effect modifiers of clinical treatment efficacy by biomarker-based principal strata, which is useful for selecting biomarker study endpoints for evaluating treatments in new trials, exploring ... More

Global Strong Solutions to Compressible Navier-Stokes System with Degenerate Heat Conductivity and Density-Depending ViscositySep 05 2018We consider the compressible Navier-Stokes system where the viscosity depends on density and the heat conductivity is proportional to a positive power of the temperature under stress-free and thermally insulated boundary conditions. Under the same conditions ... More

A New Kind of Uniformly Accelerated Reference FramesApr 04 2006A new kind of uniformly accelerated reference frames with a line-element different from the M{\o}ller and Rindler ones is presented, in which every observer at $x, y, z=$consts. has the same constant acceleration. The laws of mechanics are checked in ... More

Competitive Charging Station Pricing for Plug-in Electric VehiclesNov 24 2015Nov 28 2015This paper considers the problem of charging station pricing and plug-in electric vehicles (PEVs) station selection. When a PEV needs to be charged, it selects a charging station by considering the charging prices, waiting times, and travel distances. ... More

Global Strong Solutions to Magnetohydrodynamics with Density-Dependent Viscosity and Degenerate Heat-ConductivitySep 11 2018We deal with the equations of a planar magnetohydrodynamic compressible flow with the viscosity depending on the specific volume of the gas and the heat conductivity proportional to a positive power of the temperature. Under the same conditions on the ... More

Parallel energy-stable phase field crystal simulations based on domain decomposition methodsMar 03 2017In this paper, we present a parallel numerical algorithm for solving the phase field crystal equation. In the algorithm, a semi-implicit finite difference scheme is derived based on the discrete variational derivative method. Theoretical analysis is provided ... More

Optimization Design of Decentralized Control for Complex Decentralized SystemsSep 03 2018A new method is developed to deal with the problem that a complex decentralized control system needs to keep centralized control performance. The systematic procedure emphasizes quickly finding the decentralized subcontrollers that matching the closed-loop ... More

Long-distance continuous-variable quantum key distribution using separable Gaussian statesDec 04 2018Continuous-variable quantum key distribution (CVQKD) is considered to be an alternative to classical cryptography for secure communication. However, its transmission distance is restricted to metropolitan areas, given that it is affected by the channel ... More

Electromagnetic cloaking by layered structure of homogeneous isotropic materialsSep 04 2007Electromagnetic invisibility cloak requires material with anisotropic distribution of the constitutive parameters deduced from a geometrical transformation as first proposed by Pendry et al. [Science 312, 1780 (2006)]. In this paper, we proposed a useful ... More

Review of the Structural Stability, Electronic and Magnetic Properties of Nonmetal-Doped TiO$_2$ from First-Principles CalculationsFeb 25 2012This paper reviews and summarizes the recent first-principles theoretical studies of the structural stability, electronic structure, optical and magnetic properties of nonmetal-doped TiO$_2$. The first section presents a comparison study of the structural ... More

First-principles characterization of ferromagnetism in N-doped SrTiO3 and BaTiO3Oct 10 2011Jan 27 2012The spin-polarization and magnetic coupling character of N-doped SrTiO3 and BaTiO3 are studied through first-principles calculations. The substitutional N doping at O sites leads to a half-metallic property and produces a magnetic moment of 1.0 {\mu}B. ... More

MAPEL: Achieving Global Optimality for a Non-convex Wireless Power Control ProblemMay 17 2008Jun 10 2008Achieving weighted throughput maximization (WTM) through power control has been a long standing open problem in interference-limited wireless networks. The complicated coupling between the mutual interferences of links gives rise to a non-convex optimization ... More

Linear-Quadratic-Gaussian Mixed Mean-field Games with Heterogeneous Input ConstraintsOct 09 2017We consider a class of linear-quadratic-Gaussian mean-field games with a major agent and considerable heterogeneous minor agents in the presence of mean-field interactions. The individual admissible controls are constrained in closed convex subsets $\Gamma_{k}$ ... More

Linear Quadratic Mean Field Game with Control Input ConstraintOct 19 2016In this paper, we study a class of linear-quadratic (LQ) mean-field games in which the individual control process is constrained in a closed convex subset $\Gamma$ of full space $\mathbb{R}^m$. The decentralized strategies and consistency condition are ... More

Mandarin tone modeling using recurrent neural networksNov 06 2017We propose an Encoder-Classifier framework to model the Mandarin tones using recurrent neural networks (RNN). In this framework, extracted frames of features for tone classification are fed in to the RNN and casted into a fixed dimensional vector (tone ... More

Test for Incremental Value of New Biomarkers Based on OR RulesApr 24 2018In early detection of disease, a single biomarker often has inadequate classification performance, making it important to identify new biomarkers to combine with the existing marker for improved performance. A biologically natural method to combine biomarkers ... More

Logistic regression analysis with standardized markersNov 28 2013Two different approaches to analysis of data from diagnostic biomarker studies are commonly employed. Logistic regression is used to fit models for probability of disease given marker values, while ROC curves and risk distributions are used to evaluate ... More

Dynamic Partial Cooperative MIMO System for Delay-Sensitive Applications with Limited Backhaul CapacityJul 09 2013Considering backhaul consumption in practical systems, it may not be the best choice to engage all the time in full cooperative MIMO for interference mitigation. In this paper, we propose a novel downlink partial cooperative MIMO (Pco-MIMO) physical layer ... More

Long-distance continuous-variable quantum key distribution using non-Gaussian state-discrimination detectionAug 14 2017We propose a long-distance continuous-variable quantum key distribution (CVQKD) with four-state protocol using non-Gaussian state-discrimination detection. A photon subtraction operation, which is deployed at the transmitter, is used for splitting the ... More

Generalized massive gravity in arbitrary dimensions and its Hamiltonian formulationJun 20 2013Aug 27 2013We extend the four-dimensional de Rham-Gabadadze-Tolley (dRGT) massive gravity model to a general scalar massive-tensor theory in arbitrary dimensions, coupling a dRGT massive graviton to multiple scalars and allowing for generic kinetic and mass matrix ... More

Pilot Spoofing Attack by Multiple EavesdroppersJul 24 2018In this paper, we investigate the design of a pilot spoofing attack (PSA) carried out by multiple single-antenna eavesdroppers (Eves) in a downlink time-division duplex (TDD) system, where a multiple antenna base station (BS) transmits confidential information ... More

Numerical analysis of the production of $D^{(*)}(3000)$, $D_{sJ}(3040)$ and their partners through the semileptonic decays of $B_{(s)}$ mesons in terms of the light-front quark modelJun 23 2014Nov 03 2014Inspired by the newly observed $D^{(*)}(3000)$, and $D_{sJ}(3040)$ states, in this work we study the production of $D^{(*)}(3000)$, $D_{sJ}(3040)$ and their partners through the semileptonic decays of $B_{(s)}$ mesons, where the light-front Quark model ... More

Electron Transport Through Molecules: Gate Induced Polarization and Potential ShiftJun 25 2004We analyze the effect of a gate on the conductance of molecules by separately evaluating the gate-induced polarization and the potential shift of the molecule relative to the leads. The calculations use ab initio density functional theory combined with ... More

Molecular Conductance: Chemical Trends of Anchoring GroupsFeb 16 2004Sep 21 2004Combining density functional theory calculations for molecular electronic structure with a Green function method for electron transport, we calculate from first principles the molecular conductance of benzene connected to two Au leads through different ... More

Intermolecular Effect in Molecular ElectronicsSep 20 2004We investigate the effects of lateral interactions on the conductance of two molecules connected in parallel to semi-infinite leads. The method we use combines a Green function approach to quantum transport with density functional theory for the electronic ... More

Achieving Heisenberg-limited metrology with spin cat states via interaction-based readoutApr 11 2018Jul 18 2018Spin cat states are promising candidates for quantum-enhanced measurement. Here, we analytically show that the ultimate measurement precision of spin cat states approaches the Heisenberg limit, where the uncertainty is inversely proportional to the total ... More

Joint Spatial Division and Diversity for Massive MIMO SystemsSep 11 2018We propose a downlink beamforming scheme that combines spatial division and orthogonal space-time block coding (OSTBC) in multi-user massive MIMO systems. The beamformer is divided into two parts: a pre-beamforming matrix to separate the users into different ... More

Thermal convection with mixed thermal boundary conditions: Effects of insulating lids at the topFeb 14 2017Feb 16 2017The effects of insulating lids on the convection beneath were investigated experimentally using rectangular convection cells in the flux Rayleigh number range $2.3\times10^{9}\leq Ra_F \leq 1.8\times10^{11}$ and cylindrical cells in the range $1.4\times10^{10}\leq ... More

Base Station Cooperation in Millimeter Wave Cellular Networks: Performance Enhancement of Cell-Edge UsersJun 14 2018Millimeter wave (mmWave) signals are much more sensitive to blockage, which results in a significant increase of the outage probability, especially for the users at the edge of the cells. In this paper, we exploit the technique of base station (BS) cooperation ... More

Supermassive Black Hole Masses in Type II Active Galactic Nuclei with Polarimetric Broad Emission LinesJun 16 2008Type II AGNs with polarimetric broad emission line provided strong evidence for the orientation-based unified model for AGNs. We want to investigate whether the polarimetric broad emission line in type II AGNs can be used to calculate their central supermassive ... More

Dissipative Quantum Metrology with Spin Cat StatesOct 23 2014Oct 28 2014The maximally entangled states are excellent candidates for achieving Heisenberg-limited measurements in ideal quantum metrology, however, they are fragile against dissipation such as particle losses and their achievable precisions may become even worse ... More

Symmetry-Protected Quantum Adiabatic Evolution in Spontaneous Symmetry-Breaking TransitionsOct 13 2018Jan 23 2019Quantum adiabatic evolution, an important fundamental concept in physics, describes the dynamical evolution arbitrarily close to the instantaneous eigenstate of a slowly driven Hamiltonian. In most systems undergoing spontaneous symmetry-breaking transitions, ... More

The Role of the Exchange-Correlation Potential in ab initio Electron Transport CalculationsSep 25 2006Aug 23 2009The effect of the exchange-correlation potential in ab initio electron transport calculations is investigated by constructing optimized effective potentials (OEP) using different energy functionals or the electron density from second-order perturbation ... More

Models of Electrodes and Contacts in Molecular ElectronicsApr 04 2005Sep 08 2006Bridging the difference in atomic structure between experiments and theoretical calculations and exploring quantum confinement effects in thin electrodes (leads) are both important issues in molecular electronics. To address these issues, we report here, ... More

Non-Hermitian-assisted enhancement precision of parameter estimationSep 14 2016Recently, Zhong et al. [Phys. Rev. A 87, 022337(2013)] investigated the dynamics of quantum Fisher information (QFI) in the presence of decoherence. We here reform their results and propose two schemes to enhance and preserve the QFIs for a qubit system ... More

Non-Hermitian-assisted enhancement precision of parameter estimationSep 14 2016Oct 27 2016Recently, Zhong et al. [Phys. Rev. A 87, 022337(2013)] investigated the dynamics of quantum Fisher information (QFI) in the presence of decoherence. We here reform their results and propose two schemes to enhance and preserve the QFIs for a qubit system ... More

Time-Dependent Transport Through Molecular JunctionsFeb 07 2010We investigate transport properties of molecular junctions under two types of bias--a short time pulse or an AC bias--by combining a solution for the Green functions in the time domain with electronic structure information coming from ab initio density ... More

Efficient Processing of Reachability and Time-Based Path Queries in a Temporal GraphJan 22 2016Jan 25 2016A temporal graph is a graph in which vertices communicate with each other at specific time, e.g., $A$ calls $B$ at 11 a.m. and talks for 7 minutes, which is modeled by an edge from $A$ to $B$ with starting time "11 a.m." and duration "7 mins". Temporal ... More

Ultrafast modulation of near-field heat transfer with tunable metamaterialsDec 26 2012We propose a mechanism of active near-field heat transfer modulation relying on externally tunable metamaterials. A large modulation effect is observed and can be explained by the coupling of surface modes, which is dramatically varied in the presence ... More

Multiple Antennas Secure Transmission under Pilot Spoofing and Jamming AttackJan 12 2018Transmitter-side channel state information (CSI) of the legitimate destination plays a critical role in physical layer secure transmissions. However, channel training procedure is vulnerable to the pilot spoofing attack (PSA) or pilot jamming attack (PJA) ... More

Distillability sudden death and sudden birth in a two-qutrit system under decoherence of finite temperatureJun 09 2015Jun 22 2015Distillability sudden death and sudden birth in a two-qutrit system under decoherence of finite temperature is studied in detail. By using of the negativity and realignment criterion, it is shown that certain initial prepared free entangled states may ... More

Highly (111)-orientated BiFeO3 thin film deposited on La0.67Sr0.33MnO3 buffered Pt/TiO2/SiO2/Si (100) substrateMar 02 2012Multiferroic BiFeO3 (BFO) thin film exhibiting desired ferroelectric and enhanced magnetic properties was grown on La0.67Sr0.33MnO3 (LSMO) buffered Pt/TiO2/SiO2/Si substrates by off-axis RF magnetic sputtering, where a highly (111)-oriented texture was ... More

Quantum Interference Controlled Molecular ElectronicsJun 22 2008Aug 10 2009Quantum interference in coherent transport through single molecular rings may provide a mechanism to control current in molecular electronics. We investigate its applicability by using a single-particle Green function method combined with ab initio electronic ... More

Addition Energies of Fullerenes and Nanotubes as Quantum Dots: The Role of SymmetryJan 13 2003May 11 2004Using density-functional theory calculations, we investigate the addition energy (AE) of quantum dots formed of fullerenes or closed single-wall carbon nanotubes. We focus on the connection between symmetry and oscillations in the AE spectrum. In the ... More

Electron transport through single conjugated organic molecules: Basis set effects in ab initio calculationsMay 23 2007We investigate electron transport through single conjugated molecules - including benzenedithiol, oligo-phenylene-ethynylenes of different lengths, and a ferrocene-containing molecule sandwiched between two gold electrodes with different contact structures ... More

Nanotube-Metal Junctions: 2- and 3- Terminal Electrical TransportNov 22 2005Sep 14 2006We address the quality of electrical contact between carbon nanotubes and metallic electrodes by performing first-principles calculations for the electron transmission through ideal 2- and 3-terminal junctions, thus revealing the physical limit of tube-metal ... More

Compact gravimeter with an ensemble of ultracold atoms in spin-dependent optical latticesApr 27 2018Oct 28 2018Atomic interferometry in optical lattices is a new trend of developing practical quantum gravimeter. Here, we propose a compact and portable gravimetry scheme with an ensemble of ultracold atoms in gravitationally tilted spin-dependent optical lattices. ... More