Results for "Fengqing Zhu"

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Texture Segmentation Based Video Compression Using Convolutional Neural NetworksFeb 08 2018There has been a growing interest in using different approaches to improve the coding efficiency of modern video codec in recent years as demand for web-based video consumption increases. In this paper, we propose a model-based approach that uses texture ... More
A Wong-Zakai theorem for $Φ^4_3$ modelApr 16 2015We prove a version of the Wong-Zakai theorem for the dynamical $\Phi_3^4$ model driven by space-time white noise on $\mathbb{T}^3$. For the $\Phi^4_3$ model it is proved in [Hai14] that a renormalisation has to be performed in order to define the nonlinear ... More
Random attractor associated with the quasi-geostrophic equationMar 24 2013We study the long time behavior of the solutions to the 2D stochastic quasi-geostrophic equation on $\mathbb{T}^2$ driven by additive noise and real linear multiplicative noise in the subcritical case (i.e. $\alpha>1/2$) by proving the existence of a ... More
Dimension reduction-based significance testing in nonparametric regressionOct 13 2015A dimension reduction-based adaptive-to-model test is proposed for significance of a subset of covariates in the context of a nonparametric regression model. Unlike existing local smoothing significance tests, the new test behaves like a local smoothing ... More
Lattice approximation to the dynamical $Φ_3^4$ modelAug 23 2015We study the lattice approximations to the dynamical $\Phi^4_3$ model by paracontrolled distributions proposed in [GIP13]. We prove that the solutions to the lattice systems converge to the solution to the dynamical $\Phi_3^4$ model in probability, locally ... More
Approximating three-dimensional Navier-Stokes equations driven by space-time white noiseSep 17 2014In this paper we study approximations to 3D Navier-Stokes (NS) equation driven by space-time white noise by paracontrolled distribution proposed in [GIP13]. A solution theory for this equation has been developed recently in [ZZ14] based on regularity ... More
Three-dimensional Navier-Stokes equations driven by space-time white noiseMay 31 2014Jun 10 2015In this paper we study 3D Navier-Stokes (NS) equation driven by space-time white noise by using regularity structure theory introduced in [Hai14] and paracontrolled distribution proposed in [GIP13]. We obtain local existence and uniqueness of solutions ... More
A Generalization of the Kodaira Vanishing and Embedding TheoremFeb 02 1995We give several generalizations of the Kodaira vanishing and embedding theorems for K\"ahler manifolds to the case where the relevent line bundle has a small region of negative curvature. To prove the vanishing theorems we adapt techniques of Elworthy-Rosenberg ... More
Spectra and elliptic flow of (multi-)strange hadrons at RHIC and LHC within viscous hydrodynamics+hadron cascade hybrid modelJul 14 2016Aug 15 2016Using the (2+1)-dimensional ultrarelativistic viscous hydrodynamics+hadron cascade, VISHNU, hybrid model, we study the $p_{\rm T}$-spectra and elliptic flow of $\Lambda$, $\Xi$, and $\Omega$ in Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV and in Pb+Pb ... More
Log rationally connected surfacesDec 08 2014Jul 02 2015In this paper, combining the works of Miyanishi-Tsunoda and Keel-McKernan, we prove the log Castelnuovo's rationality criterion for smooth quasiprojective surfaces over complex numbers.
The second variation of the Ricci expander entropyJan 19 2009We compute the second variation of the Ricci expander entropy and briefly discuss the linear stability of compact negative Einstein manifolds.
Harmonic maps from degenerating Riemann surfacesMar 25 2008We study harmonic maps from degenerating Riemann surfaces with uniformly bounded energy and show the so-called generalized energy identity. We find conditions that are both necessary and sufficient for the compactness in $W^{1,2}$ and $C^{0}$ modulo bubbles ... More
On the semi-regular module and vertex operator algebrasNov 20 2007Dec 03 2007We prove a conjecture stated in a previous paper by the author about the existence of canonical filtrations for a family of vertex operator algebras in rational levels.
Some inequalities related to isoperimetric inequalities with partial free boundaryJan 09 2001Feb 16 2001The main purpose of this paper is to prove a sharp Sobolev inequality in an exterior of a convex bounded domain. There are two ingredients in the proof: One is the observation of some new isoperimetric inequalities with partial free boundary, and the ... More
When is the majority-vote classifier beneficial?Jul 24 2013In his seminal work, Schapire (1990) proved that weak classifiers could be improved to achieve arbitrarily high accuracy, but he never implied that a simple majority-vote mechanism could always do the trick. By comparing the asymptotic misclassification ... More
Kernels and Ensembles: Perspectives on Statistical LearningDec 06 2007Since their emergence in the 1990's, the support vector machine and the AdaBoost algorithm have spawned a wave of research in statistical machine learning. Much of this new research falls into one of two broad categories: kernel methods and ensemble methods. ... More
Vertex operator algebras associated to modified regular representations of affine Lie algebrasNov 17 2006Nov 20 2007Let $G$ be a simple complex Lie group with Lie algebra $\mf g$ and let $\af$ be the affine Lie algebra. We use intertwining operators and Knizhnik-Zamolodchikov equations to construct a family of $\N$-graded vertex operator algebras associated to $\mf ... More
An axiomatic approach to the roughness measure of rough setsNov 28 2009May 25 2010In Pawlak's rough set theory, a set is approximated by a pair of lower and upper approximations. To measure numerically the roughness of an approximation, Pawlak introduced a quantitative measure of roughness by using the ratio of the cardinalities of ... More
Covering rough sets based on neighborhoods: An approach without using neighborhoodsNov 28 2009Dec 10 2010Rough set theory, a mathematical tool to deal with inexact or uncertain knowledge in information systems, has originally described the indiscernibility of elements by equivalence relations. Covering rough sets are a natural extension of classical rough ... More
Dirac-harmonic maps from degenerating spin surfaces I: the Neveu-Schwarz caseMar 26 2008We study Dirac-harmonic maps from degenerating spin surfaces with uniformly bounded energy and show the so-called generalized energy identity in the case that the domain converges to a spin surface with only Neveu-Schwarz type nodes. We find condition ... More
Explicit Maximum Likelihood Loss Estimator in Multicast TomographyApr 27 2010For the tree topology, previous studies show the maximum likelihood estimate (MLE) of a link/path takes a polynomial form with a degree that is one less than the number of descendants connected to the link/path. Since then, the main concern is focused ... More
A regularity theory for multiple-valued Dirichlet minimizing mapsAug 07 2006This paper discusses the regularity of multiple-valued Dirichlet minimizing maps into the sphere. It shows that even at branched point, as long as the normalized energy is small enough, we have the energy decay estimate. Combined with the previous work ... More
A geometrizing higher twist effect on nuclear targetAug 30 2004Feb 13 2005The higher twist effects in deep inelastic scattering on the nuclear target are studied using time ordered perturbation theory. We showed that the collinear rescattering of the outgoing quark on the extra nucleons via the contacting gluon-pair is dominant ... More
A scattering matrix approach to quantum pumping: Beyond the small-ac-driving-amplitude limitNov 06 2009In the adiabatic and weak-modulation quantum pump, net electron flow is driven from one reservoir to the other by absorbing or emitting an energy quantum $\hbar \omega $ from or to the reservoirs. In our approach, high-order dependence of the scattering ... More
Exotic Charmonium-like States at BESIIIMay 18 2015The recent measurement results of exotic charmonium-like states, the so called XYZ particles, at BESIII have been presented. I mainly discussed the charged Zc(3900) state, its neutral partner, and possible excited states.
Charmonium and Light Meson SpectroscopyDec 10 2012This talk reviews recent experimental results on selected topics in the spectroscopy of charmonia, charmonium-like states and light mesons.
A New View of Classification in Astronomy with the Archetype Technique: An Astronomical Case of the NP-complete Set Cover ProblemJun 23 2016We introduce a new generic Archetype technique for source classification and identification, based on the NP-complete set cover problem (SCP) in computer science and operations research (OR). We have developed a new heuristic SCP solver, by combining ... More
The Lp Minkowski problem for polytopes for negative pFeb 25 2016May 07 2016Existence of solutions to the Lp Minkowski problem is proved for all p less than 0. For the cirtical case of p=-n, which is known as the centro-affine Minkowski problem, this paper contains the main result in [71] as a special case.
Deformations of glassy polymers in very low temperature regime within cylindrical microporesAug 28 2008Apr 09 2009The deformation kinetics for glassy polymers confined in microscopic domain at very low temperature regime was investigated using a transition-rate-state dependent model considering the shear thinning behavior which means, once material being subjected ... More
WIMPless dark matter and the excess gamma rays from the Galactic centerJan 23 2011Apr 05 2011In this paper we discuss the excess gamma rays from the Galactic center, the WMAP haze and the CoGeNT and DAMA results in WIMPless models. At the same time we also investigate the low energy constraints from the anomalous magnetic moment of leptons and ... More
Some sufficient conditions on Hamiltonian digraphDec 23 2008Z-mapping graph is a balanced bipartite graph $G$ of a digraph $D$ by split each vertex of $D$ into a pair of vertices of $G$. Based on the property of the $G$, it is proved that if $D$ is strong connected and $G$ is Hamiltonian, then $D$ is Hamiltonian. ... More
The Complexity of Determining Existence a Hamiltonian Cycle is $O(n^3)$Jun 19 2007The Hamiltonian cycle problem in digraph is mapped into a matching cover bipartite graph. Based on this mapping, it is proved that determining existence a Hamiltonian cycle in graph is $O(n^3)$.
Generalized cluster complexes via quiver representationsJul 06 2006May 23 2007We give a quiver representation theoretic interpretation of generalized cluster complexes defined by Fomin and Reading. By using $d-$cluster categories which are defined by Keller as triangulated orbit categories of (bounded) derived categories of representations ... More
Equivalences between cluster categoriesNov 15 2005Jun 19 2006Tilting theory in cluster categories of hereditary algebras has been developed in [BMRRT] and [BMR]. These results are generalized to cluster categories of hereditary abelian categories. Furthermore, for any tilting object $T$ in a hereditary abelian ... More
BGP-reflection functors and cluster combinatoricsNov 15 2005Jul 14 2006We define Bernstein-Gelfand-Ponomarev reflection functors in the cluster categories of hereditary algebras. They are triangle equivalences which provide a natural quiver realization of the "truncated simple reflections" on the set of almost positive roots ... More
Applications of BGP-reflection functors: isomorphisms of cluster algebrasNov 15 2005Jun 19 2006Given a symmetrizable generalized Cartan matrix $A$, for any index $k$, one can define an automorphism associated with $A,$ of the field $\mathbf{Q}(u_1, >..., u_n)$ of rational functions of $n$ independent indeterminates $u_1,..., u_n.$ It is an isomorphism ... More
Nonlinear Model Reduction Based On The Finite Element Method With Interpolated Coefficients: Semilinear Parabolic EquationsApr 01 2013Apr 28 2013For nonlinear reduced-order models, especially for those with non-polynomial nonlinearities, the computational complexity still depends on the dimension of the original dynamical system. As a result, the reduced-order model loses its computational efficiency, ... More
On the comparison theorem for multidimensional SDEs with jumpsJun 08 2010In this note, we give a necessary and sufficient condition under which the comparison theorem holds for multidimensional stochastic differential equations (SDEs) with jumps and for matrix-valued SDEs with jumps.
Spin-dependent electron grating effect from helical magnetization in multiferroic tunnel junctionsApr 27 2012In multiferroic oxides with a transverse helical magnetic order, the magnetization exchange coupling is sinusoidally space-dependent. We theoretically investigate the spin-dependent electron grating effect in normal-metal/helical-multiferroic/ferromagnettic ... More
Conductance in the Helimagnet- and Skyrmion-Lattice-Embedded Electron WaveguideNov 22 2013The helimagnet (HM) and skyrmion lattice (SL) are topologically nontrivial magnetic states. Their spin texture gives rise to finite topological magnetic field and Lorentz force. As a demonstration of the emergent electrodynamics besides the Hall effect, ... More
Integral Solutions to Linear Indeterminate EquationMar 08 2011In this paper, using Euler's function, we give a formula of all integral solutions to linear indeterminate equation with $s$-variables $a_1x_1+a_2x_2+...+a_sx_s=n$. It is a explicit formula of the coefficients $a_1$, $a_2$,..., $a_s$ and the free term ... More
n-Groupoids and Stacky GroupoidsJan 14 2008Jun 29 2009We discuss two generalizations of Lie groupoids. One consists of Lie $n$-groupoids defined as simplicial manifolds with trivial $\pi_{k\geq n+1}$. The other consists of stacky Lie groupoids $\cG\rra M$ with $\cG$ a differentiable stack. We build a 1-1 ... More
Lie n-groupoids and stacky Lie groupoidsSep 14 2006Nov 13 2006We discuss two sorts of generalization of Lie groupoids. One is Lie $n$-groupoids defined as simplicial manifolds with trivial $\pi_{k\geq n+1}$. The other is the stacky Lie groupoid $\cG\rra M$ with $\cG$ a differentiable stack. We build 1-1 correspondence ... More
Integrating Lie algebroids via stacks and applications to Jacobi manifoldsMay 09 2005Lie algebroids can not always be integrated into Lie groupoids. We introduce a new object--``Weinstein groupoid'', which is a differentiable stack with groupoid-like axioms. With it, we have solved the integration problem of Lie algebroids. It turns out ... More
The Morse index theorem for regular Lagrangian systemsSep 18 2001In this paper, we prove a Morse index theorem for the index form of regular Lagrangian system with selfadjoint boundary condition.
Ruin Probabilities for Risk Processes with Non-Stationary Arrivals and Subexponential ClaimsApr 06 2013Oct 14 2014In this paper, we obtain the finite-horizon and infinite-horizon ruin probability asymptotics for risk processes with claims of subexponential tails for non-stationary arrival processes that satisfy a large deviation principle. As a result, the arrival ... More
Optimal Strategies for a Long-Term Static InvestorNov 24 2013Oct 14 2014The optimal strategies for a long-term static investor are studied. Given a portfolio of a stock and a bond, we derive the optimal allocation of the capitols to maximize the expected long-term growth rate of a utility function of the wealth. When the ... More
The quantization for in-homogeneous self-similar measures with in-homogeneous open set conditionJul 05 2014Let $(g_i)_{i=1}^M$ be a family of contractive similitudes satisfying the open set condition. Let $\nu$ be a self-similar measure associated with $(g_i)_{i=1}^M$. We study the quantization problem for the in-homogeneous self-similar measure $\mu$ associated ... More
Information complementarity: A new paradigm for decoding quantum incompatibilityJun 26 2014Sep 14 2015The existence of observables that are incompatible or not jointly measurable is a characteristic feature of quantum mechanics, which lies at the root of a number of nonclassical phenomena, such as uncertainty relations, wave--particle dual behavior, Bell-inequality ... More
Nonexistence of sharply covariant mutually unbiased bases in odd prime dimensionsJun 18 2015Aug 23 2015Mutually unbiased bases (MUB) are useful in a number of research areas. The symmetry of MUB is an elusive and interesting subject. A (complete set of) MUB in dimension $d$ is sharply covariant if it can be generated by a group of order $d(d+1)$ from a ... More
Riesz transform characterization of weighted Hardy spaces associated to Schrödinger operatorsMay 21 2014In this paper, we characterize the weighted local Hardy spaces $h^p_\rho(\omega)$ related to the critical radius function $\rho$ and weights $\omega\in A_{1}^{\rho,\,\infty}(\mathbb{R}^{n})$ by localized Riesz transforms $\widehat{R}_j$, in addition, ... More
Jet schemes and singularities of W^r_d(C) lociDec 05 2012Kempf proved that the theta divisor of a smooth projective curve C has rational singularities. In this paper we estimate the dimensions of the jet schemes of the theta divisor and show that all these schemes are irreducible. In particular, we recover ... More
The higher order terms in asymptotic expansion of color Jones polynomialsApr 03 2011Color Jones polynomial is one of the most important quantum invariants in knot theory. Finding the geometric information from the color Jones polynomial is an interesting topic. In this paper, we study the general expansion of color Jones polynomial which ... More
Natural compactification of the moduli of toric pairs from the perspective of mirror symmetryOct 20 2014Sep 13 2016We construct a compactification of the moduli of toric pairs by using ideas from mirror symmetry. The secondary fan $\Sigma(Q)$ is used in [Ale02] to parametrize degenerations of toric pairs. It is also used in [CLS11] to control the variation of GIT. ... More
Towards a dictionary for the Bargmann transformJun 21 2015There is a canonical unitary transformation from $L^2(\R)$ onto the Fock space $F^2$, called the Bargmann transform. The purpose of this article is to translate some important results and operators from the context of $L^2(\R)$ to that of $F^2$. Examples ... More
Uncertainty principles for the Fock spaceJan 12 2015Several uncertainty principles are proved for the Fock space.
On a proof of the Bouchard-Sulkowski conjectureAug 14 2011In this short note, we give a proof of the free energy part of the BKMP conjecture of C^3 proposed by Bouchard and Sulkowski [4]. Hence the proof of the full BKMP conjecture for the case of C^3 has been finished.
The Laplace transform of the cut-and-join equation of Mariño-Vafa formula and its applicationsJan 05 2010By the same method introduced in [9], we calculate the Laplace transform of the celebrated cut-and-join equation of Mari\~no-Vafa formula discovered by C. Liu, K. Liu and J. Zhou [17]. Then, we study the applications of the polynomial identity (1) obtained ... More
The optimal control related to Riemannian manifolds and the viscosity solutions to H-J-B equationsJan 16 2010This paper is concerned with the Dynamic Programming Principle (DPP in short) with SDEs on Riemannian manifolds. Moreover, through the DPP, we conclude that the cost function is the unique viscosity solution to the related PDEs on manifolds.
On the gluing formula of real analytic torsion formsMay 13 2014In this paper we extend first the Bismut-Lott's analytic torsion form for flat vector bundles to the boundary case, then we establish its gluing formula on a smooth fibration under the assumption that a fiberwise Morse function exists. We assume that ... More
The RPC-based proposal for the ATLAS forward muon trigger upgrade in view of super-LHCOct 25 2012The innermost station of the present ATLAS forward muon detector needs to be upgraded for the super-LHC. We present a proposal to replace it with a sandwiched detector composed of several layers of small-radius Monitored Drift Tube chambers (sMDT) for ... More
An introduction to affine Grassmannians and the geometric Satake equivalenceMar 17 2016Apr 04 2016We introduce various affine Grassmannians, study their geometric properties, and give some applications. We also discuss the geometric Satake equivalence. These are the expanded lecture notes for a mini-course in 2015 PCMI summer school. References updated ... More
Study of an Equivalent Proposition of Riemann HypothesisSep 24 2016Let $H_n = \sum_{k = 1}^{n}\frac{1}{k}$. Using Chebyshev function and prime number theorem, this paper proves that, there exists a positive constant A, such that for all natural numbers $n = q_1 * q_2 *... * q_m$ or $n = q_1^{\alpha_1} * q_2^{\alpha_1} ... More
Low-intensity light switching of cavity-atom polaritonsFeb 03 2010Mar 22 2010I analyze an all-optical switching scheme in a cavity QED system consisting of multiple three-level atoms confined in a cavity mode. A control laser coupled to the atoms from free space induces quantum interference in the coupled cavity-atom system and ... More
Prescribing integral curvature equationJul 10 2014Feb 07 2015In this paper we formulate new curvature functions on $\mathbb{S}^n$ via integral operators. For certain even orders, these curvature functions are equivalent to the classic curvature functions defined via differential operators, but not for all even ... More
Regular representations of the quantum groups at roots of unityNov 20 2007Dec 03 2007We study the bimodule structure of the quantum function algebra at roots of 1 and prove that it admits an increasing filtration with factors isomorphic to the tensor products of the dual of Weyl modules $V_\lambda^* \otimes V_{- \omega_0 \lambda}^*$. ... More
Multiple list colouring of planar graphsMay 16 2016This paper proves that for each positive integer $m$, there is a planar graph $G$ which is not $(4m+\lfloor \frac{2m-1}{9}\rfloor,m)$-choosable. Then we pose some conjectures concerning multiple list colouring of planar graphs.
The order of the group of self-homotopy equivalence of wedge spacesAug 01 2015In this paper $Aut(\Sigma X\vee \Sigma Y)^\#$ the order of the group of self-homotopy equivalence of wedge spaces is studied. Under the condition of reducibility, we decompose $ Aut(\bigvee\limits_{t=1}^{k}X_{t})$ to the product of subgroups which generalizes ... More
On the Complexity of Protein Local Structure Alignment Under the Discrete Fréchet DistanceSep 05 2007We show that given $m$ proteins (or protein backbones, which are modeled as 3D polygonal chains each of length O(n)) the problem of protein local structure alignment under the discrete Fr\'{e}chet distance is as hard as Independent Set. So the problem ... More
Preprojective cluster variables of acyclic cluster algebrasNov 29 2005Aug 30 2006For any valued quiver, by using BGP-reflection functors, an injection from the set of preprojective objects in the cluster category to the set of cluster variables of the corresponding cluster algebra is given, the images are called preprojective cluster ... More
Speedup of Micromagnetic Simulations with C++ AMP On Graphics Processing UnitsJun 29 2014A finite-difference Micromagnetic solver is presented utilizing the C++ Accelerated Massive Parallelism (C++ AMP). The high speed performance of a single Graphics Processing Unit (GPU) is demonstrated compared to a typical CPU-based solver. The speed-up ... More
Accelerate micromagnetic simulations with GPU programming in MATLABJan 25 2015A finite-difference Micromagnetic simulation code written in MATLAB is presented with Graphics Processing Unit (GPU) acceleration. The high performance of Graphics Processing Unit (GPU) is demonstrated compared to a typical Central Processing Unit (CPU) ... More
BSDE and generalized Dirichlet forms: the infinite dimensional caseJan 16 2012We consider the following quasi-linear parabolic system of backward partial differential equations on a Banach space $E$: $(\partial_t+L)u+f(\cdot,\cdot,u, A^{1/2}\nabla u)=0$ on $[0,T]\times E,\qquad u_T=\phi$, where $L$ is a possibly degenerate second ... More
Projective dimension and regularity of the path ideal of the line graphOct 10 2016Oct 26 2016By generalizing the notion of the path ideal of a graph, we study some algebraic properties of some path ideals associated to a line graph. We show that the quotient ring of these ideals are always sequentially Cohen-Macaulay and also provide some exact ... More
The Lp Minkowski problem for polytopes for 0 < p < 1Jun 29 2014Aug 02 2014Necessary and sufficient conditions are given for the existence of solutions to the discrete Lp Minkowski problem for the critical case where 0 < p < 1.
Implications of the recent measurement of pure annihilation $B_s \to π^+ π^-$ decays in QCD factorizationJun 23 2011Jul 20 2011The CDF 3.7 sigma evidence of pure annihilation $B_s \to \pi^+ \pi^-$ decays, if confirmed, would imply a large annihilation scenario in the QCD factorization approach. This is somewhat unexpected as the large annihilation scenario was disfavored in previous ... More
B physics constraints on a flavor symmetric scalar model to account for the ttbar asymmetry and Wjj excess at CDFApr 16 2011Jul 22 2011Recently Nelson et al. proposed an interesting flavor symmetric model to account for the top quark forward-backward asymmetry and the dijet anomaly at CDF simultaneously with just three parameters: a coupling constant of order one, and two scalar masses ... More
The Complexity of HCP in Digraps with Degree Bound TwoApr 03 2007Jul 13 2007The Hamiltonian cycle problem (HCP) in digraphs D with degree bound two is solved by two mappings in this paper. The first bijection is between an incidence matrix C_{nm} of simple digraph and an incidence matrix F of balanced bipartite undirected graph ... More
Maximal zero sequences for Fock spacesOct 11 2011A sequence $Z$ in the complex plane $\C$ is called a zero sequence for the Fock space $F^p_\alpha$ if there exists a function $f\in F^p_\alpha$, not identically zero, such that $Z$ is the zero set of $f$, counting multiplicities. We show that there exist ... More
Large deviations for Markovian nonlinear Hawkes processesAug 11 2011Mar 17 2015Hawkes process is a class of simple point processes that is self-exciting and has clustering effect. The intensity of this point process depends on its entire past history. It has wide applications in finance, neuroscience and many other fields. In this ... More
The sharp lower bound for the volume of 3-folds of general type with χ(\Co{X})=1Oct 24 2007Let $V$ be a smooth projective 3-fold of general type. Denote by $K^{3}$, a rational number, the self-intersection of the canonical sheaf of any minimal model of $V$. One defines $K^{3}$ as a canonical volume of $V$. The paper is devoted to proving the ... More
Quasiprobability representations of quantum mechanics with minimal negativityApr 24 2016Aug 25 2016Quasiprobability representations, such as the Wigner function, play an important role in various research areas. The inevitable appearance of negativity in such representations is often regarded as a signature of nonclassicality, which has profound implications ... More
On general (alpha,beta)-metrics with vanishing Douglas curvatureMay 29 2015In this paper, we study a class of Finsler metrics called general $(\alpha,\beta)$-metrics, which are defined by a Riemannian metric $\alpha$ and a $1$-form $\beta$. We find an equation which is necessary and sufficient condition for such Finsler metric ... More
Permutation Symmetry Determines the Discrete Wigner FunctionApr 15 2015Jan 10 2016The Wigner function provides a useful quasiprobability representation of quantum mechanics, with applications in various branches of physics. Many nice properties of the Wigner function are intimately connected with the high symmetry of the underlying ... More
Multiqubit Clifford groups are unitary 3-designsOct 09 2015We show that the multiqubit (including qubit) Clifford group in any even prime power dimension is not only a unitary 2-design, but also a unitary 3-design. Moreover, it is a minimal unitary 3-design except for dimension 4. As an immediate consequence, ... More
On general $(α,β)$-metrics with isotropic Berwald curvatureJun 05 2015In this paper, we study a class of Finsler metrics called general $(\alpha,\beta)$-metrics, which are defined by a Riemannian metric $\alpha$ and a $1$-form $\beta$. We classify this class of Finsler metrics with isotropic Berwald curvature under certain ... More
Evidence of Different Formation Mechanisms for Hot versus Warm Super-EarthsMar 05 2015Using the Kepler planet sample from Buchhave et al. and the statistical method clarified by Schlaufman, I show that the shorter-period super-Earths have a different dependence on the host star metallicity from the longer-period super-Earths, with the ... More
An Energy Reducing Flow for Multiple-Valued FunctionsJun 20 2006By the method of discrete Morse flows, we construct an energy reducing multiple-valued function flow. The flow we get is Holder continuous with respect to the L-2 norm. We also give another way of constructing flows in some special cases, where the flow ... More
Loss Tomography in General TopologyMar 25 2016Although there are a few works reported in the literature considering loss tomography in the general topology, there is few well established result since all of them rely either on simulations or on experiments that have many random factors affecting ... More
Are valence quarks rotating?Oct 27 2012We suggest to compare the deep inelastic scattering structure functions measured in the unpolarized charged-lepton scattering off a transversely polarized proton and off a longitudinally polarized proton at larger Bjorken variable $x$, one may get a direct ... More
Application of Jet Trimming in Boosted Higgs SearchJul 09 2011We present the study of the $WH$ and $ZH$ search with the Higgs Boson decayed to $b\bar{b}$ at the Large Hadron Collider. The Higgs Boson and the Vector Boson are required to be boosted, and the Higgs Boson is reconstructed with Jet Trimming Technique. ... More
A Closed Form Maximum Likelihood Estimator to End-to-End Loss Rate EstimationApr 30 2011Oct 01 2012Loss tomography has been studied for more than 10 years and a number of estimators have been proposed. The estimators can be divided into two classes: maximum likelihood and non-maximum likelihood. The maximum likelihood estimators rely on the maximum ... More
Loss Rate Inference in Multi-Sources and Multicast-Based General TopologySep 14 2010Jul 20 2011Loss tomography has received considerable attention in recent years and a number of estimators have been proposed. Unfortunately, almost all of them are devoted to the tree topology despite the general topology is more common in practice. In addition, ... More
Lie II theorem for Lie algebroids via higher groupoidsDec 31 2006May 20 2010Following Sullivan's spacial realization of a differential algebra, we construct a universal integrating Lie 2-groupoid for every Lie algebroid. Then We show that unlike Lie algebras which one-to-one correspond to simply connected Lie groups, Lie algebroids ... More
A generalized Morse index theoremApr 07 2005In this paper, we prove a Morse index theorem for the index form of even order linear Hamiltonian systems on the closed interval with reasonable self-adjoint boundary conditions. The highest order term is assumed to be nondegenerate.
Diffraction induced Spin Pumping in Normal-Metal/Multiferroic-Helimagnet/Ferromagnet HeterostructuresMay 30 2014Generally the adiabatic quantum pumping phenomenon can be interpreted by the surface integral of the Berry curvature inside the cyclic loop. Spin angular momentum flow without charge current can be pumped out by magnetization precession in ferromagnet-based ... More
A note on the quantization error for in-homogeneous self-similar measuresAug 31 2016We further study the asymptotics of quantization errors for two classes of in-homogeneous self-similar measures $\mu$. We give a new sufficient condition for the upper quantization coefficient for $\mu$ to be finite. This, together with our previous work, ... More
Convergence order of the geometric mean errors for Markov-type measuresOct 26 2014We study the quantization problem with respect to the geometric mean error for Markov-type measures $\mu$ on a class of fractal sets. Assuming the irreducibility of the corresponding transition matrix $P$, we determine the exact convergence order of the ... More
Asymptotic order of the quantization errors for self-affine measures on Bedford-McMullen carpetsApr 19 2016Let $E$ be a Bedford-McMullen carpet determined by a set of affine mappings $(f_{ij})_{(i,j)\in G}$ and $\mu$ a self-affine measure on $E$ associated with a probability vector $(p_{ij})_{(i,j)\in G}$. We prove that, for every $r\in(0,\infty)$, the upper ... More
Regularity for harmonic maps into certain Pseudo-Riemannian manifoldsJan 10 2011Mar 20 2012In this article, we investigate the regularity for certain elliptic systems without a $L^2$-antisymmetric structure. As applications, we prove some $\epsilon$-regularity theorems for weakly harmonic maps from the unit ball $B= B(m) \subset \mathbb{R}^m ... More