Results for "Xin Kang"

total 10410took 0.14s
On the Severi type inequalities for irregular surfacesApr 24 2015Apr 27 2015Let $X$ be a minimal surface of general type and maximal Albanese dimension with irregularity $q\geq 2$. We show that $K_X^2\geq 4\chi(\mathcal O_X)+4(q-2)$ if $K_X^2<\frac92\chi(\mathcal O_X)$, and also obtain the characterization of the equality. As ... More
The Oort conjecture on Shimura curves in the Torelli locus of curvesMay 19 2014Aug 18 2014Oort has conjectured that there do not exist Shimura curves contained generically in the Torelli locus of genus-$g$ curves when $g$ is large enough. In this paper we prove the Oort conjecture for Shimura curves of Mumford type and Shimura curves parameterizing ... More
Incentive Mechanisms for Motivating Mobile Data Offloading in Heterogeneous Networks: A Salary-Plus-Bonus ApproachFeb 08 2018In this paper, a salary-plus-bonus incentive mechanism is proposed to motivate WiFi Access Points (APs) to provide data offloading service for mobile network operators (MNOs). Under the proposed salary-plus-bonus scheme, WiFi APs are rewarded not only ... More
On the Oort conjecture for Shimura varieties of unitary and orthogonal typesOct 21 2014Jul 27 2015In this paper we study the Oort conjecture on Shimura subvarieties contained generically in the Torelli locus in the Siegel modular variety $\mathcal{A}_g$. Using the poly-stability of Higgs bundles on curves and the slope inequality of Xiao on fibred ... More
A note on the characteristic $p$ nonabelian Hodge theory in the geometric caseFeb 17 2012Oct 24 2012We provide a construction of associating a de Rham subbundle to a Higgs subbundle in characteristic $p$ in the geometric case. As applications, we obtain a Higgs semistability result and a $W_2$-unliftable result.
Riding on the Primary: A New Spectrum Sharing Paradigm for Wireless-Powered IoT DevicesJan 20 2018In this paper, a new spectrum sharing model referred to as riding on the primary (ROP) is proposed for wireless-powered IoT devices with ambient backscatter communication capabilities. The key idea of ROP is that the secondary transmitter harvests energy ... More
On a question of Ekedahl and SerreMar 30 2017Jun 13 2017In this paper we study various aspects of the Ekedahl-Serre problem. We formulate questions of Ekedahl-Serre type and Coleman-Oort type for general weakly special subvarieties in the Siegel moduli space, propose a conjecture relating these two questions, ... More
Finiteness of hyperelliptic and superelliptic curves with CM JacobiansNov 25 2016In this paper we study the Coleman-Oort conjecture for superelliptic curves, i.e., curves defined by affine equations $y^n=F(x)$ with $F$ a separable polynomial. We prove that up to isomorphism there are at most finitely many superelliptic curves of fixed ... More
A note on Shimura subvarieties in the hyperelliptic Torelli locusApr 21 2015We prove the non-existence of Shimura subvarieties of positive dimension contained generically in the hyperelliptic Torelli locus for curves of genus at least 8, which is an analogue of Oort's conjecture in the hyperelliptic case.
Singular Fibers and Kodaira DimensionsOct 25 2016Let $f:\,X \to \mathbb{P}^1$ be a non-isotrivial semi-stable family of varieties of dimension $m$ over $\mathbb{P}^1$ with $s$ singular fibers. Assume that the smooth fibers $F$ are minimal, i.e., their canonical line bundles are semiample. Then $\kappa(X)\leq ... More
The Oort conjecture for Shimura curves of small unitary rankDec 11 2017We prove that a Shimura curve in the Siegel modular variety is not generically contained in the open Torelli locus as long as the rank of unitary part in its canonical Higgs bundle satisfies a numerical upper bound. As an application we show that the ... More
Long Short-Term AttentionOct 30 2018In order to learn effective features from temporal sequences, the long short-term memory (LSTM) network is widely applied. A critical component of LSTM is the memory cell, which is able to extract, process and store temporal information. Nevertheless, ... More
Price-Based Resource Allocation for Spectrum-Sharing Femtocell Networks: A Stackelberg Game ApproachMar 11 2011This paper investigates the price-based resource allocation strategies for the uplink transmission of a spectrum-sharing femtocell network, in which a central macrocell is underlaid with distributed femtocells, all operating over the same frequency band ... More
On Higgs bundles over Shimura varieties of ball quotient typeOct 25 2016We prove the generic exclusion of certain Shimura varieties of unitary and orthogonal types from the Torelli locus. The proof relies on a slope inequality on surface fibration due to G. Xiao, and the main result implies that certain Shimura varieties ... More
Multi-Cell Interference Exploitation: A New Dimension in Cell CoordinationJan 13 2019In this paper, we propose a series of novel coordination schemes for multi-cell downlink communication. Starting from full base station (BS) coordination, we first propose a fully-coordinated scheme to exploit beneficial effects of both inter-cell and ... More
Growth strategy of microbes on mixed carbon sourcesMar 26 2017Mar 02 2019A classic problem in microbiology is that bacteria display two types of growth behavior when cultured on a mixture of two carbon sources: the two sources are sequentially consumed one after another (diauxie) or they are simultaneously consumed (co-utilization). ... More
Random Access Analysis for Massive IoT Networks under A New Spatio-Temporal Model: A Stochastic Geometry ApproachApr 06 2017Jul 04 2018Massive Internet of Things (mIoT) has provided an auspicious opportunity to build powerful and ubiquitous connections that faces a plethora of new challenges, where cellular networks are potential solutions due to their high scalability, reliability, ... More
Optimizing DF Cognitive Radio Networks with Full-Duplex-Enabled Energy Access PointsNov 16 2016Mar 28 2017With the recent advances in radio frequency (RF) energy harvesting (EH) technologies, wireless powered cooperative cognitive radio network (CCRN) has drawn an upsurge of interest for improving the spectrum utilization with incentive to motivate joint ... More
Band renormalization and Fermi surface reconstruction in iron-based superconductorsJan 07 2009Using the fluctuation exchange approximation and a three-orbital model, we study the band renormalization, Fermi surface reconstruction and the superconducting pairing symmetry in the newly-discovered iron-based superconductors. We find that the inter-orbital ... More
Single-orbital realization of high-temperature $s^\pm$ superconductivity in the square-octagon latticeDec 31 2017May 26 2019We propose possible high-temperature superconductivity (SC) with singlet $s^\pm$-wave pairing symmetry in the single-orbital Hubbard model on the square-octagon lattice with only nearest-neighbor hopping terms. Three different approaches are engaged to ... More
On Shimura curves in the Torelli locus of curvesNov 22 2013Dec 02 2013Oort has conjectured that there do not exist Shimura curves lying generically in the Torelli locus of curves of genus $g \geq 8$. We show that there do not exist one-dimensional Shimura families of semi-stable curves of genus $g\geq 5$ of Mumford type. ... More
A Trust-based Pollution Attack Prevention Scheme in Peer-to-Peer Streaming NetworksJul 24 2014Nowadays, peer-to-peer (P2P) streaming systems have become a popular way to deliver multimedia content over the internet due to their low bandwidth requirement, high video streaming quality, and flexibility. However, P2P streaming systems are vulnerable ... More
On the slope conjecture of Barja and Stoppino for fibred surfacesApr 23 2015Apr 11 2017Let $f:\,S \to B$ be a locally non-trivial relatively minimal fibration of genus $g\geq 2$ with relative irregularity $q_f$. It was conjectured by Barja and Stoppino that the slope $\lambda_f\geq \frac{4(g-1)}{g-q_f}$. We prove the conjecture when $q_f$ ... More
On the slope of hyperelliptic fibrations with positive relative irregularityNov 28 2013Feb 11 2015Let $f:\, S \to B$ be a locally non-trivial relatively minimal fibration of hyperelliptic curves of genus $g\geq 2$ with relative irregularity $q_f$. We show a sharp lower bound on the slope $\lambda_f$ of $f$. As a consequence, we prove a conjecture ... More
Incentive Mechanism Design for Heterogeneous Peer-to-Peer Networks: A Stackelberg Game ApproachJul 24 2014With high scalability, high video streaming quality, and low bandwidth requirement, peer-to-peer (P2P) systems have become a popular way to exchange files and deliver multimedia content over the internet. However, current P2P systems are suffering from ... More
On the slope conjecture of Barja and Stoppino for fibred surfacesApr 23 2015Let $f:\,S \to B$ be a locally non-trivial relatively minimal fibration of genus $g\geq 2$ with relative irregularity $q_f$. It was conjectured by Barja and Stoppino that the slope $\lambda_f\geq \frac{4(g-1)}{g-q_f}$. We prove the conjecture when $q_f$ ... More
Possible open-charmed pentaquark molecule $Ω_c(3188)$ --- the $D Ξ$ bound state --- in the Bethe-Salpeter formalismOct 30 2017May 05 2018We study the $S$-wave $D\Xi$ bound state in the Bethe-Salpeter formalism in the ladder and instantaneous approximations. With the kernel generated by the hadronic effective Lagrangian, two open-charmed bound states, which quantum numbers are $I=0$, $J^P=(\frac{1}{2})^-$ ... More
Next-to-leading order transverse momentum broadening for Drell-Yan production in p+A collisionsMay 23 2016We present the nuclear transverse momentum broadening for Drell-Yan lepton pair production in p+A collisions at next-to-leading order (NLO) in powers of strong coupling constant $\alpha_s$. We verify that the transverse momentum weighted differential ... More
Selective-Candidate Framework with Similarity Selection Rule for Evolutionary OptimizationDec 18 2017Jan 07 2019This paper proposes a generic selective-candidate framework with similarity selection rule (SCSS) for performance enhancement of well-established evolutionary optimization algorithms. It is done by using a more efficient selective searching direction. ... More
Few-shot Object Detection via Feature ReweightingDec 05 2018This work aims to solve the challenging few-shot object detection problem where only a few annotated examples are available for each object category to train a detection model. Such an ability of learning to detect an object from just a few examples is ... More
Scaling of Dzyaloshinskii Moriya interaction at heavy metal and ferromagnetic metal interfacesSep 12 2017The Dzyaloshinskii Moriya Interaction (DMI) at the heavy metal (HM) and ferromagnetic metal (FM) interface has been recognized as a key ingredient in spintronic applications. Here we investigate the chemical trend of DMI on the 5d band filling (5d^3~5d^10) ... More
Localize energy in random media: A new phase stateNov 08 2000This Letter reports a new wave phenomenon. We show that wave energy can be stored in random media. Associated with such energy storage is a global collective behavior. The features depicted are so general that they may be observed in many random systems. ... More
Estimating the Distribution of Random Parameters in a Diffusion Equation Forward Model for a Transdermal Alcohol BiosensorAug 13 2018We estimate the distribution of random parameters in a distributed parameter model with unbounded input and output for the transdermal transport of ethanol in humans. The model takes the form of a diffusion equation with the input being the blood alcohol ... More
Single spin sensing of domain wall structure and dynamics in a thin film skyrmion hostDec 05 2018Skyrmions are nanoscale magnetic structures with features promising for future low-power memory or logic devices. In this work, we demonstrate novel scanning techniques based on nitrogen vacancy center magnetometry that simultaneously probe both the magnetic ... More
A renormalizable supersymmetric SO(10) modelApr 08 2015Jun 03 2015A realistic grand unified model has never been constructed in the literature due to three major difficulties: the seesaw mechanism without spoiling gauge coupling unification, the doublet-triplet splitting and the proton decay suppression. We propose ... More
Full-Duplex Wireless-Powered Communication Network with Energy CausalityApr 02 2014In this paper, we consider a wireless communication network with a full-duplex hybrid access point (HAP) and a set of wireless users with energy harvesting capabilities. The HAP implements the full-duplex through two antennas: one for broadcasting wireless ... More
Origins of the Isospin Violation of Dark Matter InteractionsJul 18 2011Nov 06 2012Light dark matter (DM) with a large DM-nucleon spin-independent cross section and furthermore proper isospin violation (ISV) $f_n/f_p\approx-0.7$ may provide a way to understand the confusing DM direct detection results. Combing with the stringent astrophysical ... More
Structural and electronic properties of uranium-encapsulated Au14 cageDec 26 2013The structural properties of the uranium-encapsulated nano-cage U@Au14 are predicted using density functional theory. The presence of the uranium atom makes the Au14 structure more stable than the empty Au14-cage, with a triplet ground electronic state ... More
ESE: Efficient Speech Recognition Engine with Sparse LSTM on FPGADec 01 2016Feb 20 2017Long Short-Term Memory (LSTM) is widely used in speech recognition. In order to achieve higher prediction accuracy, machine learning scientists have built larger and larger models. Such large model is both computation intensive and memory intensive. Deploying ... More
Interfacial Control of Dzyaloshinskii Moriya Interaction in Heavy Metal_Ferromagnetic Metal Thin Film HeterostructuresNov 05 2016The interfacial Dzyaloshinskii Moriya Interaction (DMI) in ultrathin magnetic thin film heterostructures provides a new approach for controlling spin textures on mesoscopic length scales. Here we investigate the dependence of the interfacial DMI constant ... More
Superconductivity in Bi3O2S2Cl with Bi-Cl Planar LayersMar 07 2019A quaternary compound Bi3O2S2Cl, which consists of novel [BiS2Cl]2-layers, is reported. It adopts a layered structure of the space group I4/mmm (No. 139) with lattice parameters: a = 3.927(1) {\AA}, c = 21.720(5) {\AA}. In this compound, bismuth and chlorine ... More
Outcome-Driven Clustering of Acute Coronary Syndrome Patients using Multi-Task Neural Network with AttentionMar 01 2019Cluster analysis aims at separating patients into phenotypically heterogenous groups and defining therapeutically homogeneous patient subclasses. It is an important approach in data-driven disease classification and subtyping. Acute coronary syndrome ... More
The Supersymmetric Standard Models with Decay and Stable Dark MattersJan 19 2010Aug 31 2010We propose two supersymmetric Standard Models (SMs) with decaying and stable dark matter (DM) particles. To explain the SM fermion masses and mixings and have a heavy decay DM particle S, we consider the Froggatt-Nielsen mechanism by introducing an anomalous ... More
Outcome-Driven Clustering of Acute Coronary Syndrome Patients using Multi-Task Neural Network with AttentionMar 01 2019Mar 27 2019Cluster analysis aims at separating patients into phenotypically heterogenous groups and defining therapeutically homogeneous patient subclasses. It is an important approach in data-driven disease classification and subtyping. Acute coronary syndrome ... More
A renormalizable supersymmetric SO(10) model with natural doublet-triplet splittingOct 21 2014Dec 08 2014We propose a renormalizable supersymmetric SO(10) model where the doublet-triplet splitting problem is solved using the Dimopoulos-Wilczek mechanism. An unwanted coupling is forbidden through a filter sector. To suppress proton decay without spoiling ... More
Evolutionary Multitasking for Single-objective Continuous Optimization: Benchmark Problems, Performance Metric, and Baseline ResultsJun 12 2017In this report, we suggest nine test problems for multi-task single-objective optimization (MTSOO), each of which consists of two single-objective optimization tasks that need to be solved simultaneously. The relationship between tasks varies between ... More
Stellar Parameters of Main Sequence Turn-off Star Candidates Observed with the LAMOST and KeplerSep 19 2016Dec 27 2017Main sequence turn-off (MSTO) stars have advantages as indicators of Galactic evolution since their ages could be robustly estimated from atmospheric parameters. Hundreds of thousands of MSTO stars have been selected from the LAMOST Galactic sur- vey ... More
Review of the three candidate hohlraums in ICFAug 07 2016In this paper, we give a review of three hohlraum geometries, including cylindrical, octahedral and six-cylinder-port hohlraums, in inertial confinement fusion (ICF) mainly from theoretical side. Every hohlraum has its own strengths and weaknesses. Although ... More
Optimizing DF Cognitive Radio Networks with Full-Duplex-Enabled Energy Access PointsNov 16 2016With the recent advances in radio frequency (RF) energy harvesting (EH) technologies, wireless powered cooperative cognitive radio network (CCRN) has drawn an upsurge of interest for improving the spectrum utilization with incentive to motivate joint ... More
Cost minimization for fading channels with energy harvesting and conventional energyApr 04 2014In this paper, we investigate resource allocation strategies for a point-to-point wireless communications system with hybrid energy sources consisting of an energy harvester and a conventional energy source. In particular, as an incentive to promote the ... More
Next-to-Leading QCD Factorization for Semi-Inclusive Deep Inelastic Scattering at Twist-4Oct 24 2013Mar 14 2014Within the framework of a high-twist approach, we calculate the next-to-leading order (NLO) perturbative QCD corrections to the transverse momentum broadening in semi-inclusive hadron production in deeply inelastic $e+A$ collisions, as well as lepton ... More
Self-Reinforced Cascaded Regression for Face AlignmentNov 23 2017Cascaded regression is prevailing in face alignment thanks to its accuracy and robustness, but typically demands manually annotated examples having low discrepancy between shape-indexed features and shape updates. In this paper, we propose a self-reinforced ... More
Bound States via Higgs Exchanging and Resonant Di-HiggsJun 05 2016Sep 18 2016The standard model (SM)-like Higgs boson $h$ has spin zero and light mass around weak scale, so it has the potential to mediate a new and relatively strong force for the particle $\phi$ in the new physics (NP) sector; then $\phi$ may form bound state ... More
Invariance property of Morse homology on noncompact manifoldsDec 27 2010In this article, we focus on the invariance property of Morse homology on noncompact manifolds. We expect to apply outcomes of this article to several types of Floer homology, thus we define Morse homology purely axiomatically and algebraically. The Morse ... More
Wetter Stratospheres on High Obliquity PlanetsApr 09 2019Apr 30 2019We investigate how obliquity affects stratospheric humidity using a 3D general circulation model and find the stratosphere under high obliquity could be over 3 orders of magnitude moister than under the low obliquity equivalent, even with the same global ... More
Mechanisms leading to a warmer climate on high obliquity planetsMar 09 2019Apr 09 2019A consistent finding of high obliquity simulations is that they are warmer than their low obliquity counterparts when the climate is cold. Ice-albedo feedback has been suggested as a possible mechanism. In this study, we find that warmer climate under ... More
On the Rate of Convergence for the Pseudospectral Optimal Control of Feedback Linearizable SystemsApr 06 2009In this paper, we prove a theorem on the rate of convergence for the optimal cost computed using PS methods. It is a first proved convergence rate in the literature of PS optimal control. In addition to the high-order convergence rate, two theorems are ... More
$\mathbb{Z}_{2}$-equivariant Heegaard Floer cohomology of knots in $S^{3}$ as a strong Heegaard invariantOct 03 2018The $\mathbb{Z}_{2}$-equivariant Heegaard Floer cohomlogy $\widehat{HF}_{\mathbb{Z}_{2}}(\Sigma(K))$ of a knot $K$ in $S^{3}$, constructed by Hendricks, Lipshitz, and Sarkar, is an isotopy invariant which is defined using bridge diagrams of $K$ drawn ... More
Leptonic Charm DecaysJan 14 2011Jan 17 2011We review the recent experimental results on D and Ds meson leptonic decays from CLEO-c, Belle, and BABAR, which results in the decay constants f_D= (206.7 +- 8.9) MeV and f_Ds= (257.3 +- 5.3) MeV. The latter is an average obtained by the Heavy Flavor ... More
KPP Front Speeds in Random Shears and the Parabolic Anderson ProblemDec 19 2002We study the asymptotics of front speeds of the reaction-diffusion equations with Kolmogorov-Petrovsky-Piskunov (KPP) nonlinearity and zero mean stationary ergodic Gaussian shear advection on the entire plane. By exploiting connections of KPP front speeds ... More
A new approach to recent constructions of C*-algebras from modular index theoryAug 18 2014We present a new approach to C*-algebras recently constructed in the context of modular index theory by Carey, Phillips, Putnam and Rennie. It turns out that their constructions can be identified with full corners of ideals in semigroup C*-algebras. This ... More
Effective Non-vanishing of Asymptotic Adjoint SyzygiesMar 31 2012Apr 08 2014The purpose of this paper is to establish an effective non-vanishing theorem for the syzygies of an adjoint-type line bundle on a smooth variety, as the positivity of the embedding increases. Our purpose here is to show that for an adjoint type divisor ... More
On Irreducible weight representations of a new deformation $U_{q}(sl_{2})$ of $U(sl_{2})$Oct 29 2006Starting from a Hecke $R-$matrix, Jing and Zhang constructed a new deformation $U_{q}(sl_{2})$ of $U(sl_{2})$, and studied its finite dimensional representations in \cite{JZ}. Especically, this algebra is proved to be just a bialgebra, and all finite ... More
Well-posedness of strong solutions to the anelastic equations for viscous flowsMar 04 2019We address the local and global well-posedness issues of strong solutions to the anelastic equations for viscous flows. The density profile is taken to satisfy physical vacuum singularity, and the interaction of the density profile with the velocity fields ... More
Quantum groups, q-Boson algebras and quantized Weyl algebrasApr 01 2010Sep 13 2010We give a unified construction of quantum groups, q-Boson algebras and quantized Weyl algebras and an action of quantum groups on quantized Weyl algebras. This enables us to give a conceptual proof of the semi-simplicity of the category $\mathcal{O}(B_q)$ ... More
Dedekind η-function and quantum groupsMay 02 2012Aug 10 2015We realize some powers of Dedekind $\eta$-function as traces on quantum coordinate algebras.
Representing the big tilting sheaves as holomorphic Morse branesFeb 24 2016Feb 28 2016We introduce Morse branes in the Fukaya category of a holomorphic symplectic manifold, with the goal of constructing tilting objects in the category. We give a construction of a class of Morse branes in the cotangent bundles, and apply it to give the ... More
A remote response of ATP hydrolysisApr 28 2013ATP-hydrolysis is the basic energy source of many physiological processes, but there is a lack of knowledge regarding its biological role other than energy transfer and thermogenesis. Not all the energy released by ATP-hydrolysis could be used in powering ... More
A genus-4 topological recursion relation for Gromov-Witten invariantsAug 18 2016In this paper, we give a new genus-4 topological recursion relation for Gromov-Witten invariants of compact symplectic manifolds via Pixton's relations on the moduli space of curves. As an application, we prove Pixton's relations imply a known topological ... More
Frobenius splitting of projective toric bundlesApr 08 2014We give several mild conditions on a toric bundle on a nonsingular toric variety under which the projectivization of the toric bundle is Frobenius split.
Non-Malleable Extractors and Non-Malleable Codes: Partially Optimal ConstructionsApr 09 2018The recent line of study on randomness extractors has been a great success, resulting in exciting new techniques, new connections, and breakthroughs to long standing open problems in several seemingly different topics. These include seeded non-malleable ... More
Code Generation Techniques for Raw Data ProcessingDec 09 2017The motivation of the current study was to design an algorithm that can speed up the processing of a query. The important feature is generating code dynamically for a specific query. We present the technique of code generation that is applied to query ... More
An efficient search algorithm for inverting the sweep map on rational Dyck pathsMay 04 2015Given a coprime pair $(m,n)$ of positive integers, rational $(m,n)$-Dyck paths are lattice paths in the $m\times n$ rectangle that never go below the diagonal. The sweep map of a rational $(m,n)$-Dyck paths $D$ is the rational Dyck path $\Phi(D)$ obtained ... More
Semigroup C*-algebras of $ax+b$-semigroupsJun 24 2013We study semigroup C*-algebras of $ax+b$-semigroups over integral domains. The goal is to generalize several results about C*-algebras of $ax+b$-semigroups over rings of algebraic integers. We prove results concerning K-theory and structural properties ... More
Nuclearity of semigroup C*-algebras and the connection to amenabilityFeb 29 2012May 11 2012We study C*-algebras associated with subsemigroups of groups. For a large class of such semigroups including positive cones in quasi-lattice ordered groups and left Ore semigroups, we describe the corresponding semigroup C*-algebras as C*-algebras of ... More
On K-theoretic invariants of semigroup C*-algebras attached to number fieldsDec 13 2012We show that semigroup C*-algebras attached to ax+b-semigroups over rings of integers determine number fields up to arithmetic equivalence, under the assumption that the number fields have the same number of roots of unity. For finite Galois extensions, ... More
Semigroup C*-algebras and amenability of semigroupsMay 27 2011Feb 22 2012We construct reduced and full semigroup C*-algebras for left cancellative semigroups. Our new construction covers particular cases already considered by A. Nica and also Toeplitz algebras attached to rings of integers in number fields due to J. Cuntz. ... More
On Schauder Equivalence RelationsNov 02 2014In this paper, we study Schauder equivalence relations, which are Borel equivalence relations generated by Banach spaces with basic sequences. We prove that the set of equivalence relations generated by basic sequences has boundaries. Then we show that ... More
On the Expanding Configurations of Viscous Radiation Gaseous Stars: Isentropic and Thermodynamic ModelsOct 17 2017Oct 19 2017In this work, we study the stability of the expanding configurations for radiation gaseous stars. Such expanding configurations exist for the isentropic model and the thermodynamic model. In particular, we focus on the effect of the monatomic gas viscosity ... More
The gap distribution of directions in some Schottky groupsNov 25 2015Oct 04 2016We prove the existence and some properties of the limiting gap distribution functions for the directions of orbits of some infinite covolume subgroups of $Isom(\mathbb{H}^2)$ in the Poincar\'e disk.
Impacts of dark energy on weighing neutrinos after Planck 2015Nov 09 2015Apr 21 2016We investigate how dark energy properties impact the cosmological limits on the total mass of active neutrinos. We consider two typical, simple dark energy models (that have only one more additional parameter than $\Lambda$CDM), i.e., the $w$CDM model ... More
Improved Constructions of Two-Source ExtractorsAug 05 2015In a recent breakthrough \cite{CZ15}, Chattopadhyay and Zuckerman gave an explicit two-source extractor for min-entropy $k \geq \log^C n$ for some large enough constant $C$. However, their extractor only outputs one bit. In this paper, we improve the ... More
Local convergence of critical random trees and continuous-state branching processesMar 03 2015Aug 09 2015We study the local convergence of critical Galton-Watson trees and Levy trees under various conditionings. Assuming a very general monotonicity property on the functional of random trees, we show that random trees conditioned to have large functional ... More
Conditioning Galton-Watson trees on large maximal out-degreeDec 05 2014We propose a new way to condition random trees, that is, condition random trees to have large maximal out-degree. Under this new conditioning, we show that conditioned critical Galton-Watson trees converge locally to size-biased trees with a unique infinite ... More
Equitable list point arboricity of graphsMar 12 2014A graph $G$ is list point $k$-arborable if, whenever we are given a $k$-list assignment $L(v)$ of colors for each vertex $v\in V(G)$, we can choose a color $c(v)\in L(v)$ for each vertex $v$ so that each color class induces an acyclic subgraph of $G$, ... More
The edge chromatic number of outer-1-planar graphsMay 13 2014May 14 2014A graph is outer-1-planar if it can be drawn in the plane so that all vertices are on the outer face and each edge is crossed at most once. In this paper, we completely determine the edge chromatic number of outer 1-planar graphs.
The Rigorous Stochastic Matrix Multiplication Scheme for the Calculations of Reduced Equilibrium Density Matrices of Open Multilevel Quantum SystemsOct 28 2013Mar 28 2014Understanding the roles of the temporary and spatial structures of quantum functional noise in open multilevel quantum molecular systems attracts a lot of theoretical interests. I want to establish a rigorous and general framework for functional quantum ... More
Algebra endomorphisms and Derivations of Some Localized Down-Up AlgebrasMar 26 2014We study algebra endomorphisms and derivations of some localized down-up algebras $\A$. First, we determine all the algebra endomorphisms of $\A$ under some conditions on $r$ and $s$. We show that each algebra endomorphism of $\A$ is an algebra automorphism ... More
Two-Parameter Quantum Groups and Ringel-Hall algebras of $A_{\infty}-$typeJun 09 2011Jul 04 2011In this paper, we study the two-parameter quantum group $U_{r,s}(\mathfrak sl_{\infty})$ associated to the Lie algebra $\mathfrak sl_{\infty}$ of infinite rank. We shall prove that the two-parameter quantum group $U_{r,s}(\mathfrak sl_{\infty})$ admits ... More
Mixture Diffusion for Asset PricingOct 05 2016Oct 12 2016This paper proposes a general form of mixture diffusion process to model asset price dynamics, using a mixture of infinite number of parametric diffusions. We show that the underlying asset price dynamics of the risk-neutral probability density distributions ... More
Analysis of some singular solutions in fluid dynamicsMay 01 2003Studies on singular flows in which either the velocity fields or the vorticity fields change dramatically on small regions are of considerable interests in both the mathematical theory and applications. Important examples of such flows include supersonic ... More
Generalized Strichartz Estimates on Perturbed Wave Equation and Applications on Strauss ConjectureMay 01 2009Jan 26 2011In this paper we show a general Strichartz estimate for certain perturbed wave equation, and here we can drop the nontrapping hypothesis and handle trapping obstacles with some loss of derivatives for data in the local energy decay estimates. Then we ... More
On defining ideals and differential algebras of Nichols algebrasApr 05 2011Sep 15 2011This paper is devoted to understanding the defining ideal of a Nichols algebra from the decomposition of specific elements in the group algebra of braid groups. A family of primitive elements are found and algorithms are proposed. To prove the main result, ... More
Non-symmetrizable quantum groups: defining ideals and specializationMar 24 2013May 06 2014Two generating sets of the defining ideal of a Nichols algebra of diagonal type are proposed, which are then applied to study the bar involution and the specialization problem of quantum groups associated to non-symmetrizable generalized Cartan matrices. ... More
Transverse momentum broadening in semi-inclusive deep inelastic scattering at next-to-leading orderSep 04 2014Dec 26 2016Within the framework of higher-twist collinear factorization, transverse momentum broadening for the final hadrons in semi-inclusive deeply inelastic $e+A$ collisions is studied at the next-to-leading order (NLO) in perturbative QCD. Through explicit ... More
Modulation of pairing symmetry with bond disorder in unconventional superconductorsJan 13 2017Apr 21 2017We study a two-orbital $t$-$J_1$-$J_2$ model, originally developed to describe iron-based superconductors at low energies, in the presence of bond disorder (via next-nearest-neighbor $J_2$-bond dilution). By using the Bogoliubov--de Gennes approach, we ... More
On the minimal number of singular fibers with non-compact Jacobians for families of curves over $\mathbb P^1$Sep 23 2014Let $f:X \to \mathbb{P}^1$ be a non-isotrivial family of semi-stable curves of genus $g\geq 1$ defined over an algebraically closed field $k$ with $s_{nc}$ singular fibers whose Jacobians are non-compact. We prove that $s_{nc}\geq 5$ if $k=\mathbb C$ ... More
Signal of quark deconfinement and thermal evolution of hybrid starsJun 01 2010It is well known that neutron stars spin down due to magnetic dipole radiation. The deconfinement phase transition of hadron matter to quark matter is expected to occur in the dense cores of the stars during spin-down. The phase transition continuously ... More
Hajós-like theorem for signed graphsFeb 27 2017The paper designs five graph operations, and proves that every signed graph with chromatic number $q$ can be obtained from all-positive complete graphs $(K_q,+)$ by repeatedly applying these operations. This result gives a signed version of the Haj\'os ... More
Single-orbital realization of high temperature $s^\pm$ superconductivity in the square-octagon latticeDec 31 2017Jan 16 2019We propose possible high-temperature superconductivity with singlet $s^\pm$-wave pairing symmetry in the octagraphene, i.e. a monolayer of carbon atoms arranged into the square-octagon lattice. Starting from a tight-binding model which well describes ... More