Results for "Yuyin Zhou"

total 13486took 0.12s
Prior-aware Neural Network for Partially-Supervised Multi-Organ SegmentationApr 12 2019Accurate multi-organ abdominal CT segmentation is essential to many clinical applications such as computer-aided intervention. As data annotation requires massive human labor from experienced radiologists, it is common that training data are partially ... More
Semi-Supervised Multi-Organ Segmentation via Deep Multi-Planar Co-TrainingApr 07 2018Nov 19 2018In multi-organ segmentation of abdominal CT scans, most existing fully supervised deep learning algorithms require lots of voxel-wise annotations, which are usually difficult, expensive, and slow to obtain. In comparison, massive unlabeled 3D CT volumes ... More
Training Multi-organ Segmentation Networks with Sample Selection by Relaxed Upper Confident BoundApr 07 2018Deep convolutional neural networks (CNNs), especially fully convolutional networks, have been widely applied to automatic medical image segmentation problems, e.g., multi-organ segmentation. Existing CNN-based segmentation methods mainly focus on looking ... More
Deep Supervision for Pancreatic Cyst Segmentation in Abdominal CT ScansJun 22 2017Automatic segmentation of an organ and its cystic region is a prerequisite of computer-aided diagnosis. In this paper, we focus on pancreatic cyst segmentation in abdominal CT scan. This task is important and very useful in clinical practice yet challenging ... More
Improving Transferability of Adversarial Examples with Input DiversityMar 19 2018Jun 11 2018Though convolutional neural networks have achieved state-of-the-art performance on various vision tasks, they are extremely vulnerable to adversarial examples, which are obtained by adding human-imperceptible perturbations to the original images. Adversarial ... More
Improving Transferability of Adversarial Examples with Input DiversityMar 19 2018Jun 01 2019Though CNNs have achieved the state-of-the-art performance on various vision tasks, they are vulnerable to adversarial examples --- crafted by adding human-imperceptible perturbations to clean images. However, most of the existing adversarial attacks ... More
Improving Transferability of Adversarial Examples with Input DiversityMar 19 2018Mar 27 2019Though CNNs have achieved the state-of-the-art performance on various vision tasks, they are vulnerable to adversarial examples --- crafted by adding human-imperceptible perturbations to clean images. However, most of the existing adversarial attacks ... More
Piecewise constructions of inverses of cyclotomic mapping permutation polynomialsOct 14 2015Dec 19 2018Given a permutation polynomial of a large finite field, finding its inverse is usually a hard problem. Based on a piecewise interpolation formula, we construct the inverses of cyclotomic mapping permutation polynomials of arbitrary finite fields.
Adversarial Examples for Semantic Segmentation and Object DetectionMar 24 2017Jul 21 2017It has been well demonstrated that adversarial examples, i.e., natural images with visually imperceptible perturbations added, generally exist for deep networks to fail on image classification. In this paper, we extend adversarial examples to semantic ... More
Visual Concepts and Compositional VotingNov 13 2017It is very attractive to formulate vision in terms of pattern theory \cite{Mumford2010pattern}, where patterns are defined hierarchically by compositions of elementary building blocks. But applying pattern theory to real world images is currently less ... More
A Fixed-Point Model for Pancreas Segmentation in Abdominal CT ScansDec 25 2016Jun 21 2017Deep neural networks have been widely adopted for automatic organ segmentation from abdominal CT scans. However, the segmentation accuracy of some small organs (e.g., the pancreas) is sometimes below satisfaction, arguably because deep networks are easily ... More
Learning Transferable Adversarial Examples via Ghost NetworksDec 09 2018Feb 26 2019Recent development of adversarial attacks has proven that ensemble-based methods outperform traditional, non-ensemble ones in black-box attack. However, these methods generally require a family of diverse models, and ensembling them together afterward, ... More
Multi-Scale Attentional Network for Multi-Focal Segmentation of Active Bleed after Pelvic FracturesJun 23 2019Trauma is the worldwide leading cause of death and disability in those younger than 45 years, and pelvic fractures are a major source of morbidity and mortality. Automated segmentation of multiple foci of arterial bleeding from abdominopelvic trauma CT ... More
Recurrent Saliency Transformation Network: Incorporating Multi-Stage Visual Cues for Small Organ SegmentationSep 13 2017Apr 08 2018We aim at segmenting small organs (e.g., the pancreas) from abdominal CT scans. As the target often occupies a relatively small region in the input image, deep neural networks can be easily confused by the complex and variable background. To alleviate ... More
Adversarial Metric Attack for Person Re-identificationJan 30 2019Person re-identification (re-ID) has attracted much attention recently due to its great importance in video surveillance. In general, distance metrics used to identify two person images are expected to be robust under various appearance changes. However, ... More
Metric Attack and Defense for Person Re-identificationJan 30 2019Mar 23 2019Person re-identification (re-ID) has attracted much attention recently due to its great importance in video surveillance. In general, distance metrics used to identify two person images are expected to be robust under various appearance changes. However, ... More
Abdominal multi-organ segmentation with organ-attention networks and statistical fusionApr 23 2018Accurate and robust segmentation of abdominal organs on CT is essential for many clinical applications such as computer-aided diagnosis and computer-aided surgery. But this task is challenging due to the weak boundaries of organs, the complexity of the ... More
Does Quantum Interference exist in Twitter?Jul 04 2011It becomes more difficult to explain the social information transfer phenomena using the classic models based merely on Shannon Information Theory (SIT) and Classic Probability Theory (CPT), because the transfer process in the social world is rich of ... More
On the Glide of 3x+1 ProblemOct 04 2017Oct 08 2017For any positive integer $n$, define an iterated function $$ f(n)=\left\{\begin{array}{ll} n/2, & \mbox{$n$ even,} \\ 3n+1, & \mbox{$n$ odd.} \end{array} \right. $$ Suppose $k$ (if it exists) is the lowest number such that $f^{k}(n)<n$, and there are ... More
Chem2Bio2RDF: A Linked Open Data Portal for Chemical BiologyDec 21 2010The Chem2Bio2RDF portal is a Linked Open Data (LOD) portal for systems chemical biology aiming for facilitating drug discovery. It converts around 25 different datasets on genes, compounds, drugs, pathways, side effects, diseases, and MEDLINE/PubMed documents ... More
Nonparametric specification for non-stationary time series regressionFeb 04 2014We investigate the behavior of the Generalized Likelihood Ratio Test (GLRT) (Fan, Zhang and Zhang [Ann. Statist. 29 (2001) 153-193]) for time varying coefficient models where the regressors and errors are non-stationary time series and can be cross correlated. ... More
Inference of weighted $V$-statistics for nonstationary time series and its applicationsJan 16 2014We investigate the behavior of Fourier transforms for a wide class of nonstationary nonlinear processes. Asymptotic central and noncentral limit theorems are established for a class of nondegenerate and degenerate weighted $V$-statistics through the angle ... More
Non-zero-sum stopping games in continuous timeAug 17 2015On a filtered probability space $(\Omega ,\mathcal{F}, (\mathcal{F}_t)_{t\in[0,\infty]}, \mathbb{P})$, we consider the two-player non-zero-sum stopping game $u^i := \mathbb{E}[U^i(\rho,\tau)],\ i=1,2$, where the first player choose a stopping strategy ... More
Piecewise constructions of inverses of cyclotomic mapping permutationsOct 14 2015Given a permutation polynomial $f(x)$ of a small finite field $\mathbb{F}_q$, the inverse $f^{-1}(x)$ over $\mathbb{F}_q$ could be determined by using the Lagrange Interpolation Formula. But for a large $q$, finding the explicit expression of $f^{-1}(x)$ ... More
Multi-player stopping games in continuous timeSep 14 2015We consider multi-player stopping games in continuous time. Unlike Dynkin games, in our games the payoff of each player is revealed after all the players stop. Moreover, each player can adjust her own stopping strategy by observing other players' behaviors. ... More
Non-zero-sum stopping games in discrete timeAug 25 2015We consider two-player non-zero-sum stopping games in discrete time. Unlike Dynkin games, in our games the payoff of each player is revealed after both players stop. Moreover, each player can adjust her own stopping strategy according to the other player's ... More
Nonparametric inference of quantile curves for nonstationary time seriesOct 19 2010The paper considers nonparametric specification tests of quantile curves for a general class of nonstationary processes. Using Bahadur representation and Gaussian approximation results for nonstationary time series, simultaneous confidence bands and integrated ... More
Building Hierarchies of Concepts via CrowdsourcingApr 27 2015Aug 01 2015Hierarchies of concepts are useful in many applications from navigation to organization of objects. Usually, a hierarchy is created in a centralized manner by employing a group of domain experts, a time-consuming and expensive process. The experts often ... More
Channel Estimation for Millimeter Wave MIMO-OFDM Systems via Low-Rank Tensor DecompositionSep 12 2016In millimeter-wave (mmWave) MIMO systems, both the base stations (BS) and the mobile stations (MSs) employ large antenna arrays for directional beamforming. Acquiring channel knowledge for beamforming transmission is challenging due to the large number ... More
On Zero-sum Optimal Stopping GamesAug 16 2014May 08 2015On a filtered probability space $(\Omega,\mathcal{F},P,\mathbb{F}=(\mathcal{F}_t)_{t=0,\dotso,T})$, we consider stopper-stopper games $\overline V:=\inf_{\Rho\in\bT^{ii}}\sup_{\tau\in\T}\E[U(\Rho(\tau),\tau)]$ and $\underline V:=\sup_{\Tau\in\bT^i}\inf_{\rho\in\T}\E[U(\Rho(\tau),\tau)]$ ... More
On utility maximization with derivatives under model uncertaintyJul 18 2013We consider the robust utility maximization using a static holding in derivatives and a dynamic holding in the stock. There is no fixed model for the price of the stock but we consider a set of probability measures (models) which are not necessarily dominated ... More
No-arbitrage and hedging with liquid American optionsMay 04 2016May 27 2016Since most of the traded options on individual stocks is of American type it is of interest to generalize the results obtained in semi-static trading to the case when one is allowed to statically trade American options. However, this problem has proved ... More
Estimation and inference for precision matrices of non-stationary time seriesMar 03 2018Apr 18 2018In this paper, we consider the estimation and inference of precision matrices of a rich class of locally stationary and nonlinear time series assuming that only one realization of the time series is observed. Using a Cholesky decomposition technique, ... More
Estimation and inference for precision matrices of non-stationary time seriesMar 03 2018Mar 25 2019In this paper, we consider the estimation and inference of precision matrices of a rich class of locally stationary and nonlinear time series assuming that only one realization of the time series is observed. Using a Cholesky decomposition technique, ... More
Arbitrage, hedging and utility maximization using semi-static trading strategies with American optionsFeb 24 2015Feb 08 2016We consider a financial market where stocks are available for dynamic trading, and European and American options are available for static trading (semi-static trading strategies). We assume that the American options are infinitely divisible, and can only ... More
On controller-stopper problems with jumps and their applications to indifference pricing of American optionsDec 20 2012Nov 18 2013We consider controller-stopper problems in which the controlled processes can have jumps. The global filtration is represented by the Brownian filtration, enlarged by the filtration generated by the jump process. We assume that there exists a conditional ... More
Spectral Inference under Complex Temporal DynamicsDec 19 2018Dec 31 2018We develop unified theory and methodology for the inference of evolutionary Fourier power spectra for a general class of locally stationary and possibly nonlinear processes. In particular, simultaneous confidence regions (SCR) with asymptotically correct ... More
Ground-State Entropy of the Random Vertex-Cover ProblemOct 03 2008Mar 17 2009Counting the number of ground states for a spin-glass or NP-complete combinatorial optimization problem is even more difficult than the already hard task of finding a single ground state. In this paper the entropy of minimum vertex-covers of random graphs ... More
On a Stopping Game in continuous timeSep 23 2014Jul 24 2015We consider a zero-sum continuous time stopping game in which the pay-off is revealed in the maximum of the two stopping times instead of the minimum, which is the case in Dynkin games.
On model-independent pricing/hedging using shortfall risk and quantilesJul 09 2013We consider the pricing and hedging of exotic options in a model-independent set-up using \emph{shortfall risk and quantiles}. We assume that the marginal distributions at certain times are given. This is tantamount to calibrating the model to call options ... More
On an Optimal Stopping Problem of an InsiderJan 14 2013Apr 06 2015We consider the optimal stopping problem $v^{(\eps)}:=\sup_{\tau\in\mathcal{T}_{0,T}}\mathbb{E}B_{(\tau-\eps)^+}$ posed by Shiryaev at the International Conference on Advanced Stochastic Optimization Problems organized by the Steklov Institute of Mathematics ... More
A Note on Two Constructions of Zero-Difference Balanced FunctionsNov 19 2018Nov 28 2018Notes on two constructions of zero-difference balanced (ZDB) functions are made in this letter. Then ZDB functions over $\mathbb{Z}_{e}\times \prod_{i=0}^{k}{\mathbb{F}_{q_i}}$ are obtained. And it shows that all the known ZDB functions using cyclotomic ... More
On Arbitrage and Duality under Model Uncertainty and Portfolio ConstraintsFeb 11 2014Mar 27 2015We consider the fundamental theorem of asset pricing (FTAP) and hedging prices of options under non-dominated model uncertainty and portfolio constrains in discrete time. We first show that no arbitrage holds if and only if there exists some family of ... More
Super-hedging American Options with Semi-static Trading Strategies under Model UncertaintyApr 15 2016We consider the super-hedging price of an American option in a discrete-time market in which stocks are available for dynamic trading and European options are available for static trading. We show that the super-hedging price $\pi$ is given by the supremum ... More
Convex Polytopes for the Central Degeneration of the Affine GrassmannianApr 28 2016Aug 30 2016We study the central degeneration (the degeneration that shows up in local models of Shimura varieties and Gaitsgory's central sheaves) of semi-infinite orbits, MV Cycles, and Iwahori orbits in the affine Grassmannian of type A, by considering their moment ... More
Infinite Edge Partition Models for Overlapping Community Detection and Link PredictionJan 25 2015Dec 30 2015A hierarchical gamma process infinite edge partition model is proposed to factorize the binary adjacency matrix of an unweighted undirected relational network under a Bernoulli-Poisson link. The model describes both homophily and stochastic equivalence, ... More
Rational curves and lines on the moduli space of stable bundlesMay 15 2013Aug 06 2014Fix a smooth projetive curve $\mathcal {C}$ of genus $g\geq 2$ and a line bundle $\mathcal{L}$ on $\mathcal{C}$ of degree $d$. Let $M:= \mathcal{SU}_{\mathcal{C}}(r, \mathcal{L})$ be the moduli space of stable vector bundles on $\mathcal{C}$ of rank $r$ ... More
Spherically symmetric Finsler metrics in R^nJun 19 2010In this paper, we give the general form of spherically symmetric Finsler metrics in $R^n$ and surprisedly find that many well-known Finsler metrics belong to this class. Then we explicitly express projective metrics of this type. The necessary and sufficient ... More
Update on two-zero textures of the Majorana neutrino mass matrix in light of recent T2K, Super-Kamiokande and NO$ν$A resultsSep 17 2015Dec 25 2015The latest results from atmospheric and accelerator neutrino experiments indicate that the normal neutrino mass ordering $m^{}_1 < m^{}_2 < m^{}_3$, a maximal leptonic CP-violating phase $\delta = 270^\circ$ and the second octant of neutrino mixing angle ... More
Total perfect codes in Cayley graphsJan 14 2016A total perfect code in a graph $\Gamma$ is a subset $C$ of $V(\Gamma)$ such that every vertex of $\Gamma$ is adjacent to exactly one vertex in $C$. We give necessary and sufficient conditions for a conjugation-closed subset of a group to be a total perfect ... More
Theoretical Results on NeutrinosNov 23 2015In this talk, I first summarize our current knowledge about the fundamental properties of neutrinos and emphasize the remaining unsolved problems in neutrino physics. Then, recent theoretical results on neutrino mass models are introduced. Different approaches ... More
Learning Balanced Mixtures of Discrete Distributions with Small SampleFeb 10 2008We study the problem of partitioning a small sample of $n$ individuals from a mixture of $k$ product distributions over a Boolean cube $\{0, 1\}^K$ according to their distributions. Each distribution is described by a vector of allele frequencies in $\R^K$. ... More
Neutrino Decays and Neutrino Electron Elastic Scattering in Unparticle PhysicsJun 03 2007Oct 30 2007Following Georgi's unparticle scheme, we examine the effective couplings between neutrinos and unparticle operators. As an immediate consequence, neutrinos become unstable and can decay into the unparticle stuff. Assuming the dimension transmutation scale ... More
Legendre Functions, Spherical Rotations, and Multiple Elliptic IntegralsJan 09 2013Apr 29 2013A closed-form formula is derived for the generalized Clebsch-Gordan integral $ \int_{-1}^1 {[}P_{\nu}(x){]}^2P_{\nu}(-x)\D x$, with $ P_\nu$ being the Legendre function of arbitrary complex degree $ \nu\in\mathbb C$. The finite Hilbert transform of $ ... More
Structure Learning of Probabilistic Graphical Models: A Comprehensive SurveyNov 29 2011Probabilistic graphical models combine the graph theory and probability theory to give a multivariate statistical modeling. They provide a unified description of uncertainty using probability and complexity using the graphical model. Especially, graphical ... More
D4 brane probes in gauge/gravity dualitySep 08 2008Feb 26 2009We propose a DBI vertex brane + $N_c$ fundamental strings configuration for a probe baryon in the finite-temperature thermal gauge field via AdS/CFT correspondence. In particular, we investigate properties of this configuration in QCD_4 and warped AdS_6\times ... More
Gauge dependence of fermion mass renormalization schemesOct 06 2005Dec 09 2005We discuss the gauge dependence of fermion mass definition and physical result under the conventional on-shell mass renormalization scheme and the recently proposed pole mass renormalization scheme in standard model. By the two-loop calculations of top ... More
Singularity of Feynman propagator and Cutkosky's cutting rulesAug 22 2005May 20 2010We improve on Cutkosky's cutting rules which is used to calculate the contribution of the singularities of Feynman propagators to Feynman amplitude. The correctness of the improved cutting rules is verified by the calculations of the conventional loop ... More
Unstable particle's wave-function renormalization prescriptionFeb 21 2005Dec 17 2005We strictly define two set Wave-function Renormalization Constants (WRC) under the LSZ reduction formula for unstable particles at the first time. Then by introducing antiparticle's WRC and the CPT conservation law we obtain a new wave-function renormalization ... More
Minimal Control Selection for a Networked SystemOct 01 2016Dec 04 2016This paper investigates the minimal number of actuators required to guarantees the controllability of a system, under the condition that its state transition matrix (STM) is prescribed. It has been proved that this minimal number is equal to the maximum ... More
A Rolling PID Control Approach and its ApplicationsApr 09 2016The canonical proportional-integral-derivative (PID) control approach has been widely used in industrial application due to their simplicity and ease of use. However, its corresponding controller parameters are hard to be adjusted, especially for nonlinear ... More
A matlab toolbox for continuous state transition algorithmApr 04 2016State transition algorithm (STA) has been emerging as a novel stochastic method for global optimization in recent few years. To make better understanding of continuous STA, a matlab toolbox for continuous STA has been developed. Firstly, the basic principles ... More
Inverse mean curvature flows in warped product manifoldsSep 30 2016Oct 28 2016We study inverse mean curvature flows of starshaped, mean convex hypersurfaces in warped product manifolds with a positive warping factor $h(r)$. If $h'(r)>0$ and $h"(r)\geq 0$, we show that these flows exist for all times, remain starshaped and mean ... More
Global well-posedness and random attractor of the 3D viscous primitive equations driven by fractional noisesApr 18 2016In this article we study the perturbation of primitive equations (PEs) of large-scale ocean and atmosphere dynamics defined on a bounded open subset $\mho \in \mathbb{R}^{3}$ and driven by infinite-dimensional additive fractional Wiener processes with ... More
Relations among Out-degree, Controllability and Observability of a Networked SystemOct 07 2016Some novel sufficient conditions are derived respectively for the controllability and observability of a networked system, as well as some necessary conditions. These conditions depends only separately on parameters of each subsystem and its out-degree. ... More
Probing the $P$-wave charmonium decays of $B_c$ mesonDec 24 2017Feb 13 2018Motivated by the large number of $B_c$ meson decay modes observed recently by several detectors at the LHC, we present a detailed analysis of the $B_c$ meson decaying to the $P$-wave charmonium states and a light pseudoscalar($P$) or vector ($V$) meson ... More
The Geometry and Topology on Grassmann ManifoldsAug 03 2006This paper shows that the Grassmann Manifolds $G_{\bf F}(n,N)$ can all be imbedded in an Euclidean space $M_{\bf F}(N)$ naturally and the imbedding can be realized by the eigenfunctions of Laplacian $\triangle$ on $G_{\bf F}(n,N)$. They are all minimal ... More
Per-Flow Cardinality Estimation Based On Virtual LogLog SketchingNov 30 2018Flow cardinality estimation is the problem of estimating the number of distinct elements in a data flow, often with a stringent memory constraint. It has wide applications in network traffic measurement and in database systems. The virtual LogLog algorithm ... More
Empirical effect of graph embeddings on fraud detection/ risk mitigationMar 05 2019Graph embedding technics are studied with interest on public datasets, such as BlogCatalog, with the common practice of maximizing scoring on graph reconstruction, link prediction metrics etc. However, in the financial sector the important metrics are ... More
Effective upper bound of analytic torsion under Arakelov metricMar 20 2019Mar 26 2019Given a choice of metric on the Riemann surface, the regularized determinant of Laplacian (analytic torsion) is defined via the complex power of elliptic operators: $$ \det(\Delta)=\exp(-\zeta'(0)) $$ In this paper we gave an asymptotic effective estimate ... More
$K$-stable splendid Rickard complexesMar 04 2014In this paper, Brou\'e's conjecture is reduced to simple groups, with an additional stability condition.
Effect of Singwi-Tosi-Land-Sjölander local field correction on spin relaxation in $n$-type GaAs quantum wells at low temperatureDec 20 2007Feb 22 2008We study the effect of the Singwi-Tosi-Land-Sj\"{o}lander local field correction on spin relaxation/dephasing in $n$-type GaAs quantum wells at low temperature by constructing and numerically solving the kinetic spin Bloch equations. We calculate the ... More
Temporal evolution and scaling of mixing in two-dimensional Rayleigh-Taylor turbulenceAug 01 2013We report a high-resolution numerical study of two-dimensional (2D) miscible Rayleigh-Taylor (RT) incompressible turbulence with the Boussinesq approximation. An ensemble of 100 independent realizations were performed at small Atwood number and unit Prandtl ... More
The first boundary value problem for Abreu's equationSep 09 2010In this paper we prove the existence and regularity of solutions to the first boundary value problem for Abreu's equation, which is a fourth order nonlinear partial differential equation closely related to the Monge-Ampere equation. The first boundary ... More
A Necessary and Sufficient Condition for Stability of Linear Difference Equations with Two DelaysAug 26 2018This note provides a necessary and sufficient condition for guaranteeing exponential stability of the linear difference equation $x(t)=Ax(t-a)+Bx(t-b)$ where $a>0,b>0$ are constants and $A,B$ are $n\times n$ square matrices, in terms of a linear matrix ... More
Stability Analysis of Nonlinear Time-Varying Systems by Lyapunov Functions with Indefinite DerivativesDec 08 2015This paper is concerned with stability analysis of nonlinear time-varying systems by using Lyapunov function based approach. The classical Lyapunov stability theorems are generalized in the sense that the time-derivative of the Lyapunov functions are ... More
Formulation of finite-time singularity for free-surface Euler equationsNov 19 2012Dec 21 2012We give an extremely short proof that the free-surface incompressible, irrotational Euler equations with regular initial condition can form a finite time singularity in 2D or 3D. Thus, we provide a simple view of the problem studied by Castro, Cordoba, ... More
Hohenberg-Kohn Theorem for Coulomb Type SystemsAug 23 2011Density functional theory (DFT) has become a basic tool for the study of electronic structure of matter, in which the Hohenberg-Kohn theorem plays a fundamental role in the development of DFT. Unfortunately, the existing proofs are incomplete even incorrect; ... More
Motivic cohomology of quaternionic Shimura varieties and level raisingJan 07 2019Jan 29 2019We study the motivic cohomology of the special fiber of quaternionic Shimura varieties at a prime of good reduction. We exhibit classes in these motivic cohomology groups and use this to give an explicit geometric realization of level raising between ... More
Boltzmann distribution of free energies in a finite-connectivity spin-glass system and the cavity approachOct 06 2007At sufficiently low temperatures, the configurational phase space of a large spin-glass system breaks into many separated domains, each of which is referred to as a macroscopic state. The system is able to visit all spin configurations of the same macroscopic ... More
Temperature- and Force-Induced beta-Sheet Unfolding in an Exactly Solvable ModelDec 06 2001Mar 18 2002The stability of a $\beta$-sheeted conformation and its transition into a random coil are studied with a 2D lattice biopolymer model. At low temperature and low external force, the polymer folds back and forth on itself and forms a $\beta$-sheet. Our ... More
On the Performance of P2P Network: An Assortment MethodSep 12 2011P2P systems have grown dramatically in recent years. The most popular type of P2P systems are file sharing networks, which are used to share various types of content over the Internet. Due to the increase in popularity of P2P systems, the network performance ... More
Voronoi Summation Formulae on GL(n)Oct 13 2014Feb 03 2015We discover new Voronoi formulae for automorphic forms on GL($n$) for $n\geq 4$. There are $[n/2]$ different Voronoi formulae on GL($n$), which are Poisson summation formulae weighted by Fourier coefficients of the automorphic form with twists by some ... More
Spin Ordering and Quasiparticles in Spin Triplet Superconducting LiquidsJan 28 2002Jul 18 2002Spin ordering and its effect on low energy quasiparticles in a p-wave superconducting liquid are investigated. We show that there is a new 2D p-wave superconducting liquid where the ground state is rotation invariant. In quantum spin disordered liquids, ... More
Hidden topological order in $^{23}Na (F=1)$ Bose-Einstein CondensatesJul 12 2001Jul 13 2001We show the existence of a new hidden topological order in $^{23}Na$ (F=1) Bose-Einstein condensates (BEC) with antiferromagnetic interactions. Occurrence of this order is due to the confinement of hedgehogs in BEC where a spin Josephson effect takes ... More
Mott states under the influence of fermion-boson conversion: invasion of superfluidityMay 30 2005Jun 28 2005I study the influence of fermion-boson conversion near Feshbach resonances on Mott states of Cooper pairs and demonstrate possible invasion of superfluidity. The quantum dynamics of Fermi-Bose gases is studied using both an effective coupled $U(1)\otimes ... More
Spin-1/2 Collective Excitations in BEC of Interacting Spin-1 AtomsJun 07 2001We construct spin-1/2 collective excitations in BEC of interacting spin-1 atoms. These excitations exist in states with a maximal global degeneracy. The stability and energy of these objects are determined by interactions with spin fluctuations and are ... More
Spin correlation and Discrete symmetry in Spinor Bose-Einstein CondensatesFeb 21 2001Aug 25 2001We study spin correlations in Bose-Einstein condensates of spin 1 bosons with scatterings dominated by a total spin equal 2 channel. We show the low energy spin dynamics in the system can be mapped into an $o(n)$ nonlinear sigma model(NL$\sigma$M). $n=3$ ... More
On the Equivalence among Three Controllability Problems for a Networked SystemOct 11 2016A new proof is given for the mathematical equivalence among three $k$-sparse controllability problems of a networked system, which plays key roles in Olshevsky,2014, in the establishment of the NP-hardness of the associated minimal controllability problems ... More
Minimal Inputs/Outputs for Subsystems in a Networked SystemOct 07 2016Apr 13 2018Minimal input/output selection is investigated in this paper for each subsystem of a networked system. Some novel sufficient conditions are derived respectively for the controllability and observability of a networked system, as well as some necessary ... More
User Association with Maximizing Sum Energy Efficiency for Massive MIMO Enabled Heterogeneous Cellular NetworksJul 05 2016In this paper, we design an association scheme to maximize the sum energy efficiency for massive multiple-input and multiple-output (MIMO) enabled heterogeneous cellular networks (HCNs). Considering that the final formulated problem is in a sum-of-ratio ... More
Theoretical investigation of the four-layered self-doped high-T$_c$ superconductors: evidence of pair tunneling effectNov 28 2010Mar 29 2011Based on a four-layered self-doped $t-J$ type model and the slave-boson mean-field approach, we study theoretically the superconductivity in the electron-doped and hole-doped layers. The neighbor layers are coupled through both the single electron interlayer ... More
Global Regularity for the Two-dimensional Boussinesq Equations Without Diffusivity in Bounded DomainsOct 07 2015Mar 21 2018We address the well-posedness for the two-dimensional Boussinesq equations with zero diffusivity in bounded domains. We prove global in time regularity for rough initial data: both the initial velocity and temperature have $\epsilon$ fractional derivatives ... More
On the uniqueness conjecture for Markoff triplesOct 13 2000Nov 03 2000This paper has been withdrawn by author due to an error in the proof.
Criteria for Optimal Global Integrability of Hajłasz-Sobolev FunctionsApr 29 2010The author establishes some geometric criteria for a domain of ${\mathbb R}^n$ with $n\ge2$ to support a $(pn/(n-ps),\,p)_s$-Haj{\l}asz-Sobolev-Poincar\'e imbedding with $s\in(0,\,1]$ and $p\in(n/(n+s),\,n/s)$ or an $s$-Haj{\l}asz-Trudinger imbedding ... More
Circle patterns with obtuse exterior intersection anglesMar 06 2017Feb 09 2018Koebe-Andreev-Thurston theorem studies the existence and rigidity of circle patterns of a given combinatorial type and the given non-obtuse exterior intersection angles. By using the topological degree theory and variational principle, this paper derives ... More
A note on the degree-diameter problem for arc-transitive graphsDec 22 2013We give two lower bounds on the largest order of an arc-transitive graph of diameter two and a given degree.
A remark on Rickard complexesMay 21 2013In this paper, we characterize a Rickard complex, which induces a Rickard equivalence between the block algebras of a block $b$ and its Brauer correspondent and whose vertices have the same order as defect groups of the block $b$. The homology of such ... More
A note on abelian quotient categoriesApr 09 2019Let C be a triangulated category with a Serre functor S and X a non-zero contravariantly finite rigid subcategory of C. Then X is cluster tilting if and only if the quotient category C/X is abelian and S(X)=X[2]. As an application, this result generalizes ... More