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Results for "Choong-Seock Chang"

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Verification of the global gyrokinetic stellarator code XGC-S for linear ion temperature gradient driven modesMay 14 2019XGC (X-point Gyrokinetic Code) is a whole-volume, total-f gyrokinetic particle-in-cell code developed for modelling tokamaks. In recent work, XGC has been extended to model more general 3D toroidal magnetic configurations, such as stellarators. These ... More
Gyroaveraging operations using adaptive matrix operatorsFeb 26 2018Apr 20 2018A new adaptive scheme to be used in Particle-In-Cell codes for carrying out gyroaveraging operations with matrices is presented. This new scheme uses an intermediate velocity grid whose resolution is adapted to the local thermal Larmor radius. The charge ... More
Moment Preserving Constrained Resampling with Applications to Particle-in-Cell MethodsFeb 17 2017Oct 22 2017In simulations of partial differential equations using particle-in-cell (PIC) methods, it is often advantageous to resample the particle distribution function to increase simulation accuracy, reduce compute cost, and/or avoid numerical instabilities. ... More
A tight-coupling scheme sharing minimum information across a spatial interface between gyrokinetic turbulence codesJun 13 2018Jul 20 2018A new scheme that tightly couples kinetic turbulence codes across a spatial interface is introduced. This scheme evolves from considerations of competing strategies and down-selection. It is found that the use of a composite kinetic distribution function ... More
Verification of long wavelength electromagnetic modes with a gyrokinetic-fluid hybrid model in the XGC codeFeb 16 2017As an alternative option to kinetic electrons, the gyrokinetic total-f particle-in-cell (PIC) code XGC1 has been extended to the MHD/fluid type electromagnetic regime by combining gyrokinetic PIC ions with massless drift-fluid electrons analogous to Chen ... More
Discovering sterile Neutrinos ligther than $M_W$ at the LHCSep 20 2015Sep 27 2015We study the purely leptonic $W$ decays $W^+ \to e^+ \mu^- e^+ \nu_e$ and $W^+ \to e^+ e^+ \mu^- \bar \nu_\mu$ (or their charge conjugates) produced at the LHC, induced by sterile neutrinos with mass below $M_W$ in the intermediate state. While the first ... More
Be Stars in the Open Cluster NGC 6830Apr 08 2016We report the discovery of 2 new Be stars, and re-identify one known Be star in the open cluster NGC 6830. Eleven H-alpha emitters were discovered using the H-alpha imaging photometry of the Palomar Transient Factory Survey. Stellar membership of the ... More
Temperature Evolution of Itinerant Ferromagnetism in SrRuO3 Probed by Optical SpectroscopySep 04 2013The temperature ($T$) dependence of the optical conductivity spectra $\sigma(\omega)$ of a single crystal SrRuO$_3$ thin film is studied over a $T$ range from 5 to 450 K. We observed significant $T$ dependence of the spectral weights of the charge transfer ... More
Deep Learning Based Caching for Self-Driving Car in Multi-access Edge ComputingOct 03 2018Once self-driving car becomes a reality and passengers are no longer worry about it, they will need to find new ways of entertainment. However, retrieving entertainment contents at the Data Center (DC) can hinder content delivery service due to high delay ... More
Towards Efficient Detection of Small Near-Earth Asteroids Using the Zwicky Transient Facility (ZTF)Apr 21 2019We describe ZStreak, a semi-real-time pipeline specialized in detecting small, fast-moving near-Earth asteroids (NEAs) that is currently operating on the data from the newly-commissioned Zwicky Transient Facility (ZTF) survey. Based on a prototype originally ... More
eMBB-URLLC Resource Slicing: A Risk-Sensitive ApproachFeb 05 2019Ultra Reliable Low Latency Communication (URLLC) is a 5G New Radio (NR) application that requires strict reliability and latency. URLLC traffic is usually scheduled on top of the ongoing enhanced Mobile Broadband (eMBB) transmissions (i.e., puncturing ... More
Provenance-enabled Packet Path Tracing in the RPL-based Internet of ThingsNov 15 2018Dec 10 2018The interconnection of resource-constrained and globally accessible things with untrusted and unreliable Internet make them vulnerable to attacks including data forging, false data injection, and packet drop that affects applications with critical decision-making ... More
Community detection for networks with unipartite and bipartite structureJul 29 2013Sep 12 2014Finding community structures in networks is important in network science, technology, and applications. To date, most algorithms that aim to find community structures only focus either on unipartite or bipartite networks. A unipartite network consists ... More
Quantum Group and Quantum SymmetryAug 30 1995This is a self-contained review on the theory of quantum group and its applications to modern physics. A brief introduction is given to the Yang-Baxter equation in integrable quantum field theory and lattice statistical physics. The quantum group is primarily ... More
The Whitney extension theorem in high dimensionsAug 07 2015We prove a variant of the standard Whitney extension theorem for $\mathcal C^m(\mathbb R^n)$, in which the norm of the extension operator has polynomial growth in $n$ for fixed $m$.
Enhancing keV high harmonic signals generated by long-wave infrared lasersApr 23 2019It is demonstrated by single-atom simulations that X-ray signals in the 3.4 to 4 keV region from an 8 micron laser driven high harmonic generation can be increased by more than two orders of magnitude when a single-cycle pulse centered at 800 nm is added. ... More
A Simple $U(1)$ Gauge Theory Explanation of the Diphoton ExcessDec 20 2015Jan 07 2016The recent ATLAS and CMS diphoton resonance excesses are explored in a simple $U(1)$ gauge theory extension of the Standard Model where the resonance is the Higgs boson of the $U(1)$ symmetry breaking, $\phi$. This particle couples to exotic quarks which, ... More
On the arithmetic of twists of superelliptic curvesSep 18 2005Oct 13 2005In this paper, we consider a family of twists of a superelliptic curve over a global field, and obtain results on the distribution of the Mordell-Weil rank of these twists. Our results have applications to the distribution of the number of rational points. ... More
A "Littlest Higgs" Model with Custodial SU(2) SymmetryJun 03 2003Jan 07 2004In this note, a ``littlest higgs'' model is presented which has an approximate custodial SU(2) symmetry. The model is based on the coset space $SO(9)/(SO(5)\times SO(4))$. The light pseudo-goldstone bosons of the theory include a {\it single} higgs doublet ... More
InfraNotes: Inconspicuous Handwritten Trajectory Tracking for Lecture Note Recording with Infrared SensorsOct 07 2016Lecture notes are important for students to review and understand the key points in the class. Unfortunately, the students often miss or lose part of the lecture notes. In this paper, we design and implement an infrared sensor based system, InfraNotes, ... More
Integral representation of binary quadratic forms over rational function fieldsApr 06 2017For diophantine equations of the form ax^2+bxy+cy^2+g=0 over k[t], the ring of integers of rational funtional fields, we show that a condition with respect to the Artin reciprocity map, which we call the Artin condition, is the only obstruction to the ... More
The automorphism group functor of the N=4 Lie conformal superalgebraFeb 15 2013Aug 11 2014In this paper, we study the structure and representability of the automorphism group functor of the N=4 Lie conformal superalgebra over an algebraically closed field k of characteristic zero.
Skin cancer reorganization and classification with deep neural networkMar 01 2017As one kind of skin cancer, melanoma is very dangerous. Dermoscopy based early detection and recarbonization strategy is critical for melanoma therapy. However, well-trained dermatologists dominant the diagnostic accuracy. In order to solve this problem, ... More
A new Dirac-type equation for tachyonic neutrinosNov 10 2000Dec 30 2000Based on experimental evidences supporting the hypothesis that neutrinos might be tachyonic fermions, a new Dirac-type equation is proposed and a spin-1/2 tachyonic quantum theory is developed. The new Dirac-type equation provides a solution for the puzzle ... More
Modeling of Anisotropic Two-Dimensional Materials Monolayer HfS2 and Phosphorene MOSFETsMay 17 2015Ballistic transport characteristics of metal-oxide semiconductor field effect transistors (MOSFETs) based on anisotropic two-dimensional (2-D) materials monolayer HfS2 and phosphorene are explored through quantum transport simulations. We focus on the ... More
Kitaev models based on unitary quantum groupoidsSep 17 2013Jan 01 2014We establish a generalization of Kitaev models based on unitary quantum groupoids. In particular, when inputting a Kitaev-Kong quantum groupoid $H_\mathcal{C}$, we show that the ground state manifold of the generalized model is canonical isomorphic to ... More
Preliminary computation of the gap eigenmode of shear Alfvén waves on LAPDNov 29 2018Characterizing the gap eigenmode of shear Alfv\'{e}n waves (SAW) and its interaction with energetic ions is important to the success of magnetically confined fusion. Previous studies have reported an experimental observation of the spectral gap of SAW ... More
Alternate Derivation of Geometric Extended Kalman Filter by MEKF ApproachOct 11 2017This note is devoted to deriving the measurement update of the geometric extended Kalman filter using the multiplicative extended Kalman filtering approach, resulting in the attitude estimator referred as geometric multiplicative extended Kalman filter. ... More
Alfvénic gap eigenmode in a linear plasma with ending magnetic throatsNov 29 2018To guide the experimental design of a linear plasma device for studying the interaction between energetic ions and Alfv\'{e}nic gap eigenmode (AGE), this work computes AGE referring to fusion conditions in a ultra-long large plasma cylinder ended with ... More
Quantum ergodicity of Wigner induced spherical harmonicsDec 10 2015Apr 21 2016We show that a Wigner induced random orthonormal basis of spherical harmonics is almost surely quantum ergodic. Here, a random basis is identified with an element of the product probability space of unitary groups, each endowed with the measure induced ... More
Gamma factors of level zero supercuspidal representationsMar 27 2019We give an explicit formula for the twisted gamma factor for a pair of irreducible supercuspidal representations of level zero. We also obtain an explicit formula for the unramified base change of level zero supercuspidal representations.
Transition densities of one-dimensional Levy processesFeb 09 2015In this paper, we study the existence of the transition densities of one-dimensional L\'evy processes. Compared with past results, our results contain the L\'evy processes whose L\'evy symbols have logarithm behavior at infinity. Our results contain the ... More
Parity Violation and a Preferred FrameMar 31 2002Based on parity violation in the weak interaction and evidences from neutrino oscillation, a natural choice is that neutrinos may be spacelike particles with a tiny mass. To keep causality for spacelike particles, a kinematic time under a non-standard ... More
A proposed gravitodynamic theoryMar 18 1997This paper proposes a gravitodynamic theory because there are similarities between gravitational theory and electrodynamics. Based on Einstein's principle of equivalence, two coordinate conditions are proposed into the four-dimensional line element and ... More
Holography based on noncommutative geometry and the AdS/CFT correspondenceApr 14 1999Exponential regularization of orthogonal and Anti-de Sitter (AdS) space is presented based on noncommutative geometry. We show that an adequately adopted noncommutative deformation of geometry makes the holography of higher dimensional quantum theory ... More
On the Integral Representation of Binary Quadratic Forms and the Artin ConditionOct 16 2015For diophantine equations of the form ax^2+bxy+cy^2+g=0 over Z whose coefficients satisfy some hypotheses, we show that the Artin condition is the only obstruction to the local-global principle for integral solutions of the equation. Some concrete examples ... More
A New Proof of $\bf{Z_{Kup}=|Z_{Henn}|^2}$ for Semisimple Hopf AlgebrasApr 03 2015May 28 2016Hennings and Kuperberg defined quantum invariants $Z_{Henn}$ and $Z_{Kup}$ for closed oriented $3$-manifolds based on certain Hopf algebras, respectively. When the Hopf algebras are semisimple, it is shown that $Z_{Kup}=|Z_{Henn}|^2$. In this paper, we ... More
On Kalman-Like Finite Impulse Response FiltersJan 27 2015This note reveals an explicit relationship between two representative finite impulse response (FIR) filters, i.e. the newly derived and popularized Kalman-Like unbiased FIR filter (UFIR) and the receding horizon Kalman FIR filter (RHKF). It is pointed ... More
Particle Filtering for Attitude Estimation Using a Minimal Local-Error Representation: A RevisitNov 22 2014In this note, we have revisited the previously published paper "Particle Filtering for Attitude Estimation Using a Minimal Local-Error Representation". In the revisit, we point out that the quaternion particle filtering based on the local/global representation ... More
Finite-dimensional subalgebras of the Virasoro algebraAug 31 2014Nov 17 2014We determine all two-dimensional Lie subalgebras of the centreless Virasoro algebra and complete the characterization of all finite dimensional Lie subalgebras of the complex Virasoro algebra.
Loop cluster on the discrete circleNov 29 2013Jan 05 2015The loop clusters of a Poissonian ensemble of Markov loops on a finite or countable graph have been studied in \cite{Markovian-loop-clusters-on-graphs}. In the present article, we study the loop clusters associated with a rotation invariant nearest neighbor ... More
Joint source-channel with side information coding error exponentsJan 23 2009In this paper, we study the upper and the lower bounds on the joint source-channel coding error exponent with decoder side-information. The results in the paper are non-trivial extensions of the Csiszar's classical paper [5]. Unlike the joint source-channel ... More
Nonstandard Higgs DecaysAug 01 2008The crucial search for the Higgs boson at future colliders is capable of discovering the Standard Model Higgs, but is not guaranteed to discover a Higgs that decays nonstandardly. Such new physics is motivated by many aspects; from experiment, by the ... More
Toral stabilizers of restricted Lie algebrasAug 07 2016Aug 18 2016This paper investigates the toral stabilizer of a finite-dimensional restricted Lie algebra $(\mathfrak{g},[p])$, defined over an algebraically closed field $k$ of positive characteristic. We compute the group of toral stabilizers of some simple Lie algebras ... More
A Dirac-type equation for spacelike neutrinosMar 21 2001Based on experimental evidences supporting the hypothesis that neutrinos might be spacelike particles, a new Dirac-type equation is proposed and a spin-1/2 spacelike quantum theory is developed. The new Dirac-type equation provides a solution for the ... More
Challenges in Hyperon DecaysNov 13 2000Nov 28 2000We give an personal overview of some of the unsolved problems related to hyperon decays. We cover nonleptonic decays, radiative decays and magnetic moments. Some of the theoretical issues are also touched upon.
Probe a family non-universal Z' boson effects in B(s)-> phi mu(+) mu(-)decayJan 06 2011Motivated by the recent measurement on ${\cal B}(\bar{B}_s\to \phi \mu^+\mu^-)$ by CDF collaboration, we study the effects of a family non-universal $Z^{\prime}$ boson on rare semileptonic $\bar{B}_s \to \phi\mu^+\mu^-$ decay. In our evaluations, we analyze ... More
Semi-Analytic Method for SINS Attitude and Parameters Online EstimationJan 16 2018In this note, the attitude and inertial sensors drift biases estimation for Strapdown inertial navigation system is investigated. A semi-analytic method is proposed, which contains two interlaced solution procedures. Specifically, the attitude encoding ... More
On the limit of spectral gap formation via Bragg's reflectionNov 29 2018Although it is well recognized that waves propagating in periodic media have forbidden gaps in the continuous spectrum, it is still yet unknown about the minimum number and depth of periodic modulations for clear spectral formation. This limit is explored ... More
Explorations into the inertial and integral scales of homogeneous axisymmetric turbulenceJan 31 2012A flow generator is described in which homogeneous axisymmetric turbulent air flows with varying and fully controllable degrees of anisotropy, including the much studied isotropic case, are generated by the combined agitations produced by 32 acoustic ... More
The Effectiveness of the Kozai Mechanism in the Galactic CentreNov 05 2008I examine the effectiveness of Kozai oscillations in the centres of galaxies and in particular the Galactic centre using standard techniques from celestial mechanics. In particular, I study the effects of a stellar bulge potential and general relativity ... More
Boundary integral operator for the fractional Laplace equation in a bounded Lipschitz domainJul 05 2011We study the boundary integral operator induced from fractional Laplace equation in a bounded Lipschitz domain. As an application, we study the boundary value problem of a fractional Laplace equation.
Boundary integral operator for the fractional Laplacian in the bounded smooth domainNov 18 2014We study the boundary integral operator induced from the fractional Laplace equation in a bounded smooth domain. For $1/2 < \alpha? < 1$, we show the bijectivity of the boundary integral operator $S_{2\alpha} : L^p(\partial \Omega) \rightarrow H^{2\alpha-1}_p ... More
Parity Violation and Neutrino MassAug 26 2002Besides the fact of parity violation in weak interactions, based on evidences from neutrino oscillation and tritium beta decay, a natural conjecture is that neutrinos may be spacelike particles with a tiny proper mass. A Dirac-type equation for spacelike ... More
On the Bernoulli Automorphism of Reversible Linear Cellular AutomataMar 20 2015Sep 22 2015This investigation studies the ergodic properties of reversible linear cellular automata over $\mathbb{Z}_m$ for $m \in \mathbb{N}$. We show that a reversible linear cellular automaton is either a Bernoulli automorphism or non-ergodic. This gives an affirmative ... More
Interface Selection for Power Management in UMTS/WLAN Overlaying NetworkOct 05 2018The multiple choices of access networks offer different opportunities and overcome the limitations of other technologies. Optimal selection of interface is a big challenge for multiple interfaces supported mobile terminals to make a seamless handover ... More
How to Observe the Interference Effects of Top quark polarizations at TevatronJun 24 1996Using a simple analytic expression for $q \bar{q}, g g \rightarrow t \bar{t} \rightarrow b W^+ \bar{b} W^- \rightarrow b \bar{l} \nu_l \bar{b} l' \bar{\nu_{l'}}$ with the interference effects due to the polarizations of the $t$ and $\bar{t}$, we demonstrate ... More
Sznajd sociophysics model on a triangular lattice: ferro and antiferromagnetic opinionsSep 11 2001The Sznajd sociophysics model is generalized on the triangular lattice with pure antiferromagnetic opinion and also with both ferromagnetic and antiferromagnetic opinions. The slogan of the trade union "united we stand, divided we fall" can be realized ... More
A Near-optimal Algorithm for Edge Connectivity-based Hierarchical Graph DecompositionNov 25 2017Driven by many applications in graph analytics, the problem of computing $k$-edge connected components ($k$-ECCs) of a graph $G$ for a user-given $k$ has been extensively studied recently. In this paper, we investigate the problem of constructing the ... More
The impact of magnetic geometry on wave modes in cylindrical plasmasMar 18 2015Both space and laboratory plasmas can be associated with static magnetic field, and the field geometry varies from uniform to non-uniform. This thesis investigates the impact of magnetic geometry on wave modes in cylindrical plasmas. The cylindrical configuration ... More
Worst-Case Analysis for a Leader-follower Partially Observable Stochastic GameJan 06 2019This paper studies a leader-follower partially observable stochastic game where (i) the two agents are non-cooperative, and (ii) the follower's objective is unknown to the leader and/or the follower is irrational. We determine the leader's optimal value ... More
Identifiability of Electrical and Heat Transfer Parameters Using Coupled Boundary MeasurementsMar 05 2016In this paper, we show that a hybrid method using coupled boundary measurements can determine electrical conductivity, thermal conductivity, and the product of heat capacity and heat density within a bounded domain on the plane uniquely up to a boundary-fixing ... More
Supercritical loop percolation on $\mathbb{Z}^d$ for $d\geq 3$Apr 29 2015In this paper, we are interested in the loop cluster model on $\mathbb{Z}^d$ for $d\geq 3$. It is a long range model with two parameters $\alpha$ and $\kappa$, where the non-negative parameter $\alpha$ measures the amount of loops, and $\kappa$ plays ... More
Note on the rank of quadratic twists of Mordell equationsSep 30 200514H52 : Elliptic curves Let E be the elliptic curve given by a Mordell equation y^2=x^3-A where A is an integer. For certain A, we use Stoll's formula to compute a lower bound for the proportion of square-free integers D up to X such that the Mordell-Weil ... More
Nonexistence of generalized bent functions and the quadratic norm form equationsApr 04 2018We obtain the nonexistence of generalized bent functions (GBFs) from (\ZZ/t\ZZ)^n to \ZZ/t\ZZ (called type [n,t]), for a large new class. Specifically, by showing certain quadratic norm form equations have no integral points, we obtain the universal nonexistence ... More
On the Non-existence of certain classes of perfect p-ary sequences and perfect almost p-ary sequencesDec 17 2016We obtain new non-existence results of perfect p-ary sequences with period n (called type $[p, n]$). The first case is a class with type [p\equiv5\pmod 8,p^aqn']. The second case contains five types [p\equiv3\pmod 4,p^aq^ln'] for certain $p, q$ and $l$. ... More
A Dirichlet problem of the fractional Laplace equation in the bounded Lipschitz domainMay 22 2012In this paper, we study a Dirichlet problem of a fractional Laplace equation in a bounded Lipschitz domain in $ \R, n \geq 2$. Our main result is that for the given data $F \in \dot H^s(\Om^c), 0 < s<1$, we find the function which satisfies that $\De^s ... More
Properties of parabolic Sobolev and parabolic Besov spacesAug 02 2011In this paper, we characterize parabolic Besov and parabolic Sobolev spaces in ${\bf R}^{n+1}$ and ${\bf R}^{n+1}_T, \,\, T > 0$. We also, study the relation between parabolic Besov spaces in ${\bf R}^{n}_T, \,\, T > 0$ and standard Besov space in $\R$. ... More
Fundamental thickness limit of itinerant ferromagnetic SrRuO$_3$ thin filmsMar 02 2009Jul 07 2009We report on a fundamental thickness limit of the itinerant ferromagnetic oxide SrRuO$_3$ that might arise from the orbital-selective quantum confinement effects. Experimentally, SrRuO$_3$ films remain metallic even for a thickness of 2 unit cells (uc), ... More
On the Observation of Top Spin Correlation Effect at TevatronDec 25 1995We propose to observe the top spin correlation effect at Tevatron through the measurement of the correlated asymmetries of the charged lepton momenta using the dilepton decay events of top and anti-top quark pairs. The possibility of reconstructing the ... More
The Effect of Top Quark Polarization at Hadronic CollidersAug 23 1995We derive a simple analytic expression for q \bar{q}, g g -> t \bar{t} -> b W^+ \bar{b} W^- -> b \bar{l} \nu_l \bar{b} l' \bar{\nu_{l'}} for on shell intermediate states with the interference effects due to the polarizations of the t and \bar{t}. We then ... More
Enhancement of Energy-Based Swing-Up Controller via Entropy SearchApr 02 2019Apr 03 2019An energy based approach for stabilizing a mechanical system has offered a simple yet powerful control scheme. However, since it does not impose such strong constraints on parameter space of the controller, finding appropriate parameter values for an ... More
Regularity of quasi-n-harmonic mappings into NPC spacesSep 13 2017Jan 02 2018We prove local Holder continuity of quasi-n-harmonic mappings from Euclidean domains into metric spaces with non-positive curvature in the sense of Alexandrov. We also obtain global Holder continuity of such mappings from bounded Lipschitz domains.
Palomar Transient Factory and RR Lyrae: Metallicity-Light Curve Relation Based on ab-Type RR Lyrae in Kepler FieldDec 11 2016The wide-field synoptic sky surveys, known as the Palomar Transient Factory (PTF) and the intermediate Palomar Transient Factory (iPTF), will accumulate a large number of known and new RR Lyrae. These RR Lyrae are good tracers to study the substructure ... More
Electronic Structure of the Kitaev Material $α$-$\textrm{RuCl}_3$ Probed by Photoemission and Inverse Photoemission SpectroscopiesAug 22 2016Recently, $\alpha$-$\textrm{RuCl}_3$ has attracted much attention as a possible material realization of the honeycomb Kitaev model, which may stabilize a quantum-spin-liquid state. Compared to extensive studies on its magnetic properties, there is still ... More
Reconstruction of Cosmic and Beam-Halo Muons with the CMS DetectorOct 21 2008Oct 21 2008The powerful muon and tracker systems of the CMS detector together with dedicated reconstruction software allow precise and efficient measurement of muon tracks originating from proton-proton collisions. The standard muon reconstruction algorithms, however, ... More
A Unified Microscopic-Macroscopic Monte Carlo Simulation of Gas-Grain Chemistry in Cold Dense Interstellar CloudsSep 25 2012For the first time, we report a unified microscopic-macroscopic Monte Carlo simulation of gas-grain chemistry in cold interstellar clouds in which both the gas-phase and the grain surface chemistry are simulated by a stochastic technique. The surface ... More
A Charge-Conjugation-Invariance Constrained Pomeron-Quark CouplingJan 20 2005The commonly used $\gamma_{\mu}} Pomeron-quark coupling changes its sign under charge conjugation, in contradiction to the property of Pomeron. I show that the Pomeron-quark coupling is tensorial and is invariant under the charge conjugation.
Target Density Normalization for Markov Chain Monte Carlo AlgorithmsOct 27 2014Oct 28 2014Techniques for evaluating the normalization integral of the target density for Markov Chain Monte Carlo algorithms are described and tested numerically. It is assumed that the Markov Chain algorithm has converged to the target distribution and produced ... More
Blow-up in reaction-diffusion systems under Robin boundary conditionsSep 09 2015In this paper we apply the differential inequality technique of Payne {\it et. al} \cite{Payne&SchaeferRobin08} to show that a reaction-diffusion system admits blow-up solutions, and to determine an upper bound for the blow-up time. For a particular nonlinearity, ... More
Rokhlin dimension of Z^m actions on simple C*-algebrasAug 03 2016We study Rokhlin dimension of Z^m-actions on simple separable stably finite nuclear C*-algebras. We prove that under suitable assumptions, a strongly outer Z^m-action has finite Rokhlin dimension. This extends the known result for automorphisms. As an ... More
Surface and bulk melting of small metal clustersDec 16 2006We present an analytical solution to the two-parabola Landau model, applied to melting of metal particles with sizes in the nanoscale range. The results provide an analytical understanding of the recently observed pseudo-crystalline phase of nanoscale ... More
Monte Carlo Algorithm for Simulating Reversible Aggregation of Multisite ParticlesOct 02 2010Sep 26 2011We present an efficient and exact Monte Carlo algorithm to simulate reversible aggregation of particles with dedicated binding sites. This method introduces a novel data structure of dynamic bond tree to record clusters and sequences of bond formations. ... More
Modified Newton's gravity in Finsler Space as a possible alternative to dark matter hypothesisJun 13 2008Sep 27 2008A modified Newton's gravity is obtained as the weak field approximation of the Einstein's equation in Finsler space. It is found that a specified Finsler structure makes the modified Newton's gravity equivalent to the modified Newtonian dynamics (MOND). ... More
Inverse Lax-Wendroff method for boundary conditions of Boltzmann type modelsSep 14 2012In this paper we present a new algorithm based on a Cartesian mesh for the numerical approximation of kinetic models on complex geometry boundary. Due to the high dimensional property, numerical algorithms based on unstructured meshes for a complex geometry ... More
Is there a fundamental acceleration scale in galaxies?Dec 12 2018Milgrom's modified Newtonian dynamics (MOND) can explain well the mass discrepancy problem in galaxy without invoking dark matter. The MOND theory predicts a universal constant acceleration scale in galaxy, below which the Newtonian dynamics is no longer ... More
Learning Representations of Emotional Speech with Deep Convolutional Generative Adversarial NetworksApr 22 2017Automatically assessing emotional valence in human speech has historically been a difficult task for machine learning algorithms. The subtle changes in the voice of the speaker that are indicative of positive or negative emotional states are often "overshadowed" ... More
Some Consequences of the Hypothesis of Minimal LengthsMay 07 2004Talk presented at the 3rd International Symposium on Quantum Theory and Symmetries, September 13, 2003, University of Cincinnati, OH. Dedicated to the memory of Freydoon Mansouri.
Latent Variable Modeling for Generative Concept Representations and Deep Generative ModelsDec 26 2018Latent representations are the essence of deep generative models and determine their usefulness and power. For latent representations to be useful as generative concept representations, their latent space must support latent space interpolation, attribute ... More
Theoretical Study of Phosphorene Tunneling Field Effect TransistorsFeb 14 2015In this work, device performances of tunneling field effect transistors (TFETs) based on phosphorene are explored via self-consistent atomistic quantum transport simulations. Phosphorene is an ultra-thin two-dimensional (2-D) material with a direct band ... More
Arithmetic progressions in multiplicative groups of finite fieldsAug 18 2016Nov 17 2016Let $G$ be a multiplicative subgroup of the prime field $\mathbb F_p$ of size $|G|> p^{1-\kappa}$ and $r$ an arbitrarily fixed positive integer. Assuming $\kappa=\kappa(r)>0$ and $p$ large enough, it is shown that any proportional subset $A\subset G$ ... More
Numerical Simulations to the Vlasov-Poisson System with a Strong Magnetic FieldMay 28 2018In this paper, we present an efficient Particle-In-Cell algorithm for the simulation of the three dimensional Vlasov-Poisson system in the presence of a strong external magnetic field. When the intensity of the magnetic field is sufficiently large and ... More
Nucleon partonic spin structure to be explored by the unpolarized Drell-Yan program of COMPASS experiment at CERNJan 12 2015The observation of the violation of Lam-Tung relation in the $\pi N$ Drell-Yan process triggered many theoretical speculations. The TMD Boer-Mulders functions characterizing the correlation of transverse momentum and transverse spin for partons in unpolarized ... More
A fast Newton-Shamanskii iteration for M/G/1-type and GI/M/1-type Markov chainsAug 26 2015For the nonlinear matrix equations arising in the analysis of M/G/1-type and GI/M/1-type Markov chains, the minimal nonnegative solution $G$ or $R$ can be found by Newton-like methods. Recently a fast Newton's iteration is proposed in \cite{Houdt2}. We ... More
Algebraic Shape Invariant Potentials as the Generalized Deformed OscillatorJun 01 2009Within the framework of supersymmetric quantum mechanics, we study the simplified version of potential algebra of shape invariance condition in k steps, where k is an arbitrary positive integer. The associated potential algebra is found to be equivalent ... More
Systemic Risk and the Dependence StructuresSep 10 2018We propose a dynamic model of dependence structure between financial institutions within a financial system and we construct measures for dependence and financial instability. Employing Markov structures of joint credit migrations, our model allows for ... More
The efficiency of community detection by most similar node pairsJan 11 2018Community analysis is an important way to ascertain whether or not a complex system consists of sub-structures with different properties. In this paper, we give a two level community structure analysis for the SSCI journal system by most similar co-citation ... More
Hardness of RNA Folding Problem with Four SymbolsNov 15 2015Mar 22 2018An RNA sequence is a string composed of four types of nucleotides, $A, C, G$, and $U$. The goal of the RNA folding problem is to find a maximum cardinality set of crossing-free pairs of the form $\{A,U\}$ or $\{C,G\}$ in a given RNA sequence. The problem ... More
Combinatorial constructions for optimal two-dimensional optical orthogonal codes with $λ$ = 2Dec 29 2013In this paper, we are concerned about optimal two-dimensional optical orthogonal codes with $\lambda$ = 2. Some combinatorial constructions are presented and many infinite families of optimal two-dimensional optical orthogonal codes with weight 4 and ... More
Equation of State of Dark Matter after Planck DataOct 06 2013Dec 10 2013In this paper, we loosen the zero equation of state of dark matter to a constant $w_{dm}$. By using the currently available cosmic observations which include the type-Ia supernovae, the baryon acoustic oscillation, the WiggleZ measurements of matter power ... More