Results for "Xinzhong Er"

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Gravitational lensing properties of isothermal universal halo profileDec 17 2012N-body simulations predict that dark matter halos with different mass scales are described by a universal model, the Navarro-Frenk-White (NFW) density profiles. As a consequence of baryonic cooling effects, the halos will become more concentrated, and ... More
Measurement of differential magnificationAug 11 2014In gravitational lensing, the magnification effect changes the luminosity and size of a background galaxy. If the image sizes are not small compared to the scale over which the magnification and shear vary, higher-order distortions occur which are termed ... More
Estimate of dark halo ellipticity by lensing flexionSep 16 2010Aims. The predictions of the ellipticity of the dark matter halos from models of structure formation are notoriously difficult to test with observations. A direct measurement would give important constraints on the formation of galaxies, and its effect ... More
Effects of plasma on gravitational lensingOct 22 2013Nov 06 2013We study gravitational lensing when plasma surrounds the lens. An extra deflection angle is induced by the plasma in addition to the deflection generated by gravity. An inhomogeneous plasma distribution generates a greater effect than a homogeneous one, ... More
Increasing the Lensing Figure of Merit through Higher Order Convergence MomentsFeb 08 2018The unprecedented quality, the increased dataset, and the wide area of ongoing and near future weak lensing surveys allows to move beyond the standard two points statistics thus making worthwhile to investigate higher order probes. As an interesting step ... More
Cosmic tidal reconstructionNov 15 2015May 09 2016The gravitational coupling of a long-wavelength tidal field with small-scale density fluctuations leads to anisotropic distortions of the locally measured small-scale matter correlation function. Since the local correlation function is known to be statistically ... More
Estimation of halo ellipticity using spin-3 flexionSep 14 2012Estimating the ellipticity of dark matter haloes at the galaxy or galaxy-cluster scale can provide important constraints on the formation of galaxies or clusters, as well as on the nature of dark matter. We show in this paper that the spin-3 gravitational ... More
Weak lensing goes bananas: What flexion really measuresSep 07 2007In weak gravitational lensing, the image distortion caused by shear measures the projected tidal gravitational field of the deflecting mass distribution. To lowest order, the shear is proportional to the mean image ellipticity. If the image sizes are ... More
Mass reconstruction by gravitational shear and flexionAug 18 2010Galaxy clusters are considered as excellent probes for cosmology. For that purpose, their mass needs to be measured and their structural properties needs to be understood. We propose a method for galaxy cluster mass reconstruction which combines information ... More
Measurement of halo properties with weak lensing shear and flexionDec 20 2011We constrain properties of cluster haloes by performing likelihood analysis using lensing shear and flexion data. We test our analysis using two mock cluster haloes: an isothermal ellipsoid (SIE) model and a more realistic elliptical Navarro-Frenk-White ... More
Biases in physical parameter estimates through differential lensing magnificationMar 21 2013We study the lensing magnification effect on background galaxies. Differential magnification due to different magnifications of different source regions of a galaxy will change the lensed composite spectra. The derived properties of the background galaxies ... More
An exact analytic spectrum of relic gravitational waves in an accelerating universeApr 21 2006Nov 28 2008An exact analytic calculation is presented for the spectrum of relic gravitational waves in the scenario of accelerating Universe $\Omega_{\Lambda}+\Omega_m = 1$. The spectrum formula contains explicitly the parameters of acceleration, inflation, reheating, ... More
Gravitational lensing effects on sub-millimetre galaxy countsJan 03 2013We study the effects on the number counts of sub-millimetre galaxies due to gravitational lensing. We explore the effects on the magnification cross section due to halo density profiles, ellipticity and cosmological parameter (the power-spectrum normalisation ... More
Estimate of halo ellipticity as a function of radius with flexionsJul 07 2011The cold dark matter theory predicts triaxial dark matter haloes. The radial distribution of halo ellipticity depends on baryonic processes and the nature of dark matter particles (collisionless or collisional). Here we show that we can use lensing flexion ... More
The Radiative Stress TensorMar 31 2000We use the transfer equation in relativistic form to develop an expansion of the one-photon distribution for a medium with constant photon mean free path, $\epsilon$. The resulting radiative viscosity tensor may be expressed either as a simple integral ... More
Causal Relativistic Fluid DynamicsJul 01 2011We derive causal relativistic fluid dynamical equations from the relaxation model of kinetic theory as in a procedure previously applied in the case of non-relativistic rarefied gases. By treating space and time on an equal footing and avoiding the iterative ... More
Improving lensing cluster mass estimate with flexionJul 20 2016Gravitational lensing has long been considered as a valuable tool to determine the total mass of galaxy clusters. The shear profile as inferred from the statistics of ellipticity of background galaxies allows to probe the cluster intermediate and outer ... More
Large Size Scatter of Passively Evolving Lensed Galaxies at z~2 in CLASHDec 30 2012In a systematic search over 11 cluster fields from Cluster Lensing And Supernova survey with Hubble (CLASH) we identify ten passively evolving massive galaxies at redshift z~2.We derive the stellar properties of these galaxies using HST WFC3/ACS multiband ... More
An Efficient Watermarking Algorithm to Improve Payload and Robustness without Affecting Image Perceptual QualityApr 26 2010Capacity, Robustness, & Perceptual quality of watermark data are very important issues to be considered. A lot of research is going on to increase these parameters for watermarking of the digital images, as there is always a tradeoff among them. . In ... More
Effect of Crosstalk on Permutation in Optical Multistage Interconnection NetworksApr 26 2010Optical MINs hold great promise and have advantages over their electronic networks.they also hold their own challenges. More research has been done on Electronic Multistage Interconnection Networks, (EMINs) but these days optical communication is a good ... More
Mobile Zigbee Sensor NetworksApr 26 2010OPNET Modeler accelerates network R&D and improves product quality through high-fidelity modeling and scalable simulation. It provides a virtual environment for designing protocols and devices, and for testing and demonstrating designs in realistic scenarios ... More
A Continuum Description of Rarefied Gas Dynamics (III)--- The Structures of Shock WavesMay 20 2001We use the one-dimensional steady version of the equations derived in paper I to compute the structure of shock waves. The agreement with experiment is good, especially when we retain the experimental value of the Prandtl number adopted in II.
A Continuum Description of Rarefied Gas Dynamics (I)--- Derivation From Kinetic TheoryMay 20 2001We describe an asymptotic procedure for deriving continuum equations from the kinetic theory of a simple gas. As in the works of Hilbert, of Chapman and of Enskog, we expand in the mean flight time of the constituent particles of the gas, but we do not ... More
The Advantage of Rightmost Ordering for gamma5 in Dimensional RegularizationMay 10 2009We propose a gamma5 scheme in dimensional regularization by analytically continuing the dimension after all the gamma5 matrices have been moved to the rightmost position. All Feynman amplitudes corresponding to diagrams with no fermion loops regulated ... More
An Immersive Telepresence System using RGB-D Sensors and Head Mounted DisplayNov 21 2015We present a tele-immersive system that enables people to interact with each other in a virtual world using body gestures in addition to verbal communication. Beyond the obvious applications, including general online conversations and gaming, we hypothesize ... More
Gauge Invariant Treatment of $γ_{5}$ in the Scheme of 't Hooft and VeltmanMay 11 2009Nov 29 2010We propose moving all the $\gamma_{5}$ matrices to the rightmost position before continuing the dimension, and show that this simple prescription will enable the dimension regularization scheme proposed by 't Hooft and Veltman to be consistent with gauge ... More
Maintaining Gauge Symmetry in Renormalizing Chiral Gauge TheoriesDec 16 2010It is known that the $\gamma_{5}$ scheme of Breitenlohner and Maison (BM) in dimensional regularization requires finite counter-term renormalization to restore gauge symmetry and implementing this finite renormalization in practical calculation is a daunting ... More
Muon Anomalous Magnetic Moment and Gauge Symmetry in the Standard ModelOct 24 2014No gauge invariant regularization is available for the perturbative calculation of the standard model. One has to add finite counter terms to restore gauge symmetry for the renormalized amplitudes. The muon anomalous magnetic moment can be accurately ... More
Properties of nucleon in nuclear matter: once moreJan 08 2014May 09 2014We calculate the mass and residue of the nucleon in nuclear matter in the framework of QCD sum rules using the nucleon's interpolating current with an arbitrary mixing parameter. We evaluate the effects of the nuclear medium on these quantities and compare ... More
X-ray Emission from Transient Jet Model in Black Hole BinariesMay 24 2011May 16 2012While the non-thermal radio through at least near-infrared emission in the hard state in X-ray binaries (XRBs) is known to originate in jets, the source of the non-thermal X-ray component is still uncertain. We introduce a new model for this emission, ... More
The high energy tail of gamma-ray burst 941017: Comptonization of synchrotron self absorbed photonsOct 29 2003Mar 01 2004The recent detection of an unusually hard spectral component in GRB941017 extending to $\ge200$ MeV is hard to explain as a synchrotron emission from shock-accelerated electrons. It was argued to imply acceleration of protons to ultra-high energy. We ... More
Quasi-blackbody component and radiative efficiency of the prompt emission of gamma-ray burstsNov 25 2008Jun 26 2009We perform time-resolved spectroscopy on the prompt emission in gamma-ray bursts (GRBs) and identify a thermal, photospheric component peaking at a temperature of a few hundreds keV. This peak does not necessarily coincide with the broad band (keV-GeV) ... More
GeneZip: A software package for storage-efficient processing of genotype dataAug 09 2013Nov 17 2013Genome wide association studies directly assay 10^6 single nucleotide polymorphisms (SNPs) across a study cohort. Probabilistic estimation of additional sites by genotype imputation can increase this set of variants by 10- to 40-fold. Even with modest ... More
Constraining Sources of Ultra High Energy Cosmic Rays Using High Energy Observations with the Fermi SatelliteNov 16 2011Feb 09 2012We analyze the conditions that enable acceleration of particles to ultra-high energies, ~10^{20} eV (UHECRs). We show that broad band photon data recently provided by WMAP, ISOCAM, Swift and Fermi satellites, yield constraints on the ability of active ... More
Extended Role Based Access Control with Blob Service on CloudNov 30 2013Role-based access control (RBAC) models have generated a great interest in the security community as a powerful and generalized approach to security management and ability to model organizational structure and their capability to reduce administrative ... More
On the role of the magnetic field on jet emission in X-ray binariesAug 17 2009Radio and X-ray fluxes of accreting black holes in their hard state are known to correlate over several orders of magnitude. This correlation however shows a large scatter: black hole candidates with very similar X-ray luminosity, spectral energy distribution ... More
Parallel Genetic Algorithm to Solve Traveling Salesman Problem on MapReduce Framework using Hadoop ClusterJan 24 2014Traveling Salesman Problem (TSP) is one of the most common studied problems in combinatorial optimization. Given the list of cities and distances between them, the problem is to find the shortest tour possible which visits all the cities in list exactly ... More
A novel progressive learning technique for multi-class classificationSep 01 2016In this paper, a progressive learning technique for multi-class classification is proposed. This newly developed learning technique is independent of the number of class constraints and it can learn new classes while still retaining the knowledge of previous ... More
Mode Locking At and Below the CW ThresholdJan 02 2013We explore experimentally a new regime of operation for mode locking in a Ti:Sapphire laser with enhanced Kerr nonlinearity, where the threshold for pulsed operation is lowered below the threshold for continuous-wave (CW) operation. Even though a CW solution ... More
A Theory of Mulicolor Black Body Emission from Relativistically Expanding PlasmasAug 26 2010We consider the emission of photons from the inner parts of a relativistically expanding plasma outflow, characterized by a constant Lorentz factor, Gamma. Photons that are injected in regions of high optical depth are advected with the flow until they ... More
Acceleration of trapped particles and beamsMar 29 2011Jul 30 2011The dynamics of a quantum particle bound by an accelerating delta-functional potential is investigated. Three cases are considered, using the reference frame moving along with the {\delta}-function, in which the acceleration is converted into the additional ... More
Prompt GRB spectra: detailed calculations and the effect of pair productionNov 11 2003Jun 01 2004We present detailed calculations of the prompt spectrum of gamma-ray bursts (GRBs) predicted within the fireball model framework, where emission is due to internal shocks in an expanding relativistic wind. Our time dependent numerical model describes ... More
A Review of Cavity Design for Kerr Lens Mode-Locked Solid-State LasersJan 06 2015We provide a critical review of the fundamental concepts of Kerr lens mode-locking (KLM), along with a detailed description of the experimental considerations involved in the realization of a mode-locked oscillator. In addition, we review recent developments ... More
Observations, theory and implications of thermal emission from gamma-ray burstsMar 12 2010Recent analyses show evidence for a thermal emission component that accompanies the non-thermal emission during the prompt phase of GRBs. First, we show the evidence for the existence of this component; Second, we show that this component is naturally ... More
Abelian regular coverings of the quaternion hypermapSep 03 2015A hypermap is an embedding of a connected hypergraph into an orientable closed surface. A covering between hypermaps is a homomorphism between the embedded hypergraphs which extends to an orientation-preserving covering of the supporting surfaces. A covering ... More
Photospheric Emission in Gamma-Ray BurstsMar 16 2016A major breakthrough in our understanding of gamma-ray bursts (GRB) prompt emission physics occurred in the last few years, with the realization that a thermal component accompanies the over-all non-thermal prompt spectra. This thermal part is important ... More
Efficient simulation of wave-packet dynamics on multiple coupled potential surfaces with split potential propagationMar 23 2016We present a simple method to expedite simulation of quantum wave-packet dynamics by more than a factor of $2$ with the Strang split-operator propagation. Dynamics of quantum wave-packets are often evaluated using the the \emph{Strang} split-step propagation, ... More
Multi-Label Classification Method Based on Extreme Learning MachinesAug 30 2016In this paper, an Extreme Learning Machine (ELM) based technique for Multi-label classification problems is proposed and discussed. In multi-label classification, each of the input data samples belongs to one or more than one class labels. The traditional ... More
Rare events in stochastic populations under bursty reproductionAug 06 2016Recently, a first step was made by the authors towards a systematic investigation of the effect of reaction-step-size noise - uncertainty in the step size of the reaction - on the dynamics of stochastic populations. This was done by investigating the ... More
A Model for Emission from Jets in X-ray Binaries: Consequences of a Single Acceleration EpisodeFeb 17 2009Apr 13 2009There are strong evidence for powerful jets in the low/hard state of black-hole X-ray binaries (BHXRBs). Here, we present a model in which electrons are accelerated once at the base of the jet, and are cooled by synchrotron emission and possible adiabatic ... More
Time dependent numerical model for the emission of radiation from relativistic plasmaSep 22 2004Apr 15 2005We describe a numerical model constructed for the study of the emission of radiation from relativistic plasma under conditions characteristic, e.g., to gamma-ray bursts (GRB's) and active galactic nuclei (AGN's). The model solves self consistently the ... More
High energy photon emission in the early afterglow of GRB'sJul 05 2004Jul 26 2005We consider the emission within the fireball model framework of very high energy, ~1 GeV to >1 TeV photons, on a minute time scale, during the onset of fireball deceleration due to interaction with surrounding medium. Our time dependent numerical model ... More
Detection of high-power two-mode squeezing by sum-frequency generationSep 12 2009Aug 14 2012We introduce sum-frequency generation (SFG) as an effective physical two-photon detector for high power two-mode squeezed coherent states with arbitrary frequency separation, as produced by parametric oscillators well above the threshold. Using a formalism ... More
Mass Effect on Axial Charge DynamicsFeb 12 2016Jun 04 2016We studied effect of finite quark mass on the dynamics of axial charge using the D3/D7 model in holography. The mass term in axial anomaly equation affects both the fluctuation (generation) and dissipation of axial charge. We studied the dependence of ... More
Scalar and vector self-energies of heavy baryons in nuclear mediumMay 18 2016The in-medium sum rules are employed to calculate the shifts in the mass and residue as well as the scalar and vector self-energies of the heavy $\Lambda_Q, \Sigma_Q$ and $\Xi_Q$ baryons, with Q being $b$ or $c$ quark. The maximum shift in mass due to ... More
Dispersion Compensation using a Prism-pairNov 02 2014Jul 21 2016A simple and intuitive formulation is reviewed for the Brewster prism-pair - A most common component in spectroscopy-oriented experiments using ultrashort pulses. This review aims to provide students and beginners in the field of spectroscopy with a unified ... More
Totally symmetric dessins with nilpotent automorphism groups of class threeNov 21 2015A dessin is a 2-cell embedding of a connected bipartite graph into an orientable closed surface. An automorphism of a dessin is a permutation of the edges of the underlying graph which preserves the colouring of the vertices and extends to an orientation-preserving ... More
Radio Quiet AGNs as Possible Sources of Ultra-high Energy Cosmic RaysNov 09 2009Dec 17 2009Active galactic nuclei (AGNs) have been one of the most widely discussed sources of ultrahigh-energy cosmic rays (UHECRs). The recent results of Pierre Auger observatory (PAO) have indicated a possible composition change of UHECRs above ~10^{18.5} eV ... More
A two-component jet model for the tidal disruption event Swift J164449.3+573451Nov 21 2012Oct 20 2014We analyze both the early and late time radio and X-ray data of the tidal disruption event Swift J1644+57. The data at early times ($\lesssim 5$ days) necessitates separation of the radio and X-ray emission regions, either spatially or in velocity space. ... More
Scattering of electromagnetic waves from a cone with conformal mapping: application to scanning near-field optical microscopeJan 25 2018We study the response of a conical metallic surface to an external electromagnetic (EM) field by representing the fields in basis functions containing integrable singularities at the tip of the cone. A fast analytical solution is obtained by the conformal ... More
More about the $B$ and $D$ mesons in nuclear matterMay 13 2014Aug 05 2014We calculate the shifts in decay constants of the pseudoscalar $B$ and $D$ mesons in nuclear medium in the frame work of QCD sum rules. We write those shifts in terms of the $B-N$ and $D-N$ scattering lengths and an extra phenomenological parameter entered ... More
Semileptonic $B \rightarrow \bar{D} $ transition in nuclear mediumOct 20 2014Feb 03 2015We study the semileptonic tree-level $B \rightarrow \bar{D}$ transition in the framework of QCD sum rules in nuclear medium. In particular, we calculate the in-medium form factors entering the transition matrix elements defining this decay channel. It ... More
A theory of photospheric emission from relativistic, collimated outflowsAug 14 2012Nov 29 2012Relativistic outflows in the form of jets are common in many astrophysical objects. By their very nature, jets have angle dependent velocity profiles, Gamma = Gamma(r, theta, phi), where Gamma is the outflow Lorentz factor. In this work we consider photospheric ... More
On the mass correction of heavy meson effective theoryOct 06 1995We derive the mass correction lagrangian of the heavy meson effective theory by using the projection operator method. The next leading order of the mass correction and the first order of the chiral expansion are given explicitely.We also consider the ... More
An Online Universal Classifier for Binary, Multi-class and Multi-label ClassificationSep 03 2016Classification involves the learning of the mapping function that associates input samples to corresponding target label. There are two major categories of classification problems: Single-label classification and Multi-label classification. Traditional ... More
Nilpotent dessins: Decomposition theorem and classification of the abelian dessinsAug 19 2015A map is a 2-cell decomposition of an orientable closed surface. A dessin is a bipartite map with a fixed colouring of vertices. A dessin is regular if its group of colour- and orientation-preserving automorphisms acts transitively on the edges, and a ... More
Learning Bayesian Network Structure from Massive Datasets: The "Sparse Candidate" AlgorithmJan 23 2013Learning Bayesian networks is often cast as an optimization problem, where the computational task is to find a structure that maximizes a statistically motivated score. By and large, existing learning tools address this optimization problem using standard ... More
Impact of finite density on spectroscopic parameters of decuplet baryonsOct 30 2016Nov 17 2016The decuplet baryons, $\Delta$, $\Sigma^{*}$, $\Xi^{*}$ and $\Omega^{-}$, are studied in nuclear matter by using the in-medium QCD sum rules. By fixing the three momentum of the particles under consideration at the rest frame of the medium, the negative ... More
Two-Photon Correlation of Spontaneously Generated Broadband Four-Waves MixingDec 05 2011Oct 06 2012We measure the time-energy correlation of broadband, spontaneously generated four wave mixing (FWM), and demonstrate novel time-frequency coupling effects; specifically, we observe a power-dependent splitting of the correlation in both energy and time. ... More
A Web Aggregation Approach for Distributed Randomized PageRank AlgorithmsMar 29 2012The PageRank algorithm employed at Google assigns a measure of importance to each web page for rankings in search results. In our recent papers, we have proposed a distributed randomized approach for this algorithm, where web pages are treated as agents ... More
Colonization of a territory by a stochastic population under a strong Allee effect and a low immigration pressureMar 01 2015Sep 29 2016We study the dynamics of colonization of a territory by a stochastic population at low immigration pressure. We assume a sufficiently strong Allee effect that introduces, in deterministic theory, a large critical population size for colonization. At low ... More
Kerr-lens Mode Locking Without Nonlinear AstigmatismJan 02 2013We demonstrate a Kerr-lens mode locked folded cavity using a planar (non-Brewster) Ti:sapphire crystal as a gain and Kerr medium, thus cancelling the nonlinear astigmatism caused by a Brewster cut Kerr medium. Our method uses a novel cavity folding in ... More
Reconstruction of the environmental correlation function from single emitter photon statistics: a non-Markovian approachDec 03 2012We consider the two-level system approximation of a single emitter driven by a continuous laser pump and simultaneously coupled to the electromagnetic vacuum and to a thermal reservoir beyond the Markovian approximation. We discuss the connection between ... More
Emergence of the Macroscopic Fourier Law from the Microscopic Wave Equation of Diffusive MediumDec 30 2008The Fourier law and the diffusion equation are derived from the Schrodinger equation of a diffusive medium (consisting of a random potential). The theoretical model is backed by numerical simulation. This derivation can easily be generalized to demonstrate ... More
A High Speed Multi-label Classifier based on Extreme Learning MachinesAug 31 2016In this paper a high speed neural network classifier based on extreme learning machines for multi-label classification problem is proposed and dis-cussed. Multi-label classification is a superset of traditional binary and multi-class classification problems. ... More
Mass Segregation of Embedded Clusters in the Milky WayOct 22 2012Embedded clusters are ideal laboratories to understand the early phase of the dynamical evolution of clusters as well as the massive star formation. An interesting observational phenomenon is that some of the embedded clusters show mass segregation, i.e., ... More
Scalar and vector self-energies of heavy baryons in nuclear mediumMay 18 2016Nov 08 2016The in-medium sum rules are employed to calculate the shifts in the mass and residue as well as the scalar and vector self-energies of the heavy $\Lambda_Q, \Sigma_Q$ and $\Xi_Q$ baryons, with Q being $b$ or $c$ quark. The maximum shift in mass due to ... More
Positive and negative parity hyperons in nuclear mediumJun 06 2015Sep 28 2015The effects of nuclear medium on the residue, mass and self energy of the positive and negative parity $\Sigma$, $\Lambda$ and $\Xi$ hyperons are investigated using the QCD sum rule method. In the calculations, the general interpolating currents of hyperons ... More
Impact of finite density on spectroscopic parameters of decuplet baryonsOct 30 2016The decuplet baryons, $\Delta$, $\Sigma^{*}$, $\Xi^{*}$ and $\Omega^{-}$, are studied in nuclear matter by using the in-medium QCD sum rules. By fixing the three momentum of the particles under consideration at the rest frame of the medium, the negative ... More
Dynamical Properties of Internal Shocks RevisitedOct 27 2016Internal shocks between propagating plasma shells, originally ejected at different times with different velocities are believed to play a major role in dissipating the kinetic energy, thereby explaining the observed lightcurve and spectra in a large range ... More
On the spatial coordinate measurement of two identical particlesMar 14 2016Theoretically, the coordinate measurement of two identical particles at a point by two narrowly separated narrow detectors, is interpreted in the limit of shrinking width and separation, as the detection of two particles by a single narrow detector. { ... More
Radiative striped wind model for gamma-ray burstsOct 12 2016In this paper we revisit the striped wind model in which the wind is accelerated by magnetic reconnection. In our treatment, radiation is included as an independent component, and two scenarios are considered. In the first one, radiation cannot stream ... More
Doping effects on the magnetic frustration in the honeycomb iridatesJun 27 2015We investigate the doping effects of magnetic and nonmagnetic impurities injected to the honeycomb iridate sample of Na2IrO3 . Both the doping result in changing the ordering temperature as well as the Curie-Weiss temperature of the parent sample as a ... More
Polarization properties of photospheric emission from relativistic, collimated outflowsSep 29 2013We consider the polarization properties of photospheric emission originating in jets consisting of a highly relativistic core of opening angle theta_j and Lorentz factor Gamma_0, and a surrounding shear layer where the Lorentz factor is decreasing as ... More
Slow entropy for noncompact sets and variational principleNov 24 2011This paper defines and discusses the dimension notion of topological slow entropy of any subset for Z^d actions. Also, the notion of measure-theoretic slow entropy for Z^d actions is presented, which is modified from Brin and Katok [2]. Relations between ... More
Toeplitz Matrix Based Sparse Error Correction in System Identification: Outliers and Random NoisesDec 04 2012In this paper, we consider robust system identification under sparse outliers and random noises. In our problem, system parameters are observed through a Toeplitz matrix. All observations are subject to random noises and a few are corrupted with outliers. ... More
A note on the distribution of admixture segment lengths and ancestry proportions under pulse and two-wave admixture modelsSep 19 2015Admixed populations are formed by the merging of two or more ancestral populations, and the ancestry of each locus in an admixed genome derives from either source. Consider a simple "pulse" admixture model, where populations A and B merged t generations ... More
Rings and modules which are stable under automorphisms of their injective hullsJan 24 2013It is proved, among other results, that a prime right nonsingular ring (in particular, a simple ring) $R$ is right self-injective if $R_R$ is invariant under automorphisms of its injective hull. This answers two questions raised by Singh and Srivastava, ... More
Effects of Spin on High-Energy Radiation from Accreting Black HolesJul 04 2016Aug 17 2016Observations of jets in X-ray binaries show a correlation between radio power and black hole spin. This correlation, if confirmed, points towards the idea that relativistic jets may be powered by the rotational energy of black holes. In order to examine ... More
A Novel Online Real-time Classifier for Multi-label Data StreamsAug 31 2016In this paper, a novel extreme learning machine based online multi-label classifier for real-time data streams is proposed. Multi-label classification is one of the actively researched machine learning paradigm that has gained much attention in the recent ... More
Intra-cavity gain shaping of mode-locked Ti:Sapphire laser oscillationsJan 01 2015The gain properties of an oscillator strongly affect its behavior. When the gain is homogeneous, different modes compete for gain resources in a `winner takes all' manner, whereas with inhomogeneous gain, modes can coexist if they utilize different gain ... More
Octave-Spanning Phase Control for Single-Cycle Bi-PhotonsMar 10 2014Sep 13 2015The quantum correlation of octave-spanning time-energy entangled bi-photons can be as short as a single optical cycle. Many experiments designed to explore and exploit this correlation require a uniform spectral phase (transform-limited) with very low ... More
A renewal theory approach to IBD sharingMar 06 2014Sep 12 2014A long genomic segment inherited by a pair of individuals from a single, recent common ancestor is said to be identical-by-descent (IBD). Shared IBD segments have numerous applications in genetics, from demographic inference to phasing, imputation, pedigree ... More
Two photon absorption and coherent control with broadband down-converted lightJan 15 2004We experimentally demonstrate two-photon absorption (TPA) with broadband down-converted light (squeezed vacuum). Although incoherent and exhibiting the statistics of a thermal noise, broadband down-converted light can induce TPA with the same sharp temporal ... More
Coherent control with broadband squeezed vacuumFeb 05 2003We report the experimental demonstration of coherent control with high power, broadband squeezed vacuum. Although incoherent and exhibiting the statistics of a thermal noise, broadband squeezed vacuum is shown to induce certain two-photon interactions ... More
Will Zigzag Graphene Nanoribbon Turn to Half Metal under Electric Field?Aug 09 2007At B3LYP level of theory, we predict that the half-metallicity in zigzag edge graphene nanoribbon (ZGNR) can be realized when an external electric field is applied across the ribbon. The critical electric field to induce the half-metallicity decreases ... More
Tunable Hydrogen Storage in Magnesium - Transition Metal CompoundsOct 13 2008Magnesium dihydride ($\mgh$) stores 7.7 weight % hydrogen, but it suffers from a high thermodynamic stability and slow (de)hydrogenation kinetics. Alloying Mg with lightweight transition metals (TM = Sc, Ti, V, Cr) aims at improving the thermodynamic ... More
Peak energy clustering and efficiency in compact objectsApr 15 2005Sep 12 2005We study the properties of plasmas containing a low energy thermal photon component at comoving temperature \theta \equiv kT'/m_e c^2 \sim 10^{-5} - 10^{-2} interacting with an energetic electron component, characteristic of, e.g., the dissipation phase ... More
The signature of a wind reverse shock in Gamma-ray bursts afterglowsNov 16 2005Explosions of massive stars are believed to be the source of a significant fraction of gamma-ray bursts (GRBs). If this is indeed the case, then the explosion blast wave propagates into a complex density structure, composed of a stellar wind bounded by ... More
Half-metallic ferromagnetism in transition-metal doped germanium nitride: A first-principles studyMar 31 2010Apr 01 2010The electronic and magnetic properties of transition-metal doped $\beta$-Ge3N4 have been studied using first-principles calculations. The results show that the substitutional transition-metal impurities tend to cluster. The V and Cr doped Ge3N4 compounds ... More