Results for "Ziyu Chen"

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Series-Expansion Thermal Tensor Network Approach for Quantum Lattice ModelsSep 05 2016Mar 26 2017In this work we propose a series-expansion thermal tensor network (SETTN) approach for efficient simulations of quantum lattice models. This continuous-time SETTN method is based on the numerically exact Taylor series expansion of equilibrium density ... More
AsymDPOP: Complete Inference for Asymmetric Distributed Constraint Optimization ProblemsMay 28 2019Jun 04 2019Asymmetric distributed constraint optimization problems (ADCOPs) are an emerging model for coordinating agents with personal preferences. However, the existing inference-based complete algorithms which use local eliminations cannot be applied to ADCOPs, ... More
Significance of self magnetic field in long-distance collimation of laser-generated electron beamsOct 09 2014Long-distance collimation of fast electron beams generated by laser-metallic-wire targets has been observed in recent experiments, while the mechanism behind this phenomenon remains unclear. In this work, we investigate in detail the laser-wire interaction ... More
Thermal Tensor Renormalization Group Simulations of Square-Lattice Quantum Spin ModelsApr 12 2019In this work, we benchmark the well-controlled and numerically accurate exponential thermal tensor renormalization group (XTRG) in the simulation of interacting spin models in two dimensions. Finite temperature introduces a thermal correlation length, ... More
Convolutional Sequence to Sequence Non-intrusive Load MonitoringJun 06 2018A convolutional sequence to sequence non-intrusive load monitoring model is proposed in this paper. Gated linear unit convolutional layers are used to extract information from the sequences of aggregate electricity consumption. Residual blocks are also ... More
Liquid crystal self-assembly of upconversion nanorods enriched by depletion forces for mesostructured material preparationDec 28 2017Monodisperse rod-like colloidal particles are known for spontaneously forming both nematic and smectic liquid crystal phases, but their self-assembly was typically exploited from the fundamental soft condensed matter physics perspective. Here we demonstrate ... More
L-equivalence for degree five elliptic curves, elliptic fibrations and K3 surfacesJul 02 2019We construct nontrivial L-equivalence between curves of genus one and degree five, and between elliptic surfaces of multisection index five. These results give the first examples of L-equivalence for curves (necessarily over non-algebraically closed fields) ... More
Formality conjecture for K3 surfacesMar 11 2018Feb 26 2019We give a proof of the formality conjecture of Kaledin and Lehn: on a complex projective K3 surface, the DG algebra RHom(F,F) is formal for any sheaf F polystable with respect to an ample line bundle. Our main tool is the uniqueness of DG enhancement ... More
The Trajectory of Voice Onset Time with Vocal AgingOct 15 2018Vocal aging, a universal process of human aging, can largely affect one's language use, possibly including some subtle acoustic features of one's utterances like Voice Onset Time. To figure out the time effects, Queen Elizabeth's Christmas speeches are ... More
Topology-driven phase transitions in the classical monomer-dimer-loop modelApr 07 2015Apr 08 2015In this work, we investigate the classical loop models doped with monomers and dimers on a square lattice, whose partition function can be expressed as a tensor network (TN). In the thermodynamic limit, we use the boundary matrix product state technique ... More
Kosterlitz-Thouless transitions and phase diagrams of the interacting monomer-dimer model on a checkerboard latticeApr 07 2015Using the tensor network approach, we investigate the monomer-dimer models on a checkerboard lattice, in which there are interactions (with strength $\nu$) between the parallel dimers on half of the plaquettes. For the fully packed interacting dimer model, ... More
Optimal Paths in Large Deviations of Symmetric Reflected Brownian Motion in the OctantAug 09 2012Jan 31 2013We study the variational problem that arises from consideration of large deviations for semimartingale reflected Brownian motion (SRBM) in the positive octant. Due to the difficulty of the general problem, we consider the case in which the SRBM has rotationally ... More
A Generic Approach for Accelerating Belief Propagation based DCOP Algorithms via A Branch-and-Bound TechniqueJun 17 2019Belief propagation approaches, such as Max-Sum and its variants, are a kind of important methods to solve large-scale Distributed Constraint Optimization Problems (DCOPs). However, for problems with n-ary constraints, these algorithms face a huge challenge ... More
Continuous-Time Thermal Tensor Network Approach for Quantum Lattice ModelsSep 05 2016In this Letter we propose a continuous-time thermal tensor network (TTN) approach for efficient simulations of quantum lattice models. The continuous-time TTN method is based on numerically exact Taylor series expansions of equilibrium density operators ... More
AsymDPOP: Complete Inference for Asymmetric Distributed Constraint Optimization ProblemsMay 28 2019Asymmetric distributed constraint optimization problems (ADCOPs) are an emerging model for coordinating agents with personal preferences. However, the existing inference-based complete algorithms which use local eliminations cannot be applied to ADCOPs, ... More
PT-ISABB: A Hybrid Tree-based Complete Algorithm to Solve Asymmetric Distributed Constraint Optimization ProblemsFeb 16 2019Mar 04 2019Asymmetric Distributed Constraint Optimization Problems (ADCOPs) have emerged as an important formalism in multi-agent community due to their ability to capture personal preferences. However, the existing search-based complete algorithms for ADCOPs can ... More
PT-ISABB: A Hybrid Tree-based Complete Algorithm to Solve Asymmetric Distributed Constraint Optimization ProblemsFeb 16 2019Asymmetric Distributed Constraint Optimization Problems (ADCOPs) have emerged as an important formalism in multi-agent community due to their ability to capture personal preferences. However, the existing search-based complete algorithms for ADCOPs can ... More
A Generic Approach for Accelerating Belief Propagation based DCOP Algorithms via A Branch-and-Bound TechniqueJun 17 2019Jun 18 2019Belief propagation approaches, such as Max-Sum and its variants, are a kind of important methods to solve large-scale Distributed Constraint Optimization Problems (DCOPs). However, for problems with n-ary constraints, these algorithms face a huge challenge ... More
PT-ISABB: A Hybrid Tree-based Complete Algorithm to Solve Asymmetric Distributed Constraint Optimization ProblemsFeb 16 2019Apr 11 2019Asymmetric Distributed Constraint Optimization Problems (ADCOPs) have emerged as an important formalism in multi-agent community due to their ability to capture personal preferences. However, the existing search-based complete algorithms for ADCOPs can ... More
Magnetic Generation due to Mass Difference between Charge CarriersNov 01 2013The possibility of spontaneous magnetization due to the "asymmetry in mass" of charge carriers in a system is investigated. Analysis shows that when the masses of positive and negative charge carriers are identical, no magnetization is predicted. However, ... More
Towards Building the Semantic Map from a Monocular Camera with a Multi-task NetworkJan 17 2019In many robotic applications, especially for the autonomous driving, understanding the semantic information and the geometric structure of surroundings are both essential. Semantic 3D maps, as a carrier of the environmental knowledge, are then intensively ... More
iCare: A Mobile Health Monitoring System for the ElderlyNov 13 2010This paper describes a mobile health monitoring system called iCare for the elderly. We use wireless body sensors and smart phones to monitor the wellbeing of the elderly. It can offer remote monitoring for the elderly anytime anywhere and provide tailored ... More
Optimal Distributed P2P Streaming under Node Degree BoundsAug 31 2010Jun 19 2012We study the problem of maximizing the broadcast rate in peer-to-peer (P2P) systems under \emph{node degree bounds}, i.e., the number of neighbors a node can simultaneously connect to is upper-bounded. The problem is critical for supporting high-quality ... More
Collaborative Global-Local Networks for Memory-Efficient Segmentation of Ultra-High Resolution ImagesMay 15 2019Segmentation of ultra-high resolution images is increasingly demanded, yet poses significant challenges for algorithm efficiency, in particular considering the (GPU) memory limits. Current approaches either downsample an ultra-high resolution image or ... More
Nearest Prime Simplicial Complex for Object RecognitionJun 06 2011The structure representation of data distribution plays an important role in understanding the underlying mechanism of generating data. In this paper, we propose nearest prime simplicial complex approaches (NSC) by utilizing persistent homology to capture ... More
StaQC: A Systematically Mined Question-Code Dataset from Stack OverflowMar 26 2018Stack Overflow (SO) has been a great source of natural language questions and their code solutions (i.e., question-code pairs), which are critical for many tasks including code retrieval and annotation. In most existing research, question-code pairs were ... More
Planecell: Representing the 3D Space with PlanesMar 30 2017Reconstruction based on the stereo camera has received considerable attention recently, but two particular challenges still remain. The first concerns the need to aggregate similar pixels in an effective approach, and the second is to maintain as much ... More
Nef divisors for moduli spaces of complexes with compact supportFeb 02 2016Oct 28 2016In [BM14b], the first author and Macr\`i constructed a family of nef divisors on any moduli space of Bridgeland-stable objects on a smooth projective variety X. In this article, we extend this construction to the setting of any separated scheme Y of finite ... More
Exponential Thermal Tensor Network Approach for Quantum Lattice ModelsDec 30 2017Oct 05 2018We speed up thermal simulations of quantum many-body systems in both one- (1D) and two-dimensional (2D) models in an exponential way by iteratively projecting the thermal density matrix $\hat\rho=e^{-\beta \hat{H}}$ onto itself. We refer to this scheme ... More
Criticality-Enhanced Magnetocaloric Effect in Quantum Spin Chain Material Copper NitrateJul 14 2016Low-dimensional quantum magnets, due to the existence of abundant exotic quantum phases therein and experimental feasibilities in laboratories, continues intriguing people in condensed matter physics. In this work, a comprehensive study of Cu(NO$_3$)$_2$ ... More
From Multiple Nodal Chain to Dirac/Weyl Semimetal and Topological Insulator in Ternary Hexagonal MaterialsDec 05 2017Dirac semimetal (DSM) hosts four-fold degenerate isolated band-crossing points with linear dispersion, around which the quasiparticles resemble the relativistic Dirac Fermions. It can be described by a 4 * 4 massless Dirac Hamiltonian which can be decomposed ... More
FHEDN: A based on context modeling Feature Hierarchy Encoder-Decoder Network for face detectionDec 11 2017Because of affected by weather conditions, camera pose and range, etc. Objects are usually small, blur, occluded and diverse pose in the images gathered from outdoor surveillance cameras or access control system. It is challenging and important to detect ... More
Weyl-loop half metal in Li$_3$(FeO$_3$)$_2$Nov 13 2018Nodal-line metals and semimetals, as interesting topological states of matter, have been mostly studied in nonmagnetic materials. Here, based on first-principles calculations and symmetry analysis, we predict that fully spin-polarized Weyl loops can be ... More
Short-term Load Forecasting with Deep Residual NetworksMay 30 2018We present in this paper a model for forecasting short-term power loads based on deep residual networks. The proposed model is able to integrate domain knowledge and researchers' understanding of the task by virtue of different neural network building ... More
Interactive Semantic Parsing for If-Then Recipes via Hierarchical Reinforcement LearningAug 21 2018Nov 14 2018Given a text description, most existing semantic parsers synthesize a program in one shot. However, it is quite challenging to produce a correct program solely based on the description, which in reality is often ambiguous or incomplete. In this paper, ... More
Bayesian Optimization in AlphaGoDec 17 2018During the development of AlphaGo, its many hyper-parameters were tuned with Bayesian optimization multiple times. This automatic tuning process resulted in substantial improvements in playing strength. For example, prior to the match with Lee Sedol, ... More
Deep Music Analogy Via Latent Representation DisentanglementJun 09 2019Jun 28 2019Analogy-making is a key method for computer algorithms to generate both natural and creative music pieces. In general, an analogy is made by partially transferring the music abstractions, i.e., high-level representations and their relationships, from ... More
Interaction effect in two-dimensional Dirac fermionsApr 12 2013Jul 23 2013Based on the Dirac equations in the two-dimensional $\pi-$ flux model, we study the interaction effects both in nontrivial gapped and gapless Dirac equations with numerical exact diagonalization method. In the presence of the nearest and next nearest ... More
Deep Music Analogy Via Latent Representation DisentanglementJun 09 2019Jul 08 2019Analogy-making is a key method for computer algorithms to generate both natural and creative music pieces. In general, an analogy is made by partially transferring the music abstractions, i.e., high-level representations and their relationships, from ... More
Transductive Zero-Shot Learning with Visual Structure ConstraintJan 06 2019Zero-shot Learning (ZSL) aims to recognize objects of the unseen classes, whose instances may not have been seen during training. It associates seen and unseen classes with the common semantic space and provides the visual features for each data instance. ... More
Deep Music Analogy Via Latent Representation DisentanglementJun 09 2019Analogy is a key solution to automated music generation, featured by its ability to generate both natural and creative pieces based on only a few examples. In general, an analogy is made by partially transferring the music abstractions, i.e., high-level ... More
Pressure-induced phase transitions of multiferroic BiFeO3Aug 29 2013Pressure-induced phase transitions of multiferroic BiFeO3 have been investigated using synchrotron radiation X-ray diffraction with diamond anvil cell technique at room temperature. Present experimental data clearly show that rhombohedral (R3c) phase ... More
Electronic structure of LaFe1-xCoxAsO from first principle calculationsJul 20 2008Aug 06 2008Based on the first-principles calculations, we have investigated the geometry, binding properties, density of states and band structures of the novel superconductor LaFe1-xCoxAsO and its parent compounds with the ZrCuSiAs structure. We demonstrate that ... More
Hybrid Dirac Semimetal in CaAgBi Materials FamilyJun 13 2017Based on their formation mechanisms, Dirac points in three-dimensional systems can be classified as accidental or essential. The former can be further distinguished into type-I and type-II, depending on whether the Dirac cone spectrum is completely tipped ... More
Two-dimensional second-order topological insulator in graphdiyneApr 22 2019A second-order topological insulator (SOTI) in $d$ spatial dimensions features topologically protected gapless states at its $(d-2)$-dimensional boundary at the intersection of two crystal faces, but is gapped otherwise. As a novel topological state, ... More
Formality conjecture for K3 surfacesMar 11 2018Jul 04 2018We give a proof of the formality conjecture of Kaledin and Lehn: on a complex projective K3 surface, the DG algebra RHom(F,F) is formal for any sheaf F polystable with respect to an ample line bundle. Our main tool is the uniqueness of DG enhancement ... More
Decomposition of noncommutative U(1) gauge potentialDec 02 2007We investigate the decomposition of noncommutative gauge potential $\hat{A_{i}}$, and find it has inner structure, namely, $\hat{A_{i}}$ can be decomposed in two parts $\hat{b_{i}}$ and $\hat{a_{i}}$, here $\hat{b_{i}}$ satisfies gauge transformations ... More
Temperature-dependent bulk viscosity of nitrogen gas determined from spontaneous Rayleigh-Brillouin scatteringMar 23 2013Values for the bulk viscosity of molecular nitrogen gas (N2) were derived from spontaneous Rayleigh-Brillouin (RB) scattering at ultraviolet wavelengths (366.8 nm) and at a 90 degree scattering angle. Analysis of the scattering profiles yield values showing ... More
A systematic study of Rayleigh-Brillouin scattering in air, N2 and O2 gasesSep 10 2014Spontaneous Rayleigh-Brillouin scattering experiments in air, N2 and O2 have been performed for a wide range of temperatures and pressures at a wavelength of 403 nm and at a 90 degrees scattering angle. Measurements of the Rayleigh-Brillouin spectral ... More
A Top-down Model for Cash CLOApr 16 2010We propose a top-down model for cash CLO. This model can consistently price cash CLO tranches both within the same deal and across different deals. Meaningful risk measures for cash CLO tranches can also be defined and computed. This method is self-consistent, ... More
Strong Cosmic Censorship in higher-dimensional Reissner-Nordström-de Sitter spacetimeFeb 05 2019Apr 01 2019It was recently shown that Strong Cosmic Censorship might be violated for near-extremally-charged black holes in 4-dimensional de Sitter space under scalar perturbations. Here, we extend the study of neutral massless scalar perturbations in higher dimensions ... More
Duality Spectral Sequences for Weierstrass Fibrations and ApplicationsJun 06 2017We study duality spectral sequences for Weierstrass fibrations. Using these spectral sequences, we show that on a K-trivial Weierstrass threefold over a K-numerically trivial surface, any line bundle of nonzero fiber degree is taken by a Fourier-Mukai ... More
Birational Geometry of Singular Moduli Spaces of O'Grady TypeApr 27 2014Nov 19 2016Following Bayer and Macr\`{i}, we study the birational geometry of singular moduli spaces $M$ of sheaves on a K3 surface $X$ which admit symplectic resolutions. More precisely, we use the Bayer-Macr\`{i} map from the space of Bridgeland stability conditions ... More
A Framework for Automated Pop-song Melody Generation with Piano Accompaniment ArrangementDec 28 2018We contribute a pop-song automation framework for lead melody generation and accompaniment arrangement. The framework reflects the major procedures of human music composition, generating both lead melody and piano accompaniment by a unified strategy. ... More
Birational Geometry of Singular Moduli Spaces of O'Grady TypeApr 27 2014Jun 16 2014Following Bayer and Macr\`{i}, we study the birational geometry of singular moduli spaces $M$ of sheaves on a K3 surface $X$ which admit symplectic resolutions. More precisely, we use the Bayer-Macr\`{i} map from the space of Bridgeland stability conditions ... More
Preservation of semistability under Fourier-Mukai transformsOct 01 2015For a trivial elliptic fibration $X=C \times S$ with $C$ an elliptic curve and $S$ a projective K3 surface of Picard rank $1$, we study how various notions of stability behave under the Fourier-Mukai autoequivalence $\Phi$ on $D^b(X)$, where $\Phi$ is ... More
Representing stable complexes on projective spacesFeb 22 2012Jan 17 2014We give an explicit proof of a Bogomolov-type inequality for $c_3$ of reflexive sheaves on $\mathbb{P}^3$. Then, using resolutions of rank-two reflexive sheaves on $\mathbb{P}^3$, we prove that some strata of the moduli of rank-two complexes that are ... More
Efficient Destination Prediction Based on Route Choices with Transition Matrix OptimizationNov 08 2017Jul 10 2018Destination prediction is an essential task in a variety of mobile applications. In this paper, we optimize the matrix operation and adapt a semi-lazy framework to improve the prediction accuracy and efficiency of a state-of-the-art approach. To this ... More
Thermocapillary-driven fluid flow within microchannelsFeb 01 2018Surface tension gradients induce Marangoni flow, which may be exploited for fluid transport. At the micrometer scale, these surface-driven flows can be more significant than those driven by pressure. By introducing fluid-fluid interfaces on the walls ... More
Giant Magnetic Quantum Oscillations and Chiral Anomaly in the Thermal Conductivity of a Weyl SemimetalJan 25 2018Giant quantum oscillations of magneto-thermal conductivity amounting to two orders of magnitude of the estimation based on the Wiedemann-Franz law have been observed in the prototypical Weyl semimetal TaAs. The characteristic oscillation frequency ($F$ ... More
Theoretical Analysis of Bayesian Optimisation with Unknown Gaussian Process Hyper-ParametersJun 30 2014Bayesian optimisation has gained great popularity as a tool for optimising the parameters of machine learning algorithms and models. Somewhat ironically, setting up the hyper-parameters of Bayesian optimisation methods is notoriously hard. While reasonable ... More
Nef divisors for moduli spaces of complexes with compact supportFeb 02 2016In [BM14b], the first author and Macr\`i constructed a family of nef divisors on any moduli space of Bridgeland-stable objects on a smooth projective variety X. In this article, we extend this construction to the setting of any separated scheme Y of finite ... More
Measuring Two-Event Structural Correlations on GraphsAug 01 2012Real-life graphs usually have various kinds of events happening on them, e.g., product purchases in online social networks and intrusion alerts in computer networks. The occurrences of events on the same graph could be correlated, exhibiting either attraction ... More
Weak solutions for forward--backward SDEs--a martingale problem approachJan 19 2009In this paper, we propose a new notion of Forward--Backward Martingale Problem (FBMP), and study its relationship with the weak solution to the forward--backward stochastic differential equations (FBSDEs). The FBMP extends the idea of the well-known (forward) ... More
Giant magnetic quantum oscillations in the thermal conductivity of TaAs: Indications of chiral zero soundJan 25 2018Jun 02 2019Charge transport of topological semimetals has been in the focus of intensive investigations because of their non-trivial band topology. Heat transport of these materials, on the other hand, is largely unexplored and remains elusive. Here we report on ... More
Error Analysis for the Particle Filter: Methods and Theoretical SupportMar 26 2019The particle filter is a popular Bayesian filtering algorithm for use in cases where the state-space model is nonlinear and/or the random terms (initial state or noises) are non-Gaussian distributed. We study the behavior of the error in the particle ... More
Generative Modeling using the Sliced Wasserstein DistanceMar 29 2018Generative Adversarial Nets (GANs) are very successful at modeling distributions from given samples, even in the high-dimensional case. However, their formulation is also known to be hard to optimize and often not stable. While this is particularly true ... More
Self-Avoiding Random Dynamics on Integer Complex SystemsNov 23 2011Nov 25 2011This paper introduces a new specialized algorithm for equilibrium Monte Carlo sampling of binary-valued systems, which allows for large moves in the state space. This is achieved by constructing self-avoiding walks (SAWs) in the state space. As a consequence, ... More
CoaCor: Code Annotation for Code Retrieval with Reinforcement LearningMar 13 2019To accelerate software development, much research has been performed to help people understand and reuse the huge amount of available code resources. Two important tasks have been widely studied: code retrieval, which aims to retrieve code snippets relevant ... More
Sequential Joint Spectrum Sensing and Channel Estimation for Dynamic Spectrum AccessJan 22 2014Dynamic spectrum access under channel uncertainties is considered. With the goal of maximizing the secondary user (SU) throughput subject to constraints on the primary user (PU) outage probability we formulate a joint problem of spectrum sensing and channel ... More
Instance-Level Segmentation for Autonomous Driving with Deep Densely Connected MRFsDec 21 2015Apr 27 2016Our aim is to provide a pixel-wise instance-level labeling of a monocular image in the context of autonomous driving. We build on recent work [Zhang et al., ICCV15] that trained a convolutional neural net to predict instance labeling in local image patches, ... More
Adaptive Hamiltonian and Riemann Manifold Monte Carlo SamplersFeb 25 2013In this paper we address the widely-experienced difficulty in tuning Hamiltonian-based Monte Carlo samplers. We develop an algorithm that allows for the adaptation of Hamiltonian and Riemann manifold Hamiltonian Monte Carlo samplers using Bayesian optimization ... More
Bayesian Optimisation for Machine TranslationDec 22 2014This paper presents novel Bayesian optimisation algorithms for minimum error rate training of statistical machine translation systems. We explore two classes of algorithms for efficiently exploring the translation space, with the first based on N-best ... More
Creativity: Generating Diverse Questions using Variational AutoencodersApr 11 2017Generating diverse questions for given images is an important task for computational education, entertainment and AI assistants. Different from many conventional prediction techniques is the need for algorithms to generate a diverse set of plausible questions, ... More
The AC multi-harmonic magnetic susceptibility measurement setup at the LNF-INFNApr 29 2014The AC magnetic susceptibility is a fundamental method in materials science, which allows to probe the dynamic magnetic response of magnetic materials and superconductors. The LAMPS laboratory at the Laboratori Nazionali di Frascati of the INFN hosts ... More
Function Space Particle Optimization for Bayesian Neural NetworksFeb 26 2019While Bayesian neural networks (BNNs) have drawn increasing attention, their posterior inference remains challenging, due to the high-dimensional and over-parameterized nature. To address this issue, several highly flexible and scalable variational inference ... More
Monocular Object Instance Segmentation and Depth Ordering with CNNsMay 12 2015Dec 18 2015In this paper we tackle the problem of instance-level segmentation and depth ordering from a single monocular image. Towards this goal, we take advantage of convolutional neural nets and train them to directly predict instance-level segmentations where ... More
Total transmission and total reflection of acoustic wave by zero index metamaterials loaded with general solid defectsJul 19 2013Aug 19 2013This work investigates acoustic wave transmission property through a zero index metamaterials (ZIM) waveguide embedded with a general solid defect. Total transmission and total reflection can be achieved by adjusting the parameters of the solid defect. ... More
Rayleigh-Brillouin scattering profiles of air at different temperatures and pressuresJul 02 2013Rayleigh Brillouin (RB) scattering profiles for air have been recorded for the temperature range from 255 to 340 K and the pressure range from 640 to 3300 mbar, covering the conditions relevant for the Earth's atmosphere and for planned atmospheric light ... More
Rayleigh-Brillouin scattering of carbon dioxideApr 25 2014The spectral lineshape of spontaneous Rayleigh-Brillouin scattering in CO2 is studied in a range of pressures. The spectrum is influenced by the bulk viscosity, which is a relaxation phenomenon involving the internal degrees of freedom of the molecule. ... More
Dynamic Switch-Controller Association and Control Devolution for SDN SystemsFeb 10 2017Sep 06 2017In software-defined networking (SDN), as data plane scale expands, scalability and reliability of the control plane have become major concerns. To mitigate such concerns, two kinds of solutions have been proposed separately. One is multi- controller architecture, ... More
Bayesian Optimization for Adaptive MCMCOct 29 2011This paper proposes a new randomized strategy for adaptive MCMC using Bayesian optimization. This approach applies to non-differentiable objective functions and trades off exploration and exploitation to reduce the number of potentially costly objective ... More
The geometry of degenerations of Hilbert schemes of pointsFeb 02 2018Feb 16 2018Given a strict simple degeneration $f \colon X\to C$ the first three authors previously constructed a degeneration $I^n_{X/C} \to C$ of the relative degree $n$ Hilbert scheme of $0$-dimensional subschemes. In this paper we investigate the geometry of ... More
Deep Reinforcement Learning for Sponsored Search Real-time BiddingMar 01 2018Bidding optimization is one of the most critical problems in online advertising. Sponsored search (SS) auction, due to the randomness of user query behavior and platform nature, usually adopts keyword-level bidding strategies. In contrast, the display ... More
ArcticNet: A Deep Learning Solution to Classify Arctic WetlandsJun 01 2019Arctic environments are rapidly changing under the warming climate. Of particular interest are wetlands, a type of ecosystem that constitutes the most effective terrestrial long-term carbon store. As permafrost thaws, the carbon that was locked in these ... More
Function Space Particle Optimization for Bayesian Neural NetworksFeb 26 2019May 08 2019While Bayesian neural networks (BNNs) have drawn increasing attention, their posterior inference remains challenging, due to the high-dimensional and over-parameterized nature. To address this issue, several highly flexible and scalable variational inference ... More
Bayesian Multi-Scale Optimistic OptimizationFeb 27 2014Bayesian optimization is a powerful global optimization technique for expensive black-box functions. One of its shortcomings is that it requires auxiliary optimization of an acquisition function at each iteration. This auxiliary optimization can be costly ... More
Estimates of Dirichlet Eigenvalues for a Class of Sub-elliptic OperatorsMay 31 2019Let $\Omega$ be a bounded connected open subset in $\mathbb{R}^n$ with smooth boundary $\partial\Omega$. Suppose that we have a system of real smooth vector fields $X=(X_{1},X_{2},$ $\cdots,X_{m})$ defined on a neighborhood of $\overline{\Omega}$ that ... More
Spin and hyperelliptic structures of log twisted differentialsOct 17 2016Using stable log maps, we introduce log twisted differentials extending the notion of abelian differentials to the Deligne-Mumford boundary of stable curves. The moduli stack of log twisted differentials provides a compactification of the strata of abelian ... More
On the Imbedding Problem for Three-state Time Homogeneous Markov Chains with Coinciding Negative EigenvaluesSep 11 2010For an indecomposable $3\times 3$ stochastic matrix (i.e., 1-step transition probability matrix) with coinciding negative eigenvalues, a new necessary and sufficient condition of the imbedding problem for time homogeneous Markov chains is shown by means ... More
On the anti-canonical geometry of weak $\mathbb{Q}$-Fano threefolds, IIAug 16 2017By a canonical (resp. terminal) weak $\mathbb{Q}$-Fano $3$-fold we mean a normal projective one with at worst canonical (resp. terminal) singularities on which the anti-canonical divisor is $\mathbb{Q}$-Cartier, nef and big. For a canonical weak $\mathbb{Q}$-Fano ... More
On the anti-canonical geometry of $\mathbb{Q}$-Fano 3-foldsAug 27 2014Feb 02 2015For a $\mathbb{Q}$-Fano 3-fold $X$ on which $K_X$ is a canonical divisor, we investigate the geometry induced from the linear system $|-mK_X|$ in this paper and prove that the anti-$m$-canonical map $\varphi_{-m}$ is birational onto its image for all ... More
Delay-Optimal Buffer-Aware Probabilistic Scheduling with Adaptive TransmissionSep 09 2015Cross-layer scheduling is a promising way to improve Quality of Service (QoS) given a power constraint. In this paper, we investigate the system with random data arrival and adaptive transmission. Probabilistic scheduling strategies aware of the buffer ... More
Orthogonal Quantum Group Invariants of LinksJul 09 2010We study the Chern-Simons partition function of orthogonal quantum group invariants, and propose a new orthogonal Labastida-Mari\~{n}o-Ooguri-Vafa conjecture as well as degree conjecture for free energy associated to the orthogonal Chern-Simons partition ... More
Gravitational instantons with faster than quadratic curvature decay (I)May 07 2015In this paper, we study gravitational instantons (i.e., complete hyperk\"aler 4-manifolds with faster than quadratic curvature decay). We prove three main theorems: 1.Any gravitational instanton must have known end----ALE, ALF, ALG or ALH. 2.In ALG and ... More
Exact Methods for Multistage Estimation of a Binomial ProportionFeb 13 2013We first review existing sequential methods for estimating a binomial proportion. Afterward, we propose a new family of group sequential sampling schemes for estimating a binomial proportion with prescribed margin of error and confidence level. In particular, ... More
Embedding of tenable and balanced urn scheme into continuous-time Pólya processNov 29 2016We study poissonized tenable and balanced urns on two colors, say white and blue. In particular, we look at the process obtained by embedding a generalized P\'{o}lya-Eggenberger urn into continuous time. We analyze the number of white and blue balls after ... More
HSEARCH: fast and accurate protein sequence motif search and clusteringJan 02 2017Protein motifs are conserved fragments occurred frequently in protein sequences. They have significant functions, such as active site of an enzyme. Search and clustering protein sequence motifs are computational intensive. Most existing methods are not ... More
Mathematical foundation of nonequilibrium fluctuation-dissipation theorems for inhomogeneous diffusion processes with unbounded coefficientsAug 30 2017Sep 24 2017Nonequilibrium fluctuation-dissipation theorems (FDTs) are one of the most important advances in stochastic thermodynamics over the past two decades. Here we provide a rigourous mathematical theory of two types of nonequilibrium FDTs for inhomogeneous ... More
Faster Deterministic Algorithms for Packing, Matching and $t$-Dominating Set ProblemsJun 15 2013In this paper, we devise three deterministic algorithms for solving the $m$-set $k$-packing, $m$-dimensional $k$-matching, and $t$-dominating set problems in time $O^*(5.44^{mk})$, $O^*(5.44^{(m-1)k})$ and $O^*(5.44^{t})$, respectively. Although recently ... More