Results for "Yee Hui Lee"

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Systematic study of color spaces and components for the segmentation of sky/cloud imagesJan 17 2017Sky/cloud imaging using ground-based Whole Sky Imagers (WSI) is a cost-effective means to understanding cloud cover and weather patterns. The accurate segmentation of clouds in these images is a challenging task, as clouds do not possess any clear structure. ... More
Color-based Segmentation of Sky/Cloud Images From Ground-based CamerasJun 12 2016Sky/cloud images captured by ground-based cameras (a.k.a. whole sky imagers) are increasingly used nowadays because of their applications in a number of fields, including climate modeling, weather prediction, renewable energy generation, and satellite ... More
High-Dynamic-Range Imaging for Cloud SegmentationMar 02 2018Sky/cloud images obtained from ground-based sky-cameras are usually captured using a fish-eye lens with a wide field of view. However, the sky exhibits a large dynamic range in terms of luminance, more than a conventional camera can capture. It is thus ... More
Predicting GPS-based PWV Measurements Using Exponential SmoothingMar 15 2019Global Positioning System (GPS) derived precipitable water vapor (PWV) is extensively being used in atmospheric remote sensing for applications like rainfall prediction. Many applications require PWV values with good resolution and without any missing ... More
On the Importance of PWV in Detecting PrecipitationApr 19 2018With a rapid increase in the number of geostationary satellites around the earth's orbit, there has been a renewed interest in using Global Positioning System (GPS) to understand several phenomenon in earth's atmosphere. Such study using GPS devices are ... More
Design of low-cost, compact and weather-proof whole sky imagers for high-dynamic-range capturesApr 19 2017Ground-based whole sky imagers are popular for monitoring cloud formations, which is necessary for various applications. We present two new Wide Angle High-Resolution Sky Imaging System (WAHRSIS) models, which were designed especially to withstand the ... More
Analyzing Cloud Optical Properties Using Sky CamerasAug 24 2017Clouds play a significant role in the fluctuation of solar radiation received by the earth's surface. It is important to study the various cloud properties, as it impacts the total solar irradiance falling on the earth's surface. One of such important ... More
Detecting Rainfall Onset Using Sky ImagesOct 21 2016Ground-based sky cameras (popularly known as Whole Sky Imagers) are increasingly used now-a-days for continuous monitoring of the atmosphere. These imagers have higher temporal and spatial resolutions compared to conventional satellite images. In this ... More
Machine Learning Techniques and Applications For Ground-based Image AnalysisJun 09 2016Ground-based whole sky cameras have opened up new opportunities for monitoring the earth's atmosphere. These cameras are an important complement to satellite images by providing geoscientists with cheaper, faster, and more localized data. The images captured ... More
Estimation of solar irradiance using ground-based whole sky imagersJun 08 2016Apr 06 2017Ground-based whole sky imagers (WSIs) can provide localized images of the sky of high temporal and spatial resolution, which permits fine-grained cloud observation. In this paper, we show how images taken by WSIs can be used to estimate solar radiation. ... More
Study of Clear Sky Models for SingaporeAug 24 2017The estimation of total solar irradiance falling on the earth's surface is important in the field of solar energy generation and forecasting. Several clear-sky solar radiation models have been developed over the last few decades. Most of these models ... More
Multi-label Cloud Segmentation Using a Deep NetworkMar 15 2019Different empirical models have been developed for cloud detection. There is a growing interest in using the ground-based sky/cloud images for this purpose. Several methods exist that perform binary segmentation of clouds. In this paper, we propose to ... More
Short-term prediction of localized cloud motion using ground-based sky imagersOct 21 2016Fine-scale short-term cloud motion prediction is needed for several applications, including solar energy generation and satellite communications. In tropical regions such as Singapore, clouds are mostly formed by convection; they are very localized, and ... More
Nighttime sky/cloud image segmentationMay 30 2017Imaging the atmosphere using ground-based sky cameras is a popular approach to study various atmospheric phenomena. However, it usually focuses on the daytime. Nighttime sky/cloud images are darker and noisier, and thus harder to analyze. An accurate ... More
Rough Set Based Color Channel SelectionNov 03 2016Color channel selection is essential for accurate segmentation of sky and clouds in images obtained from ground-based sky cameras. Most prior works in cloud segmentation use threshold based methods on color channels selected in an ad-hoc manner. In this ... More
Analyzing Solar Irradiance Variation From GPS and CamerasApr 19 2018The total amount of solar irradiance falling on the earth's surface is an important area of study amongst the photo-voltaic (PV) engineers and remote sensing analysts. The received solar irradiance impacts the total amount of generated solar energy. However, ... More
Correlating Satellite Cloud Cover with Sky CamerasAug 24 2017The role of clouds is manifold in understanding the various events in the atmosphere, and also in studying the radiative balance of the earth. The conventional manner of such cloud analysis is performed mainly via satellite images. However, because of ... More
CloudSegNet: A Deep Network for Nychthemeron Cloud Image SegmentationApr 16 2019We analyze clouds in the earth's atmosphere using ground-based sky cameras. An accurate segmentation of clouds in the captured sky/cloud image is difficult, owing to the fuzzy boundaries of clouds. Several techniques have been proposed that use color ... More
WAHRSIS: A Low-cost, High-resolution Whole Sky Imager With Near-Infrared CapabilitiesMay 21 2016Apr 19 2017Cloud imaging using ground-based whole sky imagers is essential for a fine-grained understanding of the effects of cloud formations, which can be useful in many applications. Some such imagers are available commercially, but their cost is relatively high, ... More
A Data-driven Approach to Detecting Precipitation from Meteorological Sensor DataMay 04 2018Precipitation is dependent on a myriad of atmospheric conditions. In this paper, we study how certain atmospheric parameters impact the occurrence of rainfall. We propose a data-driven, machine-learning based methodology to detect precipitation using ... More
Systematic Study of Weather Variables for Rainfall DetectionMay 04 2018Numerous weather parameters affect the occurrence and amount of rainfall. Therefore, it is important to study these parameters and their interdependency. In this paper, different weather and time-related variables -- relative humidity, solar radiation, ... More
A Data-Driven Approach for Accurate Rainfall PredictionJul 10 2019In recent years, there has been growing interest in using Precipitable Water Vapor (PWV) derived from Global Positioning System (GPS) signal delays to predict rainfall. However, the occurrence of rainfall is dependent on a myriad of atmospheric parameters. ... More
Cloud Radiative Effect Study Using Sky CameraMar 15 2017The analysis of clouds in the earth's atmosphere is important for a variety of applications, viz. weather reporting, climate forecasting, and solar energy generation. In this paper, we focus our attention on the impact of cloud on the total solar irradiance ... More
A Potential Low Cost Remote Sensing Using GPS Derived PWVMay 04 2018In this paper, the Precipitable Water Vapor (PWV) content of the atmosphere is derived using the Global Positioning System (GPS) signal delays. The PWV values from GPS are calculated at different elevation cut-off angles. It was found that the significant ... More
Face changing companion of the redback millisecond pulsar PSR J1048+2339Jan 07 2019We present optical observations of the redback millisecond pulsar PSR J1048+2339, which is a 4.66 ms radio pulsar in a compact binary with an orbital period of six hours. We obtained high-quality light curves of PSR J1048+2339 with the Lulin 1 m Telescope. ... More
Perturbative Expansion around the Gaussian Effective Action: The Background Field MethodJul 02 1997Aug 21 1997We develop a systematic method of the perturbative expansion around the Gaussian effective action based on the background field method. We show, by applying the method to the quantum mechanical anharmonic oscillator problem, that even the first non-trivial ... More
Universal Scaling Laws in Schottky Heterostructures Based on Two-Dimensional MaterialsMar 05 2018Jul 19 2018We identify a new universality in the carrier transport of two-dimensional(2D)-material-based Schottky heterostructures. We show that the reversed saturation current ($\mathcal{J}$) scales universally with temperature ($T$) as $ \log(\mathcal{J}/T^{\beta}) ... More
Vortex Solutions of Four-fermion Theory coupled to a Yang-Mills-Chern-Simons Gauge FieldFeb 10 1998Mar 14 1998We have constructed a four-fermion theory coupled to a Yang-Mills-Chern-Simons gauge field which admits static multi-vortex solutions. This is achieved through the introduction of an anomalous magnetic interation term in addition to the usual minimal ... More
Perturbative Expansion around the Gaussian Effective Potential of the Fermion Field TheoryApr 14 1998Jul 21 1998We have extended the perturbative expansion method around the Gaussian effective action to the fermionic field theory, by taking the 2-dimensional Gross-Neveu model as an example. We have computed both the zero temperature and the finite temperature effective ... More
Interaction Methods for Smart GlassesJul 31 2017Since the launch of Google Glass in 2014, smart glasses have mainly been designed to support micro-interactions. The ultimate goal for them to become an augmented reality interface has not yet been attained due to an encumbrance of controls. Augmented ... More
The N=1* Theories on R^{1+2} X S^1 with Twisted Boundary ConditionsMar 06 2004Sep 06 2004We explore the N=1* theories compactified on a circle with twisted boundary conditions. The gauge algebra of these theories are the so-called twisted affine Lie algebra. We propose the exact superpotentials by guessing the sum of all monopole-instanton ... More
Vortex Solutions of Nonrelativistic Fermion and Scalar Field Theories Coupled to Maxwell-Chern-Simons theoriesMar 16 1999Aug 26 1999We have constructed nonrelativistic fermion and scalar field theories coupled to a Maxwell-Chern-Simons gauge field which admit static multi-vortex solutions. This is achieved by introducing a magnetic coupling term in addition to the usual minimal coupling. ... More
Vortex solutions of a Maxwell-Chern-Simons field coupled to four-fermion theoryFeb 04 1997We find the static vortex solutions of the model of Maxwell-Chern-Simons gauge field coupled to a (2+1)-dimensional four-fermion theory. Especially, we introduce two matter currents coupled to the gauge field minimally: the electromagnetic current and ... More
Differential structure on the $κ$-Minkowski spacetime from twistAug 21 2008Sep 06 2008We study four dimensional $\kappa$-Minkowski spacetime constructed by the twist deformation of $U(igl(4,R))$. We demonstrate that the differential structure of such twist-deformed $\kappa$-Minkowski spacetime is closed in four dimensions contrary to the ... More
Supertubes in Field TheoriesMar 23 2006To a domain wall or string object, Noether charge and topological spatial objects can be attracted, forming a composite BPS (Bogomolny-Prasad-Sommerfield) object. We consider two field theories and derive a new BPS bound on composite linear solitons involving ... More
Holographic Nuclear Matter in AdS/QCDJul 18 2007Jul 26 2007We study the physics with finite nuclear density in the framework of AdS/QCD with holographic baryon field included. Based on a mean field type approach, we introduce the nucleon density as a bi-fermion condensate of the lowest mode of the baryon field ... More
Scalar Field theory in $κ$-Minkowski spacetime from twistDec 31 2008Jan 30 2009Using the twist deformation of $U(igl(4,R))$, the linear part of the diffeomorphism, we define a scalar function and construct a free scalar field theory in four-dimensional $\kappa$-Minkowski spacetime. The action in momentum space turns out to differ ... More
Electromagnetic Nucleon-to-Delta Transition in Holographic QCDApr 23 2009Sep 08 2009We study nucleon-to-delta electromagnetic transition form factors and relations between them within the framework of holographic dual model of QCD proposed by Sakai and Sugimoto. In this setup, baryons appear as topological solitons of the five dimensional ... More
The generation of ground state structures and electronic properties of ternary AlkTilNim clusters (k+l+m=4) from a two-stage DFT global searching approachOct 31 2018Structural and electronic properties of ternary clusters AlkTilNim, where k, l, and m are integers and k + l + m = 4 are investigated. These clusters are generated and studied by performing a two-stage density functional theory (DFT) calculations using ... More
Generation of ground state structures and electronic properties of ternary Al$_x$Ti$_y$Ni$_z$ clusters (x+y+z=6) with a two-stage DFT global search approachApr 04 2019Jul 08 2019The structural and electronic properties of ternary AlxTiyNiz clusters, where x, y, and z are integers and x + y + z = 6 are investigated. Both SVWN and B3LYP exchange-correlation functionals are employed in a two-stage density functional theory (DFT) ... More
A Survey of Automatic Facial Micro-expression Analysis: Databases, Methods and ChallengesJun 15 2018Over the last few years, automatic facial micro-expression analysis has garnered increasing attention from experts across different disciplines because of its potential applications in various fields such as clinical diagnosis, forensic investigation ... More
Human group formation in online guilds and offline gangs driven by common team dynamicDec 12 2008Oct 08 2009Quantifying human group dynamics represents a unique challenge. Unlike animals and other biological systems, humans form groups in both real (offline) and virtual (online) spaces -- from potentially dangerous street gangs populated mostly by disaffected ... More
Comment on `Energy transfer, entanglement and decoherence in a molecular dimer interacting with a phonon bath'Dec 16 2013We show that the influence of the shared phonon bath considered in H. Hossein-Nejad and G. D. Scholes, New J. Phys. 12, 065045 (2010) on the exciton transfer in a two-molecule system can be reproduced by that of an independent bath model.
Quantifiable simulation of quantum computation beyond stochastic ensemble computationApr 26 2016Aug 24 2018In this study, a distinctive feature of quantum computation (QC) is characterized. To this end, a seemingly-powerful classical computing model, called "stochastic ensemble machine (SEnM)," is considered. The SEnM runs with an ensemble consisting of finite ... More
Phonon-induced dynamic resonance energy transferApr 15 2013May 08 2014In a network of interacting quantum systems achieving fast coherent energy transfer is a challenging task. While quantum systems are susceptible to a wide range of environmental factors, in many physical settings their interactions with quantized vibrations, ... More
Set Transformer: A Framework for Attention-based Permutation-Invariant Neural NetworksOct 01 2018May 26 2019Many machine learning tasks such as multiple instance learning, 3D shape recognition, and few-shot image classification are defined on sets of instances. Since solutions to such problems do not depend on the order of elements of the set, models used to ... More
A Probabilistic Framework for Representing Dialog Systems and Entropy-Based Dialog Management through Dynamic Stochastic State EvolutionApr 27 2015In this paper, we present a probabilistic framework for goal-driven spoken dialog systems. A new dynamic stochastic state (DS-state) is then defined to characterize the goal set of a dialog state at different stages of the dialog process. Furthermore, ... More
Tautological systems under the conifold transition on $G(2, 4)$Feb 02 2016Feb 03 2016Via a natural degeneration of Grassmannian manifolds $G(k,n)$ to Gorenstein toric Fano varieties $P(k,n)$ with conifold singularities, we suggest an approach to study the relation between the tautological system on $G(k,n)$ and the extended GKZ system ... More
Acoustics-guided evaluation (AGE): a new measure for estimating performance of speech enhancement algorithms for robust ASRNov 28 2018One challenging problem of robust automatic speech recognition (ASR) is how to measure the goodness of a speech enhancement algorithm (SEA) without calculating the word error rate (WER) due to the high costs of manual transcriptions, language modeling ... More
Radio Cores of Bipolar Nebulae: Search for Collimated WindsOct 15 2003We present results of our search for collimated ionized winds in bipolar nebulae using the Very Large Array (VLA) and the Australia Telescope Compact Array (ATCA). Our search is motivated by the discovery of an ionized jet in the bipolar nebula M 2-9 ... More
Asymptotic eigenvalue distribution of large Toeplitz matricesAug 23 2007We study the asymptotic eigenvalue distribution of Toeplitz matrices generated by a singular symbol. It has been conjectured by Widom that, for a generic symbol, the eigenvalues converge to the image of the symbol. In this paper we ask how the eigenvalues ... More
Axiomatic Ranking of Network Role SimilarityFeb 18 2011Jun 10 2011A key task in social network and other complex network analysis is role analysis: describing and categorizing nodes according to how they interact with other nodes. Two nodes have the same role if they interact with equivalent sets of neighbors. The most ... More
Quiver Structure of Heterotic ModuliAug 15 2012We analyse the vector bundle moduli arising from generic heterotic compactifications from the point of view of quiver representations. Phenomena such as stability walls, crossing between chambers of supersymmetry, splitting of non-Abelian bundles and ... More
Distinguishing Elliptic Fibrations with AIApr 17 2019May 10 2019We use the latest techniques in machine-learning to study whether from the landscape of Calabi-Yau manifolds one can distinguish elliptically fibred ones. Using the dataset of complete intersections in products of projective spaces (CICY3 and CICY4, totalling ... More
Probing Spin Accumulation induced Magnetocapacitance in a Single Electron TransistorMar 28 2015Jul 07 2015The interplay between spin and charge in solids is currently among the most discussed topics in condensed matter physics. Such interplay gives rise to magneto-electric coupling, which in the case of solids was named magneto-electric effect, as predicted ... More
Oil drop deposition on solid surfaces in mixed polymer-surfactant solutions in relation to hair- and skin-care applicationsMay 27 2019The deposition of oil drops on solid substrates from mixed solutions of surfactants and cationic polymer is investigated. The used anionic surfactants are sodium laurylethersulfate (SLES) and sulfonated methyl esters (SME); the zwitterionic surfactant ... More
Noncommutative Field Theory from twisted Fock spaceMar 31 2006Jun 03 2006We construct a quantum field theory in noncommutative spacetime by twisting the algebra of quantum operators (especially, creation and annihilation operators) of the corresponding quantum field theory in commutative spacetime. The twisted Fock space and ... More
Realization of Woodpile Structure Using Optical Interference HolographyJul 15 2006We report the use of a (4+1)-beam optical interference holography technique to fabricate woodpile structures in photo-resists. The configuration consists of 4 linear polarized side beams arranged symmetrically around a circular polarized central beam ... More
Image RetargetabilityFeb 12 2018Real-world applications could benefit from the ability to automatically retarget an image to different aspect ratios and resolutions, while preserving its visually and semantically important content. However, not all images can be equally well processed ... More
EXPLORE/OC: A Search for Planetary Transits in the Field of NGC 2660Dec 08 2003We present preliminary photometric results of a monitoring study of the open cluster NGC 2660 as part of the EXPLORE/OC project to find planetary transits in Galactic open clusters. Analyzing a total of 21000 stars (3000 stars with photometry to 1% or ... More
Thermodynamics and spin-charge separation of one-dimensional strongly repulsive three-component fermionsMay 09 2011Oct 13 2011The low temperature thermodynamics of one-dimensional strongly repulsive SU(3) fermions in the presence of a magnetic field is investigated via the Yang-Yang thermodynamic Bethe ansatz method. The analytical free energy and magnetic properties of the ... More
kappa-deformed Spacetime From TwistNov 16 2006Apr 03 2008We twist the Hopf algebra of igl(n,R) to obtain the kappa-deformed spacetime coordinates. Coproducts of the twisted Hopf algebras are explicitly given. The kappa-deformed spacetime obtained this way satisfies the same commutation relation as that of the ... More
Image Retargeting by Content-Aware SynthesisMar 26 2014Aug 21 2014Real-world images usually contain vivid contents and rich textural details, which will complicate the manipulation on them. In this paper, we design a new framework based on content-aware synthesis to enhance content-aware image retargeting. By detecting ... More
Holographic Monopole Catalysis of Baryon DecayApr 08 2008Apr 22 2008We study how monopole catalysis of baryon decay is realized in holographic QCD. Physics of monopole catalysis becomes much simpler in holographic description as it occurs due to the violation of the Bianchi identity for the 5D gauge symmetry when magnetic ... More
Chiral microstructures (spirals) fabrication by holographic lithographyAug 02 2005Sep 06 2005We present an optical interference model to create chiral microstructures (spirals) and its realization in photoresist using holographic lithography. The model is based on the interference of six equally-spaced circumpolar linear polarized side beams ... More
Optical studies of carrier and phonon dynamics in Ga_{1-x}Mn_{x}AsApr 13 2005May 03 2005We present a time-resolved optical study of the dynamics of carriers and phonons in Ga_{1-x}Mn_{x}As layers for a series of Mn and hole concentrations. While band filling is the dominant effect in transient optical absorption in low-temperature-grown ... More
Extensions of Enveloping Algebras by Anti-Cocommutative ElementsNov 10 2017Nov 02 2018Anti-cocommutative elements were introduced by Wang, Zhang, Zhuang (2013) in their paper Coassociative Lie Algebras. We use this notion to extend universal enveloping algebras of Lie algebras with regards to their Hopf structure, and see if these connected ... More
Macroscopic Quantum Tunnelling in Rotating Bose-Einstein CondensatesApr 10 2002Apr 12 2002In this paper we investigate the macroscopic quantum tunnelling and the phase coherence property of the rotating Bose-Einstein condensates in both static and dynamic cases by using the mean field theory.
Scale-free networks with tunable degree distribution exponentsJan 31 2004We propose and study a model of scale-free growing networks that gives a degree distribution dominated by a power-law behavior with a model-dependent, hence tunable, exponent. The model represents a hybrid of the growing networks based on popularity-driven ... More
SPIGAN: Privileged Adversarial Learning from SimulationOct 09 2018Feb 18 2019Deep Learning for Computer Vision depends mainly on the source of supervision.Photo-realistic simulators can generate large-scale automatically labeled syntheticdata, but introduce a domain gap negatively impacting performance. We propose anew unsupervised ... More
Multi-Antenna Transmission in Downlink Heterogeneous Cellular Networks under A Threshold-based Mobile Association PolicyOct 26 2016With the recent emergence of 5G era, heterogeneous cellular networks (HCNs) have invoked a popular research interest. In this paper, we provide a comprehensive analysis for multiantenna transmissions in a multi-tier downlink HCN. We first propose a reliability-oriented ... More
Dual User Selection for Security Enhancement in Uplink Multiuser SystemsAug 19 2016This letter proposes a novel dual user selection scheme for uplink transmission with multiple users, where a jamming user and a served user are jointly selected to improve the secrecy performance. Specifically, the jamming user transmits jamming signal ... More
Invariance of Quantum Rings under Ordinary Flops II: A quantum Leray--Hirsch theoremNov 22 2013Feb 14 2016This is the second of a sequence of papers proving the quantum invariance for ordinary flops over an arbitrary smooth base. In this paper, we complete the proof of the invariance of the big quantum rings under ordinary flops of splitting type. To achieve ... More
Value iteration for approximate dynamic programming under convexityFeb 20 2018This paper studies value iteration for infinite horizon contracting Markov decision processes under convexity assumptions and when the state space is uncountable. The original value iteration is replaced with a more tractable form and the fixed points ... More
rlsm: R package for least squares Monte CarloJan 17 2018This short paper briefly describes the implementation of the least squares Monte Carlo method in the rlsm package. This package provides users with an easy manner to experiment with the large amount of R regression tools on any regression basis and reward ... More
Heterotic Bundles on Calabi-Yau Manifolds with Small Picard NumberAug 04 2011We undertake a systematic scan of vector bundles over spaces from the largest database of known Calabi-Yau three-folds, in the context of heterotic string compactification. Specifically, we construct positive rank five monad bundles over Calabi-Yau hypersurfaces ... More
Heterotic Models from Vector Bundles on Toric Calabi-Yau ManifoldsNov 04 2009Dec 11 2009We systematically approach the construction of heterotic E_8 X E_8 Calabi-Yau models, based on compact Calabi-Yau three-folds arising from toric geometry and vector bundles on these manifolds. We focus on a simple class of 101 such three-folds with smooth ... More
Quantum Cohomology under Birational Maps and TransitionsMay 13 2017This is an expanded version of the third author's lecture in String-Math 2015 at Sanya. It summarizes some of our works in quantum cohomology. After reviewing the quantum Lefschetz and quantum Leray--Hirsch, we discuss their applications to the functoriality ... More
Nonlinear quantum interferometry with Bose condensed atomsOct 21 2011Oct 30 2011In quantum interferometry, it is vital to control and utilize nonlinear interactions for achieving high-precision measurements. Attribute to their long coherent time and high controllability, ultracold atoms including Bose condensed atoms have been widely ... More
Pair density wave, charge density wave and vortex in high Tc cupratesFeb 08 2018Mar 02 2018A recent scanning tunneling microscopy (STM) experiment reports the observation of charge density wave (CDW) with period of approximately 8a in the halo region surrounding the vortex core, in striking contrast to the approximately period 4a CDW that are ... More
Quantum coherence of double-well BEC: a SU(2)-coherent-state path-integral approachApr 19 2001Feb 21 2003Macroscopic quantum coherence of Bose gas in a double-well potential is studied based on SU(2)-coherent-state path-integral. The ground state and fluctuations around it can be obtained by this method. In this picture, one can obtain macroscopic quantum ... More
Non-orthogonal Multiple Access Assisted Multi-Region GeocastNov 29 2017This work proposes a novel location-based multi-group multicast framework which is termed as non-orthogonal multiple access (NOMA) assisted multi-region geocast. This novel spectrum sharing framework exploits the NOMA technology to realize the simultaneous ... More
Estimation of solar irradiance using ground-based whole sky imagersJun 08 2016Ground-based whole sky imagers (WSIs) can provide localized images of the sky of high temporal and spatial resolution, which permits fine-grained cloud observation. In this paper, we show how images taken by WSIs can be used to estimate solar radiation. ... More
WAHRSIS: A Low-cost, High-resolution Whole Sky Imager With Near-Infrared CapabilitiesMay 21 2016Cloud imaging using ground-based whole sky imagers is essential for a fine-grained understanding of the effects of cloud formations, which can be useful in many applications. Some such imagers are available commercially, but their cost is relatively high, ... More
Flops, motives and invariance of quantum ringsAug 15 2006May 16 2007For ordinary flops, the correspondence defined by the graph closure is shown to give equivalence of Chow motives and to preserve the Poincar\'e pairing. In the case of simple ordinary flops, this correspondence preserves the big quantum cohomology ring ... More
Invariance of Quantum Rings under Ordinary Flops I: Quantum corrections and reduction to local modelsSep 26 2011Feb 14 2016This is the first of a sequence of papers proving the quantum invariance under ordinary flops over an arbitrary smooth base. In this first part, we determine the defect of the cup product under the canonical correspondence and show that it is corrected ... More
Heterotic Model Building: 16 Special ManifoldsSep 01 2013May 13 2014We study heterotic model building on 16 specific Calabi-Yau manifolds constructed as hypersurfaces in toric four-folds. These 16 manifolds are the only ones among the more than half a billion manifolds in the Kreuzer-Skarke list with a non-trivial first ... More
Efficiently estimating small p-values in permutation tests using importance sampling and cross-entropy methodJul 30 2016Permutation tests are commonly used for estimating p-values from statistical hypothesis testing when the sampling distribution of the test statistic under the null hypothesis is not available or unreliable for finite sample sizes. One critical challenge ... More
Tracking in Urban Traffic Scenes from Background Subtraction and Object DetectionMay 15 2019In this paper, we propose to combine detections from background subtraction and from a multiclass object detector for multiple object tracking (MOT) in urban traffic scenes. These objects are associated across frames using spatial, colour and class label ... More
Diffractive Vector Photoproduction using Holographic QCDApr 25 2018We discuss diffractive photon-production of vector mesons in holographic QCD. At large $\sqrt{s}$, the QCD scattering amplitudes are reduced to the scattering of pair of dipoles exchanging a closed string or a pomeron. We use the holographic construction ... More
The electronic instabilities of the Iron-based superconductors: a variational Monte-Carlo studyJul 15 2010Apr 11 2011We report the first variational Monte Carlo (VMC) study of the iron-based superconductors. We use realistic band structures, and the ordering instabilities/variational ansatzs are suggested by previous functional renormalization group calculations. We ... More
Convolutional-Recurrent Neural Networks for Speech EnhancementMay 02 2018We propose an end-to-end model based on convolutional and recurrent neural networks for speech enhancement. Our model is purely data-driven and does not make any assumptions about the type or the stationarity of the noise. In contrast to existing methods ... More
Towards $A + B$ theory in conifold transitions for Calabi-Yau threefoldsFeb 11 2015Sep 20 2017For projective conifold transitions between Calabi-Yau threefolds $X$ and $Y$, with $X$ close to $Y$ in the moduli, we show that the combined information provided by the $A$ model (Gromov--Witten theory in all genera) and $B$ model (variation of Hodge ... More
Extending Enveloping Algebras via Anti-Cocommutative ElementsMay 29 2017Jan 30 2018Anti-cocommutativity was introduced by Wang, Zhuang, Zhang (2013) in their paper Coassociative Lie algebras. Since universal enveloping algebras of Lie algebras are connected Hopf algebras, we extend enveloping algebras using the notion of anti-cocommutative ... More
Convex function approximations for Markov decision processesDec 04 2017Feb 20 2018This paper studies function approximation for finite horizon discrete time Markov decision processes under certain convexity assumptions. Uniform convergence of these approximations on compact sets is proved under several sampling schemes for the driving ... More
Spontaneous Subtle Expression Detection and Recognition based on Facial StrainJun 09 2016Optical strain is an extension of optical flow that is capable of quantifying subtle changes on faces and representing the minute facial motion intensities at the pixel level. This is computationally essential for the relatively new field of spontaneous ... More
Imaging the Nanoscale Band Structure of Topological SbNov 07 2013Many promising building blocks of future electronic technology - including non-stoichiometric compounds, strongly correlated oxides, and strained or patterned films - are inhomogeneous on the nanometer length scale. Exploiting the inhomogeneity of such ... More
EXPLORE/OC: A Search for Planetary Transits in the Field of the Southern Open Cluster NGC 6208Dec 16 2003The EXPLORE Project expanded in 2003 to include a campaign to monitor rich southern open clusters for transits of extrasolar planets (EXPLORE/OC). In May and June 2003, we acquired precise, high-cadence photometry of the second open cluster in our campaign, ... More
Searching for Planetary Transits in Galactic Open Clusters: EXPLORE/OCSep 27 2004Dec 07 2004Open clusters potentially provide an ideal environment for the search for transiting extrasolar planets since they feature a relatively large number of stars of the same known age and metallicity at the same distance. With this motivation, over a dozen ... More
Constraining the Synopsys Pin Access Checker Utility for Improved Standard Cells Library Verification FlowMay 25 2018While standard cell layouts are drawn with minimum design rules for maximum benefit of design area shrinkage, the complicated design rules begin to cause difficulties with signal routes accessing the pins in standard cell layouts. Multiple design iterations ... More