Search results for " Computer Science"

showing 10 items of 3983 documents

Unique continuation of the normal operator of the x-ray transform and applications in geophysics

2020

We show that the normal operator of the X-ray transform in $\mathbb{R}^d$, $d\geq 2$, has a unique continuation property in the class of compactly supported distributions. This immediately implies uniqueness for the X-ray tomography problem with partial data and generalizes some earlier results to higher dimensions. Our proof also gives a unique continuation property for certain Riesz potentials in the space of rapidly decreasing distributions. We present applications to local and global seismology. These include linearized travel time tomography with half-local data and global tomography based on shear wave splitting in a weakly anisotropic elastic medium.

FOS: Physical sciencesx-ray transformSpace (mathematics)01 natural sciencesTheoretical Computer SciencePhysics - GeophysicsContinuationtomografiaClassical Analysis and ODEs (math.CA)FOS: MathematicsNormal operatorUniqueness0101 mathematicsAnisotropyMathematical PhysicsMathematicsX-ray transformgeophysicsApplied Mathematics010102 general mathematicsMathematical analysisgeofysiikkaShear wave splittingInverse problemFunctional Analysis (math.FA)Geophysics (physics.geo-ph)Computer Science ApplicationsMathematics - Functional Analysis010101 applied mathematicsMathematics - Classical Analysis and ODEsSignal ProcessingInverse Problems
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Estimation des performances, test et contrôle des systèmes cyber-physiques employant des réseaux de communication non idéaux

2020

Wireless technology is a key enabler of the promises of Industry 4.0 (Smart Manufacturing). As such, wireless technology will be adopted as a principal mode of communication within the factory beginning with the factory enterprise and eventually being adopted for use within the factory workcell. Factory workcell communication has particular requirements on latency, reliability, scale, and security that must first be met by the wireless communication technology used. Wireless is considered a non-ideal form of communication in that when compared to its wired counterparts, it is considered less reliable (lossy) and less secure. These possible impairments lead to delay and loss of data in indus…

Fabrication intelligenteIndustrial wireless testbed[INFO.INFO-TS] Computer Science [cs]/Signal and Image ProcessingSmart manufacturingApprentissage automatiqueSystems modelingGraph databaseBase de données graphe[INFO.INFO-TS]Computer Science [cs]/Signal and Image ProcessingMachine learningIndustrial wirelessModelisation systémeCommunications sans fil industrielBanc d'essai sans fil industriel
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Growth of two-dimensional Au patches in graphene pores: A density-functional study

2017

Inspired by recent studies of various two-dimensional (2D) metals such as Au, Fe and Ag, we study the growth of two-dimensional gold patches in graphene pores by density-functional theory. We find that at room temperature gold atoms diffuse readily on top of both graphene and two-dimensional gold with energy barriers less than $0.5$ eV. Furthermore, gold atoms move without barriers from the top of graphene to its edge and from the top of 2D gold to its edge. The energy barriers are absent even at the interface of 2D gold and graphene, so that the gold atoms move effortlessly across the interface. We hope our demonstration for the propensity of diffusing gold atoms to grow 2D gold patches in…

FabricationMaterials scienceGeneral Computer ScienceFOS: Physical sciencesGeneral Physics and AstronomyNanotechnology02 engineering and technology01 natural scienceslaw.inventiontwo-dimensional metalsgraphene poresgold nanostructureslawMesoscale and Nanoscale Physics (cond-mat.mes-hall)0103 physical sciencesGeneral Materials Science010306 general physicsCondensed Matter - Materials Scienceta114Condensed Matter - Mesoscale and Nanoscale PhysicsGrapheneMaterials Science (cond-mat.mtrl-sci)General Chemistry021001 nanoscience & nanotechnologyComputational MathematicsMechanics of MaterialsDensity functional theory0210 nano-technologydensity-functional modelingGraphene nanoribbonsComputational Materials Science
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Automatic landmark detection and 3D Face data extraction

2017

Abstract This paper contributes to 3D facial synthesis by presenting a novel method for parameterization using Landmark Point detection. The approach presented aims at improving facial recognition even in varying facial expressions, and missing data in 3D facial models. As such, the prime objective was to develop an automatically embedded process that can detect any frontal face in 3D face recognition systems, with face segmentation and surface curvature information. Using the hybrid interpolation method, experiments on facial landmarks were performed on 4950 images from Face Recognition Grand Challenge database (FRGC). Distinctive facial landmarks from the nose–tips, Limits mouth and two e…

Face hallucinationGeneral Computer ScienceComputer sciencebusiness.industry05 social sciencesComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION050301 educationIterative closest pointPattern recognition02 engineering and technologyLandmark pointFace Recognition Grand ChallengeFacial recognition systemTheoretical Computer SciencePoint distribution modelModeling and Simulation0202 electrical engineering electronic engineering information engineeringThree-dimensional face recognition020201 artificial intelligence & image processingComputer visionArtificial intelligenceFace detectionbusiness0503 educationJournal of Computational Science
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The General Routing Problem polyhedron: Facets from the RPP and GTSP polyhedra

1998

[EN] In this paper we study the polyhedron associated with the General Routing Problem (GRP). This problem, first introduced by Orloff in 1974, is a generalization of both the Rural Postman Problem (RPP) and the Graphical Traveling Salesman Problem (GTSP) and, thus, is NP -hard. We describe a formulation of the problem such that from every non-trivial facet-inducing inequality for the RPP and GTSP polyhedra, we obtain facet-inducing inequalities for the GRP polyhedron, We describe a new family of facet-inducing inequalities for the GRP, the honeycomb constraints, which seem to be very useful for solving GRP and RPP instances. Finally, new classes of facets obtained by composition of facet-i…

Facet (geometry)Information Systems and ManagementGeneral Computer ScienceGeneralizationHoneycomb (geometry)Facets of polyhedraGraph theoryManagement Science and Operations ResearchTravelling salesman problemIndustrial and Manufacturing EngineeringRural Postman ProblemGeneral Routing ProblemCombinatoricsPolyhedronModeling and SimulationGraphical Traveling Salesman ProblemCombinatorial optimizationMathematics::Metric GeometryRouting (electronic design automation)MATEMATICA APLICADAMathematicsRouting
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Remote heart rate variability for emotional state monitoring

2018

International audience; Several researches have been conducted to recognize emotions using various modalities such as facial expressions , gestures, speech or physiological signals. Among all these modalities, physiological signals are especially interesting because they are mainly controlled by the autonomic nervous system. It has been shown for example that there is an undeniable relationship between emotional state and Heart Rate Variability (HRV). In this paper, we present a methodology to monitor emotional state from physiological signals acquired remotely. The method is based on a remote photoplethysmography (rPPG) algorithm that estimates remote Heart Rate Variability (rHRV) using a …

Facial expressionModalities[ INFO.INFO-TS ] Computer Science [cs]/Signal and Image Processing[INFO.INFO-TS] Computer Science [cs]/Signal and Image ProcessingComputer scienceSpeech recognition020208 electrical & electronic engineering0206 medical engineering[INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV]02 engineering and technology[ INFO.INFO-CV ] Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV]020601 biomedical engineeringSignal[INFO.INFO-CV] Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV][INFO.INFO-TS]Computer Science [cs]/Signal and Image ProcessingFeature (computer vision)Frequency domainPhotoplethysmogram0202 electrical engineering electronic engineering information engineeringHeart rate variabilityGesture
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Good Old-Fashioned Artificial Consciousness and the Intermediate Level Fallacy

2018

Recently, there has been considerable interest and effort to the possibility to design and implement conscious robots, i.e., the chance that a robot may have subjective experiences. However, typical approaches as the global workspace, information integration, enaction, cognitive mechanisms, embodiment, i.e., the Good Old-Fashioned Artificial Consciousness, henceforth, GOFAC, share the same conceptual framework. In this paper, we discuss GOFAC's basic tenets and their implication for AI and Robotics. In particular, we point out the intermediate level fallacy as the central issue affecting GOFAC. Finally, we outline a possible alternative conceptual framework towards robot consciousness.

Fallacyartificial consciousnessComputer sciencemedia_common.quotation_subjectlcsh:Mechanical engineering and machinerymachine consciousnessArtificial consciousness050105 experimental psychologylcsh:QA75.5-76.95Enactivism03 medical and health sciences0302 clinical medicineArtificial IntelligenceHypothesis and Theory0501 psychology and cognitive scienceslcsh:TJ1-1570media_commonrobot consciousness; machine consciousness; artificial consciousness; synthetic phenomenology; robot self-awarenessrobot consciousneartificial consciousneCognitive scienceSettore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniRobotics and AIIntegrated information theory05 social sciencesHard problem of consciousnessComputer Science Applicationsrobot self-awarenessConceptual frameworkRobotlcsh:Electronic computers. Computer scienceConsciousnessrobot consciousnesssynthetic phenomenologymachine consciousne030217 neurology & neurosurgeryFrontiers in Robotics and AI
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Toward Optimal LSTM Neural Networks for Detecting Algorithmically Generated Domain Names

2021

Malware detection is a problem that has become particularly challenging over the last decade. A common strategy for detecting malware is to scan network traffic for malicious connections between infected devices and their command and control (C&C) servers. However, malware developers are aware of this detection method and begin to incorporate new strategies to go unnoticed. In particular, they generate domain names instead of using static Internet Protocol addresses or regular domain names pointing to their C&C servers. By using a domain generation algorithm, the effectiveness of the blacklisting of domains is reduced, as the large number of domain names that must be blocked g…

Feature engineeringGeneral Computer ScienceArtificial neural networkComputer sciencebusiness.industrymalwareDeep learningGeneral EngineeringDeep learningdomain generation algorithmscomputer.software_genreBlacklistDomain (software engineering)TK1-9971ServerMalwareGeneral Materials ScienceNetwork performanceArtificial intelligenceData miningElectrical engineering. Electronics. Nuclear engineeringbusinessLSTMcomputerIEEE Access
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Quotients of Fermat curves and a Hecke character

2005

AbstractWe explicitly identify infinitely many curves which are quotients of Fermat curves. We show that some of these have simple Jacobians with complex multiplication by a non-cyclotomic field. For a particular case we determine the local zeta functions with two independent methods. The first uses Jacobi sums and the second applies the general theory of complex multiplication, we verify that both methods give the same result.

Fermat's Last TheoremDiscrete mathematicsAlgebra and Number TheoryMathematics::Number TheoryApplied MathematicsGeneral EngineeringComplex multiplicationFermat's theorem on sums of two squaresComplex multiplicationField (mathematics)Wieferich primeFermat's factorization methodHecke characterHecke charactersTheoretical Computer Sciencesymbols.namesakeJacobi sumsSimple (abstract algebra)Fermat curvessymbolsEngineering(all)MathematicsFinite Fields and Their Applications
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Optical sectioning microscopy through single-shot Lightfield protocol

2020

Optical sectioning microscopy is usually performed by means of a scanning, multi-shot procedure in combination with non-uniform illumination. In this paper, we change the paradigm and report a method that is based in the light field concept, and that provides optical sectioning for 3D microscopy images after a single-shot capture. To do this we fi rst capture multiple orthographic perspectives of the sample by means of Fourier-domain integral microscopy (FiMic). The second stage of our protocol is the application of a novel refocusing algorithm that is able to produce optical sectioning in real time, and with no resolution worsening, in the case of sparse f luorescent samples.We provide the…

FiMicGeneral Computer ScienceOptical sectioningComputer scienceComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION02 engineering and technology3d microscopy01 natural sciences010309 opticsOptics0103 physical sciencesMicroscopyGeneral Materials ScienceProtocol (object-oriented programming)Fourier integral microscopebusiness.industryResolution (electron density)Orthographic projectionGeneral EngineeringSingle shotfourier lightfield microscopeGPU computingÒptica021001 nanoscience & nanotechnologySample (graphics)Microscòpialightfield microscopeoptical sectioninglcsh:Electrical engineering. Electronics. Nuclear engineering0210 nano-technologybusinesslcsh:TK1-9971
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