Search results for "Graph theory"

showing 10 items of 784 documents

A Novel Iris Recognition System based on Micro-Features

2007

In this paper a novel approach for iris recognition system based on iris micro-features is proposed. The proposed system follows the minutiae based approach developed for fingerprint recognition systems. The proposed system uses four iris microfeatures, considered as minutiae, for identification. The individualized characteristics are nucleus, collarette, valleys and radius. Iris recognition is divided in three main phases: image preprocessing, micro-features extraction and matching. The algorithm has been tested on CASIA v1.0 iris image database obtaining an high accuracy. The obtained experimental results have been analyzed and compared with the Daugman based approach.

MinutiaeMatching (graph theory)Biometricsbusiness.industryIris recognitionFeature extractionComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISIONPattern recognitionFingerprint recognitionComputingMethodologies_PATTERNRECOGNITIONGeographyiris micro-characteristIcs recognition systemPreprocessorComputer visionIRIS (biosensor)Artificial intelligencebusiness
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Performance evaluation of simple fingerprint minutiae extraction algorithm using crossing number on valley structure

2008

In fingerprint recognition system, performance of fingerprint feature extraction algorithm is important. We use visual analysis to evaluate this performance. 100 respondents fill a questionnaire consisting of 30 images from fingerprint feature extraction process. We get 12,3 % minutiae points missed by this algorithm. With BOZORTH3 minutiae matching algorithm, the distribution of matching score of 80-fingerprint images are presented and we obtain EER 5.89 % at threshold value 180.

MinutiaeMatching (graph theory)Computer sciencebusiness.industryFeature extractionPattern recognitionImage segmentationFingerprint recognitionFingerprintComputer visionAlgorithm designArtificial intelligencebusinessBlossom algorithm2008 International Conference on Innovations in Information Technology
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Fingerprint image enhancement using directional morphological filter

2005

Fingerprint images quality enhancement is a topic phase to ensure good performance in an automatic fingerprint identification system (AFIS) based on minutiae matching. In this paper a new fingerprint enhancement algorithm based on morphological filter is introduced. The algorithm is based on three steps: directional decomposition, morphological filter and composition. The performance of the proposed approach has been evaluated on two sets of images: the first one is DB3 database from Fingerprint Verification Competition (FVC) and the second one is self collected using an optical scanner

MinutiaeScannerMatching (graph theory)business.industryComputer scienceImage qualityComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISIONPhase (waves)Fingerprint Verification CompetitionPattern recognitionImage segmentationFingerprintBiometrics | Algorithms | fingerprint orientationArtificial intelligencebusiness
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A Highly Flexible Trajectory Model Based on the Primitives of Brownian Fields—Part I: Fundamental Principles and Implementation Aspects

2015

A fundamental drawback of synthetic mobility models is that the spatial configuration of the path is determined by the temporal features of the mobile station (MS), such as its speed. This is, however, not true in reality. This first part of our paper establishes a new approach for generating fully spatial random trajectory (mobility) models to which different speed scenarios can be applied. We employ the new approach to the proposal of a highly flexible trajectory model based on the primitives (integrals) of Brownian fields (BFs). We construct a drifted partial random bridge from a given starting point to a random terminating point in the 2D plane. If the bridge is partially established, a…

Mobility modelStochastic processApplied MathematicsMobile ad hoc networkTopologyComputer Science ApplicationsMobile stationPath (graph theory)TrajectoryPoint (geometry)Electrical and Electronic EngineeringBrownian motionSimulationMathematicsIEEE Transactions on Wireless Communications
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Verification of scope-dependent hierarchical state machines

2008

AbstractA hierarchical state machine (Hsm) is a finite state machine where a vertex can either expand to another hierarchical state machine (box) or be a basic vertex (node). Each node is labeled with atomic propositions. We study an extension of such model which allows atomic propositions to label also boxes (Shsm). We show that Shsms can be exponentially more succinct than Shsms and verification is in general harder by an exponential factor. We carefully establish the computational complexity of reachability, cycle detection, and model checking against general Ltl and Ctl specifications. We also discuss some natural and interesting restrictions of the considered problems for which we can …

Model checkingVertex (graph theory)Model checkingFinite-state machineComputational complexity theoryTemporal logicAutomataTheoretical Computer ScienceComputer Science ApplicationsSuccinctnessComputational Theory and MathematicsReachabilityComputer Science::Logic in Computer ScienceHierarchical state machinesTemporal logicCycle detectionAlgorithmComputer Science::DatabasesMathematicsInformation SystemsInformation and Computation
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Chemistry Explained by Topology: An Alternative Approach

2011

Molecular topology can be considered an application of graph theory in which the molecular structure is characterized through a set of graph-theoretical descriptors called topological indices. Molecular topology has found applications in many different fields, particularly in biology, chemistry, and pharmacology. The first topological index was introduced by H. Wiener in 1947 [1]. Although its very first application was the prediction of the boiling points of the alkanes, the Wiener index has demonstrated since then a predictive capability far beyond that. Along with the Wiener index, in this paper we focus on a few pioneering topological indices, just to illustrate the connection between p…

Molecular StructureChemistry PhysicalChemistryOrganic ChemistryGraph theoryGeneral MedicineWiener indexBiologyTopologyBiomechanical PhenomenaComputer Science ApplicationsConnection (mathematics)Set (abstract data type)Structure-Activity RelationshipModels ChemicalTopological indexAlkanesDrug DiscoveryQuantum TheoryChemistry (relationship)Focus (optics)Topology (chemistry)Combinatorial Chemistry & High Throughput Screening
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Kinetic energy and radial momentum distribution of hydrogen and oxygen atoms of water confined in silica hydrogel in the temperature interval 170–325…

2019

Water is an ubiquitous liquid and it is necessary for life;. Studies on water are therefore of obvious scientific and .... technological relevance. In view of its peculiar physicalproperties (the so-called water anomalies, particularly relevant at low temperatures [1]), studies on water structureand dynamics in ample temperature intervals, covering also the supercooling region, have attracted much interest in recent years. In particular, studies focused on the supercooled phase are important in order to test theories and hypotheses[2,3], including the liquid-liquid phase transition hypothesis [4-6] and the related fragile-to-strong crossover observed inwater confined in silica matrices and …

Momentum (technical analysis)Materials scienceDistribution (number theory)HydrogenSettore FIS/07neutron scatteringGeneral Physics and Astronomychemistry.chemical_elementKinetic energySettore FIS/07 - Fisica Applicata(Beni Culturali Ambientali Biol.e Medicin)Oxygen atomchemistryLiquid-Liquid transitionSupercooled confined waterInterval (graph theory)Atomic physics
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Star-free trace languages

1992

Abstract Generalizing a classical result of Schutzenberger to free partially commutative monoids, we prove that the family of star-free trace languages coincides with the family of aperiodic trace languages.

MonoidPure mathematicsGeneral Computer ScienceAbstract family of languagesComputer Science::Computation and Language (Computational Linguistics and Natural Language and Speech Processing)Star (graph theory)Cone (formal languages)Theoretical Computer ScienceTrace (semiology)Aperiodic graphFormal languageComputer Science::Programming LanguagesCommutative propertyMathematicsComputer Science(all)Theoretical Computer Science
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VIBPACK: A package to treat multidimensional electron-vibrational molecular problems with application to magnetic and optical properties

2018

We present a FORTRAN code based on a new powerful and efficient computational approach to solve multidimensional dynamic Jahn-Teller and pseudo Jahn-Teller problems. This symmetry-assisted approach constituting a theoretical core of the program is based on the full exploration of the point symmetry of the electronic and vibrational states. We also report some selected examples of increasing complexity aimed to display the theoretical background as well as the advantages and capabilities of the program to evaluate of the energy pattern, magnetic and optical properties of large multimode vibronic systems. © 2018 Wiley Periodicals, Inc.

Multi-mode optical fiberComputer scienceFortran02 engineering and technologyGeneral ChemistryElectron010402 general chemistry021001 nanoscience & nanotechnology01 natural sciencesSymmetry (physics)0104 chemical sciencesComputational scienceComputational MathematicsVibronic couplingCore (graph theory)Code (cryptography)Condensed Matter::Strongly Correlated Electrons0210 nano-technologycomputerEnergy (signal processing)computer.programming_languageJournal of Computational Chemistry
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ESE. Estudios sobre educación

2021

espanolEste estudio pretende avanzar en la comprension de la relacion entre el profesor y el estudiante universitario con el objetivo de mejorar el rendimiento de los estudiantes. Se articula sobre tres ejes: el enfoque de rendimiento del estudiante, la relacion entre diversos aspectos del profesor y, fi nalmente, el efecto de estos aspectos sobre el rendimiento del estudiante. Los resultados obtenidos de una muestra de 45 profesores y 932 estudiantes muestran que la orientacion al estudiante por parte del profesor afecta al aprendizaje percibido y a la satisfaccion del estudiante. Se alcanzan otros interesantes resultados que permiten establecer ciertas conclusiones e implicaciones. Englis…

Multilevel modelsBurnout/engagementrelación profesor-alumnomotivación del rendimientoOrientación del profesorOrientation (graph theory)conducta del profesorEducationTeachers' orientationorientación pedagógicaestudianteenseñanza superiorSEMComputingMilieux_COMPUTERSANDEDUCATIONOrientación del estudianteModelos multinivelStudent orientationlcsh:LPsychologyHumanitiesactitud hacia el trabajoUniversity teachers and studentslcsh:EducationProfesor y estudiante universitarioEstudios sobre Educación
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