Search results for "Linear Algebra"

showing 10 items of 552 documents

Characterization of greedy bases in Banach spaces

2017

Abstract We shall present a new characterization of greedy bases and 1-greedy bases in terms of certain functionals defined using distances to one dimensional subspaces generated by the basis. We also introduce a new property that unifies the notions of unconditionality and democracy and allows us to recover a better dependence on the constants.

Numerical AnalysisPure mathematicsProperty (philosophy)Basis (linear algebra)Applied MathematicsGeneral Mathematics010102 general mathematicsBanach space010103 numerical & computational mathematicsCharacterization (mathematics)01 natural sciencesLinear subspaceFunctional Analysis (math.FA)Mathematics - Functional AnalysisFOS: MathematicsProperty a0101 mathematicsAnalysisMathematics
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High-quality computational tools for linear-algebra problems in FEM electromagnetic simulation [EM Programmer's Notebook]

2004

A key ingredient of finite-element analysis programs is the linear-algebra solver, typically either a linear-system solver or an eigensolver. The first part of This work tries to justify why it is important to have recourse to publicly available software for addressing this part of the computation. A number of libraries are mentioned as successful examples that exhibit a series of desirable qualities. Although some of these libraries force the programmer to somewhat change the programming style and may be difficult to learn, the benefits usually pay off the extra effort. The second part of the paper describes one of these libraries in some detail, namely SLEPc, the Scalable Library for Eige…

Numerical linear algebraTheoretical computer sciencebusiness.industryComputer sciencemedia_common.quotation_subjectSolverCondensed Matter Physicscomputer.software_genreProgramming styleSoftwareLinear algebraScalabilityKey (cryptography)Electrical and Electronic EngineeringSoftware engineeringbusinessProgrammercomputermedia_commonIEEE Antennas and Propagation Magazine
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State-of-the-art density matrix renormalization group and coupled cluster theory studies of the nitrogen binding curve.

2004

We study the nitrogen binding curve with the density matrix renormalization group (DMRG) and single-reference and multireference coupled cluster (CC) theory. Our DMRG calculations use up to 4000 states and our single-reference CC calculations include up to full connected hextuple excitations. Using the DMRG, we compute an all-electron benchmark nitrogen binding curve, at the polarized, valence double-zeta level (28 basis functions), with an estimated accuracy of 0.03mE_h. We also assess the performance of more approximate DMRG and CC theories across the nitrogen curve. We provide an analysis of the relative strengths and merits of the DMRG and CC theory under different correlation condition…

Numerical linear algebraValence (chemistry)Density matrix renormalization groupGeneral Physics and Astronomychemistry.chemical_elementBasis functioncomputer.software_genreNitrogenCoupled clusterchemistryMatrix algebraQuantum mechanicsCondensed Matter::Strongly Correlated ElectronsPhysical and Theoretical ChemistrycomputerGroup theoryThe Journal of chemical physics
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Sustainable Method Using Filtering Techniques for a Fermentation Process State Estimation

2020

Winemaking is concerned about sustainable energy availability that implies new methods for process monitoring and control. The aim of this paper is to realize a comparative analysis of the possibilities offered using estimation techniques, balances, and filtering techniques such as the Kalman filter (KF) and the extended Kalman filter (EKF), to obtain indirect information about the alcoholic fermentation process during winemaking. Thus, an estimation solution of the process variables in the exponential growing phase is proposed, using an extended observer. In addition, two estimation solutions of this process with the EKF and an estimation of the decay phase of the fermentation process are …

Observer (quantum physics)Computer science020209 energyGeography Planning and DevelopmentTJ807-83002 engineering and technology010501 environmental sciencesManagement Monitoring Policy and LawTD194-19501 natural sciencesRenewable energy sourcesExtended Kalman filterControl theory0202 electrical engineering electronic engineering information engineeringGE1-350state estimation0105 earth and related environmental sciencesEnvironmental effects of industries and plantsBasis (linear algebra)Renewable Energy Sustainability and the EnvironmentProcess (computing)Kalman filterFilter (signal processing)batch fermentation processExponential functionEnvironmental sciencessustainable control systemNorm (mathematics)Sustainability
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Minor Losses and Best Manifold Position in the Optimal Design of Paired Sloped Drip Laterals

2018

Optimal design0208 environmental biotechnologyMinor (linear algebra)Soil ScienceGeometry04 agricultural and veterinary sciences02 engineering and technologyDrip irrigation020801 environmental engineeringlaw.inventionlawPosition (vector)040103 agronomy & agriculture0401 agriculture forestry and fisheriesEnvironmental scienceAgronomy and Crop ScienceManifold (fluid mechanics)Irrigation and Drainage
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Designing Precoding and Receive Matrices for Interference Alignment in MIMO Interference Channels

2017

Interference is a key bottleneck in wireless communication systems. Interference alignment is a management technique that align interference from other transmitters in the least possibly dimension subspace at each receiver and provides the remaining dimensions for free interference signal. An uncoordinated interference is an example of interference which cannot be aligned coordinately with interference from coordinated part; consequently, the performance of interference alignment approaches are degraded. In this paper, we propose a rank minimization method to enhance the performance of interference alignment in the presence of uncoordinated interference sources. Firstly, to obtain higher mu…

Optimization problemRank (linear algebra)Computer scienceComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSMIMO020206 networking & telecommunications020302 automobile design & engineering02 engineering and technologyTopologyInterference (wave propagation)PrecodingMultiplexing0203 mechanical engineeringDimension (vector space)Interference (communication)0202 electrical engineering electronic engineering information engineeringInterference alignmentComputer Science::Information TheoryCommunication channelGLOBECOM 2017 - 2017 IEEE Global Communications Conference
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Static output-feedback control under information structure constraints

2013

An important challenge in the static output-feedback control context is to provide an isolated gain matrix possessing a zero-nonzero structure, mainly in problems presenting information structure constraints. Although some previous works have contributed some relevant results to this issue, a fully satisfactory solution has not yet been achieved up to now. In this note, by using a Linear Matrix Inequality approach and based on previous results given in the literature, we present an e cient methodology which permits to obtain an isolated static output-feedback gain matrix having, simultaneously, a zero-nonzero structure imposed a priori. Peer Reviewed

Output feedbackAutomatic controlLMIs:Informàtica::Automàtica i control [Àrees temàtiques de la UPC]:Matemàtiques i estadística::Anàlisi numèrica::Mètodes numèrics [Àrees temàtiques de la UPC]:15 Linear and multilinear algebra; matrix theory [Classificació AMS]Information structureControl (management):15 Linear and multilinear algebra [Classificació AMS]Structure (category theory)Linear matrix inequalityContext (language use)Information structure constraintsOutput-feedback controlMatrius (Matemàtica)Control automàticMatrix (mathematics)Control and Systems EngineeringControl theoryInformation structure constraints; LMIs; Output-feedback controlmatrix theoryA priori and a posterioriElectrical and Electronic EngineeringMatrix inequalitiesMathematics
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Neutral and charged pion properties under strong magnetic fields in the NJL model

2019

In the framework of the Nambu-Jona-Lasino (NJL) model, we study the effect of an intense external uniform magnetic field on neutral and charged pion masses and decay form factors. In particular, the treatment of charged pions is carried out on the basis of the Ritus eigenfunction approach to magnetized relativistic systems. Our analysis shows that in the presence of the magnetic field three and four nonvanishing pion-to-vacuum hadronic form factors can be obtained for the case of the neutral and charged pions, respectively. As expected, it is seen that for nonzero magnetic field the π⁰ meson can still be treated as a pseudo Nambu-Goldstone boson, and consequently the corresponding form fact…

Particle physicsMesonHigh Energy Physics::LatticeEffective field theoryHadronNuclear TheoryFOS: Physical sciences01 natural sciencesLeptonic semileptonic & radiative decaysHadronic decaysHigh Energy Physics - Phenomenology (hep-ph)Pion0103 physical sciencesNonperturbative effects in field theory010306 general physicsCiencias ExactasBosonPhysicsBasis (linear algebra)010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyForm factorsEigenfunctionMagnetic fieldHigh Energy Physics - PhenomenologyHigh Energy Physics::Experiment
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Prediction of tyrosinase inhibition activity using atom-based bilinear indices.

2007

A set of novel atom-based molecular fingerprints is proposed based on a bilinear map similar to that defined in linear algebra. These molecular descriptors (MDs) are proposed as a new means of molecular parametrization easily calculated from 2D molecular information. The nonstochastic and stochastic molecular indices match molecular structure provided by molecular topology by using the kth nonstochastic and stochastic graph-theoretical electronic-density matrices, M(k) and S(k), respectively. Thus, the kth nonstochastic and stochastic bilinear indices are calculated using M(k) and S(k) as matrix operators of bilinear transformations. Chemical information is coded by using different pair com…

PharmacologyMelaninsQuantitative structure–activity relationshipStochastic ProcessesSeries (mathematics)Molecular StructureChemistryMonophenol MonooxygenaseOrganic ChemistryBilinear interpolationLinear discriminant analysisBiochemistryStructure-Activity RelationshipDiscriminantModels ChemicalComputational chemistryMolecular descriptorDrug DiscoveryLinear algebraMolecular MedicineComputer SimulationGeneral Pharmacology Toxicology and PharmaceuticsBilinear mapEnzyme InhibitorsBiological systemChemMedChem
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Recent advances in intelligent-based structural health monitoring of civil structures

2018

This survey paper deals with the structural health monitoring systems on the basis of methodologies involving intelligent techniques. The intelligent techniques are the most popular tools for damage identification in terms of high accuracy, reliable nature and the involvement of low cost. In this critical survey, a thorough analysis of various intelligent techniques is carried out considering the cases involved in civil structures. The importance and utilization of various intelligent tools to be mention as the concept of fuzzy logic, the technique of genetic algorithm, the methodology of neural network techniques, as well as the approaches of hybrid methods for the monitoring of the struct…

Physics and Astronomy (miscellaneous)Computer science020101 civil engineering02 engineering and technologyMachine learningcomputer.software_genreFuzzy logiclcsh:Technology0201 civil engineering0203 mechanical engineeringManagement of Technology and InnovationGenetic algorithmlcsh:ScienceEngineering (miscellaneous)Basis (linear algebra)Artificial neural networkbusiness.industrylcsh:TIdentification (information)020303 mechanical engineering & transportsCritical surveylcsh:QArtificial intelligenceStructural health monitoringbusinesscomputer
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