Search results for "FUNCTIONAL"

showing 10 items of 4822 documents

Disorder and interactions in systems out of equilibrium : the exact independent-particle picture from density functional theory

2017

Density functional theory (DFT) exploits an independent-particle-system construction to replicate the densities and current of an interacting system. This construction is used here to access the exact effective potential and bias of non-equilibrium systems with disorder and interactions. Our results show that interactions smoothen the effective disorder landscape, but do not necessarily increase the current, due to the competition of disorder screening and effective bias. This puts forward DFT as a diagnostic tool to understand disorder screening in a wide class of interacting disordered systems.

Class (set theory)Current (mathematics)Non-equilibrium thermodynamicsFOS: Physical sciences02 engineering and technologyCondensed Matter::Disordered Systems and Neural Networks01 natural sciencesCondensed Matter - Strongly Correlated ElectronsInformationSystems_GENERALdisordered systems0103 physical sciencesMesoscale and Nanoscale Physics (cond-mat.mes-hall)strongly correlated systemsDisorder screeningStatistical physics010306 general physicsdensity functional theoryPhysicsta114Condensed Matter - Mesoscale and Nanoscale PhysicsStrongly Correlated Electrons (cond-mat.str-el)tiheysfunktionaaliteoriaDisordered Systems and Neural Networks (cond-mat.dis-nn)Condensed Matter - Disordered Systems and Neural Networks021001 nanoscience & nanotechnologynonequilibrium Green's functionParticleDensity functional theory0210 nano-technology
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Filtering design for two-dimensional Markovian jump systems with state-delays and deficient mode information

2014

This paper is concerned with the problem of H"~ filtering for a class of two-dimensional Markovian jump linear systems described by the Fornasini-Marchesini local state-space model. The systems under consideration are subject to state-delays and deficient mode information in the Markov chain. The description of deficient mode information is comprehensive that simultaneously includes the exactly known, partially unknown and uncertain transition probabilities. By invoking the properties of the transition probability matrix, together with the convexification of uncertain domains, a new H"~ performance analysis criterion for the filtering error system is firstly derived. Then, via some matrix i…

Class (set theory)Information Systems and ManagementMarkov chainMode (statistics)H filteringComputer Science Applications1707 Computer Vision and Pattern RecognitionState (functional analysis)Filter (signal processing)Deficient mode informationComputer Science ApplicationsTheoretical Computer ScienceSet (abstract data type)Deficient mode information; H filtering; Markovian jump system; State-delay; Two-dimensional system; Artificial Intelligence; Software; Control and Systems Engineering; Theoretical Computer Science; Computer Science Applications1707 Computer Vision and Pattern Recognition; Information Systems and ManagementMatrix (mathematics)Control theoryState-delayArtificial IntelligenceControl and Systems EngineeringMarkovian jump systemApplied mathematicsTwo-dimensional systemDesign methodsSoftwareMathematics
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Integrability of the one dimensional Schrödinger equation

2018

We present a definition of integrability for the one dimensional Schroedinger equation, which encompasses all known integrable systems, i.e. systems for which the spectrum can be explicitly computed. For this, we introduce the class of rigid functions, built as Liouvillian functions, but containing all solutions of rigid differential operators in the sense of Katz, and a notion of natural boundary conditions. We then make a complete classification of rational integrable potentials. Many new integrable cases are found, some of them physically interesting.

Class (set theory)Integrable systemFOS: Physical sciencesComplex analysisAlgebras01 natural sciencesSchrödinger equationsymbols.namesake[MATH.MATH-MP]Mathematics [math]/Mathematical Physics [math-ph]0103 physical sciencesBoundary value problem0101 mathematics010306 general physicsGauge field theoryMathematical PhysicsMathematical physicsMathematicsMSC: 34M46 34M50 37J30Liouville equation010102 general mathematicsSpectrum (functional analysis)Operator theory[ MATH.MATH-MP ] Mathematics [math]/Mathematical Physics [math-ph]Statistical and Nonlinear PhysicsMathematical Physics (math-ph)Differential operatorHamiltonian mechanicssymbols34M46 34M50 37J30
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Model approximation for two-dimensional Markovian jump systems with state-delays and imperfect mode information

2014

Published version of an article in the journal: Multidimensional Systems and Signal Processing. Also available from the publisher at: http://dx.doi.org/10.1007/s11045-013-0276-x This paper is concerned with the problem of {Mathematical expression} model approximation for a class of two-dimensional (2-D) discrete-time Markovian jump linear systems with state-delays and imperfect mode information. The 2-D system is described by the well-known Fornasini-Marchesini local state-space model, and the imperfect mode information in the Markov chain simultaneously involves the exactly known, partially unknown and uncertain transition probabilities. By using the characteristics of the transition proba…

Class (set theory)Mathematical optimizationMarkov chainmodel approximationApplied Mathematicstwo-dimensional systemsMarkovian jump systemsRegular polygonMode (statistics)imperfect mode informationState (functional analysis)VDP::Mathematics and natural science: 400::Mathematics: 410::Analysis: 411Computer Science ApplicationsMarkovian jumpMarkovian jump linear systemsArtificial IntelligenceHardware and ArchitectureSignal ProcessingApplied mathematicsstate-delaysImperfectSoftwareInformation SystemsMathematics
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On Horn spectra

1991

Abstract A Horn spectrum is a spectrum of a Horn sentence. We show that to solve Asser's problem, and consequently the EXPTIME = ? NEXPTIME question it suffices to consider the class of Horn spectra. We also pose the problem whether or not the generator of every Horn spectrum is a spectrum. We prove that from a negative solution of the generator problem, a negative answer for the EXPTIME = ? NEXPTIME question follows. Some other relations between the generator problem and Asser's problem are given. Finally, the relativized version of the generator problem is formulated and it is shown that it has an affirmative solution for some oracles, and a negative solution for some others.

Class (set theory)NEXPTIMEGeneral Computer ScienceFrench hornComputabilitySpectrum (functional analysis)EXPTIMEOracleTheoretical Computer ScienceCombinatoricsComputer Science::Logic in Computer ScienceComputer Science::Formal Languages and Automata TheoryComputer Science(all)Generator (mathematics)MathematicsTheoretical Computer Science
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A Multiplicity result for a class of strongly indefinite asymptotically linear second order systems

2010

We prove a multiplicity result for a class of strongly indefinite nonlinear second order asymptotically linear systems with Dirichlet boundary conditions. The key idea for the proof is to bring together the classical shooting method and the Maslov index of the linear Hamiltonian systems associated to the asymptotic limits of the given nonlinearity.

Class (set theory)Pure mathematicsApplied MathematicsMathematical analysisLinear systemMultiplicity (mathematics)34B15 37J05 53C50Functional Analysis (math.FA)Hamiltonian systemMathematics - Functional AnalysisNonlinear systemsymbols.namesakeShooting methodMathematics - Classical Analysis and ODEsSettore MAT/05 - Analisi MatematicaDirichlet boundary conditionClassical Analysis and ODEs (math.CA)FOS: MathematicssymbolsOrder (group theory)Multiplicity Asymptotically linear BVP Maslov index Phase angleAnalysisMathematics
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Positivity, complex FIOs, and Toeplitz operators

2018

International audience; We establish a characterization of complex linear canonical transformations that are positive with respect to a pair of strictly plurisubharmonic quadratic weights. As an application, we show that the boundedness of a class of Toeplitz operators on the Bargmann space is implied by the boundedness of their Weyl symbols.

Class (set theory)Pure mathematicsFourier integral operator in the complex domainPrimary: 32U05 32W25 35S30 47B35 70H1570H15Mathematics::Classical Analysis and ODEsOcean EngineeringCharacterization (mathematics)32U05 32W25 35S30 47B35 70H15Space (mathematics)01 natural sciencesMathematics - Analysis of PDEsQuadratic equation0103 physical sciencesFOS: Mathematics0101 mathematics[MATH]Mathematics [math]MathematicsMathematics::Functional Analysispositive canonical transformationMathematics::Complex Variables32U0532W25010102 general mathematicsToeplitz matrixFunctional Analysis (math.FA)Mathematics - Functional Analysis35S30Toeplitz operatorpositive Lagrangian plane010307 mathematical physicsstrictly plurisubharmonic quadratic form47B35Analysis of PDEs (math.AP)Toeplitz operator
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A computational and experimental investigation of halloysite silicic surface modifications after alkaline treatment

2023

Density functional theory calculations were performed in order to investigate the formation of silanol groups on the outer surface of halloysite nanotubes, as possible products of the reactions with water in alkaline environments. The results, discussed in terms of energy release and structural properties of the modified surface, suggest that the formation of various kinds of silanol group constellations, and even the extraction of orthosilicic acid, are highly exothermic reaction in the presence of hydroxide ions. Thermogravimetric analysis, FT-IR, XRD and X-ray fluorescence spectrometry performed on halloysite treated at high pH conditions indicate that the adsorption of water on the oute…

Clay materialsGeochemistry and PetrologySpiral nanotubesGeologyFunctionalizationDFTApplied Clay Science
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Comparison of Nonclassic and Classic Phenotype of Hypertrophic Cardiomyopathy Focused on Prognostic Cardiac Magnetic Resonance Parameters: A Single-C…

2022

Patients with nonclassic phenotypes (NCP)—more advanced stages of hypertrophic cardiomyopathy (HCM)—constitute an intriguing and heterogeneous group that is difficult to diagnose, risk-stratify, and treat, and often neglected in research projects. We aimed to compare cardiac magnetic resonance (CMR) parameters in NCP versus classic phenotypes (CP) of HCM with special emphasis given to the parameters of established and potential prognostic importance, including numerous variables not used in everyday clinical practice. The CMR studies of 88 patients performed from 2011 to 2019 were postprocessed according to the study protocol to obtain standard and non-standard parameters. In NCP, the late …

Clinical Biochemistrycardiovascular systemcardiovascular diseasesmagnetic resonance imaging; late gadolinium enhancement; hypertrophic cardiomyopathy; phenotype; sudden cardiac death; new imaging techniques; prognosis; outcomes; functional imaging; left ventricular obstruction; left atrium; mitral valve apparatusDiagnostics
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Novel bifunctional DATA chelator for quick access to site-directed PET 68Ga-radiotracers: preclinical proof-of-principle with [Tyr3]octreotide

2017

Molecular imaging of tumors with the PET radionuclide 68Ga has gained momentum in clinical oncology due to the expanding availability of commercial 68Ge/68Ga-generators in combination with state-of-the-art PET/CT and PET/MRI hybrid imaging systems. Concurrently, interesting peptide-based or small-size vectors have been developed for theranostic use in cancer patients. Owing to the short half-life of 68Ga (t1/2 = 67.7 min) and the sensitivity of many targeting biomolecules, labeling and kit reconstitution in mild conditions allowing for quick access to ready-for-injection PET-tracers are highly desirable. The novel DATA ((6-pentanoic acid)-6-(amino)methy-1,4-diazepinetriacetate) chelator pre…

Clinical OncologyOctreotideNanotechnology010402 general chemistry01 natural sciences030218 nuclear medicine & medical imaging0104 chemical sciencesInorganic Chemistry03 medical and health scienceschemistry.chemical_compound0302 clinical medicinechemistryCancer researchmedicineBifunctional chelatorChelationMolecular imagingBifunctionalClearancemedicine.drugDalton Transactions
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