Search results for " proof"

showing 10 items of 118 documents

Multiplicity results for Sturm-Liouville boundary value problems

2009

Multiplicity results for Sturm-Liouville boundary value problems are obtained. Proofs are based on variational methods.

Partial differential equationSturm-Liouville problem variational methodsApplied MathematicsNumerical analysisMultiplicity resultsMathematical analysisSturm–Liouville theoryMixed boundary conditionMathematics::Spectral TheoryMathematical proofCritical point (mathematics)Computational MathematicsSettore MAT/05 - Analisi MatematicaBoundary value problemMathematics
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Ultrasonic cavity solitons

2007

We report on a new type of localized structure, an ultrasonic cavity soliton, supported by large aspect-ratio acoustic resonators containing viscous media. These states of the acoustic and thermal fields are robust structures, existing whenever a spatially uniform solution and a periodic pattern coexist. Direct proof of their existence is given both through the numerical integration of the model and through the analysis and numerical integration of a generalized Swift-Hohenberg equation, derived from the microscopic equations under conditions close to nascent bistability. An analytical solution for the ultrasonic cavity soliton is given.

PhysicsBistabilityGeneral Physics and AstronomyFOS: Physical sciencesPattern Formation and Solitons (nlin.PS)Type (model theory)Nonlinear Sciences - Pattern Formation and SolitonsNumerical integrationResonatorClassical mechanicsThermalUltrasonic sensorDirect proofSoliton
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Waveguides. Radiation Principle. Scattering Matrices

2021

Chapter 2 exposes a mathematical model of a waveguide with several cylindrical ends going to infinity, basic notions and mathematical results (with complete proofs) needed in successive chapters: waves, continuous spectrum eigenfunctions, intrinsic radiation principle, and scattering matrices.

Physicsbusiness.industryScatteringmedia_common.quotation_subjectContinuous spectrumEigenfunctionRadiationMathematical proofInfinitylaw.inventionClassical mechanicsOpticslawbusinessWaveguidemedia_common
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Thermal deformations of inhomogeneous elastic plates

1995

We consider thermal deformations of transversally inhomogenous elastic plates. Thin plate equations are derived as limits of full three-dimensional models both in the linear was well as in the non-linear case with appropriate convergence proofs. In the non-linear case also the corresponding von Karman equations are formulated. Its is obtained that the inhomogeneity leads to the loss of some symmetry properties at the von Karman equations

Physics::Fluid DynamicsClassical mechanicsVon karman equationsGeneral MathematicsThermalConvergence (routing)General EngineeringNon linear modelConvergence proofsFöppl–von Kármán equationsSymmetry (physics)Three dimensional modelMathematicsMathematical Methods in the Applied Sciences
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On Using the Theory of Regular Functions to Prove the ε-Optimality of the Continuous Pursuit Learning Automaton

2013

Published version of a chapter in the book: Recent Trends in Applied Artificial Intelligence. Also available from the publisher at: http://dx.doi.org/10.1007/978-3-642-38577-3_27 There are various families of Learning Automata (LA) such as Fixed Structure, Variable Structure, Discretized etc. Informally, if the environment is stationary, their ε-optimality is defined as their ability to converge to the optimal action with an arbitrarily large probability, if the learning parameter is sufficiently small/large. Of these LA families, Estimator Algorithms (EAs) are certainly the fastest, and within this family, the set of Pursuit algorithms have been considered to be the pioneering schemes. The…

Property (philosophy)Learning automataComputer scienceVDP::Mathematics and natural science: 400::Information and communication science: 420::Algorithms and computability theory: 422Structure (category theory)Monotonic functionMathematical proofAutomatonArbitrarily largeε-optimalityContinuous Pursuit AlgorithmCalculuspursuit algorithmsAlgorithmVariable (mathematics)
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Quantum Security Proofs Using Semi-classical Oracles

2019

We present an improved version of the one-way to hiding (O2H) Theorem by Unruh, J ACM 2015. Our new O2H Theorem gives higher flexibility (arbitrary joint distributions of oracles and inputs, multiple reprogrammed points) as well as tighter bounds (removing square-root factors, taking parallelism into account). The improved O2H Theorem makes use of a new variant of quantum oracles, semi-classical oracles, where queries are partially measured. The new O2H Theorem allows us to get better security bounds in several public-key encryption schemes.

Provable securityFlexibility (engineering)Post-quantum cryptographyTheoretical computer scienceComputer sciencebusiness.industry0102 computer and information sciences02 engineering and technologyMathematical proofEncryption01 natural sciencesPublic-key cryptographyUnruh effect010201 computation theory & mathematics0202 electrical engineering electronic engineering information engineeringParallelism (grammar)020201 artificial intelligence & image processingbusiness
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On a question of C. Bonnafé on characters and multiplicity free constituents

2019

Abstract In 2006, C. Bonnafe posed a general question on characters of finite groups. A positive answer would have reduced drastically some proofs by G. Lusztig.

Pure mathematicsAlgebra and Number TheoryMultiplicity (mathematics)Mathematics::Representation TheoryMathematical proofMathematicsJournal of Algebra
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Strong Converse Results for Linking Operators and Convex Functions

2020

We consider a family B n , ρ c of operators which is a link between classical Baskakov operators (for ρ = ∞ ) and their genuine Durrmeyer type modification (for ρ = 1 ). First, we prove that for fixed n , c and a fixed convex function f , B n , ρ c f is decreasing with respect to ρ . We give two proofs, using various probabilistic considerations. Then, we combine this property with some existing direct and strong converse results for classical operators, in order to get such results for the operators B n , ρ c applied to convex functions.

Pure mathematicsArticle Subject010102 general mathematicsMathematicsofComputing_GENERALProbabilistic logicType (model theory)Mathematical proof01 natural sciences010104 statistics & probabilityTheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGESBaskakov operatorConverseQA1-939Order (group theory)0101 mathematicsConvex functionLink (knot theory)AnalysisMathematicsMathematicsJournal of Function Spaces
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Global fixed point proof of time-dependent density-functional theory

2011

We reformulate and generalize the uniqueness and existence proofs of time-dependent density-functional theory. The central idea is to restate the fundamental one-to-one correspondence between densities and potentials as a global fixed point question for potentials on a given time-interval. We show that the unique fixed point, i.e. the unique potential generating a given density, is reached as the limiting point of an iterative procedure. The one-to-one correspondence between densities and potentials is a straightforward result provided that the response function of the divergence of the internal forces is bounded. The existence, i.e. the v-representability of a density, can be proven as wel…

Pure mathematicsCondensed Matter - Materials ScienceQuantum PhysicsAtomic Physics (physics.atom-ph)Materials Science (cond-mat.mtrl-sci)FOS: Physical sciencesGeneral Physics and AstronomyExistence theorem02 engineering and technologyFunction (mathematics)Fixed point021001 nanoscience & nanotechnologyMathematical proof01 natural sciencesUpper and lower boundsPhysics - Atomic PhysicsUniqueness theorem for Poisson's equationBounded function0103 physical sciencesUniquenessQuantum Physics (quant-ph)010306 general physics0210 nano-technologyMathematics
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A new proof of the support theorem and the range characterization for the Radon transform

1983

The aim of this note is to give a new and elementary proof of the support theorem for the Radon transform, which is based only on the projection theorem and the Paley-Wiener theorem for the Fourier transform. The idea is to solve a certain system of linear equations in order to determine the coefficients of a homogeneous polynomial (interpolation problem). By the same method, we get a short proof of the range characterization for Radon transforms of functions supported in a ball.

Pure mathematicsFactor theoremRadon transformGeneral MathematicsProjection-slice theoremMathematical analysisElementary proofFourier inversion theoremBrouwer fixed-point theoremRadon's theoremShift theoremMathematicsManuscripta Mathematica
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