Search results for "online"

showing 10 items of 4526 documents

Construction sequence analysis of long-span cable-stayed bridges

2018

Abstract In cantilever construction of long-span cable-stayed bridges the stressing sequence of stays is fundamental for establishing the final configuration of the bridge. The structural behaviour of these bridges is usually evaluated through a forward staged construction analysis, in which the values of the prestressing forces to be applied to stays are the main unknowns. A unified procedure for determining the initial cable forces and for analyzing the entire sequence is presented here, considering the geometric nonlinearity of stays through the Dischinger equivalent elastic modulus. The target is the simultaneous determination of the initial cable forces with the simulation of the const…

CantileverComputer science0211 other engineering and technologiesNAPS020101 civil engineering02 engineering and technologyBridge (nautical)0201 civil engineeringDeckStress (mechanics)Effects of uncertainties021105 building & constructionPylonForward analysisCivil and Structural EngineeringSequenceConstruction sequencebusiness.industryProbabilistic logicProbabilistic approachCable-stayed structures; Construction sequence; Effects of uncertainties; Forward analysis; NAPS; Partial scheme; PES; Probabilistic approach; Civil and Structural EngineeringStructural engineeringPESSettore ICAR/09 - Tecnica Delle CostruzioniNonlinear systemPartial schemebusinessCable-stayed structures
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Diffusion processes with ultrametric jumps

2007

Abstract In the theory of spin glasses the relaxation processes are modelled by random jumps in ultrametric spaces. One may argue that at the border of glassy and nonglassy phases the processes combining diffusion and jumps may be relevant. Using the Dirichlet form technique we construct a model of diffusion on the real line with jumps on the Cantor set. The jumps preserve the ultrametric feature of a random process on unit ball of 2-adic numbers.

Cantor setUnit sphereDirichlet formStochastic processMathematical analysisStatistical and Nonlinear PhysicsRelaxation (approximation)Diffusion (business)Condensed Matter::Disordered Systems and Neural NetworksReal lineUltrametric spaceMathematical PhysicsMathematicsReports on Mathematical Physics
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Microbubble PhoXonic resonators: Chaos transition and transfer

2022

We report the activation of optomechanical chaotic oscillations in microbubble resonators (MBRs) through a blue-side excitation of its optical resonances. We confirm the sequence of quasi-periodical oscillation, spectral continuum and aperiodic motion; as well as the transition to chaos without external feedback or modulation of the laser source. In particular, quasi periodic transitions and a spectral continuum are reported for MBRs with diameters up to 600 μm, whereas only an abrupt transition into a spectral con- tinuum is observed for larger microbubbles.

Caos (Teoria de sistemes)General MathematicsApplied MathematicsGeneral Physics and AstronomyStatistical and Nonlinear PhysicsÒptica
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PHASE EQUILIBRIA IN THIN POLYMER FILMS

2001

Within self-consistent field theory and Monte Carlo simulations the phase behavior of a symmetrical binary AB polymer blend confined into a thin film is studied. The film surfaces interact with the monomers via short ranged potentials. One surface attracts the A component and the corresponding semi-infinite system exhibits a first order wetting transition. The surface interaction of the opposite surface is varied as to study the crossover from capillary condensation for symmetric surface fields to interface localization/delocalization transition for antisymmetric surface fields. In the former case the phase diagram has a single critical point close to the bulk critical point. In the latter…

Capillary waveMaterials scienceWetting transitionMean field theoryCondensed matter physicsCritical point (thermodynamics)Triple pointPhase (matter)Statistical and Nonlinear PhysicsIsing modelCondensed Matter PhysicsPhase diagramInternational Journal of Modern Physics B
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Absolute and relative quantification of RNA modifications via biosynthetic isotopomers

2014

In the resurging field of RNA modifications, quantification is a bottleneck blocking many exciting avenues. With currently over 150 known nucleoside alterations, detection and quantification methods must encompass multiple modifications for a comprehensive profile. LC-MS/MS approaches offer a perspective for comprehensive parallel quantification of all the various modifications found in total RNA of a given organism. By feeding (13)C-glucose as sole carbon source, we have generated a stable isotope-labeled internal standard (SIL-IS) for bacterial RNA, which facilitates relative comparison of all modifications. While conventional SIL-IS approaches require the chemical synthesis of single mod…

Carbon IsotopesTandem Mass SpectrometryEscherichia coli500 Natural sciences and mathematicsMethods OnlineRNANucleosides500 NaturwissenschaftenReference Standards13PseudouridineChromatography LiquidNucleic Acids Research
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An integrated approach based on uniform quantization for the evaluation of complexity of short-term heart period variability: Application to 24 h Hol…

2007

We propose an integrated approach based on uniform quantization over a small number of levels for the evaluation and characterization of complexity of a process. This approach integrates information-domain analysis based on entropy rate, local nonlinear prediction, and pattern classification based on symbolic analysis. Normalized and non-normalized indexes quantifying complexity over short data sequences (∼300 samples) are derived. This approach provides a rule for deciding the optimal length of the patterns that may be worth considering and some suggestions about possible strategies to group patterns into a smaller number of families. The approach is applied to 24 h Holter recordings of …

Cardiac outputDaytimeCardiac Output LowGeneral Physics and AstronomyRisk AssessmentSensitivity and SpecificityPhysics and Astronomy (all)Heart RateReference ValuesRisk FactorsOscillometryStatisticsHeart ratemedicineMathematical PhysicHumansCircadian rhythmDiagnosis Computer-AssistedMathematical PhysicsEntropy rateMathematicsmedicine.diagnostic_testApplied MathematicsReproducibility of ResultsStatistical and Nonlinear PhysicsSignal Processing Computer-AssistedIntegrated approachmedicine.diseasePrognosisSystems IntegrationHeart failureElectrocardiography AmbulatoryAlgorithmElectrocardiographyAlgorithmsStatistical and Nonlinear PhysicChaos (Woodbury, N.Y.)
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Evaluation of Hemodynamic Parameters for Adaptive Control of the Artificial Heart by Simulation of the Vascular System

1984

Abstract A nonlinear dynamic mathematical model of the cardiovascular system is outlined, which is employable to analyse the hemodynamic system behaviour under normal as well as under pathological conditions. By modifying this model, assuming that cardiac output is constant at a preset level (which is in accordance with most of the total artificial heart systems, since their pumps output is preselected with fixed driving parameters), the hemodynamic behaviour of a circulation system with an artificial heart was simulated. Comparing the simulation results with those obtained from total artificial heart experiments, a good agreement in right atrial and aortic pressure under exercise condition…

Cardiac outputEngineeringAdaptive controlbusiness.industryHemodynamicsOptimal controllaw.inventionSystem modelNonlinear systemlawArtificial heartAortic pressurebusinessSimulationIFAC Proceedings Volumes
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Application of the star-product method to the angular momentum quantization

1992

We define a *-product on ℝ3 and solve the polarization equation f*C=0 where C is the Casimir of the coadjoint representation of SO(3). We compute the action of SO(3) on the space of solutions. We then examine the case of non-zero eigenvalues of C, in order to find finite-dimensional representations of SO(3). Finally, we compute \(\sqrt C *\sqrt C \) as an asymptotic series of C. This gives an explanation of the use of the star square root of C in a paper by Bayen et al. instead of its natural square root.

Casimir effectAngular momentumQuantization (physics)Coadjoint representationSquare rootStar productStatistical and Nonlinear PhysicsGeometryAsymptotic expansionMathematical PhysicsEigenvalues and eigenvectorsMathematicsMathematical physicsLetters in Mathematical Physics
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INTEGRAL SOLUTIONS TO A CLASS OF NONLOCAL EVOLUTION EQUATIONS

2010

We study the existence of integral solutions to a class of nonlinear evolution equations of the form [Formula: see text] where A : D(A) ⊆ X → 2X is an m-accretive operator on a Banach space X, and f : [0, T] × X → X and [Formula: see text] are given functions. We obtain sufficient conditions for this problem to have a unique integral solution.

Cauchy problemClass (set theory)Pure mathematicsApplied MathematicsGeneral MathematicsOperator (physics)Mathematical analysisBanach spaceIntegral solutionFixed pointNonlinear evolutionFourier integral operatorMathematicsCommunications in Contemporary Mathematics
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On Approximation of Entropy Solutions for One System of Nonlinear Hyperbolic Conservation Laws with Impulse Source Terms

2010

We study one class of nonlinear fluid dynamic models with impulse source terms. The model consists of a system of two hyperbolic conservation laws: a nonlinear conservation law for the goods density and a linear evolution equation for the processing rate. We consider the case when influx-rates in the second equation take the form of impulse functions. Using the vanishing viscosity method and the so-called principle of fictitious controls, we show that entropy solutions to the original Cauchy problem can be approximated by optimal solutions of special optimization problems.

Cauchy problemConservation lawOptimization problemEntropy solutionsArticle SubjectVanishing viscosity methodMathematical analysisNonlinear fluid dynamicmodelsNonlinear conservation lawlcsh:QA75.5-76.95Computer Science ApplicationsNonlinear systemlcsh:TA1-2040Modeling and SimulationEvolution equationNonlinear fluid dynamicmodels; Vanishing viscosity method; Principle of fictitious controls; Entropy solutionsPrinciple of fictitious controlslcsh:Electronic computers. Computer scienceElectrical and Electronic Engineeringlcsh:Engineering (General). Civil engineering (General)Hyperbolic partial differential equationEntropy (arrow of time)MathematicsJournal of Control Science and Engineering
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