Search results for "Compres"

showing 10 items of 1107 documents

Asymptotic preserving IMEX finite volume schemes for low Mach number Euler equations with gravitation

2017

In this paper we will present and analyze a new class of the IMEX finite volume schemes for the Euler equations with a gravity source term. We will in particular concentrate on a singular limit of weakly compressible flows when the Mach number M1. In order to efficiently resolve slow dynamics we split the whole nonlinear system in a stiff linear part governing the acoustic and gravity waves and a non-stiff nonlinear part that models nonlinear advection effects. For time discretization we use a special class of the so-called globally stiffly accurate IMEX schemes and approximate the stiff linear operator implicitly and the non-stiff nonlinear operator explicitly. For spatial discretization t…

Numerical AnalysisFinite volume methodPhysics and Astronomy (miscellaneous)DiscretizationApplied MathematicsMathematical analysis010103 numerical & computational mathematics01 natural sciencesComputer Science ApplicationsEuler equations010101 applied mathematicsLinear mapComputational Mathematicssymbols.namesakeNonlinear systemMach numberModeling and SimulationStability theorysymbolsCompressibility0101 mathematicsMathematicsJournal of Computational Physics
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Comparison between adaptive and uniform discontinuous Galerkin simulations in dry 2D bubble experiments

2013

Accepted by the Journal of Computational Physics Adaptive mesh refinement generally aims to increase computational efficiency without compromising the accuracy of the numerical solution. However it is an open question in which regions the spatial resolution can actually be coarsened without affecting the accuracy of the result. This question is investigated for a specific example of dry atmospheric convection, namely the simulation of warm air bubbles. For this purpose a novel numerical model is developed that is tailored towards this specific application. The compressible Euler equations are solved with a Discontinuous Galerkin method. Time integration is done with an IMEXmethod and the dy…

Numerical AnalysisMathematical optimizationPhysics and Astronomy (miscellaneous)Mathematical modelAdaptive mesh refinementApplied MathematicsNumerical analysisAdaptive Mesh RefinementCompressible flowComputer Science ApplicationsEuler equationsDry Warm Air BubbleComputational Mathematicssymbols.namesakeMeteorologyIMEXDiscontinuous Galerkin methodModeling and SimulationDiscontinuous GalerkinsymbolsApplied mathematicsGalerkin methodNavier–Stokes equationsMathematicsJournal of Computational Physics
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Weighted ENO interpolation and applications

2004

Abstract Data-dependent interpolatory techniques such as essentially non-oscillatory (ENO) technique [J. Comput. Phys. 71 (1987) 231] have long been used as a reconstruction process in multiresolution schemes. In this work we analyze the weighted ENO (WENO) technique introduced by Liu et al. in the context of conservation laws [J. Comput. Phys. 115 (1994) 200] and improved by Jiang and Shu [J. Comput. Phys. 126 (1996) 202], and apply it to the compression of images, using multiresolution techniques.

Numerical AnalysisMultiscale decompositionConservation lawDiscretizationApplied MathematicsModeling and SimulationCompression (functional analysis)Mathematical analysisApplied mathematicsContext (language use)Mathematics::Numerical AnalysisInterpolationMathematicsCommunications in Nonlinear Science and Numerical Simulation
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Editor's Choice – European Society for Vascular Surgery (ESVS) 2021 Clinical Practice Guidelines on the Management of Venous Thrombosis

2021

European Society for Vascular Surgery (ESVS) 2021 Clinical Practice Guidelines on the Management of Venous Thrombosis

ORAL ANTICOAGULANT-THERAPYmedicine.medical_specialtyELASTIC COMPRESSION STOCKINGSMEDLINEED AMERICAN-COLLEGEInferior vena cavaCATHETER-DIRECTED THROMBOLYSISBlood vessel prosthesisdeep-vein-thrombosisHeparin-induced thrombocytopeniamedicineYoung adultUPPER EXTREMITY DEEPbusiness.industryINFERIOR VENA-CAVAHEPARIN-INDUCED-THROMBOCYTOPENIAsilent pulmonary-embolismMOLECULAR-WEIGHT HEPARINVascular surgerymedicine.diseaseSurgeryClinical PracticeVenous thrombosismedicine.veinSurgeryCardiology and Cardiovascular MedicinebusinessEuropean Journal of Vascular and Endovascular Surgery
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Seawater carbonate chemistry and percentage cover of macroalgal species at three locations at Vulcano, Italy

2017

Beneficial effects of CO2 on photosynthetic organisms will be a key driver of ecosystem change under ocean acidification. Predicting the responses of macroalgal species to ocean acidification is complex, but we demonstrate that the response of assemblages to elevated CO2 are correlated with inorganic carbon physiology. We assessed abundance patterns and a proxy for CO2:HCO3- use (delta 13C values) of macroalgae along a gradient of CO2 at a volcanic seep, and examined how shifts in species abundance at other Mediterranean seeps are related to macroalgal inorganic carbon physiology. Five macroalgal species capable of using both HCO3- and CO2 had greater CO2 use as concentrations increased. Th…

Ocean Acidification International Coordination Centre (OA-ICC)TemperateRegistration number of speciesSalinityCaulerpa proliferaCommunity composition and diversityBicarbonate ion standard deviationUdotea petiolatainorganicAlkalinity total standard deviationAlkalinitySargassum muticumDictyota dichotomaHalopteris scopariaYearsCystoseira brachycarpaExperimentTemperature waterCarbon inorganic dissolvedCystoseira foeniculaceaCaulerpa racemosaCalculated using seacarb after Nisumaa et al 2010Cystoseira foeniculataAragonite saturation stateAlkalinity totaltotalCO2 ventpHTemperaturedissolvedCarbonate ionPartial pressure of carbon dioxide (water) at sea surface temperature (wet air)Acetabularia acetabulumJania rubensCarbon dioxide standard deviationEarth System Researchδ13CLipid contentstandard deviationField observationUniform resource locator link to referenceCystoseira crinitaCoverageCalcite saturation stateLocationwaterSiteRocky-shore communityFigureBenthosUniform resource locator/link to referenceOcean Acidification International Coordination Centre OA ICCMediterranean SeaCarbon inorganic dissolved standard deviationTypeBicarbonate ionDictyopteris polypodioidesDilophus fasciolaCalculated using seacarb after Nisumaa et al. (2010)SpeciesCystoseira compressaEvent labelCarbonate system computation flagpH standard deviationCarbonate ion standard deviationMassFugacity of carbon dioxide (water) at sea surface temperature (wet air)CarbonOxygenPartial pressure of carbon dioxide water at sea surface temperature wet airCarbon dioxideRocky shore communityEntire communityFugacity of carbon dioxide water at sea surface temperature wet airPadina pavonicaSeasonδ13C standard deviationCoast and continental shelfCodium bursaTableCystoseira barbarta
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Macroalgal responses to ocean acidification depend on nutrient and light levels

2015

Ocean acidification may benefit algae that are able to capitalize on increased carbon availability for photosynthesis, but it is expected to have adverse effects on calcified algae through dissolution. Shifts in dominance between primary producers will have knock-on effects on marine ecosystems and will likely vary regionally, depending on factors such as irradiance (light vs. shade) and nutrient levels (oligotrophic vs. eutrophic). Thus experiments are needed to evaluate interactive effects of combined stressors in the field. In this study, we investigated the physiological responses of macroalgae near a CO2 seep in oligotrophic waters off Vulcano (Italy). The algae were incubated in situ …

Ocean Acidification International Coordination Centre (OA-ICC)TemperateSalinityChlorophyll aFucoxanthininorganicAlkalinityPhotosynthetic efficiency standard errorChlorophyll cNitrogen content per dry mass standard errorLight saturation point standard errorPhenolics allTemperature waterCarbon inorganic dissolvedMacroalgaeCalculated using seacarb after Nisumaa et al 2010Carbon Nitrogen ratioAragonite saturation stateAlkalinity totalallCarbon per dry massSalinity standard errortotalCarbon content per dry mass standard errorPhenolics all standard errorCO2 ventChromistapHMaximum photochemical quantum yield of photosystem II standard errorTemperaturePartial pressure of carbon dioxide (water) at sea surface temperature (wet air) standard errordissolvedAntioxidant activity standard errorCarbonate ionMaximum photochemical quantum yield of photosystem IIPartial pressure of carbon dioxide (water) at sea surface temperature (wet air)Field experimentstandard errorNitrogen content per dry massElectron transport rate standard errorFucoxanthin standard errorEarth System ResearchViolaxanthinPhenolicsChlorophyll a standard errorCarbon dioxide standard errorPotentiometric titrationCalcite saturation stateCarbon/Nitrogen ratio standard errorNitrogenOchrophytaPotentiometricper dry masswaterChlorophyll c standard errorBenthosAlkalinity total standard errorAntioxidant activityElectron transport rateLight saturation pointOcean Acidification International Coordination Centre OA ICCMacro-nutrientsMediterranean SeaNitrogen per dry massBicarbonate ionTemperature water standard errorCalculated using seacarb after Nisumaa et al. (2010)Primary production PhotosynthesisSpeciespH standard errorCalcite saturation state standard errorCystoseira compressaCalculated using CO2SYSNon photochemical quenchingCarbon content per dry massCarbonate system computation flagViolaxanthin standard errorPrimary production/PhotosynthesisFugacity of carbon dioxide (water) at sea surface temperature (wet air)CarbonCarbon/Nitrogen ratioBiomass/Abundance/Elemental compositionTreatmentPartial pressure of carbon dioxide water at sea surface temperature wet airAragonite saturation state standard errorCarbon dioxideMacro nutrientsCarbonate ion standard errorSingle speciesFugacity of carbon dioxide water at sea surface temperature wet airPadina pavonicaBiomass Abundance Elemental compositionCoast and continental shelfPhotosynthetic efficiencyBicarbonate ion standard errorNon photochemical quenching standard error
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Self-phase modulation-based 2R regenerator including pulse compression and offset filtering for 42.6 Gbit/s RZ-33% transmission systems

2009

International audience; We report on the experimental and theoretical study of a self-phase-modulation-based regenerator at 42.6 Gbit/s with a return-to-zero 33% format. We point out some detrimental effects such as intrachannel interactions and Brillouin scattering. An efficient solution, relying on a self-phase-modulation-based pulse compressor in combination with the regenerator, is proposed to overcome these detrimental phenomena. The experimental demonstration shows the effectiveness of a wavelength-transparent regenerator at 42.6 Gbit/s with a sensitivity-improvement of more than 5 dB and an eye-opening improvement of 2.3 dB in a back-to-back configuration, as well as a 10 times maxim…

Offset (computer science)Materials science060.2330 ; 070.4340 ; 190.3270 ; 190.438002 engineering and technologyMamyshev 2R regeneratorSensitivity and Specificity01 natural sciences010309 optics020210 optoelectronics & photonicsOpticsBrillouin scattering0103 physical sciences0202 electrical engineering electronic engineering information engineeringComputer SimulationMicrowavesSelf-phase modulationOptical amplifierbusiness.industryCross-phase modulationOptical DevicesReproducibility of ResultsEquipment DesignModels TheoreticalAtomic and Molecular Physics and OpticsEquipment Failure AnalysisRefractometryPulse compressionRegenerative heat exchangerTelecommunicationsComputer-Aided DesignbusinessFiltration
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The role of bisphosphonates in the treatment of painful metastatic bone disease: a review of phase III trials.

1998

Metastatic bone disease is a frequent cause of morbidity in advanced cancer patients with a subsequent high incidence of skeletal complications (fractures, hypercalcemia, spinal cord compression) and severe pain. The osteolytic process is mainly characterized by an osteoclastic activity of bone resorption and inflammatory activity provoked by various cytokines and prostaglandins. Bisphosphonates represent a new class of drugs with inhibitory activity on bone resorption and on inflammatory processes which revealed themselves to be efficacious in a series of clinical conditions such as tumour-induced hypercalcemia, Paget's disease, osteoporosis and metastatic bone disease. The aim of this rev…

OncologyQuality of lifemedicine.medical_specialtyBone diseaseOsteoporosisBone NeoplasmsBone resorptionMetastasisBreast cancerSpinal cord compressionInternal medicinemedicineBisphosphonateHumansCancer painMultiple myelomaPalliative therapyDiphosphonatesbusiness.industryPalliative Caremedicine.diseaseSurgeryBone metastaseAnesthesiology and Pain MedicineNeurologyClinical Trials Phase III as TopicNeurology (clinical)Randomized trialbusinessCancer painPainReferences
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Semantics driven interaction using natural language in students tutoring

2007

The aim of this work is to introduce a semantic integration between an ontology and a chatbot in an Intelligent Tutoring Systems (ITS) to interact with students using natural language. The interaction process is driven by the use of a purposely defined ontology. In the ontology two types of conceptual relations are defined. Besides the usual relations, which are used to define the domain's structure, another type of relation is used to define the navigation schema inside the ontology according to the need of managing uncertainty. Uncertainty level is related to student knowledge level about the involved concepts. In this work we propose an ITS for the Java programming language called TutorJ…

Ontology Inference LayerComputer sciencecomputer.internet_protocolOntology (information science)Semanticscomputer.software_genreOWL-SIntelligent tutoring systemsLatent semantic analysisNatural language dialogueSemantic driven interactionSemantic navigationSemantic similaritySemantic computingSchema (psychology)Upper ontologySemantic integrationSemantic compressionSettore ING-INF/05 - Sistemi Di Elaborazione Delle Informazionisemantic navigationLatent semantic analysisbusiness.industryOntology-based data integrationKnowledge levelIntelligent Tutoring SystemsOntologylatent semantic analysisArtificial intelligencesemantic driven interactionbusinesscomputernatural language dialogueNatural language processing
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Update endokrine Orbitopathie

2009

Ophthalmologymedicine.medical_specialtymedicine.diagnostic_testDecompressionPractice patternsbusiness.industrymedicineMEDLINECombined Modality TherapyRadiologybusinessThyroid function testsSurgical methodsKlinische Monatsblätter für Augenheilkunde
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