Search results for "Step"

showing 10 items of 509 documents

On the reactivity of nitrosoimidazoles with acids (the Cusmano–Ruccia reaction): a continuous source of new ring-into-ring interconversion

2014

Abstract An extension of the ‘Cusmano–Ruccia’ reaction is reported. 6-(4-chlorophenyl)-3-methyl-5-nitrosoimidazo[2,1- b ]oxazole by the action of hydrochloric acid gives 3-(4-chlorobenzoyl)-5-methyl-1,2,4-oxadiazole ( 13 ); presumably via ammonium ion, CO 2 and methanol elimination. The relevance of the nature of the atom of the B -ring linked to C-2 of the imidazole for the occurrence of the ring-into-ring interconversion has been once more confirmed.

Multi-step processesOrganic ChemistryHydrochloric acidSettore CHIM/06 - Chimica OrganicaRing (chemistry)BiochemistryMedicinal chemistryIonConsedensed nitrosoimidazoles ring-into-ring interconversion multi-step processes 3-acyl-124-oxadiazoleschemistry.chemical_compoundchemistryCondensed nitrosoimidazoleDrug DiscoveryImidazoleAmmoniumReactivity (chemistry)MethanolRing-into-ring interconversionOxazoleTetrahedron Letters
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Experimental and theoretical evidence for bilayer-by-bilayer surface melting of crystalline ice

2017

On the surface of water ice, a quasi-liquid layer (QLL) has been extensively reported at temperatures below its bulk melting point at 273 K. Approaching the bulk melting temperature from below, the thickness of the QLL is known to increase. To elucidate the precise temperature variation of the QLL, and its nature, we investigate the surface melting of hexagonal ice by combining noncontact, surface-specific vibrational sum frequency generation (SFG) spectroscopy and spectra calculated from molecular dynamics simulations. Using SFG, we probe the outermost water layers of distinct single crystalline ice faces at different temperatures. For the basal face, a stepwise, sudden weakening of the hy…

MultidisciplinarySum-frequency generationMaterials scienceBilayerTransition temperatureSum frequency generationSurface meltingWaterNanotechnology02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnology01 natural sciencesSpectral line0104 chemical sciencesMolecular dynamicsChemical physicsCommentariesMelting pointStepwise0210 nano-technologySpectroscopyCrystalline iceLayer (electronics)Proceedings of the National Academy of Sciences
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Low effective population sizes and limited connectivity inxerothermic beetles: implications for the conservation ofan endangered habita

2014

Fragmentation and isolation may have detrimental effects on the viability of populations. Xerothermic grasslands, which are extra-zonal analogues of steppes, are among Europe's most endangered natural environments. Information about connectivity between the remaining habitat patches is critical for effective conservation planning. However, very little is known about the actual levels of isolation of individual xerothermic patches at the inter-regional and local scale. In this study, 16 microsatellite loci were used to investigate genetic diversity, structuring, effective sizes (Ne), and connectivity among populations of the weevil Centricnemus leucogrammus at various geographic scales. Anal…

Nature reservegeographyGenetic diversityCentricnemus leucogrammusHabitat fragmentationgeography.geographical_feature_categoryEcologySteppeEcologyEndangered speciesPopulation geneticspopulation geneticsBiologysteppedry grasslandsmicrosatellitesCurculionidaeEffective population sizeHabitathabitat fragmentationisolationNature and Landscape ConservationAnimal Conservation
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Parameters analysis of FitzHugh-Nagumo model for a reliable simulation

2014

International audience; Derived from the pioneer ionic Hodgkin-Huxley model and due to its simplicity and richness from a point view of nonlinear dynamics, the FitzHugh-Nagumo model has been one of the most successful neuron / cardiac cell model. It exists many variations of the original FHN model. Though these FHN type models help to enrich the dynamics of the FHN model. The parameters used in these models are often in biased conditions. The related results would be questionable. So, in this study, the aim is to find the parameter thresholds for one of the commonly used FHN model in order to pride a better simulation environment. The results showed at first that inappropriate time step and…

Neurons[ INFO.INFO-TS ] Computer Science [cs]/Signal and Image Processing[INFO.INFO-TS] Computer Science [cs]/Signal and Image ProcessingModels NeurologicalModels CardiovascularAction PotentialsOrder (ring theory)Relaxation (iterative method)[ SPI.SIGNAL ] Engineering Sciences [physics]/Signal and Image processingType (model theory)Time stepCardiac cellNonlinear systemTheoretical physicsLinear relationshipNonlinear Dynamics[INFO.INFO-TS]Computer Science [cs]/Signal and Image ProcessingHumansApplied mathematicsMyocytes CardiacFitzHugh–Nagumo model[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing[SPI.SIGNAL] Engineering Sciences [physics]/Signal and Image processingMathematics2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society
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Non-cooperative game theory based stepwise power tariff model using Monte-Carle simulation for agricultural consumers

2019

Abstract In the present study the concept of non-cooperative game theory is proposed in the retail electricity market for introducing stepwise power tariff model (SPT) for agricultural consumers. The objective of the paper is to increase the energy generation through green energy generation sources (GEGS), introduction of plug-in hybrid electric vehicles, education of families, standard wiring and appliance efficiency in tariffs for agricultural consumers with non-cooperative game theory. Agricultural consumers are able to generate a huge amount of electricity through GEGS and are able to control the consumption in their own way, and the non-cooperative game theory is introduced. Energy con…

Non-cooperative gameretail electricity marketComputer sciencebusiness.industryS020209 energyAgriculture (General)020208 electrical & electronic engineeringTariffAgriculture02 engineering and technologyplug-in hybrid electric vehiclesnon-cooperative game theoryPower (physics)Theory basedS1-972MicroeconomicsAgriculturegreen energy generation sources0202 electrical engineering electronic engineering information engineeringGeneral Agricultural and Biological Sciencesbusinessstepwise power tariff modelOpen Agriculture
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Fuzzy Control Strategy for Cooperative Non-holonomic Motion of Cybercars with Passengers Vibration Analysis

2021

The cybercars are electric road wheeled non-holonomic vehicles with fully automated driving capabilities. They contribute to sustainable mobility and are employed as passenger vehicles. Non-holonomic mechanics describes the motion of the cybercar constrained by non-integrable constraints, i.e. constraints on the system velocities that do not arise from constraints on the configuration alone. First of all there are thus with dynamic nonholonomic constraints, i.e. constraints preserved by the basic Euler-Lagrange equations (Bloch, 2000; Melluso, 2007; Raimondi & Melluso, 2006-a). Of course, these constraints are not externally imposed on the system but rather are consequences of the equations…

Nonholonomic systemComputer scienceHolonomicControl engineeringKalman filterFuzzy control systemKinematicsMotion controlComputer Science::RoboticsCybercars motion control passengers vibration intelligent controlSettore ING-INF/04 - AutomaticaControl theoryBacksteppingTrajectoryCybercars Fuzzy Control Passengers vibration analysis.
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Generalized differential transform method for nonlinear boundary value problem of fractional order

2015

Abstract In this paper the generalized differential transform method is applied to obtain an approximate solution of linear and nonlinear differential equation of fractional order with boundary conditions. Several numerical examples are considered and comparisons with the existing solution techniques are reported. Results show that the method is effective, easier to implement and very accurate when applied for the solution of fractional boundary values problems.

Numerical AnalysisApplied MathematicsMathematical analysisOrder of accuracyFractional derivativeMixed boundary conditionFractional calculusSplit-step methodModeling and SimulationGeneralized differential transformFree boundary problemCauchy boundary conditionBoundary value problemSpectral methodBoundary value problemNonlinear differential equationMathematicsCommunications in Nonlinear Science and Numerical Simulation
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Step-by-step integration for fractional operators

2018

Abstract In this paper, an approach based on the definition of the Riemann–Liouville fractional operators is proposed in order to provide a different discretisation technique as alternative to the Grunwald–Letnikov operators. The proposed Riemann–Liouville discretisation consists of performing step-by-step integration based upon the discretisation of the function f(t). It has been shown that, as f(t) is discretised as stepwise or piecewise function, the Riemann–Liouville fractional integral and derivative are governing by operators very similar to the Grunwald–Letnikov operators. In order to show the accuracy and capabilities of the proposed Riemann–Liouville discretisation technique and th…

Numerical AnalysisDiscretizationApplied Mathematics02 engineering and technologyFunction (mathematics)DerivativeWhite noise01 natural sciences010305 fluids & plasmasExponential functionFractional calculus020303 mechanical engineering & transports0203 mechanical engineeringModeling and SimulationStep function0103 physical sciencesPiecewiseApplied mathematicsFractional Calculus Riemman–Liouville Grünwald–Letnikov Discrete fractional operatorsMathematics
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Hermite interpolation: The barycentric approach

1991

The barycentric formulas for polynomial and rational Hermite interpolation are derived; an efficient algorithm for the computation of these interpolants is developed. Some new interpolation principles based on rational interpolation are discussed.

Numerical AnalysisMathematical analysisComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISIONMathematicsofComputing_NUMERICALANALYSISTrilinear interpolationStairstep interpolationBirkhoff interpolationComputer Science ApplicationsTheoretical Computer SciencePolynomial interpolationComputational MathematicsComputational Theory and MathematicsNearest-neighbor interpolationHermite interpolationComputingMethodologies_SYMBOLICANDALGEBRAICMANIPULATIONApplied mathematicsSpline interpolationSoftwareComputingMethodologies_COMPUTERGRAPHICSMathematicsInterpolationComputing
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Reconstructions that combine interpolation with least squares fitting

2015

We develop a reconstruction that combines interpolation and least squares fitting for point values in the context of multiresolution a la Harten. We study the smoothness properties of the reconstruction as well as its approximation order. We analyze how different adaptive techniques (ENO, SR and WENO) can be used within this reconstruction. We present some numerical examples where we compare the results obtained with the classical interpolation and the interpolation combined with least-squares approximation. We develop a reconstruction that combines interpolation and least squares fitting.We study the smoothness properties of the reconstruction and its approximation order.We present some nu…

Numerical AnalysisMathematical optimizationApplied MathematicsTrilinear interpolationBilinear interpolationStairstep interpolationLinear interpolationMultivariate interpolationComputational MathematicsNearest-neighbor interpolationApplied mathematicsSpline interpolationMathematicsInterpolationApplied Numerical Mathematics
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