Search results for "Numerical results"

showing 4 items of 4 documents

The Windy clustered prize-collecting arc-routing problem

2011

This paper introduces the windy clustered prize-collecting arc-routing problem. It is an arc-routing problem where each demand edge is associated with a profit that is collected once if the edge is serviced, independent of the number of times the edge is traversed. It is further required that if a demand edge is serviced, then all the demand edges of its component are also serviced. A mathematical programming formulation is given and some polyhedral results including several facet-defining and valid inequalities are presented. The separation problem for the different families of inequalities is studied. Numerical results from computational experiments are analyzed. © 2011 INFORMS.

Arc routingMathematical optimizationMathematical programmingTransportation68W AlgorithmsSeparation problemsCutting plane algorithmsArc routing problems:Informàtica::Informàtica teòrica [Àrees temàtiques de la UPC]Prize-collectingPolyhedral modellingNumerical resultsProfitability indexProfitabilityPolyhedral analysisComputational experimentMATEMATICA APLICADAArc routingCutting plane algorithmValid inequalityAlgorithmsCivil and Structural EngineeringSeparation problemMathematicsMathematicsofComputing_DISCRETEMATHEMATICS
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Undergraduate experiment with fractal diffraction gratings

2011

We present a simple diffraction experiment with fractal gratings based on the triadic Cantor set. Diffraction by fractals is proposed as a motivating strategy for students of optics in the potential applications of optical processing. Fraunhofer diffraction patterns are obtained using standard equipment present in most undergraduate physics laboratories and compared with those obtained with conventional periodic gratings. It is shown that fractal gratings produce self-similar diffraction patterns which can be evaluated analytically. Good agreement is obtained between experimental and numerical results. © 2011 IOP Publishing Ltd.

DiffractionPhysics::OpticsGeneral Physics and Astronomysymbols.namesakeOpticsFractalSelf-similarDiffraction gratingPhysicsOptical processingScience instructionUndergraduate experimentPotential applicationsbusiness.industryPeriodic gratingsDiffraction patternsCantor setsOptical processingFraunhofer diffractionCantor setInterferometryPhysics laboratoriesFractalsInterferometryStandard equipmentsFISICA APLICADAsymbolsNumerical resultsDiffraction gratingsFraunhofer diffraction patternsbusinessExperiments
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Numerical and experimental study of liquid metal stirring by rotating permanent magnets

2018

In this work, we study liquid gallium stirring by rotating permanent magnets. We demonstrate possibility of easily creating different flow patterns by rotating permanent magnets, which can be industrially important for controlling heat and mass transfer processes in the system. Unlike the typical approach of simulating magnet rotation as a transient problem and time-averaging the Lorentz forces, we solve the magnet rotation as a harmonic (frequency domain) problem, which leads to forces equal to time-averaged ones and decreases the simulation time considerably. Numerical results are validated using qualitative flow structure results from the neutron radiography visualization of tracer parti…

Liquid metalMaterials sciencePermanent magnetsNumerical modelsUltrasonic Doppler velocimeters02 engineering and technologyQuantitative dataRotationHeat and mass transfer process020501 mining & metallurgyPhysics::Fluid DynamicsMagnetohydrodynamicssymbols.namesakeFrequency domainsneutron radiographyLiquid metal stirringTransient problemsFrequency domain analysisddc:530Mass transferUDVMagnetic materialsMetal meltingNumerical and experimental studyData visualizationnumerical modellingMechanicsVelocimetry0205 materials engineeringFrequency domainMagnetNumerical resultsHarmonicsymbolsUltrasound Doppler velocimetryDewey Decimal Classification::500 | Naturwissenschaften::530 | PhysikTransient (oscillation)Lorentz forceLiquid metalsIOP Conference Series: Materials Science and Engineering
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Mutual inductance for an explicitly finite number of turns

2011

Published version of an article published in Progress In Electromagnetics Research B, 28, 273-287. Also available from the publisher at http://www.jpier.org/pierb/pier.php?paper=10110103 Non coaxial mutual inductance calculations, based on a Bessel function formulation, are presented for coils modelled by an explicitly finite number of circular turns. The mutual inductance of two such turns can be expressed as an integral of a product of three Bessel functions and an exponential factor, and it is shown that the exponential factors can be analytically summed as a simple geometric progression, or other related sums. This allows the mutual inductance of two thin solenoids to be expressed as an…

analytical expressions exponential factors finite number geometric progressions mutual inductance numerical results representative case thin solenoids bessel functions electric windings solenoids inductanceVDP::Technology: 500::Electrotechnical disciplines: 540
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