Search results for "Function"

showing 10 items of 14432 documents

Development of Slewing Mirror Telescope Optical System for the UFFO-pathfinder

2013

The Slewing Mirror Telescope (SMT) is the UV/optical telescope of UFFO-pathfinder. The SMT optical system is a Ritchey-Chretien (RC) telescope of 100 mm diameter pointed by means of a gimbal-mounted flat mirror in front of the telescope. The RC telescope has a 17 × 17arcmin2 in Field of View and 4.3 arcsec resolution (full width half maximum of the point spread function) The beam-steering mirror enables the SMT to access a 35 × 35degree region and point and settle within 1 sec. All mirrors were fabricated to about 0.02 wavelengths RMS in wave front error (WFE) and 84.7% average reflectivity over 200 nm ~ 650 nm. The RC telescope was aligned to 0.05 wavelengths RMS in WFE (test wavelength 63…

WavefrontPoint spread functionPhysicsbusiness.industryGeneral EngineeringAstronomy and AstrophysicsField of viewAstrophysicsOptical telescopelaw.inventionTelescopeWavelengthFull width at half maximumOpticsPathfinderSpace and Planetary Sciencelawbusiness
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Tolerance to rotation of toric monofocal and bifocal intraocular lenses. A theoretical study

2018

Abstract This manuscript aims to evaluate the tolerance to rotation of a toric monofocal and a toric bifocal intraocular lenses with different cylinder powers. Theoretical designs based on wavefront aberrations were created to simulate a toric monofocal and a toric bifocal intraocular lens. Cylinder power ranged from −1 D to −6 D, in steps of −1 D. Tolerance to rotation was estimated by the visual Strehl ratio based on the optical transfer function (VSOTF) metric. Tolerance to rotation for both monofocal and bifocal intraocular lenses decreased when the cylinder power increased. For the bifocal design studied, the tolerance to rotation was larger for the near focus than for the far, however…

Wavefrontbusiness.industrymedicine.medical_treatmentStrehl ratioIntraocular lensRotation01 natural sciencesAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic Materials010309 optics03 medical and health sciences0302 clinical medicineOpticsIntraocular lensesOptical transfer function0103 physical sciences030221 ophthalmology & optometrymedicineCylinderElectrical and Electronic EngineeringFocus (optics)businessMathematicsOptik
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Structure of longitudinal chromomagnetic fields in high energy collisions

2014

We compute expectation values of spatial Wilson loops in the forward light cone of high-energy collisions. We consider ensembles of gauge field configurations generated from a classical Gaussian effective action as well as solutions of high-energy renormalization group evolution with fixed and running coupling. The initial fields correspond to a color field condensate exhibiting domain-like structure over distance scales of order the saturation scale. At later times universal scaling emerges at large distances for all ensembles, with a nontrivial critical exponent. Finally, we compare the results for the Wilson loop to the two-point correlator of magnetic fields.

We compute expectation values of spatial Wilson loops in the forward light cone of high-energy collisions. We consider ensembles of gauge field configurations generated from a classical Gaussian effective action as well as solutions of high-energy renormalization group evolution with fixed and running coupling. The initial like structure over distance scales of oder the saturation scale. At later times universal scaling emerges at large distances for all ensembles with a nontrivial critical exponent. Finally we compare the resulats for the Wilson loop to the two-point correlator of magnetic fields. (C) 2014 The Authors. Published by Elsevier BV This is an open access article under the CC BY licenseNuclear and High Energy PhysicsWilson loopLARGE NUCLEINuclear TheoryField (physics)FOS: Physical sciences114 Physical sciences01 natural sciencesColor-glass condensateRENORMALIZATION-GROUPNuclear Theory (nucl-th)GLUON DISTRIBUTION-FUNCTIONSHigh Energy Physics - Phenomenology (hep-ph)Light cone0103 physical sciencesSCATTERINGGauge theory010306 general physicsSMALL-XEffective actionPhysicsCORRELATORSta114010308 nuclear & particles physicsCOLOR GLASS CONDENSATERenormalization groupEVOLUTIONJIMWLK EQUATIONHigh Energy Physics - PhenomenologySATURATIONQuantum electrodynamicsCritical exponentPhysics Letters B
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Convergence of inertial prox-penalization and inertial forward-backward algorithms for solving bilevel monotone equilibrium problems

2023

The main focus of this paper is on bilevel optimization on Hilbert spaces involving two monotone equilibrium bifunctions. We present a new achievement consisting on the introduction of inertial methods for solving this type of problems. Indeed, two several inertial type methods are suggested: a proximal algorithm and a forwardbackward one. Under suitable conditions and without any restrictive assumption on the trajectories, the weak and strong convergence of the sequence generated by the both iterative methods are established. Two particular cases illustrating the proposed methods are thereafter discussed with respect to hierarchical minimization problems and equilibrium problems under a sa…

Weak and strong convergenceBilevel Equilibrium problemsEquilibrium Fitzpatrick transformProximal algorithm[MATH] Mathematics [math]Monotone bifunctions
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Weak and strong convergence of an inertial proximal method for solving bilevel monotone equilibrium problems

2022

In this paper, we introduce an inertial proximal method for solving a bilevel problem involving two monotone equilibrium bifunctions in Hilbert spaces. Under suitable conditions and without any restrictive assumption on the trajectories, the weak and strong convergence of the sequence generated by the iterative method are established. Two particular cases illustrating the proposed method are thereafter discussed with respect to hierarchical minimization problems and equilibrium problems under saddle point constraint. Furthermore, a numerical example is given to demonstrate the implementability of our algorithm. The algorithm and its convergence results improve and develop previous results i…

Weak and strong convergenceBilevel Equilibrium problemsOptimization and Control (math.OC)G.1.6Equilibrium Fitzpatrick transformFOS: MathematicsProximal algorithm90C33 49J40 46N10 65K15 65K10[MATH.MATH-OC] Mathematics [math]/Optimization and Control [math.OC]Monotone bifunctionsMathematics - Optimization and Control
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Informing, engaging, mobilizing or interacting: Searching for a European model of web campaigning

2011

This study presents data from content analyses of the websites of all parties that stood in the 2009 European parliamentary elections in France, Germany, Great Britain and Poland. It cross-nationally examines the main functions of the websites, the adoption of Web 1.0 and Web 2.0 features, and the political and cultural factors that determine parties’ online communication. The findings show that while the main website function varies across countries, Web 1.0 is still the dominant mode of campaigning. Moreover, offline inequalities within and between nations determine differences in parties’ individual online strategies: specifically, major parties in states with long histories of democrac…

Web 2.0business.industryCommunicationmedia_common.quotation_subjectPolitical communicationPublic relationsLanguage and LinguisticsDemocracyPoliticsPolitical scienceGeneral electionNormalization (sociology)The InternetbusinessFunction (engineering)media_commonEuropean Journal of Communication
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Gaussian quadrature rule for arbitrary weight function and interval

2005

Abstract A program for calculating abscissas and weights of Gaussian quadrature rules for arbitrary weight functions and intervals is reported. The program is written in Mathematica. The only requirement is that the moments of the weight function can be evaluated analytically in Mathematica. The result is a FORTRAN subroutine ready to be utilized for quadrature. Program summary Title of program: AWGQ Catalogue identifier:ADVB Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADVB Program obtained from: CPC Program Library, Queens University, Belfast, N. Ireland Computer for which the program is designed and others on which it has been tested: Computers: Pentium IV 1.7 GHz processor Ins…

Weight functionComputer scienceFortranMathematicsofComputing_NUMERICALANALYSISGeneral Physics and AstronomyGauss–Kronrod quadrature formulaTanh-sinh quadratureQuadrature (mathematics)symbols.namesakeHardware and ArchitecturesymbolsGaussian quadratureAlgorithmcomputerClenshaw–Curtis quadratureTest datacomputer.programming_languageComputer Physics Communications
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COMPARISON OF EXPERIMENTS WITH WEIGHTED DISTRIBUTIONS

1989

In this paper the standard statistical experiment in which a random sample is drawn from some distribution involving an unknown parameter θ is compared with experiments in which samples are obtained from different weighted versions of that distribution, so that the underlying probability of entering the sample is multiplied by some weight function. This comparison is carried out by means of the concepts of sufficiency and pairwise sufficiency as developed in Blackwell's theory of the comparison of statistical experiments. Many examples are presented which illustrate the wide variety of effects that weight functions can have on the information about θ.

Weight functionDistribution (mathematics)StatisticsPairwise comparisonSample (statistics)Variety (universal algebra)Mathematics
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Expected principal stress directions under multiaxial random loading. Part I: theoretical aspects of the weight function method

1999

As has been observed experimentally by many authors, the position of the fatigue fracture plane appears to strongly depend on the directions of the principal stresses or strains. In Part I of the present work the expected principal stress directions under multiaxial random loading are theoretically obtained by averaging the instantaneous values of the three Euler angles through some suitable weight functions which are assumed to take into account the main factors influencing fatigue behaviour. Then, in Part II, it is examined how such theoretical principal directions determined by applying the proposed procedure are correlated to the position of the experimental fracture plane for some fati…

Weight functionMaterials scienceContinuum mechanicsbusiness.industryMechanical EngineeringMathematical analysisPrincipal (computer security)Work (physics)Fracture mechanicsStructural engineeringStrength of materialsIndustrial and Manufacturing EngineeringEuler anglessymbols.namesakeMechanics of MaterialsPosition (vector)Modeling and SimulationsymbolsGeneral Materials SciencebusinessInternational Journal of Fatigue
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Fatigue fracture planes and expected principal stress directions under biaxial variable amplitude loading

2005

Fatigue behaviour under multiaxial variable amplitude loading can be examined by applying the failure criteria based on the critical plane approach. Positions of the critical plane can be determined in relation to the principal stress or strain directions. In the present paper, the expected directions of the principal stresses under proportional and non-proportional loading have been obtained by averaging the instantaneous values of the Euler angles through special weight functions. The known weight functions based on stress parameters appear not to be efficient for each loading or material being analysed. Thus, the authors consider new weight functions based on energy parameters. The prese…

Weight functionMaterials sciencebusiness.industryMechanical EngineeringMathematical analysisBiaxial tensile testTorsion (mechanics)Structural engineeringFracture planeEuler anglessymbols.namesakeAmplitudeMechanics of MaterialssymbolsPrincipal stressGeneral Materials SciencebusinessPlane stressFatigue <html_ent glyph="@amp;" ascii="&"/> Fracture of Engineering Materials and Structures
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