Search results for " functions"

showing 10 items of 972 documents

Skaitļu teorija: lekcijas, lasītas Latvijas Universitātes Matemātikas un dabas zinātņu fakultātē

1936

Lekcijas sakārtojis Fogels, Ernests ; rediģējis Lūsis, Arvīds.

Algebraic number theoryNumber theoryAritmētiskās funkcijas:MATHEMATICS::Applied mathematics::Numerical analysis [Research Subject Categories]Arithmetic functionsNumbers rationalMatemātikaKongruenti skaitļiAlgebriskā skaitļu teorijaSkaitļu teorijaSkaitļi racionālie
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An improved algorithm for thermal dynamic simulation of walls using Z-transform coefficients

2003

The Transfer Function Method (TFM), recommended by American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), is one of the most modern tools available to solve heat transfer problems in building envelopes and environments. TFM utilises Z-transform to solve the equations system that describes the heat transfer in a multi-layered wall. Due to an analogy with an electric circuit, it is possible to write the equations system in a matrix suitable to be solved by computer. Authors carried out an analysis on an historical building placed in the south of Italy to test the reliability and the quality of the thermal dynamic simulation using TFM. The analysis is performed usi…

AlgorithmProblem solvingSettore ING-IND/11 - Fisica Tecnica AmbientaleMathematical operatorTransfer functionsBuildingMathematical transformationComputer simulationMatrix algebra
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Gabor systems and almost periodic functions

2017

Abstract Inspired by results of Kim and Ron, given a Gabor frame in L 2 ( R ) , we determine a non-countable generalized frame for the non-separable space AP 2 ( R ) of the Besicovic almost periodic functions. Gabor type frames for suitable separable subspaces of AP 2 ( R ) are constructed. We show furthermore that Bessel-type estimates hold for the AP norm with respect to a countable Gabor system using suitable almost periodic norms of sequences.

Almost periodic functionApplied Mathematics010102 general mathematicsAlmost-periodic functions010103 numerical & computational mathematicsGabor frame01 natural sciencesLinear subspaceFunctional Analysis (math.FA)Separable spaceCombinatoricsMathematics - Functional AnalysisFramesNorm (mathematics)42C40 42C15 42A75FOS: MathematicsAP-framesCountable set0101 mathematicsGabor systemsMathematicsAlmost-periodic functions; AP-frames; Frames; Gabor systems; Applied Mathematics
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Data from: Functional responses of multi-taxa communities to disturbance and stress gradients in a restored floodplain

2015

1. Trait-based approaches can reveal the mechanisms through which disturbances or stress impact communities, allowing comparisons of the role of different mechanisms in shaping communities among taxonomic groups. Such information can lead to higher comparability, transferability and predictability of the outcome of restoration projects. However, multitaxa trait-based approaches were rarely used in the context of ecosystem restoration. 2. We investigated the responses to environmental gradients of seven taxa (vascular plants, staphylinid and carabid beetles, spiders, isopods, diplopods and earthworms) in a restored floodplain using a species traits approach. We assessed the impact of flood d…

Annelidacommunity weighted mean of traitsLife SciencesearthwormsStaphylinidaeriparian ecosystemsmedicine and health carespecies traitsDiplopodaAraneaecosystem functionsMedicineCarabidaePlantaeArthropodsIsopoda
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Indefinite integrals of products of special functions

2016

ABSTRACTA method is given for deriving indefinite integrals involving squares and other products of functions which are solutions of second-order linear differential equations. Several variations of the method are presented, which applies directly to functions which obey homogeneous differential equations. However, functions which obey inhomogeneous equations can be incorporated into the products and examples are given of integrals involving products of Bessel functions combined with Lommel, Anger and Weber functions. Many new integrals are derived for a selection of special functions, including Bessel functions, associated Legendre functions, and elliptic integrals. A number of integrals o…

Applied Mathematics010102 general mathematicsMathematical analysisTrigonometric integral010103 numerical & computational mathematicsParabolic cylinder functionGeneralized hypergeometric function01 natural sciencesAddition theoremJacobi elliptic functionsOrder of integration (calculus)Special functionsSlater integrals0101 mathematicsAnalysisMathematicsIntegral Transforms and Special Functions
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Norm or numerical radius attaining polynomials on C(K)

2004

Abstract Let C(K, C ) be the Banach space of all complex-valued continuous functions on a compact Hausdorff space K. We study when the following statement holds: every norm attaining n-homogeneous complex polynomial on C(K, C ) attains its norm at extreme points. We prove that this property is true whenever K is a compact Hausdorff space of dimension less than or equal to one. In the case of a compact metric space a characterization is obtained. As a consequence we show that, for a scattered compact Hausdorff space K, every continuous n-homogeneous complex polynomial on C(K, C ) can be approximated by norm attaining ones at extreme points and also that the set of all extreme points of the u…

Applied MathematicsMathematical analysisBanach spaceHausdorff spaceContinuous functions on a compact Hausdorff spaceCombinatoricsMetric spacesymbols.namesakeUniform normNorm (mathematics)Hausdorff dimensionsymbolsStone–Weierstrass theoremAnalysisMathematicsJournal of Mathematical Analysis and Applications
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A geometrical criterion for nonexistence of constant-sign solutions for some third-order two-point boundary value problems

2020

We give a simple geometrical criterion for the nonexistence of constant-sign solutions for a certain type of third-order two-point boundary value problem in terms of the behavior of nonlinearity in the equation. We also provide examples to illustrate the applicability of our results.

Applied MathematicsMathematical analysislcsh:QA299.6-433lcsh:AnalysisType (model theory)nonexistence of solutionsthird-order two-point boundary value problemsNonlinear systemThird orderSimple (abstract algebra)comparison methods for the first zero functionsBoundary value problemConstant (mathematics)Value (mathematics)AnalysisMathematicsSign (mathematics)Nonlinear Analysis
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L’évolution récente des expositions temporaires sur le Moyen Âge en Italie: Public, thèmes, finalités

2011

This article proposes a reflection about Italian art exhibitions on Middle Ages all over the twentieth century in order to understand the reception of medieval history in Italy. The Italian case is compared with the other European countries and their own relationships with Middle Ages. The articles studies also the important changes in the cultural offer and in the museum function during the last decade of the twentieth century and analyses their major consequences on the exhibitions. Lastly the ‘status’ of the exhibited objects and their mise-en-scene are examined.

ArcheologyHistoryHistoryVisual Arts and Performing ArtsAnthropologystatus of the exhibited objectArt history[SHS.ART]Humanities and Social Sciences/Art and art historyExhibitionMedieval historyMise en scènemise-en-scènecultural offerMiddle Agesreception of medieval historylcsh:NX440-632Exhibitions of medieval artmuseum functionslcsh:History of the artsComputingMilieux_MISCELLANEOUSZograf
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In-medium jet shape from energy collimation in parton showers: Comparison with CMS PbPb data at 2.76 TeV

2014

Abstract: We present the medium-modified energy collimation in the leading-logarithmic approximation (LLA) and next-to-leading-logarithmic approximation (NLLA) of QCD. As a consequence of more accurate kinematic considerations in the argument of the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) fragmentation functions (FFs) we find a new NLLA correction O ð α s Þ which accounts for the scaling violation of DGLAP FFs at small x . The jet shape is derived from the energy collimation within the same approximations and we also compare our calculations for the energy collimation with the event generators PYTHIA 6 and Y A JEM for the first time in this paper. The modification of jets by the …

Astrophysics::High Energy Astrophysical Phenomenacolor coherencefragmentation functionsHigh Energy Physics::Experimenthadron spectracollisions
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Intercomparison and analyses of the climatology of the West African Monsoon in the West African Monsoon Modeling and Evaluation project (WAMME) first…

2010

International audience; This paper briefly presents the West African Monsoon (WAM) Modeling and Evaluation Project (WAMME) and evaluates WAMME general circulation models' (GCM) performances in simulating variability of WAM precipitation, surface temperature, and major circulation features at seasonal and intraseasonal scales in the first WAMME experiment. The analyses indicate that models with specified sea surface temperature generally have reasonable simulations of the pattern of spatial distribution of WAM seasonal mean precipitation and surface temperature as well as the averaged zonal wind in latitude-height cross-section and low level circulation. But there are large differences among mo…

Atmospheric Science010504 meteorology & atmospheric sciences[SDE.MCG]Environmental Sciences/Global Changes0207 environmental engineeringTropical Easterly JetEmpirical orthogonal functions02 engineering and technologySensible heatOceanographyMonsoon01 natural sciencesMeteorology/ClimatologyLatent heatGeophysics/GeodesyPrecipitation020701 environmental engineering0105 earth and related environmental sciencesAfrican easterly jet[ SDE.MCG ] Environmental Sciences/Global ChangesSea surface temperature[SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology13. Climate actionClimatologyEarth SciencesEnvironmental science[ SDU.STU.CL ] Sciences of the Universe [physics]/Earth Sciences/ClimatologyClimate Dynamics
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