Search results for "Transform"

showing 10 items of 3975 documents

Generalizations of Clausen's formula and algebraic transformations of Calabi-Yau differential equations

2011

AbstractWe provide certain unusual generalizations of Clausen's and Orr's theorems for solutions of fourth-order and fifth-order generalized hypergeometric equations. As an application, we present several examples of algebraic transformations of Calabi–Yau differential equations.

AlgebraPure mathematicsAlgebraic transformationsMonodromyDifferential equationGeneral MathematicsCalabi–Yau manifoldDifferential algebraic geometryGeneralized hypergeometric functionDifferential algebraic equationHypergeometric distributionMathematics
researchProduct

Kollineationen und Schliessungssätze für Ebene Faserungen

1979

Every affine central collineation of a translation plane π induces a special collineation of the projective space π spanned by the spreadF belonging to π. Here the relations between these special collineations of π and certain incidence propositions inF are investigated; so new proofs are given for some characterisations of (A,B)-regular spreads included in [7].

AlgebraPure mathematicsCollineationTranslation planeProjective spaceGeometry and TopologyAffine transformationMathematical proofIncidence (geometry)MathematicsJournal of Geometry
researchProduct

Elliptic convolution operators on non-quasianalytic classes

2001

For those nonquasianalytic classes in which an extension of the classical Borel's theorem holds we show that every elliptic convolution operator is the composition of a translation and an invertible ultradifferential operator. This answers a question asked by Chou in: La transformation de Fourier complexe et l'equation de convolution, LNM 325, Berlin-Heidelberg-New York (1973).

AlgebraSemi-elliptic operatorsymbols.namesakeOperator (computer programming)Fourier transformGeneral MathematicssymbolsConvolution theoremConvolution powerShift operatorCircular convolutionConvolutionMathematicsArchiv der Mathematik
researchProduct

LORENTZ SPACES OF VECTOR-VALUED MEASURES

2003

Algebrasymbols.namesakeGeneral MathematicsLorentz transformationMathematical analysissymbolsMathematicsJournal of the London Mathematical Society
researchProduct

Geometry of the projectivization of ideals and applications to problems of birationality

2018

In this thesis, we interpret geometrically the torsion of the symmetric algebra of the ideal sheaf I_Z of a scheme Z defined by n+1 equations in an n-dimensional variety. This is equivalent to study the geometry of the projectivization of I_Z. The applications of this point of view concern, in particular, the topic of birational maps of the projective space of dimension 3 for which we construct explicit birational maps that have the same algebraic degree as their inverse, free and nearly-free curves for which we generalise a characterization of free curves by extending the notion of Milnor and Tjurina numbers. We tackle also the topic of homaloidal hypersurfaces, our original motivation, fo…

Algebraic geometrySyzygiesBirational mapsTransformations birationellesHypersurfaces homaloïdesGéométrie algébriqueHomaloidal hypersurfaces[MATH.MATH-AG] Mathematics [math]/Algebraic Geometry [math.AG][MATH.MATH-AG]Mathematics [math]/Algebraic Geometry [math.AG]Commutative algebraSingularitiesSingularitésAlgèbre commutative
researchProduct

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
researchProduct

Ammonium ion mediated resorcarene capsules: ESI-FTICRMS study on gas-phase structure and ammonium ion affinity of tetraethyl resorcarene and its per-…

2003

AbstractThe ammonium ion binding affinities of tetraethyl resorcarene (1) and its per-methylated derivative (2) were studied by electrospray ionization Fourier transform ion cyclotron resonance (ESI-FTICR) mass spectrometry. Ten different ammonium ions were tested as guests for the resorcarenes. A strong tendency for complex formation was observed with all ammonium ions of size and charge distribution suitable for noncovalent interactions with the cavities of the resorcarene hosts 1 and 2. Although differences in ammonium ion affinities were observed between 1 and 2 due to the dissimilar conformations, the overall tendency was that increase in the degree of substitution and the length of ca…

Ammonium bromideChemistryStereochemistryElectrospray ionizationIon cyclotron resonance spectrometryMass spectrometryFourier transform ion cyclotron resonanceInclusion compoundchemistry.chemical_compoundStructural BiologyPolymer chemistryAmmoniumAmmonium ion bindingSpectroscopyJournal of the American Society for Mass Spectrometry
researchProduct

<title>Stereovision studies by disbalanced images</title>

2003

Studies are focused on design and appraisal of an objective test of the quality of stereovision depending on optical stimuli blurring and detecting of the stereovision threshold at various stimuli blur degree. The method is based on the principles of grayscale and color random dot stereotests. Experiments may be divided with respect to the principle of demonstration: 1) the blur is modeled by defocusing an optical lens - the strength of the optical system is varied at a constant quality of the stimulus, or 2) the blur is simulated on the computer screen - here the quality of the stimulus varies. To obtain an independent description and to measure blurring the experimentally demonstrated ima…

Amplitude modulationsymbols.namesakeFourier transformbusiness.industryStereotestssymbolsComputer visionArtificial intelligencebusinessGrayscaleComputing systemsMathematicsSPIE Proceedings
researchProduct

Field desorption mass spectrometric characterization of thiol conjugates related to the oxidative metabolism of the anticancer drug 4′-(9-acridinylam…

1983

Conjugation products with glutathione (GSH) and other endogenous thiol derivatives related to the oxidative metabolism of the anticancer drug, 4′-(9-acridinlyamino) methanesulfon-m-anisidide (m-AMSA) were synthesized and characterized by field desorption mass spectrometry. The primary microsomal oxidation product of m-AMSA, m-AQDI, was prepared by MnO2 oxidation of the parent drug and reacted with equimolar GSH, cysteine, N-acetylcysteine and N-acetylcysteine methyl ester to form m-AMSA-(5′)-thiol conjugates linkedat the aniline ring, as major products. Field desorption mass spectra of the conjugates provided abundant [MH]plus; ions, and characteristic fragment ions by cleavage at the thioe…

AmsacrineAminoacridinesStereochemistryGlutathioneMedicinal chemistryMass SpectrometryRatsAdductchemistry.chemical_compoundAnilineLiverchemistryThioetherThiolysisAcridineAnimalsMoietyCysteamineSulfhydryl CompoundsBiotransformationSpectroscopyCysteineBiological Mass Spectrometry
researchProduct

Decoding vibrational states of Concanavalin A amyloid fibrils.

2015

International audience; Amyloid and amyloid-like fibrils are a general class of protein aggregates and represent a central topic in life sciences for their involvement in several neurodegenerative disorders and their unique mechanical and supramolecular morphological properties. Both their biological role and their physical properties, including their high mechanical stability and thermodynamic inertia, are related to the structural arrangement of proteins in the aggregates at molecular level. Significant variations may exist in the supramolecular organization of the commonly termed cross-β structure that constitutes the amyloid core. In this context, a fine knowledge of the structural deta…

AmyloidAbsorption spectroscopy[SDV]Life Sciences [q-bio]BiophysicsSupramolecular chemistry02 engineering and technologymacromolecular substancesProtein aggregationAntiparallel (biochemistry)FibrilSpectrum Analysis RamanBiochemistryVibrationProtein Structure Secondary03 medical and health sciencessymbols.namesakeSpectroscopy Fourier Transform InfraredConcanavalin AHumansFourier transform infrared spectroscopyRaman030304 developmental biology0303 health sciencesChemistryOrganic ChemistryIntermolecular force021001 nanoscience & nanotechnologyAmyloid FTIR RAMAN hydration water THz spectroscopy[SDV] Life Sciences [q-bio]CrystallographyFTIRTerahertz spectroscopysymbolsBiophysicsFibrils0210 nano-technologyRaman spectroscopy
researchProduct