Search results for "STAR"

showing 10 items of 4285 documents

Notas sobre el problema social

1949

DiosDemocraciaPublicaciones: Obra periodística: Columnas y artículos de opiniónProblema socialRELIGIÓNHambreVidal-Beneyto JoséSOCIEDADVida dignaPOLÍTICAMalestar social
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Stark level crossing and optical-rf double resonance in NaK D 1 Π

1997

We report here (Lambda) -doubling splitting and permanent electric dipole moment d p measurements for a number of vibrotational levels of NaK D 1 II state. Two different methods, which are not Doppler limited, were used. Stark effect induced level crossing was registered as fluorescence polarization changes with external electric field, which allowed us to obtain, from one fit, the values of electric dipole moment and (Lambda) -doubling splitting (Delta) ef between e, f substates of an individual rotational state. Another method consisted in obtaining the ratio (Delta) ef /d p from electric field dependence of the intensity of forbidden line appeared in fluorescence as a result of e- f Star…

DipolePolarization densitysymbols.namesakeElectric dipole momentStark effectChemistryExcited stateElectric fieldTransition dipole momentsymbolsAtomic physicsMagnetic dipoleSPIE Proceedings
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Longest Motifs with a Functionally Equivalent Central Block

2004

International audience; This paper presents a generalization of the notion of longest repeats with a block of k don't care symbols introduced by [Crochemore et al., LATIN 2004] (for k fixed) to longest motifs composed of three parts: a first and last that parameterize match (that is, match via some symbol renaming, initially unknown), and a functionally equivalent central block. Such three-part motifs are called longest block motifs. Different types of functional equivalence, and thus of matching criteria for the central block are considered, which include as a subcase the one treated in [Crochemore et al., LATIN 2004] and extend to the case of regular expressions with no Kleene closure or …

Discrete mathematics0303 health sciences[INFO.INFO-DS]Computer Science [cs]/Data Structures and Algorithms [cs.DS]Block (permutation group theory)0102 computer and information sciences01 natural sciencesCombinatoricsKleene algebra03 medical and health sciencesClosure (mathematics)010201 computation theory & mathematicsAlgorithmicsKleene starRegular expressionTime complexity030304 developmental biologyMathematicsComplement (set theory)
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On the Shuffle of Star-Free Languages

2012

Motivated by the general problem to characterize families of languages closed under shuffle, we investigate some conditions under which the shuffle of two star-free languages is star-free. Some of the special cases here approached give rise to new problems in combinatorics on words.

Discrete mathematicsAlgebra and Number TheorySettore INF/01 - Informaticapure submonoidGeneral problemAbstract family of languagesRegular languageComputer Science::Computation and Language (Computational Linguistics and Natural Language and Speech Processing)Star (graph theory)star-free languageCone (formal languages)shuffle of languagePumping lemma for regular languagesTheoretical Computer ScienceCombinatorics on wordsComputational Theory and MathematicsRegular languagecombinatorics on words.Information SystemsMathematicsFundamenta Informaticae
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ON THE STAR HEIGHT OF RATIONAL LANGUAGES

1994

Two problems concerning the star height of a rational language are investigated: the star height one problem and the relationships between the unambiguity of an expression and its star height. For this purpose we consider the class of factorial, transitive and rational (FTR) languages. From the algebraic point of view a FTR language is the set of factors of a rational submonoid M. Two subclasses of FTR languages are introduced: renewal languages, corresponding to the case of M finitely generated, and unambiguous renewal languages, corresponding to the case of M finitely generated and free. We prove that a FTR language has star height one if and only if it is renewal. This gives a simple de…

Discrete mathematicsFactorialTransitive relationStar heightGeneral Mathematicsmedia_common.quotation_subjectComputer Science::Computation and Language (Computational Linguistics and Natural Language and Speech Processing)AmbiguityRegular languageIf and only ifComputer Science::Programming LanguagesEntropy (information theory)Algebraic numberMathematicsmedia_commonInternational Journal of Algebra and Computation
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A Mönch type fixed point theorem under the interior condition

2009

Abstract In this paper we show that the well-known Monch fixed point theorem for non-self mappings remains valid if we replace the Leray–Schauder boundary condition by the interior condition. As a consequence, we obtain a partial generalization of Petryshyn's result for nonexpansive mappings.

Discrete mathematicsMathematics::Functional AnalysisGeneralizationApplied MathematicsInterior conditionMathematics::Analysis of PDEsBanach spaceFixed-point theoremType (model theory)Mönch fixed point theoremBanach spacesStrictly star-shaped setLeray–Schauder conditionBoundary value problemAnalysisMathematicsJournal of Mathematical Analysis and Applications
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Fixed point properties and proximinality in Banach spaces

2009

Abstract In this paper we prove the existence of a fixed point for several classes of mappings (mappings admitting a center, nonexpansive mappings, asymptotically nonexpansive mappings) defined on the closed convex subsets of a Banach space satisfying some proximinality conditions. In particular, we derive a sufficient condition, more general than weak star compactness, such that if C is a bounded closed convex subset of l 1 satisfying this condition, then every nonexpansive mapping T : C → C has a fixed point.

Discrete mathematicsMathematics::Functional AnalysisPure mathematicsApplied MathematicsRegular polygonBanach spaceCenter (group theory)Star (graph theory)Fixed pointCompact spaceBounded functionCoincidence pointAnalysisMathematicsNonlinear Analysis: Theory, Methods & Applications
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The Star Height One Problem for Irreducible Automata

1993

The star height of a regular expression is, informally, the maximum number of nested stars in the expression. The star height of a regular language is the minimal star height of a regular expression denoting this language. The notion of star height indicates in a certain sense the “loop complexity” of a regular expression and thus it gives a measure of the complexity of a regular language.

Discrete mathematicsStar heightAstrophysics::Cosmology and Extragalactic AstrophysicsExpression (computer science)Measure (mathematics)AutomatonLoop (topology)StarsRegular languageAstrophysics::Solar and Stellar AstrophysicsAstrophysics::Earth and Planetary AstrophysicsRegular expressionArithmeticAstrophysics::Galaxy AstrophysicsMathematics
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Relatively Orthocomplemented Skew Nearlattices in Rickart Rings

2015

AbstractA class of (right) Rickart rings, called strong, is isolated. In particular, every Rickart *-ring is strong. It is shown in the paper that every strong Rickart ring R admits a binary operation which turns R into a right normal band having an upper bound property with respect to its natural order ≤; such bands are known as right normal skew nearlattices. The poset (R, ≤) is relatively orthocomplemented; in particular, every initial segment in it is orthomodular.The order ≤ is actually a version of the so called right-star order. The one-sided star orders are well-investigated for matrices and recently have been generalized to bounded linear Hilbert space operators and to abstract Ric…

Discrete mathematicsrestrictive semigroupskew nearlatticelcsh:MathematicsGeneral MathematicsMathematics::Rings and AlgebrasSkewlcsh:QA1-939right normal bandright-star orderrelatively orthocomplemented posetOrthogonalityorthogonalityRickart ringMathematicsDemonstratio Mathematica
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Validation of a New Method for the Diagnosis of Rotor bar Failures via Wavelet Transformation in Industrial Induction Machines

2006

[EN] In this paper, the authors propose a method for the diagnosis of rotor bar failures in induction machines, based on the analysis of the stator current during the startup using the discrete wavelet transform (DWT). Unlike other approaches, the study of the high-order wavelet signals resulting from the decomposition is the core of the proposed method. After an introduction of the physical and mathematical bases of the method, a description of the proposed approach is given; for this purpose, a numerical model of induction machine is used in such a way that the effects of a bar breakage can clearly be shown, avoiding the influence of other phenomena not related with the fault. Afterward, …

Discrete wavelet transformEngineeringStatorCascade algorithmWavelet analysisFault (power engineering)Industrial and Manufacturing Engineeringlaw.inventionHarmonic analysisBroken rotor barssymbols.namesakeWaveletControl theorylawElectrical and Electronic EngineeringFault diagnosisbusiness.industryRotor (electric)Wavelet transformTime–frequency analysisFourier transformControl and Systems Engineeringsymbolsstartup transientINGENIERIA ELECTRICAbusinessInduction motor
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