Search results for "Crete"

showing 10 items of 2495 documents

Common Fixed Points in a Partially Ordered Partial Metric Space

2013

In the first part of this paper, we prove some generalized versions of the result of Matthews in (Matthews, 1994) using different types of conditions in partially ordered partial metric spaces for dominated self-mappings or in partial metric spaces for self-mappings. In the second part, using our results, we deduce a characterization of partial metric 0-completeness in terms of fixed point theory. This result extends the Subrahmanyam characterization of metric completeness.

Discrete mathematicsArticle SubjectInjective metric spacelcsh:MathematicsEquivalence of metricslcsh:QA1-939Fixed points dominated self-mappings 0-completenessConvex metric spaceIntrinsic metricCombinatoricsMetric spaceSettore MAT/05 - Analisi MatematicaMetric (mathematics)Metric differentialFisher information metricMathematicsInternational Journal of Analysis
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Characterizations of Orlicz-Sobolev Spaces by Means of Generalized Orlicz-Poincaré Inequalities

2012

Let Φ be anN-function. We show that a functionu∈LΦ(ℝn)belongs to the Orlicz-Sobolev spaceW1,Φ(ℝn)if and only if it satisfies the (generalized) Φ-Poincaré inequality. Under more restrictive assumptions on Φ, an analog of the result holds in a general metric measure space setting.

Discrete mathematicsArticle Subjectlcsh:MathematicsFunction (mathematics)Space (mathematics)lcsh:QA1-939Measure (mathematics)Sobolev spacesymbols.namesakePoincaré conjectureMetric (mathematics)symbolsAnalysisMathematicsJournal of Function Spaces and Applications
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On a theorem of Khan in a generalized metric space

2013

Existence and uniqueness of fixed points are established for a mapping satisfying a contractive condition involving a rational expression on a generalized metric space. Several particular cases and applications as well as some illustrative examples are given.

Discrete mathematicsArticle Subjectlcsh:MathematicsInjective metric spacerational expression.Pseudometric spaceFixed pointFixed pointlcsh:QA1-939Convex metric spaceMetric spaceSettore MAT/05 - Analisi MatematicaMetric (mathematics)Uniquenessgeneralized metric spaceMetric differentialMathematics
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Uncertainty measures—Problems concerning additivity

2009

Additivity of an uncertainty measure on an MV-algebra has a clear meaning. If the divisibility is dropped, we come up to a so-called Girard algebra. There we discuss strong resp. weak additivity based on so-called divisible disjoint unions resp. on additivity for all sub-MV-algebras. We obtain a description of those extensions from additive measures on an MV-algebra to the canonical Girard algebra extension of pairs which are strongly additive and valuation measures. Finally, we prove the non-existence of strongly additive measure extensions, if the underlying MV-algebra is a finite chain with more than two non-trivial elements.

Discrete mathematicsArtificial IntelligenceLogicAdditive functionMV-algebraExtension (predicate logic)Divisibility ruleDisjoint setsSigma additivityMeasure (mathematics)Valuation (algebra)MathematicsFuzzy Sets and Systems
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Measure-free conditioning and extensions of additive measures on finite MV-algebras

2010

Using the well known representation of any finite MV-algebra as a product of finite MV-chains as factors, we obtain a representation of its canonical extension as a Girard algebra product of the canonical extensions of the MV-chain factors. Based on this representation and using the results from our last paper, we characterize the additive measures on any finite MV-algebra resp. the weakly and the strongly additive measures on its canonical Girard algebra extension, and that as convex combinations of the corresponding measures on the respective factors. After that we apply the results to measure-free defined conditional events which for this reason are considered as elements of the canonica…

Discrete mathematicsArtificial IntelligenceLogicLattice (order)Additive functionFuzzy setRegular polygonInformation processingConditional probabilityProbability distributionFuzzy control systemMathematicsFuzzy Sets and Systems
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Prime Rings Whose Units Satisfy a Group Identity. II

2003

Abstract Let R be a prime ring and 𝒰(R) its group of units. We prove that if 𝒰(R) satisfies a group identity and 𝒰(R) generates R,then either R is a domain or R is isomorphic to the algebra of n × n matrices over a finite field of order d. Moreover the integers n and d depend only on the group identity satisfed by 𝒰(R). This result has been recently proved by C. H. Liu and T. K. Lee (Liu,C. H.; Lee,T. K. Group identities and prime rings generated by units. Comm. Algebra (to appear)) and here we present a new different proof.

Discrete mathematicsAssociated primeAlgebra and Number TheoryFinite fieldGroup (mathematics)Prime ringA domainOrder (group theory)SubringPrime (order theory)MathematicsCommunications in Algebra
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Analysis of Optimal High Resolution and Fixed Rate Scalar Quantization

2009

In 2001, Hui and Neuhoff proposed a uniform quantizer with overload for the quantization of scalar signals and derived the asymptotically optimal size of the quantization bins in the high-bitrate limit. The purpose of the present paper is to prove a quantitatively more precise version of this result which, at the same time, is valid for a more general, quite natural class of probability distributions that requires only little regularity and includes, for instance, positive Lipschitz-continuous functions of unit integral.

Discrete mathematicsAsymptotically optimal algorithmScalar quantizationQuantization (signal processing)Applied mathematicsHigh resolutionProbability distributionLibrary and Information SciencesInformation theoryNatural classComputer Science ApplicationsInformation SystemsMathematicsIEEE Transactions on Information Theory
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Divisible designs from semifield planes

2002

AbstractWe give a general method to construct divisible designs from semifield planes and we use this technique to construct some divisible designs. In particular, we give the case of twisted field plane as an example.

Discrete mathematicsAutomorphism groupGeneral methodDivisible designsField (mathematics)Division (mathematics)Permutation groupTranslation (geometry)Plane (Unicode)Theoretical Computer ScienceR-permutation groupsCombinatoricsDiscrete Mathematics and CombinatoricsAutomorphism groupsTranslation planesDivision algebrasSemifieldMathematicsDiscrete Mathematics
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Algorithmic Information Theory and Computational Complexity

2013

We present examples where theorems on complexity of computation are proved using methods in algorithmic information theory. The first example is a non-effective construction of a language for which the size of any deterministic finite automaton exceeds the size of a probabilistic finite automaton with a bounded error exponentially. The second example refers to frequency computation. Frequency computation was introduced by Rose and McNaughton in early sixties and developed by Trakhtenbrot, Kinber, Degtev, Wechsung, Hinrichs and others. A transducer is a finite-state automaton with an input and an output. We consider the possibilities of probabilistic and frequency transducers and prove sever…

Discrete mathematicsAverage-case complexityAlgorithmic information theoryTheoryofComputation_COMPUTATIONBYABSTRACTDEVICESKolmogorov complexityDescriptive complexity theoryComputational physicsStructural complexity theoryTheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGESDeterministic finite automatonAsymptotic computational complexityComputer Science::Formal Languages and Automata TheoryComputational number theoryMathematics
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Transition Function Complexity of Finite Automata

2011

State complexity of finite automata in some cases gives the same complexity value for automata which intuitively seem to have completely different complexities. In this paper we consider a new measure of descriptional complexity of finite automata -- BC-complexity. Comparison of it with the state complexity is carried out here as well as some interesting minimization properties are discussed. It is shown that minimization of the number of states can lead to a superpolynomial increase of BC-complexity.

Discrete mathematicsAverage-case complexityTheoryofComputation_COMPUTATIONBYABSTRACTDEVICESFinite-state machineDFA minimizationContinuous spatial automatonAutomata theoryQuantum finite automataDescriptive complexity theoryω-automatonComputer Science::Formal Languages and Automata TheoryMathematics
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