Search results for "NUMB"

showing 10 items of 3956 documents

Structure and Photocatalytic Properties of TiO2-WO3Composites Prepared by Electrophoretic Deposition

2015

In this work TiO2-WO3 composite films containing different oxide concentrations were prepared by electrophoretic deposition on steel substrates. Composite coating structures were analyzed by X -ray diffraction, Raman spectra and scanning electron microscopy. The results showed an even distribution of WO3 particles in the entire composite layer. Light absorption measurements were used for photocatalytic properties evaluation. It was found that the removal ratio of methylene blue depends on the (TiO2):(WO3) concentration ratio. The most effective photodegradation was determined for the sample that was electrophoretically deposited from the suspension with the molar content ratio n(TiO2):n(WO3…

symbols.namesakeElectrophoretic depositionMaterials scienceScanning electron microscopeComposite numbersymbolsPhotocatalysisAnalytical chemistryRaman spectroscopyPhotodegradationLayer (electronics)Concentration ratioNuclear chemistryIOP Conference Series: Materials Science and Engineering
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On Stability of a Concentrated Fiber Suspension Flow

2014

Linear stability analysis of a fiber suspension flow in a channel domain is performed using a modified Folgar-Tucker equation. Two kinds of potential instability are identified: one is associated with overcritical Reynolds number and another is associated with certain perturbations in fiber orientation field and is present for any Reynolds numbers. The second type of instability leads to initially growing transient perturbations in the microstructure. It is shown that both types of instability lead to instability of the bulk velocity field. As for the perturbed Orr-Sommerfeld eigenvalues, the presence of fibers increases the stability region; the stability region increases with growing C i …

symbols.namesakeMaterials scienceField (physics)Flow (psychology)symbolsReynolds numberMechanicsTransient (oscillation)MicrostructureStability (probability)InstabilityEigenvalues and eigenvectors
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High Resolution Coherent Raman Spectroscopy: Studies of Molecular Structures

1992

One of the main advantages of the non-linear coherent Raman techniques is the high resolution that can be achieved in rovibrational spectroscopy. Typically an instrumental function of the order of several thousandths of a wavenumber is routinely achieved in SRS or CARS experiments. Since the first recording of the stimulated Raman spectrum of 12CH4 in 1978 [1], numerous studies of molecules have been performed [2–8]. We have built a stimulated Raman experiment in Dijon in which particular attention has been paid to the frequency measurement of the Raman lines [9]. We will describe the application of our experiment to a wide variety of molecules over the last few years: linear molecules, sph…

symbols.namesakeMaterials sciencesymbolsWavenumberMoleculeLinear molecular geometryRotational–vibrational spectroscopyCoherent anti-Stokes Raman spectroscopyAtomic physicsRaman spectroscopyCoherent spectroscopySpectroscopy
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Weak Maximum Principle and Application to Swimming at Low Reynolds Number

2018

We refer to [9, 42, 46] for more details about the general concepts and notations introduced in this section.

symbols.namesakeMaximum principleSection (archaeology)Mathematical analysissymbolsReynolds numberMathematics
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A Leibniz variety with almost polynomial growth

2005

Abstract Let F be a field of characteristic zero. In this paper we study the variety of Leibniz algebras V ˜ 1 defined by the identity y 1 ( y 2 y 3 ) ( y 4 y 5 ) ≡ 0 . We give a complete description of the space of multilinear identities in the language of Young diagrams through the representation theory of the symmetric group. As an outcome we show that the variety V ˜ 1 has almost polynomial growth, i.e., the sequence of codimensions of V ˜ 1 cannot be bounded by any polynomial function but any proper subvariety of V ˜ 1 as polynomial growth.

symbols.namesakePure mathematicsAlgebra and Number TheoryInvariant polynomialSymmetric polynomialAlternating polynomialLeibniz formula for determinantsHomogeneous polynomialsymbolsElementary symmetric polynomialPolarization of an algebraic formMathematicsSquare-free polynomialJournal of Pure and Applied Algebra
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Liftings and extensions of operators in Brownian setting

2020

We investigate the operators T on a Hilbert space H which have 2-isometric liftings S with the property S ∗ S H ⊂ H . We show that such liftings are closely related to some extensions of T, which h...

symbols.namesakePure mathematicsAlgebra and Number TheoryProperty (philosophy)Mathematics::Operator AlgebrasHilbert spacesymbols010103 numerical & computational mathematicsExtension (predicate logic)0101 mathematics01 natural sciencesBrownian motionMathematicsLinear and Multilinear Algebra
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A novel heuristic memetic clustering algorithm

2013

In this paper we introduce a novel clustering algorithm based on the Memetic Algorithm meta-heuristic wherein clusters are iteratively evolved using a novel single operator employing a combination of heuristics. Several heuristics are described and employed for the three types of selections used in the operator. The algorithm was exhaustively tested on three benchmark problems and compared to a classical clustering algorithm (k-Medoids) using the same performance metrics. The results show that our clustering algorithm consistently provides better clustering solutions with less computational effort.

ta113Determining the number of clusters in a data setBiclusteringClustering high-dimensional dataDBSCANComputingMethodologies_PATTERNRECOGNITIONTheoretical computer scienceCURE data clustering algorithmCorrelation clusteringCanopy clustering algorithmCluster analysisAlgorithmMathematics2013 IEEE International Workshop on Machine Learning for Signal Processing (MLSP)
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An efficient cluster-based outdoor user positioning using LTE and WLAN signal strengths

2015

In this paper we propose a novel cluster-based RF fingerprinting method for outdoor user-equipment (UE) positioning using both LTE and WLAN signals. It uses a simple cost effective agglomerative hierarchical clustering with Davies-Bouldin criterion to select the optimal cluster number. The positioning method does not require training signature formation prior to UE position estimation phase. It is capable of reducing the search space for clustering operation by using LTE cell-ID searching criteria. This enables the method to estimate UE positioning in short time with less computational expense. To validate the cluster-based positioning real-time field measurements were collected using readi…

ta113SIMPLE (military communications protocol)business.industryComputer scienceReal-time computingLTE cell-IDFingerprint recognitionGridminimization of drive testsDetermining the number of clusters in a data setEmbedded systemgrid-based RF fingerprintingRadio frequencybusinessCluster analysishierarchical clustering
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Context–content systems of random variables : The Contextuality-by-Default theory

2016

Abstract This paper provides a systematic yet accessible presentation of the Contextuality-by-Default theory. The consideration is confined to finite systems of categorical random variables, which allows us to focus on the basics of the theory without using full-scale measure-theoretic language. Contextuality-by-Default is a theory of random variables identified by their contents and their contexts, so that two variables have a joint distribution if and only if they share a context. Intuitively, the content of a random variable is the entity the random variable measures or responds to, while the context is formed by the conditions under which these measurements or responses are obtained. A …

ta113Theoretical computer scienceComputer scienceApplied Mathematicscouplings05 social sciencesta111Probabilistic logicContext (language use)01 natural sciencesMeasure (mathematics)050105 experimental psychologyconnectednessKochen–Specker theoremrandom variablesJoint probability distribution0103 physical sciences0501 psychology and cognitive sciencescontextualityNegative number010306 general physicsCategorical variableRandom variableGeneral PsychologyJournal of Mathematical Psychology
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On optimal relay placement for improved performance in non-coverage limited scenarios

2014

Low power nodes have been a hot topic in research, standardization, and industry communities, which is typically considered under an umbrella term called heterogeneous networking. In this paper we look at the problem of deploying optimally low power nodes in the context of relay networking, when an operator connects low power nodes (or small cells) via the wireless backhaul that uses the same spectrum and the same wireless access technology. We present an analytical model that can calculate optimal coordinates for low power nodes based on the input parameters, such as preferred number of nodes, their transmission power, parameters of the environment etc. The analytical calculations are comp…

ta113business.industryComputer sciencePreferred numberUmbrella termContext (language use)law.inventionPower (physics)Operator (computer programming)Transmission (telecommunications)RelaylawWirelessbusinessComputer network
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