Search results for " EFFICIENCY"

showing 10 items of 1091 documents

Routing Algorithm for Maximizing Lifetime of Wireless Sensor Network for Broadcast Transmission

2018

In the article we discuss solutions of the maximum lifetime broadcasting problem in wireless sensor networks. Due to limited energy resources of the network nodes to find an optimal transmission route of the broadcasted data we minimize the maximum energy consumed by the nodes. We give an analytical solution of the problem in one dimensional regular sensor network for the point-to-point and point-to-multipoint data transmission scheme. We show that in such a network, when the cost of data transmission is a polynomial function of distance between transmitter and receiver, there exist solutions with an equal energy, i.e., all nodes of the network consume the same amount of energy. We assume t…

Spanning treeComputer scienceNode (networking)Wireless communication020206 networking & telecommunications02 engineering and technologyEnergy consumptionTopologyComputer Science ApplicationsBroadcast transmissionBroadcasting (networking)Energy efficiencyTransmission (telecommunications)0202 electrical engineering electronic engineering information engineering020201 artificial intelligence & image processingSensor network lifetimeElectrical and Electronic EngineeringTime complexityWireless sensor networkData transmissionWireless Personal Communications
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Reducing complexity in H.264/AVC motion estimation by using a GPU

2011

H.264/AVC applies a complex mode decision technique that has high computational complexity in order to reduce the temporal redundancies of video sequences. Several algorithms have been proposed in the literature in recent years with the aim of accelerating this part of the encoding process. Recently, with the emergence of many-core processors or accelerators, a new approach can be adopted for reducing the complexity of the H.264/AVC encoding algorithm. This paper focuses on reducing the inter prediction complexity adopted in H.264/AVC and proposes a GPU-based implementation using CUDA. Experimental results show that the proposed approach reduces the complexity by as much as 99% (100x of spe…

SpeedupComputational complexity theoryComputer science020206 networking & telecommunicationsData_CODINGANDINFORMATIONTHEORY02 engineering and technologyParallel computingCUDAAlgorithmic efficiency0202 electrical engineering electronic engineering information engineeringWorst-case complexity020201 artificial intelligence & image processingContext-adaptive binary arithmetic codingData compressionContext-adaptive variable-length coding
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The performance of the cryogenic buffer-gas stopping cell of SHIPTRAP

2018

Direct high-precision mass spectrometry of the heaviest elements with SHIPTRAP, at GSI in Darmstadt, Germany, requires high efficiency to deal with the low production rates of such exotic nuclides. A second-generation gas stopping cell, operating at cryogenic temperatures, was developed and recently integrated into the relocated system to boost the overall efficiency. Offline measurements using 223Ra and 225Ac recoil-ion sources placed inside the gas volume were performed to characterize the gas stopping cell with respect to purity and extraction efficiency. In addition, a first online test using the fusion-evaporation residue 254No was performed, resulting in a combined stopping and extrac…

Speichertechnik - Abteilung BlaumNuclear and High Energy PhysicsMaterials scienceDIRECT MASS MEASUREMENTSProtonBuffer gaschemistry.chemical_elementPenning trapsMass spectrometry7. Clean energy01 natural sciencesFusion-evaporation reaction productsNuclear physicsIonization0103 physical sciencesCalibrationStopping and extraction efficiencyNuclide010306 general physicsInstrumentationCALIBRATION[PHYS]Physics [physics]nobeliumSPECTROSCOPYMass spectrometry010308 nuclear & particles physicsTransfermium elementsCryogenic gas stopping cellExtraction timeHEAVIEST ELEMENTSchemistryIONIZATIONNobeliumOrder of magnitude
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PV effect of fullerene/poly(3-hexylthiophene) blend sensitized by phthalocyanine having infrared absorption CT band

2008

An attempt was made to extend the photosensitivity spectral range of fullerene/poly(3-hexylthiophene) blend to NIR region by adding extra electron donor — hydroxygallium phthalocyanine (GaOHPc) with a strong and wide intermolecular charge transfer (CT) band around 830 nm. Multilayer cells of ITO/PEDOT: PSS/6 GaOHPc/P3HT: C61(CO2Et)2 have been prepared by spin coating with vacuum evaporated Al or In top electrodes. Significant photosensitivity of the cells was in 370–900 nm spectral range. However charge carrier photogeneration efficiency was 3 times higher for illumination in P3HT absorption band as compared with the GaOHPc CT band at 830 nm. But when GaOHPc was mixed in the blend forming P…

Spin coatingMaterials sciencebusiness.industryPhotochemistryPolymer solar cellchemistry.chemical_compoundPhotosensitivityPEDOT:PSSchemistryAbsorption bandPhthalocyanineOptoelectronicsQuantum efficiencyCharge carrierbusiness
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A Comparison of Formulae for Calculating Cost-Efficient Sample Sizes of Case-Control Studies with an Internal Validation Scheme

2000

When a case-control study is planned to include an internal validation study, the sample size of the study and the proportion of validated observations has to be calculated. There are a variety of alternative methods to accomplish this. In this article some possible procedures will be compared in order to clarify whether considerable differences in the suggested optimal designs occur, dependent on the used method.

Statistics and ProbabilityAlternative methodsScheme (programming language)Optimal designMathematical optimizationCost efficiencyEstimation theoryComputer scienceSmall sampleGeneral MedicineSample size determinationStatisticsStatistics Probability and UncertaintyInternal validationcomputercomputer.programming_languageBiometrical Journal
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Sign test of independence between two random vectors

2003

A new affine invariant extension of the quadrant test statistic Blomqvist (Ann. Math. Statist. 21 (1950) 593) based on spatial signs is proposed for testing the hypothesis of independence. In the elliptic case, the new test statistic is asymptotically equivalent to the interdirection test by Gieser and Randles (J. Amer. Statist. Assoc. 92 (1997) 561) but is easier to compute in practice. Limiting Pitman efficiencies and simulations are used to compare the test to the classical Wilks’ test. peerReviewed

Statistics and ProbabilityDiscrete mathematicsStatistics::TheoryMultivariate random variableExtension (predicate logic)robustnessQuadrant testPitman efficiencyTest (assessment)Exact testStatisticsChi-square testTest statisticSign testaffine invarianceStatistics Probability and UncertaintyIndependence (probability theory)MathematicsWilks’ test
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Characterization of the parameters of interior permanent magnet synchronous motors for a loss model algorithm

2017

Abstract The paper provides the results of a detailed experimental study on the variations of the characteristics of an interior permanent magnet synchronous motor, when load, speed and/or magnetization conditions vary. In particular, the characterization is carried out by assessing, for several working conditions, the motor parameters that influence its efficiency. From the knowledge of the variability of these parameters, it is possible to develop a dynamic model of the motor, which accurately describes its behaviour and allows estimating the power losses for whatever speed and load. In order to validate the model, the values of the power losses obtained by using the model are compared wi…

Statistics and ProbabilityEngineering3304020209 energyCondensed Matter Physic02 engineering and technologySettore ING-IND/32 - Convertitori Macchine E Azionamenti ElettriciControl theoryComponent (UML)0202 electrical engineering electronic engineering information engineeringElectrical and Electronic EngineeringInstrumentationPermanent magnet synchronous motorInterior permanent magnet synchronous motorSpeed control drive systembusiness.industryApplied Mathematics020208 electrical & electronic engineeringInterior permanent magnet synchronous motors; Power loss minimization; Speed control drive systems; Statistics and Probability; 3304; Condensed Matter Physics; Applied MathematicsCondensed Matter PhysicsPower loss minimizationCharacterization (materials science)Power (physics)Settore ING-IND/31 - ElettrotecnicaMotor efficiencySynchronous motorbusinessSettore ING-INF/07 - Misure Elettriche E ElettronicheAlgorithmMeasurement
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A macroeconomic analysis of the public investments in European combined transport

2009

Intermodal transport has been recognized as a priority by the European Union, that has defined different budget allocations of investments to improve the shifting from road to intermodal transport, which is more sustainable. In this context, the main aim of the paper is to discuss the macroeconomic effects, in terms of economic growth, welfare and trade, of these public investments for combined transport, which aspects have been neglected in literature. A multi-country computable general equilibrium model has been used. The main results have been that the European Union benefits from these investments, but at international level, USA and Japan would lose in terms of welfare. Furthermore, th…

Statistics and ProbabilityMacroeconomicsComputable general equilibriumInternational levelEconomics and Econometricsmedia_common.quotation_subjectContext (language use)International economicsComputable general equilibrium model public investments combined transport sensitivity analysisMathematics (miscellaneous)Exchange rateSettore SECS-P/03 - Scienza Delle FinanzeEconomicsmedia_common.cataloged_instanceAllocative efficiencyEuropean unionRobustness (economics)WelfareSocial Sciences (miscellaneous)media_common
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Tests of multinormality based on location vectors and scatter matrices

2007

Classical univariate measures of asymmetry such as Pearson’s (mean-median)/σ or (mean-mode)/σ often measure the standardized distance between two separate location parameters and have been widely used in assessing univariate normality. Similarly, measures of univariate kurtosis are often just ratios of two scale measures. The classical standardized fourth moment and the ratio of the mean deviation to the standard deviation serve as examples. In this paper we consider tests of multinormality which are based on the Mahalanobis distance between two multivariate location vector estimates or on the (matrix) distance between two scatter matrix estimates, respectively. Asymptotic theory is develop…

Statistics and ProbabilityMahalanobis distanceKurtosisUnivariateAsymptotic theory (statistics)SkewnessPitman efficiencyStandard deviationNormal distributionScatter matrixSkewnessAffine invarianceStatisticsKurtosisStatistics Probability and UncertaintyMathematicsStatistical Methods and Applications
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Multivariate nonparametric tests of independence

2005

New test statistics are proposed for testing whether two random vectors are independent. Gieser and Randles, as well as Taskinen, Kankainen, and Oja have introduced and discussed multivariate extensions of the quadrant test of Blomqvist. This article serves as a sequel to this work and presents new multivariate extensions of Kendall's tau and Spearman's rho statistics. Two different approaches are discussed. First, interdirection proportions are used to estimate the cosines of angles between centered observation vectors and between differences of observation vectors. Second, covariances between affine-equivariant multivariate signs and ranks are used. The test statistics arising from these …

Statistics and ProbabilityMultivariate statisticsMultivariate analysisNonparametric statisticsAsymptotic distributionMultivariate normal distributionSpearman's rank correlation coefficientQuadrant testriippumattomuusPitman efficiencyKendall's tauStatisticsHigh-dimensional statisticsaffine invarianceStatistics Probability and UncertaintySpearman's rhoRobustnessMathematicsStatistical hypothesis testing
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