Search results for "Measurement"

showing 10 items of 2918 documents

Metrological performances of voltage and current instrument transformers in harmonics measurements

2018

In the new electrical system scenario, the increasing presence of non-linear loads and renewable energy sources makes the measurement of harmonics an essential task. The accuracy of harmonic measurement firstly depends on the used instrument transformers for voltage and current sensing. Since the behavior of instrument transformers in non-sinusoidal conditions is not always well defined, this paper presents an experimental study on the metrological performances of current and voltage instrument transformers (CTs and VTs) in the presence of harmonics. Proper tests procedures are defined and measurement setups are developed for both CTs and VTs calibration. The analysis is carried out by usin…

instrument transformers020209 energy02 engineering and technologyInstrument TransformerHarmonic analysispower system meaurementsPhase AngleDistortionharmonics0202 electrical engineering electronic engineering information engineeringCalibrationElectronic engineeringMedicineSafety Risk Reliability and QualityInstrumentationbusiness.industry020208 electrical & electronic engineeringHarmonicPower System MeasurementcalibrationCurrent transformerMetrologyHarmonicsHarmonicbusinessSettore ING-INF/07 - Misure Elettriche E ElettronicheVoltage
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Current transformers effects on the measurement of harmonic active power in LV and MV networks

2011

The harmonic active power is used to determine the location of polluting loads, the direction of harmonic power flow and to estimate how consequential a certain current harmonic source is. The highest uncertainties, when measuring harmonic active power, are introduced by the current and voltage transducers. This paper presents experimental results which show the impact of current transformers (CTs) on the accuracy of the harmonic power measurements. An expression for the evaluation of the power error in distorted conditions was developed which can be easily utilized in the case of linear current transducers. It is shown how CTs cannot be considered linear transducers and how the higher the …

instrument transformersEngineeringVoltage and current harmonicsSwitched-mode power supplyAcousticsActive powerTransducersEnergy Engineering and Power TechnologyLinear currentsPower factorHarmonic powerLinear transducersPower errorsPower transformersVoltage transducersHarmonic analysisHarmonic analysisMaximum valuesCurrent transformerElectrical and Electronic EngineeringPower measurementPhase anglesAbsolute valuesHarmonic power flowTotal harmonic distortionbusiness.industryElectric power distributionCurrent harmonicsElectrical engineeringAC powerCurrent transformerMV networksHarmonicsAccuracy classElectric instrument transformersHarmonicPower system harmonicsCurrent transformers (CTs) instrument transformerspower measurement power system harmonics.businessSettore ING-INF/07 - Misure Elettriche E Elettroniche
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Musculoskeletal pain in professional orchestra instrumentalists and its determinants: a Polish pilot study

2022

Introduction: This study aimed to assess pain in professional musicians playing various instruments, as well as to analyse the relationships between the intensity and frequency of pain and the duration of playing the instrument and somatic variables. Materials and methods: A cross-sectional study was conducted between 60 professional musicians, who were divided into 3 groups: cellists, violinists, and musicians playing wind instruments. Pain intensity was assessed using the visual analogue scale (VAS). The respondents also assessed the frequency of musculoskeletal disorders, the location of pain, the number of hours of playing the instrument per week, and the playing experience in years. In…

instrumentalistsoccupational healthmusculoskeletal painpain measurementPomeranian Journal of Life Sciences
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VERS UNE ARCHITECTURE UNIFIÉE ET ZÉRO TEMPS MORT POUR L'INSTRUMENTATION NUCLÉAIRE

2014

National audience; Dans l’instrumentation nucléaire, et d’autres domaines tels que les applications de la physique des particules, l’analyse de signaux médicaux (Tomographie par Emission de Positons (TEP), Electro-EncephaloGraphie (EEG)) ou la détection de signaux radar, le signal mesuré est composé d’impulsions dont la date d’arrivée est aléatoire, et dont l’amplitude et la durée sont non-d´eterministes. La grande variété d’applications nécessite de disposer d’une architecture flexible pouvant être aisément reprogrammée. De plus, l’exigence de mesures en temps réel impose de disposer d’une grande capacité de calcul et de bande passante pour la mise en forme et l’extraction des caractéristi…

instrumentation[INFO.INFO-AR]Computer Science [cs]/Hardware Architecture [cs.AR][INFO.INFO-AR] Computer Science [cs]/Hardware Architecture [cs.AR][ INFO.INFO-TS ] Computer Science [cs]/Signal and Image Processing[INFO.INFO-TS] Computer Science [cs]/Signal and Image ProcessingDigital Pulse Processing[SPI.TRON] Engineering Sciences [physics]/Electronicselectronic architecture[ SPI.TRON ] Engineering Sciences [physics]/Electronics[SPI.TRON]Engineering Sciences [physics]/Electronicsreal time measurementimpulse separation[INFO.INFO-TS]Computer Science [cs]/Signal and Image ProcessingDigital Signal Processing[ INFO.INFO-AR ] Computer Science [cs]/Hardware Architecture [cs.AR]Digital Architecturesignal processingnuclear instrumentation
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Social Desirability Bias among Prejudice Instruments : An Integrated Threat

2019

A considerable amount of research has examined the extent to which members of dominant cultures perceive minority groups as threatening their way of life. While various instruments measure these perceptions of threat, few researchers have empirically analysed the statistical properties of these scales. Specifically, studies have not adequately explored social desirability of threat scales. The current study investigates the extent to which one set of threat scales is internally consistent or reliable (González et al., 2008), and explores social desirability within the González et al. (2008) integrated threat instruments by comparing self-reports to other reports (intimate other and friend r…

integrated threat theoryennakkoluulotvähemmistötmittarit (mittaus)reliability analysismeasurementprejudiceuhkakuvatreliabiliteetti
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Experimentelle Bestimmung der Gleitreibungskräfte beim Einschlagen von Oberschenkelmarknägeln

1990

No data have published concerning the procedure of driving in intramedullary nails. An extensive experimental device consisting of a contact-free distance measurement, a dynamograph connected to strain gages and an accelerometer now enabled this investigation. Among other things we determined the range of sliding friction for each stroke at different levels of nail-progression. Depending of the depth of nail-progression forces between 200 N und 400 N were measured. When the nail is stuck these values rise to over 1000 N. The sliding-process lasted between 10 ms and 20 ms. Knowledge of these data is of major importance for improvement of surgical technique and possible development of mechani…

integumentary systembusiness.industryAccelerometerlaw.inventionIntramedullary rodStress (mechanics)Distance measurementlawFracture fixationNail (fastener)MedicineSurgeryskin and connective tissue diseasesbusinessStrain gaugeBiomedical engineeringUnfallchirurgie
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On the characterization of some [bmim][X]/co-solvent binary mixtures: a multidisciplinary approach by using kinetic, spectrophotometric and conductom…

2008

Abstract In order to study the intrinsic characteristics and to evaluate the structural variations determined by the addition of a co-solvent to 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF 4 ]) we examined the behaviour of some probes in [bmim][BF 4 ]/co-solvent binary mixtures. The rate constants of the piperidino-catalyzed rearrangement of the Z -phenylhydrazone of the 3-benzoyl-5-phenyl-1,2,4-oxadiazole into the relevant 4-benzoylamino-2,5-diphenyl-1,2,3-triazole as well as the spectrometric properties of pyrene and Nile Red were evaluated. With the same purpose also 1 H NMR and conductivity measurements were carried out. By comparison the behaviour of 1-butyl-3-methylimidaz…

ionic liquids binary mixtures MHR reaction spectrophometric measurementsTetrafluoroborateChemistryOrganic ChemistryNile redAnalytical chemistrySettore CHIM/06 - Chimica OrganicaConductivityBiochemistrychemistry.chemical_compoundReaction rate constantDrug DiscoveryIonic liquidProton NMRPyreneMoleculeTetrahedron
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Ionic Liquids binary mixtures: the influence of the composition on their properties and catalytic ability

ionic liquids kinetic measurements NMR and RLS investigationSettore CHIM/06 - Chimica Organica
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Organisaatioiden isomorfismi : julkiset organisaatiot ja yhdenmukaisuuden paine

2018

isomorfismiisomorphismyksityinen sektorituloksellisuustehokkuustyöntekijätorganisaatiotperformance measurementsyhdenmukaisuusjulkinen sektori
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Interim Financial Reporting in the Perspective of harmonization of the Romanian Accountancy with the International Financial Reporting Standards

2007

The main objective of the interim financial reporting is to present, timely and regularly, information concerning the enterprise’s capacity to generate earnings and cash flows and its financial position and liquidity. International Accounting Standard 34 “Interim Financial Reporting” concerns the financial statements for an interim period. According to IAS 34, the interim financial report includes a complete or condensed set of financial statements, elaborated for a shorter period than a full financial year. The accounting policies for recognition and measurement should be applied in the same way as they are applied in the annual financial statements. However, the preparation of the interim…

jel:M41interim financial reporting interim report interim period recognition measurement
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