Search results for "Measurement"

showing 10 items of 2918 documents

Measurement issues on harmonic analysis according to the IEC 61000-4-7

2022

The objective of this article is an analysis of measurement issues related to the implementation of digital signal processing techniques for harmonic analysis, by means of FFT algorithm with different interpolation algorithms (linear, quadratic and cubic) and different sampling rates. A comparative analysis is made on errors on harmonics measurement obtained in the various case study analyses. Such errors are compared with the IEC 61000-4-7 limits. The study is supported by both simulation and experimental tests; these last are performed with different acquisition boards for signals acquisition.

Harmonic analysisIEC 61000-4-7power qualitypower system measurementsSettore ING-INF/07 - Misure Elettriche E Elettroniche
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Major Differences in Minor Allometries: A Reply to Moczek.

2018

Abstract: By comparing alternative measurements of horn length in the beetle Onthophagus taurus, we have investigated why scaling patterns differ between laboratories. We show that some measurements are confounded by including part of the head in the horn size measurement and consistently underestimate the allometry of horns in minor males. Our data show how linear measures that avoid confounding horn length with head size produce scaling patterns that support a positive allometry rather than a reprogramming model of horn growth. We also found horn volume was highly positively allometric this estimate of growth therefore further supports a positive allometry model.

Head sizenervous systembiologyEcologyHorn (anatomy)ZoologyOnthophagus taurusAllometrySize measurementbiology.organism_classificationEcology Evolution Behavior and SystematicsThe American naturalist
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What Is the Color of Milk and Dairy Products and How Is It Measured?

2020

Exactly six-hundred (600) scientific articles that report milk and milk products’ color results in scientific journals in the last couple of decades were reviewed. Thereof, the greatest part of the articles derived from Europe (36.3%) and Asia (29.5%). The greatest share of researchers used Minolta colorimeters (58.8%), while 26.3% of them used Hunter devices. Most reports were on cheese (31.0%) followed by fermented products (21.2%). Moreover, the highest number of papers reported color data of milk and milk products made from cow’s milk (44.81%). As expected, goat’s cheese was the brightest (L* = 87.1), while cow’s cheese was the yellowest (b* = 17.4). Most importantly, it appeared that c…

Health (social science)0402 animal and dairy scienceilluminantStandard illuminant04 agricultural and veterinary sciencesPlant ScienceReviewcomputer vision systemaperturemilk color measurementlcsh:Chemical technology040401 food science040201 dairy & animal scienceHealth Professions (miscellaneous)Microbiology0404 agricultural biotechnologyAnimal scienceMilk productsColor datacolorimeterlcsh:TP1-1185Food ScienceMathematics
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Measuring the Rate of Information Transfer in Point-Process Data: Application to Cardiovascular Interactions

2021

We present the implementation to cardiovascular variability of a method for the information-theoretic estimation of the directed interactions between event-based data. The method allows to compute the transfer entropy rate (TER) from a source to a target point process in continuous time, thus overcoming the severe limitations associated with time discretization of event-based processes. In this work, the method is evaluated on coupled cardiovascular point processes representing the heartbeat dynamics and the related peripheral pulsation, first using a physiologically-based simulation model and then studying real point-process data from healthy subjects monitored at rest and during postural …

Heart RateEntropyHumansComputer SimulationHeartEstimation Big Data applications Data models Time measurement Pressure measurement Biomedical monitoring Heart rate variability
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Analysis and Improving Methods of Efficiency of Solar Energy in Municipal Heating System

2011

This paper introduces the current state of solar heating system among Wanzleben city heating net. In view of low efficiency (only 20-30%) of this system, it analyses the shortcomings of this applied system from sensors' situation, fixed flow problem, the influence of the user's water temperature and the length of pipe separately. Some improving methods which are effective by theoretical analysis are suggested. The implementation steps have to be discussed in more detail with the utility.

Heating systemWaste managementbusiness.industryFlow (psychology)Renewable heatEnvironmental sciencePassive solar building designCurrent (fluid)Process engineeringbusinessSolar energyTemperature measurementStorage water heater2011 Asia-Pacific Power and Energy Engineering Conference
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Testing for goodness rather than lack of fit of an X–chromosomal SNP to the Hardy-Weinberg model

2019

The problem of checking the genotype distribution obtained for some diallelic marker for compatibility with the Hardy-Weinberg equilibrium (HWE) condition arises also for loci on the X chromosome. The possible genotypes depend on the sex of the individual in this case: for females, the genotype distribution is trinomial, as in the case of an autosomal locus, whereas a binomial proportion is observed for males. Like in genetic association studies with autosomal SNPs, interest is typically in establishing approximate compatibility of the observed genotype frequencies with HWE. This requires to replace traditional methods tailored for detecting lack of fit to the model with an equivalence test…

HeredityNormal DistributionDistance MeasurementTrinomial01 natural sciencesLinkage Disequilibrium010104 statistics & probabilityStatisticsLack-of-fit sum of squaresMathematicsVenous ThrombosisMeasurement0303 health sciencesMultidisciplinaryQRSoftware EngineeringGenomicsHardy–Weinberg principleGenetic MappingPhysical SciencesEngineering and TechnologyMedicineResearch ArticleComputer and Information SciencesScienceGeometryAsymptotic distributionVariant GenotypesPolymorphism Single NucleotideMolecular Genetics03 medical and health sciencesGenome-Wide Association StudiesGeneticsTest statisticHumansComputer Simulation0101 mathematicsMolecular BiologyGenetic Association Studies030304 developmental biologyChromosomes Human XModels StatisticalModels GeneticSoftware ToolsBiology and Life SciencesComputational BiologyHuman GeneticsGenome AnalysisProbability TheoryProbability DistributionGenotype frequencyRadiiSample size determinationSample SizeBinomial proportion confidence intervalMathematicsPLOS ONE
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Pelvic girdle pain affects the whole life—A qualitative interview study in Norway on women’s experiences with pelvic girdle pain after delivery

2014

Background The aim of this study was to explore how pelvic girdle pain after delivery influences women’s daily life in Norway. Knowledge about living with post-partum pelvic girdle pain is lacking. Method A phenomenological–hermeneutical design with qualitative semi-structured interviews was used. A strategic selection procedure was chosen to recruit participants from physiotherapy clinics and a regional hospital in Norway. Five women with clinically verified pelvic girdle pain after delivery were included. Data were imported into NVivo9 and analysed in three steps: naïve reading, structural analysis and comprehensive understanding of the text. Results Three themes influencing the women’s d…

HermeneuticsAdultHealth Knowledge Attitudes PracticeEmotionsHealth BehaviorInterviews as TopicDisability EvaluationPelvic Girdle PainCost of IllnessPregnancyActivities of Daily LivingAdaptation PsychologicalVDP::Medical disciplines: 700::Clinical medical disciplines: 750::Gynecology and obstetrics: 756HumansPain MeasurementMedicine(all)NorwayBiochemistry Genetics and Molecular Biology(all)Postpartum PeriodSocial SupportMiddle AgedDelivery ObstetricQuality of LifePhenomenologyFemaleResearch ArticlePost-partum
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1.6 GHz VLBI observations of SN 1979C: almost-free expansion

2009

We report on 1.6 GHz Very-Long-Baseline-Interferometry (VLBI) observations of supernova SN 1979C made on 18 November 2002. We derive a model-dependent supernova size. We also present a reanalysis of VLBI observations made by us on June 1999 and by other authors on February 2005. We conclude that, contrary to our earlier claim of strong deceleration in the expansion, SN 1979C has been undergoing almost-free expansion ($m = 0.91\pm0.09$; $R \propto t^m$) for over 25 years.

High Energy Astrophysical Phenomena (astro-ph.HE)PhysicsCosmology and Nongalactic Astrophysics (astro-ph.CO)Continuum (measurement)FOS: Physical sciencesAstronomy and AstrophysicsAstrophysicsSupernovaSpace and Planetary ScienceVery-long-baseline interferometryFree expansionBasso continuoAstrophysics - High Energy Astrophysical PhenomenaAstrophysics - Cosmology and Nongalactic AstrophysicsAstronomy & Astrophysics
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High energy neutrino telescopes in the Northern Hemisphere

2012

We review the status and results of the high energy neutrino telescopes in the Northern Hemisphere, namely ANTARES and Baikal (NT200+).

High Energy Astrophysical Phenomena (astro-ph.HE)PhysicsNuclear and High Energy PhysicsPhysics::Instrumentation and DetectorsSolar neutrinoAstrophysics::High Energy Astrophysical PhenomenaDark matterAstrophysics::Instrumentation and Methods for AstrophysicsFOS: Physical sciencesAstronomyFísicaAstrophysicsSolar neutrino problemPhysics::GeophysicsNeutrino detectorMeasurements of neutrino speedHigh Energy Physics::ExperimentNeutrino astronomyNeutrinoAstrophysics - High Energy Astrophysical PhenomenaNeutrino oscillationInstrumentationAstrophysics::Galaxy Astrophysics
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Production of keV sterile neutrinos in supernovae: New constraints and gamma-ray observables

2019

We study the production of sterile neutrinos in supernovae, focusing in particular on the keV--MeV mass range, which is the most interesting range if sterile neutrinos are to account for the dark matter in the Universe. Focusing on the simplest scenario in which sterile neutrinos mixes only with muon or tau neutrino, we argue that the production of keV--MeV sterile neutrinos can be strongly enhanced by a Mikheyev--Smirnov--Wolfenstein (MSW) resonance, so that a substantial flux is expected to emerge from a supernova, even if vacuum mixing angles between active and sterile neutrinos are tiny. Using energetics arguments, this yields limits on the sterile neutrino parameter space that reach do…

High Energy Astrophysical Phenomena (astro-ph.HE)PhysicsSterile neutrinoParticle physicsPhysics::Instrumentation and Detectors010308 nuclear & particles physicsAstrophysics::High Energy Astrophysical PhenomenaSolar neutrinoHigh Energy Physics::PhenomenologyFOS: Physical sciencesSolar neutrino problemComputer Science::Digital Libraries7. Clean energy01 natural sciencesCosmic neutrino backgroundHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)Neutrino detector0103 physical sciencesMeasurements of neutrino speedHigh Energy Physics::ExperimentNeutrino astronomyNeutrinoAstrophysics - High Energy Astrophysical Phenomena010303 astronomy & astrophysicsPhysical Review D
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