Goldilocks: Consistent Crowdsourced Scalar Annotations with Relative Uncertainty

The aim of this paper is to present a possible experiment for measuring photon number by a non-demolitive scheme. We show that, in principle, it is possible to deduce the number of photons of an intense pump coherent field by measuring the phase-shift on two frequency conjugated beams due to the interaction with the pump in a nonlinear crystal, which exhibits χ(2) nonlinearity. We perform a theoretical evaluation of the relative uncertainty associated to the photon number measurement, obtaining high accuracy results when high pump power levels, low coupling between pump and crystal and squeezing generators are used. The accuracy obtained are compared with results obtainable with a beam splitter setup.

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On Aethalometer measurement uncertainties and multiple scattering enhancement in the Arctic

10.5194/amt-2016-294 ◽

2016 ◽

Cited By ~ 4

Author(s):

John Backman ◽

Lauren Schmeisser ◽

Aki Virkkula ◽

John A. Ogren ◽

Eija Asmi ◽

...

Keyword(s):

Detection Limit ◽

Temporal Resolution ◽

The Arctic ◽

Electronic Noise ◽

Relative Uncertainty ◽

Post Processing ◽

Additional Advantage ◽

Aerosol Absorption ◽

Threshold Criterion ◽

Small Aerosol

Abstract. Several types of filter-based instruments are used to estimate aerosol light absorption coefficients.Two significant results are presented based on Aethalometer measurements at six Arctic station from 2012–2014. First, an alternative method of post-processing the Aethalometer data is presented which reduces measurement noise and lowers the detection limit of the instrument more effectively than boxcar averaging. The biggest benefit of this approach can be achieved if instrument drift is minimized. Moreover, by using an attenuation threshold criterion for data post-processing, the relative uncertainty from the electronic noise the instrument is kept constant. This approach results in a time series with a variable collection time (Δt), but with a constant relative uncertainty with regard to electronic noise in the instrument. An additional advantage of this method is that the detection limit of the instrument will be lowered at small aerosol concentrations at the expense of temporal resolution, whereas there is little to no loss in temporal resolution at high aerosol concentrations (>2.1–6.7 Mm−1 as measured by the Aethalometers). At high aerosol concentrations, minimizing the detection limit of the instrument is less critical. Second, utilizing co-located reference methods of aerosol absorption, a multiple cattering enhancement factor (Cref) of 3.10 specific to low elevation Arctic stations is found. Cref is a fundamental part of most of the Aethalometer corrections available in literature, and this is the first time a Cref value has been obtained for the Arctic.

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Accuracy of Satellite Land Surface Reflectance Determination

Journal of Applied Meteorology ◽

10.1175/1520-0450-30.7.960 ◽

1991 ◽

Vol 30 (7) ◽

pp. 960-972 ◽

Cited By ~ 9

Author(s):

O. Arino ◽

G. Dedieu ◽

P. Y. Deschamps

Keyword(s):

Land Surface ◽

Surface Albedo ◽

Maximum Error ◽

Surface Reflectance ◽

Relative Uncertainty ◽

Calibration Uncertainty ◽

Maximum Bias ◽

Calibration Accuracy ◽

The Difference

Abstract An accuracy budget of the surface reflectance determination from Meteosat geostationary satellite data is performed. Error analysis allows identification of three main problems: calibration uncertainty of the Meteosat instrument, atmospheric corrections, and surface effects (spectral and directional). Calibration accuracy is 10%, leading to a 10% relative uncertainty on reflectance. Spectral effects of the surface lead to a maximum bias of 0.01 for a vegetated surface as sensed by Meteosat, while directional effects can lead to a bias of 0.035 between two measurements taken at two different sun zenith and azimuth angles at the same view angle over savannas. The maximum error due to the atmosphere is estimated to be of the order of 0.03 in reflectance for a surface reflectance of 0.40 and 0.01 for, a surface reflectance of 0.10. Validation with in situ measurement is within the expected error over savanna. But the difference is still high over the southwest France site of HAPEX-MOBILHY, certainly due to the joint spectral and directional errors. Comparisons with surface albedo maps from literature show the same spatial and spatial evolutions with a better spatial and temporal determination in our results.

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Diffusion Coefficients of Methane in Methylbenzene and Heptane at Temperatures between 323 K and 398 K at Pressures up to 65 MPa

International Journal of Thermophysics ◽

10.1007/s10765-020-02700-0 ◽

2020 ◽

Vol 41 (8) ◽

Cited By ~ 2

Author(s):

Malyanah Binti Mohd Taib ◽

J. P. Martin Trusler

Keyword(s):

Diffusion Coefficients ◽

Infinite Dilution ◽

Hydrodynamic Radius ◽

Taylor Dispersion ◽

Relative Uncertainty ◽

Dispersion Method ◽

Solvent Density ◽

Einstein Model ◽

Taylor Dispersion Method ◽

Simple Empirical Model

Abstract We reported experimental measurements of the diffusion coefficient of methane at effectively infinite dilution in methylbenzene and in heptane at temperatures ranging from (323 to 398) K and at pressures up to 65 MPa. The Taylor dispersion method was used and the overall combined standard relative uncertainty was 2.3%. The experimental diffusion coefficients were correlated with a simple empirical model as well as the Stokes–Einstein model with the effective hydrodynamic radius of methane depending linearly upon the solvent density. The new data address key gaps in the literature and may facilitate the development of an improved predictive model for the diffusion coefficients of dilute gaseous solutes in hydrocarbon liquids.

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Depolarization calibration and measurements using the CANDAC Rayleigh–Mie–Raman lidar at Eureka, Canada

Atmospheric Measurement Techniques ◽

10.5194/amt-10-4253-2017 ◽

2017 ◽

Vol 10 (11) ◽

pp. 4253-4277 ◽

Cited By ~ 5

Author(s):

Emily M. McCullough ◽

Robert J. Sica ◽

James R. Drummond ◽

Graeme Nott ◽

Christopher Perro ◽

...

Keyword(s):

Water Vapour ◽

High Arctic ◽

Mueller Matrix ◽

Particle Phase ◽

Relative Uncertainty ◽

Raman Lidar ◽

Canadian High Arctic ◽

Cloud Particle ◽

Measurement Capability ◽

Atmospheric Change

Abstract. The Canadian Network for the Detection of Atmospheric Change (CANDAC) Rayleigh–Mie–Raman lidar (CRL) at Eureka, Nunavut, has measured tropospheric clouds, aerosols, and water vapour since 2007. In remote and meteorologically significant locations, such as the Canadian High Arctic, the ability to add new measurement capability to an existing well-tested facility is extremely valuable. In 2010, linear depolarization 532 nm measurement hardware was installed in the lidar's receiver. To minimize disruption in the existing lidar channels and to preserve their existing characterization so far as is possible, the depolarization hardware was placed near the end of the receiver cascade. The upstream optics already in place were not optimized for preserving the polarization of received light. Calibrations and Mueller matrix calculations are used to determine and mitigate the contribution of these upstream optics on the depolarization measurements. The results show that with appropriate calibration, indications of cloud particle phase (ice vs. water) through the use of the depolarization parameter are now possible to a precision of ±0.05 absolute uncertainty ( ≤ 10 % relative uncertainty) within clouds at time and altitude resolutions of 5 min and 37.5 m respectively, with higher precision and higher resolution possible in select cases. The uncertainty is somewhat larger outside of clouds at the same altitude, typically with absolute uncertainty ≤ 0.1. Monitoring changes in Arctic cloud composition, including particle phase, is essential for an improved understanding of the changing climate locally and globally.

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OVERVIEW OF AIRCREW EXPOSURE TO COSMIC RADIATION IN THE CZECH REPUBLIC

Radiation Protection Dosimetry ◽

10.1093/rpd/ncz204 ◽

2019 ◽

Vol 186 (2-3) ◽

pp. 211-214

Author(s):

Ján Kubančák ◽

Dagmar Kyselová ◽

Ivan Kovář ◽

Magdaléna Hlaváčová ◽

Ronald Langer ◽

...

Keyword(s):

Czech Republic ◽

Effective Dose ◽

Cosmic Radiation ◽

Computer Code ◽

Crew Member ◽

Relative Uncertainty ◽

The Czech Republic ◽

Effective Doses ◽

The Individual

Abstract Monitoring of exposures of aircrew members of airline operators registered in the Czech Republic has been performed since 1998. The individual effective doses are calculated using the computer code CARI annually. The calculations are based on information about participation of aircrew members on the specific flights and on the parameters describing the typical flight profiles of the flights; the latter is regularly verified with control measurements performed onboard aircraft. The results show that (1) the average annual effective doses in the period from 1998 to 2017 range from 1.3 to 2.1 mSv, (2) the maximum effective dose of a crew member is 5.7 mSv and (3) the annual collective effective doses range from 1.3 to 4.1 manSv. Combined relative uncertainty of the results is ~25%.

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A High-Resolution Radiocarbon Calibration Between 11,700 and 12,400 Calendar Years Bp Derived from 230Th Ages of Corals from Espiritu Santo Island, Vanuatu

Radiocarbon ◽

10.1017/s0033822200019147 ◽

1998 ◽

Vol 40 (3) ◽

pp. 1093-1105 ◽

Cited By ~ 67

Author(s):

G. S. Burr ◽

J. Warren Beck ◽

F. W. Taylor ◽

Jacques Récy ◽

R. Lawrence Edwards ◽

...

Keyword(s):

High Resolution ◽

Younger Dryas ◽

Climatic Changes ◽

Relative Uncertainty ◽

Scale Growth ◽

Data Set ◽

Surface Ocean ◽

Growth Bands ◽

Radiocarbon Calibration ◽

Good Agreement

This paper presents radiocarbon results from a single Diploastrea heliopora coral from Vanuatu that lived during the Younger Dryas climatic episode, between ca. 11,700 and 12,400 calendar yr bp. The specimen has been independently dated with multiple 230Th measurements to permit calibration of the 14C time scale. Growth bands in the coral were used to identify individual years of growth. 14C measurements were made on each year. These values were averaged to achieve decadal resolution for the 14C calibration. The relative uncertainty of the decadal 14C data was below 1% (2σ). The data are in good agreement with the existing dendrochronology and allow for high-resolution calibration for most years. Variations in the fine structure of the 14C time series preserved in this specimen demonstrate sporadic rapid increases in the Δ14C content of the surface ocean and atmosphere. Certain sharp rises in Δ14C are coincident with gaps in coral growth evidenced by several hiatuses. These may be related to rapid climatic changes that occurred during the Younger Dryas. This is the first coral calibration with decadal resolution and the only such data set to extend beyond the dendrochronology-based 14C calibration.

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On Aethalometer measurement uncertainties and an instrument correction factor for the Arctic

Atmospheric Measurement Techniques ◽

10.5194/amt-10-5039-2017 ◽

2017 ◽

Vol 10 (12) ◽

pp. 5039-5062 ◽

Cited By ~ 21

Author(s):

John Backman ◽

Lauren Schmeisser ◽

Aki Virkkula ◽

John A. Ogren ◽

Eija Asmi ◽

...

Keyword(s):

Detection Limit ◽

Temporal Resolution ◽

Correction Factor ◽

Light Absorption ◽

The Arctic ◽

Electronic Noise ◽

Relative Uncertainty ◽

Post Processing ◽

Absorption Coefficients ◽

Additional Advantage

Abstract. Several types of filter-based instruments are used to estimate aerosol light absorption coefficients. Two significant results are presented based on Aethalometer measurements at six Arctic stations from 2012 to 2014. First, an alternative method of post-processing the Aethalometer data is presented, which reduces measurement noise and lowers the detection limit of the instrument more effectively than boxcar averaging. The biggest benefit of this approach can be achieved if instrument drift is minimised. Moreover, by using an attenuation threshold criterion for data post-processing, the relative uncertainty from the electronic noise of the instrument is kept constant. This approach results in a time series with a variable collection time (Δt) but with a constant relative uncertainty with regard to electronic noise in the instrument. An additional advantage of this method is that the detection limit of the instrument will be lowered at small aerosol concentrations at the expense of temporal resolution, whereas there is little to no loss in temporal resolution at high aerosol concentrations ( >  2.1–6.7 Mm−1 as measured by the Aethalometers). At high aerosol concentrations, minimising the detection limit of the instrument is less critical. Additionally, utilising co-located filter-based absorption photometers, a correction factor is presented for the Arctic that can be used in Aethalometer corrections available in literature. The correction factor of 3.45 was calculated for low-elevation Arctic stations. This correction factor harmonises Aethalometer attenuation coefficients with light absorption coefficients as measured by the co-located light absorption photometers. Using one correction factor for Arctic Aethalometers has the advantage that measurements between stations become more inter-comparable.

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Measuring GBAR with emulsion detector

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194514602683 ◽

2014 ◽

Vol 30 ◽

pp. 1460268 ◽

Cited By ~ 1

Author(s):

T. Ariga ◽

S. Aghion ◽

O. Ahlén ◽

C. Amsler ◽

A. Ariga ◽

...

Keyword(s):

Free Fall ◽

Gravitational Acceleration ◽

Relative Uncertainty ◽

Position Resolution ◽

Actual Experiment ◽

Universality Of Free Fall

The motivation of the AEgIS experiment is to test the universality of free fall with antimatter. The goal is to reach a relative uncertainty of 1% for the measurement of the earth's gravitational acceleration [Formula: see text] on an antihydrogen beam. High vertex position resolution is required for a position detector. An emulsion based detector can measure the annihilation vertex of antihydrogen atoms with a resolution of 1-2 μm, which if realized in the actual experiment will enable a 1% measurement of [Formula: see text] with less than 1000 [Formula: see text] atoms. Developments and achievements on emulsion detectors for the AEgIS experiment are presented here.

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