Including Calibration Error Research Articles

FLUID-LABVIR, an immersive online platform as complement to enhance the student’s learning experience in experimental laboratories of Fluid Mechanics and Fluid Engineering

Practice in experimental laboratories is a fundamental activity in the Degrees in Science and Engineering. FLUID-LABVIR platform is an attempt to innovate in the experience of students who must carry out laboratory practices, particularly in engineering and fluid mechanics subjects, by providing them with a tool (guide prepared as a website) adapted to the context of current media in a multi-platform web format (PC, mobile, tablet). This guide not only includes the theoretical foundations and the measurements which must be taken during the practice, but also includes images, animations, and explanatory videos of the handling of the practice made by teachers to support the theoretical content. It is also an additional tool to practice the handling of the experimental installation through an immersive simulator that reproduces the operation of the practice as faithfully as possible, including calibration errors of measuring equipment during the practice, saturation of indicator elements, etc. On this website, students have the possibility of downloading or accessing the practice simulator via the MyApps platform, so that they can work virtually with the demonstrative equipment, following the steps and taking the measurements that they would take in person in the laboratory. This simulator is accompanied by a short video tutorial showing how to use the simulator and how it would be operated to reproduce the handling and taking of measurements in the experimental practice. The virtual laboratory activity was implemented during the 2020/21 academic year, through three practices/simulators: Head Loss in Pipes (FM-HLP), Flow in Open Channel (FM-OC), and Wind Tunnel (FM-WT). The students considered the activity as a good complement to the practical learning before using it in the laboratory, indicating that the script seemed more attractive to them than the previous methodology based on written manuals of each practice in the laboratory. The theory and practice are also presented in more depth on the website. The students highlighted that, although it is always preferable to carry out the experimental practice in person, the immersive simulator seemed to them to be a good substitute, and the website was accessible and easy to use. The simulator reproduced the handling (stages, devices, etc.) of the experimental installation in a very acceptable way, and in some cases, they used the simulator to obtain additional data to prepare the final report of the practices. As a result of this work and this experience, the virtual laboratory activity will be offered as a complement to the traditional syllabus in the labs for subsequent academic years.

Development of monolithic SOI pixel sensors capable of fine measurements of space and time

Silicon-on-insulator (SOI) for fine measurement of space and time (SOFIST) is designed taking full advantage of advanced SOI monolithic pixel detector fabrication technology to record the charge and time information of hit pixels. The aim is to achieve 3 μm position resolution and ultimately identify the International Linear Collider beam bunches of 554 ns separation. SOFIST Ver. 3 includes full circuits to read out the charge and time for each pixel of size 30×30μm. Its performance is evaluated using a 120 GeV proton beam. The time resolution is evaluated to be 1.92 μs (including calibration error), with an intrinsic time resolution of 1.34–1.55 μs. Additionally, multi-memory readout functionality is successfully examined. With SOFIST Ver. 4, the same functionality is to be realized with a 20×20μm pixel size by 3D stacking. The first chip was successfully tested to image β rays. The connection yield of Au micro-bumps is greater than 99.9%.

Have You Tested Your Goldmann Tonometer Today?

Intraocular pressure (IOP) is the only known modifiable risk factor for glaucoma. Besides being a cornerstone in glaucoma management, accurate measurement of IOP forms an important component of routine ophthalmic evaluation. Despite the innovation of various newer tonometers, Goldmann applanation tonometer is still considered the Gold standard for IOP measurement. However, there are several reported sources of error including calibration error.1 Errors in calibration of Goldmann applanation tonometer are often overlooked in clinical practice. Kumar and Jivan2 conducted a questionnaire survey of 100 ophthalmology residents from UK. 85% of respondents to their questionnaire never checked tonometers for errors.2 Wessels and Oh3 did a field survey of 94 ophthalmologists’ offices to assess the accuracy of tonometers in daily use. Less than 15% of ophthalmologists in their study knew how to perform calibration error testing.3 Given the importance of applanation tonometry in glaucoma management and the ease of calibration error testing, these figures are surprising.

Observations of the cosmic microwave background and galactic foregrounds at 12-17-GHz with the COSMOSOMAS experiment

We present the analysis of the first 18 months of data obtained with the COSMOSOMAS (COSMOlogical Structures On Medium Angular Scales) experiment at the Teide Observatory (Tenerife). Three maps have been obtained at 12.7, 14.7 and 16.3-GHz covering 9000-deg2 each with a resolution of ∼1° and with sensitivities 49, 59 and 115-μK-beam−1, respectively. These data in conjunction with the Wilkinson Microwave Anisotropy Probe (WMAP) first year maps have revealed that the cosmic microwave background (CMB) is the dominant astronomical signal at high galactic latitude (|b| > 40°) in the three COSMOSOMAS channels with an average amplitude of 29.7 ± 1.0-μK (68 per cent c.l. not including calibration errors). This value is in agreement with the predicted CMB signal in the COSMOSOMAS maps using the best-fitting Λ-CDM model to the WMAP power spectrum. Cross-correlation analysis of the 408-MHz map and the COSMOSOMAS data at high galactic latitudes give values in the range 17.0–14.4-μK from 12.7 to 16.3-GHz. Removing detected point sources in this template, reduces the amplitude of the correlated signal to 8–9-μK. The mean spectral index of the correlated signal between the 408-MHz desourced and the COSMOSOMAS maps is between −3.20 and −2.94 at |b| > 40° which indicates that this signal is due to synchrotron emission. Cross-correlation of COSMOSOMAS data with the Diffuse Infrared Background Experiment (DIRBE) map at 100-μm shows the existence of a common signal with amplitude 7.4 ± 1.1, 7.5 ± 1.1 and 6.5 ± 2.3-μK in the 12.7, 14.7 and 16.3-GHz COSMOSOMAS maps at |b| > 30°. Using the WMAP data, we find this DIRBE correlated signal rises from high to low frequencies flattening below ∼20-GHz. At higher galactic latitudes the average amplitude of the correlated signal with the DIRBE maps decreases slightly. The frequency behaviour of the COSMOSOMAS/WMAP correlated signal with DIRBE is not compatible with the expected tendency for thermal dust. A study of the Hα emission maps do not support free–free as a major contributor to that signal. Our results provide new evidence of a Galactic foreground with properties compatible with predictions by spinning dust models.

Quantitative gas chromatography–olfactometry. Analytical characteristics of a panel of judges using a simple quantitative scale as gas chromatography detector

Some questions related to the ability of gas chromatography–olfactometry (GC–O) to provide quantitative measurements of the concentration of a given odorant in an extract are explored and discussed. A panel of eight individuals has been used to evaluate the intensity of 15 odorants present at different concentrations. The use of very simple scales, such as a 0–3 scale, makes it possible to build calibration graphs based on the different stimulus–response models (Fechner, Stevens, Hill) and, with a proper calibration, up to nine different concentration levels can be discriminated by an eight-judge panel. The signal shows a good long-term stability, and its precision varies between 3.7 and 8% of the whole scale, with 5.7% as average. Sensitivity is extremely dependent on the compound: in the best case a concentration change of 20% can be detected, while in the worst, concentrations must differ more than one order of magnitude. In average, concentrations must differ between 2 and 4.7 times (including calibration error) or between 1.2 and 2.3 (excluding calibration error). The performance of the different judges, the effect of the close elution of two odors and the benefits derived from the use of more complex scales (7-points) are briefly discussed from the perspective of the analytical performance of GC–O methods.

Observations of the bright radio sources in the North Celestial Pole region at the RATAN-600 radio telescope

A survey of the North Celestial Pole region using the RATAN-600 radio telescope at five frequencies in the range 2.3 to 21.7 GHz is described. Sources were chosen from the NVSS catalogue. The flux densities of 171 sources in the Declination range +75 to +88 are presented; typical flux density errors are 5-10 percent including calibration errors. About 20 percent of the sources have flat spectra or a flat component.

Detection of Cosmic Microwave Background Anisotropy by the Third Flight of the Medium-Scale Anisotropy Measurement

The third flight of the Medium-Scale Anisotropy Measurement (MSAM1), in 1995 June, observed a new strip of sky, doubling the sky coverage of the original MSAM1 data set. MSAM1 observes with a 05 beam size in four bands from 5 to 20 cm-1. From these four bands we derive measurements of cosmic microwave background radiation (CMBR) anisotropy and interstellar dust emission. Our measurement of dust emission correlates well with the 100 μm IRAS Sky Survey Atlas; from this comparison we determine an effective emissivity spectral index between 100 μm and 444 μm of 1.46±0.28. Analysis of our measurement of CMBR anisotropy shows that for Gaussian-shaped correlation functions with θc = 03, we place a limit on total rms anisotropy of 2.2×10−5<ΔT/T<3.9×10−5 (90% confidence interval, including calibration error). The band-power limits are ⟨δT⟩ ≡ ⟨l(l+1)Cl/2π⟩½=50+16−11 μK at l=160, and ⟨δT⟩=65+18−13 μK at l=270 (1 σ limits, including calibration error). The corresponding limits with statistical errors only are ⟨δT⟩=50+ 13−9 μK and ⟨δT⟩=65+ 14−10 μK, respectively. These measurements are consistent with a standard adiabatic cold dark matter model; we discuss constraints on h, n, and the redshift of reionization.

β-γ-zirkularpolarisations-korrelation des Sc 46 und chemische form der quelle

The β-γ circular-polarization correlation of Sc 46 has been measured by means of forward Compton scattering. Solid scandium sources of the following compounds were investigated: oxide, chloride, nitrate, sulfate, metal and ammoniumfluoscandiate. Furthermore, a number of thin liquid sources were measured: chloride in diluted hydrochloric acid, acetylacetonate in m-xylene, and acetylacetonate in methylene bromide. A liquid mixed source of Co 60 and Sc 46 was also measured. A total of 15 sources were investigated. The results of the individual sources are, within statistics, all in agreement with each other, and in the same way with the earlier Heidelberg and Livermore results. The observed correlations turned out to be, within statistics, completely independent of the age of the source. The anisotropy parameter A of the β-γ circular-polarization correlation, averaged over all sources, was found to be A = 0.113±0.008 (standard deviation, including calibration error), which implies a ratio X between Fermi and Gamow-Teller contributions of X = −0.040±0.011. In supplementary runs, the β-γ directional correlation as well as the γ-γ directional correlation were measured, the latter with chloride and sulfate sources. The β-γ directional correlation was found to be isotropic while the γ-γ correlation was found to have the anisotropy expected for a non-attenuated E2 cascade. In appendices the problems of estimating source thickness effects on the measured angular distribution of electrons from oriented nuclei, on the measured β-γ circular-polarization correlation, and on the measured β-gg directional correlation are treated, as well as the problem of measuring random coincidences in a fast-slow coincidence circuit.