Real-time monitoring of the rubber belt tension in an industrial conveyor

The paper presents a novel system for monitoring of the work of industrial belt conveyor. It is based on the strain gauges placed directly on the roller surface that measure pressing force of the belt on the roller. Automatical operation of the measurement system minimizes impact of an operator on the measurement results. Experimental researches included the stability of indications during 5 days, Type A uncertainty estimation and equipment variation EV calculations. Expanded uncertainty calculated for the level of confidence 95% was below 0.1% of the actually measured value, and percentage repeatability %EV = 9.5% was obtained. It can be considered satisfactory, since usually it is required %EV < 10% for new measurement systems.

Real-time monitoring of the rubber belt tension in an industrial conveyor

The paper presents a novel system for monitoring of the work of industrial belt conveyor. It is based on the strain gauges placed directly on the roller surface that measure pressing force of the belt on the roller. Automatical operation of the measurement system minimizes impact of an operator on the measurement results. Experimental researches included the stability of indications during 5 days, Type A uncertainty estimation and equipment variation EV calculations. Expanded uncertainty calculated for the level of confidence 95% was below 0.1% of the actually measured value, and percentage repeatability %EV = 9.5% was obtained. It can be considered satisfactory, since usually it is required %EV < 10% for new measurement systems.

Spectral irradiance scale realization and uncertainty analysis based on a 14 mm diameter WC-C fixed point blackbody from 250 nm to 2500 nm

Spectral irradiance scale in the wavelength range from 250 nm to 2500 nm was realized at National Institute of Metrology (NIM) on the basis of a large area tungsten carbide–carbon (WC-C) high temperature fixed point blackbody, which is composed of a 14 mm diameter WC-C fixed point cell and a variable temperature blackbody BB3500MP as a furnace. A series of 1000 W FEL tungsten halogen lamps were used as transfer standards. The new spectral irradiance scale was compared with the scale based on a variable-temperature blackbody BB3500M, and the divergence between these two methods varied from -0.66% to 0.79% from 280 nm to 2100 nm. The measurement uncertainty of spectral irradiance scale based on fixed-point blackbody was analyzed, and the expanded uncertainty was estimated as 3.9% at 250 nm, 1.4% at 280 nm, 0.43 % at 400 nm, 0.27% at 800 nm, 0.25% at 1000 nm, 0.62% at 1500 nm, 0.76% at 2000 nm, and 2.4% at 2500 nm respectively. In the range from 300 nm to 1000 nm the fixed-point scale was improved obviously: the uncertainty decreased by more than 25% compared to the uncertainty based on the variable temperature blackbody. Below 300 nm, the uncertainty became higher because the signal to noise ratio was poor. Above 1100 nm, the contribution of temperature measurement to the uncertainty of spectral irradiance decreases, therefore the uncertainties of two methods are almost at the same level. The fixed-point blackbody was also used to realize the correlated colour temperature and distribution temperature of a tungsten filament lamp, the deviation from the variable temperature blackbody method was -0.5 K and -2.9 K, respectively.

Optical power scale realization using the predictable quantum efficient detector

We report realization of scales for optical power of lasers and spectral responsivity of laser power detectors based on a predictable quantum efficient detector (PQED) over the spectral range of 400 nm–800 nm. The PQED is characterized and used to measure optical power of a laser that is further used in calibration of the responsivities of a working standard trap detector at four distinct laser lines, with an expanded uncertainty of about 0.05%. We present a comparison of responsivities calibrated against the PQED at Aalto and the cryogenic radiometer at RISE, Sweden. The measurement results support the concept that the PQED can be used as a primary standard of optical power.

PAWG Pilot Study on Quantification of SARS-CoV-2 Monoclonal Antibody - Part 1

Main text Under the auspices of the Protein Analysis Working Group (PAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a pilot study, CCQM-P216, was coordinated by the Chinese National Institute of Metrology (NIM), National Research Council of Canada (NRC) and the Bureau International des Poids et Mesures (BIPM). Eleven Metrology Institutes or Designated Institutes and the BIPM participated in the first phase of the pilot study (Part 1). The purpose of this pilot study was to develop measurement capabilities for larger proteins using a recombinant humanized IgG monoclonal antibody against Spike glycoprotein of SARS-CoV-2 (Anti-S IgG mAb) in solution. The first phase of the study was designed to employ established methods that had been previously studies by the CCQM Protein Analysis Working Group, involving the digestion of protein down to the peptide or amino acid level. The global coronavirus pandemic has also led to increased focus on antibody quantitation methods. IgG are among the immunoglobulins produced by the immune system to provide protection against SARS-CoV-2. Anti-SARS-CoV-2 IgG can therefore be detected in samples from affected patients. Antibody tests can show whether a person has been exposed to the SARS-CoV-2, and whether or not they potentially show lasting immunity to the disease. With the constant spread of the virus and the high pressure of re-opening economies, antibody testing plays a critical role in the fight against COVID-19 by helping healthcare professionals to identify individuals who have developed an immune response, either via vaccination or exposure to the virus. Many countries have launched large-scale antibody testing for COVID-19. The development of measurement standards for the antibody detection of SARS-CoV-2 is critically important to deal with the challenges of the COVID-19 pandemic. In this study, the SARS-CoV-2 monoclonal antibody is being used as a model system to build capacity in methods that can be used in antibody quantification. Amino acid reference values with corresponding expanded uncertainty of 36.10 ± 1.55 mg/kg, 38.75 ± 1.45 mg/kg, 18.46 ± 0.78 mg/kg, 16.20 ± 0.67 mg/kg and 30.61 ± 1.30 mg/kg have been established for leucine, valine, phenylalanine, isoleucine and proline, respectively. Agreement between nearly all laboratories was achieved for the amino acid analysis within 2 to 2.5 %, with one participant achieving markedly higher results due to a technical issue found in their procedure; this result was thus excluded from the reference value calculations. The relatively good agreement within a laboratory between different amino acids was not dissimilar to previous results for peptides or small proteins, indicating that factors such as hydrolysis conditions and calibration procedures could be the largest sources of variability. Peptide reference values with corresponding expanded uncertainty of 4.99 ± 0.28 mg/kg and 6.83 ± 0.65 mg/kg have been established for ALPAPIEK and GPSVFPLAPSSK, respectively. Not surprisingly due to prior knowledge from previous studies on peptide quantitation, agreement between laboratories for the peptide-based analysis was slightly poorer at 3 to 5 %, with one laboratory's result excluded for the peptide GPSVFPLAPSSK. Again, this level of agreement was not significantly poorer than that achieved in previous studies with smaller or less complex proteins. To reach the main text of this paper, click on Final Report.

Laboratory characterisations and intercomparison sounding test of dual thermistor radiosondes for radiation correction

A dual thermistor radiosonde (DTR) comprising two (white and black) sensors with different emissivities was developed to correct the effects of solar radiation on temperature sensors based on in-situ radiation measurements. Herein, the DTR performance is characterised in terms of the uncertainty via a series of ground-based facilities and an intercomparison sounding test. The DTR characterisation procedure using laboratory facilities is as follows: individually calibrate the temperature of the thermistors in a climate chamber; test the effect of temperature on the resistance reading using radiosonde boards in the climate chamber; individually perform radiation tests on thermistors; and perform parameterisation of the radiation measurement and correction formulas using an upper air simulator with varying temperature, pressure and ventilation speed. These results are combined and applied to the DTR sounding test conducted in July, 2021. Thereafter, the effective irradiance is measured using the temperature difference between the white and black sensors of the DTR. The measured irradiance is then used for the radiation correction of the DTR white sensor. The radiation-corrected temperature of the DTR is mostly consistent with that of a commercial radiosonde (Vaisala, RS41) within the expanded uncertainty (~0.35 ℃) of the DTR at the coverage factor k = 2. Furthermore, the components contributing to the uncertainty of the radiation measurement and correction are analysed. The DTR methodology can improve the accuracy of temperature measurement in the upper air within the framework of the traceability to the International System of Units.

Method for determining uncertainty and error in the process of ophthalmic lens calibration

In the present investigation, a scientific procedure was developed, and a mathematical model was proposed, with the objective of determining, under standard conditions, the uncertainty, and the measurement of dioptric power in ophthalmic lenses. The methodology of the scientific procedure is based on the fundamentals of geometric optics, this process guarantees and establishes a standardized uncertainty measure in repeatable and reproducible processes. The methodology is complemented with a proposed mathematical model based on the guide for the expression of uncertainty in measurement - GUM. This model can be applied to lenses used for calibrating eye care equipment (such as lensometers, which are used to diagnose myopia and farsightedness) by evaluating the lenses without having direct contact with patients. When the proposed mathematical model was applied, its experimental result was a maximum expanded uncertainty of ± 0.0079 diopters in a 0.5-diopter lens. This is optimal compared to the result of other authors this article, who reported a maximum expanded uncertainty of ± 0.0086 diopters. In conclusion, the application of this scientific procedure provides manufacturers and users of this type of lenses with a reliable measurement thanks to a calibration process based on geometrical optics and centered on patient safety.

REASSESSMENT OF UNCERTAINTY EXPANSION BY LINEAR ADDITION OF LONG-TERM COMPONENTS FROM TOP-DOWN INFORMATION

ABSTRACT Since radiocarbon accelerator mass spectrometry (14C AMS) is considered a high-precision technique, reassessment of the measurement uncertainty has been a topic of interest. Scientists from analytical and metrological fields have developed the top-down and bottom-up measurement of uncertainty approaches. The 14C quoted error should approximate the uncertainty of long-term repetitions of the top-down approach in order to be realistic. The novelty of this paper is that the uncertainty of both approaches were approximated to each other. Furthermore, we apportioned the graphitization, instrumentation, and bias components in order to additively expand the quoted error. Our results are comparable to error multipliers and to long-term repeatability studies reported by other laboratories. Our laboratory was established in late 2012 with N2 as stripper gas and 7 years later, we changed to helium stripper. Thus, we were able to compare both gases, and demonstrate that helium is a better stripper gas. In absolute F14C units, the ranges of graphitization+bias combined uncertainties were (0.7 to 4.1) × 10–3 for N2 and (0.7–3.0) × 10–3 for He depending on the standard 14C content. The error multiplier for He defined as the expanded uncertainty over quoted error, in average, was 1.7; while without the bias, the multiplier was 1.3.

Uncertainty analysis for the data-driven model using Monte Carlo simulations to predict sodium adsorption rate: A case study, Aras, Sepid-Rud, and Karun Rivers in Iran

Water quality management requires a profound understating of future variations of surface and groundwater qualities for assessment and planning for human consumption, industrial, and irrigation purposes. In this regard, mathematical models, such as Box-Jenkins time series models, Bayesian time series models, and data-driven models are available for future prediction of water quality. However, the uncertainty associated with forecasting is one of the main problems of using these models towards water quality and future planning. In the present work, the uncertainty of the Adaptive Neuro-Fuzzy Inference System, based on Fuzzy c-means clustering, (ANFIS-FCMC) (genfis 3) model is quantified to analyze and predict Sodium Adsorption Rate(SAR) of water of Aras, Sepid-Rud, and Karun Rivers by using Monte Carlo simulations. The results indicate the combined standard and the expanded uncertainty simulated for SAR of Aras River water are 0.58 and1.16, respectively, and the gap is 2 .412 ±1.1622. Also, the combined standard and the expanded uncertainty simulated for SAR of Spid-Rud River water were1.11 and 2.22, respectively, and the gap is equal to 2 .235 ±2.22. Furthermore, the combined standard and the expanded uncertainty simulated for SAR of Aras River water are 2.063, and 4.126, respectively, and the gap is 4.79 ±4.126. Finally, the minimum uncertainty happened to predict SAR of Aras River using ANFIS-FCMC (genfis3) model and maximum SAR uncertainty belong to Karun River.

Calibration system design for multi-beam sonar

A set of calibration system for multi-beam sonar is designed by the principle and method of underwater acoustic metrology. Using the multi-dimensional operation control device, the calibration for acoustical index is completed in the anechoic pool, including the sound source level and beam width. The calibration for geometrical index is carried out in the large scale and deep-water prototype pool, including the bathymetric accuracy. Components and method of the calibration system are introduced, as well as the expanded uncertainty of the calibration system is presented. By comparing the calibrating value and the indicating or nominal value of the detected multi-beam sonar, test results show that the sound source level error is less than 0.7dB, the beam width indication error is less than 10% and the bathymetry value error is less than 0.2%.