MetrologiaPub Date : 2024-01-01DOI: 10.1088/0026-1394/61/1a/08008
Joële Viallon, Faraz Idrees, Philippe Moussay, Robert Wielgosz, Fuuming Kai, Lemuel Joel Kuehsamy, Yuxi Cui, James E Norris, Joseph Hodges
{"title":"Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with NMC-A*STAR, July 2022","authors":"Joële Viallon, Faraz Idrees, Philippe Moussay, Robert Wielgosz, Fuuming Kai, Lemuel Joel Kuehsamy, Yuxi Cui, James E Norris, Joseph Hodges","doi":"10.1088/0026-1394/61/1a/08008","DOIUrl":"https://doi.org/10.1088/0026-1394/61/1a/08008","url":null,"abstract":"<title>Main text</title>As part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of Singapore maintained by the National Metrology Centre, A*STAR (NMC, A*STAR) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM), via a transfer standard maintained by the National Institute of Standards and Technology (NIST). The instruments have been compared over a nominal ozone amount-of-substance fraction range of 0 nmol/mol to 500 nmol/mol.To reach the main text of this paper, click on <ext-link xlink:href=\"https://www.bipm.org/documents/d/guest/bipm-qm-k1_a-star_2022\" xlink:type=\"simple\">Final Report</ext-link>. Note that this text is that which appears in Appendix B of the BIPM key comparison database <ext-link xlink:href=\"https://www.bipm.org/kcdb/\" xlink:type=\"simple\">https://www.bipm.org/kcdb/</ext-link>.The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":"17 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140613171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MetrologiaPub Date : 2024-01-01DOI: 10.1088/1681-7575/ad844b
Brian J Simonds, Kyle A Rogers, Sven Schulze, David Newell, Gordon Shaw, Johannes Wahl, Paul A Williams, John H Lehman
{"title":"Practical realization of the watt from Planck's constant using radiation pressure.","authors":"Brian J Simonds, Kyle A Rogers, Sven Schulze, David Newell, Gordon Shaw, Johannes Wahl, Paul A Williams, John H Lehman","doi":"10.1088/1681-7575/ad844b","DOIUrl":"10.1088/1681-7575/ad844b","url":null,"abstract":"<p><p>A primary force standard is implemented to realize the watt through Planck's constant by means of radiation pressure at the kilowatt level. The high amplification laser-pressure optic, or HALO, is a multiple reflection radiation pressure apparatus used for absolute radiometry of high-power lasers. In this work, a primary standard electrostatic force balance is used to measure the reflection-enhanced optical forces. With this configuration, the HALO is used to measure laser powers in the range of 100 W-5000 W from a 1070 nm fiber laser. The expanded uncertainty of the 5 kW measurement is 0.12%, which is both the lowest uncertainty multi-kW measurement and radiation pressure-based measurement to-date. The HALO result was validated against a thermal primary standard using a calibrated transfer standard at 2 kW. The degree of equivalence was 0.78% ± 1.12%, which demonstrates agreement within the uncertainties of these two primary standards.</p>","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":"61 6","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11938377/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MetrologiaPub Date : 2024-01-01DOI: 10.1088/1681-7575/ad8927
Patrick F Egan
{"title":"Wavemeter calibration by frequency comb.","authors":"Patrick F Egan","doi":"10.1088/1681-7575/ad8927","DOIUrl":"10.1088/1681-7575/ad8927","url":null,"abstract":"<p><p>Upgrades to the vacuum wavelength calibration service at the National Institute of Standards and Technology are reported. The instrumentation centerpiece is an optical frequency comb stabilized to a GPS-disciplined oscillator, thereby providing direct traceability to the SI second. Historically, the service has covered lasers at the popular interferometry wavelengths red and green. Recently, capability has been added for calibrating wavemeters at multiple telecom wavelengths in the range (1520 < <i>λ</i> < 1570) nm. For most commercially available wavemeters, the test uncertainty ratio is about 10<sup>4</sup>.</p>","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":"61 6","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11729613/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142984250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MetrologiaPub Date : 2023-12-28DOI: 10.1088/1681-7575/ad1692
Andrea Prato, Francesca Pennecchi, Gianfranco Genta, Alessandro Schiavi
{"title":"A Bayesian statistical method for large-scale MEMS-based sensors calibration: a case study on 100 digital accelerometers","authors":"Andrea Prato, Francesca Pennecchi, Gianfranco Genta, Alessandro Schiavi","doi":"10.1088/1681-7575/ad1692","DOIUrl":"https://doi.org/10.1088/1681-7575/ad1692","url":null,"abstract":"Low-cost sensors and in particular micro-electro-mechanical systems (MEMS) devices are widely used in many applications, including consumer electronics, healthcare, automotive, and industrial automation. Their large-scale production (typically in the order of millions per week in a single factory) would require the calibration of a huge number of devices that would be costly and time-consuming. A solution can be found in the use of statistical methods in order to (at least partially) substitute for the typical calibration procedures. In this work, we propose a Bayesian method to statistically calibrate large batches of sensors using probabilistic models and prior knowledge. The method involves experimentally calibrating only a small sample of sensors, then infer the number of reliable sensors in the entire batch and assign an appropriate uncertainty to all the sensors. Therefore, it can be considered as a statistical calibration of the batch. The Bayesian nature of this approach allows reducing the number of experimental calibrations by incorporating the prior knowledge coming from the previous calibration of a ‘benchmark’ batch, which is performed ‘once and for all’ and is representative of the whole production process. The application and validation of the method are performed through the calibration of 100 digital MEMS accelerometers. Validation results showed an acceptable agreement between experimental-based bootstrap and theoretical values, with relative differences within ±7%.","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":"18 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139095855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MetrologiaPub Date : 2023-12-11DOI: 10.1088/1681-7575/ad141b
Richard J. C. Brown
{"title":"On the distinction between SI base units and SI derived units","authors":"Richard J. C. Brown","doi":"10.1088/1681-7575/ad141b","DOIUrl":"https://doi.org/10.1088/1681-7575/ad141b","url":null,"abstract":"This letter discusses the criteria that should be considered when deciding whether or not the distinction between base units and derived units in the International System of Units (SI) is useful, a debate that has been reignited following the 2019 revision of the SI. It is proposed that the correct question to ask is whether the concept of independent quantities, and the dimensional analysis it allows, remains useful—since that is the ultimate origin of the distinction between SI base units and SI derived units. Furthermore, the letter explains that this distinction is not related to whether the defining constants used in the revised SI after 2019 are any more fundamental than they were previously, nor whether the links between defining constants and SI base units are any less direct than they were prior to 2019. Finally, an opinion is offered that the concept of quantity dimensions and dimensional analysis remains useful, and certainly does no harm.","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":"9 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138979395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MetrologiaPub Date : 2023-12-07DOI: 10.1088/1681-7575/ad10bd
Mariusz Dzwonkowski, Vorya Waladi, Adrian Bekasiewicz
{"title":"Multi-taper-based automatic correction of non-anechoic antenna measurements","authors":"Mariusz Dzwonkowski, Vorya Waladi, Adrian Bekasiewicz","doi":"10.1088/1681-7575/ad10bd","DOIUrl":"https://doi.org/10.1088/1681-7575/ad10bd","url":null,"abstract":"Prototype measurements belong to the key steps in the development of antenna structures. Although accurate validation of their far-field performance can be realized in dedicated facilities, such as anechoic chambers, the high cost of their construction and maintenance might not be justified if the main goal of measurements is to support teaching or low-budget research. Instead, they can be performed in non-anechoic conditions and then refined using appropriate correction algorithms. Unfortunately, the existing post-processing methods suffer from multiple challenges that include manual setup of parameters as well as validation of performance in idealized conditions. In this communication, a multi-taper-based framework for correction of antenna characteristics obtained in non-anechoic environments has been proposed. The algorithm augments one-shot measurements of the structure under test in order to extract the line-of-sight responses while attenuating the interferences pertinent to multi-path propagation and noise from external sources of radiation. The performance of the proposed correction routine has been demonstrated in two test sites using a geometrically small Vivaldi radiator and validated against state-of-the-art techniques from the literature. The uncertainty budget for the measurements performed using the approach amounts to 0.26 dB, which is low given challenging propagation conditions considered for experiments.","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":"2 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138680425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Characterization of laser-pumped Cs-4He atomic magnetometer","authors":"Hao Liu, Jia Kong, Jiqing Fu, Shuirui Yang, Xiaoming Lu, Xiaoguang Wang","doi":"10.1088/1681-7575/ad1339","DOIUrl":"https://doi.org/10.1088/1681-7575/ad1339","url":null,"abstract":"\u0000 In principle, laser-pumped Cs-4He magnetometers can take advantage of the high sensitivity of optically pumped magnetometers and the high accuracy of proton magnetometers. However, insufficient experimental studies have been conducted on the optimization conditions and physics of this type of magnetometer. In this study, we investigate the experimental performance of a laser-pumped Cs-4He magnetometer by optimizing the sensitivity of the excitation pulse settings. We report some dependence relationships that have not been previously reported. The optimal settings under the obtainable experimental conditions in our lab are 34 ℃ for temperature, 10 μs for pulse duration, and 67 V and 2.2 V for high- and low-level voltages, respectively, which provide a sensitivity of 26 pT/√Hz within a frequency of 0.08-0.2 Hz. This study provides a solid reference for further improving the Cs-4He magnetometer, offers the possibility of measuring physical constants more accurately, and provides a deeper understanding of plasma interaction processes.","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":"10 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138591864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MetrologiaPub Date : 2023-11-23DOI: 10.1088/0026-1394/60/1a/08030
Ruben P Ziel, E Zalewska, Adriaan M H van der Veen, Heinrich Kipphardt, Dirk Tuma, Andres Rojo Esteban, Teresa E Fernández Vicente, Tatiana Macé, Christophe Sutour, Fabrice Marioni, Judit Fükő, László Szűcs, Tamás Büki, Zsófia Nagyné Szilágyi, Dariusz Cieciora, Grzegorz Ochman, Przemysław Romanowski, Anna Lis, Magdalena Garnuszek, Miroslava Valkova, Andreas Ackermann, Celine Pascale, Bernhard Niederhauser, Tanıl Tarhan, Aylin Boztepe, Jan Beránek, Miroslav Bárta
{"title":"International comparison EURAMET.QM-K3.2019 - automotive exhaust gases","authors":"Ruben P Ziel, E Zalewska, Adriaan M H van der Veen, Heinrich Kipphardt, Dirk Tuma, Andres Rojo Esteban, Teresa E Fernández Vicente, Tatiana Macé, Christophe Sutour, Fabrice Marioni, Judit Fükő, László Szűcs, Tamás Büki, Zsófia Nagyné Szilágyi, Dariusz Cieciora, Grzegorz Ochman, Przemysław Romanowski, Anna Lis, Magdalena Garnuszek, Miroslava Valkova, Andreas Ackermann, Celine Pascale, Bernhard Niederhauser, Tanıl Tarhan, Aylin Boztepe, Jan Beránek, Miroslav Bárta","doi":"10.1088/0026-1394/60/1a/08030","DOIUrl":"https://doi.org/10.1088/0026-1394/60/1a/08030","url":null,"abstract":"<title>Main text</title>EURAMET.QM-K3.2019 was a repeat of the key comparison EURAMET.QM-K3 on the composition of automotive exhaust gases. New in EURAMET.QM-K3.2019 was the addition of the amount fraction oxygen to the programme. The key comparison reference values were obtained independently, using static gravimetry and appropriate corrections from purity analysis and are linked to those of CCQM-K3.2019. The key comparison results show equivalence between the measurement standards maintained by the participating national metrology institutes. The demonstrated equivalence can be used to underpin services related to automotive exhaust gases as well as generically through the flexible scheme (\"track A\")To reach the main text of this paper, click on <ext-link xlink:href=\"https://www.bipm.org/documents/d/guest/euramet-qm-k3-2019\" xlink:type=\"simple\">Final Report</ext-link>. Note that this text is that which appears in Appendix B of the BIPM key comparison database <ext-link xlink:href=\"https://www.bipm.org/kcdb/\" xlink:type=\"simple\">https://www.bipm.org/kcdb/</ext-link>.The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":"86 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138680287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MetrologiaPub Date : 2023-11-23DOI: 10.1088/0026-1394/60/1a/01013
Kwang Min Yu, Wan Seop Kim
{"title":"Final report on APMP.EM-K2 key comparison of resistance standards at 10 MΩ and 1 GΩ","authors":"Kwang Min Yu, Wan Seop Kim","doi":"10.1088/0026-1394/60/1a/01013","DOIUrl":"https://doi.org/10.1088/0026-1394/60/1a/01013","url":null,"abstract":"<title>Main text</title>In order to link the National Metrology Institutes (NMI) organized in Asia Pacific Metrology Programme (APMP) to the key comparison CCEM-K2, APMP.EM-K2 key comparison was piloted by the Korea Research Institute of Standards and Science (KRISS), beginning in July 2010 and completed July 2014 with the participation of 13 National Metrology Institutes (NMIs). The results of this key comparison for 10 MΩ and 1 GΩ standards indicate good agreement among the 13 participating NMIs despite the long comparison period. Agreement is well within the level of confidence of 95%.To reach the main text of this paper, click on <ext-link xlink:href=\"https://www.bipm.org/documents/d/guest/apmp-em-k2\" xlink:type=\"simple\">Final Report</ext-link>. Note that this text is that which appears in Appendix B of the BIPM key comparison database <ext-link xlink:href=\"https://www.bipm.org/kcdb/\" xlink:type=\"simple\">https://www.bipm.org/kcdb/</ext-link>.The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":"146 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138680376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MetrologiaPub Date : 2023-11-23DOI: 10.1088/0026-1394/60/1a/06024
Romain Coulon, Carine Michotte, Sammy Courte, Manuel Nonis, Milton W Van Rooy, Joline Lubbe, Martin J van Staden
{"title":"Update of the BIPM comparison BIPM.RI(II)-K1.Na-22 of activity measurements of the radionuclide 22Na to include the 2022 result of the NMISA (South Africa)","authors":"Romain Coulon, Carine Michotte, Sammy Courte, Manuel Nonis, Milton W Van Rooy, Joline Lubbe, Martin J van Staden","doi":"10.1088/0026-1394/60/1a/06024","DOIUrl":"https://doi.org/10.1088/0026-1394/60/1a/06024","url":null,"abstract":"<title>Main text</title>Since 1976, 13 laboratories have submitted 30 samples of <sup>22</sup>Na to the International Reference System (SIR) for activity comparison at the Bureau International des Poids et Mesures (BIPM), with comparison identifier BIPM.RI(II)-K1.Na-22. Recently, the NMISA (South Africa) participated in the comparison and the key comparison reference value (KCRV) has been updated. The degrees of equivalence between each equivalent activity measured in the SIR and the updated KCRV have been calculated and the results are given in the form of a table. A graphical representation is also given.To reach the main text of this paper, click on <ext-link xlink:href=\"https://www.bipm.org/documents/d/guest/bipm-ri-ii-k1-na-22-nmisa_2022\" xlink:type=\"simple\">Final Report</ext-link>. Note that this text is that which appears in Appendix B of the BIPM key comparison database <ext-link xlink:href=\"https://www.bipm.org/kcdb/\" xlink:type=\"simple\">https://www.bipm.org/kcdb/</ext-link>.The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).","PeriodicalId":18444,"journal":{"name":"Metrologia","volume":"5 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138680279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}