Investigation of the stability of graphene devices for quantum resistance metrology at direct and alternating current

Interlaboratory comparisons of the quantized Hall resistance are essential to verify the international coherence of primary impedance standards. Here we report on the investigation of the stability of p-doped graphene-based quantized Hall resistance devices at direct and alternating currents at CMI, KRISS, and PTB. To improve the stability of the electronic transport properties of the polymer encapsulated device, it was shipped in an over-pressurized transport chamber. The agreement of the quantized resistance with RK/2 at direct current was on the order of 1 nΩ/Ω between 3.5 T and 7.5 T at a temperature of 4.2 K despite changes in the carrier density during the shipping of the devices. At alternating current, the quantized resistance was realized in a double-shielded graphene Hall device. Preliminary measurements with digital impedance bridges demonstrate the good reproducibility of the quantized resistance near the frequency of 1 kHz within 0.1 μΩ/Ω throughout the international delivery.

Calibration of Tanks and Ships’ Tanks for Storage and Transportation of Liquids by Laser Scanning

The goal of the research is to improve the accuracy of measurement the volume and mass of oil and oil products by the stationary measuring tanks and ships’ tanks. It is possible to achieving this goal only by using the laser scanning at tanks calibration. Metrological and other technical requirements for laser scanners have been developed. It is proved by the results of mathematical modeling that only the compliance of scanners with the developed requirements makes it possible to achieve the set goal. It has been developed methods of measurements by laser scanners that allow to achieve an increase in the accuracy of determination the interval capacities of all types of the tanks. Methods, formulae and algorithms for interval capacities of tanks calculation are very complicated. Therefore, the interlaboratory comparisons for the interval capacities, calculated by laboratories own software developed for processing the results of the specified calibration are proposed. It is concluded that the developed requirements, methods and algorithms will allow, in several times, to increase the accuracy of determining the interval capacities of the tanks with a significant reduction in time for measurements and processing of their results.

Analysis of the Experience of Participation in Interlaboratory Comparisons of the Radiation Control Laboratory in National Accreditation System

Purpose: Formation of the idea of laboratories accredited by Accreditation System of Russian Federation, in particular radiation control laboratories, about the possibility of confirming technical competence by means of participation in interlaboratory comparison tests at international level. Content: Description of the experience of successful passing the international comparisons by radiation control laboratories under up-to-date requirements. Conclusion: The experience described in the article can be used by accredited laboratories in practice for conformity validation with accreditation criteria.

Benchmarking the ACEnano Toolbox for Characterisation of Nanoparticle Size and Concentration by Interlaboratory Comparisons

ACEnano is an EU-funded project which aims at developing, optimising and validating methods for the detection and characterisation of nanomaterials (NMs) in increasingly complex matrices to improve confidence in the results and support their use in regulation. Within this project, several interlaboratory comparisons (ILCs) for the determination of particle size and concentration have been organised to benchmark existing analytical methods. In this paper the results of a number of these ILCs for the characterisation of NMs are presented and discussed. The results of the analyses of pristine well-defined particles such as 60 nm Au NMs in a simple aqueous suspension showed that laboratories are well capable of determining the sizes of these particles. The analysis of particles in complex matrices or formulations such as consumer products resulted in larger variations in particle sizes within technologies and clear differences in capability between techniques. Sunscreen lotion sample analysis by laboratories using spICP-MS and TEM/SEM identified and confirmed the TiO2 particles as being nanoscale and compliant with the EU definition of an NM for regulatory purposes. In a toothpaste sample orthogonal results by PTA, spICP-MS and TEM/SEM agreed and stated the TiO2 particles as not fitting the EU definition of an NM. In general, from the results of these ILCs we conclude that laboratories are well capable of determining particle sizes of NM, even in fairly complex formulations.

The Data Evaluation of Interlaboratory Comparisons for Calibration Laboratories

National accreditation agencies in different countries have set quite strict requirements for accreditation of testing and calibration laboratories. Interlaboratory comparisons (ILCs) are a form of experimental verification of laboratory activities to determine technical competence in a particular activity. Successful results of conducting ILCs for the laboratory are a confirmation of competence in carrying out certain types of measurements by a specific specialist on specific equipment. To obtain reliable results of ILC accredited laboratories, it is necessary to improve the methods of processing these results. These methods are based on various data processing algorithms. Therefore, it is necessary to choose the most optimal method of processing the obtained data, which would allow to obtain reliable results. In addition, it is necessary to take into account the peculiarities of the calibration laboratories (CLs) when evaluating the results of ILС. Such features are related to the need to provide calibration of measuring instruments for testing laboratories. The evaluation results for ILCs for CLs are presented. The results for all participants of ILCs were evaluated using the En and z indexes. The obtained results showed that for the such ILCs it is also necessary to evaluate the data using the z index also.

Novel methodology comparing two assay formats for the assessment of immunogenicity from clinical trial samples

Aim: We present a novel methodology to compare results between distinct immunogenicity assays, performed by two laboratories, for the same biotherapeutic. Materials & methods: Human serum pools from clinical trials were generated to provide representative immunogenicity titers. Pools were evaluated at two laboratories in a blinded fashion to assess the effect of assay format and laboratory change on clinical interpretation of immunogenicity results. Results: The laboratories validated two different assay formats and demonstrated comparable sensitivity and drug tolerance. Overall, the comparisons in assay format and laboratory ensured a comparable ability to detect treatment-emergent antidrug antibodies for a biotherapeutic. Conclusion: We have established an approach, using pooling of patient samples, that allows for the interlaboratory comparisons without creating duplicative results.

Quantitative Metrics for Performance Monitoring of Software Code Analysis Accredited Testing Laboratories

Modern sensors deployed in most Industry 4.0 applications are intelligent, meaning that they present sophisticated behavior, usually due to embedded software, and network connectivity capabilities. For that reason, the task of calibrating an intelligent sensor currently involves more than measuring physical quantities. As the behavior of modern sensors depends on embedded software, comprehensive assessments of such sensors necessarily demands the analysis of their embedded software. On the other hand, interlaboratory comparisons are comparative analyses of a body of labs involved in such assessments. While interlaboratory comparison is a well-established practice in fields related to physical, chemical and biological sciences, it is a recent challenge for software assessment. Establishing quantitative metrics to compare the performance of software analysis and testing accredited labs is no trivial task. Software is intangible and its requirements accommodate some ambiguity, inconsistency or information loss. Besides, software testing and analysis are highly human-dependent activities. In the present work, we investigate whether performing interlaboratory comparisons for software assessment by using quantitative performance measurement is feasible. The proposal was to evaluate the competence in software code analysis activities of each lab by using two quantitative metrics (code coverage and mutation score). Our results demonstrate the feasibility of establishing quantitative comparisons among software analysis and testing accredited laboratories. One of these rounds was registered as formal proficiency testing in the database—the first registered proficiency testing focused on code analysis.

Interlaboratory comparisons of calibration results of a multifunctional calibrator of electrical quantities

Article is dedicated to organization and conduct of the calibration results of reciprocal interlaboratory comparisons for the multifunctional calibrator of electric quantities: DC voltage, AC voltage, DC current and AC current. The interlaboratory comparisons of electric quantities measurement instruments calibration results are represented. Evaluation of the laboratory calibration results bias is provided using the modified criterion. Analysis and conclusions concerning participating laboratory competence are provided.

Characteristics improvement of pressure transfer standard using a silicon resonant sensor

<p>In the field of pressure measurement, numerous interlaboratory comparisons are carried out among National Metrology Institutes (NMIs) using a pressure transfer standard to verify the degrees of equivalence. Here, the Yokogawa electric corporation has been producing a series of digital manometers using a silicon resonant sensor developed independently. This sensor demonstrates excellent long-term stability and has thus been adopted as the pressure transfer standard by many NMIs and has been subsequently well received. The pressure transfer standard is known as the resonant silicon gauge (RSG) among NMIs. From December 2016, the National Metrology Institute of Japan (NMIJ), the Advanced Industrial Science and Technology (AIST) institute, and Yokogawa initiated a collaborative research with the aim of improving the characteristics of the RSGs and developing a portable transfer standard using a new silicon resonant sensor. The new RSG was adjusted using a standard device calibrated by either NMIJ or Yokogawa. The measurement values of the standard device were corrected with the calibration results and used as the standard values for adjustment of the new RSG. The linearity of the new RSG adjusted via the proposed method was improved compared with that of a conventional RSG.</p>