In the International System of Units, the impedance units can be realized from the quantum Hall effect, a macroscopic quantum phenomenon producing quantized resistance values. Established experiments employ individual GaAs devices, but novel materials such as graphene can be exploited to realize the units with relaxed experimental conditions. Furthermore, simple traceability chains can be implemented with novel digital impedance bridges. By combining novel digital impedance bridges and graphene quantum standards, an easy-to-operate and affordable impedance standard has been developed in the framework of the European EMPIR project 18SIB07 GIQS (Graphene Impedance Quantum Standards). An onsite comparison of an electronic and a Josephson impedance bridge developed at INRIM (Istituto Nazionale di Ricerca Metrologica, Italy) together with POLITO (Politecnico di Torino, Italy) and at PTB (Physikalisch-Technische Bundesanstalt, Germany), respectively, were organized for their mutual validation in the realization of the farad from graphene quantum standards. The result of the comparison and the last progresses of the GIQS project are here presented.

The paper reports an interlaboratory comparison of low impedance measurements at frequencies relevant for electrochemical impedance spectroscopy (EIS) of commercial lithium-ion cells. The comparisons cover an impedance range from 50 μΩ to 100mΩ across the full complex plane in a frequency range 0.01 Hz up to 5 kHz. A first comparison covered calibration of low impedance standards by reference digital sampling impedance setups in 4-terminal and 4 terminal-pair connections. A second comparison used commercial 4-terminal EIS meters to measure the low impedance standards characterised in the first comparison.

This paper introduces a novel Multiwaveletbased hybrid method of Compressed sensing (CS). A case study of CS and reconstruction of Electro Cardio Diagram (ECG) signals with the presented method was performed. For ECG signals the proposed method does not require a wave position detector and can reconstruct the signal with minimal DC offset error. The method is completely patient-agnostic and does not require prior patient-specific information as well. The proposed method was evaluated using the MIT-BIT database. The obtained results show a good reconstruction quality while keeping a high compression ratio.

The paper presents a pilot study over human exposure to radiofrequency (RF) electromagnetic field (EMFs) levels generated by the 5G cellular base stations installed in different residential district in city of Iasi, Romania.Also, a comparison with different EMFs levels generated by different mobile phonetechnologies, from our national operators, have been done. Measurement of electromagnetic field levels (instantaneous exposure) expressed in terms of power density levels has been performed in city of Iasi, fom March to November 2021, in nine locations with a high density of cellular base stations. The EMF exposure levels for different mobile communications standards have been measured with an up to date calibrated NARDA SRM 3006 field strength analyser system connected to an isotropic electric field probe. The methodology for measuring the non-ionising electromagnetic radiation levels described by ECC RECOMMENDATION (02)04have been respected.

This paper presents metrological evaluation of bidirectional electricity meters, comparing its performance when measuring electrical energy in direct and reverse power flows. Evaluation results shown that the difference between measuring results in both directions is not significant compared to the measurement uncertainty and to the maximum permissible errors. In this evaluation, four IEC 0,2S and 0,5S accuracy classes electricity meters were tested.