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Optical fibres enable to design of new textile-based sensors for an unobtrusive, continuous, and long-term acquisition of photoplethysmography (PPG) signals. However, no research has been done about the accuracy of measuring blood oxygen saturation (SpO2) and the feasibility of PPG-based blood pressure measurement. This proof-ofconcept study examined these aspects for a woven sensing patch applied on the forehead in five healthy participants. During a controlled desaturation study, SpO2 estimation revealed an amplitude of the root-mean-squared error (ARMS) of 3.6%, and acceptable signal quality for blood pressure estimation was achieved for 40% of all data. These results indicate that textile-based sensors can reach the required PPG signal quality to simultaneously estimate multiple vital signs, including blood pressure.

The Type 1 non-uniqueness (NU-1) is the difference between interpolated values at the same temperature in the resistance thermometer subranges of the International Temperature Scale of 1990 (ITS-90) that overlap. The paper argues for a method of evaluating the NU-1 at a given temperature which considers all subranges of the Scale that contain the respective temperature, not only combinations of two, and it proposes mathematical models to determine the values of NU-1 for temperatures above 0 °C. The paper demonstrates that NU-1 is not the right contributor to the uncertainty associated with the realisation of the ITS-90. Therefore, a new concept of Correction for the Type 1 non-uniqueness of the Scale, CNU-1, is introduced and its mathematical model is established. Also, the estimate of CNU-1 and its standard uncertainty are defined and they are assessed through statistical analysis. The values of standard uncertainty determined by the novel methodology do not exceed 0.26 mK and they are smaller than the values given in the specific Guides developed by the Consultative Committee for Thermometry. The proposed models allow authors to single out and analyse the factors that generate Type 1 non-uniqueness of the Scale and influence its value.

The study and the development of measuring methods of thermal conductivity are essential in several engineering applications, since as a consequence of the current justified demands on saving and rational use of thermal energy, the heat transfer with the maximum efficient as possible is of great relevance. The measurement of the water content is also a relevant parameter in several research areas and industrial sectors, since the quantity of water in the substances influences several biological, chemical and physical processes. The aim of this paper is to present an experimental and theoretical study, following the good metrological practices, of a method based on a spherical heat source in order to measure the thermal conductivity of liquids, focusing on water, ethanol and their mixtures, with later determination of the water content of the binary samples.

With a total area of 3 509 600 km2 and a population of over 80 340 000 people, the eight WAEMU countries (the West Africa Economic and Monetary Union) have many products to offer the international market. These products can be classified into three categories: fishery products, agricultural products, and agro-industrial products resulting from the processing in the first two categories. Despite the real independence of these categories, they share a common thread: efficient quality management. The crux of the matter is efficient quality management which denotes both effective and efficient management of the products. While all the theories of efficiency acknowledge a border between effectiveness and efficiency and highlight the complementarity of the two concepts, it is nonetheless interesting to note that the Russian language combines the two concepts into a single word: “effectivnost”. The efficiency of a quality infrastructure is determined by both its effectiveness and its efficiency since a quality product is one that meets the standards in place, has a number of inherent characteristics that fulfil stated requirements, and can be sold within budget limits set by the consumer. In other words, quality must be managed at a restricted cost so that it is not a source of increased production costs. The formal ratification of the SOAMET (West African Secretariat of Metrology), the NORMCERQ (Regional Body of Standardization, Certification and Quality Promotion) and the SOAC (Regional Body of Accreditation) by the eight WAEMU countries through the signing of Regulation No. 01/2005/CM/UEMOA (Scheme for the Harmonization of the Activities of Accreditation, Certification, Standardization and Metrology in the WAEMU) is a very positive step. Nevertheless, both the successful implementation of this regulation and the quality of work that will derive from these organizations depend on the quality of the human factor, i.e. the competence of the people involved. The CAFMET is in a position to help solve what amounts to an equation with several unknowns. Indeed, the CAFMET has an internationally recognized expertise that continues to demonstrate its value to international metrology and standardization authorities.