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The cornerstone of the study is to quantify the ²²²Rn/²²⁰Rn levels and the associated health risk in the environment of a heavy mineral-rich area in India. ²²²Rn and ²²⁰Rn activity was measured in environmental resources like soil, water, and indoor air. The analysis was performed using a well-calibrated online ²²²Rn/²²⁰Rn monitor (RAD 7) which is having a solid-state semiconductor detector system. The ²²²Rn depth profile in soil gas and exhalation rates of ²²²Rn and ²²⁰Rn from soil were monitored. The measured ²²²Rn activity in the indoor air of the study area concluded an effective radiation dose of 0.44–1.81 mSv.y⁻¹ and an ELCR of 0.17–0.7%. Groundwater and surface waters from the high-background-radiation area were also analysed for dissolved ²²²Rn activity which contributes to a total radiation dose from 2.7 to 21.4 µSv.y⁻¹.

The rapid population growth has raised the need of industrialization which has opened a new horizon for the additive manufacturing, especially in the area of 3D printing technology. 3D printing has immersed as the additive manufacturing technique which finds its application in every domain including toys, confectionaries, biomedical, electronics, aerospace and automobile. But achieving the desirable surface finish is a difficult task for 3D-printed material especially poly lactic acid (PLA). Due to less material removal in traditional abrasive flow machining, the scope of the current investigation is to finish 3D-printed hollow cylindrical workpiece made of PLA material by Fused deposition method using Centrifugal force-assisted abrasive flow Machining process. The investigation was carried out to determine the optimum percentage improvement in surface finish and surface micro-hardness using Response surface methodology. Using an optical profilometer and a micro-hardness tester, the surface characteristics of the workpiece were examined. Additionally, wear modeling was carried out using the Ansys^® software, and the outcomes were confirmed through tests using Reye–Archard–Khrushchev wear law. The simulation results were in good confirmation of experimental results with total debris of 1.4 mg. The findings of the investigation indicate an average improvement in surface quality of 39.27%. The experimental results show that the major influence on enhanced R_a and micro-hardness comes from CFG rod rotation. Also, the ideal percentage improvements in surface finish and micro-hardness are found to be 35.34% and 41.29 HV, respectively.

Precision and traceable measurement of small forces have become increasingly important due to the rapid change in technology and miniaturization of devices. In this paper, we have discussed the design, development and metrological aspects of double bending beam force transducer for low-force measurements. To achieve this task, elastic spring element  is designed and machined for fabricating the force transducer and virtually tested through the finite element analysis (FEA) method to validate its load capacity and to understand its mechanical behaviour. The metrological capability of spring element is determined with the application of small forces, sensing the applied forces through contact and non-contact methods. In the contact method, strain gauges are employed for the detection of induced strain on the spring element. For this, the maximum and minimum strain values and their distribution are found to get the optimum normalized output in the electrical unit of mV/V. In the non-contact method, a pair of light-emitting diode (LED) and light-dependent resistor (LDR) is utilized for the detection of the bending caused by the applied force. The optimal detectable deflection is found in the spring element through FEA. The experimental characterization results of the force transducers showed that the developed force transducers have good metrological capability in terms of high linearity and repeatability in the range of 0.3–3 N.

The present study focuses on determining the post COVID 19 status of air pollution and temporal variability of pollutants over the Okhla industrial area, New Delhi. The 24 hourly concentration datasets of PM₁₀, PM_2.5, NO₂ and SO₂, for the period of November 2021 to November 2022 were collected from continuous ambient air quality monitoring station of study area. During the study period, the concentration of PM₁₀ and PM_2.5 was observed to be varying from 9.73 to 640.14 µg/m³ and 6.18 to 448.06 µg/m³, respectively. The average values of PM₁₀ and PM_2.5 were recorded as 236.57 and 107.33 µg/m³, respectively; which were much higher than the standard values of Central Pollution Control Board. In case of gaseous pollutants, the mean value of SO₂ was recorded as 9.31 µg/m³ which was much lesser as compared to the set standards. Contrary, the values for NO₂ varied from 14.75 to 219.36 µg/m³ and these values were on the higher side when compared with standards. The Bivariate plots were also drawn to examine the role of wind speed and wind direction in the study area. The results revealed that at low wind speed, high concentrations were prevailing and potential sources of pollutant are in south east direction. Overall, the results of this study highlighted that situation is alarming after COVID 19, and need immediate intervention for the abatement of air pollution in studied region.

In the present paper, we have developed an innovative algorithm to improve the oscillometric waveform detection to increase the measurement of blood pressure (BP) accuracy. Most of the techniques for BP measurement are based on the extraction of the oscillometric waveform (OMW) from baseline pressure generated in the cuff. The physiological changes in the human body provide irregular shapes, magnitudes, and patterns in OMW. Besides human physiological activities, motion artifacts may affect the OMW during the BP measurement. The BP measurement using direct extraction followed by envelope construction shows significant errors beyond the permissible limits. To rectify this problem, a new algorithm is required. This work demonstrates a novel algorithm to improve OMW by creating a zero baseline. The proposed algorithm is performed on low to high BP values, giving better results than the conventional algorithm used on OMW. The systolic and diastolic values of blood pressure obtained from the developed algorithm are within the error limits of international protocol, i.e., American Association for the Advancement of Medical Instrumentation/European Society of Hypertension/International Organization for Standardization (AAMI/ESH/ISO).

The LF & HF voltage, current and microwave metrology section of the CSIR-National Physical Laboratory plays an imperative role in the metrological investigations in the country as it follows the lawful obligations of the NPL charter of developing and maintaining national standards of HF voltage, LF voltage and current, phasor measurement unit and microwave power parameters. For over three decades, the section has been religiously dedicated to performing national obligations and delivering national calibration, testing and measuring services. Still, there is inadequate awareness, insight and perception related to the role of metrological traceability, calibration and measurement capabilities (CMCs) to the clients, academia, industries and government laboratories. Hence there is a dire need to educate and provide the required information to the end users. Keeping this in mind, this paper provides necessary details of the facilities, technologies and CMCs of the section to the common masses. The International Bureau of Weights and Measures (Bureau International des Poids et Mesures) and Asia Pacific Metrology Programme key/supplementary comparisons are also described in the paper, which has helped the group improve and attain greater heights.

This paper presents the design and evaluation of a Multi-function torque standard machine (MFTSM) capable of calibrating hydraulic torque wrenches, torque multipliers either concentric or nonconcentric up to 100 kN m, and torque transducers with regular or irregular bases up to 2.5 kN m, in clockwise and anticlockwise directions. The machine’s performance was evaluated through a series of calibrations and comparisons that revealed good consistency, as the E_n value tests are less than unity.

Coronavirus disease (COVID-19) has changed the living environment in various aspects just like any other disaster. The goal of this study was to use time series remote sensing data to analyze vegetative cover change in the Western ghats of south India from January 2018 to June 2021 (pre & post covid scenario). In this context, biodiversity in terms of Normalized Differential Vegetation Index (NDVI) has been investigated in relation to variations in anthropogenic activity levels before and after the Covid-19 period. A spatio-temporal analysis of NDVI, LULC change, rainfall and AOD in relation to lockdown due to Covid-19 was conducted in this study. The study demonstrates the adaptability of remote sensing techniques and GIS for monitoring the changes in biodiversity in a more precise and cost-effective way, which is ideal for conservation planning and prioritization. Also, this study investigates the relationship between rainfall, AOD and NDVI during the study period. The results show that some parts of the Western Ghats which lies in Chamrajnagar of Karnataka, Erode and Dharmapuri of Tamil Nadu experienced significant vegetative cover change during the study period. It is also been inferred that there are changes in vegetative cover along the transect points situated in Shimoga of Karnataka, Palakkad and Idukki of Kerala due to the outbreak of forest fires. The restriction during the Covid-19 lock down has minimized the disturbance in the Ghats region which echoed in the increase in vegetative cover as well as areal extent of water bodies during post corona period (2021). The effect of increase in rainfall has reflected in the reduction in concentration of aerosol due to wet scavenging effect.

ISO/IEC 17043:2010 is a widely recognized standard for proficiency testing providers. Recently, a new version of the standard, ISO/IEC 17043:2023, has been released, which introduces some changes and improvements to the previous version. The new standard has been harmonized with ISO/IEC 17025:2017 and ISO 13528:2022 standards in terms of structure and content. This article aims to provide an overview of the changes made to the standard and their implications for proficiency testing providers. The revisions include a greater emphasis on risk assessment, participant selection, performance evaluation, reporting, and data protection. These changes are intended to improve the quality and consistency of proficiency testing and ensure that results are accurate, reliable, and trustworthy.

This study investigated the interruption-recovery pattern of air pollutants (O₃, PM_2.5 and PM₁₀) during and after the COVID-19 pandemic in Southern Brazil using machine learning models. The results showed that 2020 was an atypical year for air pollution levels due to restriction measures. However, we also found that 2021 was not a definitive year for the assessed air pollutants in the region but rather a transitional year. It was only in 2022 that the pollutant levels returned to usual levels in the region. In this sense, our findings suggest that the levels observed in 2022 can be considered the "new normal" for air pollutants in the region. Furthermore, we found that O₃ levels decreased significantly and were sustained and further decreased in 2022, while PM_2.5 and PM₁₀ levels showed a reversed but similar trend with a slight increase in concentrations from 2020 to 2021 and again from 2021 to 2022. Overall, this study provides valuable insights into the impacts of COVID-19 on air pollution levels and highlights the need for continued efforts to improve air quality in the region.