The preface discusses the summary of the special issue consisting of 24 peer-reviewed papers on the theme Advances in Sensors and Measurements for Metrological Applications. These papers discuss the state-of-the-art reviews by highlighting various technological innovations, processes developed pertaining to the design, development as well as characterization of sensors, their measurement methods/strategies

Until recently, the kilogram was the only SI base unit having an artifact as its primary standard. For more than four decades, there have been continuous efforts worldwide toward redefining the kilogram, the SI unit of mass, to have an artifact-independent and time-invariant definition based on a fundamental constant. Due to the effort of metrologists across the globe, on 16th November 2018, in the

The impact of climate variability on wheat crops has been estimated using classical and neutrosophic approaches. Temperature and rain have been incorporated as the indicators of climate variability during wheat growth phenology and taking wheat yield as a dependent variable. A comparative analysis of estimated results under the classical approach with the neutrosophic approach has been performed. The

In this paper, new traceable measurement systems for automatic calibration of high current sources have been established at the National Institute of Standards (NIS), Egypt. These systems can be used in laboratories mainly depending on calibrators with current coils, in case of unavailability of current transformers. Traceability of high current has been achieved to the primary standards of low voltages

The performance improvements of SOnic Detection And Ranging (SODAR) necessitate designing efficient acoustic antennas for the Atmospheric Boundary Layer (ABL) measurements to enhance the data availability of weak echoes. An efficient acoustic antenna needs to optimize electrical to acoustic and acoustic to electrical conversion efficiency measured at the antenna axis. It also needs to provide a good

Sensor design using ultra-wideband (UWB) technology is considered powerful emerging technique to extract information about the state of biological and physiological conditions of human organs for diagnostic purposes. Recently, UWB radio sensor technology is being proposed for early stage breast cancer detection in view of some superior characteristics or bio-markers over current methods. In this paper

Cosine response is an important characteristic of an optical detector for irradiance measurements. The non-ideal cosine response of a detector may lead to errors in irradiance measurements. In this paper, a theoretical simulation of irradiance generated due to isotropic point light sources is carried out for different illumination conditions. Simulation results show that the errors in irradiance measurements

Micropipette is a quite simple, but an essential instrument used for the volume measurements and finds the applications in the field of chemistry, pharmacy, health care, biology, pathology, research and development, etc. The calibration laboratories must ensure that the results obtained using these instruments are accurate, and therefore, the calibration is an inevitable process. This report is on

Park brake lever is a part of the drum brake in an automotive system. This paper seeks to verify a new approach mainly focusing on the orientation of the park brake lever, using a vibrating linear feeding mechanism, and predicts the natural resting behavior of the park brake lever after falling from various heights. An automated system for the park brake lever is developed through analysis and experimentation

Tissue segregation plays a crucial role in the measurement of breast density in breast magnetic resonance (MR) images. This paper proposes a mathematical analysis of the new distribution mixture model for the intensity spectrum of breast MR images using Gamma and Gaussian distribution for fibro-glandular and adipose tissues, respectively. The thorough regression analysis and mapping presented in this

The research work is aimed at providing the metrological service of production and operation of the measuring instruments of alternating current. Approximately a quarter of 200 countries of the world have the calibration and measurement capabilities declared in the KCDB database of International Bureau of Weights and Measures. It means that there is no adequate metrological service for some reference

The photon-counting technique is used where light intensity is extremely low (i.e., in the range of pW to nW) and widely applied in the field of meteorology, space, biotechnology, quantum information, and medical. Various quantum metrology laboratories and research institutes working in the low-intensity light measurement use commercially available SR400 gated photon-counting systems due to their high-count

A correction to this paper has been published: https://doi.org/10.1007/s12647-021-00475-9

Hydrometers are widely used in industry for liquid density measurement. It is important to achieve rapid and high accuracy calibration for hydrometers. Based on the Archimedes principle, a fully automatic hydrometer calibration system in NIM was designed using Cuckow’s method. The liquid density of n-tridecane (C13H28)is calibrated with 441 g high-purity fused silica ring as the solid density standard

Substrate integrated waveguide (SIW) technology has immense applications for the design of microwave components and devices. In this paper, a low loss substrate integrated waveguide (SIW) structure is designed, fabricated and experimentally tested to exploit in S band and C band applications. SIW structures are constructed by interconnecting parallel metallic surfaces with two rows of metallic vias

With the increasing penetration of distributed energy resources into the power grid, the intermittency property of non-conventional sources has made it compulsory to propose an appropriate controlling system so as to have maximum utilization of the clean energy resources. The idea of utilizing a photovoltaic (PV) system inverter integrated with grid as STATCOM is termed as PV-STATCOM has been used

Two-phase flow measurement is a key issue in the natural gas industry. Among the many different flow meters available, the swirl meter stands out for its reliability, ease of maintenance, large measurement range, and strong output signal. In this study, computational fluid dynamics (CFD) simulations were conducted, using RNG k-e turbulence and Eulerian multiphase models, to investigate the gas–liquid

The measurement of the value of acceleration due to gravity (g) plays a very vital role in many industrial and research sectors. To measure the g-value, two different types of methods are studied for obtaining the precise measurement. These methods are based on the simple pendulum method and drop weight method under a controlled environment with an automatic measurement system. Both cases are evaluated

Generating random numbers is prerequisite to any Monte Carlo method implemented in a computer program. Therefore, identifying a good random number generator is important to guarantee the quality of the output of the Monte Carlo method. However, sequences of numbers generated by means of algorithms are not truly random, but having certain control on its randomness essentially makes them pseudo-random

The present study revealed that the traditional cooking practices could load ~ 2.8 ± 1.2 mg/m3 of PM2.5 in the kitchen, leading to womenfolk at risk. The high variability was observed in the measured values as the concentrations were influenced by several factors such as species of fuel wood used, amount of fuel burnt, duration of cooking, ventilation facility in the kitchen, etc. The calculated health

Std-RSF for each element in analytical sample such as gallium matrix was established using aluminum matrix CRM and applied to the quantification of impurities in Ga metals. Three CRMs were used to prepare the calibration curve, and the slope of calibration curve is RSF. Then, Std-RSF was obtained by converting from RSF based on aluminum matrix to RSF based on gallium matrix. As a result, it was confirmed

PM1, PM2.5, PM5, CO and CO2 emission rates and factors of popular mosquito coils, including a low-smoke coil, marketed in India, were estimated by a chamber experiment in conjunction with a mass balance model. Emission rates of PM1, PM2.5 and PM5 from different coils ranged from 1.0–6.3, 7.2–37.3 and 7.2–106.4 mg h−1, respectively, with the low-smoke coil having highest PM1emission rate. Emission factors

Navigation with Indian Constellation (NavIC), also known as Indian Regional Navigation Satellite System (IRNSS), is an independent regional navigation satellite system, designed to provide accurate position information in the Indian subcontinent. Precise time plays a crucial role in any satellite navigation system for providing positioning, navigation and timing services. IRNSS Network Timing Facility

Many instruments and sensors have been invented to measure pressure, with different advantages and disadvantages. Many factors like pressure range, accuracy, sensitivity, reproducibility, dynamic response, and cost are involved in developing a pressure measuring device. This research paper describes the study of variation in the dielectric constant of lead iron tungstate relaxor specimens with pressure

Smart vehicles, capable of exchanging necessary information with each other and transportation infrastructure, have gained much attraction in automotive research. The data are gathered from location, velocity, acceleration and heading measurements, allowing vehicles to make smart decisions regarding safety and other applications. Specifically, accurate prediction of vehicle location measurement is

In rural areas, there is limited monitoring of drinking water quality. Reliable water quality monitoring stations are expensive and require high costs for maintenance and calibration process. In this paper, the development of a sustainable water quality monitoring system is proposed. The green analytics principles were considered for developing the proposed system to reduce the measurement’s time consumption

For satellite image processing using deep learning, the images are first resized to one standard size and then applied to the convolutional neural network(CNN) model to train and test the model. The primary step of preprocessing the images is resizing, which is done by various approaches such as bicubic interpolation, bilinear interpolation, and nearest neighbour interpolation. The impact of resizing

Ultrasonic testing (UT) is one of the most widely used techniques for non-destructive testing. This is an effective method to provide information of the test material like dimension, geometry, and shape. The precise thickness measurement is necessary for many industries to observe the deterioration, destruction and damages in metals, composite structures, pipes, soldering, and welding. In UT, the pulse-echo

Quartz Bourdon-type pressure transducers are used as a secondary standard for high-pressure precision measurements. Such a transducer's calibration value depends on the pressure medium. When employing a pressure transducer for precision measurements using high-pressure gases, the calibration value should be corrected depending on the gas used. Herein, we describe a method for correcting the transducer's

The pixel counting technique (PCT) has recently emerged as a promising method for the measurement of the dimensions of an object, showing significance in the applications like monitoring the traffic on roads, measuring the dimension of a biological sample, and many more. Therefore, measuring the accuracy of PCT is the topic of current research. The focus of our study is to evaluate the percentage error

The CSIR-National Physical Laboratory (CSIR-NPL), the National Metrology Institute (NMI) of India, is a premier laboratory, founded on January 04, 1947, under the umbrella of Council of Scientific and Industrial Research (CSIR), New Delhi, Government of India, by an Act of Parliament. It has now completed 74 glorious years after inception and entered into its 75th year, i.e. Platinum Jubilee Year.

The present article describes the design and development of a universal device for precise and accurate distribution of time or frequency signal, i.e., one pulse per second (PPS) or 10 MHz and 5 MHz sinusoidal signal generated from an atomic clock or ensemble of atomic clocks. The frequency distribution unit provides four identical outputs of excellent stability along with suppression of all high harmonics

An optical fibre link has been established for precise time and frequency transfer utilizing White Rabbit (WR) network. Temperature sensitivity of WR network components on time offset error has been studied in detail. WR node shows significant sensitivity to the ambient temperature variation when it is locked to an external reference frequency. The change in time offset between two nodes reaches up

In recent years, the performance of an interferometric fiber optic gyroscope (IFOG) has been increased a lot and widely used for dynamic angle measurement. In this paper, we present an investigation on measurement uncertainty of the IFOG and propose a comparison angular vibration calibration approach based on an IFOG. The operation principle of the closed-loop IFOG is introduced, and its error model

The present article describes an indigenous design of microcontroller-based photon counter, which is capable of counting the pulses up to maximum of 5 MHz rate. For this purpose, the short-duration pulses received have been broaden to make it compatible with the counter. The developed photon counter has been tested for its functionality to count the number of photons in a specified time bin at different

The variations of meteorological parameters have significant effects on radio wave signals propagating through the troposphere. Proper planning of radio communication links can be achieved by continuous studying of the atmosphere using refractivity profiles to provide baseline data that could be used to mitigate satellite communication outage before the onset of severe adverse hydrometeor environment

The current advances and innovations in sensor technologies attributed to Industry 4.0 serve as the backbone for the inclusive growth of industry and ramping up the economy of any country. Industry 4.0 was basically conceptualized by introducing the Internet of Things (IoT) and Information and Communication technologies (ICT) that serve as an interface between digital and physical world through the

Present work can be used to calibrate inductance standards by utilizing the error evaluated at the same nominal value of reactance of a capacitance standard. Inductance can be determined in terms of capacitance standard by direct measurement of capacitive reactance on the LCR meter. The conventional Maxwell–Wien bridge is currently used at CSIR-NPL to determine traceability to the inductance standard

The measurement of body mass index (BMI) is an important indicator of preliminary assessment of human health. A higher BMI value increases the risk factor for critical diseases, e.g., high blood pressure (hypertension), cardiovascular disease, gallbladder disease, type 2 diabetes, etc. Obesity also increases the risk factor of COVID-19 in patients. BMI, the ratio of mass (in kilogram) to the square

Precise and accurate pressure measurements play a prominent role in several scientific applications. The pressure balances (PBs) are used as a primary standard for pressure measurements which requires utmost accuracy. In the case of calibration and characterization of these PBs, the method of cross-floating is an internationally accepted practice used for the comparison of 2 PBs for determining their

Frequency modulated thermal wave imaging (FMTWI) has been successfully applied in the field of infrared thermography to estimate defects in various structural materials. The paper presents theoretical aspects of three-dimensional mild steel sample for FMTWI to detect flat bottom holes as defects. Furthermore, performance of FMTWI for analytical and simulated approach has been discussed and comparison

In a recently published report, Somak Bhattacharyya et al. 2016 presented a broadband metamaterial absorber based on a single split ring resonator. He proposed that such an absorber can achieve a broadband absorption which is from 6.70 GHz to 15.82 GHz with above 90% absorptivity. In this paper, the absorber proposed Somak Bhattacharyya et al. is recalculated again and justified that to have ignored

National metrology institute (NMIs) has the prime responsibility to design, development and maintenance of the primary pressure standards to establish the traceability chain for the calibration of the sophisticated industrial instruments using various pressure standards like ultrasonic interferometer manometer (UIM), air piston gauge (APG), force-balanced piston gauge (FPG), and optical interferometer

The paper presents a case study pertaining to the analysis of factors affecting the measurement uncertainty in primary calibration of accelerometers at lower frequencies in range of 0.1 to 40 Hz using low-frequency primary vibration calibration standard realized at CSIR-National Physical Laboratory, India. The potential high accuracy and precision in measurement are achieved with a long-stroke exciter

In the precise and accurate metrological activities, there are various types of surface plates (SPs) used in mounting or calibration purposes. It is essential to install surface plate in the laboratory with a minimum self-deformation and resultant least strain due to its own weight and mounting mechanism. Reference datum of the measuring machines, say in case of a pressure balance, requires flatness

In this article, an optical fiber-based intensity-modulated angle measurement sensor is demonstrated for the measurements of small angles in the range of − 100 to 100 arcmin. At the outset, using a step index multimode polymer optical fiber, reflection-based proximity sensor was developed and the response of it is plotted to identify the maximum response region. At this maximum response region, the

When measuring glucose concentration, assuring the reliability of the results is critical, because the clinical diagnosis of pathologies related to diabetes mellitus, as well as their medical treatment, depends on them. One of the most widely used glucose determination methods in clinical chemistry is the GOD-PAP enzymatic method. Hence, a validation process based on the theory of errors, as well as

This article deals with the ABIS II optical sensor from Carl Zeiss Optotechnik GmbH, which is used in the automotive industry to check the surface quality of moulded parts. Within the research, the process of scanning the moulded part using the ABIS II system was examined in detail, and on the basis of this, the most fundamental influences on the accuracy of the scanning and surface evaluation were

Accurate and precise measurement with authentic data dispersion can be considered as a prime tool to realize any technologies at large scale. In the context of thermoelectric technology, a combination of Seebeck coefficient (α), electrical conductivity (σ) and thermal conductivity (κ) are prominent physical parameters that dictate the performance of thermoelectric materials. In this review article

In this paper, a new neutrosophic exponentially weighted moving average (NEWMA) control chart based on the moving average statistic is proposed. Stated differently, the NEWMA chart is used to handle uncertain production numbers. Moreover, a NEWMA design is applied with moving average statistic to get a sensitive control chart for the quick detection of any unwanted process variations. The efficacy

Modern geodetic terrestrial technology involves automatized observations based on an application of robotic total stations. The benefit of such an advanced geodetic instrument is in its high precision sustainability, manipulation simplicity, maximum flexibility, one-person operability and personal error reduction. The paper is devoted to the analysis of results achieved by using such a modern geodetic

The existing Durbin–Watson (DW) test is applied when all observations are determined and certain. The Durbin–Watson test under neutrosophic statistics is presented in this test. The proposed neutrosophic Durbin–Watson test can be applied to test either autocorrelation exists in error terms when neutrosophy is presented in the data. The proposed test statistic is introduced and applied to the data that

The selection of a suitable gridding method for the interpolation of the input dataset has always been a big challenge. In this study, principal component analysis (PCA) was employed to select a suitable interpolator for the mapping of solar irradiation. For this purpose, sunshine duration data obtained from 50 meteorological stations was used to predict solar irradiation based on the Angstrom–Prescott

The study on historical and future variation in precipitation and temperature is needed to develop effective adaptation strategies for changing climate. The present study investigated the potential impacts of climate change on precipitation and temperature and the performance of individual downscaled global circulation models (GCMs) from the Coupled Model Intercomparison Project Phase 5 dataset over

Modular multilevel converters (M2Cs) have become an interesting and attractive topology for DC/AC conversions and vice versa. This converter is an efficient power electronic converter for adjustable speed drives, high-voltage direct current transmission, renewable energy systems and large power supplies. For drive applications, a theoretical background is presented. This paper presents the comparative

Air Pollution from both indoor and outdoor origin contributes significantly to human exposure and is a cause of concern to citizens living in urban as well as in rural India. Today, our lifestyle demands a considerable amount of time to be spent within the indoor environment making quantification, variability and health impact assessment of indoor pollutants a necessity. Till now, sparse information

All measurements have uncertainty and they are not absolute. Therefore, identification, determination and evaluation of critical influencing factors based on recent approaches are important and necessary. Laboratories shall identify and evaluate all components and contributions to measurement uncertainty. In this article, two different approaches for evaluation of measurement uncertainty of arsenic

Single-point diamond turning (SPDT) is a machining process with high levels of profile accuracy and nanometric surface characteristics. SPDT is a leading technology in advanced manufacturing of ultra-precision optical components for critical applications. Different efforts have been undertaken to improve the cutting condition and optimize the machining parameters during SPDT. The implementation of

In analytical methods, the presence of outliers may mislead the experimenters. The existing Cochran’s tests apply to detect outliers when cent percent of observations in the data are determinate. But, when some or all observations are not precise, determined, and certain, the existing Cochran’s tests cannot be applied for detecting outliers in the data. In this paper, we introduce Cochran’s tests and

The presented paper discusses the summary of the special issue consisting of 13 peer-reviewed papers regarding Redefinition of SI Units and Its Implications. The papers discuss state-of-the-art reviews and progress made as of now and ongoing progress regarding the redefinition of SI units at different National Metrology Institutes (NMIs) and academic/research institutes across the globe. Different