Highly excited Rydberg states enable broadband electric field sensing through Electromagnetically Induced Transparency (EIT) and Autler-Townes splitting (ATS). These quantum-optical phenomena allow detection of electromagnetic fields over a wide frequency range from MHz to THz. In this work, we demonstrate multi-band microwave electric field sensing and investigate the variation in threshold power required for AT splitting across the Ku, K, and Ka bands using a Rydberg atomic vapor cell, along with the detection of amplitude-modulated (AM) signals. The microwave field couples adjacent Rydberg states, producing AT splitting in the probe transmission spectrum, from which the electric field amplitude is determined. The modulation information encoded on the microwave carrier is observed as variations in the probe transmission within the EIT resonance, which in turn influence the AT splitting. Since the electric field is obtained from the measured splitting governed by fundamental constants, the method provides SI-traceable measurements and enables a calibration-free approach to local electric field sensing. These results demonstrate the potential of Rydberg atomic systems for broadband microwave sensing and time dependent signal detection.
The National Metrology Institute of Japan (NMIJ) organized and conducted an interlaboratory comparison of sound level meters to technically support emerging National Metrology Institutes in the Asia Pacific Metrology Programme (APMP). Two class 1 sound level meters were circulated among the participating institutes. Each participant was asked to determine the A-weighted free-field response level of the sound level meters using a normal calibration method at frequencies from 31.623 Hz to 19.953 kHz. This paper presents analysis results and discussion of this comparison. We examined the stability of the sound level meters using NMIJ’s calibration results for monitoring and revealed that both sound level meters changed their characteristics during circulation. We confirmed that for each sound level meter, the time-dependent change in the free-field response level was caused by the instability of the microphone attached to the sound level meter. Although neither sound level meter had an acceptable level of stability during circulation, we evaluated the variations in the free-field response level calibrated by each participant, considering the objective of this comparison. We found that the variations among the participants were greater than expected at several frequencies, and in most cases, the unexpected variations surpassed the time-dependent change in the free-field response level due to the microphone’s instability. Preparing for the next stage, in which the participants would improve their calibration procedure and/or uncertainty estimation, we proposed measures to mitigate the instability of a microphone supplied with a sound level meter and verified their efficacy.
This paper discusses the indigenously developed experimental model of 1–10 g Kibble balance. Fabrication of setup is discussed in brief. The developed balance is tested for 1, 2, 5, and 10 g. The current study has focused on the measurement of the induced voltage and the product BL in the velocity mode and the associated uncertainties. The test measurements carried out with the different masses have uncertainties lower than 1
To investigate changes in water quality in the Inner Mongolia of Yellow River Basin (IM-YRB) and to elucidate the relationship between climate and water quality, this study employed the Water Quality Index (WQI) method, based on six water quality parameters, to conduct a comprehensive assessment of water quality from 2010 to 2020. The results showed that: 1) Temperature, precipitation and runoff in the IM-YRB showed an increasing trend from 2010 to 2020. Significant negative relationship was detected between temperature and chemical oxygen demand (COD), runoff and NH3-N. Runoff exhibited a strong positive correlation with fluoride (F−) (p < 0.05). 2) The variation of water quality parameters exhibited a decreased trend from 2010 to 2020. The highest concentration of Permanganate index (CODMn) and NH3-N respectively was 3.47 and 0.33 mg/L in 2011. The concentration of COD (14.89 mg/L) and Five-day biochemical oxygen demand (BOD5) (3.21 mg/L) exhibited a decreasing trend since 2013. TP showed a decreasing trend since 2012, with a minimum of 0.06 mg/L in 2018. The mean concentration of F− was 0.44 mg/L with a decreasing trend from 2011 and a minimum of 0.32 mg/L in 2019. WQI was significantly improved since 2015. The linear mixed-effects model indicates that NH3-N, CODMn, and total phosphorus (TP) were the primary parameters influencing the WQI from 2010 to 2015. NH3-N, CODMn, and COD were the primary parameters influencing the WQI from 2015 to 2020. 3) Significant spatial differences in water quality parameters (p < 0.05). The water quality of the Meidaigou river, Wulanmulin river, and Hun river station remained good state. Kundulun river, Xi river, Xiaohei river and Dong river remained poor state.This study provides a basis for understanding changes in water quality in the Inner Mongolia region of the Yellow River Basin and offers guidance for water pollution prevention and control efforts in the basin.
The global trend of rising electricity consumption underscores the importance of measuring large currents, and measurement results must be traceable to meet legal metrology requirements. This research aims to provide metrological traceability in the dissemination of the alternating current unit, considering the scale factor of instrument current transformers. The calibration and measurement capabilities declared in the KCDB of the International Bureau of Weights and Measures (BIPM) include characterization of ammeters, thermal current converters, and shunts in the current range up to 100 A, as well as current transformers from units of amperes to tens of kiloamperes. Today, measurement results obtained with current transformers are considered linked to those reproduced by national standards of alternating current scale factors, associated with the turns ratio of primary and secondary windings. One of the main metrological characteristics of current transformers is the ratio error, which is usually determined through calibration and, consequently, relates to the reference ratio error known with the lowest measurement uncertainty. Considering the ratio error as a non-SI quantity, the authors propose an alternative approach to the characterization of current transformers, clarifying the aspects of traceability establishment through the use of precision thermal converters and current shunts, and creating a clear link to SI units. The connection to electrical quantities such as DC voltage, DC resistance, capacitance, and inductance is analyzed and established through a current transformer calibration by a measurement setup with AC/DC transfer for a new purpose. Theoretical notes and analyses of relationships among the main elements of a measurement setup are also presented, along with a newly derived mathematical model and uncertainty budget. Overall, a traceability diagram for high alternating current measurements using a current transformer to SI units is provided based on the outlined approach.
The rapid advancement of highly precise manufacturing technology has facilitated much research to be carried out in the area of multi-sensor capacity and data synthesis expertise. The research aims to establish a detection system that improves surveillance capacities. The accuracy and efficiency of production are improved through precision accuracy and data abundance. A single sensor cannot fix the factors affecting the detectors in a mining gas surveillance system. The multi-sensor data fusion technique improves the system's information utility, precision, dependability, and error tolerance. Each sensor individually detects specific characteristics in a multi-sensor system.Zhang in EURASIP Journal on Advances in Signal Processing 2021:1–18, 2021 Using an appropriate signal-processing technique, the system then combines the total individual capacities into a complete measurement data set.The Industrial Revolution has made manufacturing companies smarter, which has required the creation of multi-sensors. Several sensors are employed in the industrial monitoring of personnel and machinery to identify events, optimize production processes, reduce associated costs, and improve safety.
According to the SDG Report 2025, by 2040, over 2 billion urban residents may experience temperature increases of at least 0.5 °C, and nearly 36
To develop management strategies to control human-induced air pollutants, it is important to examine the chemical species that influence PM2.5 concentrations and to quantify PM2.5 concentrations in urban environments. The present study examined the 24h average PM2.5 levels from July 2018 to December 2019 at three locations in the Indian Himalayan Region: Darjeeling, Almora, and Mohal-Kullu. During the measurement period, the average mass concentrations of PM2.5 were as follows: Mohal-Kullu, 39 ± 21 (range: 13–98 µg m−3); Almora, 27 ± 18 (range: 11–109 µg m−3); and Darjeeling, 38 ± 13 µg m−3 (range: 16–89 µg m−3). A significant positive correlation among NH4+, SO42−, NO3−, and Cl− in PM2.5 at the p < 0.05 significance level indicated formation of secondary inorganic aerosols (SIA) at the study sites. PMF 5.0 identified three to five major sources over the study sites: fossil fuel combustion, secondary aerosols, vehicular emissions, soil dust, and biomass burning. In Darjeeling, the five dominant sources were coal combustion (26
The non-biodegradability and inherent toxicity of petroleum-based lubricants have created a strong need for environment friendly bio-based alternatives. Biolubricants enriched with nano-additives serve as a highly effective and sustainable alternative to conventional mineral oils. In this work, a set of bio-oil based mono and hybrid nanolubricants were prepared. Nanoparticles of CuO were used to develop mono nanolubricant and CuO along with MWCNT was utilized for synthesizing hybrid nanolubricant. Nanoparticles were added in a range of 0.02
This paper presents the design, fabrication and validation of the single layer planar search coil along with its integration with developed magnetic field measurement software (FPGA driven) using Moku:Go. The developed device is capable of measuring an unknown magnetic field without prior knowledge of its frequency. It can also measure and display the frequency of the magnetic field. The developed device is validated in measuring AC magnetic field range from 1 milligauss-2000 milligauss (100nT–200µT) over frequency range 50 Hz–60 kHz with sensitivity varying from 1 µV/mG (at 50 Hz) to 0.93 mV/mG (at 60 kHz). The performance of developed device has been compared with the commercial magnetometer and results show remarkable closeness with maximum relative error of 5.33
A decade long integrated assessment of physicochemical, radiological parameters was carried out over 1500 km2 in the northeastern coastal region of Andhra Pradesh, India. Approximately 1300,130, 40 ground, drinking, surface water samples were analysed for conventional water- quality parameters, uranium, and gross alpha/beta activity. Mean groundwater concentrations of TDS, hardness, chloride, sulphate, nitrate, phosphate, and uranium were 1187 mgL−1, 251 mgL−1, 264 mgL−1, 76 mgL−1, 23 mgL−1, 2.4 mgL−1, and 3.9 µgL−1, respectively, all within regulatory limits. Most groundwater parameters exhibited positive skewness with kurtosis > 3, indicating leptokurtic distributions typical of environmental datasets. Uranium exhibited moderate positive correlations with EC (r = 0.37), TDS (r = 0.34), salinity (r = 0.39), chloride (r = 0.35), and sulphate (r = 0.29). Mann–Kendall trend analysis revealed a statistically significant decreasing trend in TDS and chloride at a representative location, indicating reduced saline influence, while uranium showed a weak but statistically insignificant increasing trend. Gross alpha, gross beta, and uranium activities were well below regulatory limits, and the estimated annual effective dose (< 0.1 mSv y−1) indicates negligible health risk. The study establishes a first comprehensive pre-operational baseline statistics essential for long-term environmental monitoring and assessment of future anthropogenic or nuclear-related impacts in the region.
Progress of drug risk assessment heavy metals and harmful elements in traditional Chinese medicine improving globally is slowed by limited understanding of heavy metals and harmful elements contents. This challenge becomes more complex when slight variations in measurement could affect the determination of heavy metals. The objectives of this study are to evealute the applicability of the existing standard methods suitable for determination heavy elements. A case study using two analytical methods, namely inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrometry (AAS), for the determination of lead and cadmium in PAEONIAE RADIX ALBA from two certified reference materials (ID: WPH240202024; ID: WPH240202025) with microwave digestion, wet digestion and dry ashing methods was conducted to evaluate their capacity to provide reliable and precise results. Instrument performance assessment was evaluated using limit of quantitation, limit of detection, precision, and calibration curve. Accuracy and precision of lead and cadmium contents were evaluated by the relative standard deviation. Based on the results of the two heavy elements, the analytical uncertainty has also been evaluated and the source of analytical uncertainty in all analytical and digestion methods was quantified identified. The results of the calibration curves for lead and cadmium of two analytical methods had a correlation coefficient greater than 0.999, which indicates that the linearity is good. The recovery rates for lead and cadmium using the two analytical methods ranged from 98.3
Based on the measurement principle of ultrasonic gas meters, this paper establishes the measurement models of the instantaneous flow method and the cumulative flow method respectively. The gas meter verification device compatible with both instantaneous flow method and cumulative flow method has been innovatively developed. Experiments were conducted to evaluate the equivalence between the instantaneous flow method and the cumulative flow method. The experiment proved that the instantaneous flow method can effectively eliminate the influence of the tail number of the cumulative flow method on the measurement error. Under the premise of ensuring the reliability of the verification results, the lower limit value of the effective measurement time of the instantaneous flow method was sought by constantly changing the measurement time. The experimental results proved that the measurement time in the high zone could be shortened from 60 to 5 s, and in the low zone from 600 to 60 s by the instantaneous flow method. Moreover, the detection efficiency was more than 10 times that of the cumulative.
Laboratory testing becomes utmost important due to the lack of real live-sky signals, however testing IRNSS receivers with different environmental conditions is a challenging task for GNSS researchers and engineers. Generating test signals in the lab that are similar to the real-time atmospheric and channel conditions is the way of evaluating and testing the performance of the IRNSS receiver rather than collecting IRNSS samples every time from the live satellites. Generation of a state-of-the art IRNSS signal simulator with channel modelling has the provision to change the signal characteristics as per the user requirement and is the mandate one for deploying IRNSS service in the Indian subcontinent region. Therefore, there is a need for software-based IRNSS data simulators for the design and development of versatile IRNSS receivers. In this work, we present a MATLAB-based simulator module designed to address this need. The Parameter Computation Unit of the module formulates the navigation data, consisting of four sub-frames with 2400 bits each, using legitimate encoding algorithms. Additionally, the Signal Formation Unit generates a C/A code of 1023 bits, which is combined with the navigation data and modulated onto a user-assigned Intermediate Frequency (IF). Subsequently, the digitized IF data for multiple satellites are compiled into a file format compatible with software IRNSS receivers, allowing for comprehensive validation of various signal processing modules. Moreover, the multipath fading model has also been simulated to analyze the BER for slow and fast receiver dynamics. The proposed simulator provides an improved performance, resulting in a reduction in horizontal positioning error by 13.95
Disaster Risk Reduction (DRR) is increasingly determined by the quality of measurements, standards, institutional competence, and verification mechanisms that govern complex socio-technical systems. In infrastructure-intensive and hazard-prone economies, disaster risk is not merely an external contingency but a cumulative outcome of how physical, industrial, and digital systems are measured, regulated, and operated across their lifecycle. This article advances a measurement-based governance framework for DRR by extending the Aswal Model of National Quality Infrastructure and integrating metrology, standardization, accreditation, and conformity assessment into the disaster risk reduction cycle. The framework places continuous, traceable, and uncertainty-aware risk assessment—covering hazard, exposure, vulnerability, and capacity—at the core of governance, while interpreting preparedness, mitigation, response, and recovery as parameter-driven and auditable functions. A traceable measurement-to-governance chain is introduced to demonstrate how calibrated observations and validated models, supported by uncertainty characterisation and standards-based traceability, translate into decision thresholds, regulatory instruments, and operational actions, with audit and feedback enabling continuous improvement. The paper further shows how national disaster-risk policy, including the Prime Minister’s 10-Point Agenda on Disaster Risk Reduction, can be operationalised through existing quality-infrastructure mechanisms without institutional duplication. By embedding DRR within national quality infrastructure systems, the framework strengthens regulatory coherence, institutional reliability, auditability, and adaptive learning, highlighting the expanding role of measurement science as a foundational instrument of credible and resilient risk governance.
In India, the installation of rooftop PV plants is rapidly growing among domestic and commercial users. To assist such users, the present study covers a detailed one-year performance study of a 100 kWp PV plant in the composite climate of central India. Additionally, mathematical models are also developed for finding the impact of higher PV cell temperature on PV plant performance as measured under IEC 61724 standard, along with emphasis on CO2 mitigation, energy metrics, and the levelized cost of electricity (LCOE). The system is performing well, as indicated by annual average final yield of 4.04 kWh/kWp/day, a system efficiency of 10.33
Spoofing disrupts the normal behaviour of GNSS signals by introducing subtle but measurable changes in key observables. Detecting such attacks requires the receiver to distinguish these abnormal patterns from the naturally stable characteristics of genuine signals. This study evaluates the vulnerability of NavIC to spoofing through a series of controlled static experiments and assesses the performance of commonly used statistical detection techniques. The analysis focuses on pseudorange and Doppler measurements, as these parameters consistently show early deviations when counterfeit signals are introduced. To the best of our knowledge, this is the first study that systematically compares multiple statistical detection frameworks (e.g., the Generalized Likelihood Ratio Test (GLRT), Mahalanobis distance) using NavIC-specific observables such as inter-satellite pseudorange and Doppler variance under spoofing conditions. Among the approaches examined, the Generalized Likelihood Ratio Test (GLRT) demonstrates the most reliable detection capability across different spoofing conditions. Time-series observations further highlight the inherent stability of NavIC’s GEO/GSO satellites, which restricts the effectiveness of spoofing attempts by making departures from normal behaviour more noticeable. The results suggest that NavIC’s constellation geometry naturally supports early spoofing detection, and that coupling these features with machine-learning-based classifiers in future work could enhance robustness against a wider range of spoofing strategies.
Online weather forecast system usually works over a large geographical area. However, it has been noticed that, due to uneven altitude zones specially in the hilly areas, there are some flaws in accuracy found in meteorological parameters of smaller regions within same coordinates. This paper presents a solar powered local weather measurement and prediction system both for plains and hilly regions using Internet of Things (IoT) and Random Forest Regressor. An ESP32 microcontroller, paired with the temperature, humidity and Atmospheric pressure sensors used to facilitate real-time meteorological data monitoring. The proposed system incorporates online weather data for comparison with local-sensor parameters within same coordinates to track out the minor changes. These minor changes feed into the Random-Forest Regressor algorithm for improvement in measurement and prediction accuracy. With 98
Surface roughness critically influences biocompatibility, wear resistance, and clinical success of medical implants. This study quantitatively evaluates the nano-topography of a Bipolar Hip Joint—a key prosthetic implant used in hip replacement surgeries—using stylus profilometry (Mitutoyo CS-5000 CNC; contact method) and optical profilometry (Wyko NT9800; non-contact method). Comparative analysis revealed a significant methodological divergence in average roughness (Ra) values: 89.32 nm (stylus) versus 67.20 nm (optical). This variation underscores fundamental differences in spatial resolution and measurement principles between contact and non-contact techniques. This study established that surface characterization methodology critically influences roughness quantification of orthopedic implants with optical profilometry, demonstrating superior reliability for nano-scale characterization. Both methods independently confirmed that Bipolar Hip Joint possesses a smooth surface, with Ra values conforming to the acceptable range established by Albrektsson and Wennerberg.
Although tinnitus masking therapy is widely used clinically, objective audiometric evidence quantifying its effect on tinnitus pitch, minimum masking level (MML), and residual inhibition remains limited. To prospectively evaluate the effectiveness of personalized tinnitus masking therapy using standardized pure tone audiometry and psychoacoustic measures.Thirty-one adults with chronic tinnitus underwent baseline audiological evaluation including PTA (250–8000 Hz), pitch matching, loudness matching, MML, residual inhibition testing, and THI scoring. Participants used individually programmed CiC tinnitus maskers for six weeks (2–4 h/day). Pre- and post-intervention measures were compared using paired t-tests. Significant reductions were observed in tinnitus pitch (right ear: 6687 ± 2840 Hz to 6139 ± 2942 Hz, p = 0.049; left ear: 6527 ± 3842 Hz to 6044 ± 2821 Hz, p = 0.040) and MML bilaterally (p < 0.05). Air conduction thresholds showed mild improvement, while bone conduction thresholds remained stable. Residual inhibition duration increased with longer masker exposure. Personalized tinnitus masking therapy produces measurable reductions in tinnitus pitch and MML without affecting cochlear integrity. These findings provide objective audiometric evidence supporting individualized sound therapy in chronic tinnitus management.
