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The liquid scintillation counting based triple to double coincidence ratio (TDCR) method is a widely employed, direct activity determination technique to standardize pure beta emitters. An “FPGA-based standalone, portable TDCR system” is developed for absolute activity measurement of pure beta-emitting radionuclides. The system has a local 7″ touchscreen display to provide an intuitive GUI for operating the standalone instrument. The portable system will boost the capabilities of users in the field by providing a reference measurement method of radionuclide metrology. In nuclear medicine, the portable system will enable them to calibrate short-lived radionuclides within the dose-administering facility and avoid transporting radioactive sources to standardizing laboratories. The system’s performance is evaluated by comparing the activity determination results of ¹⁴C, ²⁰⁴Tl and ¹⁴⁷Pm radionuclides with the ones from the CIEMAT/NIST method. The comparison shows that the activity measurement results from the system are closely aligned with those obtained using the CIEMAT/NIST method within the uncertainty limits. In this paper, the system’s performance evaluation is presented.

Robotics is intertwined with metrology, including aircraft component inspection, automotive processes, and part geometry optimization. Optimized trajectory planning is essential for reliable robotic arm operation and maintaining quality in inspections and geometric enhancements, as well as autonomous mobile robot navigation. Technically, a path planning is associated as an optimization problem that relies on various parameters such as length minimization problem, smooth trajectory planning, low time/space complexity, and computational load. While considering all these stated parameters, choosing an optimal path to reach the destination is the primary function of path planning techniques. This research paper is focused on the implementation of adaptive bidirectional A* (ABA*) algorithm along with new strategy of flexible controlling points technique (FCP) to reduce the trajectory error by generating smoother trajectory. With the increased number of sharp turns, the wheel skidding error is generated that reduce the reliability of the path planning techniques by increasing the pose estimation error. By conducting multiple trials, the proposed technique has been implemented, resulting in a 100% reduction in the number of collisions. Furthermore, the application of the new FCP technique eliminates all sharp turns, leading to a 38% decrease in time lag uncertainty compared to conventional approaches. The proposed technique improves autonomous navigation by selecting smoother trajectories.

Negative temperature coefficient thermistors have a high degree of nonlinearity in the resistance–temperature curve, which needs to be fitted with equations in practical applications. The effects of the number of selected points and the way of point selection on the fitting results of different equations in the range of (−50 to 100) °C are explored, and the results show that selecting 11 fitting points with the temperature/resistance combination method can improve the accuracy of S–H fitting, which is suitable for fields with lower precision requirements. For high-precision measurements, the Hoge-2 and Hoge-3 equations should be used with a temperature uniformity point selection method, and the optimal number of fitting points is 11 and 6, respectively.

One of the crucial assessments for electricity meters involves the solar radiation test, typically conducted using solar simulators. This work focuses on the modification of the climatic chamber (MKF-240) at the Egyptian National Institute of Standards (NIS) to serve as a solar simulator. To replicate solar test conditions, enhancements such as an aluminum plate and quartz tungsten halogen (QTH) lamps have been integrated into the MKF-240 climatic chamber. Several experimental trials were undertaken to ascertain the optimal number of lamps required to meet testing standards and achieve optimal uniformity within the test area. The solar simulator, designed for irradiance levels up to 1066 W/m², allows for control of output radiation by adjusting the number of illuminated lamps and the distances between lamps and the unit under examination. At maximum irradiance, the simulator demonstrates a remarkable 91.5% uniformity of radiation. To validate its functionality, the solar radiation test was executed on an outdoor electricity meter, exposing it to different loads and varying radiation values. The accuracy of the meter was precisely recorded and analyzed as an essential component of the overall assessment process.

GPS is using three LEO satellites at a distance of 550 kms from earth. Starlink satellite is emerging satellite system operating at 12/14 GHz (downlink/uplink) frequency for internet services. Wi-Fi services are using ISM band at 2.4 GHz. GPS system is operating at 1.5 GHz. The roadside network frequency is 10.9 GHz. On-board unit will be in each vehicle having all these five antennas. Wireless toll collection systems can be integrated with all these services in the vehicles travelling at expressways or highways. To eliminate congestion and bring in transparency in revenue collection at toll road, this paper proposed an integrated wireless system using five dielectric resonator antennas offering different services for the efficient way of toll collection. Antennas for roadside service, GPS, Wi-Fi and satellite service have been designed to facilitate vehicles and toll authorities. This system is proposed for efficient fare collection depending on the actual distance travelled by the vehicle. This paper has proposed five thermoset microwave material of 12.8 dielectric constant dielectric resonator antennas (DRAs) using hardware prototyped and simulated models, integrated Z-shape cavity (air) for introducing right-hand circular polarization and left-hand circular polarization as novel features, beam steering using three slots with shorting pins. Measured, simulated and theoretical results have been found to be perfectly matching in the proposed DRAs. The beam steering is another novel feature, which is obtained due to structure of DRA by altering positions of ground plane slots. The proposed solution involves utilizing a machine learning model for toll collection, leveraging vehicle images captured during the transaction, and calculating the distance travelled using GPS data.

Every new storage tank in the oil sector is required to be calibrated before using them for oil storage and also to be re-calibrated as statutorily required. Depending on the prevailing regulatory guidelines in the country, either a wet or geometrical method of calibration is adopted. This study examines various geometrical methods of tank calibration vis–a–vis their strengths and weaknesses. Tank farm owners (operators) are always faced with the challenge of selecting the best geometrical method of tank calibration while considering some number of factors. To address this aforementioned issue, this study was embarked upon to rank the known four (4) geometrical methods of tank calibration using Fuzzy TOPSIS (F-TOPSIS) approach. Three different experts were drawn from reputable calibration companies to respond to the questionnaire based on the following criteria: Accuracy; Hazard involved; Time consumed; Drudgery involved; and Cost. The interdependencies among the criteria were considered, and a triangular fuzzy set was adopted. The results revealed that the Electro-Optical Distance Ranging (EODR) is the best alternative with a closeness coefficient of 0.974, while the Optical Reference Line Method was ranked least with a closeness coefficient of 0.197. To validate the result of rating by F-TOPSIS, another hybrid MCDM, Fuzzy Analytic Hierarchy Process (FAHP) was used to rank the alternatives, and EODR was also ranked as the best alternative. Sensitivity analysis was carried out for five different scenarios to validate the robustness of the decision-making tool used in this study. All the scenarios considered for the sensitivity analysis ranked EODR and OTM (Optical Triangulation Method) first and second, respectively. So, it can be concluded that EODR is the best geometrical method of tank calibration. Though the cost of using EODR might be higher than other methods, this is being compensated for by higher accuracy, less time with less exposure to hazards. It can also be confirmed that F-TOPSIS is a formidable MCDM tool that finds its usage in every facet of life for a robust decision-making process.

Multifaceted coatings are in high demand due to their remarkable tribological advantages and fortification from harsh environments. However, ceramics coatings perform well and offer excellent performance but are limited to high temperatures. In the present study, it is perceived that 0.1 wt% nanodiamonds and 1 wt% graphene nanoplatelets reinforced in Al₂O₃ offered improved wear-resisting properties at high temperatures from 300 to 500 °C. The measured relative density recorded was 94.45 ± 1.9, 95.45 ± 0.9, and 97.25 ± 1.9 for A-SD, AND-SD and ANDG-SD, respectively. The wear rate decrement on 10N, at 300 °C, of AND-SD was recorded at 50.12% and 74.50% in ANDG-SD. On 15N, at 400 °C, 48.35% for AND-SD and 64.31% for ANDG-SD were recorded. The highest wear rate reduction, i.e., 74.66%, was recorded in ANDG-SD at 500 °C. The COF value at an applied load of 10N at 300 °C was 0.49, 0.46, and 0.30 for A-SD, AND-SD, and ANDG-SD, respectively. At an applied load of 15N, at 400 °C, it was 0.51 for A-SD, 0.42 for AND-SD, and 0.29 for ANDG-SD. At an applied load of 20N, at 500 °C, 0.54 for A-SD, 0.40 for ANDG-SD, and 0.24 for ANDG-SD were recorded. The maximum decrement in COF value was observed at an applied load of 20N, at 500 °C, due to GNP’s self-lubricating properties, which have the exceptional caliber to enhance wear resistance. Through this study, it has been supposed that developed hybrid coatings could be a robust path for developing coatings at high working temperatures.

To effectively solve the problem that the measurement uncertainty evaluation result is not accurate and the calculation is complicated when the humidity measuring instrument is calibrated. The “Monte Carlo simulation method” (MCM) was proposed to evaluate the measurement uncertainty of humidity sensor calibration results. In this process, firstly, by analyzing the calibration process of humidity sensor, the measurement model that can accurately and completely reflect the actual measurement situation is constructed; then, design a performance testing method for the humidity generator to obtain parameter data that can truly reflect the performance of the current humidity generator; finally, taking the 55%RH calibration point as an example, by using the above measurement model and related parameters, single MCM method and adaptive MCM method were used to evaluate the measurement uncertainty of the humidity sensor calibration results. The evaluation results obtained are the same as: the best estimated value of humidity sensor measurement error ΔH = 0.01%RH, the standard uncertainty u(ΔH) = 0.14%RH, and the shortest coverage interval [ΔH_low, ΔH_high] = [− 0.24%RH, 0.26%RH] when the coverage probability is 95%. Through this application experiment on the MCM method, it was found that compared to the GUM method, the MCM method can effectively improve the credibility of the measurement uncertainty results of the humidity sensor. Moreover, when the adaptive MCM method is applied to evaluate the measurement uncertainty of the humidity sensor, compared to the single MCM method, it can effectively reduce simulation times, reduce storage space resources, and improve evaluation efficiency. Prioritizing the adaptive MCM method in practical operation is recommended.

The pendant drop tensiometry is a preferred primary method for measuring interfacial tension (IFT) or surface tension. In a typical experimental setup, Gravitational pull opposes an interfacial tension forces to cause a liquid drop to develop into a pendant-like shape. The process comprises quantitatively modifying a theoretical profile generated through calculating the Young–Laplace capillarity formula to such an experimental pendant drop analysis and information by performing digital image analysis. However, specific parameters of this method lead to uncertainty in the obtained value of IFT. The present work aims to determine the role of factors such as evaporation of the hanging drop and its changing volume in interfacial tension, which is acting as major source of error in determining IFT of distilled water. This study details the measurement process and evaluation of standard errors with interfacial tension readings of distilled water by using pendant drop method with three calibrated needles of diameters, 0.9 mm (20 G), 1.27 mm (18 G) and 1.65 (16 G) mm. The needle’s diameter influenced the evaporation rate and the value of IFT. Also, it is essential to consider these factors for further evaluating measurement uncertainties when determining the IFT of biological fluids. In addition, the present study makes an effort to determine the measurement error associated with drop volume and evaporation rate of drop in study. The distilled water used in the measurement had an absolute Interfacial tension of 72 mN/m, and the enlarged measurement errors were predicted to be in the range of 0.4–0.6%. It is critical to consider these associated measurement errors when determining the IFT of liquids for metrological application such as establishing primary standards for measurement pertaining to biological fluids.

As a consequence of the exponential increase in energy usage within urban areas, rooftop micro wind turbines have surfaced as a potent method to supply sustainable energy while also strategically mitigating the environmental impact of carbon emissions. However, significant knowledge gaps exist regarding how to install a rooftop micro wind turbine in conjunction with an exhaust fan in a tall building. The objective of this study is to fabricate an exhaust fan cum micro wind turbine (EFCMWT). It is used as an exhaust fan as well as a micro wind turbine. There are various components of EFCMWT, and their dimensions are also discussed in this article. The main components are one-way bearings and couplings, both of which are used to connect dual shaft AC motors and DC generators. For demonstration research, the EFCMWT was placed at the height of 14.111 m on the windows of Kosi Hostel Building, NIT Patna. When the wind speed is 7 m/s, the wind turbine produces a maximum power output of 1.2167 watts and a maximum power coefficient of 0.1247. An exhaust fan cum micro wind turbine can make a significant contribution to reducing the environmental carbon footprint.

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