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This research article introduces a design of a meander line incorporated L-band microstrip patch antenna aimed at reducing its size and volume while enhancing its performance characteristics. The proposed design, furthermore is optimized using popular machine learning techniques. The initial simulation presents a conventional rectangular patch antenna characterized by a gain of 2.23 dB and a resonant frequency of 1.38 GHz, with an impedance bandwidth of 20 MHz. The specified dimensions of this design are 150 × 150 × 1.6 mm³. This study aims to develop a smaller prototype antenna by incorporating symmetric slots and meandering lines into the patch structure. Consequently, the overall dimensions of the prototype are reduced to 40 × 45 × 1.6 mm³, resulting in an impressive volume reduction of 92%. Furthermore, this innovative design yields a substantial increase in bandwidth of 300% and a gain enhancement of 124%, while maintaining the original resonant frequency i.e. 1.38 GHz. Then, four popular machine learning techniques namely Regression Trees, Support Vector Machines under Regression Model (SVR), Kernel Least Squares, and Artificial Neural Networks using Bayesian optimization are compared for antenna parameter optimization. It is observed that the incorporation of different machine-learning approaches in parameter optimization allows us to evaluate potential calculation errors and provide comparatively accurate results.

Recent advancements in novel radio frequency (RF) microwave phase measurement techniques have generated significant interest. Accurate phase measurement is essential for optimal performance in various applications, including telecommunications, radars, phased array antennas, phase modulators, and GPS receivers. High-precision phase measurement methods are crucial for monitoring subtle phase shift variations accurately. This paper analyzes recent research on microwave relative phase measurement techniques based on homodyne and heterodyne detection principles and the associated challenges related to uncertainty, as utilized by national metrology institutes (NMIs). Under the homodyne principle, the National Institute of Standards and Technology (NIST) measured a single phase based on a bridge circuit at 100° with a phase accuracy of 0.5° at a frequency of 4 GHz. This principle is extended by the National Laboratory for Infrared Physics in Japan to measure phase in the range of 0° to 180° in the X-band with a phase accuracy of 2°. Under the heterodyne principle, NIST also implemented phase measurements using a dual-channel phase-shift measurement system from 0° to 360° with an expanded uncertainty of 0.041º at 17 GHz. Several developments in this principle were introduced to address errors and complexity. In addition, a new innovative phase detection methodology based on power measurements was developed by the National Institute of Standards (NIS) in Egypt. This technique offers precise measurements of relative phase shifts in the range from 0° to 180° with a maximum phase variation of ± 3.5°, covering S and C bands. This review aims to contribute to advancing microwave relative phase measurement techniques and provide insights into alternative methods for improvement.

In recent years, the identification of fluid density and viscosity has gained substantial significance across a wide range of industries and scientific fields. These parameters are of utmost importance in comprehending fluid behaviors as accurate measurement of these properties is essential for quality control, process optimization, and product development. A variety of traditional approaches, including capillary, falling ball, volumetry, isochoric, hydrostatic weighing, buoyancy methods, etc., are employed to measure viscosity and density. These traditional approaches require a large amount of samples for measurement and are time consuming. Many modern approaches with different sensing principles have been introduced to overcome the drawbacks of traditional methods. This paper comprehensively describes the densitometers, and viscometers on the basis of different sensing principles such as cantilever, acoustic, tuning fork, diaphragm, pressure, magnetic field, etc. Furthermore, specifications of viscometers and densitometers are briefly summarized, which include the working mechanism, sample range, sample volume, resolution/sensitivity, accuracy/error, testing sample, and temperature. Through this, a mass insight into viscosity and density measurements can be found for wide range of liquids/gas across diverse applications including biopharmaceuticals, protein therapeutics, lubricants, adhesives, healthcare, food production, cosmetics, construction, paints, as well as fuel and petroleum.

Advancement in artificial intelligence and internet of things has driven short-range connectivity to a different level which eases human life. This has connected each and every house use appliances, electronic gadgets, and wearable devices via Bluetooth or WiFi and facility to control them via voice command or app-based systems. This advancement leads to a complex RF coexistence, interference, and exposure assessment to an essential evaluation. This paper reviews the existing electromagnetic compatibility (EMC) and electromagnetic interference assessment methods as per EMC standards for radiation emission and susceptibility requirements. In this direction, EM field measurement methods are reviewed spanning-open area test site, anechoic chamber, transverse electromagnetic cell, compact antenna test range, reverberation chamber, and near field scanning techniques. Each technique for EM field measurement proves to be application-driven and beneficial in many scientific aspects.

Real-time monitoring of the cutting force during the cutting process is crucial. In the past, cutting force sensors of various structures have been developed, and to improve the integrality and reduce the cross-interference error, a double-parallel-beam cutting force sensor is designed in this study. Through theoretical analysis and finite element method to analyze the influence of each factor on the performance of the sensor, to determine the optimal parameters of the sensor, to fabricate the prototype, and to carry out the patch, group bridge, and package on the double parallel beam. Then the performance test is carried out, and the results show that the sensitivities of the double parallel beam cutting force sensor in the two directions of main cutting force F_c and feed force F_f are 4.11 × 10⁻³ mV/N and 4.75 × 10⁻³ mV/N, respectively, and the minimum cross-interference error is only 0.88%; finally, the cutting test is carried out, and the designed cutting force sensor exhibits a satisfactory ability to accurately measure and record the cutting force under different cutting parameters.

The study of time scale facilitates stable and reliable operation of time-keeping systems. Algos algorithm is a common method for calculating the time scale. Improving the stability of the time scale is an important issue in the research of time-keeping technology. In this paper, an optimization method of the clock difference data preprocessing in algorithm is proposed. We apply the theory of optimal weight to the calculation of time scale weight for improving the stability of the dynamic time scale. The proposed algorithm is called Improved Dynamic Algos-like (IDAlgos). We use the IDAlgos for joint experiments of cesium clocks ensemble, hydrogen masers ensemble, and hydrogen-cesium clocks ensemble, respectively. The results compared with Conventional Dynamic Algos-like (CDAlgos) show that i) for the case of cesium clocks ensemble, the short-term stability has been improved, the stability increased by 22.5% in 2 h and 20.8% in 4 h. ii) for the case of hydrogen masers ensemble, the stability increased by 18.3% in 1 h and 31.3% in 128 h, that is, both long-term and short-term stability has been improved. iii) for the clock ensemble combined of hydrogen masers and cesium clocks, the long-term and short-term stability has been greatly improved,among them, the stability increased by 64.6% in 1 h and 69.3% in 128 h. Consequently, the IDAlgos has obvious improving on the stability of the time scale

This study presents the design and evaluation of wind tunnel performance at the National Institute of Standards in Egypt. Flow contraction in the convergent nozzle of a subsonic wind tunnel is one of the most effective means of reducing the level of turbulence intensity in the testing section. Accordingly, this study is based on designing a contraction ratio of 7, and comparing this ratio with previous studies in terms of turbulence intensity. The construction steps for the major components of the wind tunnel and calibration procedure are described. The calibration results show that the present wind tunnel provides a good repeatability of ± 0.003 m/s. In addition, reproducibility conditions provide a high confidence level in the results obtained from long-term investigations, with satisfactory performance. The results of the experimental study on the influence of flow contraction on the mean turbulence intensity in the convergence nozzle of an open-loop subsonic wind tunnel were less than 0.5%. In addition, the accuracy and stability of the wind tunnel design were verified using statistical evaluation of the normalized error value (En-value). The results indicate that the maximum normalized error of the measurement at the end of the test section was 0.8.

Electrical metrology is a discipline that aims to guarantee the accuracy, precision, and dependability of electrical systems and apparatuses. Any departure from the necessary measuring standards can significantly impact the operation of electrical systems and devices. Thus, it is crucial to develop cutting-edge calibration techniques to increase the precision and effectiveness of electrical measurements, i.e., the dependability of electrical measurements, while saving time and resources. One of the calibration techniques utilizes visual guidance while calibrating, which is helpful for junior metrologists who lack expertise and training. This technique incorporates virtual standards in electrical metrology, which can increase accuracy and efficiency and provide visual guidance. This paper proposes the adoption of extended reality as an immersive measurement tool to overcome obstacles and improve the accuracy and efficiency of metrology. Electrical instruments can be precisely calibrated in a virtual environment by replacing real standards with virtual standards. This could be achieved through the adoption of extended reality technologies like virtual reality, augmented reality, and mixed reality, all of which give metrologists an immersive and engaging experience, allowing them to test and improve their performance via immersive metrology. Such immersive metrology can aid in the improvement of metrologists’ training by enabling them to obtain practical experience in a virtual setting that is risk-free and secure before experiencing measurement methods in realistic experimental settings.

This study examines the efficacy of interlaboratory comparison tests in evaluating the calibration of analogue bimetal thermometers and dry-block calibrators. These instruments play a pivotal role in various industrial applications involving temperature measurement and calibration. The Turkish Standards Institution (TSE) organized a bilateral interlaboratory comparison with a foreign public authority laboratory, focusing on the calibration of a dry-block calibrator and an analogue bimetal thermometer. Interlaboratory comparison tests are expected to reveal consistent calibration results with E_n values less than one, signifying comparable calibration outcomes across different laboratories. While measurement uncertainties may vary between laboratories, these differences are anticipated to remain within acceptable limits as defined by international standards. Participation in interlaboratory comparison tests enhances the technical competencies of laboratories, particularly in calibration accuracy and uncertainty management.

The up-surging of environmental, economic, and social-related matters has changed the view of corporate stakeholders' responsiveness towards profit. They have started thinking about the planet, people, and their wealth besides profit. Consequently, high hope is also focused on Environmental, Social And Governance (ESG) factors. The commitment towards the environment and social responsibility of the organization imitates the ESG performance of enterprises that are corporating ESG activities in their working style with a vigorous governance structure; furthermore, the Covid pandemic has exaggerated the importance of ESG parameters. Corporate stakeholders are fervent in knowing how ESG practices can be embraced into business policy, bringing more clarity and transparency to ESG reporting disclosures. The present study offers insight into the ESG concerns unfolding in terms of their prominence and the existing situation in India. In this study, we briefly discuss the need for ESG in Indian organizations and its transformation landscape for the future. Then, we discuss ESG adoption preparedness and its challenges in India. Then, we discussed the steps to be taken to achieve the aim of the sustainability strategy and its implementation, including the ESG Strategy, its linkage of ESG with GHG protocol with measurable metrology tools & the role of metrology in measuring Scope-1, Scope-2, and Scope-3 its emissions measurement with metrology measuring instruments. In the next section, we discuss the need for sustainable ESG reporting, its associated trends and challenges, and India's current status in ESG funds, ESG investing, and its current challenges.