Journal Description
Metrology
Metrology
is an international, peer-reviewed, open access journal on the science and technology of measurement and metrology, published quarterly online by MDPI.
- Open Access— free for readers, with article processing charges (APC) paid by authors or their institutions.
- Rapid Publication: manuscripts are peer-reviewed and a first decision is provided to authors approximately 28.6 days after submission; acceptance to publication is undertaken in 5.2 days (median values for papers published in this journal in the second half of 2023).
- Recognition of Reviewers: APC discount vouchers, optional signed peer review, and reviewer names published annually in the journal.
Latest Articles
Analyzing Power Law Extensions of Newtonian Gravity Using Differential Force Measurements
Metrology 2024, 4(2), 227-239; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology4020014 - 18 Apr 2024
Abstract
►
Show Figures
The Standard Model is not a complete description of reality; it omits the existence of dark matter, dark energy, and an explanation as to why no CP violation has been observed. However, some of these phenomena could be explained through a new force
[...] Read more.
The Standard Model is not a complete description of reality; it omits the existence of dark matter, dark energy, and an explanation as to why no CP violation has been observed. However, some of these phenomena could be explained through a new force mediated by a new boson. If such a boson were massless it would result in a power law potential and if massive the interaction would be Yukawa-like. A previous experiment employing the interactions of a micromechanical oscillator attached to spherical test mass was successful in placing the best limits on a mass–mass Yukawa-like interaction, but the data were never analyzed in the context of a power law. Here, those data are analyzed considering a power law for powers n = 1–5 where n is the number of boson exchanges. The results show that the limits obtained through power law analysis of these data are not better than the currently accepted limits. A discussion of an experiment design capable of producing better limits on power law extensions to the Standard Model is presented, and suggests that a micromechanical-oscillator-based experiment remains capable of improving the limits by at least one order of magnitude.
Full article
Open AccessArticle
Comparison of Dimensional Accuracy between a Laser Scanner and a Laser Tracker with Handheld Scan in a Laboratory Setting
by
Alex Krummenauer, Douglas Bergamo, Roberto Serpa Soares, Victor Emmanuel de Oliveira Gomes and Vitor Camargo Nardelli
Metrology 2024, 4(2), 205-226; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology4020013 - 12 Apr 2024
Abstract
The dimensional accuracy of a laser scanner has been extensively evaluated using various measurement methods and diverse reference standards. This study specifically focuses on two key considerations. Firstly, it assesses the dimensional accuracy of the laser scanner by employing another laser scanner, a
[...] Read more.
The dimensional accuracy of a laser scanner has been extensively evaluated using various measurement methods and diverse reference standards. This study specifically focuses on two key considerations. Firstly, it assesses the dimensional accuracy of the laser scanner by employing another laser scanner, a handheld scanner, as the reference measurement method. Secondly, the study involves the use of three spheres fixed on each wall in both coplanar and non-coplanar positions within a laboratory room at SENAI ISI-SIM. The primary objective is to determine the dimensional accuracy between the centers of the coplanar and non-coplanar spheres up to 10 m. The comparison includes measurement uncertainties, as per ISO GUM standards, obtained using the laser scanner in a laboratory setting with controlled temperature and humidity. Analyzing non-coplanar dimensional accuracy enhances our understanding of the metrological performance of the laser scanner, particularly when assessing the dimensions of objects positioned randomly within a scanning scene.
Full article
(This article belongs to the Special Issue Advances in Laser Interferometry for Precision Engineering)
►▼
Show Figures
Figure 1
Open AccessReview
Combined Use of Acoustic Measurement Techniques with X-ray Imaging for Real-Time Observation of Laser-Based Manufacturing
by
Mahdieh Samimi, Mehran Saadabadi and Hassan Hosseinlaghab
Metrology 2024, 4(2), 181-204; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology4020012 - 08 Apr 2024
Abstract
Ensuring high-quality control in laser additive manufacturing and laser welding relies on the implementation of reliable and cost-effective real-time observation techniques. Real-time monitoring techniques play an important role in understanding critical physical phenomena, namely, melt pool dynamics and defect formation, during the manufacturing
[...] Read more.
Ensuring high-quality control in laser additive manufacturing and laser welding relies on the implementation of reliable and cost-effective real-time observation techniques. Real-time monitoring techniques play an important role in understanding critical physical phenomena, namely, melt pool dynamics and defect formation, during the manufacturing of components. This review aims to explore the integration of acoustic measurement techniques with X-ray imaging for studying these physical phenomena in laser manufacturing. A key aspect emphasized in this work is the importance of time synchronization for real-time observation using multiple sensors. X-ray imaging has proven to be a powerful tool for observing the dynamics of the melt pools and the formation of defects in real time. However, X-ray imaging has limitations in terms of accessibility which can be overcome through combination with other more-accessible measurement methods, such as acoustic emission spectroscopy. Furthermore, this combination simplifies the interpretation of acoustic data, which can be complex in its own right. This combined approach, which has evolved in recent years, presents a promising strategy for understanding acoustic emission signals during laser processing. This work provides a comprehensive review of existing research efforts in this area.
Full article
(This article belongs to the Special Issue Novel Dynamic Measurement Methods and Systems)
►▼
Show Figures
Figure 1
Open AccessArticle
Impact of Angular Speed Calculation Methods from Encoder Measurements on the Test Uncertainty of Electric Motor Efficiency
by
João P. Z. Machado, Gabriel Thaler, Antonio L. S. Pacheco and Rodolfo C. C. Flesch
Metrology 2024, 4(2), 164-180; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology4020011 - 02 Apr 2024
Abstract
The imperative need to advance the development of more efficient electric motors requires the meticulous measurement of small increments while minimizing the associated uncertainty in dynamometer tests. One of the key variables in such tests is the angular speed, which is typically obtained
[...] Read more.
The imperative need to advance the development of more efficient electric motors requires the meticulous measurement of small increments while minimizing the associated uncertainty in dynamometer tests. One of the key variables in such tests is the angular speed, which is typically obtained based on encoder measurements. This paper proposes a systematic measurement uncertainty assessment method based on the Guide to the Expression of Uncertainty for the two most widely used methods for angular speed measurement, namely, the frequency and period methods. In addition, the impact of the angular speed calculation method on the efficiency test uncertainty is assessed using an automatic test rig for electric motors. Our experimental results consider both steady-state and dynamic analyses. The results show that the period measurement method provides measurements with lower uncertainty for the encoders typically used in such test rigs, about 30 times less than the uncertainty determined for the frequency measurement method. Based on these results, the choice of a proper method can drastically decrease the angular speed uncertainty, and consequently the motor efficiency uncertainty, without increasing instrumentation cost.
Full article
(This article belongs to the Collection Measurement Uncertainty)
►▼
Show Figures
Figure 1
Open AccessArticle
Statistical Analysis of Measurement Processes Using Multi-Physic Instruments: Insights from Stitched Maps
by
Clement Moreau, Julie Lemesle, David Páez Margarit, François Blateyron and Maxence Bigerelle
Metrology 2024, 4(2), 141-163; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology4020010 - 26 Mar 2024
Abstract
Stitching methods allow one to measure a wider surface without the loss of resolution. The observation of small details with a better topographical representation is thus possible. However, it is not excluded that stitching methods generate some errors or aberrations on topography reconstruction.
[...] Read more.
Stitching methods allow one to measure a wider surface without the loss of resolution. The observation of small details with a better topographical representation is thus possible. However, it is not excluded that stitching methods generate some errors or aberrations on topography reconstruction. A device including confocal microscopy (CM), focus variation (FV), and coherence scanning interferometry (CSI) instrument modes was used to chronologically follow the drifts and the repositioning errors on stitching topographies. According to a complex measurement plan, a wide measurement campaign was performed on TA6V specimens that were ground with two neighboring SiC FEPA grit papers (P#80 and P#120). Thanks to four indicators (quality, drift, stability, and relevance indexes), no measurement drift in the system was found, indicating controlled stitching and repositioning processes for interferometry, confocal microscopy, and focus variation. Measurements show commendable stability, with interferometric microscopy being the most robust, followed by confocal microscopy, and then focus variation. Despite variations, robustness remains constant for each grinding grit, minimizing interpretation biases. A bootstrap analysis reveals time-dependent robustness for confocal microscopy, which is potentially linked to human presence. Despite Sa value discrepancies, all three metrologies consistently discriminate between grinding grits, highlighting the reliability of the proposed methodology.
Full article
(This article belongs to the Collection Measurement Uncertainty)
►▼
Show Figures
Figure 1
Open AccessArticle
Error Analysis of an Economical On-Site Calibration System for Linear Optical Encoders
by
Yatao Huang, Zihan Su, Di Chang, Yunke Sun and Jiubin Tan
Metrology 2024, 4(1), 131-140; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology4010009 - 13 Mar 2024
Abstract
A calibration system was designed to evaluate the accuracy of linear optical encoders at the micron level in a fast and economical manner. The system uses a commercial interferometer and motor stage as the calibrator and moving platform. Error analysis is necessary to
[...] Read more.
A calibration system was designed to evaluate the accuracy of linear optical encoders at the micron level in a fast and economical manner. The system uses a commercial interferometer and motor stage as the calibrator and moving platform. Error analysis is necessary to prove the effectiveness and identify areas for optimization. A fixture was designed for the scale and interferometer target to meet the Abbe principle. A five-degree-of-freedom manual stage was utilized to adjust the reading head in optimal or suboptimal working conditions, such as working distance, offset, and angular misalignment. The results indicate that the calibration system has an accuracy of ±2.2 μm. The geometric errors of the calibration system, including mounting errors and non-ideal motions, are analyzed in detail. The system could be an inexpensive solution for encoder manufacturers and customers to calibrate a linear optical encoder or test its performance.
Full article
(This article belongs to the Special Issue Advances in Laser Interferometry for Precision Engineering)
►▼
Show Figures
Figure 1
Open AccessArticle
Study of the Errors in Interpolated Fast Fourier Transform for Interferometric Applications
by
Federico Cavedo, Parisa Esmaili and Michele Norgia
Metrology 2024, 4(1), 117-130; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology4010008 - 08 Mar 2024
Abstract
Frequency estimation is often the basis of various measurement techniques, among which optical distance measurement stands out. One of the most used techniques is interpolated fast Fourier transform due to its simplicity, combined with good performance. In this work, we study the limits
[...] Read more.
Frequency estimation is often the basis of various measurement techniques, among which optical distance measurement stands out. One of the most used techniques is interpolated fast Fourier transform due to its simplicity, combined with good performance. In this work, we study the limits of this technique in the case of real signals, with reference to a particular interferometric technique known as self-mixing interferometry. The aim of this research is the better understanding of frequency estimation performances in real applications, together with guidance on how to improve them in specific optical measurement techniques. An optical rangefinder, based on self-mixing interferometry, has been realized and characterized. The simulation results allow us to explain the limits of the interpolated fast Fourier transform applied to the realized instrument. Finally, a method for overcoming them is proposed by decorrelating the errors between the measurements, which can provide a guideline for the design of frequency-modulated interferometric distance meters.
Full article
(This article belongs to the Special Issue Advances in Laser Interferometry for Precision Engineering)
►▼
Show Figures
Figure 1
Open AccessArticle
A 10 V Transfer Standard Based on Low-Noise Solid-State Zener Voltage Reference ADR1000
by
André Bülau, Daniela Walter and André Zimmermann
Metrology 2024, 4(1), 98-116; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology4010007 - 05 Mar 2024
Abstract
►▼
Show Figures
Voltage standards are widely used to transfer volts from Josephson voltage standards (JVSs) at national metrology institutes (NMIs) into calibration labs to maintain the volts and to transfer them to test equipment at production lines. Therefore, commercial voltage standards based on Zener diodes
[...] Read more.
Voltage standards are widely used to transfer volts from Josephson voltage standards (JVSs) at national metrology institutes (NMIs) into calibration labs to maintain the volts and to transfer them to test equipment at production lines. Therefore, commercial voltage standards based on Zener diodes are used. Analog Devices Inc. (San Jose, CA, USA), namely, Eric Modica, introduced the ADR1000KHZ, a successor to the legendary LTZ1000, at the Metrology Meeting 2021. The first production samples were already available prior to this event. In this article, this new temperature-stabilized Zener diode is compared to several others as per datasheet specifications. Motivated by the superior parameters, a 10 V transfer standard prototype for laboratory use with commercial off-the-shelf components such as resistor networks and chopper amplifiers was built. How much effort it takes to reach the given parameters was investigated. This paper describes how the reference was set up to operate it at its zero-temperature coefficient (z.t.c.) temperature and to lower the requirements for the oven stability. Furthermore, it is shown how the overall temperature coefficient (t.c.) of the circuit was reduced. For the buffered Zener voltage, a t.c. of almost zero, and with amplification to 10 V, a t.c. of <0.01 µV/V/K was achieved in a temperature span of 15 to 31 °C. For the buffered Zener voltage, a noise of ~584 nVp-p and for the 10 V output, ~805 nVp-p were obtained. Finally, 850 days of drift data were taken by comparing the transfer standard prototype to two Fluke 7000 voltage standards according to the method described in NBS Technical Note 430. The drift specification was, however, not met.
Full article
Figure 1
Open AccessArticle
Foam Pressure Mapping with Optimized Electrodes
by
Jake Sundet, Jake Merrell, Maxwell Tree, Trevor Christensen and Stephen Schultz
Metrology 2024, 4(1), 82-97; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology4010006 - 07 Feb 2024
Abstract
Nano-composite piezo-responsive foam (NCPF) is an inexpensive foam that can be used to measure a static load while still providing a comfortable interface. The purpose of this study was to create a modularized foam-based pressure measurement system. A measurement system was developed that
[...] Read more.
Nano-composite piezo-responsive foam (NCPF) is an inexpensive foam that can be used to measure a static load while still providing a comfortable interface. The purpose of this study was to create a modularized foam-based pressure measurement system. A measurement system was developed that uses an interdigitated electrode applied to the NCPF. Applied pressure changes the impedance of the NCPF, which, in turn, is converted into a voltage using a voltage divider. A modular measurement system is described that uses an ATtiny 1627 microcontroller to measure the pressure at nine electrodes. The nine electrode modules are controlled by an ESP32 microcontroller that aggregates the data and wirelessly transmits the data to a tablet. The modular system was demonstrated with 1008 individual electrodes. The characterization of the electrode combined with the NCPF is presented, along with optimization of the electrode geometry.
Full article
(This article belongs to the Special Issue Next-Level Surface Metrology—Advances in Sensors, Data Analysis and Simulation)
►▼
Show Figures
Figure 1
Open AccessArticle
Deep Learning for Concrete Crack Detection and Measurement
by
Mthabisi Adriano Nyathi, Jiping Bai and Ian David Wilson
Metrology 2024, 4(1), 66-81; https://doi.org/10.3390/metrology4010005 - 05 Feb 2024
Abstract
Concrete structures inevitably experience cracking, which is a common form of damage. If cracks are left undetected and allowed to worsen, catastrophic failures, with costly implications for human life and the economy, can occur. Traditional image processing techniques for crack detection and measurement
[...] Read more.
Concrete structures inevitably experience cracking, which is a common form of damage. If cracks are left undetected and allowed to worsen, catastrophic failures, with costly implications for human life and the economy, can occur. Traditional image processing techniques for crack detection and measurement have several limitations, which include complex parameter selection and restriction to measuring cracks in pixels, rather than more practical units of millimetres. This paper presents a three-stage approach that utilises deep learning and image processing for crack classification, segmentation and measurement. In the first two stages, custom CNN and U-Net models were employed for crack classification and segmentation. The final stage involved measuring crack width in millimetres by using a novel laser calibration method. The classification and segmentation models achieved 99.22% and 96.54% accuracy, respectively, while the mean absolute error observed for crack width measurement was 0.16 mm. The results demonstrate the adequacy of the developed crack detection and measurement method, and shows the developed deep learning and laser calibration method promotes safer, quicker inspections that are less prone to human error. The method’s ability to measure cracks in millimetres provides a more insightful assessment of structural damage, which is, in comparison to traditional pixel-based measurement methods, a significant improvement for practical field applications.
Full article
(This article belongs to the Special Issue Novel Dynamic Measurement Methods and Systems)
►▼
Show Figures
Figure 1
Open AccessArticle
Experimental Investigation on the Transfer Behavior and Environmental Influences of Low-Noise Integrated Electronic Piezoelectric Acceleration Sensors
by
Jan-Hauke Bartels, Ronghua Xu, Chongjie Kang, Ralf Herrmann and Steffen Marx
Metrology 2024, 4(1), 46-65; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology4010004 - 01 Feb 2024
Abstract
►▼
Show Figures
Acceleration sensors are vital for assessing engineering structures by measuring properties like natural frequencies. In practice, engineering structures often have low natural frequencies and face harsh environmental conditions. Understanding sensor behavior on such structures is crucial for reliable measurements. The research focus is
[...] Read more.
Acceleration sensors are vital for assessing engineering structures by measuring properties like natural frequencies. In practice, engineering structures often have low natural frequencies and face harsh environmental conditions. Understanding sensor behavior on such structures is crucial for reliable measurements. The research focus is on understanding the behavior of acceleration sensors in harsh environmental conditions within the low-frequency acceleration range. The main question is how to distinguish sensor behavior from structural influences to minimize errors in assessing engineering structure conditions. To investigate this, the sensors are tested using a long-stroke calibration unit under varying temperature and humidity conditions. Additionally, a mini-monitoring system configured with four IEPE sensors is applied to a small-scale support structure within a climate chamber. For the evaluation, a signal-energy approach is employed to distinguish sensor behavior from structural behavior. The findings show that IEPE sensors display temperature-dependent nonlinear transmission behavior within the low-frequency acceleration range, with humidity having negligible impact. To ensure accurate engineering structure assessment, it is crucial to separate sensor behavior from structural influences using signal energy in the time domain. This study underscores the need to compensate for systematic effects, preventing the underestimation of vibration energy at low temperatures and overestimation at higher temperatures when using IEPE sensors for engineering structure monitoring.
Full article
Figure 1
Open AccessArticle
Conservation Voltage Reduction Impact Investigation for Personal Computing Devices Using Experimental Measurements and Computation Performance Metrics
by
Muhammad Ayaz, Syed Muhammad Hur Rizvi and Muhammad Akbar
Metrology 2024, 4(1), 24-45; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology4010003 - 16 Jan 2024
Abstract
►▼
Show Figures
Conservation Voltage Reduction (CVR) is a potential energy management approach for increasing computer system energy efficiency. This study uniquely contributes to the field by thoroughly investigating the impact of CVR on computing devices, filling a significant gap in the existing literature. The research
[...] Read more.
Conservation Voltage Reduction (CVR) is a potential energy management approach for increasing computer system energy efficiency. This study uniquely contributes to the field by thoroughly investigating the impact of CVR on computing devices, filling a significant gap in the existing literature. The research employs a novel experimental approach, considering the temporal variations in energy use behavior, and presents a comprehensive benchmark analysis of desktop PCs and laptops. Notable gains in processing efficiency are observed, with specific instances such as Desktop 1’s 1.53% Single-Core performance improvement and Desktop 3’s 3.19% total performance boost. Despite variations, the thermal performance of CVR-equipped devices, particularly Desktop 3 and Laptop 3, consistently demonstrates lower temperatures, indicating thermal management enhanced by 3.19% and 1.35%, respectively. Additionally, the study introduces the CVR Performance Enhancement Ratio (%), providing a unique metric for evaluating the trade-offs between energy efficiency and system performance. This research highlights the dual impact of CVR on thermal and computational elements, emphasizing its broad advantages. Integrating CVR emerges as a viable strategy for developing more durable, efficient, and sustainable computing devices, setting the stage for advancements in voltage regulation.
Full article
Figure 1
Open AccessCommunication
Design of Experiments for Evaluating the Relevance of Change in Test Method for Kinematic Viscosity of Opaque Oils
by
Mauro Alves Correa de Camargo, Gabriela Knippelberg Bifano Manea and Elcio Cruz de Oliveira
Metrology 2024, 4(1), 15-23; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology4010002 - 05 Jan 2024
Abstract
►▼
Show Figures
Viscosity is a physicochemical property that evaluates the resistance that fuel offers to flow, influencing the engine’s operation and combustion process. Its control is aimed at good fuel atomization and the preservation of lubricating characteristics. Changes in viscosity can lead to wear on
[...] Read more.
Viscosity is a physicochemical property that evaluates the resistance that fuel offers to flow, influencing the engine’s operation and combustion process. Its control is aimed at good fuel atomization and the preservation of lubricating characteristics. Changes in viscosity can lead to wear on various parts of the engine. Viscometers typically measure the viscosity of fuels in the oil and gas industry. These instruments can measure the time it takes for a fluid to move a given distance through a pipe or the time it takes for an object of a given size and density to pass through the liquid. The traditional test method, ASTM D445, differentiates the procedure for opaque liquids from transparent ones; that is, it requires a warm-up of the sample between 60 °C and 65 °C for 1 h. This additional step can overload laboratory routines, although it is not guaranteed to have a metrologically significant effect on the final result. Thus, this study evaluated the relevance of complying with this step in the test method for the kinematic viscosity of opaque liquids using a 32 factorial experimental design. Based on the F test, p-value, confidence intervals, and percentage contribution of the sum of squares approaches concerning the regression analysis, one concluded that the warm-up time was not a relevant factor in the kinematic viscosity, specifically of very low sulphur fuel oil, Brazilian fuel oil, and atmospheric residue diluted with diesel oil, which are fluids at room temperature.
Full article
Graphical abstract
Open AccessArticle
Digital Impedance Bridge for Four-Terminal-Pair AC Resistor Calibration up to 20 kHz
by
Mohamed Ouameur, Renata Vasconcellos and Mohamed Agazar
Metrology 2024, 4(1), 1-14; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology4010001 - 04 Jan 2024
Abstract
For this study, a substitution principle-based impedance bridge has been developed to calibrate AC resistors in a four-terminal-pair (4TP) configuration. The calibration is performed in the full complex plane for resistances ranging from 100 mΩ to 400 Ω and frequencies of between 50
[...] Read more.
For this study, a substitution principle-based impedance bridge has been developed to calibrate AC resistors in a four-terminal-pair (4TP) configuration. The calibration is performed in the full complex plane for resistances ranging from 100 mΩ to 400 Ω and frequencies of between 50 Hz and 20 kHz. The automated bridge is based on four resistors associated with two high-impedance stages. The balancing of the bridge is achieved by means of PXI modules. The bridge is automatically balanced via a simplex top-down algorithm. The new bridge is primarily used for the measurement chain of AC standard resistors defined in a 4TP configuration at LNE, which are used for routine customer calibrations. The traceability of LNE’s standard resistors when defined in a 4TP configuration is ensured by a measurement chain from a 1 kΩ reference resistor using the new bridge. The reference resistor was calibrated previously via comparison with a calculable resistor up to 20 kHz. The bridge was validated via comparison with calibration results obtained in 1983 and 2009. For a resistor of 1 Ω at 1 kHz, the uncertainty of the series resistance variation and the phase shift are less than 6 µΩ/Ω (k = 1) and 6 µrad (k = 1), respectively.
Full article
(This article belongs to the Special Issue Power and Electronic Measurement Systems)
►▼
Show Figures
Figure 1
Open AccessCommunication
Analysis of the Usefulness of Cheap Audio Recorders for Spectral Measurement of Environmental Noise
by
Jacek Dominik Skibicki, Roksana Licow, Natalia Karosińska-Brzozowska, Karol Daliga, Piotr Chrostowski, Andrzej Wilk, Krzysztof Karwowski, Marek Szafrański, Tadeusz Widerski, Leszek Jarzebowicz, Slawomir Judek, Michał Michna, Sławomir Grulkowski and Julia Omilianowicz
Metrology 2023, 3(4), 381-388; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology3040024 - 12 Dec 2023
Abstract
►▼
Show Figures
Environmental noise pollution is nowadays one of the most serious health threats. The impact of noise on the human body depends not only on the sound level but also on its spectral distribution. Reliable measurements of the environmental noise spectrum are often hampered
[...] Read more.
Environmental noise pollution is nowadays one of the most serious health threats. The impact of noise on the human body depends not only on the sound level but also on its spectral distribution. Reliable measurements of the environmental noise spectrum are often hampered by the very high price of top quality measuring devices. This paper explores the possibility of using much cheaper audio recorders for the frequency analysis. Comparative research was performed in laboratory and field conditions, which showed that, with some limitations, these devices can be useful in analyzing the frequency of environmental noise. This provides an opportunity for reducing the cost of noise analysis experimental work.
Full article
Figure 1
Open AccessEditorial
Editorial for Special Issue: “Advances in Portable 3D Measurement”
by
Stephen Kyle, Stuart Robson and Ben Hughes
Metrology 2023, 3(4), 377-380; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology3040023 - 23 Nov 2023
Abstract
In the context of the journal Metrology, portable 3D measurement is focused on manufacturing applications where there are typically demands for high-accuracy 3D data, with uncertainties in the range of a few 10s of micrometres to a few tenths of millimetres [...]
Full article
(This article belongs to the Special Issue Advances in Portable 3D Measurement)
Open AccessArticle
Spectroscopic Reflectometry for Optimizing 3D Through-Silicon-Vias Process
by
Yi-Sha Ku, Chun-Wei Lo, Cheng-Kang Lee, Chia-Hung Cho, Wen-Qii Cheah and Po-Wen Chou
Metrology 2023, 3(4), 365-376; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology3040022 - 22 Nov 2023
Abstract
►▼
Show Figures
The main challenges in 3D metrology involve measuring TSVs etched with very high aspect ratios, where the via depth to diameter ratio approaches 10:1–20:1. In this paper, we introduce an innovative approach to enhance our in-house spectroscopic reflectometer module by integrating aperture technology,
[...] Read more.
The main challenges in 3D metrology involve measuring TSVs etched with very high aspect ratios, where the via depth to diameter ratio approaches 10:1–20:1. In this paper, we introduce an innovative approach to enhance our in-house spectroscopic reflectometer module by integrating aperture technology, resulting in a substantial amplification of interference signals. Our system offers the flexibility to conduct measurements on an average number of TSVs, individual TSVs, or specific periodic arrays of TSVs. Additionally, we demonstrate the utility of the spectroscopic reflectometer as a non-destructive, high-speed metrology solution for in-line monitoring of TSV etch uniformity. Through a series of experimental trials in a reactive ion etch (RIE) process, we show that leveraging feedback data from the reflectometer leads to marked improvements in etch depth uniformity.
Full article
Figure 1
Open AccessArticle
Predictive Modeling of Photovoltaic Panel Power Production through On-Site Environmental and Electrical Measurements Using Artificial Neural Networks
by
Oscar Lobato-Nostroza, Gerardo Marx Chávez-Campos, Antony Morales-Cervantes, Yvo Marcelo Chiaradia-Masselli, Rafael Lara-Hernández, Adriana del Carmen Téllez-Anguiano and Miguelangel Fraga-Aguilar
Metrology 2023, 3(4), 347-364; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology3040021 - 30 Oct 2023
Abstract
Weather disturbances pose a significant challenge when estimating the energy production of photovoltaic panel systems. Energy production and forecasting models have recently been used to improve energy estimations and maintenance tasks. However, these models often rely on environmental measurements from meteorological units far
[...] Read more.
Weather disturbances pose a significant challenge when estimating the energy production of photovoltaic panel systems. Energy production and forecasting models have recently been used to improve energy estimations and maintenance tasks. However, these models often rely on environmental measurements from meteorological units far from the photovoltaic systems. To enhance the accuracy of the developed model, a measurement Internet of Things (IoT) prototype was developed in this study, which collects on-site voltage and current measurements from the panel, as well as the environmental factors of lighting, temperature, and humidity in the system’s proximity. The measurements were then subjected to correlation analysis, and various artificial neural networks (ANNs) were implemented to develop energy estimations and forecasting models. The most effective model utilizes lighting, temperature, and humidity. The model achieves a root mean squared error (RMSE) of 0.255326464. The ANN models are compared to an MLR model using the same data. Using previous power measurements and actual weather data, a non-autoregressive neural network (Non-AR-NN) model forecasts future output power values. The best Non-AR-NN model produces an RMSE of 0.1160, resulting in accurate predictions based on the IoT device.
Full article
(This article belongs to the Special Issue Power and Electronic Measurement Systems)
►▼
Show Figures
Figure 1
Open AccessArticle
A Two-Dimensional K-Shell X-ray Fluorescence (2D-KXRF) Model for Soft Tissue Attenuation Corrections of Strontium Measurements in a Cortical Lamb Bone Sample
by
Mihai R. Gherase
Metrology 2023, 3(4), 325-346; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology3040020 - 06 Oct 2023
Abstract
►▼
Show Figures
Human bones store elements such as calcium, phosphorus, and strontium, and accumulate toxic elements such as lead. In vivo measurements of elemental bone concentration can be done using X-ray fluorescence (XRF) techniques. Monte Carlo (MC) simulations of X-ray interactions were predominantly employed in
[...] Read more.
Human bones store elements such as calcium, phosphorus, and strontium, and accumulate toxic elements such as lead. In vivo measurements of elemental bone concentration can be done using X-ray fluorescence (XRF) techniques. Monte Carlo (MC) simulations of X-ray interactions were predominantly employed in this field to develop calibration methods that linked XRF measurements to concentrations. A simple and fast two-dimensional K-shell X-ray fluorescence model was developed to compute the KXRF signal of elements in bone and overlying soft tissue samples. The model is an alternative to MC methods and can guide future bone XRF studies. Contours of bone and soft tissue cross sections were elliptical and only KXRF signals from absorption of primary photons were considered. Predictions of the model were compared to Sr KXRF measurements using the bare lamb bone (LB) and the LB with overlying leather. XRF experiments used a small X-ray beam, silicon X-ray detector, and three positioning stages. Linear attenuation coefficients of the leather and LB were measured and used in the model. Measured and model-derived values of the Sr X-rays leather attenuation and Sr Kβ/Kα ratio agreed, but estimated bone Sr concentrations were likely overestimated. Results, approximations, future work directions, and applications were discussed.
Full article
Figure 1
Open AccessConference Report
Report of the CCU/CCQM Workshop on “The Metrology of Quantities Which Can Be Counted”
by
Richard J. C. Brown, Bernd Güttler, Pavel Neyezhmakov, Michael Stock, Robert I. Wielgosz, Stefan Kück and Konstantina Vasilatou
Metrology 2023, 3(3), 309-324; https://0-doi-org.brum.beds.ac.uk/10.3390/metrology3030019 - 04 Sep 2023
Cited by 2
Abstract
This article provides a report of the recent workshop on “The metrology of quantities which can be counted” organised jointly by the International Committee for Weights and Measures’ Consultative Committees for Amount of Substance (CCQM) and for Units (CCU). The workshop aimed to
[...] Read more.
This article provides a report of the recent workshop on “The metrology of quantities which can be counted” organised jointly by the International Committee for Weights and Measures’ Consultative Committees for Amount of Substance (CCQM) and for Units (CCU). The workshop aimed to trigger a discussion on counting and number quantities across the metrological community so that a common understanding of counting and a common nomenclature could be achieved and there was clarity on the differences between these increasingly important concepts. This article details the background to the workshop, provides a summary of the presentations given and the discussions on the topics raised. It also reports the conclusions, agreed actions and next steps resulting from the workshop.
Full article
Highly Accessed Articles
Latest Books
E-Mail Alert
News
Topics
Topic in
Applied Sciences, JMMP, Materials, Metrology, Sensors, Standards
Measurement Strategies and Standardization in Manufacturing
Topic Editors: Manuel Rodríguez-Martín, João Ribeiro, Roberto García MartínDeadline: 20 December 2024
Conferences
Special Issues
Special Issue in
Metrology
Novel Dynamic Measurement Methods and Systems
Guest Editors: Lukasz Scislo, Nina Szczepanik-Scislo, Serge DemidenkoDeadline: 30 June 2024
Special Issue in
Metrology
Advances in Magnetic Measurements
Guest Editor: Nicholas SammutDeadline: 5 August 2024
Special Issue in
Metrology
Developments in 3D Metrology Selected from the 3D Metrology Conference
Guest Editors: Stephen Kyle, Ben Hughes, Stuart Robson, Robert SchmittDeadline: 30 November 2024
Special Issue in
Metrology
Advances in Optical 3D Metrology Selected from the Third Optical 3D Metrology Workshop, 2024
Guest Editors: Giorgio Vassena, Fabio Remondino, Mark ShortisDeadline: 25 June 2025