Metrology

8 pages, 3091 KiB

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://doi.org/10.3390/metrology3040024 - 12 Dec 2023

Viewed by 1150

Abstract

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

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4 pages, 190 KiB

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://doi.org/10.3390/metrology3040023 - 23 Nov 2023

Viewed by 1069

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)

12 pages, 4917 KiB

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://doi.org/10.3390/metrology3040022 - 22 Nov 2023

Viewed by 2180

Abstract

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

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18 pages, 13447 KiB

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://doi.org/10.3390/metrology3040021 - 30 Oct 2023

Cited by 1 | Viewed by 1354

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 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)

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22 pages, 7214 KiB

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://doi.org/10.3390/metrology3040020 - 6 Oct 2023

Viewed by 1241

Abstract

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

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Metrology, Volume 3, Issue 4 (December 2023) – 5 articles

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