{"title":"Wireless surface acoustic wave resonator sensors: fast Fourier transform, empirical mode decomposition or wavelets for the frequency estimation in one shot?","authors":"A. Scipioni, P. Rischette, Agnès Santori","doi":"10.5194/jsss-12-247-2023","DOIUrl":"https://doi.org/10.5194/jsss-12-247-2023","url":null,"abstract":"Abstract. Most applications which measure physical quantities, especially in harsh environments, rely on surface acoustic wave resonators (SAWRs). Measuring the variation of the resonance frequency is a fundamental step in such cases. This article presents a comparison between three techniques for best determining the resonance frequency in one shot from the point of accuracy and uncertainty: fast Fourier transform (FFT), discrete wavelet transform (DWT) and empirical mode decomposition (EMD). After proposing a model for the generation of synthetic SAW signals, the question of wavelet choice is answered. The three techniques are applied to synthetic signals with different central frequencies and signal-to-noise ratios (SNRs). They are also tested on experimental signals with different sampling rates, number of samples and SNRs. Results are discussed in terms of the accuracy of the estimated frequency and measurement uncertainty. This study is successfully extended to SAWR temperature sensors.","PeriodicalId":17167,"journal":{"name":"Journal of Sensors and Sensor Systems","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139269387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Monitoring ammonia slip from large-scale selective catalytic reduction (SCR) systems in combined heat and power generation applications with field effect gas sensors","authors":"Lida Khajavizadeh, Mike Andersson","doi":"10.5194/jsss-12-235-2023","DOIUrl":"https://doi.org/10.5194/jsss-12-235-2023","url":null,"abstract":"Abstract. Following tightened regulations, selective catalytic reduction (SCR) of nitrogen oxides (NOx) by ammonia (NH3) has over the last couple of decades found wider adoption as a means of reducing NOx emissions from e.g. power production and district heating plants. As in the SCR process NH3 injected into the flue gas reacts with and reduces NOx to nitrogen (N2) and water (H2O) on the surface of a specific catalyst, the NH3 injection has to be dynamically adjusted to match both instant and long-term variations in flue gas nitrogen oxide concentration in order to minimize NOx and NH3 emissions. One possibility of realizing such NH3 dosing control would be the real-time monitoring and feedback of downstream flue gas NOx and NH3 concentrations to the NH3 injection control unit. In this study the sensing characteristics and performance of SiC-based Metal Oxide Semiconductor Field Effect Transistor (MOSFET) sensors with a structurally tailored gas-sensitive gate contact of iridium (Ir) for in situ NH3 monitoring downstream from the SCR catalyst in a combined heat and power (CHP) plant have therefore been investigated and evaluated. The sensor's NH3 sensitivity and selectivity as well as the cross-sensitivity to common flue gas components – oxygen (O2), water vapour (H2O), nitric oxide (NO), nitrogen dioxide (NO2), carbon monoxide (CO), and a model hydrocarbon, ethene (C2H4) – were thereby investigated for relevant concentration ranges under controlled conditions in the laboratory. While, at the prescribed sensor operation temperature of 300 ∘C, the influence of H2O, CO, and C2H4 on the sensor's NH3 concentration reading could be regarded as practically insignificant, a moderate cross-sensitivity was observed between NH3 and NO2 and, to a lesser extent, between NH3 / NO and NH3 / O2. As the NOx concentration downstream from the SCR catalyst under normal SCR and power plant operation is expected to be considerably smaller than the NH3 concentration whenever any appreciable ammonia slip occurs, the observed NH3 / NOx cross-sensitivities may, however, be of less practical significance for ammonia monitoring in real flue gases downstream from the SCR catalyst. Furthermore, if required, the small influence of O2 concentration variations on the sensor reading may also be compensated for by utilizing the signal from a commercially available oxygen sensor. Judging from in situ measurements performed in a combined heat and power plant, the structurally tailored Ir gate field effect sensors also exhibit good NH3 sensitivity over the relevant 0–40 ppm range when directly exposed to real flue gases, offering an accuracy of ±3 ppm as well as low sensor signal drift, the latter most likely to further improve with regular zero-point calibration and thereby make the Ir gate MOSFET ammonia sensor a promising alternative for cost-efficient real-time ammonia slip monitoring or SCR system control in heat and/or power production plants.","PeriodicalId":17167,"journal":{"name":"Journal of Sensors and Sensor Systems","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135436198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Analysis of thermal-offset drift of a high-resolution current probe using a planar Hall resistance sensor","authors":"N. K. Lee, Jaesoo Kim, Daesung Lee","doi":"10.5194/jsss-12-225-2023","DOIUrl":"https://doi.org/10.5194/jsss-12-225-2023","url":null,"abstract":"Abstract. We developed a pin-type current probe with high sensitivity, targeting electrical-probing printed circuit boards (PCBs). The developed sensor showed good enough characteristics, with 1 mA resolution on current measurements and up to 1 MHz operating frequency for analyzing highly integrated PCBs. During its characterization, however, we experienced a monotonously varying output signal in the time range of a few tens of minutes. We modeled it as the thermal-offset drift, being caused by Joule heating during sensor operation, and\u0000showed several solutions for reducing the offset by modifying the planar Hall resistance (PHR)\u0000layout and electric operation conditions and applying sensor circuitry with\u0000pulse width modulation.\u0000","PeriodicalId":17167,"journal":{"name":"Journal of Sensors and Sensor Systems","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46224315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maximilian Koehne, Christopher Schmidt, Satnam Singh, Andreas Grasskamp, T. Sauerwald, Gina Zeh
{"title":"Development of a gas chromatography system coupled to a metal-oxide semiconductor (MOS) sensor, with compensation of the temperature effects on the column for the measurement of ethene","authors":"Maximilian Koehne, Christopher Schmidt, Satnam Singh, Andreas Grasskamp, T. Sauerwald, Gina Zeh","doi":"10.5194/jsss-12-215-2023","DOIUrl":"https://doi.org/10.5194/jsss-12-215-2023","url":null,"abstract":"Abstract. A possible way to reduce the size and complexity of\u0000common gas chromatography (GC) systems is the economization of the column\u0000temperature regulation system. To this end, a temperature compensation\u0000method was developed and validated on a benchtop GC-PDD (pulsed discharge\u0000detector) with ethene. An in-house-developed algorithm correlates the\u0000retention index of a test gas to the retention index of a previously\u0000selected reference gas. To investigate further methods of cost reduction,\u0000commercial gas sensors were tested as cheap, sensitive, and versatile\u0000detectors. Therefore, CO2 was chosen as a naturally occurring reference gas, while ethene was chosen as a maturity marker for climacteric fruits and\u0000hence as a test gas. A demonstrator, consisting of a simple\u0000syringe injection system, a PLOT (porous layer open tubular) column boxed in\u0000a polystyrene-foam housing, a commercial MOS (metal-oxide semiconductor)\u0000sensor for the test gas, and a CO2-specific IR (infrared) sensor, was\u0000used to set up a simple GC system and to apply this method on\u0000test measurements. Sorption parameters for ethene and CO2 were\u0000determined via a van 't Hoff plot, where the entropy S was −11.982 J mol−1 K−1 ΔSEthene0 and 1.351 J mol−1 K−1 ΔSCarbondioxide0, and the enthalpy H was −20.622 kJ mol−1 ΔHEthene0 and −14.792 kJ mol−1 ΔHCarbondioxide0, respectively. Ethene (100 ppm) measurements\u0000revealed a system-specific correction term of 0.652 min. Further\u0000measurements of ethene and interfering gases revealed a mean retention time\u0000for ethene of 3.093 min; the mean predicted retention time is 3.099 min. The\u0000demonstrator was able to identify the test gas, ethene, as a function of\u0000the reference gas, CO2, in a first approach, without a column heating\u0000system and in a gas mixture by applying a temperature compensation algorithm\u0000and a system-specific holdup time correction term.\u0000","PeriodicalId":17167,"journal":{"name":"Journal of Sensors and Sensor Systems","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45138986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Methods to investigate the temperature distribution of heated ceramic gas sensors for high-temperature applications","authors":"T. Wöhrl, J. Herrmann, J. Kita, R. Moos, G. Hagen","doi":"10.5194/jsss-12-205-2023","DOIUrl":"https://doi.org/10.5194/jsss-12-205-2023","url":null,"abstract":"Abstract. The temperature-dependent properties of sensor films for measuring the concentration of various gas components affect, to a large extent, the sensor characteristics of planar gas sensors. Therefore, it is important to know the temperature distribution of the gas-sensitive films of such\u0000sensors precisely. Using screen-printed thermocouples and a thermal-imaging\u0000camera, two principles for determining the temperature profile of gas\u0000sensors inside of a protection cap are shown and compared in this study. The\u0000data agree well, and the results can be used in future to determine the\u0000influences of varying flow and temperature conditions on the temperature\u0000profile of a sensor and to reduce such effects by adapting the periphery, e.g.,\u0000by designing appropriate protection caps.\u0000","PeriodicalId":17167,"journal":{"name":"Journal of Sensors and Sensor Systems","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45569590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"New publication of the VDI/VDE guideline 3520 “Surface temperature measurement with contact thermometers” – contents and background of the development","authors":"S. Augustin, M. Schalles","doi":"10.5194/jsss-12-197-2023","DOIUrl":"https://doi.org/10.5194/jsss-12-197-2023","url":null,"abstract":"Abstract. Temperature measurement at the surface of solids by means of contact thermometers has its own metrological characteristics, which are\u0000in contrast to characteristics of the measurement with immersed contact\u0000thermometers. They significantly influence the accuracy and the measurement\u0000uncertainty of the measured temperature and its deviations. Up to now, no\u0000national or international guideline exists which deals with the\u0000determination of the static and dynamic measurement deviations. Therefore,\u0000the guideline committee “VDI/VDE-GMA FA 4.62 Contact Thermometry” has\u0000developed the new VDI (Association of German Engineers) and VDE (Association for Electrical, Electronic and Information Technologies) guideline 3520 “Surface temperature measurement\u0000with contact thermometers”. It contains information about the most important properties of contact surface thermometers and error sources, and it presents typical measurement results for various applications. In addition, the parameters influencing the measurement result and test equipment for their determination are described, and concrete examples of thermometer data sheets are given.\u0000","PeriodicalId":17167,"journal":{"name":"Journal of Sensors and Sensor Systems","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46445453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Metrological assessment of a robotic total station for use in post-earthquake emergency conditions","authors":"G. D'Emilia, E. Natale","doi":"10.5194/jsss-12-187-2023","DOIUrl":"https://doi.org/10.5194/jsss-12-187-2023","url":null,"abstract":"Abstract. The paper provides synthetic indications regarding the measuring performances of procedures for using a robotic total station (RTS) in emergency situations, such as the survey of the structural conditions of buildings and the assessment of the safety level for rescue operations after the occurrence of an earthquake. Particular attention is paid to operative aspects that could impact on the performance of the system in this situation; specifically considered is the effect of the layout of the measurement setup and of the number of monitoring points, depending on the geometry of the site and of the considered buildings, because the criticality of emergency conditions imposes geometrical solutions which are far from having optimal solutions. The analysis is carried out with reference to two different buildings, which have different characteristics from the point of view of height and distance from the instrument, and that implies different geometrical constraints for the instrument during the acquisition of the monitoring\u0000points. The methodology allows the evaluation of the repeatability, reproducibility, and detection limit of a RTS, in field conditions, referring to a 1-year observation period, with reference to different quantities, like positions of the monitoring points and the inclination of walls and façades. In particular, the analysis of the geometrical characteristics of reduced configurations of the monitoring points has highlighted interesting aspects in view of defining a simplified procedure, which is also suitable for speeding up the acquisition of reliable data in emergency conditions.\u0000","PeriodicalId":17167,"journal":{"name":"Journal of Sensors and Sensor Systems","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47120385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Bergmann, Norbert Halmen, C. Scalfi-happ, Dominik Reitzle, A. Kienle, Linda Mittelberg, B. Baudrit, T. Hochrein, M. Bastian
{"title":"Investigation of the degree of cross-linking of polyethylene and thermosets using absolute optical spectroscopy and Raman microscopy","authors":"F. Bergmann, Norbert Halmen, C. Scalfi-happ, Dominik Reitzle, A. Kienle, Linda Mittelberg, B. Baudrit, T. Hochrein, M. Bastian","doi":"10.5194/jsss-12-175-2023","DOIUrl":"https://doi.org/10.5194/jsss-12-175-2023","url":null,"abstract":"Abstract. In the research work presented here, an integrating sphere demonstrator which is suitable for the non-destructive determination of the degree of cross-linking or curing and has the potential for use as an at-line device for in-process quality assurance was assembled and explored. The measurement system allows the analysis of absorption and scattering coefficients of materials independently by means of absolute optical spectroscopy. The two optical parameters showed a good correlation with the degree of cross-linking of cross-linked polyethylene (PE-X) and the degree of curing of different thermosets and adhesives, each of which was determined using different reference methods (wet chemical analysis, differential scanning calorimetry (DSC), and dielectric analysis (DEA)). The results show that different PE-X materials can be distinguished well by their absorption and scattering in the visual (VIS) and near-infrared (NIR) wavelength range, respectively, and conclusions on their degree of cross-linking are possible. Also, the curing of resins can be monitored based on the absorption. In addition, Raman spectroscopy was used to achieve a better understanding of the material changes during the cross-linking of the materials. It also showed a good suitability for monitoring the curing processes in thermosets. In summary, the new method can be used to determine the crucial parameters of these industrial important material types and fulfils the great demand for fast, non-destructive testing, which can be carried out during the process or on the finished product.\u0000","PeriodicalId":17167,"journal":{"name":"Journal of Sensors and Sensor Systems","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47835494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Leander Claes, Nadine Feldmann, Veronika Schulze, Lars Meihost, Henrik Kuhlmann, Benjamin Jurgelucks, Andrea Walther, Bernd Henning
{"title":"Inverse procedure for measuring piezoelectric material parameters using a single multi-electrode sample","authors":"Leander Claes, Nadine Feldmann, Veronika Schulze, Lars Meihost, Henrik Kuhlmann, Benjamin Jurgelucks, Andrea Walther, Bernd Henning","doi":"10.5194/jsss-12-163-2023","DOIUrl":"https://doi.org/10.5194/jsss-12-163-2023","url":null,"abstract":"Abstract. An inverse measurement procedure for the determination of a full set of piezoelectric material parameters using a single sample is presented. The basis for the measurement procedure is a measurement of the frequency-dependent impedance of the sample. To yield sufficient sensitivity of this measurement with respect to all material parameters (mechanical, electrical, and coupling parameters), an optimal electrode configuration for the sample is determined before the inverse measurement procedure is realised using a novel topology optimisation approach. After initial estimates for the material parameters are provided by analytical expressions, a sensitivity-based, staged, local optimisation procedure yields material parameters for the sample by fitting the impedance of a finite element simulation model to the measured electrical impedance. Results for different absorption models as well as for different piezoelectric materials (hard, soft, and lead-free piezoceramics) are included.","PeriodicalId":17167,"journal":{"name":"Journal of Sensors and Sensor Systems","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135691682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Approximate sequential Bayesian filtering to estimate 222Rn emanation from 226Ra sources using spectral time series","authors":"F. Mertes, S. Röttger, A. Röttger","doi":"10.5194/jsss-12-147-2023","DOIUrl":"https://doi.org/10.5194/jsss-12-147-2023","url":null,"abstract":"Abstract. A new approach to assess the emanation of 222Rn from\u0000226Ra sources based on γ-ray spectrometric measurements is\u0000presented. While previous methods have resorted to steady-state treatment of\u0000the system, the method presented incorporates well-known radioactive decay\u0000kinetics into the inference procedure through the formulation of a\u0000theoretically motivated system model. The validity of the 222Rn\u0000emanation estimate is thereby extended to regimes of changing source\u0000behavior, potentially enabling the development of source surveillance\u0000systems in the future. The inference algorithms are based on approximate\u0000recursive Bayesian estimation in a switching linear dynamical system,\u0000allowing regimes of changing emanation to be identified from the spectral\u0000time series while providing reasonable filtering and smoothing performance\u0000in steady-state regimes. The derived method is applied to an empirical\u0000γ-ray spectrometric time series obtained over 85 d and is able to\u0000provide a time series of emanation estimates consistent with the physics of\u0000the emanation process.\u0000","PeriodicalId":17167,"journal":{"name":"Journal of Sensors and Sensor Systems","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49423946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}