J. Goldschmidt, Elisabeth Moser, L. Nitzsche, Rudolf Bierl, J. Wöllenstein
{"title":"Improving the performance of artificial neural networks trained on synthetic data in gas spectroscopy – a study on two sensing approaches","authors":"J. Goldschmidt, Elisabeth Moser, L. Nitzsche, Rudolf Bierl, J. Wöllenstein","doi":"10.1515/teme-2023-0051","DOIUrl":"https://doi.org/10.1515/teme-2023-0051","url":null,"abstract":"Abstract Artificial neural networks (ANNs) are used in quantitative infrared gas spectroscopy to predict concentrations on multi-component absorption spectra. Training of ANNs requires vast amounts of labelled training data which may be elaborate and time consuming to obtain. Additional data can be gained by the utilization of synthetically generated spectra, but at the cost of systematic deviations to measured data. Here, we present two approaches to train ANNs with a combination of comparatively small, measured data sets and synthetically generated data. For the first approach a neural network is trained hybridly with synthetically generated infrared absorption spectra of mixtures of N2O and CO and measured zero-gas spectra, taken with a mid-infrared dual comb spectrometer. This improves the mean absolute error (MAE) of the network predictions from 0.46 to 0.01 ppmV and 0.24 to 0.01 ppmV for the concentration predictions of N2O and CO respectively for zero-gas measurements which was previously observed for training with purely synthetic data. At the same time a similar performance on spectra from gas mixtures of 0–100 ppmV N2O and 0 to 60 ppmV CO was achieved. For the second approach an ANN pre-trained on synthetic infrared spectra of mixtures of acetone and ethanol is retrained on a small dataset consisting of 26 spectra taken with a mid-infrared photoacoustic spectrometer. In this case the MAE for the concentration predictions of ethanol and acetone are improved by 45 % and 20 % in comparison to purely synthetic training. This shows the capability of using synthetically generated data to train ANNs in combination with small amounts of measured data to further improve neural networks for gas sensing and the transferability between different sensing approaches.","PeriodicalId":56086,"journal":{"name":"Tm-Technisches Messen","volume":"78 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90534000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Investigations on terthiophene as an electrically conductive polymer for UV laser lithography","authors":"T. Ziemer, G. Ziegmann, C. Rembe","doi":"10.1515/teme-2023-0023","DOIUrl":"https://doi.org/10.1515/teme-2023-0023","url":null,"abstract":"Abstract Polymers hold great potential for the use in microsensors and organic electronics. They are highly adaptable, easy to process and can contribute new or improved capabilities compared to semiconductors. Direct UV laser lithography also gains increasing attention. Because it avoids expensive photomasks, it is especially attractive where small numbers of specialized microcomponents are needed, like in prototyping. Lithography necessitates materials, which can be shaped by UV radiation. For many microsensor applications, there is the additional requirement of electric conductivity, preferably in the same material. We approached this demand by combining a novolak and terthiophene doped with copper(II) perchlorate to form an interpenetrating polymer network, which possesses properties of both of its constituents. From this, we manufactured test structures with the UV laser of a micro pattern generator. In previous conference contributions, we showed a first proof of principle. In this publication, we present results of new experiments that demonstrate the characteristics in more detail. We improved our electrical setup to conduct four-terminal measuring. We used it to first verify previous results and investigated the material’s response to alternating currents up to 10 kHz. We then compared the electrical resistivity of differently sized structures for temperatures between 20 and 90 °C and examined long-term stability of their resistance by subjecting samples to temperatures of up to 60 °C for several hours. Additionally, we tested the influence of UV radiation on the resistance. Our samples exhibited good lithographic qualities. Resistivities were around 2 Ω mm and temperature sensitivity up to −407 Ω K−1. UV radiation induced a partially reversible increase of the electric resistance. The long-term stability of the material was temperature-dependent.","PeriodicalId":56086,"journal":{"name":"Tm-Technisches Messen","volume":"41 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77701968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Holger Kahmann, Kai Geva, C. Schlegel, Rolf Kumme, F. Härtig
{"title":"Design der 5 MN·m Drehmoment-Normalmesseinrichtung","authors":"Holger Kahmann, Kai Geva, C. Schlegel, Rolf Kumme, F. Härtig","doi":"10.1515/teme-2023-0057","DOIUrl":"https://doi.org/10.1515/teme-2023-0057","url":null,"abstract":"Zusammenfassung Dieser Artikel beschreibt den finalen Aufbau und das Funktionsprinzip der neuen 5 MN·m Drehmoment-Normalmesseinrichtung (Dm-NME) der Physikalisch-Technischen Bundesanstalt (PTB). Die Maschine ist für mechanische Mehrkomponentenbelastung ausgelegt und kann neben dem Drehmoment, eine Axialkraft, Biegemomente und Querkräfte auf den Prüfling übertragen. Das Design der Maschine ist so optimiert, daß die Einflüsse parasitärer Komponenten auf das Hauptdrehmoment weitgehend reduziert werden.","PeriodicalId":56086,"journal":{"name":"Tm-Technisches Messen","volume":"40 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79878537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Sehlmeyer, M. Bhavsar, Julian Biebighaeuser, M. Hitzemann, H. Maier, M. Lippmann, C. Schaefer, S. Zimmermann
{"title":"Impedance spectroscopy of enlarged cochlear implant stimulation electrodes – FEM simulations considering the perilymph","authors":"M. Sehlmeyer, M. Bhavsar, Julian Biebighaeuser, M. Hitzemann, H. Maier, M. Lippmann, C. Schaefer, S. Zimmermann","doi":"10.1515/teme-2023-0091","DOIUrl":"https://doi.org/10.1515/teme-2023-0091","url":null,"abstract":"Abstract Cochlear implants are hearing prostheses for patients with severe to total hearing loss but intact auditory nerve. An external speech processor captures sound from the environment, which is subsequently converted into electrical signals and transmitted to an electrode array in the patient’s inner ear. The metallic stimulation electrodes of the electrode array electrically stimulate the spiral ganglion cells of the auditory nerve. The functionality of cochlear implants strongly depends on the possible maximum current stimulating the spiral ganglion cells, which can be affected by, e.g., cell growth around the stimulation electrodes. This in turn decreases the stimulation efficiency leading to decreased hearing. Cell growth, implant position and other changes in the surrounding medium are reflected in a change of the impedance of the stimulation electrodes. The impedance measurement of the stimulation electrodes is already implemented in all common cochlear implant systems to check functionality of the stimulation electrodes after implantation, but the frequency spectrum is normally not analyzed. Although this method can detect cell growth on the stimulation electrodes, it faces limitations when other interfering effects, such as changes in the perilymph and implant position, influence the impedance. This work shows impedance spectroscopic measurements using enlarged cochlear implant models to electrically analyze the surrounding medium, the perilymph, to understand changes in electrode impedance and to later monitor the stimulation efficiency of cochlear implants and to identify possible reasons for decreased hearing ability by impedance spectroscopy. In addition, we use FEM simulations to numerically model the influence of the perilymph composition on the impedance measurement. As shown by a final validation, this model can serve as a basis for an extended simulation model including implant position and cell growth monitoring to predict hearing deterioration in cochlear implant patients. In this context, this work serves as a basis for the development of a holistic prediction model and considers in the first step exclusively the influence of the perilymph composition on the impedance between two stimulation electrodes.","PeriodicalId":56086,"journal":{"name":"Tm-Technisches Messen","volume":"6 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80026747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xumei Lin, Guanghui Zhu, Shijie Yu, Peng Wang, Penggang Wang
{"title":"A reinforced corrosion assessment method based on the new magnetic sensor and improved adaptive filtering","authors":"Xumei Lin, Guanghui Zhu, Shijie Yu, Peng Wang, Penggang Wang","doi":"10.1515/teme-2023-0050","DOIUrl":"https://doi.org/10.1515/teme-2023-0050","url":null,"abstract":"Abstract Corrosion assessment of reinforced concrete structures is the basis for subsequent corrosion repair and early warning of structural hazards. Aiming at the problem of accurately measuring the corrosion degree of reinforced concrete structures in coastal area, a New Magnetic Sensor (NMS) based on the theory of magnetic medium is designed in this paper. A functional model of the relationship between magnetic induction intensity change and reinforcement mass loss based on multi-point detection is constructed, and an improved adaptive filtering Least Mean Square (LMS) algorithm is proposed to realize damage identification and quantitative calculation of reinforcement corrosion comprehensively. Through numerical simulation experiments, the feasibility of designing the sensor is verified. The measured corrosion test of the sensor prototype shows that the calculated corrosion rates of different steel corrosion degrees are in good agreement with the actual values, with an average relative error of 1.64 %. The sensor provides a new method for corrosion monitoring of reinforced concrete structures.","PeriodicalId":56086,"journal":{"name":"Tm-Technisches Messen","volume":"2 1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76337941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Das Virtuelle Koordinatenmessgerät – ein Digitaler Metrologischer Zwilling","authors":"F. Härtig, K. Kniel, Daniel Heißelmann","doi":"10.1515/teme-2023-0066","DOIUrl":"https://doi.org/10.1515/teme-2023-0066","url":null,"abstract":"Zusammenfassung Koordinatenmessgeräte (KMG) sind universell einsetzbare Längenmessgeräte zur Erfassung dreidimensionaler Objekte. Bei einer Messung unterliegen die einzelnen Messpunkte individuellen Einflüssen, die zur Messunsicherheit der Messergebnisse beitragen. Sind alle signifikanten Einflüsse erfasst, kann ein Messprozess mit dem sogenannten Virtuellen Koordinatenmessgerät (VCMM) vollständig simuliert werden. Ein wesentliches Ziel des VCMM ist die automatische Berechnung eines Messergebnisses unter Angabe eines Messwertes und seiner zugehörigen Messunsicherheit. Dies ist insbesondere für die noch in der Entwicklung befindlichen Rückführung für dimensionelle Messaufgaben an Großbauteilen für die Windenergie von Bedeutung, da materielle Normale in der erforderlichen Größe oftmals nicht zur Verfügung stehen. Für derart neue metrologische Herausforderungen werden Digitale Metrologische Zwillinge (D-MT), die wie das VCMM einen Messprozess vollständig abbilden, von zentraler Bedeutung. Dieser Beitrag beschreibt erstmalig die Definition für einen D-MT und die daraus resultierenden grundlegenden Anforderungen. An Messaufgaben wird gezeigt, welche Kriterien für vertrauenswürdige Eingangsdaten eines D-MT erfüllt sein müssen. Darüber hinaus wird auf die wichtige Unterscheidung zwischen systematisch bekannten, systematisch unbekannten und zufälligen Abweichungen eingegangen. Abschließend wird beschrieben, wie die zuverlässige Nutzung eines D-MT validiert und quantifiziert werden kann.","PeriodicalId":56086,"journal":{"name":"Tm-Technisches Messen","volume":"75 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75096959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Stefan Oertel, M. Eggert, P. Wilhelm, Julia Hornig
{"title":"Windkanalmesseinrichtung für das bistatische PTB-Wind-Lidar","authors":"Stefan Oertel, M. Eggert, P. Wilhelm, Julia Hornig","doi":"10.1515/teme-2023-0052","DOIUrl":"https://doi.org/10.1515/teme-2023-0052","url":null,"abstract":"Zusammenfassung Im Zusammenhang mit dem Erreichen der Klimaziele durch den Einsatz erneuerbarer Energien wurde in der Physikalisch-Technischen Bundesanstalt (PTB) in den letzten Jahren ein bistatisches Wind-Lidar (Light detection and ranging) entwickelt und aufgebaut. Dieses Wind-Lidar ermöglicht die für Windenergieanlagen notwendige Rückführung von Windgeschwindigkeiten in Höhen von 5 m bis 250 m mit kleinsten Messunsicherheiten in beliebigem Gelände, und stellt damit erstmals eine unabhängige Alternative zu bisher eingesetzten, kostspieligen Windmessmasten dar. Der geplante Einsatz des PTB-Lidars als rückgeführtes Transfernormal im Bereich der Windfernmessung erfordert neben vorherigen Vergleichsmessungen mit anderen Windfernmesssystemen in freiem Gelände auch eine detaillierte Untersuchung des PTB-Lidars unter kontrollierbaren Strömungsbedingungen zur Validierung seiner Messunsicherheit und Überwachung seiner Langzeitstabilität. Aus diesem Grund wurde im Kompetenzzentrum für Windenergie (CCW) der PTB ein neuer, speziell konstruierter Windkanal mit einem Laser-Doppler-Anemometer (LDA) als Strömungsgeschwindigkeitsnormal auf einer Plattform in 8 m Höhe errichtet. Dies ermöglicht es, das PTB-Lidar unterhalb der Messstrecke des Windkanals zu positionieren und auf die SI-Einheiten-rückgeführte Strömungsgeschwindigkeitsmessungen mit dem Wind-Lidar durchzuführen. Der Windkanal nach Göttinger Bauart hat eine offene Messstrecke mit einer Länge von 75 cm und einer Querschnittsfläche von 50 × 50 cm2. In der Messstrecke wird eine hohe Strömungshomogenität und ein niedriger Turbulenzgrad von <0,35 % im Geschwindigkeitsbereich von 1 m/s bis 30 m/s erreicht. Die erweiterte Messunsicherheit des LDA-Referenznormals beträgt 0,16 %. Sämtliche im Windkanal durchgeführten Vergleichsmessungen zeigen eine Geschwindigkeitsabweichung zwischen dem Lidar-System und dem LDA-Referenznormal von unter ±0,5 %. Eine Optimierung der Methode zur Positionierung und damit Lokalisierung des Lidar-Messvolumens in der Windkanalmessstrecke über einen dünnen Partikelfilm führte zu einer reproduzierten Verringerung der Geschwindigkeitsabweichung auf circa −0,10 %.","PeriodicalId":56086,"journal":{"name":"Tm-Technisches Messen","volume":"411 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79916797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Metrologisches Kompetenzzentrum für Windenergie","authors":"Andreas Fischer, F. Härtig","doi":"10.1515/teme-2023-0096","DOIUrl":"https://doi.org/10.1515/teme-2023-0096","url":null,"abstract":"","PeriodicalId":56086,"journal":{"name":"Tm-Technisches Messen","volume":"170 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74988461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Parasitic load components for torque and force calibration: a Digital Twin concept","authors":"Kai Mienert, O. Baer, C. Giusca, A. Prato","doi":"10.1515/teme-2023-0061","DOIUrl":"https://doi.org/10.1515/teme-2023-0061","url":null,"abstract":"Abstract The 5 MN·m standard torque machine within the Competence Centre for Wind Energy (CCW) was developed at PTB. The Digital Twin (DT) of the torque transducer mounted inside the machine was developed to enable errors eliminations and resources optimization during operation. The machine can apply not only torque, but also bending moments and shear forces. At the same time, the DT concepts of force measurement devices and their application for static, continuous and dynamic calibrations was developed to improve calibration processes, preserve data quality and collect calibration data for improved decision making. In order to illustrate the functionality of both developed DT concepts, a study of parasitic load components in both devices is carried out using simulation with ANSYS and ABAQUS engineering software. The validation of the DT models was carried out using traceable measurements. The way to combine both concepts for comprehensive shading of the standard torque machine is discussed.","PeriodicalId":56086,"journal":{"name":"Tm-Technisches Messen","volume":"26 1","pages":"565 - 575"},"PeriodicalIF":1.0,"publicationDate":"2023-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80001254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Eichung im Wandel – Veränderungen bei gesetzlich geregelten Messgeräten","authors":"P. Ulbig","doi":"10.1515/teme-2023-0003","DOIUrl":"https://doi.org/10.1515/teme-2023-0003","url":null,"abstract":"Zusammenfassung Digitalisierung und Energiewende verändern unser Leben in großen Schritten. Den Eichbehörden kommt dabei nach wie vor mit ihrer messtechnischen Kompetenz die Aufgabe zu für Verbraucherschutz und fairen Wettbewerb zu sorgen. Es werden Beispiel gezeigt, wie sich einerseits eichtechnische Aufgaben verringern (z. B. Abgasmessgeräte und Taxameter), aber andererseits viele neue Aufgaben hinzukommen (z. B. Ladesäulen, neue nachhaltige Treibstoffe, intelligente Messsysteme).","PeriodicalId":56086,"journal":{"name":"Tm-Technisches Messen","volume":"7 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78395883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}