@misc{55416,
  author       = {{Claes, Leander and Koch, Kevin and Friesen, Olga and Meihost, Lars}},
  title        = {{{Machine learning in inverse measurement problems: An application to piezoelectric material characterisation}}},
  year         = {{2024}},
}

@article{56777,
  abstract     = {{The estimation of accurate piezoelectric material parameters is a fundamental prerequisite for simulation-driven design of piezoelectric actuators and sensors. Previous studies show that a full set of material parameters can be determined in an inverse procedure using a single disc-shaped specimen with an electrode structured for increased sensitivity with respect to all material parameters. However, in the case of high-power actuator applications, ring-shaped piezoelectric components are often employed, necessitating an adaptation of the previously developed method. The alteration in geometry introduces some advantages. Accordingly, there is no longer any requirement to modify the electrode structure in order to enhance sensitivity. The method to estimate the material parameters presented here consists of a total of three stages. An initial, approximate estimation of the material parameters is determined using analytical approximations for the resonance frequencies from the IEEE standard. These values are optimised in an inverse procedure that employs analytic expressions for the electrical impedance of piezoelectric rings as the forward model. Further refinement is achieved by using Finite Element (FE) simulations as the forward model again in an inverse procedure. The method is applied to electrical impedance measurement data, yielding material parameters for hard piezoelectric rings. The result shows a good agreement between the simulation and measurement results, indicating realistic material parameter values.}},
  author       = {{Friesen, Olga and Claes, Leander and Feldmann, Nadine and Henning, Bernd}},
  issn         = {{2196-7113}},
  journal      = {{tm - Technisches Messen}},
  publisher    = {{De Gruyter}},
  title        = {{{Estimation of piezoelectric material parameters of ring-shaped specimens}}},
  doi          = {{https://doi.org/10.1515/teme-2024-0107}},
  year         = {{2024}},
}

@article{54314,
  author       = {{Koch, Kevin and Claes, Leander and Jurgelucks, Benjamin and Meihost, Lars}},
  journal      = {{tm - Technisches Messen}},
  publisher    = {{Walter de Gruyter GmbH}},
  title        = {{{Neuronale Netze zur Startwertschätzung bei der Identifikation piezoelektrischer Materialparameter}}},
  doi          = {{10.1515/teme-2024-0099}},
  year         = {{2024}},
}

@inproceedings{47138,
  author       = {{Hetkämper, Tim and Koch, Kevin and Webersen, Manuel and Claes, Leander}},
  booktitle    = {{SEFI 51th Annual Conference Proceedings - Engineering Education for Sustainability}},
  publisher    = {{SEFI}},
  title        = {{{Application-based learning of signal analysis methods with the help of a graphical open-source software}}},
  doi          = {{10.21427/159K-G445}},
  year         = {{2023}},
}

@article{48053,
  author       = {{Hetkämper, Tim and Claes, Leander and Henning, Bernd}},
  issn         = {{2196-7113}},
  journal      = {{tm - Technisches Messen}},
  keywords     = {{Electrical and Electronic Engineering, Instrumentation}},
  number       = {{s1}},
  pages        = {{49--54}},
  publisher    = {{Walter de Gruyter GmbH}},
  title        = {{{Vorzeichenrichtige tomographische Rekonstruktion von Ultraschallfeldern mit Hilfe der Schlierentechnik}}},
  doi          = {{10.1515/teme-2023-0069}},
  volume       = {{90}},
  year         = {{2023}},
}

@inproceedings{43233,
  author       = {{Zeipert, Henning and von Germeten, Christian and Friesen, Olga and Claes, Leander and Johannesmann, Sarah and Henning, Bernd}},
  booktitle    = {{Fortschritte der Akustik - DAGA 2023}},
  location     = {{Hamburg}},
  pages        = {{819--822}},
  title        = {{{Investigation of change in dispersive behaviour during adhesive curing in multi-layered structures}}},
  year         = {{2023}},
}

@inproceedings{43229,
  author       = {{Claes, Leander}},
  booktitle    = {{Fortschritte der Akustik - DAGA 2023}},
  location     = {{Hamburg}},
  pages        = {{7--14}},
  title        = {{{Bestimmung der Volumenviskosität mittels akustischer Absorptionsmessung}}},
  year         = {{2023}},
}

@inproceedings{43234,
  author       = {{Nicolai, Marcel and Zeipert, Henning and Lugovtsova, Yevgeniya and Bulling, Jannis and Johannesmann, Sarah and Prager, Jens and Henning, Bernd}},
  booktitle    = {{Fortschritte der Akustik - DAGA 2023}},
  location     = {{Hamburg}},
  pages        = {{823--826}},
  title        = {{{Characterization of adhesion strength using guided ultrasonic waves}}},
  year         = {{2023}},
}

@article{37543,
  author       = {{Hetkämper, Tim and Koch, Kevin and Claes, Leander and Henning, Bernd}},
  journal      = {{tm - Technisches Messen}},
  keywords     = {{Schlierentechnik}},
  number       = {{2}},
  pages        = {{103--112}},
  publisher    = {{Walter de Gruyter GmbH}},
  title        = {{{Phase-preserving methods to visualise ultrasonic fields with schlieren imaging}}},
  doi          = {{10.1515/teme-2022-0112}},
  volume       = {{90}},
  year         = {{2023}},
}

@inproceedings{45205,
  author       = {{Dreiling, Dmitrij and Itner, Dominik and Hetkämper, Tim and Birk, Carolin and Gravenkamp, Hauke and Henning, Bernd}},
  booktitle    = {{SMSI 2023 Conference}},
  isbn         = {{978-3-9819376-8-8}},
  location     = {{Nürnberg}},
  pages        = {{394 -- 395}},
  publisher    = {{AMA Association For Sensors And Measurement}},
  title        = {{{Improved determination of viscoelastic material parameters using a pulse-echo measurement setup}}},
  doi          = {{10.5162/SMSI2023/P59}},
  year         = {{2023}},
}

@inproceedings{51117,
  author       = {{Scheidemann, Claus and Hemsel, Tobias and Friesen, Olga and Claes, Leander and Sextro, Walter}},
  location     = {{Jeju, Korea}},
  title        = {{{Influence of Temperature and Pre-Stress on the Piezoelectric Material Behavior of Ring-Shaped Ceramics}}},
  year         = {{2023}},
}

@article{45445,
  author       = {{Claes, Leander and Feldmann, Nadine and Schulze, Veronika and Meihost, Lars and Kuhlmann, Henrik and Jurgelucks, Benjamin and Walther, Andrea and Henning, Bernd}},
  journal      = {{Journal of Sensors and Sensor Systems}},
  number       = {{1}},
  pages        = {{163–173}},
  title        = {{{Inverse procedure for measuring piezoelectric material parameters using a single multi-electrode sample}}},
  doi          = {{10.5194/jsss-12-163-2023}},
  volume       = {{12}},
  year         = {{2023}},
}

@misc{45455,
  author       = {{Claes, Leander and Meihost, Lars and Jurgelucks, Benjamin}},
  title        = {{{Inverse procedure for the identification of piezoelectric material parameters supported by dense neural networks}}},
  year         = {{2023}},
}

@inproceedings{6590,
  author       = {{Nicolai, Marcel and Zeipert, Henning and Lugovtsova, Yevgeniya and Bulling, Jannis and Johannesmann, Sarah and Prager, Jens and Henning, Bernd}},
  booktitle    = {{Fortschritte der Akustik - DAGA 2022}},
  location     = {{Stuttgart}},
  pages        = {{1394--1397}},
  title        = {{{Quantification of the adhesive coupling of layered structures using guided ultrasonic waves}}},
  year         = {{2022}},
}

@misc{6561,
  author       = {{Hetkämper, Tim}},
  title        = {{{Visualisierung von Ultraschallfeldern mittels Schlierentechnik und fraktionaler Fouriertransformation}}},
  year         = {{2022}},
}

@misc{6592,
  author       = {{Claes, Leander}},
  title        = {{{Messverfahren für die akustische Absorption zur Bestimmung der Volumenviskosität}}},
  year         = {{2022}},
}

@article{6579,
  abstract     = {{An explicit approach using symplectic time integration in conjunction with traditional finite difference spatial derivatives to solve the wave equation in moving media is presented. A simple operator split of this second order wave equation into two coupled first order equations is performed, allowing these split equations to be solved symplectically. Orders of symplectic time integration ranging from first to fourth along with orders of spatial derivatives ranging from second to sixth are explored. The case of cylindrical acoustic spreading in air under a constant velocity in a 2D square structured domain is considered. The variation of the computed time-of-flight, frequency, and wave length are studied with varying grid resolution and the deviations from the analytical solutions are determined. It was found that symplectic time integration interferes with finite difference spatial derivatives higher than second order causing unexpected results. This is actually beneficial for unstructured finite volume tools like OpenFOAM where second order spatial operators are the state-of-the art. Cylindrical acoustic spreading is simulated on an unstructured 2D triangle mesh showing that symplectic time integration is not limited to the spatial discretization paradigm and overcomes the numerical diffusion arising with the in-built numerical methods which hinder wave propagation.}},
  author       = {{Inguva, Venkatesh and Feldmann, Nadine and Claes, Leander and Koturbash, Taras and Hahn-Jose, Thomas and Koutcherov, Vladimir and Kenig, Eugeny}},
  journal      = {{Engineering Reports}},
  title        = {{{An explicit symplectic approach to solving the wave equation in moving media}}},
  doi          = {{10.1002/eng2.12573}},
  year         = {{2022}},
}

@misc{17090,
  author       = {{Itner, Dominik and Gravenkamp, Hauke and Dreiling, Dmitrij and Birk, Carolin and Henning, Bernd}},
  publisher    = {{International Association for Computational Mechanics (IACM)}},
  title        = {{{Differentiation of an SBFE model in the context of material parameter determination}}},
  year         = {{2022}},
}

@article{30863,
  abstract     = {{<jats:title>Abstract</jats:title>
               <jats:p>In this paper a measurement procedure to identify viscoelastic material parameters of plate-like samples using broadband ultrasonic waves is presented. Ultrasonic Lamb waves are excited via the thermoelastic effect using laser radiation and detected by a piezoelectric transducer. The resulting measurement data is transformed to yield information about multiple propagating Lamb waves as well as their attenuation. These results are compared to simulation results in an inverse procedure to identify the parameters of an elastic and a viscoelastic material model.</jats:p>}},
  author       = {{Johannesmann, Sarah and Claes, Leander and Feldmann, Nadine and Zeipert, Henning and Henning, Bernd}},
  issn         = {{2196-7113}},
  journal      = {{tm - Technisches Messen}},
  keywords     = {{Electrical and Electronic Engineering, Instrumentation}},
  number       = {{7 - 8}},
  pages        = {{493 -- 506}},
  publisher    = {{Walter de Gruyter GmbH}},
  title        = {{{Lamb wave based approach to the determination of acoustic material parameters}}},
  doi          = {{10.1515/teme-2021-0134}},
  volume       = {{89}},
  year         = {{2022}},
}

@inproceedings{6588,
  author       = {{Johannesmann, Sarah and Claes, Leander and Henning, Bernd}},
  booktitle    = {{Fortschritte der Akustik - DAGA 2022}},
  location     = {{Stuttgart}},
  pages        = {{1401--1404}},
  title        = {{{Estimation of viscoelastic material parameters of polymers using Lamb waves}}},
  year         = {{2022}},
}