@article{SchopenNarayanBeckmannetal.2024,
  author    = {Schopen, Oliver and Narayan, Sriram and Beckmann, Marvin and Najmi, Aezid-Ul-Hassan and Esch, Thomas and Shabani, Bahman},
  title     = {An EIS approach to quantify the effects of inlet air relative humidity on the performance of proton exchange membrane fuel cells: a pathway to developing a novel fault diagnostic method},
  series = {International Journal of Hydrogen Energy},
  volume    = {58},
  journal   = {International Journal of Hydrogen Energy},
  number    = {8},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {0360-3199 (print)},
  issn      = {1879-3487 (online)},
  doi       = {10.1016/j.ijhydene.2024.01.218},
  pages     = {1302 -- 1315},
  year      = {2024},
  abstract  = {In this work, the effect of low air relative humidity on the operation of a polymer electrolyte membrane fuel cell is investigated. An innovative method through performing in situ electrochemical impedance spectroscopy is utilised to quantify the effect of inlet air relative humidity at the cathode side on internal ionic resistances and output voltage of the fuel cell. In addition, algorithms are developed to analyse the electrochemical characteristics of the fuel cell. For the specific fuel cell stack used in this study, the membrane resistance drops by over 39 \% and the cathode side charge transfer resistance decreases by 23 \% after increasing the humidity from 30 \% to 85 \%, while the results of static operation also show an increase of ∼2.2 \% in the voltage output after increasing the relative humidity from 30 \% to 85 \%. In dynamic operation, visible drying effects occur at < 50 \% relative humidity, whereby the increase of the air side stoichiometry increases the drying effects. Furthermore, other parameters, such as hydrogen humidification, internal stack structure, and operating parameters like stoichiometry, pressure, and temperature affect the overall water balance. Therefore, the optimal humidification range must be determined by considering all these parameters to maximise the fuel cell performance and durability. The results of this study are used to develop a health management system to ensure sufficient humidification by continuously monitoring the fuel cell polarisation data and electrochemical impedance spectroscopy indicators.},
  language  = {en}
}
@unpublished{SchmuellingGuetzlaffCzupalla2024,
  author    = {Schm{\"u}lling, Max and G{\"u}tzlaff, Joel and Czupalla, Markus},
  title     = {A thermal simulation environment for moving objects on the lunar surface},
  doi       = {10.21203/rs.3.rs-3902363/v1},
  pages     = {12 Seiten},
  year      = {2024},
  abstract  = {This paper presents a thermal simulation environment for moving objects on the lunar surface. The goal of the thermal simulation environment is to enable the reliable prediction of the temperature development of a given object on the lunar surface by providing the respective heat fluxes for a mission on a given travel path. The user can import any object geometry and freely define the path that the object should travel. Using the path of the object, the relevant lunar surface geometry is imported from a digital elevation model. The relevant parts of the lunar surface are determined based on distance to the defined path. A thermal model of these surface sections is generated, consisting of a porous layer on top and a denser layer below. The object is moved across the lunar surface, and its inclination is adapted depending on the slope of the terrain below it. Finally, a transient thermal analysis of the object and its environment is performed at several positions on its path and the results are visualized. The paper introduces details on the thermal modeling of the lunar surface, as well as its verification. Furthermore, the structure of the created software is presented. The robustness of the environment is verified with the help of sensitivity studies and possible improvements are presented.},
  language  = {en}
}
@article{SchopenShahEschetal.2024,
  author    = {Schopen, Oliver and Shah, Neel and Esch, Thomas and Shabani, Bahman},
  title     = {Critical quantitative evaluation of integrated health management methods for fuel cell applications},
  series = {International Journal of Hydrogen Energy},
  volume    = {70},
  journal   = {International Journal of Hydrogen Energy},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0360-3199},
  doi       = {10.1016/j.ijhydene.2024.05.156},
  pages     = {370 -- 388},
  year      = {2024},
  abstract  = {Online fault diagnostics is a crucial consideration for fuel cell systems, particularly in mobile applications, to limit downtime and degradation, and to increase lifetime. Guided by a critical literature review, in this paper an overview of Health management systems classified in a scheme is presented, introducing commonly utilised methods to diagnose FCs in various applications. In this novel scheme, various Health management system methods are summarised and structured to provide an overview of existing systems including their associated tools. These systems are classified into four categories mainly focused on model-based and non-model-based systems. The individual methods are critically discussed when used individually or combined aimed at further understanding their functionality and suitability in different applications. Additionally, a tool is introduced to evaluate methods from each category based on the scheme presented. This tool applies the technique of matrix evaluation utilising several key parameters to identify the most appropriate methods for a given application. Based on this evaluation, the most suitable methods for each specific application are combined to build an integrated Health management system.},
  language  = {en}
}
@article{Bung2024,
  author    = {Bung, Daniel Bernhard},
  title     = {Kamerabasierte Fließtiefen- und Geschwindigkeitsmessungen},
  series = {Wasserwirtschaft},
  volume    = {114},
  journal   = {Wasserwirtschaft},
  number    = {4},
  publisher = {Springer Vieweg},
  address   = {Wiesbaden},
  issn      = {0043-0978},
  pages     = {47 -- 53},
  year      = {2024},
  abstract  = {In der wasserbaulichen Forschung werden neben klassischen Messinstrumenten zunehmend kamerabasierte Verfahren genutzt. Diese erlauben neben der Bestimmung von Fließgeschwindigkeiten auch die Detektion der freien Wasseroberfl{\"a}che oder zeitliche Vermessung von Kolken. Durch die hohen r{\"a}umlichen und zeitlichen Aufl{\"o}sungen, welche neueste Kamerasensoren liefern, k{\"o}nnen neue Erkenntnisse in turbulenten, komplexen Str{\"o}mungen gewonnen werden. Auch in der Praxis k{\"o}nnen diese Verfahren mit geringem Aufwand wichtige Daten liefern.},
  language  = {de}
}
@inproceedings{KahraBreussKleefeldetal.2024,
  author    = {Kahra, Marvin and Breuß, Michael and Kleefeld, Andreas and Welk, Martin},
  title     = {An Approach to Colour Morphological Supremum Formation Using the LogSumExp Approximation},
  series = {Discrete Geometry and Mathematical Morphology},
  booktitle = {Discrete Geometry and Mathematical Morphology},
  editor    = {Brunetti, Sara and Frosini, Andrea and Rinaldi, Simone},
  publisher = {Springer},
  address   = {Cham},
  isbn      = {978-3-031-57793-2},
  doi       = {10.1007/978-3-031-57793-2_25},
  pages     = {325 -- 337},
  year      = {2024},
  abstract  = {Mathematical morphology is a part of image processing that has proven to be fruitful for numerous applications. Two main operations in mathematical morphology are dilation and erosion. These are based on the construction of a supremum or infimum with respect to an order over the tonal range in a certain section of the image. The tonal ordering can easily be realised in grey-scale morphology, and some morphological methods have been proposed for colour morphology. However, all of these have certain limitations. In this paper we present a novel approach to colour morphology extending upon previous work in the field based on the Loewner order. We propose to consider an approximation of the supremum by means of a log-sum exponentiation introduced by Maslov. We apply this to the embedding of an RGB image in a field of symmetric 2x2 matrices. In this way we obtain nearly isotropic matrices representing colours and the structural advantage of transitivity. In numerical experiments we highlight some remarkable properties of the proposed approach.},
  language  = {en}
}
@article{AyalaHarrisKleefeld2024,
  author    = {Ayala, Rafael Ceja and Harris, Isaac and Kleefeld, Andreas},
  title     = {Direct sampling method via Landweber iteration for an absorbing scatterer with a conductive boundary},
  series = {Inverse Problems and Imaging},
  volume    = {18},
  journal   = {Inverse Problems and Imaging},
  number    = {3},
  publisher = {AIMS},
  address   = {Springfield},
  issn      = {1930-8337},
  doi       = {10.3934/ipi.2023051},
  pages     = {708 -- 729},
  year      = {2024},
  abstract  = {In this paper, we consider the inverse shape problem of recovering isotropic scatterers with a conductive boundary condition. Here, we assume that the measured far-field data is known at a fixed wave number. Motivated by recent work, we study a new direct sampling indicator based on the Landweber iteration and the factorization method. Therefore, we prove the connection between these reconstruction methods. The method studied here falls under the category of qualitative reconstruction methods where an imaging function is used to recover the absorbing scatterer. We prove stability of our new imaging function as well as derive a discrepancy principle for recovering the regularization parameter. The theoretical results are verified with numerical examples to show how the reconstruction performs by the new Landweber direct sampling method.},
  language  = {en}
}
@article{ClausnitzerKleefeld2024,
  author    = {Clausnitzer, Julian and Kleefeld, Andreas},
  title     = {A spectral Galerkin exponential Euler time-stepping scheme for parabolic SPDEs on two-dimensional domains with a C² boundary},
  series = {Discrete and Continuous Dynamical Systems - Series B},
  volume    = {29},
  journal   = {Discrete and Continuous Dynamical Systems - Series B},
  number    = {4},
  publisher = {AIMS},
  address   = {Springfield},
  issn      = {1531-3492},
  doi       = {10.3934/dcdsb.2023148},
  pages     = {1624 -- 1651},
  year      = {2024},
  abstract  = {We consider the numerical approximation of second-order semi-linear parabolic stochastic partial differential equations interpreted in the mild sense which we solve on general two-dimensional domains with a C² boundary with homogeneous Dirichlet boundary conditions. The equations are driven by Gaussian additive noise, and several Lipschitz-like conditions are imposed on the nonlinear function. We discretize in space with a spectral Galerkin method and in time using an explicit Euler-like scheme. For irregular shapes, the necessary Dirichlet eigenvalues and eigenfunctions are obtained from a boundary integral equation method. This yields a nonlinear eigenvalue problem, which is discretized using a boundary element collocation method and is solved with the Beyn contour integral algorithm. We present an error analysis as well as numerical results on an exemplary asymmetric shape, and point out limitations of the approach.},
  language  = {en}
}
@article{ChwallekNawrathKrastinaetal.2024,
  author    = {Chwallek, Constanze and Nawrath, Lara and Krastina, Anzelika and Bruksle, Ieva},
  title     = {Supportive research on sustainable entrepreneurship and business practices},
  series = {SECA Sustainable Entrepreneurship for Climate Action},
  journal   = {SECA Sustainable Entrepreneurship for Climate Action},
  number    = {3},
  publisher = {Lapland University of Applied Sciences Ltd},
  address   = {Rovaniemi},
  isbn      = {978-952-316-514-4 (pdf)},
  issn      = {2954-1654 (on-line publication)},
  pages     = {67 Seiten},
  year      = {2024},
  language  = {en}
}
@techreport{HoffmannUllrich2024,
  type      = {Working Paper},
  author    = {Hoffmann, Sarah and Ullrich, Anna Valentine},
  title     = {30 Minuten FDM f{\"u}r HAW. Ein Informationsformat f{\"u}r Forschende an HAW in NRW},
  doi       = {10.5281/zenodo.12569282},
  pages     = {1 Seite},
  year      = {2024},
  abstract  = {Wie kann man das Thema Forschungsdatenmanagement (FDM) konkret und anwendbar f{\"u}r Forschende gestalten, die bisher noch wenig Kontakt damit hatten? Auf diese Frage gibt das Konzept „30 Minuten FDM f{\"u}r HAW. Ein Informationsformat f{\"u}r Forschende an HAW in NRW" eine Antwort. Es entstand als Projektarbeit im Zertifikatskurs Forschungsdatenmanagement 2023/24},
  language  = {de}
}
@techreport{BirmansSchickTamborninoetal.2024,
  type      = {Working Paper},
  author    = {Birmans, Katrin and Schick, Elena and Tambornino, Philipp and Ullrich, Anna Valentine},
  title     = {Ingenieurwissenschaften im Fokus: Zug{\"a}nge zu einem effektiven Forschungsdatenmanagement an HAW},
  doi       = {10.5281/zenodo.12545429},
  pages     = {49 Seiten},
  year      = {2024},
  abstract  = {Im Rahmen der Love Data Week vom 12. bis 16.02.2024 haben die BMBF-Projekte FDM2_TH_Koeln der TH K{\"o}ln (FK 16FDFH105) und Persist@HAW der FH Aachen (FK 16FDFH129) am 15.02.2024 gemeinsam eine Online-Veranstaltung mit dem Titel „Ingenieurwissenschaften im Fokus: Zug{\"a}nge zu einem effektiven Forschungsdatenmanagement an HAW" angeboten. Diese richtete sich an Forschende aus den Ingenieurwissenschaften, die einen ersten Zugang zum Thema Forschungsdatenmanagement (FDM) suchen und erfahren m{\"o}chten, welche speziellen Angebote f{\"u}r die Daten aus den Ingenieurwissenschaften existieren. In der Veranstaltung wurden wesentliche Aspekte des Forschungsdatenmanagements entlang des Datenlebenszyklus beleuchtet. Ziel war es, den Teilnehmenden praxisnahe Einblicke und Hilfestellungen zu einem effektiven Umgang mit Forschungsdaten an Hochschulen f{\"u}r Angewandte Wissenschaften (HAW) zu bieten. Durch Beispiele und konkrete Empfehlungen wurde das Thema zug{\"a}nglich gemacht.},
  language  = {de}
}