@article{ValeroBungErpicumetal.2022, author = {Valero, Daniel and Bung, Daniel Bernhard and Erpicum, Sebastien and Peltier, Yann and Dewals, Benjamin}, title = {Unsteady shallow meandering flows in rectangular reservoirs: a modal analysis of URANS modelling}, series = {Journal of Hydro-environment Research}, journal = {Journal of Hydro-environment Research}, number = {In Press}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1570-6443}, doi = {10.1016/j.jher.2022.03.002}, year = {2022}, abstract = {Shallow flows are common in natural and human-made environments. Even for simple rectangular shallow reservoirs, recent laboratory experiments show that the developing flow fields are particularly complex, involving large-scale turbulent structures. For specific combinations of reservoir size and hydraulic conditions, a meandering jet can be observed. While some aspects of this pseudo-2D flow pattern can be reproduced using a 2D numerical model, new 3D simulations, based on the unsteady Reynolds-Averaged Navier-Stokes equations, show consistent advantages as presented herein. A Proper Orthogonal Decomposition was used to characterize the four most energetic modes of the meandering jet at the free surface level, allowing comparison against experimental data and 2D (depth-averaged) numerical results. Three different isotropic eddy viscosity models (RNG k-ε, k-ε, k-ω) were tested. The 3D models accurately predicted the frequency of the modes, whereas the amplitudes of the modes and associated energy were damped for the friction-dominant cases and augmented for non-frictional ones. The performance of the three turbulence models remained essentially similar, with slightly better predictions by RNG k-ε model in the case with the highest Reynolds number. Finally, the Q-criterion was used to identify vortices and study their dynamics, assisting on the identification of the differences between: i) the three-dimensional phenomenon (here reproduced), ii) its two-dimensional footprint in the free surface (experimental observations) and iii) the depth-averaged case (represented by 2D models).}, language = {en} } @misc{VarrialeKukaTippkoetteretal.2022, author = {Varriale, Ludovica and Kuka, Katrin and Tippk{\"o}tter, Nils and Ulber, Roland}, title = {Use of a green biomass in a biorefinery platform}, series = {Chemie Ingenieur Technik}, volume = {94}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.202255095}, pages = {1299}, year = {2022}, abstract = {The emerging environmental issues due to the use of fossil resources are encouraging the exploration of new renewable resources. Biomasses are attracting more interest due to the low environmental impacts, low costs, and high availability on earth. In this scenario, green biorefineries are a promising platform in which green biomasses are used as feedstock. Grasses are mainly composed of cellulose and hemicellulose, and lignin is available in a small amount. In this work, a perennial ryegrass was used as feedstock to develop a green bio-refinery platform. Firstly, the grass was mechanically pretreated, thus obtaining a press juice and a press cake fraction. The press juice has high nutritional values and can be employed as part of fermentation media. The press cake can be employed as a substrate either in enzymatic hydrolysis or in solid-state fermentation. The overall aim of this work was to demonstrate different applications of both the liquid and the solid fractions. For this purpose, the filamentous fungus A. niger and the yeast Y. lipolythica were selected for their ability to produce citric acid. Finally, the possibility was assessed to use the press juice as part of fermentation media to cultivate S. cerevisiae and lactic acid bacteria for ethanol and lactic acid fermentation.}, language = {en} } @inproceedings{VeettilRakshitSchopenetal.2022, author = {Veettil, Yadu Krishna Morassery and Rakshit, Shantam and Schopen, Oliver and Kemper, Hans and Esch, Thomas and Shabani, Bahman}, title = {Automated Control System Strategies to Ensure Safety of PEM Fuel Cells Using Kalman Filters}, series = {Proceedings of the 7th International Conference and Exhibition on Sustainable Energy and Advanced Materials (ICE-SEAM 2021), Melaka, Malaysia}, booktitle = {Proceedings of the 7th International Conference and Exhibition on Sustainable Energy and Advanced Materials (ICE-SEAM 2021), Melaka, Malaysia}, editor = {Bin Abdollah, Mohd Fadzli and Amiruddin, Hilmi and Singh, Amrik Singh Phuman and Munir, Fudhail Abdul and Ibrahim, Asriana}, publisher = {Springer Nature}, address = {Singapore}, isbn = {978-981-19-3178-9}, issn = {2195-4356}, doi = {10.1007/978-981-19-3179-6_55}, pages = {296 -- 299}, year = {2022}, abstract = {Having well-defined control strategies for fuel cells, that can efficiently detect errors and take corrective action is critically important for safety in all applications, and especially so in aviation. The algorithms not only ensure operator safety by monitoring the fuel cell and connected components, but also contribute to extending the health of the fuel cell, its durability and safe operation over its lifetime. While sensors are used to provide peripheral data surrounding the fuel cell, the internal states of the fuel cell cannot be directly measured. To overcome this restriction, Kalman Filter has been implemented as an internal state observer. Other safety conditions are evaluated using real-time data from every connected sensor and corrective actions automatically take place to ensure safety. The algorithms discussed in this paper have been validated thorough Model-in-the-Loop (MiL) tests as well as practical validation at a dedicated test bench.}, language = {en} } @misc{Vogt2022, type = {Master Thesis}, author = {Vogt, Lena}, title = {Arch{\"a}ologischer Restaurator : Ausstellungskonzept R{\"o}misch-Germanisches Museum K{\"o}ln}, publisher = {FH Aachen}, address = {Aachen}, pages = {23 Seiten}, year = {2022}, abstract = {Alte, geschichtsrelevante und thematisch angeordnete Objekte, welche man in den Vitrinen der Museen betrachten kann, das kennt sicher jeder. Doch wie kommen diese Artefakte eigentlich in die Vitrinen? Welche Menschen sind daf{\"u}r verantwortlich, dass wir diese Kulturg{\"u}ter bestaunen k{\"o}nnen? In diesem tempor{\"a}ren Ausstellungskonzept f{\"u}r das R{\"o}misch-Germanische Museum K{\"o}ln geht es darum, die sonst verborgene Arbeit der Restauratoren des Museums f{\"u}r die Besucher:innen sichtbar zu machen, ihnen genauere Einblicke in die Arbeit mit ihren Anforderungen zu geben und Restaurierungsprozesse auf zu zeigen. Diese Arbeit demonstriert, wie es abseits der {\"O}ffentlichkeit aussieht und wer daf{\"u}r verantwortlich ist, dass wir einen Einblick in die vergangenen Zeit erhalten k{\"o}nnen. Das Projekt zeigt eine m{\"o}gliche Bespielung des Museums, wie das Berufsbild der Restauratoren in die Dauerausstellung integriert werden k{\"o}nnte.}, language = {de} } @article{vonHaefenKrautwaldStolleetal.2022, author = {von H{\"a}fen, Hajo and Krautwald, Clemens and Stolle, Jacob and Bung, Daniel Bernhard and Goseberg, Nils}, title = {Overland flow of broken solitary waves over a two-dimensional coastal plane}, series = {Coastal Engineering}, volume = {175}, journal = {Coastal Engineering}, number = {August}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1872-7379}, doi = {10.1016/j.coastaleng.2022.104125}, pages = {14 Seiten}, year = {2022}, abstract = {Landslides, rock falls or related subaerial and subaqueous mass slides can generate devastating impulse waves in adjacent waterbodies. Such waves can occur in lakes and fjords, or due to glacier calving in bays or at steep ocean coastlines. Infrastructure and residential houses along coastlines of those waterbodies are often situated on low elevation terrain, and are potentially at risk from inundation. Impulse waves, running up a uniform slope and generating an overland flow over an initially dry adjacent horizontal plane, represent a frequently found scenario, which needs to be better understood for disaster planning and mitigation. This study presents a novel set of large-scale flume test focusing on solitary waves propagating over a 1:14.5 slope and breaking onto a horizontal section. Examining the characteristics of overland flow, this study gives, for the first time, insight into the fundamental process of overland flow of a broken solitary wave: its shape and celerity, as well as its momentum when wave breaking has taken place beforehand.}, language = {en} } @masterthesis{Vornewald2022, type = {Bachelor Thesis}, author = {Vornewald, Klara Franziska}, title = {Graphic Novel : Konzeptionierung und Umsetzung einer Graphic Novel f{\"u}r Kinder}, publisher = {FH Aachen}, address = {Aachen}, pages = {147 Seiten}, year = {2022}, abstract = {Die Graphic Novel „Traumspiel" erz{\"a}hlt eine kindgerechte Fantasiegeschichte zum Thema Traum. Ansatz des Projektes war die Frage, wie wohl eine Welt auss{\"a}he, in der Tr{\"a}ume eine greifbare Entit{\"a}t darstellen. Ziel war es, diese Welt und eine dort spielende Geschichte zu erschaffen und beides visuell in einer Graphic Novel zum Leben zu erwecken. In „Traumspiel" werden Menschen unwissentlich nachts in ein Traumland entf{\"u}hrt, wo ihnen die Tr{\"a}ume als Marionettentheater vorgespielt werden. Erz{\"a}hlt wird die Geschichte eines Kindes, das auf diese Weise je einen Traum und Albtraum erlebt. Die Illustrationen sind mit Tusche gemalt. Durch die Beschr{\"a}nkung auf drei Farben werden verschiedene Aspekte der Geschichte visuell unterschieden. Entstanden ist eine Graphic Novel, in der alle konzeptionellen und gestalterischen Entscheidungen aufeinander aufbauen, um eine spannende Geschichte zu erz{\"a}hlen.}, language = {de} } @masterthesis{Voth2022, type = {Bachelor Thesis}, author = {Voth, Emily}, title = {KiWA : Die Garderobe f{\"u}r kleine Selbstst{\"a}ndige}, publisher = {FH Aachen}, address = {Aachen}, pages = {117 Seiten}, year = {2022}, abstract = {Kindertagesst{\"a}tten bieten Kleinkindern den Zugang zu unbeschwertem und spielerischem Lernen. Was also, wenn schon der Eingangsbereich die Reiz{\"u}berflutung bereit h{\"a}lt, der Stauraum der Entfaltung der Kinder nicht gerecht wird und ihre Eigenst{\"a}ndigkeit ungef{\"o}rdert bleibt? Es kommt zu unzufriedenen Kindern und Frustration aller Beteilligten. "KIWA" ist das Garderobensystem f{\"u}r Kinder zur St{\"a}rkung der heranwachsenden Selbstst{\"a}ndigkeit. Mithilfe von pers{\"o}nlichen Wiedererkennungsmerkmalen wird Eigenverantwortung geschult. Leicht und sicher zu erreichender Stauraum sorgt f{\"u}r Ordnung. Spielerisches lernen trotz Ordnung.}, language = {de} } @incollection{WeberBomholtButenweg2022, author = {Weber, Felix and Bomholt, Frederik and Butenweg, Christoph}, title = {Erdbeben- und Schwingungsschutz von Bauwerken}, series = {2023 BetonKalender: Wasserundurchl{\"a}ssiger Beton, Br{\"u}ckenbau}, booktitle = {2023 BetonKalender: Wasserundurchl{\"a}ssiger Beton, Br{\"u}ckenbau}, editor = {Bergmeister, Konrad and Fingerloos, Frank and W{\"o}rner, Johann-Dietrich}, publisher = {Ernst \& Sohn}, address = {Berlin}, isbn = {9783433611180}, doi = {10.1002/9783433611180.ch16}, pages = {779 -- 859}, year = {2022}, abstract = {Dieser Beitrag beschreibt die herk{\"o}mmlichen Maßnahmen wie die Kapazit{\"a}tsbemessung der Tragwerksstruktur, die Isolation des Bauwerks mittels Basisisolatoren, die D{\"a}mpfungserh{\"o}hung der Struktur mittels Inter-Story-D{\"a}mpfern und die Schwingungsreduktion mittels Schwingungstilgern gegen Einwirkungen durch Erdbeben, Wind, Verkehr und Personen auf die Bauwerke. Erg{\"a}nzend wird die erdbebengerechte Auslegung und Isolation von nichttragenden Bauteilen behandelt. F{\"u}r die betrachteten Systeme werden die Bewegungsdifferenzialgleichungen unter Ber{\"u}cksichtigung der wesentlichen Nichtlinearit{\"a}ten angegeben. Die vorgestellten Weiterentwicklungen in den Bereichen der Basisisolatoren, D{\"a}mpfern und Schwingungstilgern zeigen, dass das modellbasierte Design mittels Simulation ein sehr effektives, {\"o}konomisches und dank der heutigen Computerleistung auch zeiteffizientes Werkzeug darstellt.}, language = {de} } @inproceedings{WeissHeslenfeldSaeweetal.2022, author = {Weiss, Christian and Heslenfeld, Jonas and Saewe, Jasmin Kathrin and Bremen, Sebastian and H{\"a}fner, Constantin Leon}, title = {Investigation on the influence of powder humidity in Laser Powder Bed Fusion (LPBF)}, series = {Procedia CIRP 12th CIRP Conference on Photonic Technologies [LANE 2022]}, volume = {111}, booktitle = {Procedia CIRP 12th CIRP Conference on Photonic Technologies [LANE 2022]}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2212-8271}, doi = {10.1016/j.procir.2022.08.102}, pages = {115 -- 120}, year = {2022}, abstract = {In the Laser Powder Bed Fusion (LPBF) process, parts are built out of metal powder material by exposure of a laser beam. During handling operations of the powder material, several influencing factors can affect the properties of the powder material and therefore directly influence the processability during manufacturing. Contamination by moisture due to handling operations is one of the most critical aspects of powder quality. In order to investigate the influences of powder humidity on LPBF processing, four materials (AlSi10Mg, Ti6Al4V, 316L and IN718) are chosen for this study. The powder material is artificially humidified, subsequently characterized, manufactured into cubic samples in a miniaturized process chamber and analyzed for their relative density. The results indicate that the processability and reproducibility of parts made of AlSi10Mg and Ti6Al4V are susceptible to humidity, while IN718 and 316L are barely influenced.}, language = {en} } @article{WeldenPoghossianVahidpouretal.2022, author = {Welden, Melanie and Poghossian, Arshak and Vahidpour, Farnoosh and Wendlandt, Tim and Keusgen, Michael and Wege, Christina and Sch{\"o}ning, Michael Josef}, title = {Towards multi-analyte detection with field-effect capacitors modified with tobacco mosaic virus bioparticles as enzyme nanocarriers}, series = {Biosensors}, volume = {12}, journal = {Biosensors}, number = {1}, publisher = {MDPI}, address = {Basel}, issn = {2079-6374}, doi = {10.3390/bios12010043}, pages = {Artikel 43}, year = {2022}, abstract = {Utilizing an appropriate enzyme immobilization strategy is crucial for designing enzyme-based biosensors. Plant virus-like particles represent ideal nanoscaffolds for an extremely dense and precise immobilization of enzymes, due to their regular shape, high surface-to-volume ratio and high density of surface binding sites. In the present work, tobacco mosaic virus (TMV) particles were applied for the co-immobilization of penicillinase and urease onto the gate surface of a field-effect electrolyte-insulator-semiconductor capacitor (EISCAP) with a p-Si-SiO₂-Ta₂O₅ layer structure for the sequential detection of penicillin and urea. The TMV-assisted bi-enzyme EISCAP biosensor exhibited a high urea and penicillin sensitivity of 54 and 85 mV/dec, respectively, in the concentration range of 0.1-3 mM. For comparison, the characteristics of single-enzyme EISCAP biosensors modified with TMV particles immobilized with either penicillinase or urease were also investigated. The surface morphology of the TMV-modified Ta₂O₅-gate was analyzed by scanning electron microscopy. Additionally, the bi-enzyme EISCAP was applied to mimic an XOR (Exclusive OR) enzyme logic gate.}, language = {en} }