@masterthesis{Gros2024, type = {Bachelor Thesis}, author = {Gros, Isabella}, title = {Depressed Furniture : eine abstrakte {\"U}bersetzung von Depressionen in M{\"o}blierung}, publisher = {FH Aachen}, address = {Aachen}, school = {Fachhochschule Aachen}, pages = {367 Seiten}, year = {2024}, abstract = {Depressed Furniture ist eine abstrakte {\"U}bersetzung von Depressionen in M{\"o}blierung. Es handelt sich um eine Rauminstallation von f{\"u}nf Leuchten, die der Erkrankung in einem un{\"u}blichen Kontext eine Plattform gibt. Dadurch stellt das Projekt eine Schnittstelle zwischen Kunst, Design und Gesellschaft dar. Jede Leuchte verk{\"o}rpert eine Empfindung, mit der sich ein Großteil der Betroffenen identifizieren kann. Es wird Bewusstsein f{\"u}r die Komplexit{\"a}t der Krankheit geschaffen und das Tabu um mentale Krankheiten gebrochen. Neben der Regular Collection k{\"o}nnen auch Tischvarianten (Compact Collection) erworben werden. Depressed Furniture zeigt, dass es durchaus m{\"o}glich ist, eine unsch{\"o}ne Thematik zu abstrahieren und ihr neutral zu begegnen. Es verdeutlicht, wie Design dazu beitragen kann, sensible Themen auf kreative Weise zu kommunizieren.}, language = {de} } @article{OezsoyluAliaziziWagneretal.2024, author = {{\"O}zsoylu, Dua and Aliazizi, Fereshteh and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Template bacteria-free fabrication of surface imprinted polymer-based biosensor for E. coli detection using photolithographic mimics: Hacking bacterial adhesion}, series = {Biosensors and Bioelectronics}, volume = {261}, journal = {Biosensors and Bioelectronics}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-4235 (eISSN)}, doi = {10.1016/j.bios.2024.116491}, pages = {11 Seiten}, year = {2024}, abstract = {As one class of molecular imprinted polymers (MIPs), surface imprinted polymer (SIP)-based biosensors show great potential in direct whole-bacteria detection. Micro-contact imprinting, that involves stamping the template bacteria immobilized on a substrate into a pre-polymerized polymer matrix, is the most straightforward and prominent method to obtain SIP-based biosensors. However, the major drawbacks of the method arise from the requirement for fresh template bacteria and often non-reproducible bacteria distribution on the stamp substrate. Herein, we developed a positive master stamp containing photolithographic mimics of the template bacteria (E. coli) enabling reproducible fabrication of biomimetic SIP-based biosensors without the need for the "real" bacteria cells. By using atomic force and scanning electron microscopy imaging techniques, respectively, the E. coli-capturing ability of the SIP samples was tested, and compared with non-imprinted polymer (NIP)-based samples and control SIP samples, in which the cavity geometry does not match with E. coli cells. It was revealed that the presence of the biomimetic E. coli imprints with a specifically designed geometry increases the sensor E. coli-capturing ability by an "imprinting factor" of about 3. These findings show the importance of geometry-guided physical recognition in bacterial detection using SIP-based biosensors. In addition, this imprinting strategy was employed to interdigitated electrodes and QCM (quartz crystal microbalance) chips. E. coli detection performance of the sensors was demonstrated with electrochemical impedance spectroscopy (EIS) and QCM measurements with dissipation monitoring technique (QCM-D).}, language = {en} } @article{TixMollKrafftetal.2024, author = {Tix, Julian and Moll, Fabian and Krafft, Simone and Betsch, Matthias and Tippk{\"o}tter, Nils}, title = {Hydrogen production from enzymatic pretreated organic waste with thermotoga neapolitana}, series = {Energies}, volume = {17}, journal = {Energies}, number = {12}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {10.3390/en17122938}, pages = {20 Seiten}, year = {2024}, abstract = {Biomass from various types of organic waste was tested for possible use in hydrogen production. The composition consisted of lignified samples, green waste, and kitchen scraps such as fruit and vegetable peels and leftover food. For this purpose, the enzymatic pretreatment of organic waste with a combination of five different hydrolytic enzymes (cellulase, amylase, glucoamylase, pectinase and xylase) was investigated to determine its ability to produce hydrogen (H2) with the hydrolyzate produced here. In course, the anaerobic rod-shaped bacterium T. neapolitana was used for H2 production. First, the enzymes were investigated using different substrates in preliminary experiments. Subsequently, hydrolyses were carried out using different types of organic waste. In the hydrolysis carried out here for 48 h, an increase in glucose concentration of 481\% was measured for waste loads containing starch, corresponding to a glucose concentration at the end of hydrolysis of 7.5 g·L-1. In the subsequent set fermentation in serum bottles, a H2 yield of 1.26 mmol H2 was obtained in the overhead space when Terrific Broth Medium with glucose and yeast extract (TBGY medium) was used. When hydrolyzed organic waste was used, even a H2 yield of 1.37 mmol could be achieved in the overhead space. In addition, a dedicated reactor system for the anaerobic fermentation of T. neapolitana to produce H2 was developed. The bioreactor developed here can ferment anaerobically with a very low loss of produced gas. Here, after 24 h, a hydrogen concentration of 83\% could be measured in the overhead space.}, language = {en} } @masterthesis{Pauls2024, type = {Bachelor Thesis}, author = {Pauls, Benjamin}, title = {Energiewende im Stromsektor: Nachhaltigkeit {\"u}ber Umweltschutz hinaus}, school = {Fachhochschule Aachen}, pages = {IV, 88 Seiten}, year = {2024}, abstract = {Die Energiewende wird h{\"a}ufig als „nachhaltig" bezeichnet, das genaue Begriffsverst{\"a}ndnis bleibt jedoch vage. Diese Transformation von fossilen und nuklearen hin zu erneuerbaren Energiequellen steht im Fokus der Treibhausgasneutralit{\"a}t. So soll dem fortschreitenden Klimawandel entgegengetreten werden. Das Thema der vorliegenden Arbeit ist die Definition eines m{\"o}glichen Verst{\"a}ndnisses von „Nachhaltigkeit" in der Energiewende des deutschen Stromsektors. Die leitenden Forschungsfragen lauten: Was kann im Zusammenhang mit der Energiewende im Stromsektor Deutschlands unter Nachhaltigkeit verstanden werden? Inwieweit unterscheidet sich dieses Verst{\"a}ndnis von der bisherigen Herangehensweise? Die Datenbasis zur Beantwortung dieser liefern sechs leitfadengest{\"u}tzte Expert:inneninterviews. Als Analysemethode dient die inhaltliche Strukturierung nach Mayring (2015). Die qualitative Studie hat gezeigt, dass eine nachhaltige Energiewende den Menschen und die Natur zentralisiert. Weiter aufgeschl{\"u}sselt stehen die drei Nachhaltigkeitsdimensionen und die Generationengerechtigkeit. Dabei dient die {\"o}konomische Dimension der sozialen und {\"o}kologischen. Wichtig sind die Inklusion und Beteiligung von Bev{\"o}lkerung, Unternehmen und Politik. Gleichzeitig ist sie Herausforderung und Chance f{\"u}r einen positiven gesellschaftlichen Wandel. Technisch dienen Windenergie- und Photovoltaikanlagen als Energielieferanten und Wasserstoffsysteme als Zwischenspeicher, Stabilit{\"a}tssicherung und zur Kopplung der Sektoren. Damit ist Nachhaltigkeit die Chance, die Energiewende richtig zu gestalten und damit {\"u}ber Klimaneutralit{\"a}t hinauszugehen}, language = {de} } @article{ThomaGardiFisheretal.2024, author = {Thoma, Andreas and Gardi, Alessandro and Fisher, Alex and Braun, Carsten}, title = {Improving local path planning for UAV flight in challenging environments by refining cost function weights}, series = {CEAS Aeronautical Journal}, journal = {CEAS Aeronautical Journal}, publisher = {Springer}, address = {Wien}, issn = {1869-5590 (eISSN)}, doi = {10.1007/s13272-024-00741-x}, pages = {12 Seiten}, year = {2024}, abstract = {Unmanned Aerial Vehicles (UAV) constantly gain in versatility. However, more reliable path planning algorithms are required until full autonomous UAV operation is possible. This work investigates the algorithm 3DVFH* and analyses its dependency on its cost function weights in 2400 environments. The analysis shows that the 3DVFH* can find a suitable path in every environment. However, a particular type of environment requires a specific choice of cost function weights. For minimal failure, probability interdependencies between the weights of the cost function have to be considered. This dependency reduces the number of control parameters and simplifies the usage of the 3DVFH*. Weights for costs associated with vertical evasion (pitch cost) and vicinity to obstacles (obstacle cost) have the highest influence on the failure probability of the local path planner. Environments with mainly very tall buildings (like large American city centres) require a preference for horizontal avoidance manoeuvres (achieved with high pitch cost weights). In contrast, environments with medium-to-low buildings (like European city centres) benefit from vertical avoidance manoeuvres (achieved with low pitch cost weights). The cost of the vicinity to obstacles also plays an essential role and must be chosen adequately for the environment. Choosing these two weights ideal is sufficient to reduce the failure probability below 10\%.}, language = {en} } @article{MoehrenBergmannJanseretal.2024, author = {M{\"o}hren, Felix and Bergmann, Ole and Janser, Frank and Braun, Carsten}, title = {Assessment of structural mechanical effects related to torsional deformations of propellers}, series = {CEAS Aeronautical Journal}, journal = {CEAS Aeronautical Journal}, publisher = {Springer}, address = {Wien}, issn = {1869-5590 (eISSN)}, doi = {10.1007/s13272-024-00737-7}, pages = {22 Seiten}, year = {2024}, abstract = {Lifting propellers are of increasing interest for Advanced Air Mobility. All propellers and rotors are initially twisted beams, showing significant extension-twist coupling and centrifugal twisting. Torsional deformations severely impact aerodynamic performance. This paper presents a novel approach to assess different reasons for torsional deformations. A reduced-order model runs large parameter sweeps with algebraic formulations and numerical solution procedures. Generic beams represent three different propeller types for General Aviation, Commercial Aviation, and Advanced Air Mobility. Simulations include solid and hollow cross-sections made of aluminum, steel, and carbon fiber-reinforced polymer. The investigation shows that centrifugal twisting moments depend on both the elastic and initial twist. The determination of the centrifugal twisting moment solely based on the initial twist suffers from errors exceeding 5\% in some cases. The nonlinear parts of the torsional rigidity do not significantly impact the overall torsional rigidity for the investigated propeller types. The extension-twist coupling related to the initial and elastic twist in combination with tension forces significantly impacts the net cross-sectional torsional loads. While the increase in torsional stiffness due to initial twist contributes to the overall stiffness for General and Commercial Aviation propellers, its contribution to the lift propeller's stiffness is limited. The paper closes with the presentation of approximations for each effect identified as significant. Numerical evaluations are necessary to determine each effect for inhomogeneous cross-sections made of anisotropic material.}, language = {en} } @article{AdelsMonakhova2024, author = {Adels, Klaudia and Monakhova, Yulia}, title = {Low-field NMR spectroscopic study of e-cigarettes: Is determination of only nicotine and organic carrier solvents possible?}, series = {Microchemical Journal}, volume = {203}, journal = {Microchemical Journal}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1095-9149}, doi = {10.1016/j.microc.2024.110859}, pages = {9 Seiten}, year = {2024}, abstract = {Electronic cigarettes (e-cigarettes) have become popular worldwide with the market growing exponentially in some countries. The absence of product standards and safety regulations requires urgent development of analytical methodologies for the holistic control of the growing diversity of such products. An approach based on low-field nuclear magnetic resonance (LF-NMR) at 80 MHz is presented for the simultaneous determination of key parameters: carrier solvents (vegetable glycerine (VG), propylene glycol (PG) and water), total nicotine as well as free-base nicotine fraction. Moreover, qualitative and quantitative determination of fourteen weak organic acids deliberately added to enhance sensory characteristics of e-cigarettes was possible. In most cases these parameters can be rapidly and conveniently determined without using any sample manipulation such as dilution, extraction or derivatization steps. The method was applied for 37 authentic e-cigarettes samples. In particular, eight different organic acids with the content up to 56 mg/mL were detected. Due to its simplicity, the method can be used in routine regulatory control as well as to study release behaviour of nicotine and other e-cigarettes constituents in different products.}, language = {en} } @techreport{Drescher2018, type = {Working Paper}, author = {Drescher, Hans Paul}, title = {The irreversible thermodynamic's theorem of minimum entropy production applied to the laminar and the turbulent Couette flow}, pages = {48 Seiten}, year = {2018}, abstract = {Analyzing thermodynamic non-equilibrium processes, like the laminar and turbulent fluid flow, the dissipation is a key parameter with a characteristic minimum condition. That is applied to characterize laminar and turbulent behaviour of the Couette flow, including its transition in both directions. The Couette flow is chosen as the only flow form with constant shear stress over the flow profile, being laminar, turbulent or both. The local dissipation defines quantitative and stable criteria for the transition and the existence of turbulence. There are basic results: The Navier Stokes equations cannot describe the experimental flow profiles of the turbulent Couette flow. But they are used to quantify the dissipation of turbulent fluctuation. The dissipation minimum requires turbulent structures reaching maximum macroscopic dimensions, describing turbulence as a "non-local" phenomenon. At the transition the Couette flow profiles and the shear stress change by a factor ≅ 5 due to a change of the "apparent" turbulent viscosity by a calculated factor ≅ 27. The resulting difference of the laminar and the turbulent profiles results in two different Reynolds numbers and different loci of transition, which are identified by calculation.}, language = {en} } @techreport{Drescher2021, type = {Working Paper}, author = {Drescher, Hans Paul}, title = {Turbulence - minimum dissipation and maximum macroscopic momentum exchange}, pages = {44 Seiten}, year = {2021}, abstract = {The minimum dissipation requirement of the thermodynamics of irreversible processes is applied to characterize the existence of laminar and non-laminar, and the co-existence of laminar and turbulent flow zones. Local limitations of the different zones and three different forms of transition are defined. For the Couette flow a non-local "corpuscular" flow mechanism explains the logarithmic law-of-the-wall, maximum turbulent dimensions and a value x=0,415 for the v. K{\´a}rm{\´a}n constant. Limitations of the logarithmic law near the wall and in the centre of the experiment are interpreted.}, language = {en} } @masterthesis{Lambertus2024, type = {Bachelor Thesis}, author = {Lambertus, Jan-Michael}, title = {CardboardCastle}, publisher = {FH Aachen}, address = {Aachen}, school = {Fachhochschule Aachen}, pages = {60 Seiten}, year = {2024}, abstract = {„CardboardCastle" ist ein 3D-Animationsfilm. Der Film zeigt die lebendig gewordene Welt zweier K{\"o}nigreiche aus Pappe, die in einem Streit um einen magischen Zauberstab verwickelt sind. Das Projekt beweist, dass es m{\"o}glich ist, mit der Software „Blender" einen vollwertigen und hochwertigen 3D-Animationsfilm zu erstellen. Dabei wurden alle Assets bis auf Texturen selbst hergestellt. Die virtuelle Pappe spielt hierbei eine fundamentale Rolle, f{\"u}r diese wurde ein vollkommen neuer Workflow entwickelt, welcher es erm{\"o}glicht, realistische Pappe zu visualisieren. „CardboardCastle" setzt auf eine cinematische Inszenierung von Licht und vereint technisches Wissen mit unterhaltenden Inhalten. Dabei zeigt er die kindliche Vorstellungskraft und l{\"a}dt die Zuschauer ein, sich an ihre eigenen kindlichen Fantasien zu erinnern.}, language = {de} }