TY - JOUR A1 - Funke, Harald A1 - Esch, Thomas A1 - Roosen, Petra T1 - Powertrain Adaptions for LPG Usage in General Aviation JF - MTZ worldwide N2 - In general aviation, too, it is desirable to be able to operate existing internal combustion engines with fuels that produce less CO₂ than Avgas 100LL being widely used today It can be assumed that, in comparison, the fuels CNG, LPG or LNG, which are gaseous under normal conditions, produce significantly lower emissions. Necessary propulsion system adaptations were investigated as part of a research project at Aachen University of Applied Sciences. Y1 - 2022 U6 - https://doi.org/10.1007/s38313-021-0756-6 VL - 2022 IS - 83 SP - 58 EP - 62 PB - Springer Nature CY - Basel ER - TY - JOUR A1 - Peere, Wouter A1 - Blanke, Tobias ED - Vernon, Chris T1 - GHEtool: An open-source tool for borefield sizing in Python JF - Journal of Open Source Software N2 - GHEtool is a Python package that contains all the functionalities needed to deal with borefield design. It is developed for both researchers and practitioners. The core of this package is the automated sizing of borefield under different conditions. The sizing of a borefield is typically slow due to the high complexity of the mathematical background. Because this tool has a lot of precalculated data, GHEtool can size a borefield in the order of tenths of milliseconds. This sizing typically takes the order of minutes. Therefore, this tool is suited for being implemented in typical workflows where iterations are required. GHEtool also comes with a graphical user interface (GUI). This GUI is prebuilt as an exe-file because this provides access to all the functionalities without coding. A setup to install the GUI at the user-defined place is also implemented and available at: https://www.mech.kuleuven.be/en/tme/research/thermal_systems/tools/ghetool. KW - geothermal KW - energy KW - borefields KW - sizing Y1 - 2022 U6 - https://doi.org/10.21105/joss.04406 SN - 2475-9066 VL - 7 IS - 76 SP - 1 EP - 4, 4406 ER - TY - JOUR A1 - Gaigall, Daniel A1 - Gerstenberg, Julian T1 - Cramér-von-Mises tests for the distribution of the excess over a confidence level JF - Journal of Nonparametric Statistics N2 - The Cramér-von-Mises distance is applied to the distribution of the excess over a confidence level. Asymptotics of related statistics are investigated, and it is seen that the obtained limit distributions differ from the classical ones. For that reason, quantiles of the new limit distributions are given and new bootstrap techniques for approximation purposes are introduced and justified. The results motivate new one-sample goodness-of-fit tests for the distribution of the excess over a confidence level and a new confidence interval for the related fitting error. Simulation studies investigate size and power of the tests as well as coverage probabilities of the confidence interval in the finite sample case. A practice-oriented application of the Cramér-von-Mises tests is the determination of an appropriate confidence level for the fitting approach. The adoption of the idea to the well-known problem of threshold detection in the context of peaks over threshold modelling is sketched and illustrated by data examples. KW - Cramér-von-Mises test KW - conditional excess distribution KW - confidence interval KW - goodness-of-fit test Y1 - 2023 U6 - https://doi.org/10.1080/10485252.2023.2173958 SN - 1048-5252 (Print) SN - 1029-0311 (Online) PB - Taylor & Francis ER - TY - JOUR A1 - Liphardt, Anna-Maria A1 - Fernandez-Gonzalo, Rodrigo A1 - Albracht, Kirsten A1 - Rittweger, Jörn A1 - Vico, Laurence T1 - Musculoskeletal research in human space flight – unmet needs for the success of crewed deep space exploration JF - npj Microgravity N2 - Based on the European Space Agency (ESA) Science in Space Environment (SciSpacE) community White Paper “Human Physiology – Musculoskeletal system”, this perspective highlights unmet needs and suggests new avenues for future studies in musculoskeletal research to enable crewed exploration missions. The musculoskeletal system is essential for sustaining physical function and energy metabolism, and the maintenance of health during exploration missions, and consequently mission success, will be tightly linked to musculoskeletal function. Data collection from current space missions from pre-, during-, and post-flight periods would provide important information to understand and ultimately offset musculoskeletal alterations during long-term spaceflight. In addition, understanding the kinetics of the different components of the musculoskeletal system in parallel with a detailed description of the molecular mechanisms driving these alterations appears to be the best approach to address potential musculoskeletal problems that future exploratory-mission crew will face. These research efforts should be accompanied by technical advances in molecular and phenotypic monitoring tools to provide in-flight real-time feedback. Y1 - 2023 U6 - https://doi.org/10.1038/s41526-023-00258-3 SN - 2373-8065 VL - 9 IS - Article number: 9 SP - 1 EP - 9 PB - Springer Nature ER - TY - JOUR A1 - Ringers, Christa A1 - Bialonski, Stephan A1 - Ege, Mert A1 - Solovev, Anton A1 - Hansen, Jan Niklas A1 - Jeong, Inyoung A1 - Friedrich, Benjamin M. A1 - Jurisch-Yaksi, Nathalie T1 - Novel analytical tools reveal that local synchronization of cilia coincides with tissue-scale metachronal waves in zebrafish multiciliated epithelia JF - eLife N2 - Motile cilia are hair-like cell extensions that beat periodically to generate fluid flow along various epithelial tissues within the body. In dense multiciliated carpets, cilia were shown to exhibit a remarkable coordination of their beat in the form of traveling metachronal waves, a phenomenon which supposedly enhances fluid transport. Yet, how cilia coordinate their regular beat in multiciliated epithelia to move fluids remains insufficiently understood, particularly due to lack of rigorous quantification. We combine experiments, novel analysis tools, and theory to address this knowledge gap. To investigate collective dynamics of cilia, we studied zebrafish multiciliated epithelia in the nose and the brain. We focused mainly on the zebrafish nose, due to its conserved properties with other ciliated tissues and its superior accessibility for non-invasive imaging. We revealed that cilia are synchronized only locally and that the size of local synchronization domains increases with the viscosity of the surrounding medium. Even though synchronization is local only, we observed global patterns of traveling metachronal waves across the zebrafish multiciliated epithelium. Intriguingly, these global wave direction patterns are conserved across individual fish, but different for left and right noses, unveiling a chiral asymmetry of metachronal coordination. To understand the implications of synchronization for fluid pumping, we used a computational model of a regular array of cilia. We found that local metachronal synchronization prevents steric collisions, i.e., cilia colliding with each other, and improves fluid pumping in dense cilia carpets, but hardly affects the direction of fluid flow. In conclusion, we show that local synchronization together with tissue-scale cilia alignment coincide and generate metachronal wave patterns in multiciliated epithelia, which enhance their physiological function of fluid pumping. Y1 - 2023 U6 - https://doi.org/10.7554/eLife.77701 SN - 2050-084X VL - 12 PB - eLife Sciences Publications ER - TY - JOUR A1 - Bergmann, Ole A1 - Möhren, Felix A1 - Braun, Carsten A1 - Janser, Frank T1 - On the influence of elasticity on swept propeller noise JF - AIAA SCITECH 2023 Forum N2 - High aerodynamic efficiency requires propellers with high aspect ratios, while propeller sweep potentially reduces noise. Propeller sweep and high aspect ratios increase elasticity and coupling of structural mechanics and aerodynamics, affecting the propeller performance and noise. Therefore, this paper analyzes the influence of elasticity on forward-swept, backward-swept, and unswept propellers in hover conditions. A reduced-order blade element momentum approach is coupled with a one-dimensional Timoshenko beam theory and Farassat's formulation 1A. The results of the aeroelastic simulation are used as input for the aeroacoustic calculation. The analysis shows that elasticity influences noise radiation because thickness and loading noise respond differently to deformations. In the case of the backward-swept propeller, the location of the maximum sound pressure level shifts forward by 0.5 °, while in the case of the forward-swept propeller, it shifts backward by 0.5 °. Therefore, aeroacoustic optimization requires the consideration of propeller deformation. Y1 - 2023 U6 - https://doi.org/10.2514/6.2023-0210 N1 - Session: Propeller, Open Rotor, and Rotorcraft Noise II AIAA SCITECH 2023 Forum, 23-27 January 2023, National Harbor, MD & Online PB - AIAA CY - Reston, Va. ER - TY - JOUR A1 - Herzwurm, Georg A1 - Krams, Benedikt A1 - Pietsch, Wolfram A1 - Schockert, Sixten T1 - Report from the 3rd international workshop on requirements prioritization for customer oriented software development (RePriCo’12) JF - ACM SIGSOFT Software Engineering Notes N2 - Prioritization is an essential task within requirements engineering to cope with complexity and to establish focus properly. The 3rd Workshop on Requirements Prioritization for customer oriented Software Development (RePriCo’12) focused on requirements prioritization and adjacent themes in the context of customer oriented development of bespoke and standard software. Five submissions have been accepted for the proceedings and for presentation. The report summarizes and points out key findings. KW - Requirements relations KW - Discourse ethics KW - Tool support KW - Consensus KW - Requirements prioritization Y1 - 2012 U6 - https://doi.org/10.1145/2237796.2237817 SN - 0163-5948 VL - 37 IS - 4 SP - 32 EP - 34 PB - Association for Computing Machinery CY - New York ER - TY - JOUR A1 - Pfaff, Raphael T1 - Braking distance prediction for vehicle consist in low-speed on-sight operation: a Monte Carlo approach JF - Railway Engineering Science N2 - The first and last mile of a railway journey, in both freight and transit applications, constitutes a high effort and is either non-productive (e.g. in the case of depot operations) or highly inefficient (e.g. in industrial railways). These parts are typically managed on-sight, i.e. with no signalling and train protection systems ensuring the freedom of movement. This is possible due to the rather short braking distances of individual vehicles and shunting consists. The present article analyses the braking behaviour of such shunting units. For this purpose, a dedicated model is developed. It is calibrated on published results of brake tests and validated against a high-definition model for low-speed applications. Based on this model, multiple simulations are executed to obtain a Monte Carlo simulation of the resulting braking distances. Based on the distribution properties and established safety levels, the risk of exceeding certain braking distances is evaluated and maximum braking distances are derived. Together with certain parameters of the system, these can serve in the design and safety assessment of driver assistance systems and automation of these processes. KW - Freight rail KW - Shunting KW - Braking curves KW - Brake set-up KW - Driver assistance system Y1 - 2023 U6 - https://doi.org/10.1007/s40534-023-00303-7 SN - 2662-4753 (eISSN) SN - 2662-4745 (Print) VL - 31 IS - 2 SP - 135 EP - 144 PB - SpringerOpen ER - TY - JOUR A1 - Dellmann, Sophia Florence A1 - Glorius, J. A1 - Litvinov, Yu A. A1 - Reifarth, R. A1 - Al-Khasawneh, Kafa A1 - Aliotta, M. A1 - Bott, L. A1 - Brückner, Benjamin A1 - Bruno, C. G. A1 - Chen, Ruijiu A1 - Davinson, T. A1 - Dickel, T. A1 - Dillmann, Iris A1 - Dmytriev, D. A1 - Erbacher, P. A1 - Freire-Fernández, D. A1 - Forstner, Oliver A1 - Geissel, H. A1 - Göbel, K. A1 - Griffin, Christopher J. A1 - Grisenti, R. A1 - Gumberidze, Alexandre A1 - Haettner, Emma A1 - Hagmann, Siegbert A1 - Heil, M. A1 - Heß, R. A1 - Hillenbrand, P.-M. A1 - Joseph, R. A1 - Jurado, B. A1 - Kozhuharov, Christophor A1 - Kulikov, I. A1 - Löher, Bastian A1 - Langer, Christoph A1 - Leckenby, Guy A1 - Lederer-Woods, C. A1 - Lestinsky, M. A1 - Litvinov, S. A. A1 - Lorenz, B. A. A1 - Lorenz, E. A1 - Marsh, J. A1 - Menz, Esther Babette A1 - Morgenroth, T. A1 - Petridis, N. A1 - Pibernat, Jerome A1 - Popp, U. A1 - Psaltis, Athanasios A1 - Sanjari, Shahab A1 - Scheidenberger, C. A1 - Sguazzin, M. A1 - Sidhu, Ragandeep Singh A1 - Spillmann, Uwe A1 - Steck, M. A1 - Stöhlker, T. A1 - Surzhykov, A. A1 - Swartz, J. A. A1 - Törnqvist, H. A1 - Varga, L. A1 - Vescovi, Diego A1 - Weick, H. A1 - Weigand, M. A1 - Woods, P. A1 - Xing, Y. A1 - Yamaguchi, Taiyo T1 - Proton capture on stored radioactive ¹¹⁸Te ions JF - EPJ Web of Conferences N2 - Experimental determination of the cross sections of proton capture on radioactive nuclei is extremely difficult. Therefore, it is of substantial interest for the understanding of the production of the p-nuclei. For the first time, a direct measurement of proton-capture cross sections on stored, radioactive ions became possible in an energy range of interest for nuclear astrophysics. The experiment was performed at the Experimental Storage Ring (ESR) at GSI by making use of a sensitive method to measure (p,γ) and (p,n) reactions in inverse kinematics. These reaction channels are of high relevance for the nucleosyn-thesis processes in supernovae, which are among the most violent explosions in the universe and are not yet well understood. The cross section of the ¹¹⁸Te(p,γ) reaction has been measured at energies of 6 MeV/u and 7 MeV/u. The heavy ions interacted with a hydrogen gas jet target. The radiative recombination process of the fully stripped ¹¹⁸Te ions and electrons from the hydrogen target was used as a luminosity monitor. An overview of the experimental method and preliminary results from the ongoing analysis will be presented. Y1 - 2023 U6 - https://doi.org/10.1051/epjconf/202327911018 SN - 2100-014X N1 - Volume 279, 2023. Nuclear Physics in Astrophysics – X (NPA-X 2022). VL - 279 IS - Article Number: 11018 SP - 1 EP - 5 PB - EDP Sciences ER - TY - JOUR A1 - Bertz, Morten A1 - Molinnus, Denise A1 - Schöning, Michael Josef A1 - Homma, Takayuki T1 - Real-time monitoring of H₂O₂ sterilization on individual bacillus atrophaeus spores by optical sensing with trapping Raman spectroscopy JF - Chemosensors N2 - Hydrogen peroxide (H₂O₂), a strong oxidizer, is a commonly used sterilization agent employed during aseptic food processing and medical applications. To assess the sterilization efficiency with H₂O₂, bacterial spores are common microbial systems due to their remarkable robustness against a wide variety of decontamination strategies. Despite their widespread use, there is, however, only little information about the detailed time-resolved mechanism underlying the oxidative spore death by H₂O₂. In this work, we investigate chemical and morphological changes of individual Bacillus atrophaeus spores undergoing oxidative damage using optical sensing with trapping Raman microscopy in real-time. The time-resolved experiments reveal that spore death involves two distinct phases: (i) an initial phase dominated by the fast release of dipicolinic acid (DPA), a major spore biomarker, which indicates the rupture of the spore’s core; and (ii) the oxidation of the remaining spore material resulting in the subsequent fragmentation of the spores’ coat. Simultaneous observation of the spore morphology by optical microscopy corroborates these mechanisms. The dependence of the onset of DPA release and the time constant of spore fragmentation on H₂O₂ shows that the formation of reactive oxygen species from H₂O₂ is the rate-limiting factor of oxidative spore death. KW - DPA (dipicolinic acid) KW - sterilization KW - Bacillus atrophaeus spores KW - optical trapping KW - Raman spectroscopy KW - optical sensor setup Y1 - 2023 U6 - https://doi.org/10.3390/chemosensors11080445 SN - 2227-9040 N1 - This article belongs to the Special Issue "Biosensors and Chemical Sensors for Food and Healthcare Monitoring—Celebrating the 10th Anniversary" VL - 8 IS - 11 PB - MDPI CY - Basel ER -