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 - Esch, Thomas T1 - Trends in commercial vehicle powertrains JF - ATZautotechnology N2 - Low emission zones and truck bans, the rising price of diesel and increases in road tolls: all of these factors are putting serious pressure on the transport industry. Commercial vehicle manufacturers and their suppliers are in the process of identifying new solutions to these challenges as part of their efforts to meet the EEV (enhanced environmentally friendly vehicle) limits, which are currently the most robust European exhaust and emissions standards for trucks and buses. KW - European Transient Cycle KW - Common Rail Injection System KW - Commercial Vehicle KW - Selective Catalytic Reduction KW - Diesel Engine Y1 - 2010 U6 - https://doi.org/10.1007/BF03247185 SN - 2192-886X VL - 2010 IS - 10 SP - 26 EP - 31 PB - Vieweg & Sohn CY - Wiesbaden ER - TY - JOUR A1 - Stiemer, Luc Nicolas A1 - Thoma, Andreas A1 - Braun, Carsten T1 - MBT3D: Deep learning based multi-object tracker for bumblebee 3D flight path estimation JF - PLoS ONE N2 - This work presents the Multi-Bees-Tracker (MBT3D) algorithm, a Python framework implementing a deep association tracker for Tracking-By-Detection, to address the challenging task of tracking flight paths of bumblebees in a social group. While tracking algorithms for bumblebees exist, they often come with intensive restrictions, such as the need for sufficient lighting, high contrast between the animal and background, absence of occlusion, significant user input, etc. Tracking flight paths of bumblebees in a social group is challenging. They suddenly adjust movements and change their appearance during different wing beat states while exhibiting significant similarities in their individual appearance. The MBT3D tracker, developed in this research, is an adaptation of an existing ant tracking algorithm for bumblebee tracking. It incorporates an offline trained appearance descriptor along with a Kalman Filter for appearance and motion matching. Different detector architectures for upstream detections (You Only Look Once (YOLOv5), Faster Region Proposal Convolutional Neural Network (Faster R-CNN), and RetinaNet) are investigated in a comparative study to optimize performance. The detection models were trained on a dataset containing 11359 labeled bumblebee images. YOLOv5 reaches an Average Precision of AP = 53, 8%, Faster R-CNN achieves AP = 45, 3% and RetinaNet AP = 38, 4% on the bumblebee validation dataset, which consists of 1323 labeled bumblebee images. The tracker’s appearance model is trained on 144 samples. The tracker (with Faster R-CNN detections) reaches a Multiple Object Tracking Accuracy MOTA = 93, 5% and a Multiple Object Tracking Precision MOTP = 75, 6% on a validation dataset containing 2000 images, competing with state-of-the-art computer vision methods. The framework allows reliable tracking of different bumblebees in the same video stream with rarely occurring identity switches (IDS). MBT3D has much lower IDS than other commonly used algorithms, with one of the lowest false positive rates, competing with state-of-the-art animal tracking algorithms. The developed framework reconstructs the 3-dimensional (3D) flight paths of the bumblebees by triangulation. It also handles and compares two alternative stereo camera pairs if desired. Y1 - 2023 U6 - https://doi.org/10.1371/journal.pone.0291415 SN - 1932-6203 N1 - Corresponding author: Luc Nicolas Stiemer VL - 18 IS - 9 PB - PLOS CY - San Fancisco 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 - Wilson, Thomas L. A1 - Blome, Hans-Joachim A1 - LaFave, Norman T1 - Astrophysical Cosmology Using a Lunar Ligo JF - Engineering, construction, and operations in space V : proceedings of the Fifth International Conference on Space '96, Albuquerque, New Mexico, June 1-6, 1996 / sponsored by Aerospace Division of the American Society of Civil Engineers ... [et al.]; edite Y1 - 1996 SN - 0-7844-0177-2 SP - 861 EP - 863 PB - The Society CY - New York ER - TY - JOUR A1 - Saretzki, Charlotte A1 - Bergmann, Ole A1 - Dahmann, Peter A1 - Janser, Frank A1 - Keimer, Jona A1 - Machado, Patricia A1 - Morrison, Audry A1 - Page, Henry A1 - Pluta, Emil A1 - Stübing, Felix A1 - Küpper, Thomas T1 - Are small airplanes safe with regards to COVID-19 transmission? JF - Journal of Travel Medicine Y1 - 2021 U6 - https://doi.org/10.1093/jtm/taab105 SN - 1708-8305 VL - 28 IS - 7 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Blome, Hans-Joachim A1 - Mashhoon, Bahram T1 - Quasi-normal oscillations of a Schwarzschild black hole JF - Physics Letters A. 100 (1984), H. 5 Y1 - 1984 SN - 0375-9601 SP - 231 EP - 234 ER - TY - JOUR A1 - Weber, Tobias A1 - Arent, Jan-Christoph A1 - Münch, Lukas A1 - Duhovic, Miro A1 - Balvers, Johannes Mattheus T1 - A fast method for the generation of boundary conditions for thermal autoclave simulation JF - Composites Part A N2 - Manufacturing process simulation enables the evaluation and improvement of autoclave mold concepts early in the design phase. To achieve a high part quality at low cycle times, the thermal behavior of the autoclave mold can be investigated by means of simulations. Most challenging for such a simulation is the generation of necessary boundary conditions. Heat-up and temperature distribution in an autoclave mold are governed by flow phenomena, tooling material and shape, position within the autoclave, and the chosen autoclave cycle. This paper identifies and summarizes the most important factors influencing mold heat-up and how they can be introduced into a thermal simulation. Thermal measurements are used to quantify the impact of the various parameters. Finally, the gained knowledge is applied to develop a semi-empirical approach for boundary condition estimation that enables a simple and fast thermal simulation of the autoclave curing process with reasonably high accuracy for tooling optimization. Y1 - 2016 U6 - https://doi.org/10.1016/j.compositesa.2016.05.036 SN - 1359-835X VL - 88 SP - 216 EP - 225 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Weber, Tobias A1 - Arent, Jan-Christoph A1 - Steffen, Lucas A1 - Balvers, Johannes Mattheus A1 - Duhovic, Miro T1 - Thermal optimization of composite autoclave molds using the shift factor approach for boundary condition estimation JF - Journal of Composite Materials Y1 - 2017 U6 - https://doi.org/10.1177/0021998317699868 SN - 1530-793X VL - 51 IS - 12 SP - 1753 EP - 1767 PB - Sage CY - London ER - TY - JOUR A1 - Esch, Thomas T1 - Trends in der Nutzfahrzeugantriebstechnik JF - Motortechnische Zeitschrift (MTZ) N2 - Umweltzonen und Fahrverbote, kletternde Dieselpreise und steigende Straßenbenutzungsgebühren setzen dem Transportgewerbe aktuell schwer zu. Nutzfahrzeughersteller und Partner finden auf diese Herausforderungen neue Antworten mit der Erfüllung der EEV-Grenzwerte (Enhanced Environmentally Friendly Vehicle) als den gegenwärtig anspruchsvollsten europäischen Abgasstandard für Lkw und Busse. Y1 - 2010 U6 - https://doi.org/10.1007/bf03225608 SN - 0024-8525 VL - 71 IS - 10 SP - 652 EP - 658 PB - Springer Nature CY - Basel ER - TY - JOUR A1 - Blome, Hans-Joachim A1 - Chicone, Carmen A1 - Hehl, Friedrich W. A1 - Mashhoon, Bahram T1 - Nonlocal modification of Newtonian gravity JF - Physical Review D N2 - The Newtonian regime of a recent nonlocal extension of general relativity is investigated. Nonlocality is introduced via a scalar “constitutive” kernel in a special case of the translational gauge theory of gravitation, namely, the teleparallel equivalent of general relativity. In this theory, the nonlocal aspect of gravity simulates dark matter. A nonlocal and nonlinear generalization of Poisson’s equation of Newtonian gravitation is presented. The implications of nonlocality for the gravitational physics in the solar system are briefly studied. Y1 - 2010 U6 - https://doi.org/10.1103/PhysRevD.81.065020 SN - 0556-2821 VL - 81 IS - 6 EP - 065020 PB - American Physical Society CY - Melville, NY ER - TY - JOUR A1 - Scholz, A. A1 - Ley, Wilfried A1 - Dachwald, Bernd A1 - Miau, J. J. A1 - Juang, J. C. T1 - Flight results of the COMPASS-1 picosatellite mission JF - Acta Astronautica N2 - The mission of the COMPASS-1 picosatellite is to take pictures of the earth, to validate a space-borne GPS receiver developed by the German Aerospace Center, and to verify the proper operation of the magnetic attitude control system in orbit. The spacecraft was launched on April 28, 2008 from the Indian space port Sriharikota, as part of the PSLV-C9 world record launch that simultaneously brought ten satellites into orbit. The mission operations were carried out from the ground stations in Aachen and Tainan. Arising difficulties in the communication link were overcome with the support of individuals from the amateur radio community. After several months of mission operation, abundant housekeeping and mission data has been commanded, received and analyzed and is presented in this paper. Y1 - 2010 U6 - https://doi.org/10.1016/j.actaastro.2010.06.040 SN - 0094-5765 VL - 76 IS - 9-10 SP - 1289 EP - 1298 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Dachwald, Bernd A1 - Mikucki, Jill A1 - Tulaczyk, Slawek A1 - Digel, Ilya A1 - Espe, Clemens A1 - Feldmann, Marco A1 - Francke, Gero A1 - Kowalski, Julia A1 - Xu, Changsheng T1 - IceMole : A maneuverable probe for clean in situ analysis and sampling of subsurface ice and subglacial aquatic ecosystems JF - Annals of Glaciology N2 - There is significant interest in sampling subglacial environments for geobiological studies, but they are difficult to access. Existing ice-drilling technologies make it cumbersome to maintain microbiologically clean access for sample acquisition and environmental stewardship of potentially fragile subglacial aquatic ecosystems. The IceMole is a maneuverable subsurface ice probe for clean in situ analysis and sampling of glacial ice and subglacial materials. The design is based on the novel concept of combining melting and mechanical propulsion. It can change melting direction by differential heating of the melting head and optional side-wall heaters. The first two prototypes were successfully tested between 2010 and 2012 on glaciers in Switzerland and Iceland. They demonstrated downward, horizontal and upward melting, as well as curve driving and dirt layer penetration. A more advanced probe is currently under development as part of the Enceladus Explorer (EnEx) project. It offers systems for obstacle avoidance, target detection, and navigation in ice. For the EnEx-IceMole, we will pay particular attention to clean protocols for the sampling of subglacial materials for biogeochemical analysis. We plan to use this probe for clean access into a unique subglacial aquatic environment at Blood Falls, Antarctica, with return of a subglacial brine sample. KW - Antarctic Glaciology KW - Extraterrestrial Glaciology KW - Glaciological instruments and methods KW - Subclacial exploration KW - Subglacial lakes Y1 - 2014 U6 - https://doi.org/10.3189/2014AoG65A004 SN - 1727-5644 VL - 55 IS - 65 SP - 14 EP - 22 PB - Cambridge University Press CY - Cambridge ER - TY - JOUR A1 - Mikucki, Jill Ann A1 - Schuler, C. G. A1 - Digel, Ilya A1 - Kowalski, Julia A1 - Tuttle, M. J. A1 - Chua, Michelle A1 - Davis, R. A1 - Purcell, Alicia A1 - Ghosh, D. A1 - Francke, G. A1 - Feldmann, Marco A1 - Espe, C. A1 - Heinen, Dirk A1 - Dachwald, Bernd A1 - Clemens, Joachim A1 - Lyons, W. B. A1 - Tulaczyk, S. T1 - Field-Based planetary protection operations for melt probes: validation of clean access into the blood falls, antarctica, englacial ecosystem JF - Astrobiology N2 - Subglacial environments on Earth offer important analogs to Ocean World targets in our solar system. These unique microbial ecosystems remain understudied due to the challenges of access through thick glacial ice (tens to hundreds of meters). Additionally, sub-ice collections must be conducted in a clean manner to ensure sample integrity for downstream microbiological and geochemical analyses. We describe the field-based cleaning of a melt probe that was used to collect brine samples from within a glacier conduit at Blood Falls, Antarctica, for geomicrobiological studies. We used a thermoelectric melting probe called the IceMole that was designed to be minimally invasive in that the logistical requirements in support of drilling operations were small and the probe could be cleaned, even in a remote field setting, so as to minimize potential contamination. In our study, the exterior bioburden on the IceMole was reduced to levels measured in most clean rooms, and below that of the ice surrounding our sampling target. Potential microbial contaminants were identified during the cleaning process; however, very few were detected in the final englacial sample collected with the IceMole and were present in extremely low abundances (∼0.063% of 16S rRNA gene amplicon sequences). This cleaning protocol can help minimize contamination when working in remote field locations, support microbiological sampling of terrestrial subglacial environments using melting probes, and help inform planetary protection challenges for Ocean World analog mission concepts. Y1 - 2023 U6 - https://doi.org/10.1089/ast.2021.0102 SN - 1557-8070 (online) SN - 153-1074 (print) VL - 23 IS - 11 SP - 1165 EP - 1178 PB - Liebert CY - New York, NY ER - TY - JOUR A1 - German, Laura A1 - Mikucki, Jill A. A1 - Welch, Susan A. A1 - Welch, Kathleen A. A1 - Lutton, Anthony A1 - Dachwald, Bernd A1 - Kowalski, Julia A1 - Heinen, Dirk A1 - Feldmann, Marco A1 - Francke, Gero A1 - Espe, Clemens A1 - Lyons, W. Berry T1 - Validation of sampling antarctic subglacial hypersaline waters with an electrothermal ice melting probe (IceMole) for environmental analytical geochemistry JF - International Journal of Environmental Analytical Chemistry N2 - Geochemical characterisation of hypersaline waters is difficult as high concentrations of salts hinder the analysis of constituents at low concentrations, such as trace metals, and the collection of samples for trace metal analysis in natural waters can be easily contaminated. This is particularly the case if samples are collected by non-conventional techniques such as those required for aquatic subglacial environments. In this paper we present the first analysis of a subglacial brine from Taylor Valley, (~ 78°S), Antarctica for the trace metals: Ba, Co, Mo, Rb, Sr, V, and U. Samples were collected englacially using an electrothermal melting probe called the IceMole. This probe uses differential heating of a copper head as well as the probe’s sidewalls and an ice screw at the melting head to move through glacier ice. Detailed blanks, meltwater, and subglacial brine samples were collected to evaluate the impact of the IceMole and the borehole pump, the melting and collection process, filtration, and storage on the geochemistry of the samples collected by this device. Comparisons between melt water profiles through the glacier ice and blank analysis, with published studies on ice geochemistry, suggest the potential for minor contributions of some species Rb, As, Co, Mn, Ni, NH4+, and NO2−+NO3− from the IceMole. The ability to conduct detailed chemical analyses of subglacial fluids collected with melting probes is critical for the future exploration of the hundreds of deep subglacial lakes in Antarctica. Y1 - 2021 U6 - https://doi.org/10.1080/03067319.2019.1704750 SN - 0306-7319 VL - 101 IS - 15 SP - 2654 EP - 2667 PB - Taylor & Francis CY - London ER - TY - JOUR A1 - Esch, Thomas A1 - Wolters, Peter A1 - Salber, Wolfgang A1 - Geiger, José T1 - Variable Ventilsteuerung und Direkteinspritzung - vom Wettbewerb zur Synergie JF - Motor und Umwelt 2001, Internal Combustion Engine Versus Fuel Cell - Potential and Limitations as Automotive Power Sources, Verbrennungsmotor versus Brennstoffzelle - Potenziale und Grenzen für den Automobilantrieb, Proc., Graz, AT, 6.-7. Sep, 2001 Y1 - 2001 N1 - Konferenz-Einzelbericht SP - 183 EP - 206 ER - TY - JOUR A1 - Spietz, Peter A1 - Spröwitz, Tom A1 - Seefeldt, Patric A1 - Grundmann, Jan Thimo A1 - Jahnke, Rico A1 - Mikschl, Tobias A1 - Mikulz, Eugen A1 - Montenegro, Sergio A1 - Reershemius, Siebo A1 - Renger, Thomas A1 - Ruffer, Michael A1 - Sasaki, Kaname A1 - Sznajder, Maciej A1 - Tóth, Norbert A1 - Ceriotti, Matteo A1 - Dachwald, Bernd A1 - Macdonald, Malcolm A1 - McInnes, Colin A1 - Seboldt, Wolfgang A1 - Quantius, Dominik A1 - Bauer, Waldemar A1 - Wiedemann, Carsten A1 - Grimm, Christian D. A1 - Hercik, David A1 - Ho, Tra-Mi A1 - Lange, Caroline A1 - Schmitz, Nicole T1 - Paths not taken – The Gossamer roadmap’s other options JF - Advances in Space Research KW - Solar sail KW - Small spacecraft KW - DLR-ESTEC GOSSAMER roadmap for solar sailing KW - GOSSAMER-1 Y1 - 2021 U6 - https://doi.org/10.1016/j.asr.2021.01.044 SN - 0273-1177 VL - 67 IS - 9 SP - 2912 EP - 2956 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Schmitz, Günter A1 - Pischinger, Martin T1 - Mechatronische Simulation eines EMV- Aktuators JF - TransMechatronik : Entwicklung und Transfer von Entwicklungssystemen der Mechatronik / Paderborner Workshop TransMechatronik, 24. Juni 1997, Heinz-Nixdorf-MuseumsForum. [Hrsg. Jürgen Gausemeier] Y1 - 1997 SN - 3-931466-22-1 N1 - HNI-Verlagsschriftenreihe ; 23 SP - 69 EP - 83 PB - Heinz-Nixdorf-Inst., Univ.-GH Paderborn CY - Paderborn ER - TY - JOUR A1 - Esch, Thomas A1 - Göbel, T. A1 - Pischinger, Martin T1 - Variable Ventilsteuerung - Luft- und Kraftstoffzumessung bei Ottomotoren mit variabler Ventilsteuerung JF - Forschungsberichte Verbrennungskraftmaschinen. 578 (1995) Y1 - 1995 N1 - Report SP - 1 EP - 42 ER - TY - JOUR A1 - Schmitz, Günter A1 - Roetert, J. A1 - Pischinger, Martin T1 - A Fast Intelligent VMEbus System for Combustion Analysis in Engines JF - 19th [nineteenth] International Symposium on Automotive Technology & [and] Automation : with particular reference to cell control and quality management systems for the manufacturing industries; Monte Carlo, 24. - 28. October 1988. Y1 - 1988 SN - 0947719229 SP - 381 EP - 391 PB - Automotive Automation Ltd CY - Croydon ER -