@article{StiemerThomaBraun2023, author = {Stiemer, Luc Nicolas and Thoma, Andreas and Braun, Carsten}, title = {MBT3D: Deep learning based multi-object tracker for bumblebee 3D flight path estimation}, series = {PLoS ONE}, volume = {18}, journal = {PLoS ONE}, number = {9}, publisher = {PLOS}, address = {San Fancisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0291415}, pages = {e0291415}, year = {2023}, abstract = {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.}, language = {en} } @article{BergmannGoettenBraunetal.2022, author = {Bergmann, Ole and G{\"o}tten, Falk and Braun, Carsten and Janser, Frank}, title = {Comparison and evaluation of blade element methods against RANS simulations and test data}, series = {CEAS Aeronautical Journal}, volume = {13}, journal = {CEAS Aeronautical Journal}, publisher = {Springer}, address = {Wien}, issn = {1869-5590 (Online)}, doi = {10.1007/s13272-022-00579-1}, pages = {535 -- 557}, year = {2022}, abstract = {This paper compares several blade element theory (BET) method-based propeller simulation tools, including an evaluation against static propeller ground tests and high-fidelity Reynolds-Average Navier Stokes (RANS) simulations. Two proprietary propeller geometries for paraglider applications are analysed in static and flight conditions. The RANS simulations are validated with the static test data and used as a reference for comparing the BET in flight conditions. The comparison includes the analysis of varying 2D aerodynamic airfoil parameters and different induced velocity calculation methods. The evaluation of the BET propeller simulation tools shows the strength of the BET tools compared to RANS simulations. The RANS simulations underpredict static experimental data within 10\% relative error, while appropriate BET tools overpredict the RANS results by 15-20\% relative error. A variation in 2D aerodynamic data depicts the need for highly accurate 2D data for accurate BET results. The nonlinear BET coupled with XFOIL for the 2D aerodynamic data matches best with RANS in static operation and flight conditions. The novel BET tool PropCODE combines both approaches and offers further correction models for highly accurate static and flight condition results.}, language = {en} } @article{MoehrenBergmannJanseretal.2023, author = {M{\"o}hren, Felix and Bergmann, Ole and Janser, Frank and Braun, Carsten}, title = {On the influence of elasticity on propeller performance: a parametric study}, series = {CEAS Aeronautical Journal}, volume = {14}, journal = {CEAS Aeronautical Journal}, publisher = {Springer Nature}, address = {Berlin}, issn = {1869-5590 (Online)}, doi = {10.1007/s13272-023-00649-y}, pages = {311 -- 323}, year = {2023}, abstract = {The aerodynamic performance of propellers strongly depends on their geometry and, consequently, on aeroelastic deformations. Knowledge of the extent of the impact is crucial for overall aircraft performance. An integrated simulation environment for steady aeroelastic propeller simulations is presented. The simulation environment is applied to determine the impact of elastic deformations on the aerodynamic propeller performance. The aerodynamic module includes a blade element momentum approach to calculate aerodynamic loads. The structural module is based on finite beam elements, according to Timoshenko theory, including moderate deflections. Several fixed-pitch propellers with thin-walled cross sections made of both isotropic and non-isotropic materials are investigated. The essential parameters are varied: diameter, disc loading, sweep, material, rotational, and flight velocity. The relative change of thrust between rigid and elastic blades quantifies the impact of propeller elasticity. Swept propellers of large diameters or low disc loadings can decrease the thrust significantly. High flight velocities and low material stiffness amplify this tendency. Performance calculations without consideration of propeller elasticity can lead to decreased efficiency. To avoid cost- and time-intense redesigns, propeller elasticity should be considered for swept planforms and low disc loadings.}, language = {en} } @article{BergmannMoehrenBraunetal.2023, author = {Bergmann, Ole and M{\"o}hren, Felix and Braun, Carsten and Janser, Frank}, title = {On the influence of elasticity on swept propeller noise}, series = {AIAA SCITECH 2023 Forum}, journal = {AIAA SCITECH 2023 Forum}, publisher = {AIAA}, address = {Reston, Va.}, doi = {10.2514/6.2023-0210}, year = {2023}, abstract = {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.}, 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{WilsonBlomeLaFave1996, author = {Wilson, Thomas L. and Blome, Hans-Joachim and LaFave, Norman}, title = {Astrophysical Cosmology Using a Lunar Ligo}, series = {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}, journal = {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}, publisher = {The Society}, address = {New York}, isbn = {0-7844-0177-2}, pages = {861 -- 863}, year = {1996}, language = {en} } @article{SaretzkiBergmannDahmannetal.2021, author = {Saretzki, Charlotte and Bergmann, Ole and Dahmann, Peter and Janser, Frank and Keimer, Jona and Machado, Patricia and Morrison, Audry and Page, Henry and Pluta, Emil and St{\"u}bing, Felix and K{\"u}pper, Thomas}, title = {Are small airplanes safe with regards to COVID-19 transmission?}, series = {Journal of Travel Medicine}, volume = {28}, journal = {Journal of Travel Medicine}, number = {7}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1708-8305}, doi = {10.1093/jtm/taab105}, year = {2021}, language = {en} } @article{BlomeMashhoon1984, author = {Blome, Hans-Joachim and Mashhoon, Bahram}, title = {Quasi-normal oscillations of a Schwarzschild black hole}, series = {Physics Letters A. 100 (1984), H. 5}, journal = {Physics Letters A. 100 (1984), H. 5}, isbn = {0375-9601}, pages = {231 -- 234}, year = {1984}, language = {en} } @article{WeberArentMuenchetal.2016, author = {Weber, Tobias and Arent, Jan-Christoph and M{\"u}nch, Lukas and Duhovic, Miro and Balvers, Johannes Mattheus}, title = {A fast method for the generation of boundary conditions for thermal autoclave simulation}, series = {Composites Part A}, volume = {88}, journal = {Composites Part A}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1359-835X}, doi = {10.1016/j.compositesa.2016.05.036}, pages = {216 -- 225}, year = {2016}, abstract = {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.}, language = {en} } @article{WeberArentSteffenetal.2017, author = {Weber, Tobias and Arent, Jan-Christoph and Steffen, Lucas and Balvers, Johannes Mattheus and Duhovic, Miro}, title = {Thermal optimization of composite autoclave molds using the shift factor approach for boundary condition estimation}, series = {Journal of Composite Materials}, volume = {51}, journal = {Journal of Composite Materials}, number = {12}, publisher = {Sage}, address = {London}, issn = {1530-793X}, doi = {10.1177/0021998317699868}, pages = {1753 -- 1767}, year = {2017}, language = {en} } @article{Esch2010, author = {Esch, Thomas}, title = {Trends in der Nutzfahrzeugantriebstechnik}, series = {Motortechnische Zeitschrift (MTZ)}, volume = {71}, journal = {Motortechnische Zeitschrift (MTZ)}, number = {10}, publisher = {Springer Nature}, address = {Basel}, issn = {0024-8525}, doi = {10.1007/bf03225608}, pages = {652 -- 658}, year = {2010}, abstract = {Umweltzonen und Fahrverbote, kletternde Dieselpreise und steigende Straßenbenutzungsgeb{\"u}hren setzen dem Transportgewerbe aktuell schwer zu. Nutzfahrzeughersteller und Partner finden auf diese Herausforderungen neue Antworten mit der Erf{\"u}llung der EEV-Grenzwerte (Enhanced Environmentally Friendly Vehicle) als den gegenw{\"a}rtig anspruchsvollsten europ{\"a}ischen Abgasstandard f{\"u}r Lkw und Busse.}, language = {de} } @article{BlomeChiconeHehletal.2010, author = {Blome, Hans-Joachim and Chicone, Carmen and Hehl, Friedrich W. and Mashhoon, Bahram}, title = {Nonlocal modification of Newtonian gravity}, series = {Physical Review D}, volume = {81}, journal = {Physical Review D}, number = {6}, publisher = {American Physical Society}, address = {Melville, NY}, issn = {0556-2821}, doi = {10.1103/PhysRevD.81.065020}, year = {2010}, abstract = {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.}, language = {en} } @article{ScholzLeyDachwaldetal.2010, author = {Scholz, A. and Ley, Wilfried and Dachwald, Bernd and Miau, J. J. and Juang, J. C.}, title = {Flight results of the COMPASS-1 picosatellite mission}, series = {Acta Astronautica}, volume = {76}, journal = {Acta Astronautica}, number = {9-10}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0094-5765}, doi = {10.1016/j.actaastro.2010.06.040}, pages = {1289 -- 1298}, year = {2010}, abstract = {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.}, language = {en} } @article{DachwaldMikuckiTulaczyketal.2014, author = {Dachwald, Bernd and Mikucki, Jill and Tulaczyk, Slawek and Digel, Ilya and Espe, Clemens and Feldmann, Marco and Francke, Gero and Kowalski, Julia and Xu, Changsheng}, title = {IceMole : A maneuverable probe for clean in situ analysis and sampling of subsurface ice and subglacial aquatic ecosystems}, series = {Annals of Glaciology}, volume = {55}, journal = {Annals of Glaciology}, number = {65}, publisher = {Cambridge University Press}, address = {Cambridge}, issn = {1727-5644}, doi = {10.3189/2014AoG65A004}, pages = {14 -- 22}, year = {2014}, abstract = {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.}, language = {en} } @article{MikuckiSchulerDigeletal.2023, author = {Mikucki, Jill Ann and Schuler, C. G. and Digel, Ilya and Kowalski, Julia and Tuttle, M. J. and Chua, Michelle and Davis, R. and Purcell, Alicia and Ghosh, D. and Francke, G. and Feldmann, Marco and Espe, C. and Heinen, Dirk and Dachwald, Bernd and Clemens, Joachim and Lyons, W. B. and Tulaczyk, S.}, title = {Field-Based planetary protection operations for melt probes: validation of clean access into the blood falls, antarctica, englacial ecosystem}, series = {Astrobiology}, volume = {23}, journal = {Astrobiology}, number = {11}, publisher = {Liebert}, address = {New York, NY}, issn = {1557-8070 (online)}, doi = {10.1089/ast.2021.0102}, pages = {1165 -- 1178}, year = {2023}, abstract = {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.}, language = {en} } @article{GermanMikuckiWelchetal.2021, author = {German, Laura and Mikucki, Jill A. and Welch, Susan A. and Welch, Kathleen A. and Lutton, Anthony and Dachwald, Bernd and Kowalski, Julia and Heinen, Dirk and Feldmann, Marco and Francke, Gero and Espe, Clemens and Lyons, W. Berry}, title = {Validation of sampling antarctic subglacial hypersaline waters with an electrothermal ice melting probe (IceMole) for environmental analytical geochemistry}, series = {International Journal of Environmental Analytical Chemistry}, volume = {101}, journal = {International Journal of Environmental Analytical Chemistry}, number = {15}, publisher = {Taylor \& Francis}, address = {London}, issn = {0306-7319}, doi = {10.1080/03067319.2019.1704750}, pages = {2654 -- 2667}, year = {2021}, abstract = {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.}, language = {en} } @article{EschWoltersSalberetal.2001, author = {Esch, Thomas and Wolters, Peter and Salber, Wolfgang and Geiger, Jos{\´e}}, title = {Variable Ventilsteuerung und Direkteinspritzung - vom Wettbewerb zur Synergie}, series = {Motor und Umwelt 2001, Internal Combustion Engine Versus Fuel Cell - Potential and Limitations as Automotive Power Sources, Verbrennungsmotor versus Brennstoffzelle - Potenziale und Grenzen f{\"u}r den Automobilantrieb, Proc., Graz, AT, 6.-7. Sep, 2001}, journal = {Motor und Umwelt 2001, Internal Combustion Engine Versus Fuel Cell - Potential and Limitations as Automotive Power Sources, Verbrennungsmotor versus Brennstoffzelle - Potenziale und Grenzen f{\"u}r den Automobilantrieb, Proc., Graz, AT, 6.-7. Sep, 2001}, pages = {183 -- 206}, year = {2001}, language = {de} } @article{SpietzSproewitzSeefeldtetal.2021, author = {Spietz, Peter and Spr{\"o}witz, Tom and Seefeldt, Patric and Grundmann, Jan Thimo and Jahnke, Rico and Mikschl, Tobias and Mikulz, Eugen and Montenegro, Sergio and Reershemius, Siebo and Renger, Thomas and Ruffer, Michael and Sasaki, Kaname and Sznajder, Maciej and T{\´o}th, Norbert and Ceriotti, Matteo and Dachwald, Bernd and Macdonald, Malcolm and McInnes, Colin and Seboldt, Wolfgang and Quantius, Dominik and Bauer, Waldemar and Wiedemann, Carsten and Grimm, Christian D. and Hercik, David and Ho, Tra-Mi and Lange, Caroline and Schmitz, Nicole}, title = {Paths not taken - The Gossamer roadmap's other options}, series = {Advances in Space Research}, volume = {67}, journal = {Advances in Space Research}, number = {9}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0273-1177}, doi = {10.1016/j.asr.2021.01.044}, pages = {2912 -- 2956}, year = {2021}, language = {en} } @article{SchmitzPischinger1997, author = {Schmitz, G{\"u}nter and Pischinger, Martin}, title = {Mechatronische Simulation eines EMV- Aktuators}, series = {TransMechatronik : Entwicklung und Transfer von Entwicklungssystemen der Mechatronik / Paderborner Workshop TransMechatronik, 24. Juni 1997, Heinz-Nixdorf-MuseumsForum. [Hrsg. J{\"u}rgen Gausemeier]}, journal = {TransMechatronik : Entwicklung und Transfer von Entwicklungssystemen der Mechatronik / Paderborner Workshop TransMechatronik, 24. Juni 1997, Heinz-Nixdorf-MuseumsForum. [Hrsg. J{\"u}rgen Gausemeier]}, publisher = {Heinz-Nixdorf-Inst., Univ.-GH Paderborn}, address = {Paderborn}, isbn = {3-931466-22-1}, pages = {69 -- 83}, year = {1997}, language = {de} } @article{EschGoebelPischinger1995, author = {Esch, Thomas and G{\"o}bel, T. and Pischinger, Martin}, title = {Variable Ventilsteuerung - Luft- und Kraftstoffzumessung bei Ottomotoren mit variabler Ventilsteuerung}, series = {Forschungsberichte Verbrennungskraftmaschinen. 578 (1995)}, journal = {Forschungsberichte Verbrennungskraftmaschinen. 578 (1995)}, pages = {1 -- 42}, year = {1995}, language = {de} } @article{SchmitzRoetertPischinger1988, author = {Schmitz, G{\"u}nter and Roetert, J. and Pischinger, Martin}, title = {A Fast Intelligent VMEbus System for Combustion Analysis in Engines}, series = {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.}, journal = {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.}, publisher = {Automotive Automation Ltd}, address = {Croydon}, isbn = {0947719229}, pages = {381 -- 391}, year = {1988}, language = {en} } @article{GrundmannDachwaldGrimmetal.2015, author = {Grundmann, Jan Thimo and Dachwald, Bernd and Grimm, Christian D. and Kahle, Ralph and Koch, Aaron Dexter and Krause, Christian and Lange, Caroline and Quantius, Dominik and Ulamec, Stephan}, title = {Spacecraft for Hypervelocity Impact Research - An Overview of Capabilities, Constraints and the Challenges of Getting There}, series = {Procedia Engineering}, volume = {Vol. 103}, journal = {Procedia Engineering}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1877-7058}, doi = {10.1016/j.proeng.2015.04.021}, pages = {151 -- 158}, year = {2015}, language = {en} } @article{EschSalberKemperetal.2001, author = {Esch, Thomas and Salber, Wolfgang and Kemper, Hans and Staay, F. van der}, title = {Der elektromechanische Ventiltrieb - Systembaustein f{\"u}r zuk{\"u}nftige Antriebskonzepte, Teil 2.}, series = {Motortechnische Zeitschrift (MTZ).}, volume = {62}, journal = {Motortechnische Zeitschrift (MTZ).}, number = {1}, publisher = {Springer Nature}, address = {Basel}, issn = {0024-8525}, doi = {10.1007/bf03227081}, pages = {44 -- 55}, year = {2001}, language = {de} } @article{EschSalberWoltersetal.2002, author = {Esch, Thomas and Salber, Wolfgang and Wolters, Peter and Geiger, Jos{\´e} and Dilthey, Jochen}, title = {Synergies of variable valve actuation and direct injection}, series = {Direct injection SI engine technology 2002 : [SAE 2002 world congress, Detroit, Michigan, USA, March 4 - 7, 2002].}, journal = {Direct injection SI engine technology 2002 : [SAE 2002 world congress, Detroit, Michigan, USA, March 4 - 7, 2002].}, publisher = {Society of Automotive Engineers}, address = {Warrendale, Pa}, isbn = {0-7680-0961-8}, pages = {45 -- 53}, year = {2002}, language = {en} } @article{KowalskiLinderZierkeetal.2016, author = {Kowalski, Julia and Linder, Peter and Zierke, Simon and von Wulfen, Benedikt and Clemens, Joachim and Konstantinidis, Konstantinos and Ameres, Gerald and Hoffmann, Ruth and Mikucki, Jill A. and Tulaczyk, Slawek M. and Funke, Oliver and Blandfort, Daniel and Espe, Clemens and Feldmann, Marco and Francke, Gero and Hiecker, S. and Plescher, Engelbert and Sch{\"o}ngarth, Sarah and Dachwald, Bernd and Digel, Ilya and Artmann, Gerhard and Eliseev, Dmitry and Heinen, Dirk and Scholz, Franziska and Wiebusch, Christopher H. and Macht, Sabine and Bestmann, Ulf and Reineking, Thomas and Zetzsche, Christoph and Schill, Kerstin and F{\"o}rstner, Roger and Niedermeier, Herbert and Szumski, Arkadiusz and Eissfeller, Bernd and Naumann, Uwe and Helbing, Klaus}, title = {Navigation technology for exploration of glacier ice with maneuverable melting probes}, series = {Cold Regions Science and Technology}, journal = {Cold Regions Science and Technology}, number = {123}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0165-232X}, doi = {10.1016/j.coldregions.2015.11.006}, pages = {53 -- 70}, year = {2016}, abstract = {The Saturnian moon Enceladus with its extensive water bodies underneath a thick ice sheet cover is a potential candidate for extraterrestrial life. Direct exploration of such extraterrestrial aquatic ecosystems requires advanced access and sampling technologies with a high level of autonomy. A new technological approach has been developed as part of the collaborative research project Enceladus Explorer (EnEx). The concept is based upon a minimally invasive melting probe called the IceMole. The force-regulated, heater-controlled IceMole is able to travel along a curved trajectory as well as upwards. Hence, it allows maneuvers which may be necessary for obstacle avoidance or target selection. Maneuverability, however, necessitates a sophisticated on-board navigation system capable of autonomous operations. The development of such a navigational system has been the focal part of the EnEx project. The original IceMole has been further developed to include relative positioning based on in-ice attitude determination, acoustic positioning, ultrasonic obstacle and target detection integrated through a high-level sensor fusion. This paper describes the EnEx technology and discusses implications for an actual extraterrestrial mission concept.}, language = {en} } @article{WittmannBibringRosenbaueretal.2007, author = {Wittmann, Klaus and Bibring, J.-P. and Rosenbauer, H. and Boehnhardt, H. and Ulamec, S. and Biele, Jens and Espinasse, S. and Feuerbacher, B. and Gaudon, Philippe and Hemmerich, P. and Kletzkine, P. and Moura, Dioc and Mugnuolo, R. and Nietner, G. and P{\"a}tz, B. and Roll, R. and Scheuerle, H. and Szeg{\"o}, Karoly}, title = {The Rosetta Lander ("Philae") Investigations / Bibring, J.-P. ; Rosenbauer, H. ; Boehnhardt, H. ; [...] Wittmann, K.}, series = {Space Science Reviews. 128 (2007), H. 1-4}, journal = {Space Science Reviews. 128 (2007), H. 1-4}, isbn = {0038-6308}, pages = {205 -- 220}, year = {2007}, language = {en} } @article{GoettenFingerHavermannetal.2021, author = {G{\"o}tten, Falk and Finger, Felix and Havermann, Marc and Braun, Carsten and Marino, Matthew and Bil, Cees}, title = {Full configuration drag estimation of short-to-medium range fixed-wing UAVs and its impact on initial sizing optimization}, series = {CEAS Aeronautical Journal}, volume = {12}, journal = {CEAS Aeronautical Journal}, publisher = {Springer}, address = {Berlin}, issn = {1869-5590 (Online)}, doi = {10.1007/s13272-021-00522-w}, pages = {589 -- 603}, year = {2021}, abstract = {The paper presents the derivation of a new equivalent skin friction coefficient for estimating the parasitic drag of short-to-medium range fixed-wing unmanned aircraft. The new coefficient is derived from an aerodynamic analysis of ten different unmanned aircraft used for surveillance, reconnaissance, and search and rescue missions. The aircraft is simulated using a validated unsteady Reynolds-averaged Navier Stokes approach. The UAV's parasitic drag is significantly influenced by the presence of miscellaneous components like fixed landing gears or electro-optical sensor turrets. These components are responsible for almost half of an unmanned aircraft's total parasitic drag. The new equivalent skin friction coefficient accounts for these effects and is significantly higher compared to other aircraft categories. It is used to initially size an unmanned aircraft for a typical reconnaissance mission. The improved parasitic drag estimation yields a much heavier unmanned aircraft when compared to the sizing results using available drag data of manned aircraft.}, language = {en} } @article{GrundmannBauerBieleetal.2019, author = {Grundmann, Jan Thimo and Bauer, Waldemar and Biele, Jens and Boden, Ralf Christian and Ceriotti, Matteo and Cordero, Federico and Dachwald, Bernd and Dumont, Etienne and Grimm, Christian D. and Hercik, David}, title = {Capabilities of Gossamer-1 derived small spacecraft solar sails carrying Mascot-derived nanolanders for in-situ surveying of NEAs}, series = {Acta Astronautica}, volume = {156}, journal = {Acta Astronautica}, number = {3}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0094-5765}, doi = {10.1016/j.actaastro.2018.03.019}, pages = {330 -- 362}, year = {2019}, language = {en} } @article{BohnFunkeGier1999, author = {Bohn, Dieter and Funke, Harald and Gier, Jochen}, title = {Temperature jet development in a cross-over channel}, series = {Third European Conference on Turbomachinery - fluid dynamics and thermodynamics : : 2 - 5 March 1999, Royal National Hotel, London, UK / organized by the Energy Transfer and Thermofluid Mechanics Group of the Institution of Mechanical Engineers (IMechE); with support and sponsorship from European Commission / Vol. B.}, journal = {Third European Conference on Turbomachinery - fluid dynamics and thermodynamics : : 2 - 5 March 1999, Royal National Hotel, London, UK / organized by the Energy Transfer and Thermofluid Mechanics Group of the Institution of Mechanical Engineers (IMechE); with support and sponsorship from European Commission / Vol. B.}, publisher = {Professional Engineering Publ.}, address = {Bury St. Edmunds}, pages = {671 -- 680}, year = {1999}, language = {en} } @article{HajAyedKustererFunkeetal.2017, author = {Haj-Ayed, Anis and Kusterer, Karsten and Funke, Harald and Keinz, Jan and Bohn, Dieter E.}, title = {CFD based exploration of the dry-low-NOx hydrogen micromix combustion technology at increased energy densities}, series = {Propulsion and Power Research}, volume = {6}, journal = {Propulsion and Power Research}, number = {1}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {2212-540X}, doi = {10.1016/j.jppr.2017.01.005}, pages = {15 -- 24}, year = {2017}, language = {en} } @article{HajAyedKustererFunkeetal.2015, author = {Haj-Ayed, Anis and Kusterer, Karsten A. and Funke, Harald and Keinz, Jan and Striegan, Constantin and Bohn, Dieter E.}, title = {Experimental and numerical investigations of the dry-low-NOx hydrogen micromix combustion chamber of an industrial gas turbine}, series = {Propulsion and power research}, volume = {Vol. 4}, journal = {Propulsion and power research}, number = {Iss. 3}, issn = {2212-540X}, doi = {10.1016/j.jppr.2015.07.005}, pages = {123 -- 131}, year = {2015}, language = {en} } @article{HajAyedKustererFunkeetal.2015, author = {Haj-Ayed, Anis and Kusterer, Karsten, A. and Funke, Harald and Keinz, Jan and Striegan, Constantin and Bohn, Dieter E.}, title = {Improvement study for the dry-low-NOx hydrogen micromix combustion technology}, series = {Propulsion and power research}, volume = {Vol. 4}, journal = {Propulsion and power research}, number = {Iss. 3}, issn = {2212-540X}, doi = {10.1016/j.jppr.2015.07.003}, pages = {132 -- 140}, year = {2015}, language = {en} } @article{BohnFunkeHeueretal.2000, author = {Bohn, Dieter E. and Funke, Harald and Heuer, Tom and B{\"u}tikofer, J.}, title = {Numerical and experimental investigations of the influence of different swirl-ratios on the temperature streak equalization in a 4-stage turbine}, series = {ASME Turbo Expo 2000 ; Munich, May 8-11 2000}, journal = {ASME Turbo Expo 2000 ; Munich, May 8-11 2000}, address = {Munich}, year = {2000}, language = {en} } @article{BohnFunke2003, author = {Bohn, Dieter E. and Funke, Harald}, title = {Experimental investigations into the nonuniform flow in a 4-stage turbine with special focus on the flow equalization in the first turbine stage}, series = {ASME TURBO EXPO, Proceedings of the ASME Turbo Expo, 2003}, journal = {ASME TURBO EXPO, Proceedings of the ASME Turbo Expo, 2003}, isbn = {0-7918-3689-4}, pages = {281 -- 289}, year = {2003}, language = {en} } @article{BohnFunkeGier1999, author = {Bohn, Dieter and Funke, Harald and Gier, Jochen}, title = {Numerical and Experimental Investigations on the Flow in a 4-Stage Turbine with Special Focus on the Development of a Radial Temperature Streak}, series = {ASME Turbo Expo 1999, Indianapolis, USA, 1999}, journal = {ASME Turbo Expo 1999, Indianapolis, USA, 1999}, year = {1999}, language = {en} }