@inproceedings{DachwaldMengaliQuartaetal.2007, author = {Dachwald, Bernd and Mengali, Giovanni and Quarta, Alessandro A and Macdonald, Malcolm and McInnes, Colin R}, title = {Optical solar sail degradation modelling}, series = {1st International Symposium on Solar Sailing}, booktitle = {1st International Symposium on Solar Sailing}, pages = {1 -- 27}, year = {2007}, abstract = {We propose a simple parametric OSSD model that describes the variation of the sail film's optical coefficients with time, depending on the sail film's environmental history, i.e., the radiation dose. The primary intention of our model is not to describe the exact behavior of specific film-coating combinations in the real space environment, but to provide a more general parametric framework for describing the general optical degradation behavior of solar sails.}, language = {en} } @article{DachwaldMengaliQuartaetal.2007, author = {Dachwald, Bernd and Mengali, Giovanni and Quarta, Alessandro A. and Circi, Christian}, title = {Refined Solar Sail Force Model with Mission Application / Giovanni Mengali ; Alessandro A. Quarta , Christian Circi ; Bernd Dachwald}, series = {Journal of Guidance, Control, and Dynamics. 30 (2007), H. 2}, journal = {Journal of Guidance, Control, and Dynamics. 30 (2007), H. 2}, isbn = {0162-3192}, pages = {512 -- 520}, year = {2007}, language = {en} } @inproceedings{DachwaldMikuckiTulaczyketal.2012, author = {Dachwald, Bernd and Mikucki, Jill A. and Tulaczyk, Slawek and Digel, Ilya and Feldmann, Marco and Espe, Clemens and Plescher, Engelbert and Xu, Changsheng}, title = {IceMole - a maneuverable probe for clean in-situ analysis and sampling of subsurface ice and subglacial aquatic ecosystems : extended abstract / SCAR Open Science Conference 2012, Session 29: Advancing Clean Technologies for Exploration of Glacial Aquatic Ecosystems}, year = {2012}, abstract = {The "IceMole" is a novel maneuverable subsurface ice probe for clean in-situ analysis and sampling of subsurface ice and subglacial water/brine. It is developed and build at FH Aachen University of Applied Sciences' Astronautical Laboratory. A first prototype was successfully tested on the Swiss Morteratsch glacier in 2010. Clean sampling is achieved with a hollow ice screw (as it is used in mountaineering) at the tip of the probe. Maneuverability is achieved with a differentially heated melting head. Funded by the German Space Agency (DLR), a consortium led by FH Aachen currently develops a much more advanced IceMole probe, which includes a sophisticated system for obstacle avoidance, target detection, and navigation in the ice. We intend to use this probe for taking clean samples of subglacial brine at the Blood Falls (McMurdo Dry Valleys, East Antarctica) for chemical and microbiological analysis. In our conference contribution, we 1) describe the IceMole design, 2) report the results of the field tests of the first prototype on the Morteratsch glacier, 3) discuss the probe's potential for the clean in-situ analysis and sampling of subsurface ice and subglacial liquids, and 4) outline the way ahead in the development of this technology.}, subject = {Eisschicht}, 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{DachwaldOhndorf2007, author = {Dachwald, Bernd and Ohndorf, A.}, title = {1st ACT Global Trajectory Optimisation Competition : Results found at DLR}, series = {Acta Astronautica. 61 (2007), H. 9}, journal = {Acta Astronautica. 61 (2007), H. 9}, isbn = {0094-5765}, pages = {742 -- 752}, year = {2007}, language = {en} } @article{DachwaldOhndorfGill2009, author = {Dachwald, Bernd and Ohndorf, A. and Gill, E.}, title = {Optimization of low-thrust Earth-Moon transfers using evolutionary neurocontrol / Ohndorf, A. ; Dachwald, B. ; Gill, E.}, series = {IEEE Congress on Evolutionary Computation, 2009. CEC '09.}, journal = {IEEE Congress on Evolutionary Computation, 2009. CEC '09.}, isbn = {978-1-4244-2958-5}, pages = {358 -- 364}, year = {2009}, language = {en} } @article{DachwaldOhndorfWie2006, author = {Dachwald, Bernd and Ohndorf, A. and Wie, Bong}, title = {Solar Sail Trajectory Optimization for the Solar Polar Imager (SPI) Mission}, series = {AIAA Guidance, Navigation, and Control Conference \& Exhibit - AIAA Atmospheric Flight Mechanics Conference \& Exhibit - AIAA Modeling and Simulation Technologies Conference \& Exhibit - AIAA/AAS Astrodynamics Specialist Conference \& Exhibit : [21 - 24 August 2006, Keystone, Colorado ; papers]. - (AIAA meeting papers on disc ; [11.]2006,19-20 )}, journal = {AIAA Guidance, Navigation, and Control Conference \& Exhibit - AIAA Atmospheric Flight Mechanics Conference \& Exhibit - AIAA Modeling and Simulation Technologies Conference \& Exhibit - AIAA/AAS Astrodynamics Specialist Conference \& Exhibit : [21 - 24 August 2006, Keystone, Colorado ; papers]. - (AIAA meeting papers on disc ; [11.]2006,19-20 )}, publisher = {American Institute of Aeronautics and Astronautics}, address = {Reston, Va.}, isbn = {1-56347-802-1}, pages = {2 CD-ROMs.}, year = {2006}, language = {en} } @incollection{DachwaldOhndorf2019, author = {Dachwald, Bernd and Ohndorf, Andreas}, title = {Global optimization of continuous-thrust trajectories using evolutionary neurocontrol}, series = {Modeling and Optimization in Space Engineering}, booktitle = {Modeling and Optimization in Space Engineering}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-10501-3}, doi = {10.1007/978-3-030-10501-3_2}, pages = {33 -- 57}, year = {2019}, abstract = {Searching optimal continuous-thrust trajectories is usually a difficult and time-consuming task. The solution quality of traditional optimal-control methods depends strongly on an adequate initial guess because the solution is typically close to the initial guess, which may be far from the (unknown) global optimum. Evolutionary neurocontrol attacks continuous-thrust optimization problems from the perspective of artificial intelligence and machine learning, combining artificial neural networks and evolutionary algorithms. This chapter describes the method and shows some example results for single- and multi-phase continuous-thrust trajectory optimization problems to assess its performance. Evolutionary neurocontrol can explore the trajectory search space more exhaustively than a human expert can do with traditional optimal-control methods. Especially for difficult problems, it usually finds solutions that are closer to the global optimum. Another fundamental advantage is that continuous-thrust trajectories can be optimized without an initial guess and without expert supervision.}, language = {en} } @inproceedings{DachwaldOhndorfSpurmannetal.2009, author = {Dachwald, Bernd and Ohndorf, Andreas and Spurmann, J. and Loeb, H. W. and Schartner, Karl-Heinz and Seboldt, Wolfgang}, title = {Mission design for a SEP mission to saturn}, series = {60th International Astronautical Congress 2009 (IAC 2009)}, booktitle = {60th International Astronautical Congress 2009 (IAC 2009)}, publisher = {Curran Associates, Inc.}, address = {Red Hook, NY}, isbn = {978-1-61567-908-9}, pages = {11 Seiten}, year = {2009}, abstract = {Within ESA's Cosmic Vision 2015-2025 plan, a mission to explore the Saturnian System, with special emphasis on its two moons Titan and Enceladus, was selected for study, termed TANDEM (Titan and Enceladus Mission). In this paper, we describe an optimized mission design for a TANDEM-derived solar electric propulsion (SEP) mission. We have chosen the SEP mission scenario for the interplanetary transfer of the TANDEM spacecraft because all feasible gravity assist sequences for a chemical transfer between 2015 and 2025 result in long flight times of about nine years. Our SEP system is based on the German RIT ion engine. For our optimized mission design, we have extensively explored the SEP parameter space (specific impulse, thrust level, power level) and have calculated an optimal interplanetary trajectory for each setting. In contrast to the original TANDEM mission concept, which intends to use two launch vehicles and an all-chemical transfer, our SEP mission design requires only a single Ariane 5 ECA launch for the same payload mass. Without gravity assist, it yields a faster and more flexible transfer with a fight time of less than seven years, and an increased payload ratio. Our mission design proves thereby the capability of SEP even for missions into the outer solar system.}, language = {en} } @article{DachwaldSchmidtSeboldtetal.2003, author = {Dachwald, Bernd and Schmidt, Tanja D. and Seboldt, Wolfgang and Auweter-Kurtz,}, title = {Flight Opportunities from Mars to Earth for Piloted Missions Using Continuous Thrust Propulsion / Schmidt, Tanja D. ; Dachwald, Bernd ; Seboldt, Wolfgang ; Auweter-Kurtz, Monika}, publisher = {-}, pages = {1 -- 9}, year = {2003}, language = {en} } @article{DachwaldSeboldt2005, author = {Dachwald, Bernd and Seboldt, Wolfgang}, title = {Multiple Near-Earth Asteroid Rendezvous and Sample Return Using First Generation Solar Sailcraft}, series = {Acta Astronautica. 57 (2005), H. 11}, journal = {Acta Astronautica. 57 (2005), H. 11}, isbn = {0094-5765}, pages = {864 -- 875}, year = {2005}, language = {en} } @article{DachwaldSeboldt2003, author = {Dachwald, Bernd and Seboldt, Wolfgang}, title = {Solar sailcraft of the first generation mission applications to near-earth asteroids}, year = {2003}, language = {en} } @article{DachwaldSeboldt2005, author = {Dachwald, Bernd and Seboldt, Wolfgang}, title = {Solar Sails for Near- and Medium-Term Scientific Deep Space Missions / W. Sebolt ; B. Dachwald}, series = {In-space propulsion : edited book of proceedings of the 10-IWCP, the 10th International Workshop on Combustion and Propulsion held in Lerici, La Spezia, Italy, 21-25 September 2003 / [ed.: Luigi T. DeLuca]}, journal = {In-space propulsion : edited book of proceedings of the 10-IWCP, the 10th International Workshop on Combustion and Propulsion held in Lerici, La Spezia, Italy, 21-25 September 2003 / [ed.: Luigi T. DeLuca]}, publisher = {SP Lab, Politecnico di Milano}, address = {Milano}, pages = {getr. Z{\"a}hlung . Ill.}, year = {2005}, language = {en} } @article{DachwaldSeboldt2002, author = {Dachwald, Bernd and Seboldt, Wolfgang}, title = {Optimization of Interplanetary Rendezvous Trajectories for Solar Sailcraft Using a Neurocontroller}, series = {A collection of technical papers / AIAA Astrodynamics Specialist Conference : Monterey, California, 5 - 8 August 2002. - Vol. 2}, journal = {A collection of technical papers / AIAA Astrodynamics Specialist Conference : Monterey, California, 5 - 8 August 2002. - Vol. 2}, publisher = {American Institute of Aeronautics and Astronautics}, address = {Reston, Va.}, isbn = {1-56347-549-9}, pages = {1263 -- 1270}, year = {2002}, language = {en} } @article{DachwaldSeboldt2008, author = {Dachwald, Bernd and Seboldt, Wolfgang}, title = {Solar Sails — Propellantless Propulsion for Near- and Medium-Term Deep-Space Missions / W. Seboldt ; B. Dachwald}, series = {Advanced Propulsion Systems and Technologies, Today to 2020 / Claudio Bruno (ed.) ... - (Progress in Astronautics and Aeronautics Series ; 223)}, journal = {Advanced Propulsion Systems and Technologies, Today to 2020 / Claudio Bruno (ed.) ... - (Progress in Astronautics and Aeronautics Series ; 223)}, publisher = {AIAA}, address = {Reston, Va.}, isbn = {978-1-56347-929-8}, pages = {460 S.}, year = {2008}, language = {en} } @article{DachwaldSeboldt2003, author = {Dachwald, Bernd and Seboldt, Wolfgang}, title = {Solar sailcraft of the first generation technology development / Seboldt, Wolfgang ; Dachwald, Bernd}, year = {2003}, language = {en} } @inproceedings{DachwaldSeboldtHaeusler2002, author = {Dachwald, Bernd and Seboldt, Wolfgang and H{\"a}usler, Bernd}, title = {Performance requirements for near-term interplanetary solar sailcraft missions}, series = {6th International AAAF Symposium on Space Propulsion: Propulsion for Space Transportation of the XXIst Century}, booktitle = {6th International AAAF Symposium on Space Propulsion: Propulsion for Space Transportation of the XXIst Century}, pages = {9 Seiten}, year = {2002}, abstract = {Solar sailcraft provide a wide range of opportunities for high-energy low-cost missions. To date, most mission studies require a rather demanding performance that will not be realized by solar sailcraft of the first generation. However, even with solar sailcraft of moderate performance, scientifically relevant missions are feasible. This is demonstrated with a Near Earth Asteroid sample return mission and various planetary rendezvous missions.}, language = {en} } @article{DachwaldSeboldtLoebetal.2008, author = {Dachwald, Bernd and Seboldt, Wolfgang and Loeb, H. W. and Schartner, Karl-Heinz}, title = {Main Belt Asteroid Sample Return Mission Using Solar Electric Propulsion}, series = {Acta Astronautica. 63 (2008), H. 1-4}, journal = {Acta Astronautica. 63 (2008), H. 1-4}, isbn = {0094-5765}, pages = {91 -- 101}, year = {2008}, language = {en} } @inproceedings{DachwaldSeboldtLoebetal.2007, author = {Dachwald, Bernd and Seboldt, Wolfgang and Loeb, Horst W. and Schartner, Karl-Heinz}, title = {A comparison of SEP and NEP for a main belt asteroid sample return mission}, series = {7th International Symposium on Launcher Technologies, Barcelona, Spain, 02-05 April 2007}, booktitle = {7th International Symposium on Launcher Technologies, Barcelona, Spain, 02-05 April 2007}, pages = {1 -- 10}, year = {2007}, abstract = {Innovative interplanetary deep space missions, like a main belt asteroid sample return mission, require ever larger velocity increments (∆V s) and thus ever more demanding propulsion capabilities. Providing much larger exhaust velocities than chemical high-thrust systems, electric low-thrust space-propulsion systems can significantly enhance or even enable such high-energy missions. In 1995, a European-Russian Joint Study Group (JSG) presented a study report on "Advanced Interplanetary Missions Using Nuclear-Electric Propulsion" (NEP). One of the investigated reference missions was a sample return (SR) from the main belt asteroid (19) Fortuna. The envisaged nuclear power plant, Topaz-25, however, could not be realized and also the worldwide developments in space reactor hardware stalled. In this paper, we investigate, whether such a mission is also feasible using a solar electric propulsion (SEP) system and compare our SEP results to corresponding NEP results.}, language = {en} } @article{DachwaldSeboldtLaemmerzahl2008, author = {Dachwald, Bernd and Seboldt, Wolfgang and L{\"a}mmerzahl, W.}, title = {Solar Sail Propulsion: An Enabling Technology for Fundamental Physics Missions}, series = {Lasers, Clocks and Drag Free Control : Exploration of Relativistic Gravity in Space / by Hansj{\"o}rg Dittus ..., eds. - ( Astrophysics and Space Science Library ; 349)}, journal = {Lasers, Clocks and Drag Free Control : Exploration of Relativistic Gravity in Space / by Hansj{\"o}rg Dittus ..., eds. - ( Astrophysics and Space Science Library ; 349)}, publisher = {Springer}, address = {Berlin [u.a.]}, isbn = {978-3-540-34376-9}, pages = {379 -- 398}, year = {2008}, language = {en} } @article{DachwaldSeboldtMacdonaldetal.2005, author = {Dachwald, Bernd and Seboldt, Wolfgang and Macdonald, Malcolm and Mengali, Giovanni and Quatra, Alessandro A. and McInnes, Colin R. and Rios-Reyes, Leonel and Scheerers, Daniel J. and Wie, Bong and G{\"o}rlich, Marianne and Lura, Franz and Diedrich, Benjamin and Baturkin, Volodymyr and Coverstone, Victoria L. and Leipold, Manfred and Garbe, Gregory P.}, title = {Potential Solar Sail Degradation Effects on Trajectory and Attitude Control}, series = {AIAA Guidance, Navigation and Control Conference and Exhibit - AIAA Modeling and Simulation Technologies Conference and Exhibit - AIAA Atmospheric Flight Mechanics Conference and Exhibit : [San Francisco, California, 15 - 18 August 2005 ; papers]. - (AIAA meeting papers on disc ; [10.]2005,16-17)}, journal = {AIAA Guidance, Navigation and Control Conference and Exhibit - AIAA Modeling and Simulation Technologies Conference and Exhibit - AIAA Atmospheric Flight Mechanics Conference and Exhibit : [San Francisco, California, 15 - 18 August 2005 ; papers]. - (AIAA meeting papers on disc ; [10.]2005,16-17)}, publisher = {American Institute of Aeronautics and Astronautics}, address = {Reston, Va.}, isbn = {1-56347-765-3}, pages = {2 CD-ROMs}, year = {2005}, language = {en} } @article{DachwaldSeboldtRichter2006, author = {Dachwald, Bernd and Seboldt, Wolfgang and Richter, L.}, title = {Multiple rendezvous and sample return missions to near-Earth objects using solar sailcraft / Dachwald, B. ; Seboldt, W. ; Richter, L.}, series = {Acta Astronautica. 59 (2006), H. 8-11}, journal = {Acta Astronautica. 59 (2006), H. 8-11}, isbn = {0094-5765}, pages = {768 -- 776}, year = {2006}, language = {en} } @article{DachwaldSeboldtRichter2003, author = {Dachwald, Bernd and Seboldt, Wolfgang and Richter, L.}, title = {Multiple Rendezvous and Sample Return Missions to Near-Earth Asteroids Using Solar Sailcraft}, series = {Proceedings of the Fifth IAA International Conference on Low Cost Planetary Missions : 24 - 26 September 2003, ESTEC, Noordwijk, the Netherlands / [comp. by R. A. Harris]}, journal = {Proceedings of the Fifth IAA International Conference on Low Cost Planetary Missions : 24 - 26 September 2003, ESTEC, Noordwijk, the Netherlands / [comp. by R. A. Harris]}, publisher = {ESA}, address = {Noordwijk}, isbn = {92-9092-853-0}, pages = {351 -- 358}, year = {2003}, language = {en} } @article{DachwaldTsinas1994, author = {Dachwald, Bernd and Tsinas, L.}, title = {A combined neural and genetic learning algorithm / Tsinas, L. ; Dachwald, B.}, series = {Proceedings of the First IEEE Conference on Evolutionary Computation, 1994. IEEE World Congress on Computational Intelligence.}, journal = {Proceedings of the First IEEE Conference on Evolutionary Computation, 1994. IEEE World Congress on Computational Intelligence.}, address = {Orlando, Fl}, isbn = {0-7803-1899-4}, pages = {770 -- 774}, year = {1994}, language = {en} } @article{DachwaldTuryshevDittusetal.2005, author = {Dachwald, Bernd and Turyshev, Slava G. and Dittus, H. and Shao, M. [u.a.]}, title = {Fundamental Physics with the Laser Astrometric Test Of Relativity / S.G. Turyshev ; H. Dittus ; M. Shao ... B.Dachwald ...}, series = {Proceedings of the 39th ESLAB Symposium "Trends in Space Science and Cosmic Vision 2020" : 19 - 21 April 2005, ESTEC, Noordwijk, the Netherlands / European Space Agency. [Comp. by: F. Favata ...] . - (ESA SP ; 588)}, journal = {Proceedings of the 39th ESLAB Symposium "Trends in Space Science and Cosmic Vision 2020" : 19 - 21 April 2005, ESTEC, Noordwijk, the Netherlands / European Space Agency. [Comp. by: F. Favata ...] . - (ESA SP ; 588)}, publisher = {ESA Publ. Div.}, address = {Noordwijk}, isbn = {9290928999}, pages = {8 -- 11}, year = {2005}, language = {en} } @incollection{DachwaldUlamecBiele2013, author = {Dachwald, Bernd and Ulamec, Stephan and Biele, Jens}, title = {Clean in situ subsurface exploration of icy environments in the solar system}, series = {Habitability of other planets and satellites. - (Cellular origin, life in extreme habitats and astrobiology ; 28)}, booktitle = {Habitability of other planets and satellites. - (Cellular origin, life in extreme habitats and astrobiology ; 28)}, publisher = {Springer}, address = {Dordrecht}, isbn = {978-94-007-6545-0 (Druckausgabe)}, pages = {367 -- 397}, year = {2013}, abstract = {"To assess the habitability of the icy environments in the solar system, for example, on Mars, Europa, and Enceladus, the scientific analysis of material embedded in or underneath their ice layers is very important. We consider self-steering robotic ice melting probes to be the best method to cleanly access these environments, that is, in compliance with planetary protection standards. The required technologies are currently developed and tested."}, language = {en} } @incollection{DachwaldUlamecKowalskietal.2023, author = {Dachwald, Bernd and Ulamec, Stephan and Kowalski, Julia and Boxberg, Marc S. and Baader, Fabian and Biele, Jens and K{\"o}mle, Norbert}, title = {Ice melting probes}, series = {Handbook of Space Resources}, booktitle = {Handbook of Space Resources}, editor = {Badescu, Viorel and Zacny, Kris and Bar-Cohen, Yoseph}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-97912-6 (Print)}, doi = {10.1007/978-3-030-97913-3_29}, pages = {955 -- 996}, year = {2023}, abstract = {The exploration of icy environments in the solar system, such as the poles of Mars and the icy moons (a.k.a. ocean worlds), is a key aspect for understanding their astrobiological potential as well as for extraterrestrial resource inspection. On these worlds, ice melting probes are considered to be well suited for the robotic clean execution of such missions. In this chapter, we describe ice melting probes and their applications, the physics of ice melting and how the melting behavior can be modeled and simulated numerically, the challenges for ice melting, and the required key technologies to deal with those challenges. We also give an overview of existing ice melting probes and report some results and lessons learned from laboratory and field tests.}, language = {en} } @article{DachwaldUlamecPostbergetal.2020, author = {Dachwald, Bernd and Ulamec, Stephan and Postberg, Frank and Sohl, Frank and Vera, Jean-Pierre de and Christoph, Waldmann and Lorenz, Ralph D. and Hellard, Hugo and Biele, Jens and Rettberg, Petra}, title = {Key technologies and instrumentation for subsurface exploration of ocean worlds}, series = {Space Science Reviews}, volume = {216}, journal = {Space Science Reviews}, number = {Art. 83}, publisher = {Springer}, address = {Dordrecht}, issn = {1572-9672}, doi = {10.1007/s11214-020-00707-5}, pages = {45}, year = {2020}, abstract = {In this chapter, the key technologies and the instrumentation required for the subsurface exploration of ocean worlds are discussed. The focus is laid on Jupiter's moon Europa and Saturn's moon Enceladus because they have the highest potential for such missions in the near future. The exploration of their oceans requires landing on the surface, penetrating the thick ice shell with an ice-penetrating probe, and probably diving with an underwater vehicle through dozens of kilometers of water to the ocean floor, to have the chance to find life, if it exists. Technologically, such missions are extremely challenging. The required key technologies include power generation, communications, pressure resistance, radiation hardness, corrosion protection, navigation, miniaturization, autonomy, and sterilization and cleaning. Simpler mission concepts involve impactors and penetrators or - in the case of Enceladus - plume-fly-through missions.}, language = {en} } @article{DachwaldWi2007, author = {Dachwald, Bernd and Wi, Bong}, title = {Solar Sail Kinetic Energy Impactor Trajectory Optimization for an Asteroid-Deflection Mission}, series = {Journal of Spacecraft and Rockets. 44 (2007), H. 4}, journal = {Journal of Spacecraft and Rockets. 44 (2007), H. 4}, isbn = {0022-4650}, pages = {755 -- 764}, year = {2007}, language = {en} } @article{DachwaldWie2005, author = {Dachwald, Bernd and Wie, Bong}, title = {Solar Sail Trajectory Optimization for Intercepting, Impacting, and Deflecting Near-Earth Asteroids}, series = {AIAA Guidance, Navigation and Control Conference and Exhibit - AIAA Modeling and Simulation Technologies Conference and Exhibit - AIAA Atmospheric Flight Mechanics Conference and Exhibit : [San Francisco, California, 15 - 18 August 2005 ; papers]. - (AIAA meeting papers on disc ; [10.]2005,16-17)}, journal = {AIAA Guidance, Navigation and Control Conference and Exhibit - AIAA Modeling and Simulation Technologies Conference and Exhibit - AIAA Atmospheric Flight Mechanics Conference and Exhibit : [San Francisco, California, 15 - 18 August 2005 ; papers]. - (AIAA meeting papers on disc ; [10.]2005,16-17)}, publisher = {American Institute of Aeronautics and Astronautics}, address = {Reston, Va.}, isbn = {1-56347-765-3}, pages = {2 CD-ROMs}, year = {2005}, language = {en} } @inproceedings{DachwaldWurm2009, author = {Dachwald, Bernd and Wurm, P.}, title = {Design concept and modeling of an advanced solar photon thruster}, series = {Advances in the Astronautical Sciences}, booktitle = {Advances in the Astronautical Sciences}, publisher = {American Astronautical Society}, address = {San Diego, Calif.}, isbn = {978-087703554-1}, issn = {00653438}, pages = {723 -- 740}, year = {2009}, abstract = {The so-called "compound solar sail", also known as "Solar Photon Thruster" (SPT), holds the potential of providing significant performance advantages over the flat solar sail. Previous SPT design concepts, however, do not consider shadowing effects and multiple reflections of highly concentrated solar radiation that would inevitably destroy the gossamer sail film. In this paper, we propose a novel advanced SPT (ASPT) design concept that does not suffer from these oversimplifications. We present the equations that describe the thrust force acting on such a sail system and compare its performance with respect to the conventional flat solar sail.}, language = {en} } @inproceedings{DachwaldWurm2009, author = {Dachwald, Bernd and Wurm, P.}, title = {Mission analysis for an advanced solar photon thruster}, series = {60th International Astronautical Congress 2009, IAC 2009}, volume = {8}, booktitle = {60th International Astronautical Congress 2009, IAC 2009}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {978-161567908-9}, pages = {6838 -- 6851}, year = {2009}, abstract = {The so-called "compound solar sail", also known as "Solar Photon Thruster" (SPT), is a solar sail design concept, for which the two basic functions of the solar sail, namely light collection and thrust direction, are uncoupled. In this paper, we introduce a novel SPT concept, termed the Advanced Solar Photon Thruster (ASPT). This model does not suffer from the simplified assumptions that have been made for the analysis of compound solar sails in previous studies. We present the equations that describe the force, which acts on the ASPT. After a detailed design analysis, the performance of the ASPT with respect to the conventional flat solar sail (FSS) is investigated for three interplanetary mission scenarios: An Earth-Venus rendezvous, where the solar sail has to spiral towards the Sun, an Earth-Mars rendezvous, where the solar sail has to spiral away from the Sun, and an Earth-NEA rendezvous (to near-Earth asteroid 1996FG3), where a large orbital eccentricity change is required. The investigated solar sails have realistic near-term characteristic accelerations between 0.1 and 0.2mm/s2. Our results show that a SPT is not superior to the flat solar sail unless very idealistic assumptions are made.}, language = {en} } @article{DachwaldWurm2011, author = {Dachwald, Bernd and Wurm, Patrick}, title = {Mission analysis and performance comparison for an Advanced Solar Photon Thruster}, series = {Advances in Space Research}, volume = {48}, journal = {Advances in Space Research}, number = {11}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0273-1177}, pages = {1858 -- 1868}, year = {2011}, language = {en} } @inproceedings{DachwaldXuFeldmannetal.2011, author = {Dachwald, Bernd and Xu, Changsheng and Feldmann, Marco and Plescher, Engelbert}, title = {IceMole : Development of a novel subsurface ice probe and testing of the first prototype on the Morteratsch Glacier}, series = {EGU General Assembly 2011 Vienna | Austria | 03 - 08 April 2011}, booktitle = {EGU General Assembly 2011 Vienna | Austria | 03 - 08 April 2011}, year = {2011}, abstract = {We present the novel concept of a combined drilling and melting probe for subsurface ice research. This probe, named "IceMole", is currently developed, built, and tested at the FH Aachen University of Applied Sciences' Astronautical Laboratory. Here, we describe its first prototype design and report the results of its field tests on the Swiss Morteratsch glacier. Although the IceMole design is currently adapted to terrestrial glaciers and ice shields, it may later be modified for the subsurface in-situ investigation of extraterrestrial ice, e.g., on Mars, Europa, and Enceladus. If life exists on those bodies, it may be present in the ice (as life can also be found in the deep ice of Earth).}, language = {en} } @inproceedings{DachwaldXuFeldmannetal.2011, author = {Dachwald, Bernd and Xu, Changsheng and Feldmann, Marco and Plescher, Engelbert and Digel, Ilya and Artmann, Gerhard}, title = {Development and testing of a subsurface probe for detection of life in deep ice : [abstract]}, year = {2011}, abstract = {We present the novel concept of a combined drilling and melting probe for subsurface ice research. This probe, named "IceMole", is currently developed, built, and tested at the FH Aachen University of Applied Sciences' Astronautical Laboratory. Here, we describe its first prototype design and report the results of its field tests on the Swiss Morteratsch glacier. Although the IceMole design is currently adapted to terrestrial glaciers and ice shields, it may later be modified for the subsurface in-situ investigation of extraterrestrial ice, e.g., on Mars, Europa, and Enceladus. If life exists on those bodies, it may be present in the ice (as life can also be found in the deep ice of Earth).}, subject = {Eisschicht}, language = {en} } @article{DadfarCamozziDarguzyteetal.2020, author = {Dadfar, Dryed Mohammadali and Camozzi, Denise and Darguzyte, Milita and Roemhild, Karolin and Varvar{\`a}, Paola and Metselaar, Josbert and Banala, Srinivas and Straub, Marcel and G{\"u}ver, Nihan and Engelmann, Ulrich M. and Slabu, Ioana and Buhl, Miriam and Leusen, Jan van and K{\"o}gerler, Paul and Hermanns-Sachweh, Benita and Schulz, Volkmar and Kiessling, Fabian and Lammers, Twan}, title = {Size-isolation of superparamagnetic iron oxide nanoparticles improves MRI, MPI and hyperthermia performance}, series = {Journal of Nanobiotechnology}, volume = {18}, journal = {Journal of Nanobiotechnology}, number = {Article number 22}, publisher = {Nature Portfolio}, issn = {1477-3155}, doi = {10.1186/s12951-020-0580-1}, pages = {1 -- 13}, year = {2020}, abstract = {Superparamagnetic iron oxide nanoparticles (SPION) are extensively used for magnetic resonance imaging (MRI) and magnetic particle imaging (MPI), as well as for magnetic fluid hyperthermia (MFH). We here describe a sequential centrifugation protocol to obtain SPION with well-defined sizes from a polydisperse SPION starting formulation, synthesized using the routinely employed co-precipitation technique. Transmission electron microscopy, dynamic light scattering and nanoparticle tracking analyses show that the SPION fractions obtained upon size-isolation are well-defined and almost monodisperse. MRI, MPI and MFH analyses demonstrate improved imaging and hyperthermia performance for size-isolated SPION as compared to the polydisperse starting mixture, as well as to commercial and clinically used iron oxide nanoparticle formulations, such as Resovist® and Sinerem®. The size-isolation protocol presented here may help to identify SPION with optimal properties for diagnostic, therapeutic and theranostic applications.}, language = {en} } @article{DahlSuttrop1998, author = {Dahl, G{\"u}nter and Suttrop, F.}, title = {Engine control and low-NO(x) combustion for hydrogen fuelled aircraft gas turbines}, series = {International Journal of Hydrogen Energy. 23 (1998), H. 8}, journal = {International Journal of Hydrogen Energy. 23 (1998), H. 8}, isbn = {0360-3199}, pages = {695 -- 704}, year = {1998}, language = {en} } @inproceedings{DalguerChurilovButenwegetal.2014, author = {Dalguer, Luis A. and Churilov, Sergey and Butenweg, Christoph and Renault, Philippe and Hyun, An Jun}, title = {Dynamic analysis of a reinforced concrete electrical nuclear building of SMART 2013 project subjected to earthquake excitation using ABAQUS}, series = {Workshop SMART2013 : Paris, France, November 25th - 27th, 2014}, booktitle = {Workshop SMART2013 : Paris, France, November 25th - 27th, 2014}, organization = {Workshop SMART2013 <2014, Paris>}, pages = {1 -- 12}, year = {2014}, language = {en} } @inproceedings{DalguerRenaultChurilovetal.2016, author = {Dalguer, Luis A. and Renault, Philippe and Churilov, Sergey and Butenweg, Christoph}, title = {Evaluation of fragility curves for a three-storey-reinforced-concrete mock-up of SMART 2013 project}, series = {Transactions, SMiRT-23 : 23rd Conference on Structural Mechanics in Reactor Technology : Manchester, United Kingdom - August 10-14, 2015}, booktitle = {Transactions, SMiRT-23 : 23rd Conference on Structural Mechanics in Reactor Technology : Manchester, United Kingdom - August 10-14, 2015}, organization = {Conference on Structural Mechanics in Reactor Technology <23, 2015, Manchester>}, pages = {1 -- 9}, year = {2016}, language = {en} } @article{DallasSalphatiGomezZepedaetal.2016, author = {Dallas, Shannon and Salphati, Laurent and Gomez-Zepeda, David and Wanek, Thomas and Chen, Liangfu and Chu, Xiaoyan and Kunta, Jeevan and Mezler, Mario and Menet, Marie-Claude and Chasseigneaux, Stephanie and Decl{\`e}ves, Xavier and Langer, Oliver and Pierre, Esaie and DiLoreto, Karen and Hoft, Carolin and Laplanche, Loic and Pang, Jodie and Pereira, Tony and Andonian, Clara and Simic, Damir and Rode, Anja and Yabut, Jocelyn and Zhang, Xiaolin and Scheer, Nico}, title = {Generation and Characterization of a Breast Cancer Resistance Protein Humanized Mouse Model}, series = {Molecular Pharmacology}, volume = {89}, journal = {Molecular Pharmacology}, number = {5}, publisher = {ASPET}, address = {Bethesda, Md.}, issn = {1521-0111}, doi = {10.1124/mol.115.102079}, pages = {492 -- 504}, year = {2016}, abstract = {Breast cancer resistance protein (BCRP) is expressed in various tissues, such as the gut, liver, kidney and blood brain barrier (BBB), where it mediates the unidirectional transport of substrates to the apical/luminal side of polarized cells. Thereby BCRP acts as an efflux pump, mediating the elimination or restricting the entry of endogenous compounds or xenobiotics into tissues and it plays important roles in drug disposition, efficacy and safety. Bcrp knockout mice (Bcrp-/-) have been used widely to study the role of this transporter in limiting intestinal absorption and brain penetration of substrate compounds. Here we describe the first generation and characterization of a mouse line humanized for BCRP (hBCRP), in which the mouse coding sequence from the start to stop codon was replaced with the corresponding human genomic region, such that the human transporter is expressed under control of the murine Bcrp promoter. We demonstrate robust human and loss of mouse BCRP/Bcrp mRNA and protein expression in the hBCRP mice and the absence of major compensatory changes in the expression of other genes involved in drug metabolism and disposition. Pharmacokinetic and brain distribution studies with several BCRP probe substrates confirmed the functional activity of the human transporter in these mice. Furthermore, we provide practical examples for the use of hBCRP mice to study drug-drug interactions (DDIs). The hBCRP mouse is a promising model to study the in vivo role of human BCRP in limiting absorption and BBB penetration of substrate compounds and to investigate clinically relevant DDIs involving BCRP.}, language = {en} } @article{DammErlerHillenetal.2011, author = {Damm, Alexander and Erler, Andr{\´e} and Hillen, Walter and Meroni, Michele and Schaepman, Michael E. and Verhoef, Wout and Rascher, Uwe}, title = {Modeling the impact of spectral sensor configurations on the FLD retrieval accuracy of sun-induced chlorophyll fluorescence}, series = {Remote Sensing of Environment}, volume = {115}, journal = {Remote Sensing of Environment}, number = {8}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {0034-4257}, pages = {1882 -- 1892}, year = {2011}, language = {en} } @article{DammSauerbornFendetal.2017, author = {Damm, Marc Andr{\´e} and Sauerborn, Markus and Fend, Thomas and Herrmann, Ulf}, title = {Optimisation of a urea selective catalytic reduction system with a coated ceramic mixing element}, series = {Journal of ceramic science and technology}, volume = {8}, journal = {Journal of ceramic science and technology}, number = {1}, publisher = {G{\"o}ller}, address = {Baden-Baden}, isbn = {2190-9385 (Print)}, issn = {2190-9385 (Online)}, doi = {10.4416/JCST2016-00056}, pages = {19 -- 24}, year = {2017}, language = {en} } @inproceedings{DammRahierRitzetal.2013, author = {Damm, Sebastian and Rahier, Michael and Ritz, Thomas and Sch{\"a}fer, Thomas}, title = {Architecture for platform- and hardware-independent mesh networks : how to unify the channels}, series = {ICSNC 2013 : The Eighth International Conference on Systems and Networks Communications ; October 27, 2013 to October 31, 2013, Venice Italy}, booktitle = {ICSNC 2013 : The Eighth International Conference on Systems and Networks Communications ; October 27, 2013 to October 31, 2013, Venice Italy}, editor = {Davoli, Renzo}, publisher = {Curran Associates}, address = {Red Hook, NY}, isbn = {978-1-61208-305-6}, pages = {131 -- 134}, year = {2013}, abstract = {This paper will prove that mesh networks among different platforms and hardware channels can help to channel valuable information even if public telecommunication infrastructure is not available due to arbitrary reasons. Therefore, results of a simulation for mesh networks on mass events will be provided, followed by the developed architecture and an outlook on future research. The developed architecture is currently being implemented and field tested on mass events.}, language = {en} } @inproceedings{DammRitzStrauch2011, author = {Damm, Sebastian and Ritz, Thomas and Strauch, Jakob}, title = {Adaption of archetype patterns for mobile cloud-based business apps}, series = {2011 IEEE International Conference on Pervasive Computing and Communications workshops (PerCom workshops 2011) : Seattle, Washington, USA, 21 - 25 March 2011}, booktitle = {2011 IEEE International Conference on Pervasive Computing and Communications workshops (PerCom workshops 2011) : Seattle, Washington, USA, 21 - 25 March 2011}, publisher = {IEEE Service Center}, address = {Piscataway, NJ}, isbn = {978-1-61284-938-6 (Print)}, doi = {10.1109/PERCOMW.2011.5766849}, pages = {100 -- 105}, year = {2011}, language = {en} } @article{Damrau1999, author = {Damrau, Karin}, title = {Beyond Solidity - Inventions, Spaces and Concepts for the Elements of Air and Water}, series = {Architectural design : AD. 69 (1999), H. 3-4}, journal = {Architectural design : AD. 69 (1999), H. 3-4}, isbn = {0003-8504}, pages = {22 -- 33}, year = {1999}, language = {en} } @article{Damrau2000, author = {Damrau, Karin}, title = {Fantastic Spatial Combinations in Film}, series = {Architectural design : AD. 70 (2000), H. 1}, journal = {Architectural design : AD. 70 (2000), H. 1}, isbn = {0003-8504}, pages = {58 -- 61}, year = {2000}, language = {en} } @article{DanhoNaithaniSasakietal.1980, author = {Danho, Waleed and Naithani, Vinod K. and Sasaki, Andr{\´e} N. and F{\"o}hles, Joseph and Berndt, Heinz and B{\"u}llesbach, Erika E. and Zahn, H.}, title = {Human proinsulin, VII : synthesis of two protected peptides corresponding to the sequences 1—45 and 46—86 of the prohormone}, series = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie}, volume = {361}, journal = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie}, number = {1}, issn = {1437-4315}, doi = {10.1515/bchm2.1980.361.1.857}, pages = {857 -- 863}, year = {1980}, language = {en} } @article{DankelmannHellwigVolkmann2009, author = {Dankelmann, Peter and Hellwig, Angelika and Volkmann, Lutz}, title = {Inverse degree and edge-connectivity}, series = {Discrete mathematics}, volume = {Vol. 309}, journal = {Discrete mathematics}, number = {Iss. 9}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1872-681X (E-Journal); 0012-365X (Print)}, pages = {2943 -- 2947}, year = {2009}, language = {en} } @article{DankelmannHellwigVolkmann2007, author = {Dankelmann, Peter and Hellwig, Angelika and Volkmann, Lutz}, title = {On the connectivity of diamond-free graphs}, series = {Discrete applied mathematics}, volume = {Vol. 155}, journal = {Discrete applied mathematics}, number = {Iss. 16}, issn = {0166-218X (E-Journal); 1872-6771 (E-Journal); 0166-218X (Print)}, pages = {2111 -- 2117}, year = {2007}, language = {en} } @inproceedings{DannenSchindelePruemmeretal.2022, author = {Dannen, Tammo and Schindele, Benedikt and Pr{\"u}mmer, Marcel and Arntz, Kristian and Bergs, Thomas}, title = {Methodology for the self-optimizing determination of additive manufacturing process eligibility and optimization potentials in toolmaking}, series = {Procedia CIRP Leading manufacturing systems transformation - Proceedings of the 55th CIRP Conference on Manufacturing Systems 2022}, volume = {107}, booktitle = {Procedia CIRP Leading manufacturing systems transformation - Proceedings of the 55th CIRP Conference on Manufacturing Systems 2022}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2212-8271}, doi = {10.1016/j.procir.2022.05.188}, pages = {1539 -- 1544}, year = {2022}, abstract = {Additive Manufacturing (AM) of metallic workpieces faces a continuously rising technological relevance and market size. Producing complex or highly strained unique workpieces is a significant field of application, making AM highly relevant for tool components. Its successful economic application requires systematic workpiece based decisions and optimizations. Considering geometric and technological requirements as well as the necessary post-processing makes deciding effortful and requires in-depth knowledge. As design is usually adjusted to established manufacturing, associated technological and strategic potentials are often neglected. To embed AM in a future proof industrial environment, software-based self-learning tools are necessary. Integrated into production planning, they enable companies to unlock the potentials of AM efficiently. This paper presents an appropriate methodology for the analysis of process-specific AM-eligibility and optimization potential, added up by concrete optimization proposals. For an integrated workpiece characterization, proven methods are enlarged by tooling-specific figures. The first stage of the approach specifies the model's initialization. A learning set of tooling components is described using the developed key figure system. Based on this, a set of applicable rules for workpiece-specific result determination is generated through clustering and expert evaluation. Within the following application stage, strategic orientation is quantified and workpieces of interest are described using the developed key figures. Subsequently, the retrieved information is used for automatically generating specific recommendations relying on the generated ruleset of stage one. Finally, actual experiences regarding the recommendations are gathered within stage three. Statistic learning transfers those to the generated ruleset leading to a continuously deepening knowledge base. This process enables a steady improvement in output quality.}, language = {en} }