@article{ChristenKowalskiBartelt2010, author = {Christen, Marc and Kowalski, Julia and Bartelt, Perry}, title = {RAMMS: Numerical simulation of dense snow avalanches in three-dimensional terrain}, series = {Cold Regions Science and Technology}, volume = {63}, journal = {Cold Regions Science and Technology}, number = {1-2}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1872-7441}, doi = {10.1016/j.coldregions.2010.04.005}, pages = {1 -- 14}, year = {2010}, abstract = {Numerical avalanche dynamics models have become an essential part of snow engineering. Coupled with field observations and historical records, they are especially helpful in understanding avalanche flow in complex terrain. However, their application poses several new challenges to avalanche engineers. A detailed understanding of the avalanche phenomena is required to construct hazard scenarios which involve the careful specification of initial conditions (release zone location and dimensions) and definition of appropriate friction parameters. The interpretation of simulation results requires an understanding of the numerical solution schemes and easy to use visualization tools. We discuss these problems by presenting the computer model RAMMS, which was specially designed by the SLF as a practical tool for avalanche engineers. RAMMS solves the depth-averaged equations governing avalanche flow with accurate second-order numerical solution schemes. The model allows the specification of multiple release zones in three-dimensional terrain. Snow cover entrainment is considered. Furthermore, two different flow rheologies can be applied: the standard Voellmy-Salm (VS) approach or a random kinetic energy (RKE) model, which accounts for the random motion and inelastic interaction between snow granules. We present the governing differential equations, highlight some of the input and output features of RAMMS and then apply the models with entrainment to simulate two well-documented avalanche events recorded at the Vall{\´e}e de la Sionne test site.}, language = {en} } @book{Cordewiner1982, author = {Cordewiner, Hans-Josef}, title = {Einsatz und Entwicklung der Datenverarbeitung im Bereich der Konstruktion}, publisher = {Zentralbibliothek d. Kernforschungsanlage}, address = {J{\"u}lich}, pages = {I, 31 S. : Ill., graph. Darst.}, year = {1982}, language = {de} } @book{Cordewiner1979, author = {Cordewiner, Hans-Josef}, title = {Numerische Berechnung des Tritium-Verhaltens von Kugelhaufenreaktoren am Beispiel des AVR-Reaktors}, publisher = {Zentralbibliothek d. Kernforschungsanlage J{\"u}lich GmbH}, address = {J{\"u}lich}, pages = {96, 19 S. : 16 graph. Darst.}, year = {1979}, language = {de} } @book{Cordewiner1983, author = {Cordewiner, Hans-Josef}, title = {Fertigung und Test der Metallfaltbelaege des TEXTOR-Vakuumgefaesses}, publisher = {Kernforschungsanlage Juelich GmbH}, address = {J{\"u}lich}, year = {1983}, language = {de} } @book{CordewinerSchoernerKochetal.1983, author = {Cordewiner, Hans-Josef and Schoerner, M. and Koch, R. and Bachner, E.}, title = {Untersuchungen zum Einsatz eines CAD-Systems fuer den Konstruktionsbereich der Zentralabteilung Allgemeine Technologie der Kernforschungsanlage Juelich}, publisher = {Gesellschaft fuer Elektronische Informationsverarbeitung}, address = {Aachen}, year = {1983}, language = {de} } @inproceedings{Czupalla2017, author = {Czupalla, Markus}, title = {Pflanzen oder Maschinen - was l{\"a}ßt uns auf dem Mars {\"u}berleben?}, series = {{\"U}berleben im Weltraum. Auf dem Weg zu neuen Grenzen. 21. Berliner Kolloquium der Daimler und Benz Stiftung 24. Mai 2017}, booktitle = {{\"U}berleben im Weltraum. Auf dem Weg zu neuen Grenzen. 21. Berliner Kolloquium der Daimler und Benz Stiftung 24. Mai 2017}, pages = {12 -- 12}, year = {2017}, language = {de} } @article{Czupalla2017, author = {Czupalla, Markus}, title = {Ein Garten im Weltraum}, series = {Spektrum der Wissenschaft}, journal = {Spektrum der Wissenschaft}, publisher = {Spektrum-der-Wiss.-Verl.-Ges.}, address = {Heidelberg}, year = {2017}, language = {de} } @article{CzupallaHorneckBlome2005, author = {Czupalla, Markus and Horneck, G. and Blome, Hans-Joachim}, title = {The conceptual design of a hybrid life support system based on the evaluation and comparison of terrestrial testbeds}, series = {Advances in Space Research}, volume = {35}, journal = {Advances in Space Research}, number = {9}, isbn = {0273-1177}, pages = {1609 -- 1620}, year = {2005}, language = {en} } @article{Dachwald2004, author = {Dachwald, Bernd}, title = {Evolutionary Neurocontrol: A Smart Method for Global Optimization of Low-Thrust Trajectories}, series = {22nd AIAA Applied Aerodynamics Conference and Exhibit - AIAA/AAS Astrodynamics Specialist Conference and Exhibit - AIAA Guidance, Navigation, and Control Conference and Exhibit - AIAA Modeling and Simulation Technologies Conference and Exhibit - AIAA Atmospheric Flight Mechanics Conference and Exhibit : 16 - 19 August 2004, Providence, Rhode Island / American Institute of Aeronautics and Astronautics. - (AIAA meeting papers on disc ; 2004,14-15)}, journal = {22nd AIAA Applied Aerodynamics Conference and Exhibit - AIAA/AAS Astrodynamics Specialist Conference and Exhibit - AIAA Guidance, Navigation, and Control Conference and Exhibit - AIAA Modeling and Simulation Technologies Conference and Exhibit - AIAA Atmospheric Flight Mechanics Conference and Exhibit : 16 - 19 August 2004, Providence, Rhode Island / American Institute of Aeronautics and Astronautics. - (AIAA meeting papers on disc ; 2004,14-15)}, publisher = {American Inst. of Aeronautics and Astronautics}, address = {Reston, Va.}, pages = {2 CD-ROMs}, year = {2004}, language = {en} } @article{Dachwald2005, author = {Dachwald, Bernd}, title = {Optimization of very-low-thrust trajectories using evolutionary neurocontrol}, series = {Acta Astronautica}, volume = {57}, journal = {Acta Astronautica}, number = {2-8}, publisher = {Elsevier}, address = {Amsterdam [u.a.]}, isbn = {1879-2030}, pages = {175 -- 185}, year = {2005}, abstract = {Searching optimal interplanetary trajectories for low-thrust spacecraft is usually a difficult and time-consuming task that involves much experience and expert knowledge in astrodynamics and optimal control theory. This is because the convergence behavior of traditional local optimizers, which are based on numerical optimal control methods, depends on an adequate initial guess, which is often hard to find, especially for very-low-thrust trajectories that necessitate many revolutions around the sun. The obtained solutions are typically close to the initial guess that is rarely close to the (unknown) global optimum. Within this paper, trajectory optimization problems are attacked from the perspective of artificial intelligence and machine learning. Inspired by natural archetypes, a smart global method for low-thrust trajectory optimization is proposed that fuses artificial neural networks and evolutionary algorithms into so-called evolutionary neurocontrollers. This novel method runs without an initial guess and does not require the attendance of an expert in astrodynamics and optimal control theory. This paper details how evolutionary neurocontrol works and how it could be implemented. The performance of the method is assessed for three different interplanetary missions with a thrust to mass ratio <0.15mN/kg (solar sail and nuclear electric).}, language = {en} }