@article{McArdellBarteltKowalski2007, author = {McArdell, Brian W. and Bartelt, Perry and Kowalski, Julia}, title = {Field observations of basal forces and fluid pore pressure in a debris flow}, series = {Geophysical Research Letters (GRL)}, volume = {34}, journal = {Geophysical Research Letters (GRL)}, number = {7}, isbn = {0094-8276}, year = {2007}, abstract = {Using results from an 8 m2 instrumented force plate we describe field measurements of normal and shear stresses, and fluid pore pressure for a debris flow. The flow depth increased from 0.1 to 1 m within the first 12 s of flow front arrival, remained relatively constant until 100 s, and then gradually decreased to 0.5 m by 600 s. Normal and shear stresses and pore fluid pressure varied in-phase with the flow depth. Calculated bulk densities are ρb = 2000-2250 kg m-3 for the bulk flow and ρf = 1600-1750 kg m-3 for the fluid phase. The ratio of effective normal stress to shear stress yields a Coulomb basal friction angle of ϕ = 26° at the flow front. We did not find a strong correlation between the degree of agitation in the flow, estimated using the signal from a geophone on the force plate, and an assumed dynamic pore fluid pressure. Our data support the idea that excess pore-fluid pressures are long lived in debris flows and therefore contribute to their unusual mobility.}, language = {en} } @inproceedings{LoebSchartnerDachwaldetal.2007, author = {Loeb, Horst Wolfgang and Schartner, Karl-Heinz and Dachwald, Bernd and Seboldt, Wolfgang}, title = {SEP-Sample return from a main belt asteroid}, series = {30th International Electric Propulsion Conference}, booktitle = {30th International Electric Propulsion Conference}, pages = {1 -- 11}, year = {2007}, abstract = {By DLR-contact, sample return missions to the large main-belt asteroid "19, Fortuna" have been studied. The mission scenario has been based on three ion thrusters of the RIT-22 model, which is presently under space qualification, and on solar arrays equipped with triple-junction GaAs solar cells. After having designed the spacecraft, the orbit-to-orbit trajectories for both, a one-way SEP mission with a chemical sample return and an all-SEP return mission, have been optimized using a combination of artificial neural networks with evolutionary algorithms. Additionally, body-to-body trajectories have been investigated within a launch period between 2012 and 2015. For orbit-to-orbit calculation, the launch masses of the hybrid mission and of the all-SEP mission resulted in 2.05 tons and 1.56 tons, respectively, including a scientific payload of 246 kg. For the related transfer durations 4.14 yrs and 4.62 yrs were obtained. Finally, a comparison between the mission scenarios based on SEP and on NEP have been carried out favouring clearly SEP.}, language = {en} } @article{LeyPlescherScholzetal.2007, author = {Ley, Wilfried and Plescher, Engelbert and Scholz, Artur and Piepenbrock, Johannes}, title = {COMPASS-1 picosatellite project / Ley, Wilfried ; Plescher, Engelbert ; Scholz, Artur ; Piepenbrock, Johannes}, series = {Small satellites for earth observation : digest of the 6th International symposium of the International Academy of Astronautics, Berlin, April 23 - 26, 2007 / ed. by Rainer Sandau; Hans-Peter R{\"o}ser; Arnoldo Valenzuela}, journal = {Small satellites for earth observation : digest of the 6th International symposium of the International Academy of Astronautics, Berlin, April 23 - 26, 2007 / ed. by Rainer Sandau; Hans-Peter R{\"o}ser; Arnoldo Valenzuela}, publisher = {Wissenschaft und Technik Verl.}, address = {Berlin}, isbn = {9783896855718}, pages = {147 -- 150}, year = {2007}, language = {en} } @inproceedings{KowalskiBarteltMcElwaine2007, author = {Kowalski, Julia and Bartelt, Perry and McElwaine, J.}, title = {Two-phase debris flow modeling}, series = {Geophysical Research Abstracts}, booktitle = {Geophysical Research Abstracts}, year = {2007}, language = {en} } @article{HennPolaczek2007, author = {Henn, Gudrun and Polaczek, Christa}, title = {Studienerfolg in den Ingenieurwissenschaften}, series = {Das Hochschulwesen : HSW ; Forum f{\"u}r Hochschulforschung, -praxis und -politik}, volume = {55}, journal = {Das Hochschulwesen : HSW ; Forum f{\"u}r Hochschulforschung, -praxis und -politik}, number = {5}, issn = {0018-2974}, pages = {144 -- 147}, year = {2007}, language = {de} } @article{GerhardtSchoenwaldKonrath2007, author = {Gerhardt, Hans Joachim and Sch{\"o}nwald, J. and Konrath, B.}, title = {Verwendung von Leichtgas bei Brandsimulationen - unzul{\"a}ssig oder sinnvoll?}, series = {VFDB-Zeitschrift : Forschung, Technik und Management im Brandschutz. 56 (2007), H. 1}, journal = {VFDB-Zeitschrift : Forschung, Technik und Management im Brandschutz. 56 (2007), H. 1}, isbn = {0042-1804}, pages = {29 -- 31}, year = {2007}, language = {de} } @article{FunkeRobinson2007, author = {Funke, Harald and Robinson, A. E.}, title = {Development of a new test rig for a micro scale hydrogen combustion chamber}, series = {Proceedings of the 2nd European Conference for Aero-Space Sciences : July 1 - 6, 2007, Brussels, Belgium}, journal = {Proceedings of the 2nd European Conference for Aero-Space Sciences : July 1 - 6, 2007, Brussels, Belgium}, publisher = {-}, pages = {1 -- 8}, year = {2007}, language = {en} } @book{Esch2007, author = {Esch, Thomas}, title = {Verbrennungstechnik. - 6. Aufl., [Umdruck]. - (Angewandte Thermodynamik und Verbrennungstechnik)}, publisher = {Fachhochschule Aachen, Lehr- und Forschungsgebiet Thermodynamik und Verbrennungstechnik}, address = {Aachen}, pages = {Getr. Z{\"a}hlung : Ill. und graph. Darst.}, year = {2007}, language = {de} } @book{Esch2007, author = {Esch, Thomas}, title = {Experimentelle Untersuchungen an Antriebssystemen von Kraft-, Luft- und Raumfahrzeugen : Vorlesungsumdruck. Bd. 1}, publisher = {Fachhochschule Aachen, Lehr- und Forschungsgebiet Thermodynamik und Verbrennungstechnik}, address = {Aachen}, pages = {Getr. Z{\"a}hlung : zahlr. Ill. und graph. Darst.}, year = {2007}, language = {de} } @book{Esch2007, author = {Esch, Thomas}, title = {Experimentelle Untersuchungen an Antriebssystemen von Kraft-, Luft- und Raumfahrzeugen : Vorlesungsumdruck. Bd. 2}, publisher = {Fachhochschule Aachen, Lehr- und Forschungsgebiet Thermodynamik und Verbrennungstechnik}, address = {Aachen}, pages = {Getr. Z{\"a}hlung : zahlr. Ill. und graph. Darst.}, year = {2007}, language = {de} }