@misc{GamgamiCzupallaGarciaetal.2016, author = {Gamgami, Farid and Czupalla, Markus and Garcia, Antonio and Agnolon, David}, title = {From planetary transits to spacecraft design: achieving PLATO's pointing performance}, series = {A7. Symposium on technological Requirement for future space astronomy and solar-system science missions}, journal = {A7. Symposium on technological Requirement for future space astronomy and solar-system science missions}, year = {2016}, abstract = {In the last decades, several hundred exoplanets could be detected thanks to space-based observatories, namely CNES' COROT and NASA's Kepler. To expand this quest ESA plans to launch CHEOPS as the f irst small class mission in the cosmic visions program (S1) and PLATO as the 3rd medium class mission, so called M3 . PLATO's primary objective is the detection of Earth like Exoplanets orbiting solar type stars in the habitable zone and characterisation of their bulk properties. This is possible by precise lightcurve measurement via 34 cameras. That said it becomes obvious that accurate pointing is key to achieve the required signal to noise ratio for positive transit detection. The paper will start with a comprehensive overview of PLATO's mission objectives and mission architecture. Hereafter, special focus will be devoted to PLATO's pointing requirements. Understanding the very nature of PLATO's pointing requirements is essential to derive a design baseline to achieve the required performance. The PLATO frequency domain is of particular interest, ranging from 40 mHz to 3 Hz. Due to the very different time-scales involved, the spectral pointing requirement is decomposed into a high frequency part dominated by the attitude control system and the low frequency part dominated by the thermo-elastic properties of the spacecraft's configuration. Both pose stringent constraints on the overall design as well as technology properties to comply with the derived requirements and thus assure a successful mission.}, language = {en} } @article{GazdaMaurischat2020, author = {Gazda, Quentin and Maurischat, Andreas}, title = {Special functions and Gauss-Thakur sums in higher rank and dimension}, publisher = {De Gruyter}, address = {Berlin}, pages = {26 Seiten}, year = {2020}, language = {en} } @inproceedings{GehlerOberBloebaumDachwald2009, author = {Gehler, M. and Ober-Bl{\"o}baum, S. and Dachwald, Bernd}, title = {Application of discrete mechanics and optimal control to spacecraft in non-keplerian motion around small solar system bodies}, series = {Procceedings of the 60th International Astronautical Congress}, booktitle = {Procceedings of the 60th International Astronautical Congress}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {978-161567908-9}, pages = {1360 -- 1371}, year = {2009}, abstract = {Prolonged operations close to small solar system bodies require a sophisticated control logic to minimize propellant mass and maximize operational efficiency. A control logic based on Discrete Mechanics and Optimal Control (DMOC) is proposed and applied to both conventionally propelled and solar sail spacecraft operating at an arbitrarily shaped asteroid in the class of Itokawa. As an example, stand-off inertial hovering is considered, recently identified as a challenging part of the Marco Polo mission. The approach is easily extended to stand-off orbits. We show that DMOC is applicable to spacecraft control at small objects, in particular with regard to the fact that the changes in gravity are exploited by the algorithm to optimally control the spacecraft position. Furthermore, we provide some remarks on promising developments.}, language = {en} } @inproceedings{GeibenGoettenHavermann2020, author = {Geiben, Benedikt and G{\"o}tten, Falk and Havermann, Marc}, title = {Aerodynamic analysis of a winged sub-orbital spaceplane}, publisher = {DGLR}, address = {Bonn}, doi = {10.25967/530170}, year = {2020}, abstract = {This paper primarily presents an aerodynamic CFD analysis of a winged spaceplane geometry based on the Japanese Space Walker proposal. StarCCM was used to calculate aerodynamic coefficients for a typical space flight trajectory including super-, trans- and subsonic Mach numbers and two angles of attack. Since the solution of the RANS equations in such supersonic flight regimes is still computationally expensive, inviscid Euler simulations can principally lead to a significant reduction in computational effort. The impact on accuracy of aerodynamic properties is further analysed by comparing both methods for different flight regimes up to a Mach number of 4.}, language = {en} } @article{Gerhardt2005, author = {Gerhardt, Hans Joachim}, title = {Design methods of smoke and heat exhaust systems in construction works}, series = {V Mie\&\#796;dzynarodowa Konferencja Bezpiecze\&\#324;stwo Po\&\#380;arowe Budowli, Warszawa-Miedzeszyn, 14 - 16 listopada 2005 r. = : Vth International Conference Fire Safety of Buildings / ITB ... [Ed. Miros\&\#322;aw Kosiorek]}, journal = {V Mie\&\#796;dzynarodowa Konferencja Bezpiecze\&\#324;stwo Po\&\#380;arowe Budowli, Warszawa-Miedzeszyn, 14 - 16 listopada 2005 r. = : Vth International Conference Fire Safety of Buildings / ITB ... [Ed. Miros\&\#322;aw Kosiorek]}, publisher = {ITB}, address = {Warszawa}, isbn = {83-7413-810-6}, pages = {127 -- 140}, year = {2005}, language = {en} } @article{GerhardtCooperWhitbreadetal.1985, author = {Gerhardt, Hans Joachim and Cooper, K.-R. and Whitbread, R. and Gary, K.-P. (u.a.)}, title = {A comparison of aerodynamic drag measurements on model trucks in closed-jet and open-jet wind tunnels}, pages = {261 -- 274}, year = {1985}, language = {en} } @article{GerhardtKonrathLieb2005, author = {Gerhardt, Hans Joachim and Konrath, B. and Lieb, R.-D.}, title = {Das Drallrohr}, series = {HLH : L{\"u}ftung, Klima, Heizung, Sanit{\"a}r, Geb{\"a}udetechnik. 56 (2005), H. 11}, journal = {HLH : L{\"u}ftung, Klima, Heizung, Sanit{\"a}r, Geb{\"a}udetechnik. 56 (2005), H. 11}, isbn = {1436-5103}, pages = {91 -- 95}, year = {2005}, language = {en} } @article{GerhardtKramer1985, author = {Gerhardt, Hans Joachim and Kramer, C.}, title = {Aerodynamsiche RA-Optimierung}, series = {Zentralblatt fuer Industriebau. 31 (1985), H. 5}, journal = {Zentralblatt fuer Industriebau. 31 (1985), H. 5}, isbn = {0044-4227}, pages = {358 -- 362}, year = {1985}, language = {en} } @article{GerhardtKramerJanssen1985, author = {Gerhardt, Hans Joachim and Kramer, C. and Janssen, L.-J.}, title = {Flow studies of an open jet wind tunnel and comparison with closed and slotted walls}, pages = {7 -- 28}, year = {1985}, language = {en} } @article{GerhardtKrueger1997, author = {Gerhardt, Hans Joachim and Kr{\"u}ger, O.}, title = {Building shape influence on local wind loads}, series = {Proceedings of the 2nd European \& African Conference on Wind Engineering : 2 EACWE, Palazzo Ducale, Genova, Italy, June 22-26, 1997 / ed. by Giovanni Solari. - Vol. 2}, journal = {Proceedings of the 2nd European \& African Conference on Wind Engineering : 2 EACWE, Palazzo Ducale, Genova, Italy, June 22-26, 1997 / ed. by Giovanni Solari. - Vol. 2}, publisher = {Servizi Grafici Editoriali}, address = {Padova}, isbn = {88-86281-19-6}, pages = {XIX, S. 1017 - 1998 : Ill., graph. Darst.}, year = {1997}, language = {en} }