@inproceedings{GellertButenweg2009, author = {Gellert, Christoph and Butenweg, Christoph}, title = {Nichtlinearer Erdbebennachweis von Mauerwerksbauten}, series = {Erdbeben und Mauerwerk : 11. D-A-CH-Tagung 2009 ; [10./11. September 2009 in Z{\"u}rich] / SGEB, Swiss Society for Earthquake Engineering and Structural Dynamics; Schweizerischer Ingenieur- und Architektenverein, Fachgruppe f{\"u}r Br{\"u}ckenbau und Hochbau. [Hrsg. Dazio, Alessandro ...]}, booktitle = {Erdbeben und Mauerwerk : 11. D-A-CH-Tagung 2009 ; [10./11. September 2009 in Z{\"u}rich] / SGEB, Swiss Society for Earthquake Engineering and Structural Dynamics; Schweizerischer Ingenieur- und Architektenverein, Fachgruppe f{\"u}r Br{\"u}ckenbau und Hochbau. [Hrsg. Dazio, Alessandro ...]}, publisher = {SIA}, address = {Z{\"u}rich}, organization = {D-A-C-H Tagung <11, 2009, Z{\"u}rich>}, isbn = {978-3-03732-021-1}, pages = {125 -- 132}, year = {2009}, language = {de} } @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} } @inproceedings{SchartnerLoebDachwaldetal.2009, author = {Schartner, Karl-Heinz and Loeb, H. W. and Dachwald, Bernd and Ohndorf, Andreas}, title = {Perspectives of electric propulsion for outer planetary and deep space missions}, series = {European Planetary Science Congress 2009}, booktitle = {European Planetary Science Congress 2009}, pages = {416 -- 416}, year = {2009}, abstract = {Solar-electric propulsion (SEP) is superior with respect to payload capacity, flight time and flexible launch window to the conventional interplanetary transfer method using chemical propulsion combined with gravity assists. This fact results from the large exhaust velocities of electric low-thrust propulsion and is favourable also for missions to the giant planets, Kuiper-belt objects and even for a heliopause probe (IHP) as shown in three studies by the authors funded by DLR. They dealt with a lander for Europa and a sample return mission from a mainbelt asteroid [1], with the TANDEM mission [2]; the third recent one investigates electric propulsion for the transfer to the edge of the solar system. All studies are based on triple-junction solar arrays, on rf-ion thrusters of the qualified RIT-22 type and they use the intelligent trajectory optimization program InTrance [3].}, language = {en} } @inproceedings{DigelDachwaldArtmannetal.2009, author = {Digel, Ilya and Dachwald, Bernd and Artmann, Gerhard and Linder, Peter and Funke, O.}, title = {A concept of a probe for particle analysis and life detection in icy environments}, year = {2009}, abstract = {A melting probe equipped with autofluorescence-based detection system combined with a light scattering unit, and, optionally, with a microarray chip would be ideally suited to probe icy environments like Europa's ice layer as well as the polar ice layers of Earth and Mars for recent and extinct live.}, subject = {Sonde}, language = {en} } @inproceedings{O'HerasDigelTemizArtmann2009, author = {O\'Heras, Carlos and Digel, Ilya and Temiz Artmann, Ayseg{\"u}l}, title = {Nanostructured carbon-based column for LPS/protein adsorption : [abstract]}, year = {2009}, abstract = {The absence of a general method for endotoxin removal from liquid interfaces gives an opportunity to find new methods and materials to overcome this gap. Activated nanostructured carbon is a promising material that showed good adsorption properties due to its vast pore network and high surface area. The aim of this study is to find the adsorption rates for a carboneous material produced at different temperatures, as well as to reveal possible differences between the performance of the material for each of the adsorbates used during the study (hemoglobin, serum albumin and lipopolysaccharide, LPS).}, subject = {Kohlenstofffaser}, language = {en} } @inproceedings{ElBashirDigel2009, author = {ElBashir, Rasha and Digel, Ilya}, title = {Effect of nitric oxide gas on hydrogels : [abstract]}, year = {2009}, abstract = {The results support our theory that the NO gas has an influence in increasing the translational diffusion of hydrogels and it accelerates the melting process of the gels.}, subject = {Stickstoffmonoxid}, language = {en} } @inproceedings{BassamDigelArtmann2009, author = {Bassam, Rasha and Digel, Ilya and Artmann, Gerhard}, title = {Effect of nitric oxide on protein thermal stability : [abstract]}, year = {2009}, abstract = {As a deduction from these results, we can conclude that proteins mainly in vitro, denaturate totally at a temperature between 57°C -62°C, and they also affected by NO and different ions types. In which mainly, NO cause earlier protein denaturation, which means that, NO has a destabilizing effect on proteins, and also different ions will alter the protein denaturation in which, some ions will cause earlier protein denaturation while others not.}, subject = {Stickstoffmonoxid}, 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{Bung2009, author = {Bung, Daniel Bernhard}, title = {Optimierung des potentiellen Sauerstoffeintrags auf Treppenschussrinnen mit gem{\"a}ßigter Neigung}, series = {9. JuWi-Treffen : Beitr{\"a}ge zum Treffen junger Wissenschaftlerinnen und junger Wissenschaftler deutschsprachiger Wasserbauinstitute}, booktitle = {9. JuWi-Treffen : Beitr{\"a}ge zum Treffen junger Wissenschaftlerinnen und junger Wissenschaftler deutschsprachiger Wasserbauinstitute}, editor = {Theobald, S.}, publisher = {Universit{\"a}t Kassel}, address = {Kassel}, pages = {73 -- 78}, year = {2009}, language = {de} } @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} } @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{GoemmelKobNiendorfetal.2009, author = {G{\"o}mmel, Andreas and Kob, Malte and Niendorf, Thoralf and Butenweg, Christoph}, title = {An approach for numerical calculation of glottal flow during glottal closure}, series = {Proceedings / NAG/DAGA 2009, International Conference on Acoustics : Rotterdam, 23 - 26 March 2009 ; [including the 35th German Annual Conference on Acoustics (DAGA)] / [organisers: Acoustical Society of the Netherlands (NAG); German Acoustical Society (DEGA) ...]. Ed. by Marinus M. Boone}, booktitle = {Proceedings / NAG/DAGA 2009, International Conference on Acoustics : Rotterdam, 23 - 26 March 2009 ; [including the 35th German Annual Conference on Acoustics (DAGA)] / [organisers: Acoustical Society of the Netherlands (NAG); German Acoustical Society (DEGA) ...]. Ed. by Marinus M. Boone}, publisher = {DEGA}, address = {Berlin}, organization = {NAG DAGA <2009, Rotterdam>}, isbn = {978-3-9808659-6-8}, pages = {1722 -- 1725}, year = {2009}, language = {en} } @inproceedings{ArinkinDigel2009, author = {Arinkin, Vladimir and Digel, Ilya}, title = {Water bridge phenomenon : [abstract]}, year = {2009}, abstract = {One of interesting but not well known water properties is related to appearance of highly ordered structures in response to strong electrical field. In 1893 Sir William Armstrong placed a cotton thread between two wine glasses filled with chemically pure water. When high DC voltage was applied between the glasses, a connection consisting of water formed, producing a "water bridge"}, subject = {Hydrodynamik}, language = {en} } @inproceedings{MeskourisHollerButenwegetal.2009, author = {Meskouris, Konstantin and Holler, Stefan and Butenweg, Christoph and Meiners, Daniel}, title = {A multiphase model with hypoplastic formulation of the solid phase and its application to earthquake engineering problems}, series = {Computational structural dynamics and earthquake engineering / ed. by Manolis Papadrakakis .... (Structures and infrastructures series ; 2)}, booktitle = {Computational structural dynamics and earthquake engineering / ed. by Manolis Papadrakakis .... (Structures and infrastructures series ; 2)}, publisher = {CRC Press}, address = {Boca Raton, Fla. [u.a.]}, isbn = {978-0-415-45261-8}, doi = {10.1201/9780203881637.ch19}, pages = {293 -- 308}, year = {2009}, language = {en} } @inproceedings{SpurmannOhndorfDachwaldetal.2009, author = {Spurmann, J{\"o}rn and Ohndorf, Andreas and Dachwald, Bernd and Seboldt, Wolfgang and L{\"o}b, Horst and Schartner, Karl-Heinz}, title = {Interplanetary trajectory optimization for a sep mission to Saturn}, series = {60th International Astronautical Congress 2009}, booktitle = {60th International Astronautical Congress 2009}, isbn = {9781615679089}, pages = {5234 -- 5248}, year = {2009}, abstract = {The recently proposed NASA and ESA missions to Saturn and Jupiter pose difficult tasks to mission designers because chemical propulsion scenarios are not capable of transferring heavy spacecraft into the outer solar system without the use of gravity assists. Thus our developed mission scenario based on the joint NASA/ESA Titan Saturn System Mission baselines solar electric propulsion to improve mission flexibility and transfer time. For the calculation of near-globally optimal low-thrust trajectories, we have used a method called Evolutionary Neurocontrol, which is implemented in the low-thrust trajectory optimization software InTrance. The studied solar electric propulsion scenario covers trajectory optimization of the interplanetary transfer including variations of the spacecraft's thrust level, the thrust unit's specific impulse and the solar power generator power level. Additionally developed software extensions enabled trajectory optimization with launcher-provided hyperbolic excess energy, a complex solar power generator model and a variable specific impulse ion engine model. For the investigated mission scenario, Evolutionary Neurocontrol yields good optimization results, which also hold valid for the more elaborate spacecraft models. Compared to Cassini/Huygens, the best found solutions have faster transfer times and a higher mission flexibility in general.}, language = {en} } @inproceedings{GoettscheSchwarzerRoetheretal.2009, author = {G{\"o}ttsche, Joachim and Schwarzer, Klemens and R{\"o}ther, Sascha and Jellinghaus, Sabine and Helten, G. and Wittmann, R.}, title = {Efficient daylighting, heating and shading with rooflight heliostats}, series = {Renewables in a changing climate : from Nano to Urban Scale : CISBAT 2009 : 2-3 September 2009, EPFL, Lausanne, Switzerland : proceedings}, booktitle = {Renewables in a changing climate : from Nano to Urban Scale : CISBAT 2009 : 2-3 September 2009, EPFL, Lausanne, Switzerland : proceedings}, publisher = {Ecole Polytechnique F{\´e}d{\´e}rale de Lausanne}, address = {Lausanne}, pages = {243 -- 246}, year = {2009}, language = {en} }