@article{DachwaldCarnelliVasile2007, author = {Dachwald, Bernd and Carnelli, I. and Vasile, M.}, title = {Optimizing low-thrust gravity assist interplanetary trajectories using evolutionary neurocontrollers / I. Carnelli ; B. Dachwald ; M. Vasile}, series = {IEEE Congress on Evolutionary Computation, 2007 : CEC 2007 ; 25 - 28 September 2007, Singapore}, journal = {IEEE Congress on Evolutionary Computation, 2007 : CEC 2007 ; 25 - 28 September 2007, Singapore}, publisher = {IEEE Service Center}, address = {Piscataway, NJ}, isbn = {978-1-424-41339-3}, pages = {965 -- 972}, year = {2007}, language = {en} } @inproceedings{DachwaldKahleWie2007, author = {Dachwald, Bernd and Kahle, Ralph and Wie, Bong}, title = {Head-on impact deflection of NEAs: a case study for 99942 Apophis}, series = {Planetary Defense Conference 2007}, booktitle = {Planetary Defense Conference 2007}, pages = {1 -- 12}, year = {2007}, abstract = {Near-Earth asteroid (NEA) 99942 Apophis provides a typical example for the evolution of asteroid orbits that lead to Earth-impacts after a close Earth-encounter that results in a resonant return. Apophis will have a close Earth-encounter in 2029 with potential very close subsequent Earth-encounters (or even an impact) in 2036 or later, depending on whether it passes through one of several less than 1 km-sized gravitational keyholes during its 2029-encounter. A pre-2029 kinetic impact is a very favorable option to nudge the asteroid out of a keyhole. The highest impact velocity and thus deflection can be achieved from a trajectory that is retrograde to Apophis orbit. With a chemical or electric propulsion system, however, many gravity assists and thus a long time is required to achieve this. We show in this paper that the solar sail might be the better propulsion system for such a mission: a solar sail Kinetic Energy Impactor (KEI) spacecraft could impact Apophis from a retrograde trajectory with a very high relative velocity (75-80 km/s) during one of its perihelion passages. The spacecraft consists of a 160 m × 160 m, 168 kg solar sail assembly and a 150 kg impactor. Although conventional spacecraft can also achieve the required minimum deflection of 1 km for this approx. 320 m-sized object from a prograde trajectory, our solar sail KEI concept also allows the deflection of larger objects. For a launch in 2020, we also show that, even after Apophis has flown through one of the gravitational keyholes in 2029, the solar sail KEI concept is still feasible to prevent Apophis from impacting the Earth, but many KEIs would be required for consecutive impacts to increase the total Earth-miss distance to a safe value}, language = {en} } @article{DachwaldMacDonaldMcInnes2007, author = {Dachwald, Bernd and MacDonald, Malcolm and McInnes, Colin R.}, title = {Heliocentric Solar Sail Orbit Transfers with Locally Optimal Control Laws / Malcolm Macdonald ; Colin McInnes ; Bernd Dachwald}, series = {Journal of Spacecraft and Rockets. 44 (2007), H. 1}, journal = {Journal of Spacecraft and Rockets. 44 (2007), H. 1}, isbn = {0022-4650}, pages = {273 -- 276}, year = {2007}, language = {en} } @article{DachwaldMcDonaldMcInnesetal.2007, author = {Dachwald, Bernd and McDonald, Malcolm and McInnes, Colin R. and Mengali, Giovanni}, title = {Impact of Optical Degradation on Solar Sail Mission Performance}, series = {Journal of Spacecraft and Rockets. 44 (2007), H. 4}, journal = {Journal of Spacecraft and Rockets. 44 (2007), H. 4}, isbn = {0022-4650}, pages = {740 -- 749}, year = {2007}, language = {en} } @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} } @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} } @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{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} } @book{Damrau2007, author = {Damrau, Karin}, title = {Stadtspiele : 2 St{\"a}dte, 5 Spielst{\"a}tten ; eine spielerische Auseinandersetzung mit den Qualit{\"a}ten des {\"o}ffentlichen Raumes ; die Arbeiten entstanden w{\"a}hrend des Aufenthalts an der Akademie Schloss Solitude, Stuttgart 2006 = Urban games / Karin Damrau. [Hrsg.: Akademie Schloss Solitude]}, publisher = {Akademie Schloss Solitude}, address = {Solitude}, isbn = {9783937158242}, pages = {34 S. : zahlr. Ill}, year = {2007}, language = {de} } @article{DanielStarck2007, author = {Daniel, Bernd and Starck, Andreas}, title = {Die Anwendung der VOB in der baubetrieblichen Praxis}, year = {2007}, abstract = {Eine Einf{\"u}hrung in die Anwendung der VOB in der baubetrieblichen Praxis im Rahmen der erg{\"a}nzenden Schriften zu den Vorlesungen. Die Anwendung der VOB als Vertragsbedingung f{\"u}r einen Bauvertrag ist g{\"a}ngige Praxis, {\"u}ber die der Architekt im Baubetrieb umfassend informiert sein muß. Die Anwendung der VOB im Bauvertrag bedarf der vorherigen Vereinbarung zwischen den Vertragsparteien. Dabei muß die VOB im Ganzen vereinbart werden. Eine Ver{\"a}nderung dieser Bestimmungen f{\"u}hrt zur teilweisen Unwirksamkeit der vertraglichen Vereinbarung. Der Architekt, der f{\"u}r seinen Bauherrn die Vergabeunterlagen zusammenstellen muß, haftet f{\"u}r Fehler bei der Formulierung oder der Zusammenstellung. Es ist daher f{\"u}r den Architekten unerl{\"a}ßlich, die vertraglichen Zusammenh{\"a}nge zu kennen. Dieser Fachaufsatz soll zu einem sicheren Umgang mit der VOB als Vertragsgrundlage beitragen.}, subject = {Baubetrieb}, language = {de} } @article{DanielStarck2007, author = {Daniel, Bernd and Starck, Andreas}, title = {Kostenkontrolle und Kostensteuerung im Hochbau}, year = {2007}, abstract = {Textauszug: Nach dem Leistungsbild der HOAI hat der Architekt bei Planung und Baubetrieb vier Stationen der Kostenermittlung entsprechend der DIN 276, Abschnitt 2.3 abzuarbeiten. Der Architekt, der seiner Verantwortung gerecht werden will, wird hier weitere Kontrollmechanismen einbauen wollen. {\"U}ber die genannten Kostenermittlungen hinaus kennt die DIN 276 daher noch das Erfordernis der Kostenkontrolle in Abschnitt 2.4 und der Kostensteuerung in Abschnitt 2.5. Die Kostensteuerung greift immer dann, wenn die Kostenkontrolle eine Abweichung des Kostenrahmens von den Sollwerten aufzeigt. Dazu m{\"u}ssen die Kontrollinstanzen dort eingebaut werden, wo Korrekturen noch m{\"o}glich sind. Eine erste Kontrolle der Kosten ist daher zwischen Massenermittlung und Vergabe sinnvoll einzuflechten. Zu diesem Zeitpunkt kann die Planung noch ver{\"a}ndert werden, was einen ersten steuernden Eingriff in die Baukosten erm{\"o}glicht, und zwar bevor die Angebotsunterlagen verschickt werden. Die Grundlagen zu einer effektiven Kostensteuerung werden in der Mengenermittlung der Leistungsphase 6 gelegt. Wenn dort die Mengen nicht sorgf{\"a}ltig und nachvollziehbar ermittelt wurden, wird der Soll- Ist- Abgleich w{\"a}hrend der Bauphase nicht fr{\"u}hzeitig genug gelingen, wenn nicht gar ganz entfallen. Es gilt also, daf{\"u}r zu sorgen, dass die Mengenermittlung zur Vergabe mit entsprechender Sorgfalt und vor Allem „projektnah" erfolgt. Sch{\"a}tzungen haben hier keine Berechtigung.}, subject = {Projektsteuerung}, language = {de} } @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} } @article{DielmannBockSonnek2007, author = {Dielmann, Klaus-Peter and Bock, Alexis and Sonnek, Frederic}, title = {Stand der CO2-Allokationspl{\"a}ne in Europa und Durchsetzung der Monitoring-Richtlinien}, series = {VGB PowerTech : international journal for electricity and heat generation}, volume = {87}, journal = {VGB PowerTech : international journal for electricity and heat generation}, number = {3}, isbn = {1435-3199}, pages = {40 -- 46}, year = {2007}, language = {de} } @article{DigelKurulganDemirciLinderetal.2007, author = {Digel, Ilya and Kurulgan Demirci, Eylem and Linder, Peter and Kayser, Peter}, title = {Decrease in extracellular collagen crosslinking after NMR magnetic field application in skin fibroblasts}, series = {Medical and Biological Engineering and Computing. 45 (2007), H. 1}, journal = {Medical and Biological Engineering and Computing. 45 (2007), H. 1}, isbn = {1741-0444}, pages = {91 -- 97}, year = {2007}, language = {en} } @article{DigelZerlinTemizArtmannetal.2007, author = {Digel, Ilya and Zerlin, Kay and Temiz Artmann, Ayseg{\"u}l and Engels, S.}, title = {Protein dynamics in thermosensation}, series = {Regenerative medicine. 2 (2007), H. 5}, journal = {Regenerative medicine. 2 (2007), H. 5}, isbn = {1746-0751}, pages = {533 -- 533}, year = {2007}, language = {en} } @inproceedings{DiltheySchleserChudobaetal.2007, author = {Dilthey, Ulrich and Schleser, Markus and Chudoba, Rostislav and Konrad, Martin}, title = {Experimental investigation and micro-mechanical simulaltion of concrete reinforced with epoxy impregnated fabrics}, series = {Fibre-reinforced polymer reinforcement for concrete structures : proceedings of the 8th international conference : Patras, Greece, July 16- 18, 2007}, booktitle = {Fibre-reinforced polymer reinforcement for concrete structures : proceedings of the 8th international conference : Patras, Greece, July 16- 18, 2007}, editor = {Triantafillou, T. C.}, publisher = {Univ.}, address = {Patras}, organization = {International Symposium on Fibre-Reinforced Polymer Reinforcement for Concrete Structures <8, 2007, Patras>}, isbn = {9608969107}, pages = {456 -- 457}, year = {2007}, language = {en} } @inproceedings{DiltheySchleserHeggeretal.2007, author = {Dilthey, Ulrich and Schleser, Markus and Hegger, Josef and Voss, Stefan}, title = {Load-bearing behaviour of polymer-impregnated textiles in concrete}, series = {Fifth International Workshop on High Performance Fiber Reinforced Cement Composites (HPFRCC 5) : Mainz, July 10 - 13, 2007. (RILEM proceedings. 53)}, booktitle = {Fifth International Workshop on High Performance Fiber Reinforced Cement Composites (HPFRCC 5) : Mainz, July 10 - 13, 2007. (RILEM proceedings. 53)}, editor = {Reinhardt, Hans W.}, publisher = {RILEM Publ.}, address = {Bagneux}, organization = {International Workshop on High Performance Fiber Reinforced Cement Composites <5, 2007, Mainz>}, isbn = {978-2-35158-046-2}, pages = {183 -- 192}, year = {2007}, language = {en} } @inproceedings{DiltheySchleserPuterman2007, author = {Dilthey, Ulrich and Schleser, Markus and Puterman, Moshe}, title = {Investigation and improvement of concrete reinforced with epoxy impregnated fabrics}, series = {Proceedings / 12th International Congress Polymers in Concrete, ICPIC 07, chuncheon, Korea, Sept. 26. - 28., 2007}, booktitle = {Proceedings / 12th International Congress Polymers in Concrete, ICPIC 07, chuncheon, Korea, Sept. 26. - 28., 2007}, publisher = {Kangwoon National Univ.}, address = {Chancheon}, isbn = {978-89-9600450-9}, pages = {725 -- 733}, year = {2007}, language = {en} } @incollection{DrummLemckeOberle2007, author = {Drumm, Christian and Lemcke, Jens and Oberle, Daniel}, title = {Business Process Management And Semantic Technologies}, series = {The Semantic Web}, booktitle = {The Semantic Web}, publisher = {Springer}, address = {Boston, MA}, isbn = {978-0-387-48531-7}, doi = {10.1007/978-0-387-48531-7_10}, pages = {207 -- 239}, year = {2007}, language = {en} }