@inproceedings{DrummSchmittDoetal.2007, author = {Drumm, Christian and Schmitt, Matthias and Do, Hong-Hai and Rahm, Erhard}, title = {Quickmig: automatic schema matching for data migration projects}, series = {Proceedings of the 2007 ACM Conference on Information and Knowledge Management / CIKM'07, Lisboa, Portugal, Nov. 6 - 10, 2007}, booktitle = {Proceedings of the 2007 ACM Conference on Information and Knowledge Management / CIKM'07, Lisboa, Portugal, Nov. 6 - 10, 2007}, isbn = {978-1-59593-803-9}, doi = {10.1145/1321440.1321458}, pages = {107 -- 116}, year = {2007}, language = {en} } @inproceedings{WeberMarkovicDrumm2007, author = {Weber, Ingo and Markovic, Ivan and Drumm, Christian}, title = {A conceptual framework for composition in business process management}, series = {Business Information Systems : 10th International Conference, BIS 2007, Poznan, Poland, April 25-27, 2007. Proceedings}, booktitle = {Business Information Systems : 10th International Conference, BIS 2007, Poznan, Poland, April 25-27, 2007. Proceedings}, publisher = {Springer}, address = {Berlin, Heidelberg}, isbn = {978-3-540-72035-5}, doi = {10.1007/978-3-540-72035-5_5}, pages = {54 -- 66}, 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} } @phdthesis{Trzewik2007, author = {Trzewik, J{\"u}rgen}, title = {Experimental analysis of biaxial mechanical tension in cell monolayers and cultured three-dimensional tissues: the celldrum technology}, publisher = {Univerist{\"a}tsverlg Ilmenau}, address = {Ilmenau}, year = {2007}, language = {en} } @article{WallerBraunHojdisetal.2007, author = {Waller, Mark P. and Braun, Heiko and Hojdis, Nils and B{\"u}hl, Michael}, title = {Geometries of Second-Row Transition-Metal Complexes from Density-Functional Theory}, series = {Journal of Chemical Theory and Computation}, volume = {3}, journal = {Journal of Chemical Theory and Computation}, number = {6}, issn = {1549-9626}, doi = {10.1021/ct700178y}, pages = {2234 -- 2242}, year = {2007}, language = {en} } @article{KrollLudwigs2007, author = {Kroll-Ludwigs, Kathrin}, title = {The Reform of German Maintenance Law}, series = {The International Survey of Family Law}, journal = {The International Survey of Family Law}, pages = {85 -- 100}, year = {2007}, language = {en} } @inproceedings{WeissAbanteribaEsch2007, author = {Weiss, Alexander and Abanteriba, Sylvester and Esch, Thomas}, title = {Investigation of Flow Separation Inside a Conical Rocket Nozzle With the Aid of an Annular Cross Flow}, series = {Proceedings of the ASME/JSME 2007 5th Joint Fluids Engineering Conference. Volume 1: Symposia, Parts A and B}, booktitle = {Proceedings of the ASME/JSME 2007 5th Joint Fluids Engineering Conference. Volume 1: Symposia, Parts A and B}, publisher = {American Society of Mechanical Engineers (ASME)}, address = {New York}, isbn = {0-7918-4288-6}, doi = {10.1115/FEDSM2007-37387}, pages = {1861 -- 1871}, year = {2007}, abstract = {Flow separation is a phenomenon that occurs in all kinds of supersonic nozzles sometimes during run-up and shut-down operations. Especially in expansion nozzles of rocket engines with large area ratio, flow separation can trigger strong side loads that can damage the structure of the nozzle. The investigation presented in this paper seeks to establish measures that may be applied to alter the point of flow separation. In order to achieve this, a supersonic nozzle was placed at the exit plane of the conical nozzle. This resulted in the generation of cross flow surrounding the core jet flow from the conical nozzle. Due to the entrainment of the gas stream from the conical nozzle the pressure in its exit plane was found to be lower than that of the ambient. A Cold gas instead of hot combustion gases was used as the working fluid. A mathematical simulation of the concept was validated by experiment. Measurements confirmed the simulation results that due to the introduction of a second nozzle the pressure in the separated region of the conical nozzle was significantly reduced. It was also established that the boundary layer separation inside the conical nozzle was delayed thus allowing an increased degree of overexpansion. The condition established by the pressure measurements was also demonstrated qualitatively using transparent nozzle configurations.}, language = {en} } @incollection{ReimerBraunBallmann2007, author = {Reimer, Lars and Braun, Carsten and Ballmann, Josef}, title = {Computational study of the aeroelastic equilibrium configuration of a swept wind tunnel wing model in subsonic flow}, series = {High performance computing in science and engineering '06. Transactions of the High Performance Computing Center Stuttgart (HLRS) 2006 / Wolfgang E. Nagel ... Eds.}, booktitle = {High performance computing in science and engineering '06. Transactions of the High Performance Computing Center Stuttgart (HLRS) 2006 / Wolfgang E. Nagel ... Eds.}, publisher = {Springer}, address = {Berlin [u.a.]}, isbn = {978-3-540-36165-7}, pages = {421 -- 434}, year = {2007}, abstract = {In the Collaborative Research Center SFB 401 at RWTH Aachen University, the numerical aeroelastic method SOFIA for direct numerical aeroelastic simulation is being progressively developed. Numerical results obtained by applying SOFIA were compared with measured data of static and dynamic aeroelastic wind tunnel tests for an elastic swept wing in subsonic flow.}, language = {en} } @article{MistlerAnthoineButenweg2007, author = {Mistler, Michael and Anthoine, A. and Butenweg, Christoph}, title = {In-plane and out-of-plane homogenisation of masonry}, series = {Computers \& structures}, volume = {Volume 85}, journal = {Computers \& structures}, number = {Issues 17-18}, issn = {1879-2243 (E-Journal); 0045-7949 (Print)}, doi = {10.1016/j.compstruc.2006.08.087}, pages = {1321 -- 1330}, 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} } @article{GoemmelButenwegBolenderetal.2007, author = {G{\"o}mmel, Andreas and Butenweg, Christoph and Bolender, Katrin and Grunendahl, Arno}, title = {A muscle controlled finite-element model of laryngeal abduction and adduction}, series = {Computer methods in biomechanics and biomedical engineering}, volume = {Volume 10}, journal = {Computer methods in biomechanics and biomedical engineering}, number = {Issue 5}, issn = {1476-8259 (E-Journal); 1025-5842 (Print)}, pages = {377 -- 388}, year = {2007}, language = {en} } @incollection{MeskourisButenwegKalkeretal.2007, author = {Meskouris, Konstantin and Butenweg, Christoph and Kalker, Ines and Mistler, Michael}, title = {Numerical simulation of historic masonry buildings}, series = {Antike Erdbeben im alpinen und zirkumalpinen Raum : Befunde und Probleme in arch{\"a}ologischer, historischer und seismologischer Sicht ; Beitr{\"a}ge des Interdisziplin{\"a}ren Workshops Schloss Hohenkammer, 14./15. Mai 2004 = Earthquakes in antiquity in the alpine and circum-alpine region / Gerhard H. Waldherr ; Anselm Smolka (Hrsg.) (Geographica Historica ; 24)}, booktitle = {Antike Erdbeben im alpinen und zirkumalpinen Raum : Befunde und Probleme in arch{\"a}ologischer, historischer und seismologischer Sicht ; Beitr{\"a}ge des Interdisziplin{\"a}ren Workshops Schloss Hohenkammer, 14./15. Mai 2004 = Earthquakes in antiquity in the alpine and circum-alpine region / Gerhard H. Waldherr ; Anselm Smolka (Hrsg.) (Geographica Historica ; 24)}, publisher = {Franz Steiner Verlag}, address = {Stuttgart}, isbn = {978-3-515-09030-8 ; 3-515-09030-4}, pages = {171 -- 189}, year = {2007}, language = {en} } @article{ZerlinDigelStadleretal.2007, author = {Zerlin, Kay and Digel, Ilya and Stadler, Andreas M. and B{\"u}ldt, Georg and Zaccai, Guiseppe and Artmann, Gerhard}, title = {Dynamics and interactions of hemoglobin in human red blood cells and concentrated hemoglobin solutions}, series = {Regenerative medicine. 2 (2007), H. 5}, journal = {Regenerative medicine. 2 (2007), H. 5}, isbn = {1746-0751}, pages = {573 -- 573}, year = {2007}, language = {en} } @article{ArtmannZerlinDigeletal.2007, author = {Artmann, Gerhard and Zerlin, Kay and Digel, Ilya and Stadler, Andreas M.}, title = {Physical discontinuities at body temperature in human red blood cells / Artmann, GM ; Zerlin, K ; Digel, I ; Stadler, A ; Zaccai, G ; Temiz, AA}, series = {Tissue Engineering. 13 (2007), H. 7}, journal = {Tissue Engineering. 13 (2007), H. 7}, isbn = {1076-3279}, pages = {1778 -- 1778}, 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} } @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} } @inproceedings{Dachwald2007, author = {Dachwald, Bernd}, title = {Low-Thrust Mission Analysis and Global Trajectory Optimization Using Evolutionary Neurocontrol: New Results}, series = {European Workshop on Space Mission Analysis ESA/ESOC, Darmstadt, Germany 10 { 12 Dec 2007}, booktitle = {European Workshop on Space Mission Analysis ESA/ESOC, Darmstadt, Germany 10 { 12 Dec 2007}, year = {2007}, abstract = {Interplanetary trajectories for low-thrust spacecraft are often characterized by multiple revolutions around the sun. Unfortunately, the convergence of traditional trajectory optimizers that are based on numerical optimal control methods depends strongly on an adequate initial guess for the control function (if a direct method is used) or for the starting values of the adjoint vector (if an indirect method is used). Especially when many revolutions around the sun are re- quired, trajectory optimization becomes a very difficult and time-consuming task that involves a lot of experience and expert knowledge in astrodynamics and optimal control theory, because an adequate initial guess is extremely hard to find. Evolutionary neurocontrol (ENC) was proposed as a smart method for low-thrust trajectory optimization that fuses artificial neural networks and evolutionary algorithms to so-called evolutionary neurocontrollers (ENCs) [1]. Inspired by natural archetypes, ENC attacks the trajectoryoptimization problem from the perspective of artificial intelligence and machine learning, a perspective that is quite different from that of optimal control theory. Within the context of ENC, a trajectory is regarded as the result of a spacecraft steering strategy that maps permanently the actual spacecraft state and the actual target state onto the actual spacecraft control vector. This way, the problem of searching the optimal spacecraft trajectory is equivalent to the problem of searching (or "learning") the optimal spacecraft steering strategy. An artificial neural network is used to implement such a spacecraft steering strategy. It can be regarded as a parameterized function (the network function) that is defined by the internal network parameters. Therefore, each distinct set of network parameters defines a different network function and thus a different steering strategy. The problem of searching the optimal steering strategy is now equivalent to the problem of searching the optimal set of network parameters. Evolutionary algorithms that work on a population of (artificial) chromosomes are used to find the optimal network parameters, because the parameters can be easily mapped onto a chromosome. The trajectory optimization problem is solved when the optimal chromosome is found. A comparison of solar sail trajectories that have been published by others [2, 3, 4, 5] with ENC-trajectories has shown that ENCs can be successfully applied for near-globally optimal spacecraft control [1, 6] and that they are able to find trajectories that are closer to the (unknown) global optimum, because they explore the trajectory search space more exhaustively than a human expert can do. The obtained trajectories are fairly accurate with respect to the terminal constraint. If a more accurate trajectory is required, the ENC-solution can be used as an initial guess for a local trajectory optimization method. Using ENC, low-thrust trajectories can be optimized without an initial guess and without expert attendance. Here, new results for nuclear electric spacecraft and for solar sail spacecraft are presented and it will be shown that ENCs find very good trajectories even for very difficult problems. Trajectory optimization results are presented for 1. NASA's Solar Polar Imager Mission, a mission to attain a highly inclined close solar orbit with a solar sail [7] 2. a mission to de ect asteroid Apophis with a solar sail from a retrograde orbit with a very-high velocity impact [8, 9] 3. JPL's \2nd Global Trajectory Optimization Competition", a grand tour to visit four asteroids from different classes with a NEP spacecraft}, language = {en} } @article{GoeddekeStrzodkaMohdYusofetal.2007, author = {G{\"o}ddeke, Dominik and Strzodka, Robert and Mohd-Yusof, Jamaludin and McCormick, Patrick and Buijssen, Sven H.M. and Grajewski, Matthias and Turek, Stefan}, title = {Exploring weak scalability for FEM calculations on a GPU-enhanced cluster}, series = {Parallel Computing}, volume = {33}, journal = {Parallel Computing}, number = {10-11}, issn = {0167-8191}, doi = {10.1016/j.parco.2007.09.002}, pages = {685 -- 699}, year = {2007}, language = {en} } @article{HeuermannErkens2007, author = {Heuermann, Holger and Erkens, H.}, title = {Mixed-Mode Chain Scattering Parameters: Theory and Verification}, series = {IEEE Transactions on Microwave Theory and Techniques}, volume = {55}, journal = {IEEE Transactions on Microwave Theory and Techniques}, number = {8}, publisher = {IEEE}, address = {New York}, isbn = {0018-9480}, doi = {10.1109/TMTT.2007.902587}, pages = {1704 -- 1708}, year = {2007}, abstract = {Chain scattering parameters or T-parameters are a useful tool for calculating cascaded two-ports. With the increasing importance of mixed-mode S-parameters, a need for converting the T-parameters from their unbalanced form into a balanced form emerges for suiting both common and differential mode waves, as well as the mode conversion. This paper presents the derivation of the equations for transformations between mixed-mode S- and T-parameters for a mixed-mode two-port. Although derived in a way very similar to monomode T-parameters, no simplifications were necessary. Measurement results exemplify the quality of the T-parameter transformation under real-life conditions.}, language = {en} } @article{PoghossianIngebrandtAbouzaretal.2007, author = {Poghossian, Arshak and Ingebrandt, S. and Abouzar, Maryam H. and Sch{\"o}ning, Michael Josef}, title = {Label-free detection of charged macromolecules by using a field-effect-based sensor platform: Experiments and possible mechanisms of signal generation}, series = {Applied Physics A: Materials Science \& Processing. 87 (2007), H. 3}, journal = {Applied Physics A: Materials Science \& Processing. 87 (2007), H. 3}, isbn = {0947-8396}, pages = {517 -- 524}, year = {2007}, language = {en} }