@article{SpaeteFaberSchwarzeretal.2004,
  author    = {Sp{\"a}te, Frank and Faber, Christian and Schwarzer, Klemens and Hartz, Thomas},
  title     = {Comparison of solar hot water systems in solar settlements - decentralized or centralized systems?},
  series = {Proceedings / organised by: ISES Europe ... [Ed.: Deutsche Gesellschaft f{\"u}r Sonnenenergie e.V. - DGS, Munich ; PSE GmbH - Forschung Entwicklung Marketing, Freiburg]. - Vol. 1},
  journal   = {Proceedings / organised by: ISES Europe ... [Ed.: Deutsche Gesellschaft f{\"u}r Sonnenenergie e.V. - DGS, Munich ; PSE GmbH - Forschung Entwicklung Marketing, Freiburg]. - Vol. 1},
  publisher = {PSE},
  address   = {Freiburg [Breisgau]},
  isbn      = {3-9809656-1-9},
  pages     = {1-666-1-671},
  year      = {2004},
  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}
}
@misc{SponagelWachowitz1992,
  author    = {Sponagel, Stefan and Wachowitz, Waldemar},
  title     = {Shaft seal : United States Patent 5,143,385 ; date of patent: Sep. 1, 1992 / assignee: Firma Carl Freudenberg},
  publisher = {[United States Patent and Trademark Office]},
  address   = {[Alexandria, VA]},
  pages     = {5 S. : Ill.},
  year      = {1992},
  language  = {en}
}
@article{SponagelKilthauSpies1987,
  author    = {Sponagel, Stefan and Kilthau, G. and Spies, K. H.},
  title     = {Sealing mechanism of lip seals},
  series = {Eleventh 11th International Conference on Fluid Sealing : proceedings of the 11th Internat. Conference on Fluid Sealing, held at Cannes, France 8 - 10 April, 1987 / organised and sponsored by BHRA, the Fluid Engineering Centre. Ed. B. S. Nau},
  journal   = {Eleventh 11th International Conference on Fluid Sealing : proceedings of the 11th Internat. Conference on Fluid Sealing, held at Cannes, France 8 - 10 April, 1987 / organised and sponsored by BHRA, the Fluid Engineering Centre. Ed. B. S. Nau},
  publisher = {Elsevier},
  address   = {London},
  isbn      = {3-540-51383-3},
  pages     = {748 -- 772},
  year      = {1987},
  language  = {en}
}
@misc{SponagelGrafGross1989,
  author    = {Sponagel, Stefan and Graf, G{\"u}nter and Groß, Heinz},
  title     = {Method for manufacturing a sealing ring : United States Patent 4,861,536 ; date of patent: Aug. 12, 1989 / assignee: Firma Carl Freudenberg. Inventors: Gunter Graf ; Heinz Gross ; Stefan Sponagel},
  publisher = {[United States Patent and Trademark Office]},
  address   = {[Alexandria, VA]},
  pages     = {5 S. : Ill.},
  year      = {1989},
  language  = {en}
}
@misc{SponagelGrafGross1989,
  author    = {Sponagel, Stefan and Graf, G{\"u}nter and Groß, Heinz},
  title     = {Method for the manufacture of a sealing ring with a sealing lip having hydrodynamically acting return elements : United States Patent 4,850,097 ; date of patent: Jul. 25, 1989 / assignee: Firma Carl Freudenberg. Inventors: Gunter Graf ; Heinz Gross ; Stefan Sponagel},
  publisher = {[United States Patent and Trademark Office]},
  address   = {[Alexandria, VA]},
  pages     = {4 S. : Ill.},
  year      = {1989},
  language  = {en}
}
@article{SponagelBaroudSteffenetal.2002,
  author    = {Sponagel, Stefan and Baroud, G. and Steffen, T. and Wu, J.},
  title     = {Parameter identification for cement infiltration of osteoporotic bone},
  series = {Poromechanics II : Proceedings of the Second Biot Conference on Poromechanics Grenoble, France 26 - 28 August 2002 / ed. by J.-L. Auriault ...},
  journal   = {Poromechanics II : Proceedings of the Second Biot Conference on Poromechanics Grenoble, France 26 - 28 August 2002 / ed. by J.-L. Auriault ...},
  publisher = {Balkema},
  address   = {Lisse [u.a.]},
  isbn      = {90-5809-394-8},
  pages     = {55 -- 58},
  year      = {2002},
  language  = {en}
}
@article{SponagelBaroudFalketal.2004,
  author    = {Sponagel, Stefan and Baroud, G. and Falk, R. and Crookshank, M.},
  title     = {Experimental and theoretical investigation of directional permeability of human vertebral cancellous bone for cement infiltration. G. Baroud, R. Falk, M. Crookshank, S. Sponagel, T. Steffen},
  series = {Journal of Biomechanics. 37 (2004), H. 2},
  journal   = {Journal of Biomechanics. 37 (2004), H. 2},
  isbn      = {0021-9290},
  pages     = {189 -- 196},
  year      = {2004},
  language  = {en}
}
@article{SponagelBaroudFalketal.2004,
  author    = {Sponagel, Stefan and Baroud, G. and Falk, R. and Crookshank, M.},
  title     = {Corrigendum to "Experimental and theoretical investigation of directional permeability of human vertebral cancellous bone for cement infiltration". Baroud, G.; Falk, R.; Crookshank, M.; Sponagel, S.; Steffen, T.},
  series = {Journal of Biomechanics. 37 (2004), H. 2},
  journal   = {Journal of Biomechanics. 37 (2004), H. 2},
  isbn      = {0021-9290},
  pages     = {1802},
  year      = {2004},
  language  = {en}
}
@article{SponagelAkbayBeckeretal.1980,
  author    = {Sponagel, Stefan and Akbay, U. and Becker, E. and Krozer, S.},
  title     = {Instability of slow viscometric flow},
  series = {Mechanics Research Communications. 7 (1980), H. 4},
  journal   = {Mechanics Research Communications. 7 (1980), H. 4},
  isbn      = {0093-6413},
  pages     = {199 -- 204},
  year      = {1980},
  language  = {en}
}