@article{WilbringEnningPfaffetal.2020,
  author    = {Wilbring, Daniela and Enning, Manfred and Pfaff, Raphael and Schmidt, Bernd},
  title     = {Neue Perspektiven f{\"u}r die Bahn in der Produktions- und Distributionslogistik durch Prozessautomation},
  series = {ETR - Eisenbahntechnische Rundschau},
  volume    = {69},
  journal   = {ETR - Eisenbahntechnische Rundschau},
  number    = {3},
  issn      = {0013-2845},
  pages     = {15 -- 19},
  year      = {2020},
  language  = {de}
}
@article{CosmaKesslerGebhardtetal.2020,
  author    = {Cosma, Cosmin and Kessler, Julia and Gebhardt, Andreas and Campbell, Ian and Balc, Nicolae},
  title     = {Improving the Mechanical Strength of Dental Applications and Lattice Structures SLM Processed},
  series = {Materials},
  volume    = {13},
  journal   = {Materials},
  number    = {4},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {1996-1944},
  doi       = {10.3390/ma13040905},
  pages     = {1 -- 18},
  year      = {2020},
  abstract  = {To manufacture custom medical parts or scaffolds with reduced defects and high mechanical characteristics, new research on optimizing the selective laser melting (SLM) parameters are needed. In this work, a biocompatible powder, 316L stainless steel, is characterized to understand the particle size, distribution, shape and flowability. Examination revealed that the 316L particles are smooth, nearly spherical, their mean diameter is 39.09 μm and just 10\% of them hold a diameter less than 21.18 μm. SLM parameters under consideration include laser power up to 200 W, 250-1500 mm/s scanning speed, 80 μm hatch spacing, 35 μm layer thickness and a preheated platform. The effect of these on processability is evaluated. More than 100 samples are SLM-manufactured with different process parameters. The tensile results show that is possible to raise the ultimate tensile strength up to 840 MPa, adapting the SLM parameters for a stable processability, avoiding the technological defects caused by residual stress. Correlating with other recent studies on SLM technology, the tensile strength is 20\% improved. To validate the SLM parameters and conditions established, complex bioengineering applications such as dental bridges and macro-porous grafts are SLM-processed, demonstrating the potential to manufacture medical products with increased mechanical resistance made of 316L.},
  language  = {en}
}
@article{KosterScheidweilerTieves2016,
  author    = {Koster, Arie and Scheidweiler, Robert and Tieves, Martin},
  title     = {A flow based pruning scheme for enumerative equitable coloring algorithms},
  series = {A flow based pruning scheme for enumerative equitable coloring algorithms},
  journal   = {A flow based pruning scheme for enumerative equitable coloring algorithms},
  doi       = {10.48550/arXiv.1607.08754},
  pages     = {1 -- 30},
  year      = {2016},
  abstract  = {An equitable graph coloring is a proper vertex coloring of a graph G where the sizes of the color classes differ by at most one. The equitable chromatic number is the smallest number k such that G admits such equitable k-coloring. We focus on enumerative algorithms for the computation of the equitable coloring number and propose a general scheme to derive pruning rules for them: We show how the extendability of a partial coloring into an equitable coloring can be modeled via network flows. Thus, we obtain pruning rules which can be checked via flow algorithms. Computational experiments show that the search tree of enumerative algorithms can be significantly reduced in size by these rules and, in most instances, such naive approach even yields a faster algorithm. Moreover, the stability, i.e., the number of solved instances within a given time limit, is greatly improved. Since the execution of flow algorithms at each node of a search tree is time consuming, we derive arithmetic pruning rules (generalized Hall-conditions) from the network model. Adding these rules to an enumerative algorithm yields an even larger runtime improvement.},
  language  = {en}
}
@article{BeckenbachScheidweiler2016,
  author    = {Beckenbach, Isabel and Scheidweiler, Robert},
  title     = {Perfect ƒ-Matchings and ƒ-Factors in Hypergraphs - A Combinatorial Approach},
  series = {Discrete Mathematics},
  volume    = {240},
  journal   = {Discrete Mathematics},
  number    = {10},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {2192-7782},
  doi       = {10.1016/j.disc.2017.05.005},
  pages     = {2499 -- 2506},
  year      = {2016},
  abstract  = {We prove characterizations of the existence of perfect ƒ-matchings in uniform mengerian and perfect hypergraphs. Moreover, we investigate the ƒ-factor problem in balanced hypergraphs. For uniform balanced hypergraphs we prove two existence theorems with purely combinatorial arguments, whereas for non-uniform balanced hypergraphs we show that the ƒ-factor problem is NP-hard.},
  language  = {en}
}
@article{ScheidweilerTriesch2016,
  author    = {Scheidweiler, Robert and Triesch, Eberhard},
  title     = {A note on the duality between matchings and vertex covers in balanced hypergraphs},
  series = {Journal of Combinatorial Optimization},
  volume    = {32},
  journal   = {Journal of Combinatorial Optimization},
  number    = {2},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1573-2886},
  doi       = {10.1007/s10878-015-9887-5},
  pages     = {639 -- 644},
  year      = {2016},
  abstract  = {We present a new Min-Max theorem for an optimization problem closely connected to matchings and vertex covers in balanced hypergraphs. The result generalizes Kőnig's Theorem (Berge and Las Vergnas in Ann N Y Acad Sci 175:32-40, 1970; Fulkerson et al. in Math Progr Study 1:120-132, 1974) and Hall's Theorem (Conforti et al. in Combinatorica 16:325-329, 1996) for balanced hypergraphs.},
  language  = {en}
}
@article{KilicRaatschenKoerfgenetal.2017,
  author    = {Kilic, S. A. and Raatschen, Hans-J{\"u}rgen and K{\"o}rfgen, B. and Apaydin, N. M. and Astaneh-Asl, A.},
  title     = {FE Model of the Fatih Sultan Mehmet Suspension Bridge Using Thin Shell Finite Elements},
  series = {Arabian Journal for Science and Engineering},
  volume    = {42},
  journal   = {Arabian Journal for Science and Engineering},
  number    = {3},
  publisher = {Springer Nature},
  issn      = {2191-4281},
  doi       = {10.1007/s13369-016-2316-y},
  pages     = {1103 -- 1116},
  year      = {2017},
  abstract  = {This paper presents the results of an eigenvalue analysis of the Fatih Sultan Mehmet Bridge. A high-resolution finite element model was created directly from the available design documents. All physical properties of the structural components were included in detail, so no calibration to the measured data was necessary. The deck and towers were modeled with shell elements. A nonlinear static analysis was performed before the eigenvalue calculation. The calculated natural frequencies and corresponding mode shapes showed good agreement with the available measured ambient vibration data. The calculation of the effective modal mass showed that nine modes had single contributions higher than 5 \% of the total mass. They were in a frequency range up to 1.2 Hz. The comparison of the results for the torsional modes especially demonstrated the advantage of using thin shell finite elements over the beam modeling approach.},
  language  = {en}
}
@article{Pfaff2017,
  author    = {Pfaff, Raphael},
  title     = {Einsatz von offenen Onlinekursen in der Eisenbahnlehre},
  series = {Deine Bahn},
  journal   = {Deine Bahn},
  number    = {1},
  publisher = {Bahn-Fachverlag},
  address   = {Berlin},
  issn      = {0948-7263},
  pages     = {12 -- 16},
  year      = {2017},
  abstract  = {Eigene positive Erfahrungen mit Onlinekursen sowie die geringen Studierendenzahlen in der Pr{\"a}senzlehre gaben den Anstoß zu einem Experiment mit einem offenen Onlinekurs auf der Plattform Udemy. Die Erfahrungen sowohl bei der Erstellung und als auch im Lehrbetrieb waren positiv und f{\"u}hrten zu einer neuen Besch{\"a}ftigung mit Inhalten und Lernenden, getrieben durch die Anforderungen der Lernplattform.},
  language  = {de}
}
@article{Pfaff2017,
  author    = {Pfaff, Raphael},
  title     = {Apps f{\"u}r den G{\"u}terwagen? Wie der G{\"u}terwagen 4.0 die effiziente Integration der G{\"u}terbahn in ERTMS erm{\"o}glicht},
  series = {Ingenieurspiegel},
  journal   = {Ingenieurspiegel},
  number    = {2},
  pages     = {1 -- 2},
  year      = {2017},
  language  = {de}
}
@article{SchwarzGebhardtSchleseretal.2019,
  author    = {Schwarz, Alexander and Gebhardt, Andreas and Schleser, Markus and Popoola, Patricia},
  title     = {New Welding Joint Geometries Manufactured by Powder Bed Fusion from 316L},
  series = {Materials Performance and Characterization 8},
  journal   = {Materials Performance and Characterization 8},
  number    = {in press},
  issn      = {2379-1365},
  doi       = {10.1520/MPC20180096},
  year      = {2019},
  language  = {en}
}
@article{BucurLazarescuPopetal.2019,
  author    = {Bucur, Alexandru and Lazarescu, Lucian and Pop, Grigore Marian and Achimas, Gheorghe and Gebhardt, Andreas},
  title     = {Tribological performance of biodegradable lubricants under different surface roughness of tools},
  series = {Academic Journal of Manufacturing Engineering},
  volume    = {17},
  journal   = {Academic Journal of Manufacturing Engineering},
  number    = {1},
  issn      = {1583-7904},
  pages     = {172 -- 178},
  year      = {2019},
  language  = {en}
}