@inproceedings{KleineKallweitMichauxetal.2016, author = {Kleine, Harald and Kallweit, Stephan and Michaux, Frank and Havermann, Marc and Olivier, Herbert}, title = {PIV Measurement of Shock Wave Diffraction}, series = {18th International Symposium on Applications of Laser Techniques to Fluid Mechanics, 2016, Lissabon}, booktitle = {18th International Symposium on Applications of Laser Techniques to Fluid Mechanics, 2016, Lissabon}, pages = {1 -- 14}, year = {2016}, language = {en} } @inproceedings{SchleupenEngemannBagherietal.2016, author = {Schleupen, Josef and Engemann, Heiko and Bagheri, Mohsen and Kallweit, Stephan}, title = {The potential of SMART climbing robot combined with a weatherproof cabin for rotor blade maintenance}, series = {17th European Conference on Composite Materials - ECCM, Munich, Germany}, booktitle = {17th European Conference on Composite Materials - ECCM, Munich, Germany}, pages = {1 -- 8}, year = {2016}, 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} } @inproceedings{KoenigWolf2016, author = {K{\"o}nig, Johannes Alexander and Wolf, Martin R.}, title = {A new definition of competence developing games - and a framework to assess them}, series = {ACHI 2016 : The Ninth International Conference on Advances in Computer-Human Interactions}, booktitle = {ACHI 2016 : The Ninth International Conference on Advances in Computer-Human Interactions}, isbn = {978-1-61208-468-8}, pages = {95 -- 97}, year = {2016}, abstract = {There are different types of games that try to make use of the motivation of a gaming situation in learning contexts. This paper introduces the new terminology 'Competence Developing Game' (CDG) as an umbrella term for all games with this intention. Based on this new terminology, an assessment framework has been developed and validated in scope of an empirical study. Now, all different types of CDGs can be evaluated according to a defined and uniform set of assessment criteria and, thus, are comparable according to their characteristics and effectiveness.}, language = {en} } @inproceedings{GregorioFatigatiKallweit2015, author = {Gregorio, Fabrizio de and Fatigati, Giovanni and Kallweit, Stephan}, title = {Tiltrotor airframe flow field characterization by SPIV}, series = {11th International Symposium on Partivle Image Velocimetry - PIV15 , Santa Barbara, California, Sept 14-16, 2015}, booktitle = {11th International Symposium on Partivle Image Velocimetry - PIV15 , Santa Barbara, California, Sept 14-16, 2015}, pages = {15 S.}, year = {2015}, language = {en} } @article{FateriGebhardt2015, author = {Fateri, Miranda and Gebhardt, Andreas}, title = {Additive manufactured mechanical disentanglement lock}, series = {RTejournal - Forum f{\"u}r Rapid Technologie}, volume = {12}, journal = {RTejournal - Forum f{\"u}r Rapid Technologie}, publisher = {Fachhochschule Aachen}, address = {Aachen}, issn = {1614-0923}, url = {http://nbn-resolving.de/urn:nbn:de:0009-2-42147}, year = {2015}, language = {en} } @inproceedings{GrossmannGabrielliHerdrichetal.2015, author = {Großmann, Agnes and Gabrielli, Roland Antonius and Herdrich, Georg and Fasoulas, Stefanos and Schnauffer, Peter and Middendorf, Peter and Fateri, Miranda and Gebhardt, Andreas}, title = {Overview of the MultiRob 3D Lunar Industrial Development Project}, series = {Conference Contribution for the 30th ISTS, Kobe, Japan, 04.07.-10.07.2015}, booktitle = {Conference Contribution for the 30th ISTS, Kobe, Japan, 04.07.-10.07.2015}, pages = {8 S.}, year = {2015}, language = {en} } @article{KesslerBalcGebhardtetal.2015, author = {Kessler, Julia and Balc, Nicolae and Gebhardt, Andreas and Abbas, Karim}, title = {Basic Research on Lattice Structures Focused on the Tensile Strength}, series = {Applied Mechanics and Materials}, volume = {Vol. 808}, journal = {Applied Mechanics and Materials}, publisher = {Trans Tech Publications}, address = {B{\"a}ch}, issn = {1662-7482}, doi = {10.4028/www.scientific.net/AMM.808.193}, pages = {193 -- 198}, year = {2015}, language = {en} } @inproceedings{FateriGebhardtGabriellietal.2015, author = {Fateri, Miranda and Gebhardt, Andreas and Gabrielli, Roland Antonius and Herdrich, Georg and Fasoulas, Stefanos and Großmann, Agnes and Schnauffer, Peter and Middendorf, Peter}, title = {Additive Manufacturing of Lunar Regolith for Extra-terrestrial Industry Plant}, series = {International Symposium on Space Technology and Science (ICTS). July 2015, Kobe, Japan}, booktitle = {International Symposium on Space Technology and Science (ICTS). July 2015, Kobe, Japan}, pages = {5 S.}, year = {2015}, language = {en} } @inproceedings{GabrielliMathiesGrossmannetal.2015, author = {Gabrielli, Roland Antonius and Mathies, Johannes and Großmann, Agnes and Herdrich, Georg and Fasoulas, Stefanos and Middendorf, Peter and Fateri, Miranda and Gebhardt, Andreas}, title = {Space Propulsion Considerations for a Lunar Take Off Industry Based on Regolith}, series = {International Symposium on Space Technology and Science (ISTS). July 2015, Kobe, Japan}, booktitle = {International Symposium on Space Technology and Science (ISTS). July 2015, Kobe, Japan}, year = {2015}, language = {en} } @inproceedings{FateriGebhardtRenftle2015, author = {Fateri, Miranda and Gebhardt, Andreas and Renftle, Georg}, title = {Additive Manufacturing of Drainage Segments for Cooling System of Crucibles Melting Furnaces}, series = {International Conference and Expo on Advanced Ceramics and Composites, (ICACC). January 2015, Florida, USA}, booktitle = {International Conference and Expo on Advanced Ceramics and Composites, (ICACC). January 2015, Florida, USA}, pages = {9 S.}, year = {2015}, abstract = {The cooling process in induction based crucible melting furnaces for Industrial applications is one of the important and challenging factors in production and safety engineering. Accordingly, proper implementation of the cooling system of the furnace using optimum cooling guides and fail-safe features are critical in order to improve the safety of the process. Regarding this, manufacturing of porous material with high electrical isolation for the drainage segments of the cooling channels is examined in this study. Consequently, various geometries with different porosities using glass and ceramic powder are fabricated using Selective Laser Sintering (SLS) process. The manufactured parts are examined in a prototype furnace testing and the feasibility of the SLS manufacturing of parts for this application is discussed.}, language = {en} } @article{FateriGebhardt2015, author = {Fateri, Miranda and Gebhardt, Andreas}, title = {Selective Laser Melting of Soda-Lime Glass Powder}, series = {International Journal of Applied Ceramic Technology}, volume = {12}, journal = {International Journal of Applied Ceramic Technology}, number = {1}, publisher = {Wiley-Blackwell}, address = {Oxford}, issn = {1744-7402}, doi = {10.1111/ijac.12338}, pages = {53 -- 61}, year = {2015}, language = {en} } @article{FateriGebhardt2015, author = {Fateri, Miranda and Gebhardt, Andreas}, title = {Process Parameters Development of Selective Laser Melting of Lunar Regolith for On-Site Manufacturing Applications}, series = {International Journal of Applied Ceramic Technology}, volume = {12}, journal = {International Journal of Applied Ceramic Technology}, number = {1}, publisher = {Wiley-Blackwell}, address = {Oxford}, isbn = {1744-7402}, doi = {10.1111/ijac.12326}, pages = {46 -- 52}, year = {2015}, language = {en} } @inproceedings{NakagawaMichauxKallweitetal.2015, author = {Nakagawa, Masaki and Michaux, Frank and Kallweit, Stephan and Maeda, Kazuhiro}, title = {Unsteady flow measurements in the wake behind a wind-tunnel car model by using high-speed planar PIV}, series = {11TH International Symposium on Particle Image Velocimetry - PIV15 Santa Barbara, California, September 14-16, 2015}, booktitle = {11TH International Symposium on Particle Image Velocimetry - PIV15 Santa Barbara, California, September 14-16, 2015}, pages = {21 S.}, year = {2015}, abstract = {This study investigates unsteady characteristics of the wake behind a 28\%-scale car model in a wind tunnel using highspeed planar particle image velocimetry (PIV). The car model is based on a hatchback passenger car that is known to have relatively high fluctuations in its aerodynamic loads. This study primarily focuses on the lateral motion of the flow on the horizontal plane to determine the effect of the flow motion on the straight-line stability and the initial steering response of the actual car on a track. This paper first compares the flow fields in the wake behind the above mentioned model obtained using conventional and high-speed planar PIV, with sampling frequencies of 8 Hz and 1 kHz, respectively. Large asymmetrically coherent flow structures, which fluctuate at frequencies below 2 Hz, are observed in the results of highspeed PIV measurements, whereas conventional PIV is unable to capture these features of the flow owing to aliasing. This flow pattern with a laterally swaying motion is represented by opposite signs of cross-correlation coefficients of streamwise velocity fluctuations for the two sides of the car model. Effects of two aerodynamic devices that are known to reduce the fluctuation levels of the aerodynamic loads are then extensively investigated. The correlation analyses reveal that these devices indeed reduce the fluctuation levels of the flow and the correlation values around the rear combination-lamp, but it is found that the effects of these devices are different around the c-pillar.}, language = {en} } @inproceedings{KilicRaatschenAstanehAsletal.2015, author = {Kilic, S. A. and Raatschen, Hans-J{\"u}rgen and Astaneh-Asl, A. and Apaydin, N. M.}, title = {Finite element modeling of the Fatih Sultan Mehmet Suspension Bridge}, series = {Multi-Span Large Bridges - Proceedings of the International Conference on Multi-Span Large Bridges}, booktitle = {Multi-Span Large Bridges - Proceedings of the International Conference on Multi-Span Large Bridges}, publisher = {CRC Press}, address = {Leiden}, isbn = {9781138027572}, pages = {1169 -- 1173}, year = {2015}, language = {en} } @inproceedings{Wollert2015, author = {Wollert, J{\"o}rg}, title = {Wireless systems for machinery safety : Requirements and solutions for wireless real time systems}, series = {16th International Conference on Research and Education in Mechatronics (REM), 2015}, booktitle = {16th International Conference on Research and Education in Mechatronics (REM), 2015}, isbn = {978-3-945728-01-7}, doi = {10.1109/REM.2015.7380377}, pages = {88 -- 91}, year = {2015}, language = {en} } @inproceedings{FerreinKallweitScholletal.2015, author = {Ferrein, Alexander and Kallweit, Stephan and Scholl, Ingrid and Reichert, Walter}, title = {Learning to Program Mobile Robots in the ROS Summer School Series}, series = {Proceedings 6th International Conference on Robotics in Education (RiE 15)}, booktitle = {Proceedings 6th International Conference on Robotics in Education (RiE 15)}, pages = {6 S.}, year = {2015}, abstract = {The main objective of our ROS Summer School series is to introduce MA level students to program mobile robots with the Robot Operating System (ROS). ROS is a robot middleware that is used my many research institutions world-wide. Therefore, many state-of-the-art algorithms of mobile robotics are available in ROS and can be deployed very easily. As a basic robot platform we deploy a 1/10 RC cart that is wquipped with an Arduino micro-controller to control the servo motors, and an embedded PC that runs ROS. In two weeks, participants get to learn the basics of mobile robotics hands-on. We describe our teaching concepts and our curriculum and report on the learning success of our students.}, language = {en} } @inproceedings{AlhwarinFerreinGebhardtetal.2015, author = {Alhwarin, Faraj and Ferrein, Alexander and Gebhardt, Andreas and Kallweit, Stephan and Scholl, Ingrid and Tedjasukmana, Osmond Sanjaya}, title = {Improving additive manufacturing by image processing and robotic milling}, series = {2015 IEEE International Conference on Automation Science and Engineering (CASE), Aug 24-28, 2015 Gothenburg, Sweden}, booktitle = {2015 IEEE International Conference on Automation Science and Engineering (CASE), Aug 24-28, 2015 Gothenburg, Sweden}, doi = {10.1109/CoASE.2015.7294217}, pages = {924 -- 929}, year = {2015}, language = {en} }