TY - CHAP A1 - Fateri, Miranda A1 - Gebhardt, Andreas A1 - Gabrielli, Roland Antonius A1 - Herdrich, Georg A1 - Fasoulas, Stefanos A1 - Großmann, Agnes A1 - Schnauffer, Peter A1 - Middendorf, Peter T1 - Additive Manufacturing of Lunar Regolith for Extra-terrestrial Industry Plant T2 - International Symposium on Space Technology and Science (ICTS). July 2015, Kobe, Japan Y1 - 2015 ER - TY - CHAP A1 - Gabrielli, Roland Antonius A1 - Mathies, Johannes A1 - Großmann, Agnes A1 - Herdrich, Georg A1 - Fasoulas, Stefanos A1 - Middendorf, Peter A1 - Fateri, Miranda A1 - Gebhardt, Andreas T1 - Space Propulsion Considerations for a Lunar Take Off Industry Based on Regolith T2 - International Symposium on Space Technology and Science (ISTS). July 2015, Kobe, Japan Y1 - 2015 ER - TY - CHAP A1 - Fateri, Miranda A1 - Gebhardt, Andreas A1 - Renftle, Georg T1 - Additive Manufacturing of Drainage Segments for Cooling System of Crucibles Melting Furnaces T2 - International Conference and Expo on Advanced Ceramics and Composites, (ICACC). January 2015, Florida, USA N2 - 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. Y1 - 2015 ER - TY - JOUR A1 - Pfaff, Raphael T1 - Praxisnahe Ausbildung im Fach Schienenfahrzeugtechnik JF - Deine Bahn Y1 - 2015 SN - 0172-4479 IS - 8 SP - 52 EP - 55 PB - Eisenbahn-Fachverlag CY - Mainz ER - TY - JOUR A1 - Pfaff, Raphael A1 - Schmidt, Bernd A1 - Pinders, Udo T1 - Energieeffizienz steigern durch Rekuperationseinrichtungen JF - Deine Bahn Y1 - 2015 SN - 0172-4479 IS - 5 SP - 50 EP - 53 PB - Eisenbahn-Fachverlag CY - Mainz ER - TY - JOUR A1 - Gebhardt, Andreas T1 - 3D-Druck ist überall. Modische Accessoires, Kleidung, Medikamente, Nahrungsmittel, Autos, Häuser, Waffen, Büsten, Musikinstrumente - alles geht JF - Kunststoffe Y1 - 2015 SN - 0023-5563 VL - 105 IS - 10 SP - 62 EP - 70 PB - Hanser CY - München ER - TY - CHAP A1 - Kilic, S. A. A1 - Raatschen, Hans-Jürgen A1 - Astaneh-Asl, A. A1 - Apaydin, N. M. T1 - Finite element modeling of the Fatih Sultan Mehmet Suspension Bridge T2 - Multi-Span Large Bridges - Proceedings of the International Conference on Multi-Span Large Bridges Y1 - 2015 SN - 9781138027572 SP - 1169 EP - 1173 PB - CRC Press CY - Leiden ER - TY - CHAP A1 - Wollert, Jörg T1 - Wireless systems for machinery safety : Requirements and solutions for wireless real time systems T2 - 16th International Conference on Research and Education in Mechatronics (REM), 2015 Y1 - 2015 SN - 978-3-945728-01-7 U6 - http://dx.doi.org/10.1109/REM.2015.7380377 SP - 88 EP - 91 ER - TY - CHAP A1 - Nakagawa, Masaki A1 - Kallweit, Stephan A1 - Michaux, Frank A1 - Hojo, Teppei T1 - Typical Velocity Fields and Vortical Structures around a Formula One Car, based on Experimental Investigations using Particle Image Velocimetry T2 - SAE International Journal of Passenger Cars - Mechanical Systems Y1 - 2016 U6 - http://dx.doi.org/10.4271/2016-01-1611 SN - 1946-4002 ER - TY - JOUR A1 - Wollert, Jörg T1 - Industrial Internet of Things : Seifenblase oder Revolution JF - Elektronik Y1 - 2016 SN - 0013-5658 N1 - gedruckt in der Bereichsbibliothek Eupener Str. unter der Signatur Z 263 IS - 7 SP - 39 EP - 45 PB - WEKA-Fachmedien CY - München ER - TY - BOOK A1 - Gebhardt, Andreas A1 - Hötter, Jan-Steffen T1 - Additive manufacturing : 3D printing for prototyping and manufacturing Y1 - 2016 SN - 978-1-56990-582-1 ; 978-1-56990-583-8 PB - Hanser Publishers CY - Munich ER - TY - BOOK A1 - Gebhardt, Andreas A1 - Kessler, Julia A1 - Thurn, Laura T1 - 3D-Drucken: Grundlagen und Anwendungen des additive manufacturing (AM) Y1 - 2016 SN - 978-3-446-44672-4 U6 - http://dx.doi.org/10.3139/9783446448452 PB - Hanser CY - München ET - 2., neu bearbeitete und erweiterte Auflage ER - TY - JOUR A1 - Koster, Arie A1 - Scheidweiler, Robert A1 - Tieves, Martin T1 - A flow based pruning scheme for enumerative equitable coloring algorithms JF - A flow based pruning scheme for enumerative equitable coloring algorithms N2 - 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. Y1 - 2016 U6 - http://dx.doi.org/10.48550/arXiv.1607.08754 N1 - Lehrstuhl II für Mathematik, RWTH Aachen University SP - 1 EP - 30 ER - TY - JOUR A1 - Beckenbach, Isabel A1 - Scheidweiler, Robert T1 - Perfect ƒ-Matchings and ƒ-Factors in Hypergraphs - A Combinatorial Approach JF - Discrete Mathematics N2 - 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. Y1 - 2016 U6 - http://dx.doi.org/10.1016/j.disc.2017.05.005 SN - 2192-7782 N1 - Als Volltext auch bei ZIB (Zuse Institute Berlin) VL - 240 IS - 10 SP - 2499 EP - 2506 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Scheidweiler, Robert A1 - Triesch, Eberhard T1 - A note on the duality between matchings and vertex covers in balanced hypergraphs JF - Journal of Combinatorial Optimization N2 - 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. KW - Hall’s Theorem KW - Koenig’s Theorem KW - Duality KW - Balanced hypergraph KW - Hypergraph KW - Vertex cover KW - Matching Y1 - 2016 U6 - http://dx.doi.org/10.1007/s10878-015-9887-5 SN - 1573-2886 N1 - Lehrstuhl II für Mathematik RWTH Aachen VL - 32 IS - 2 SP - 639 EP - 644 PB - Springer CY - Berlin ER - TY - JOUR A1 - Kilic, S. A. A1 - Raatschen, Hans-Jürgen A1 - Körfgen, B. A1 - Apaydin, N. M. A1 - Astaneh-Asl, A. T1 - FE Model of the Fatih Sultan Mehmet Suspension Bridge Using Thin Shell Finite Elements JF - Arabian Journal for Science and Engineering N2 - 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. KW - Suspension bridge KW - 3D nonlinear finite element model KW - Thin shell finite elements KW - Natural frequency KW - Effective modal mass Y1 - 2017 U6 - http://dx.doi.org/10.1007/s13369-016-2316-y SN - 2191-4281 VL - 42 IS - 3 SP - 1103 EP - 1116 PB - Springer Nature ER - TY - JOUR A1 - Rieper, Harald A1 - Gebhardt, Andreas A1 - Stucker, Brent T1 - Selective Laser Melting of the Eutectic Silver-Copper Alloy Ag 28 wt % Cu JF - RTejournal - Forum für Rapid Technologie N2 - The aim of this work was to perform a detailed investigation of the use of Selective Laser Melting (SLM) technology to process eutectic silver-copper alloy Ag 28 wt. % Cu (also called AgCu28). The processing occurred with a Realizer SLM 50 desktop machine. The powder analysis (SEM-topography, EDX, particle distribution) was reported as well as the absorption rates for the near-infrared (NIR) spectrum. Microscope imaging showed the surface topography of the manufactured parts. Furthermore, microsections were conducted for the analysis of porosity. The Design of Experiments approach used the response surface method in order to model the statistical relationship between laser power, spot distance and pulse time. KW - SLM KW - Response Surface Method KW - Porositat KW - Eutectic Silver Copper alloy KW - Additive Manufacturing Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?nbn:de:0009-2-44141 SN - 1614-0923 VL - 13 ER - TY - BOOK A1 - Gebhardt, Andreas T1 - Additive Fertigungsverfahren : Additive Manufacturing und 3D-Drucken für Prototyping - Tooling - Produktion Y1 - 2016 SN - 978-3-446-44401-0 ; 978-3-446-44539-0 U6 - http://dx.doi.org/10.3139/9783446445390 N1 - Verfügbar in der Bereichsbibliothek Eupener Straße unter 21 ZHU 25(5); verfügbar in der Bereichsbibliothek Jülich unter 61 ZHU 26(5) PB - Hanser CY - München ET - 5. aktualisierte und erweiterte Auflage ER - TY - JOUR A1 - Haag, S. A1 - Zontar, D. A1 - Schleupen, Josef A1 - Müller, T. A1 - Brecher, C. T1 - Chain of refined perception in self-optimizing assembly of micro-optical systems JF - Journal of sensors and sensor systems N2 - Today, the assembly of laser systems requires a large share of manual operations due to its complexity regarding the optimal alignment of optics. Although the feasibility of automated alignment of laser optics has been shown in research labs, the development effort for the automation of assembly does not meet economic requirements – especially for low-volume laser production. This paper presents a model-based and sensor-integrated assembly execution approach for flexible assembly cells consisting of a macro-positioner covering a large workspace and a compact micromanipulator with camera attached to the positioner. In order to make full use of available models from computer-aided design (CAD) and optical simulation, sensor systems at different levels of accuracy are used for matching perceived information with model data. This approach is named "chain of refined perception", and it allows for automated planning of complex assembly tasks along all major phases of assembly such as collision-free path planning, part feeding, and active and passive alignment. The focus of the paper is put on the in-process image-based metrology and information extraction used for identifying and calibrating local coordinate systems as well as the exploitation of that information for a part feeding process for micro-optics. Results will be presented regarding the processes of automated calibration of the robot camera as well as the local coordinate systems of part feeding area and robot base. Y1 - 2014 U6 - http://dx.doi.org/10.5194/jsss-3-87-2014 SN - 2194-878X VL - 3 IS - 1 SP - 87 EP - 95 PB - Copernicus Publ. CY - Göttingen ER - TY - BOOK A1 - Feuerriegel, Uwe T1 - Verfahrenstechnik mit EXCEL: Verfahrenstechnische Berechnungen effektiv durchführen und professionell dokumentieren Y1 - 2016 SN - 978-3-658-02902-9 U6 - http://dx.doi.org/10.1007/978-3-658-02903-6 N1 - 152 Abbildungen, 94 Abbildungen in Farbe Gedruckt in der Bibliothek unter der Signatur: 21 ZNK 11 PB - Springer Fachmedien CY - Wiesbaden ER -