TY - JOUR A1 - Kämper, Klaus-Peter T1 - Education and Training in MST. Kämper, K.-P.; Picard, A.; Brill, M.; Cassel, D.; Jentsch, A.; Merten, S.; Rollwa, M. JF - Mst-News (2003) Y1 - 2003 SN - 0948-3128 SP - 35 ER - TY - JOUR A1 - Kunkel, Maximilian Hugo A1 - Gebhardt, Andreas A1 - Mpofu, Khumbulani A1 - Kallweit, Stephan T1 - Quality assurance in metal powder bed fusion via deep-learning-based image classification JF - Rapid Prototyping Journal Y1 - 2019 U6 - https://doi.org/10.1108/RPJ-03-2019-0066 SN - 1355-2546 VL - 26 IS - 2 SP - 259 EP - 266 ER - TY - JOUR A1 - Kunkel, Maximilian Hugo A1 - Gebhardt, Andreas A1 - Mpofu, Khumbaulani A1 - Kallweit, Stephan T1 - Statistical assessment of mechanical properties of selective laser melted specimens of stainless steel JF - The International Journal of Advanced Manufacturing Technology N2 - The rail business is challenged by long product life cycles and a broad spectrum of assembly groups and single parts. When spare part obsolescence occurs, quick solutions are needed. A reproduction of obsolete parts is often connected to long waiting times and minimum lot quantities that need to be purchased and stored. Spare part storage is therefore challenged by growing stocks, bound capital and issues of part ageing. A possible solution could be a virtual storage of spare parts which will be 3D printed through additive manufacturing technologies in case of sudden demand. As mechanical properties of additive manufactured parts are neither guaranteed by machine manufacturers nor by service providers, the utilization of this relatively young technology is impeded and research is required to address these issues. This paper presents an examination of mechanical properties of specimens manufactured from stainless steel through the selective laser melting (SLM) process. The specimens were produced in multiple batches. This paper interrogates the question if the test results follow a normal distribution pattern and if mechanical property predictions can be made. The results will be put opposite existing threshold values provided as the industrial standard. Furthermore, probability predictions will be made in order to examine the potential of the SLM process to maintain state-of-the-art mechanical property requirements. Y1 - 2018 U6 - https://doi.org/10.1007/s00170-018-2040-8 SN - 0268-3768 VL - 98 IS - 5-8 SP - 1409 EP - 1431 PB - Springer CY - London 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 - https://doi.org/10.48550/arXiv.1607.08754 N1 - Lehrstuhl II für Mathematik, RWTH Aachen University SP - 1 EP - 30 ER - TY - JOUR A1 - Klocke, Martina T1 - Study Units in the CIM-Oriented Study Factory JF - Qualification for Computer-Integrated Manufacturing. Hrsg.: Felix Rauner Y1 - 1995 SN - 3-540-19971-3 SP - 38 EP - 51 PB - Springer CY - Berlin [u.a.] 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 - https://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 - Kessler, Julia A1 - Balc, Nicolae A1 - Gebhardt, Andreas A1 - Abbas, Karim T1 - Basic Research on Lattice Structures Focused on the Tensile Strength JF - Applied Mechanics and Materials Y1 - 2015 U6 - https://doi.org/10.4028/www.scientific.net/AMM.808.193 SN - 1662-7482 N1 - MTeM ; October 14-16, 2015, Cluj-Napoca, Romania VL - Vol. 808 SP - 193 EP - 198 PB - Trans Tech Publications CY - Bäch ER - TY - JOUR A1 - Kallweit, Stephan A1 - Willert, Chris A1 - Dues, Michael A1 - Müller, Ulrich T1 - PIV for Volume Flow Metering / Kallweit, Stephan ; Willert, Chris ; Dues, Michael ; Müller, Ulrich ; Lederer, Thomas Y1 - 2008 N1 - 14th International Symposium on Applications of Laser Techniques to Fluid Mechanics, 2008-07-07 - 2008-07-10, Lisbon (Portugal) SP - 6 S. ER - TY - JOUR A1 - Kallweit, Stephan A1 - Vanlanduit, S. A1 - Vanherzeele, J. A1 - Brouns, M. T1 - Time resolved PIV reconstruction of periodic flows / Vanlanduit, S. ; Vanherzeele, J. ; Kallweit, S. ; Brouns, M. ; Guillaume, P. JF - PIV'07, 7th International Symposium on Particle Image Velocimetry, Roma, IT, Sep 11-14, 2007 Y1 - 2007 N1 - PIV, Internional Symposium on Particle Image Velocimetry, 7 ; Datei: Vanlanduit.pdf SP - 1 EP - 14 ER - TY - JOUR A1 - Kallweit, Stephan A1 - Uchiyama, R. A1 - Siekmann, H. T1 - Fault Diagnostic Method for Pump Running Conditions Based on Process Modeling and Neural Network / Uchiyama, R. ; Kallweit, S. ; Siekmann, H. JF - International Journal of Rotating Machinery. 4 (1998), H. 1 Y1 - 1998 SN - 1542-3034 SP - 49 EP - 59 ER - TY - JOUR A1 - Kallweit, Stephan A1 - Schimpf, Axel T1 - Photogrammetric Particle Image Velocimetry / Schimpf, Axel ; Kallweit, Stephan JF - Particle image velocimetry : recent improvements; proceedings of the Europiv 2 Workshop held in Zaragoza, Spain, March 31 - April 1, 2003 / edited by M. Stanislas ... Y1 - 2003 SN - 3-540-21423-2 SP - 295 PB - Springer CY - Berlin ER - TY - JOUR A1 - Kallweit, Stephan A1 - Kaminsky, Radoslav A1 - Rossi, Massimiliano A1 - Morbiducci, Umberto T1 - PIV Measurements of Flows in Artificial Heart Valves / Kaminsky, Radoslav ; Kallweit, Stephan ; Rossi, Massimiliano ; Morbiducci, Umberto ; Scalise, Lorenzo JF - Particle Image Velocimetry - New Developments and Recent Applications Y1 - 2008 SN - 978-3-540-73528-1 N1 - Topics in Applied Physics SP - 55 EP - 72 ER - TY - JOUR A1 - Kallweit, Stephan A1 - Kaminsky, R. A1 - Rossi, M. A1 - Scalise, L. T1 - PIV Measurements with high temporal Resolution behind Artificial Heart Valves / Kaminsky, R. ; Rossi, M. ; Scalise, L. ; Kallweit, S. ; Verdonck, P. JF - Proceedings of the 6th International Symposium on Particle Image Velocimetry Y1 - 2005 N1 - link zum abstract PB - Caltech CY - Pasadena, CA ER - TY - JOUR A1 - Kallweit, Stephan A1 - Kaminsky, R. A1 - Rossi, M. A1 - Morbiducci, U. T1 - Time resolved PIV technique for high temporal resolution measurements of prosthetic heart valves fluid dynamics / Kaminsky, R. ; Rossi, M. ; Morbiducci, U. ; Scalise, L. ; Catellini, P. ; Kallweit, S. ; Verdonck, P. ; Grigioni, M. JF - The International Journal of Artificial Organs. 28 (2005), H. 9 Y1 - 2005 SN - 1724-6040 N1 - Abstracts: XXXII Annual ESAO Congress, 5-8 October 2005, Bologna - Italy SP - 946 ER - TY - JOUR A1 - Kallweit, Stephan A1 - Kaminsky, R. A1 - Rossi, M. A1 - Morbiducci, U. T1 - 2D PIV Study of the flow downstream : Two prototypes of a ney monoleaflet artificial aortic heart valve prosthesis / Kaminsky, R. ; Kramm, K. ; Weber, H. J. ; Simons, A. P. ; Kallweit, S. ; Verdonck, P. R. JF - The International Journal of Artificial Organs. 28 (2005), H. 9 Y1 - 2005 SN - 1724-6040 N1 - Abstracts: XXXII Annual ESAO Congress, 5-8 October 2005, Bologna - Italy SP - 921 ER - TY - JOUR A1 - Kallweit, Stephan A1 - Kaminsky, R. A1 - Rossi, M. A1 - Morbiducci, U. T1 - 3D PIV measurements of prosthetic heart valve dynamics / Kaminsky, R. ; Rossi, M. ; Morbiducci, U. ; Scalise, L. ; Castellini, P. ; Kallweit, S. ; Verdonck, P. ; Grigioni, M. JF - The International Journal of Artificial Organs. 28 (2005), H. 9 Y1 - 2005 SN - 1724-6040 N1 - Abstracts: XXXII Annual ESAO Congress, 5-8 October 2005, Bologna - Italy SP - 868 ER - TY - JOUR A1 - Kallweit, Stephan A1 - Helbing, M. A1 - Orglmeister, R. A1 - Siekmann, H. E. T1 - Image Processing Techniques with Neural Networks for Flow Visualization in Rotating Machinery / Helbing, M. ; Orgimeiste, R. [Orglmeister, R.] ; Kallweit, S. ; Siekmann, H. E. ; Dues, M. ; Cronemeyer, J. JF - FLUCOME '94 : the 4th Triennial International Symposium on Fluid Control, Measurement and Visualization; August 29 - September 1, 1994, Toulouse, France, International Congress Centre, DIGORA-Labège / CERT/ONERA. General chairman Patrick Hebrard Y1 - 1994 SP - 87 EP - 94 CY - Toulouse ER - TY - JOUR A1 - Kallweit, Stephan A1 - Dues, M. W. A1 - Siekmann, H. E. T1 - Spectral Analysis of Pressure Fluctuations and Velocity Fields as Investigated on Propeller Pumps / Dues, M. W. ; Kallweit, S. D. ; Siekmann, H. E. JF - Preprints : Fifth International Symposium on Transport Phenomena and Dynamics of Rotating Machinery (ISROMAC-5) : May 8 - 11, 1994, Maui Marriott Hotel, Kaanapali, Maui, Hawaii, U.S.A / sponsored by Pacific Center of Thermal-Fluids Engineering. [W.-J. Yang, chairman] / Vol. B. Y1 - 1994 N1 - International Symposium on Transport Phenomena and Dynamics of Rotating Machinery 5, 1994, Kaanapali, Hawaii SP - 98 EP - 112 ER - TY - JOUR A1 - Kallweit, Stephan A1 - Dues, M. A1 - Siekmann, H. T1 - Particle-Image-Velocimetry (PIV) in rotierenden Maschinen / Dues, M. ; Kallweit, S. ; Siekmann, H. JF - Lasermethoden in der Strömungsmesstechnik, 3. Fachtagung der Deutschen Gesellschaft für Laser-Anemometrie (GALA), Bremen, DE, 5.-7. Sep, 1994 Y1 - 1994 SN - 3-8265-0162-4 N1 - Lasermethoden in der Strömungsmesstechnik, Fachtagung, 3 SP - 19.1 EP - 19-5 PB - Shaker CY - Aachen ER - TY - JOUR A1 - Hötter, Jan-Steffen A1 - Fateri, Miranda A1 - Gebhardt, Andreas T1 - Selective laser melting of metals: desktop machines open up new chances even for small companies JF - Advanced materials research N2 - Additive manufacturing (AM) of metal parts by using Selective Laser Melting (SLM) has become a powerful tool mostly in the area of automotive, aerospace engineering and others. Especially in the field of dentistry, jewelry and related branches that require individualized or even one-of-a-kind products, the direct digital manufacturing process opens up new ways of design and manufacturing. In these fields, mostly small and medium sized businesses (SME) are operating which do not have sufficient human and economic resources to invest in this technology. But to stay competitive, the application of AM can be regarded as a necessity. In this situation a new desktop machine (Realizer SLM 50) was introduced that cost about 1/3 of a shop floor SLM machine and promises small quality parts. To find out whether the machine really is an alternative for SMEs the University of Applied Science, Aachen, Germany, designed, build and optimized typical parts from the dentistry and the jewelry branches using CoCr and silver material, the latter being new with this application. The paper describes the SLM procedure and how to find and optimize the most important parameters. The test is accompanied by digital simulation in order to verify the build parameters and to plan future builds. The procedure is shown as well as the resulting parts made from CoCr and silver material. Y1 - 2012 U6 - https://doi.org/10.4028/www.scientific.net/AMR.622-623.461 SN - 1662-8985 (E-Journal); 1022-6680 (Print) VL - 622-623 SP - 461 EP - 465 PB - Trans Tech Publ. CY - Baech ER -