TY - CONF A1 - Arnold, B. A1 - Burger, H. A1 - Drott, U. A1 - Hahn, Oliver A1 - Kaun, S. A1 - Laue, S. A1 - Noll-Minor, M. A1 - Raue, J. A1 - Schlütter, F. A1 - Ziemann, M. T1 - Pigmentveränderungen - Verschwärzen von Bleizinngelb T2 - Jahrestagung Archäometrie und Denkmalpflege 2010 T2 - Jahrestagung Archäometrie und Denkmalpflege 2010 CY - Bochum, Germany DA - 2010-09-15 PY - 2010 AN - OPUS4-21777 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Robens-Radermacher, Annika A1 - Lacy Jr., T. E. A1 - Bednarcyk, B. A. A1 - Pineda, E. J. A1 - Arnold, S. M. A1 - Ricks, T. M. T1 - Solution of the nonlinear high-fidelity generalized method of cells micromechanics relations via order-reduction techniques JF - Mathematical Problems in Engineering N2 - The High-Fidelity Generalized Method of Cells (HFGMC) is one technique, distinct from traditional finite-element approaches, for accurately simulating nonlinear composite material behavior. In this work, the HFGMC global system of equations for doubly periodic repeating unit cells with nonlinear constituents has been reduced in size through the novel application of a Petrov-Galerkin Proper Orthogonal Decomposition order-reduction scheme in order to improve its computational efficiency. Order-reduced models of an E-glass/Nylon 12 composite led to a 4.8–6.3x speedup in the equation assembly/solution runtime while maintaining model accuracy. This corresponded to a 21–38% reduction in total runtime.Thesignificant difference in assembly/solution and total runtimes was attributed to the evaluation of integration point inelastic field quantities; this step was identical between the unreduced and order-reduced models. Nonetheless, order-reduced techniques offer the potential to significantly improve the computational efficiency of multiscale calculations. KW - High-Fidelity KW - Micromechanics KW - HFGMC PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-445303 DO - https://doi.org/10.1155/2018/3081078 SN - 1024-123X SN - 1563-5147 VL - 2018 SP - Article ID 3081078-1 EP - 11 PB - Hindawi Publishing Corporation CY - Kairo, Ägypten AN - OPUS4-44530 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Knaust, Christian A1 - Festag, S. A1 - Brüne, M. A1 - Dietrich, Matthes A1 - Amecke-Mönninghoff, Stephan A1 - Konrath, B. A1 - Arnold, L. T1 - Modellierung eines Brandes in einer U-Bahn-Station: Validierung von Rechenmodellen auf der Grundlage von Feldversuchen T2 - Magdeburger Brand- und Explosionsschutztage 2017 N2 - Mittels Propan-Brennern mit einer Brennerleistung 750 kW wurden in einer U-Bahn-Station Heißgasversuche durchgeführt und die zeitlichen und örtlichen Verteilungen der physikalischen Größen (Stoffkonzentration, Temperatur und Rauchgasdichte) erfasst. Laborversuche sowie die Feldversuche sind Validierungsgrundlage für ANSYS CFX und FDS und die später im Rechenmodell der U-Bahn-Station zur Untersuchung der Grundströmung und Rauchausbreitung verwendeten mathematisch-physikalischen Modelle. Der Aufsatz stellt das Projekt ORPHEUS vor und diskutiert die ersten Ergebnisse. T2 - Magdeburger Brand- und Explosionsschutztage 2017 CY - Magdeburg, Germany DA - 23.03.2017 KW - Rechenmodelle KW - Ansys CFX KW - FDS KW - Computational fluid dynamics KW - CFD KW - Rauchausbreitung KW - Validierung KW - U-Bahn KW - Brandszenarien KW - Modellierung von Bränden PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-396694 SN - 978-3-00-056201-3 DO - https://doi.org/10.978.300/0562013 SP - 1 EP - 12 PB - Otto-von-Guericke-Universität Magdeburg CY - Magdeburg AN - OPUS4-39669 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wunderle, B. A1 - Onken, T. A1 - Heilmann, J. A1 - Silbernagl, Dorothee A1 - Arnold, J. A1 - Bieniek, T. A1 - Pufall, R. T1 - Reliability of sputtered thin aluminium films under accelerated stress testing by vibration loading and modeling T2 - Reliability of sputtered thin aluminium films under accelerated stress testing by vibration loading and modeling N2 - Aluminium is still one of the most important contact metallisations for power electronic chips like MOSFETs or IGBTs. With a large difference in thermal expansion coefficients (CTEs) between aluminium and silicon and the temperatures generated in hot-spots during high power transients, these layers are prone to failure due to thermo-mechanical fatigue. Usually lifetime assessment is done by subjecting dedicated test specimens to standardised stress tests as e.g. active or passive thermal cycling. This paper proposes a novel method for accelerated stress testing and lifetime modelling of thin aluminium films in the high-cycle fatigue regime by isothermal mechanical loading. The proposed novel test method is suggested to complement or replace resource-demanding thermal cycling tests and allow simple in-situ monitoring of failure. T2 - 6th Electronic System-Integration Technology Conference (ESTC) CY - Grenoble, France DA - 13.09.2016 KW - Semiconductor device reliability KW - Thermal expansion KW - AFM KW - Vibrations KW - Nanoroughness KW - Accelerated stress testing KW - Active thermal cycling KW - Power electronic chips KW - Sputtered thin aluminium film KW - Thermomechanical fatigue PY - 2016 DO - https://doi.org/10.1109/ESTC.2016.7764458 SP - 1 EP - 14 PB - IEEE AN - OPUS4-43595 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -