TY - JOUR AU - Bobzin, K. AU - Kalscheuer, C. AU - Grundmeier, Guido AU - de los Arcos, T. AU - Kollmann, S. AU - Carlet, M. ID - 36872 JF - Surface and Coatings Technology KW - Materials Chemistry KW - Surfaces KW - Coatings and Films KW - Surfaces and Interfaces KW - Condensed Matter Physics KW - General Chemistry SN - 0257-8972 TI - Oxidation stability of chromium aluminum oxynitride hard coatings VL - 449 ER - TY - JOUR AU - Neßlinger, Vanessa AU - Welzel, Stefan AU - Rieker, Florian AU - Meinderink, Dennis AU - Nieken, Ulrich AU - Grundmeier, Guido ID - 36873 JF - Macromolecular Reaction Engineering KW - Polymers and Plastics KW - General Chemical Engineering KW - General Chemistry SN - 1862-832X TI - Thin Organic‐Inorganic Anti‐Fouling Hybrid‐Films for Microreactor Components ER - TY - JOUR AB - In industrial x-ray computed tomography (CT), the application of more complex scan paths in comparison to the typical circular trajectory (${360}^{\circ}$ rotation of the measurement object) can extend the potential of CT. One way to enable such 3D scan trajectories is to use a 6-degrees-of-freedom (DOF) object manipulator system. In our case, a hexapod is mounted on top of the rotary table of a commercial CT scanner. This allows for adaptive tilting of the measurement object during the scan. For high accuracy, the geometry calibration of such setups is typically done using the x-ray projections of a calibrated multi-sphere object. Contrary to this, here, we demonstrate a procedure that is based on only a single sphere and can therefore experimentally be implemented with low effort. Using the intrinsic geometry parameters of the CT device as prior information, the hexapod coordinate system with respect to the CT machine coordinate system is determined by means of a one-step optimization approach. The resulting parameters are used to calculate projection matrices that enable the volume reconstruction for 3D scan trajectories. The method is validated using simulated x-ray images and experimental investigations including dimensional measurements. For the used setup, geometric measurement results for 3D scan trajectories that are calibrated with the presented method show in sum increased errors compared to the circular scans. A limited pose accuracy of the manipulator system is discussed as a potential cause. The results nevertheless indicate that the presented method is generally feasible for dimensional CT measurements provided that the pose accuracy is sufficient. The calibration procedure can therefore be a low-cost and easier to implement alternative compared to trajectory calibration methods based on multi-sphere objects, but with a tendency towards lower measurement accuracy. The methodology can in principle be transferred to different setups with 6-DOF manipulator systems, e.g. C-arm CT devices with a robot arm. AU - Butzhammer, Lorenz AU - Müller, Andreas Michael AU - Hausotte, Tino ID - 34264 IS - 1 JF - Measurement Science and Technology KW - Applied Mathematics KW - Instrumentation KW - Engineering (miscellaneous) SN - 0957-0233 TI - Calibration of 3D scan trajectories for an industrial computed tomography setup with 6-DOF object manipulator system using a single sphere VL - 34 ER - TY - JOUR AU - Henksmeier, Tobias AU - Schulz, Johann Friedemann AU - Kluth, Elias AU - Feneberg, Martin AU - Goldhahn, Rüdiger AU - Sanchez, Ana M. AU - Voigt, Markus AU - Grundmeier, Guido AU - Reuter, Dirk ID - 36804 JF - Journal of Crystal Growth TI - Remote epitaxy of In(x)Ga(1-x)As(001) on graphene covered GaAs(001) substrates VL - 593 ER - TY - GEN AB - The Julia programming language has evolved into a modern alternative to fill existing gaps in scientific computing and data science applications. Julia leverages a unified and coordinated single-language and ecosystem paradigm and has a proven track record of achieving high performance without sacrificing user productivity. These aspects make Julia a viable alternative to high-performance computing's (HPC's) existing and increasingly costly many-body workflow composition strategy in which traditional HPC languages (e.g., Fortran, C, C++) are used for simulations, and higher-level languages (e.g., Python, R, MATLAB) are used for data analysis and interactive computing. Julia's rapid growth in language capabilities, package ecosystem, and community make it a promising universal language for HPC. This paper presents the views of a multidisciplinary group of researchers from academia, government, and industry that advocate for an HPC software development paradigm that emphasizes developer productivity, workflow portability, and low barriers for entry. We believe that the Julia programming language, its ecosystem, and its community provide modern and powerful capabilities that enable this group's objectives. Crucially, we believe that Julia can provide a feasible and less costly approach to programming scientific applications and workflows that target HPC facilities. In this work, we examine the current practice and role of Julia as a common, end-to-end programming model to address major challenges in scientific reproducibility, data-driven AI/machine learning, co-design and workflows, scalability and performance portability in heterogeneous computing, network communication, data management, and community education. As a result, the diversification of current investments to fulfill the needs of the upcoming decade is crucial as more supercomputing centers prepare for the exascale era. AU - Churavy, Valentin AU - Godoy, William F AU - Bauer, Carsten AU - Ranocha, Hendrik AU - Schlottke-Lakemper, Michael AU - Räss, Ludovic AU - Blaschke, Johannes AU - Giordano, Mosè AU - Schnetter, Erik AU - Omlin, Samuel AU - Vetter, Jeffrey S AU - Edelman, Alan ID - 36879 TI - Bridging HPC Communities through the Julia Programming Language ER - TY - JOUR AU - Bonnard, Bernard AU - Rouot, Jérémy AU - Wembe Moafo, Boris Edgar ID - 35206 JF - Mathematical Control and Related Fields KW - Applied Mathematics KW - Control and Optimization KW - General Medicine SN - 2156-8472 TI - Accessibility properties of abnormal geodesics in optimal control illustrated by two case studies ER - TY - JOUR AU - Bonnard, B. AU - Cots, O. AU - Gergaud, J. AU - Wembe Moafo, Boris Edgar ID - 33869 JF - Systems & Control Letters KW - Electrical and Electronic Engineering KW - Mechanical Engineering KW - General Computer Science KW - Control and Systems Engineering SN - 0167-6911 TI - Abnormal geodesics in 2D-Zermelo navigation problems in the case of revolution and the fan shape of the small time balls VL - 161 ER - TY - GEN AU - Büchel, Daniel AU - Visser, Anton AU - Lehmann, Tim AU - Baumeister, Jochen ID - 36938 TI - Frontal theta power increases during table tennis play – indications for neurophysiological demands during open-skill sports? ER - TY - GEN AU - Lehmann, Tim AU - Visser, Anton AU - Havers, Tim AU - Büchel, Daniel AU - Baumeister, Jochen ID - 36937 IS - 9S SN - 1530-0315 TI - Surface Instability Modulates Cortical Information Processing In Multi-Joint Compound Movements VL - 54 ER - TY - JOUR AU - Constantiou, Ioanna AU - Mukkamala, Alivelu AU - Sjöklint, Mimmi AU - Trier, Matthias ID - 36961 JF - European Journal of Information Systems KW - Library and Information Sciences KW - Information Systems SN - 0960-085X TI - Engaging with self-tracking applications: how do users respond to their performance data? ER - TY - JOUR AB - AbstractFurther innovation in the field of selective laser sintering (SLS) is strongly connected to the availability of new materials since the market is dominated by polyamide 12 (>90%). The aim of this publication is to develop a descriptive model for the droplet formation process in a Filament Extension Atomizer to predict the applicability to exploit further polymers for the SLS process. The feasibility was tested, investigated and characterized using a “Dripping out of a nozzle” setup for uniaxial extension. The droplet formation process was then observed via high-speed camera imaging and classified for certain parameters. The experiments were carried out using semi-diluted polyethylene oxide (600–4000 kg/mol), glycerol and water solutions as model fluids. Driven by the Plateau-Rayleigh instability, different types of spherical droplets were observed and various droplet formation mechanisms demonstrated and analyzed. Based on the experimental results, a predictive model is derived to describe various essential parameters. AU - Neukötter, Moritz AU - Jesinghausen, Steffen AU - Schmid, Hans-Joachim ID - 31035 JF - Rheologica Acta KW - Rheology KW - SLS KW - Lasersintering KW - exensional rheology SN - 0035-4511 TI - Model droplet formation in extensional filament stretching within a Filament Extension Atomizer ER - TY - JOUR AU - Thomas, Sven ID - 36988 IS - 4 JF - Technology and Language TI - Language in the Age of Mechanical Reproduction VL - 3 ER - TY - JOUR AB - Iso-octane is frequently used as a surrogate fuel or as a component in primary reference fuel blends when low-temperature combustion strategies in engines are investigated. To develop control strategies for these engines, the reaction kinetics of iso-octane must be known starting from the low temperatures and intermediate pressures before ignition to the high temperatures and pressures of combustion. This work adds new experimental data sets to the validation data for reaction mechanism development by investigating the oxidation of iso-octane in stoichiometric mixtures in a flow reactor at pressures of p = 1, 10, and 20 bar and 473K ≤ T ≤ 973 K. The experimental data are compared to simulations with recent reaction mechanisms [Atef et al., Combustion and Flame 178, (2017), Bagheri et al., Combustion and Flame 212, (2020), Cai et al., Proceedings of the Combustion Institute 37, (2018), Fang et al., Combustion and Flame 214, (2020)]. The comparison between experimental and simulated mole fractions as function of temperature show reasonable agreement for all investigated pressures. In particular, the experimentally observed onset of low-temperature reactivity above a certain pressure, the shift of the negative temperature coefficient (NTC) regime with increasing pressure to higher temperatures, and the acceleration of the high-temperature chemistry are captured well in the simulations. Deviations between experimental and simulated results are discussed in detail for the reactivity of iso-octane and some key intermediates such as 2,2,4,4-tetramethyl-tetrahydrofuran, iso-butene and acetone at low temperatures. AU - Shaqiri, S. AU - Kaczmarek, D. AU - vom Lehn, F. AU - Beeckmann, J. AU - Pitsch, H. AU - Kasper, Tina ID - 36815 JF - Frontiers in Energy Research KW - Economics and Econometrics KW - Energy Engineering and Power Technology KW - Fuel Technology KW - Renewable Energy KW - Sustainability and the Environment SN - 2296-598X TI - Experimental Investigation of the Pressure Dependence of Iso-Octane Combustion VL - 10 ER - TY - JOUR AU - Hoener, Martin AU - Kasper, Tina ID - 36817 JF - Combustion and Flame KW - General Physics and Astronomy KW - Energy Engineering and Power Technology KW - Fuel Technology KW - General Chemical Engineering KW - General Chemistry SN - 0010-2180 TI - Nitrous acid in high-pressure oxidation of CH4 doped with nitric oxide: Challenges in the isomer-selective detection and quantification of an elusive intermediate VL - 243 ER - TY - JOUR AU - Knyazkov, Denis A. AU - Cherepanov, Andrey V. AU - Kiselev, Vitaly G. AU - Gerasimov, Ilya E. AU - Kasper, Tina AU - Shmakov, Andrey G. ID - 36810 JF - Proceedings of the Combustion Institute KW - Physical and Theoretical Chemistry KW - Mechanical Engineering KW - General Chemical Engineering SN - 1540-7489 TI - Experimental and kinetic modeling study of the positive ions in premixed ethylene flames over a range of equivalence ratios ER - TY - JOUR AB - Owing to the implementation of multi-material construction methods in modern lightweight construction and the associated use of adhesive bonding technology, thermally induced relative displacements of the joining partners occur during the curing process. The resulting extremely complex thermo-chemo-mechanical stresses can influence the properties of the adhesive layers and reduce the load-bearing capacity. In this study, experiments are conducted to examine the influence of process-related thermal relative displacements on the mechanical properties of adhesives. The results show an anisotropy of the mechanical properties of the pre-deformed adhesive layers, depending on the magnitude and direction of the relative displacement. AU - Beule, Felix AU - Teutenberg, Dominik AU - Meschut, Gerson ID - 31330 JF - Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering KW - Mechanical Engineering KW - Aerospace Engineering SN - 0954-4070 TI - Directional dependence of the mechanical properties of structural adhesive joints with curing-induced pre-deformations ER - TY - JOUR AU - Kaczmarek, D. AU - Bierkandt, T. AU - Rudolph, C. AU - Grimm, S. AU - Shaqiri, S. AU - Höner, M. AU - Gaiser, N. AU - Atakan, B. AU - Köhler, M. AU - Hemberger, P. AU - Kasper, Tina ID - 36814 JF - Applications in Energy and Combustion Science KW - Fuel Technology KW - Energy (miscellaneous) KW - Chemical Engineering (miscellaneous) SN - 2666-352X TI - Activation effect of ozone and DME on the partial oxidation of natural gas surrogates and validation of pressure-dependent ozone decomposition ER - TY - JOUR AU - Kaczmarek, Dennis AU - Rudolph, Charlotte AU - Atakan, Burak AU - Kasper, Tina ID - 36811 JF - Proceedings of the Combustion Institute KW - Physical and Theoretical Chemistry KW - Mechanical Engineering KW - General Chemical Engineering SN - 1540-7489 TI - Kinetic investigation of the ozone-assisted partial oxidation of fuel-rich natural gas mixtures at elevated pressure ER - TY - JOUR AU - Bierkandt, Thomas AU - Hemberger, Patrick AU - Oßwald, Patrick AU - Gaiser, Nina AU - Hoener, Martin AU - Krüger, Dominik AU - Kasper, Tina AU - Köhler, Markus ID - 36813 JF - Proceedings of the Combustion Institute KW - Physical and Theoretical Chemistry KW - Mechanical Engineering KW - General Chemical Engineering SN - 1540-7489 TI - A combustion chemistry study of tetramethylethylene in a laminar premixed low-pressure hydrogen flame ER - TY - JOUR AB - Many mechanical material properties show a dependence on the strain rate, e.g. yield stress or elongation at fracture. The quantitative description of the material behavior under dynamic loading is of major importance for the evaluation of crash safety. This is carried out using numerical methods and requires characteristic values for the materials used. For the standardized determination of dynamic characteristic values in sheet metal materials, tensile tests performed according to the guideline from [1]. A particular challenge in dynamic tensile tests is the force measurement during the test. For this purpose, strain gauges are attached on each specimen, wired to the measuring equipment and calibrated. This is a common way to determine a force signal that is as low in vibration and as free of bending moments as possible. The preparation effort for the used strain gauges are enormous. For these reasons, an optical method to determine the force by strain measurement using DIC is presented. The experiments are carried out on a high speed tensile testing system. In combioantion with a 3D DIC high speed system for optical strain measurement. The elastic deformation of the specimen in the dynamometric section is measured using strain gauges and the optical method. The measured signals are then compared to validate the presented method. The investigations are conducted using the dual phase steel material HCT590X and the aluminum material EN AW-6014 T4. Strain rates of up to 240 s-1 are investigated. AU - Böhnke, Max AU - Unruh, Eduard AU - Sell, Stanislaw AU - Bobbert, Mathias AU - Hein, David AU - Meschut, Gerson ID - 33002 JF - Key Engineering Materials KW - Mechanical Engineering KW - Mechanics of Materials KW - General Materials Science SN - 1662-9795 TI - Functionality Study of an Optical Measurement Concept for Local Force Signal Determination in High Strain Rate Tensile Tests VL - 926 ER -