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Veltman, M.M. (author), van Keulen, J. (author), Smits, A. E.H. (author), Voogt, J. M. (author)When addressing problems with wicked tendencies in higher professional education, students experience complexity, uncertainty, and value divergence. Furthermore, they are confronted with disciplinary, organisational, and sector boundaries. Prior research has revealed variability in students’ experiences and boundary-crossing behaviour when...journal article 2024
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Rhodes, Miriam J. (author), van Keulen, J. (author), Gijsel, Martine A. R. (author), Visscher, Adrie J. (author)Integrated language, science and technology (ILS&T) instruction is a complex task for primary school teachers that requires professional development. Task-centered educational approaches such as the four-component instructional design (4C/ID) model are well suited for the development of complex professional skills. This article describes the...journal article 2024
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van Keulen, D.C. (author)The thixotropic properties of contemporary mortars allow the insertion of mortar in small vertical seams by using a mortar pump without the need for traditional formwork. In such a seam, a vertical mortar connection for the transfer of shear forces can be created by simply adding a profile to the mortar-to-concrete interfaces. In this way a...doctoral thesis 2023
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van Keulen, J. (author), Hellendoorn, Annika (author), van den Berghe, Rianne (author), Ploeger, Erik (author), Petersen, Hans (author), Schutte, Patrick (author)Een onderzoek naar het gebruik van sociale robotica in primair onderwijs ten behoeve van de ontwikkeling van technische en sociale vaardigheden voor leerlingen met een autismespectrumstoornis (ASS) <br/>RoboWise: An investigation into the use of social robotics in primary education for developing technological and social skills in children with...report 2023
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van den Boom, S.J. (author), Abedi, Reza (author), van Keulen, A. (author), Aragon, A.M. (author)Phononic crystals can be designed to show band gaps—ranges of frequencies whose propagation is strongly attenuated in the material. In essence, their working principle is based on destructive interference of waves reflecting from the periodic arrangement of material interfaces (i.e., Bragg scattering). Consequently, capturing accurately the...journal article 2023
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Delissen, A.A.T.M. (author), van Keulen, A. (author), Langelaar, Matthijs (author)The design of high-performance mechatronic systems is very challenging, as it requires delicate balancing of system dynamics, the controller, and their closed-loop interaction. Topology optimization provides an automated way to obtain systems with superior performance, although extension to simultaneous optimization of both topology and...journal article 2023
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Ranjan, R. (author), Langelaar, Matthijs (author), van Keulen, A. (author), Ayas, C. (author)Computational process modelling of metal additive manufacturing has gained significant research attention in recent past. The cornerstone of many process models is the transient thermal response during the AM process. Since deposition-scale modelling of the thermal conditions in AM is computationally expensive, spatial and temporal...journal article 2023
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de Frel, Daan L. (author), Wicks, Hope (author), Bakk, Zsuzsa (author), van Keulen, Nicole (author), Atsma, D.E. (author), Janssen, Veronica R. (author)Background and aims: Adopting healthier diets can drastically improve societal health. Our environment plays a crucial role in daily dietary choices and hospitals in particular can stimulate patients to adopt healthier eating habits. Unfortunately, no robust clinically applicable cuing tools exist to help guide in-hospital dietary...journal article 2023
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Kranenburg, W.M. (author), van Keulen, Daan (author), Gerritsma, A. (author), Huismans, Y. (author)We investigate the changes in surface water salinity intrusion lengths for estuaries around the world under influence of climate change. To do this, we make use of information from global data sets on present river geometry and present and predicted future river discharges, mean sea levels and tidal ranges, which we combine with various models...conference paper 2023
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van den Boom, S.J. (author), Zhang, J. (author), van Keulen, A. (author), Aragon, A.M. (author)The published article contains a mistake in the notation of the strain–displacement matrix (Formula presented.) in Voigt notation concerning the isoparametric mapping and in the notation of the corresponding derivatives. As the mistakes relate only to the notation, and the implementation in the code was done correctly, they bear no...journal article 2023
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Zhang, L. (author), Zhang, Y. (author), van Keulen, A. (author)High computational costs are encountered in topology optimization problems of geometrically nonlinear structures since intensive use has to be made of incremental-iterative finite element simulations. To alleviate this computational intensity, reduced-order models (ROMs) are explored in this paper. The proposed method targets ROM bases...journal article 2023
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Li, Z. (author), Xu, M. (author), Norte, R.A. (author), Aragon, A.M. (author), van Keulen, A. (author), Alijani, F. (author), Steeneken, P.G. (author)In recent years, the Q-factor of Si 3 N 4 nanomechanical resonators has significantly been increased by soft-clamping techniques using large and complex support structures. To date, however, obtaining similar performance with smaller supports has remained a challenge. Here, we make use of torsion beam supports to tune the Q-factor of Si 3 N 4...journal article 2023
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Wang, W. (author), van Keulen, A. (author), Wu, J. (author)Additive manufacturing of metal parts involves phase transformations and high temperature gradients which lead to uneven thermal expansion and contraction, and, consequently, distortion of the fabricated components. The distortion has a great influence on the structural performance and dimensional accuracy, e.g., for assembly. It is therefore...journal article 2023
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van Maren, D.S. (author), Maushake, Christian (author), Mol, Jan-Willem (author), van Keulen, Daan (author), Jürges, Jens (author), Vroom, Julia (author), Schuttelaars, H.M. (author), Gerkema, Theo (author), Schulz, Kirstin (author)An extensive field campaign, the Ems-Dollard Measurements (EDoM), was executed in the Ems Estuary, bordering the Netherlands and Germany, aimed at better understanding the mechanisms that drive the exchange of water and sediments between a relatively exposed outer estuary and a hyper-turbid tidal river. More specifically, the reasons for the...journal article 2023
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Ranjan, R. (author), Chen, Z. (author), Ayas, C. (author), Langelaar, Matthijs (author), van Keulen, A. (author)Overheating is a major issue especially in metal Additive Manufacturing (AM) processes, leading to poor surface quality, lack of dimensional precision, inferior performance and/or build failures. A 3D density-based topology optimization (TO) method is presented which addresses the issue of local overheating during metal AM. This is achieved...journal article 2023
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Theulings, M.J.B. (author), Langelaar, Matthijs (author), van Keulen, A. (author), Maas, Robert (author)Modeling of fluid flows in density-based topology optimization forms a longstanding challenge. Methods based on the Navier–Stokes equations with Darcy penalization (NSDP equations) are widely used in fluid topology optimization. These methods use porous materials with low permeability to represent the solid domain. Consequently, they suffer...journal article 2023
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Ranjan, R. (author), Ayas, C. (author), Langelaar, Matthijs (author), van Keulen, A. (author)A novel constraint to prevent local overheating is presented for use in topology optimization (TO). The very basis for the constraint is the Additive Manufacturing (AM) process physics. AM enables fabrication of highly complex topologically optimized designs. However, local overheating is a major concern especially in metal AM processes...journal article 2022
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Numic, A. (author), Blad, Thijs (author), van Keulen, A. (author)In this paper, a novel alternative method of stiffness compensation in buckled mechanisms is investigated. This method involves the use of critical load matching, i.e., matching the first two buckling loads of a mechanism. An analytical simply supported five-bar linkage model consisting of three rigid links, a prismatic slider joint, and four...journal article 2022
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Veltman, M. E. (author), van Keulen, J. (author), Voogt, Joke (author)Professionals are increasingly involved in attempts to under- stand and address problems with wicked tendencies, which require crossing boundaries between disciplines, organisa- tions and stakeholder perspectives. This multiple-case study investigated six higher professional education courses in order to develop better understanding of how...journal article 2022
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van Keulen, J. (author), Petersen, Hans (author), Ploeger, Erik (author), van den Berghe, Rianne (author), Hellendoorn, Annika (author), Schutte, Patrick (author)Hoe deze lessenserie werkt<br/>Je leest nu de docenthandleiding, hier vind je een overzicht van de opbouw van de lessenserie en de bijbehorende materialen. Deze lessenserie bestaat uit zes thema’s. Ieder thema duurt een week en heeft eigen doelen op het gebied van samenwerken en programmeren. Bij ieder thema hoort een docentkaart en...book 2022