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Kazei, V.V. (author), Ponomarenko, A.V. (author), Troyan, V.N. (author), Kashtan, B.M. (author), Mulder, W.A. (author)
Full waveform inversion suffers from local minima, due to a lack of low frequencies in the data. A reflector below the zone of interest may, however, help in recovering the long-wavelength components of a velocity perturbation, as demonstrated in a paper by Mora. With the Born approximation for the perturbation in a reference model consisting of...
conference paper 2012
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Mercado Velasco, G.A. (author), Mulder, M. (author), Van Paassen, M.M. (author)
Air traffic controller workload is considered to be an important limiting factor to the growth of air traffic. The difficulty of an air traffic control task can be analyzed through examining the problem’s solution space, that is, all possible vector commands that satisfy the constraints of safety, productivity and efficiency. But apart from...
conference paper 2010
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Huiskes, M.J. (author), Plessix, R.E. (author), Mulder, W.A. (author)
We propose a finite-difference scheme for the simulation of seismic waves interacting with 3-D freesurface topography. The intended application is velocity model building by acoustic full-waveform inversion (FWI). The scheme follows an immersed boundary approach for wave equations in the firstorder stress-velocity formulation, discretized on a...
conference paper 2016
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Van Wieringen, A.T. (author), Pool, D.M. (author), Van Paassen, M.M. (author), Mulder, M. (author)
Due to the significant translational heave motion at the pilot station associated with changes in aircraft pitch attitude, themotion cueing for aircraft pitchmaneuvering typically requires significant heave washout filtering. Previous studies that attempted to motivate choices in the motion cueing strategy for pitch maneuvering based on...
conference paper 2011
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Correia Gracio, B.J. (author), Van Paassen, M.M. (author), Mulder, M. (author), Wentink, M. (author)
Generally, motion simulators present motion and visual cues different from each other due to the physical limitations of the motion platform. Nonetheless, high fidelity motion platforms are capable of simulating some maneuvers one-to-one, i.e., motion cues equal to visual cues. However, one-to-one simulation is normally not preferred by subjects...
conference paper 2010
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De Jong, P.M.A. (author), De Vos, K. (author), Borst, C. (author), Van Paassen, M.M. (author), Mulder, M. (author)
Two of the major projects in ATM development, SESAR and NextGen, both fore- cast the use of 4D trajectories as an intermediate phase in the development of full Performance Based Trajectories. Using 4D trajectories, the full positional and time coordinates of the aircraft are known throughout the planned trajectory. During approach, when reduced...
conference paper 2011
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Zhebel, E. (author), Minisini, S. (author), Kononov, A. (author), Mulder, W.A. (author)
The finite-difference method is widely used for time-domain modelling of the wave equation because of its ease of implementation of high-order spatial discretization schemes, parallelization and computational efficiency. However, finite elements on tetrahedral meshes are more accurate in complex geometries near sharp interfaces. We compared the...
conference paper 2012
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Nieuwenhuizen, F.M. (author), Van Paasen, M.M. (author), Mulder, M. (author), Bülthoff, H.H. (author)
A simulated model of the MPI Stewart platform can be used to identify the influence of motion system characteristics on human control behaviour in active closed-loop control experiments on the SIMONA Research Simulator. In this paper, a previously identified model of the MPI Stewart platform was analysed with describing function measurements,...
conference paper 2010
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Van Baelen, D. (author), Ellerbroek, J. (author), van Paassen, M.M. (author), Mulder, M. (author)
Current Airbus aircraft use a fly-by-wire control device: a passive spring-damper system which generates, without any force feedback, an electrical signal to the flight control computer. Additionally, a hard flight envelope protection system is used which can limit the inputs of the pilot when approaching the edges of the flight envelope. To...
conference paper 2018
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Pisupati, P.B. (author), Mulder, W.A. (author), Drijkoningen, G.G. (author)
With single-parameter full waveform inversion, estimating the inverse of the Hessian matrix will accelerate the convergence, but is computationally expensive. Therefore, an approximate Hessian, which is easier to compute, is often used. Similarly, in the case of multi-parameter full waveform inversion, the computation of the Hessian terms that...
conference paper 2014
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Jönsthövel, T.B. (author), Oosterlee, C.W. (author), Mulder, W.A. (author)
We evaluated multigrid techniques for 3D diffusive electromagnetism. The Maxwell equations and Ohm's law were discretised on stretched grids, with stretching in all coordinate directions. We compared standard multigrid to alternative multigrid approaches with linewise smoothing and semi-coarsening, both as a stand-alone solver and as a...
conference paper 2006
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Miletovic, I. (author), Pool, D.M. (author), Stroosma, O. (author), Pavel, M.D. (author), Wentink, M (author), Mulder, M. (author)
The fidelity of a rotorcraft flight simulator is influenced by many factors, such as the vehicle dynamic model and the motion cueing algorithm (MCA). To quantify the fidelity of a simulator objectively requires detailed knowledge of human pilot perception and control behaviour that is not yet available. As a consequence, subjective...
conference paper 2017
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Yu, H. (author), Mulder, J.A. (author)
This work concentrates on the development of an optimization technique which is capable of minimizing the noise impact of an arriving aircraft by optimizing its flight trajectory. Actions needed from pilots to gradually establish the landing configuration are considered because it is expected that the pilot workload throughout this phase should...
conference paper 2012
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Shamasundar, R. (author), Mulder, W.A. (author)
The second-order formulation of the wave equation is often used for spectral-element discretizations. For some applications, however, a first-order formulation may be desirable. It can, in theory, provide much better accuracy in terms of numerical dispersion if the consistent mass matrix is used and the degree of the polynomial basis functions...
conference paper 2016
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Mulder, F.A. (author), Verlinden, J.C. (author), Dukalski, R.R. (author)
This paper explores the amount of motion simulation required to influence presence and immersion on a dinghy sailing simulator. We specifically focused on the effects of roll, pitch and heave, when sailing an course with up-, side-and down-wind sections in a virtual environment. A real dingy was mounted on a 6 Degrees of Freedom (DOF) Stewart...
conference paper 2012
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Leurs, B. (author), Schelling, J. (author), Mulder, I.J. (author)
a problem due to a lack of space, a group of 50 design students had to move to another building. Having a dedicated space in an historical building turned the initial setback into an opportunity. Design students usually do not have the luxury of having their own design studio. By observing and interviewing the students over a period of 5 months,...
conference paper 2013
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Mulder, W.A. (author)
Migration velocity analysis for the two-way wave equation based on focusing extended migration images at zero subsurface offset are sensitive to the presence of multiples. Even after thorough multiple suppression, remnant multiple energy can lead to conflicting events that will focus at different velocities, one for the primary and another for...
conference paper 2013
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De Groot, S. (author), De Winter, J.C.F. (author), Wieringa, P.A. (author), Mulder, M. (author)
Braking to a full stop at a prescribed target position is a driving manoeuvre regularly used in experiments to investigate driving behaviour or to test vehicle acceleration feedback systems in simulators. Many different performance measures have been reported in the literature for analysing braking. These may or may not be useful to analyse the...
conference paper 2010
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Maas, P.J. (author), Grobbe, N. (author), Slob, E.C. (author), Mulder, W.A. (author)
For multi-parameter problems, such as the seismoelectric system, sensitivity analysis through resolution functions is a low-cost, fast method of determining whether measured fields are sensitive to certain subsurface parameters. We define a seismoelectric resolution function for the inversion of a bulk density perturbation. The synthetic data...
conference paper 2015
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Mulder, M. (author)
conference paper 1998
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