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Lührs, Benjamin (author), Linke, F. (author), Matthes, Sigrun (author), Grewe, V. (author), Yin, F. (author), Shine, K.P. (author)
Air traffic contributes to anthropogenic global warming by about 5% due to CO2 emissions (about 1/3) and non-CO2 effects (about 2/3) primarily caused by emissions of NOx and water vapour as well as the formation of contrails. Since aviation is expected to maintain its trend to grow over the next decades, mitigation measures are required...
abstract 2020
document
Gejadze, I.Y. (author), Monnier, J. (author)
In the context of river hydraulics, we develop the idea of a richer local zoom model superposed to a given global model. The local zoom model (2D shallow water equations in flooded parts) describes additional physical phenomena which are not represented by the basic global model (1D shallow-water equations with storage area). The weak coupling...
conference paper 2006
document
Van Essen, G.M. (author), Van den Hof, P.M.J. (author), Jansen, J.D. (author)
In oil production waterflooding is a popular recovery technology, which involves the injection of water into an oil reservoir. Studies on model-based dynamic optimization of waterflooding strategies have demonstrated that there is a signifcant potential to increase life-cycle performance, measured in Net Present Value. However, in these studies...
conference paper 2010
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Hug-Glanzmann, G. (author), Negenborn, R.R. (author), Andersson, G. (author), De Schutter, B. (author), Hellendoorn, H. (author)
As power systems generally are large interconnected systems controlled by several parties, centralized optimal power flow (OPF) control taking the entire grid into account is often not feasible. To use optimal control in power systems nevertheless, the overall system is decomposed into areas with associated subproblems, which are solved in an...
conference paper 2007
document
Van Doren, J. (author), Markovinovic, R. (author), Jansen, J.D. (author)
During the design of development concepts for the exploitation of oil and gas reservoirs, frequent use is made of numerical simulation of the flow of multi-phase fluids through porous rock. Recently, increased attention has been paid to systematic optimization of well positions and operating parameters (rates, pressures) over the life of the...
conference paper 2006
document
Hinnen, K. (author), Doelman, N. (author), Verhaegen, M. (author)
The problem of finding the closed-loop optimal controller is formulated in an H2-optimal control framework. This provides a natural way to account for the fact that in many AO systems the wavefront phase cannot be measured directly. Given a multi-variable disturbance model of both wavefront slopes and wavefront phases,3 this provides a general...
conference paper 2005
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Doelman, N.J. (author), Hinnen, K.J.G. (author), Stoffelen, F.J.G. (author), Verhaegen, M.H. (author)
An Adaptive Optics (AO) system for astronomy is analysed from a control point of view. The focus is put on the temporal error. The AO controller is identified as a feedback regulator system, operating in closed-loop with the aim of rejecting wavefront disturbances. Limitations on the performance of feedback regulator systems are discussed. The...
conference paper 2004
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Hinnen, K. (author), Verhaegen, M. (author), Doelman, N. (author)
Even though the wavefront distortion introduced by atmospheric turbulence is a dynamic process, its temporal evolution is usually neglected in the adaptive optics (AO) control design. Most AO control systems consider only the spatial correlation in a separate wavefront reconstruction step. By accounting for the temporal evolution of the...
conference paper 2005
document
Van Doren, J. (author), Markovinovic, R. (author), Jansen, J.D. (author)
During the design of development concepts for the exploitation of oil and gas reservoirs, frequent use is made of numerical simulation of the flow of multi-phase fluids through porous rock. Recently, increased attention has been paid to systematic optimization of well positions and operating parameters (rates, pressures) over the life of the...
conference paper 2006
document
Wang, M. (author), Daamen, W. (author), Hoogendoorn, S.P. (author), van Arem, B. (author)
Driver assistance systems support drivers in operating vehicles in a safe, comfortable and efficient way, and thus may induce changes in traffic flow characteristics. This paper put forward a receding horizon control framework to model driver assistance systems. The accelerations of automated vehicles are determined to optimise a cost function,...
conference paper 2012
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Murea, C.M. (author), Vazquez, C. (author)
We study the fluid-structure coupled problem between an incompressible fluid and an elastic curved arch. The fluid flow is modeled by 2-D steady Stokes equations with normal velocity boundary condition on the curved interface and the arch verifies a particular 1-D case of the thin shell theory of Koiter. We present an optimal control formulation...
conference paper 2006
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Evans, Michael (author), Angeli, David (author), Strbac, Goran (author), Tindemans, Simon H. (author)
We present a method to find the maximum magnitude of any supply-shortfall service that an aggregator of energy storage devices is able to sell to a grid operator. This is first demonstrated in deterministic settings, then applied to scenarios in which device availabilities are stochastic. In this case we implement chance constraints on the...
conference paper 2019
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Venhovens, P.J.T. (author)
doctoral thesis 1994
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Hegyi, A. (author)
Dynamic traffic control measures, such as ramp metering and dynamic speed limits, can be used to better utilize the available road capacity. Due to the increasing traffic volumes and the increasing number of traffic jams the interaction between the control measures has increased such that local control measures are often not sufficient anymore....
doctoral thesis 2004
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de Vries, R.A.J. (author)
This thesis presents a novel approach to robust controller design. It describes how linear constraints can be derived on the output of an arbitrary controller, that guarantee robust bounded-input/bounded-output stability and asymptotic perfect tracking of the reference when the external signals become constant. The results are applicable to a...
doctoral thesis 2006
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Hinnen, K.J.G. (author)
Adaptive optics (AO) is a technique to actively correct the wavefront distortions introduced in a light beam as it propagates through a turbulent medium. Nowadays, it is commonly applied in ground-based telescopes to counteract the devastating effect of atmospheric turbulence. This thesis focuses on the control aspects of AO. Whereas most AO...
doctoral thesis 2007
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Song, H. (author)
Adaptive optics (AO), also called as Smart Optics, has received increasing attention in the past decades. The main idea behind AO is to actively sense and compensate the optical aberration in the system such that the image resolution is improved or the light beam is well focused. The applications of AO include ground-based telescopes, scanning...
doctoral thesis 2011
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Hartjes, S. (author)
Civil aviation plays an irreplaceable role in the current global civilization. Even though the 2008 economic crisis has limited growth in the western world, it can only be expected that due to continuing development in the Far East, South America and Africa this role will increase further over the years to come. Also in the field of helicopter...
doctoral thesis 2015
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Wang, M. (author), Treiber, M. (author), Daamen, W. (author), Hoogendoorn, S.P. (author), Van Arem, B. (author)
Driver assistance systems support drivers in operating vehicles in a safe, comfortable and efficient way, and thus may induce changes in traffic flow characteristics. This paper puts forward a receding horizon control framework to model driver assistance and cooperative systems. The accelerations of automated vehicles are controlled to optimise...
journal article 2013
document
Govindarajan, N. (author), De Visser, C.C. (author), Krishnakumar, K. (author)
This paper presents a sparse collocation method for solving the time-dependent Hamilton–Jacobi–Bellman (HJB) equation associated with the continuous-time optimal control problem on a fixed, finite timehorizon with integral cost functional. Through casting the problem in a recursive framework using the value iteration procedure, the value...
journal article 2014
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