Pages
 1
 2
 document

Kooij, Robert (author), Zegeling, André (author)We present a mechanical model for an oscillator with one degree of freedom under the influence of a flowing medium. Under fairly general conditions we show that the ensuing differential equation has at most two limit cycles and we give examples where exactly two limit cycles will occur. The implications of this result are that it is possible...journal article 2023
 document

Bunk, Yannick (author)The development of a highfidelity fluidstructure interaction tool for the simulation of aircraft flight dynamics in the subsonic flow regime is presented. The tool combines a highfidelity largeeddy simulation code with an immersed boundary method, a multibody solver and a loose coupling scheme between fluid and solid. The development of the...master thesis 2022
 document

Loram, Ian (author), Gollee, Henrik (author), van de Kamp, C. (author), Gawthrop, Peter (author)Objective: To explain the 0.22Hz oscillation in human balance. Motivation: Oscillation (0.22 Hz) in the control signal (ankle moment) is sustained independently of external disturbances and exaggerated in Parkinson's disease. Does resonance or limit cycles in the neurophysiological feedback loop cause this oscillation? We investigate two...journal article 2022
 document

Duinmeijer, S.P.A. (author), Clemens, F.H.L.R. (author)Experiments are conducted in a Ø600 mm tank to analyse the 3D motion of buoyant particles in the freesurface vortex flow. The experiments revealed two stages in the particle motion: stage 1 is the helical motion along the vortex air core and stage 2 is the axial motion inside the vortex core. The stage 1 motion is sensitive to the particle’s...journal article 2021
 document

Kooij, Robert (author), Zegeling, André (author)For a family of twodimensional predatorprey models of Gause type, we investigate the simultaneous occurrence of a center singularity and a limit cycle. The family is characterized by the fact that the functional response is nonanalytical and ehibits group defense. We prove the eistence and uniqueness of the limit cycle using a new theorem...journal article 2021
 document

Gasull, Armengol (author), Geyer, A. (author), Mañosa, Víctor (author)It is well known that the existence of traveling wave solutions (TWS) for many partial differential equations (PDE) is a consequence of the fact that an associated planar ordinary differential equation (ODE) has certain types of solutions defined for all time. In this paper we address the problem of persistence of TWS of a given PDE under small...journal article 2021
 document

Zegeling, André (author), Kooij, Robert (author)The research presented in this paper compares the occurrence of limit cycles under different bifurcation mechanisms in a simple system of twodimensional autonomous predator–prey ODEs. Surprisingly two unconventional approaches, for a singular system and for a system with a center, turn out to produce more limit cycles than the traditional...journal article 2021
 document

Kieft, Bas (author)The most widely applied feedback controller is PID. This controller gains its popularity because of the ease of design through loop shaping, since PID can be analyzed in the frequency domain. However, PID is limited by linearity. Reset control is a nonlinear addition to PID control. Through linearization techniques it can be designed by...master thesis 2020
 document

Zegeling, André (author), Kooij, Robert (author)We study the occurrence of limit cyles in a model for twospecies predatorprey interaction (referred to as Holling I). This model is based on the phenomenological fitting of the socalled functional response function to observed data in nature by a continuous, piecewise differentiable function. Of the original models presented by Holling it...journal article 2020
 document

Gasull, A. (author), Geyer, A. (author), Mañosas, F. (author)We show that a family of certain definite integrals forms a Chebyshev system if two families of associated functions appearing in their integrands are Chebyshev systems as well. We apply this criterion to several examples which appear in the context of perturbations of periodic nonautonomous ODEs to determine bounds on the number of isolated...journal article 2020
 document

Smeets, Lucy (author)Massspring systems are commonly used in structural components. Understanding their characteristics and pitfalls is an important issue, combining physics and mathematics to prevent such systems from resonating and causing structures to weaken or collapse. This way, suitable solutions can be found such as the use of dampers with the right...bachelor thesis 2019
 document

Kooij, Robert (author), Zegeling, André (author)In this paper we study the generalized Gause model, with a logistic growth rate for the prey in absence of the predator, a constant death rate for the predator and for several different classes of functional response, all nonanalytical. First we consider the piecewiselinear functional response of Holling type I, which essentially has a...journal article 2019
 document

Ivens, Mark (author)Reset controllers can outperform PID controllers and may introduce phase advantage compared to linear PID control. However, in general, reset controllers do not have the same steady state properties as linear controllers, like removing steady state errors. In case of model mismatches and disturbances, this may cause limit cycles (persisting...master thesis 2018
 document

Gaiko, V. (author), Vuik, Cornelis (author), Reijm, Huibert A.J. (author)In this paper, we study a multiparameter Liénard polynomial system carrying out its global bifurcation analysis. To control the global bifurcations of limit cycle in this systems, it is necessary to know the properties and combine the effects of all its field rotation parameters. It can be done by means of the development of our...journal article 2018
 document

Gaiko, Valery A. (author), Vuik, Cornelis (author)We complete the global bifurcation analysis of the LeslieGower system with the Allee effect which models the dynamics of the populations of predators and their prey in a given ecological or biomedical system. In particular, studying global bifurcations of limit cycles, we prove that such a system can have at most two limit cycles surrounding...journal article 2018
 document

Zegeling, A. (author), Kooij, Robert (author)In this paper we study the existence and uniqueness of limit cycles for socalled quadratic systems with a symmetrical solution: dx(t)/dt = P<sub>2</sub>(x, y) ≡ a<sub>00</sub>+ a<sub>10</sub>x + a<sub>01</sub>y + a<sub>20</sub>x<sup>2</sup>+ a<sub>11</sub>xy + a<sub>02</sub>y<sup>2</sup>dy(t)/dt = Q<sub>2</sub>(x, y) ≡ b<sub>00</sub>+ b<sub...journal article 2018
 document

van Rooij, A.C.L.M. (author)Aerodynamic nonlinearities, such as shock waves, boundary layer separation or boundary layer transition, may cause an amplitude limitation of the oscillations induced by the fluid flow around a structure. These aeroelastic limitcycle oscillations (LCOs) resulting from aerodynamic nonlinearities have been studied numerically in this PhD thesis...doctoral thesis 2017
 document

Gaiko, V. (author), Ginoux, JeanMarc (author), Vuik, Cornelis (author)We carry out the global bifurcation analysis of the Kukles system representing a planar polynomial dynamical system with arbitrary linear and cubic righthand sides and having an antisaddle at the origin. Using the <br/>Wintner–Perko termination principle of multiple limit cycles, we solve the problem on the maximum number and distribution of...journal article 2017
 document
 Bernhammer, L.O. (author), Navalkar, S.T. (author), Sodja, J. (author), De Breuker, R. (author), Karpel, M (author) journal article 2017
 document

Feirstein, D.S. (author)Reinforcement learning is a powerful tool to derive controllers for systems where no models are available. Particularly policy search algorithms are suitable for complex systems, to keep learning time manageable and account for continuous state and action spaces. However, these algorithms demand more insight into the system to choose a suitable...master thesis 2016
Pages
 1
 2