Titel Deelnemers "Umbilical properties of spacelike co-dimension two submanifolds" "Nastassja Cipriani, José Senovilla, Joeri Van der Veken" "A procedure for the extraction of a nonlinear microwave GaN FET model" "Gustavo Avolio, Valeria Vadalà, Iltcho Angelov, Antonio Raffo, Mauro Marchetti, Giorgio Vannini, Dominique Schreurs" "In this paper, we describe an extraction procedure of nonlinear models for microwave field-effect transistor (FET). We use a nonlinear model available in commercial CAD tools, and we extract the parameters by combining direct extraction and numerical optimization. We determine a first estimate of the model parameters by few DC and S-parameter measurements. Next, we refine the parameters by optimization against low-frequency and high-frequency vector-calibrated large-signal measurements gathered with a Large-Signal-Network Analyzer (LSNA). As case study we consider a 0.25 × 200 µm2 GaN FET on SiC for power amplifier applications. Ultimately, we want to show that a good accuracy level can be achieved while minimizing the extraction effort and that an accurate model can be built and suitably tailored depending on the final application." "Open Problems in Hash Function Security" "Elena Andreeva, Bart Mennink, Bart Preneel" "Paving over arbitrary MASAs in von Neumann algebras" "Sorin Popa, Stefaan Vaes" "A Gaussian quadrature rule for oscillatory integrals on a bounded interval" "Andreas Asheim, Alfredo Deaño Cabrera, Daan Huybrechs, Haiyong Wang" "Noise reduction in coarse bifurcation analysis of stochastic agent-based models: an example of consumer lock-in" "Daniele Avitabile, Rebecca Hoyle, Giovanni Samaey" "A Riemannian geometry with complete geodesics for the set of positive semidefinite matrices of fixed rank" "Bart Vandereycken, P-A Absil, Stefan Vandewalle" "We present a homogeneous space geometry for the manifold of symmetric positive semidefinite matrices of fixed rank. The total space is a connected part of the general linear group endowed with its natural right-invariant metric and the metric on the homogeneous space is chosen such that the quotient space is the image of a Riemannian submersion from the total space. As a result, we obtain complete geodesics that are the image of certain geodesics on the general linear group. We derive in addition an efficient closed-form expression for these geodesics. Furthermore, we isometrically embed the abstract quotient space into the space of real matrices. This allows us to interpret the vector fields, the metric and the geodesics in terms of concrete matrices. Finally, we compare our geometry with some other geometries in the literature. In particular, we show how other geodesics and their approximations relate to ours.}{homogeneous space; complete geodesic; positive semidefinite cone; low rank matrix; quotient manifold; embedded submanifold." "Lorentzian Affine Hypersurfaces with Parallel Cubic Form" "Zejun Hu, Cece Li, Haizhong Li, Luc Vrancken" "A SPLITTING PROXIMAL POINT METHOD FOR NASH-COURNOT EQUILIBRIUM MODELS INVOLVING NONCONVEX COST FUNCTIONS" "Quoc Tran Dinh" "Asymptotic analysis of numerical steepest descent with path approximations" "Andreas Asheim, Daan Huybrechs"