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Carrier-wave Rabi flopping signatures in high-order harmonic generation
(2015)Journal of Physics: Conference SeriesWe present theoretical investigations of carrier-wave Rabi flopping (CWRF) in real atoms by studying high-order harmonic generation in alkali species. We concentrate on the features of the third harmonic of Na and K atoms. For pulse areas of 2π and Na atoms, a characteristic unique peak appears, which, after analyzing the ground state population, we correlate it with the conventional Rabi flopping. On the other hand, for larger pulse areas ...Conference Paper -
Benchmarking of data predictive control in a real-life apartment during heating season
(2021)Journal of Physics: Conference SeriesModel Predictive Control is an energy efficient climate control strategy in buildings. However, the effort associated with physics-based modelling seems to prevent widespread application in residential buildings. Applying machine-learning algorithms on historical data promises efficient generation of predictive models for control. In a recent experimental study, Data Predictive Control based on random forests and linear models outperformed ...Conference Paper -
Derivation and analysis of the analytical velocity and vortex stretching expressions for an O(N log N)-FMM
(2016)Journal of Physics: Conference SeriesIn the current paper, a method for deriving the analytical expressions for the velocity and vortex stretching terms as a function of the spherical multipole expansion approximation of the vector potential is presented. These terms are essential in the context of 3D Lagrangian vortex particle methods combined with fast summation techniques. The convergence and computational efficiency of this approach is assessed in the framework of an O(N ...Conference Paper -
Unsupervised Clustering of Eye Tracking Data
(2018)Spatial Big Data and Machine Learning in GIScience, Workshop at GIScience 2018The reading behavior on maps can strongly vary with factors such as background knowledge, mental model, task or the visual design of a map. Therefore, in cartography, eye tracking experiments have a long tradition to foster the visual attention. In this work-in-progress, we use an unsupervised machine learning pipeline for clustering eye tracking data. In particular, we focus on methods that help to validate and evaluate the clustering ...Conference Paper -
The next generation of laser spectroscopy experiments using light muonic atoms
(2018)Journal of Physics: Conference SeriesPrecision spectroscopy of light muonic atoms provides unique information about the atomic and nuclear structure of these systems and thus represents a way to access fundamental interactions, properties and constants. One application comprises the determination of absolute nuclear charge radii with unprecedented accuracy from measurements of the 2S - 2P Lamb shift. Here, we review recent results of nuclear charge radii extracted from muonic ...Conference Paper -
Bayesian Optimisation for Fast and Safe Parameter Tuning of SwissFEL
(2019)FEL2019, Proceedings of the 39th International Free-Electron Laser ConferenceParameter tuning is a notoriously time-consuming task in accelerator facilities. As tool for global optimization with noisy evaluations, Bayesian optimization was recently shown to outperform alternative methods. By learning a model of the underlying function using all available data, the next evaluation can be chosen carefully to find the optimum with as few steps as possible and without violating any safety constraints. However, the ...Conference Paper -
Beam Impact Experiment of 440GeV/p Protons on Superconducting Wires and Tapes in a Cryogenic Environment
(2019)Proceedings of the 10th International Particle Accelerator ConferenceThe superconducting magnets used in high energy particle accelerators such as CERN’s LHC can be impacted by the circulating beam in case of specific failure cases. This leads to interaction of the beam particles with the magnet components, like the superconducting coils, directly or via secondary particle showers. The interaction leads to energy deposition in the timescale of microseconds and induces large thermal gradients within the ...Conference Paper -
European drought trends
(2015)Proceedings of the International Association of Hydrological SciencesRecent climate projections suggest pronounced changes in European drought frequency. In the north, increased precipitation volumes are likely to reduce drought occurrence, whereas more frequent droughts are expected for southern Europe. To assess whether this pattern of changes in drought frequency can already be identified for the past decades, we analyse trends in a recently developed pan-European drought climatology that is based on ...Conference Paper -
On the time continuous evolution of the universe if time is discrete and irreversible in nature
(2019)Journal of Physics: Conference SeriesThe time evolution of the universe is usually mathematically described under a continuous time and thus time reversible. Here, the consequences of studying the evolution of a homogenous isotropic universe by time continuous reversible physics are studied if time is actually discrete and irreversible in nature. The discrete dynamical time concept of Lee and its continuous time limit to the continuous time case is applied to the Newtonian ...Conference Paper -
How to Evaluate the Quality of Airborne Laser-Scanning Data
(2004)International Archives of the Photogrammetry, Remote Sensing and Spatial Information SciencesThe discussion on the quality of digital elevation models form airborne laser scanner was dominated by the proof of vertical and horizontal accuracy. If the accuracy criteria were verified by ground control points, the evidence of high quality was produced. Based on experiences in projects for the Swiss Federal Office of Topography and according to the lidar requirements formulated by the US American ...Conference Paper