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Experiment design for impulse response identification with signal matrix models
(2021)IFACPapersOnLine ~ 19th IFAC Symposium on System Identification, SYSID 2021This paper formulates an input design approach for truncated infinite impulse response identification in the context of implicit model representations recently used as basis for datadriven simulation and control approaches. Precisely, the considered model consists of a linear combination of the columns of a data (or signal) matrix. An optimal combination for the case of noisy data was recently proposed using a maximum likelihood approach, ...Conference Paper 
RF pulse flattening in the SwissFEL facility based on modelfree iterative learning control
(2015)Proceedings of the 36th International Free Electron Laser Conference (FEL2014)This paper introduces an iterative approach to producing flattopped radio frequency (RF) pulses for driving the pulsed linear accelerators in the Swiss free electron laser (SwissFEL). The method is based on modelfree iterative learning control which iteratively updates the input pulse shape in order to generate the desired amplitude and phase pulses at the output of the RF system. The method has been successfully applied to the klystron ...Conference Paper 
Modelbased klystron linearization in the SwissFEL test facility
(2015)Proceedings of the 36th International Free Electron Laser Conference (FEL2014)An automatic procedure is developed to provide the optimal operating point of a klystron. Since klystrons are nonlinear with respect to the input amplitude, a modelbased amplitude controller is introduced which uses the klystron characteristic curves to obtain the appropriate high voltage power supply setting and amplitude, such that the operating point is close to the saturation. An advantage of the proposed design is that the overall ...Conference Paper 
Robust adaptive model predictive building climate control
(2017)IFACPapersOnLine ~ 20th IFAC World Congress. ProceedingsModel Predictive Control (MPC) is a promising algorithm for building climate control. However, the construction of an accurate building model is very challenging since identification experiments on buildings are, due to time and usage constraints, difficult to conduct and the construction data are often only known approximately. This paper proposes the use of a recently developed robust, adaptive MPC as a possible solution for handling ...Conference Paper 
BeamBased Power Distribution Over Multiple Klystrons in a Linear Accelerator
(2015)Proceedings of the 6th International Particle Accelerator Conference (IPAC 15)A linear accelerator including several klystron driver RF stations can be viewed as a single virtual RF station with a certain accelerating RF voltage (in amplitude and phase). This paper develops an optimization scheme that, for a specified beam energy gain, determines the klystrons output powers and the modulators high voltages optimally. The algorithm employs the klystron nonlinear static characteristics curves to calculate the input ...Conference Paper 
Pulse Compressor Phase and Amplitude Modulation Based on Iterative Learning Control
(2015)Proceedings of the 6th International Particle Accelerator Conference (IPAC 15)This paper presents an alternative way to produce flattopped RF pulses at the pulse compressor output. Flattopped RF pulses are suitable for multibunch operation where it is often required that beams experience the same accelerating gradient. Moreover, the energy gain, in this case, is less sensitive to timing jitters. The proposed approach is based on Iterative Learning Control technique, which iteratively updates the input waveforms, ...Conference Paper 
On the optimal control problem for a class of monotone bilinear systems
(2016)Proceedings of the 22nd International Symposium on Mathematical Theory of Networks and SystemsWe consider a class of positive systems in which the control signal enters bilinearly with the state. Such dynamics arise naturally, for example, from modeling the evolutionary dynamics of HIV in the presence of drug therapy. For this class of system, we formulate an infinite horizon optimal control problem and show that the optimal control signal is constant over time. We further extend our results to the case of uncertain dynamics and ...Conference Paper 
Nonlinear functional characterizations of uncertainty in model validation
(2002)IFAC Proceedings Volumes ~ Proceedings of the 15th IFAC World CongressModel validation provides a useful means of assessing the ability of a model to account for a specific experimental observation, and has application to modeling, identifi cation and fault detection. In this paper we consider a new approach to the linear fractional transformation (LFT) model validation problem by deploying quadratic functionals, and more generally nonlinear functionals, to specify noise and dynamical perturbation sets. ...Conference Paper 
Asynchronous switching decentralized controllers for spacecraft formations
(2004)IFAC Proceedings Volumes ~ Automatic control in aerospace 2004The spacecraft formation control design problem is specified in terms of the relative positions of all spacecraft in the formation. Each spacecraft controller requires only a subset of the formation relative positions, and can switch asynchronously between many such information subsets, allowing it to replace measured information by information communicated from other spacecraft. A two dimensional simulation example is used to illustrate ...Conference Paper 
Modeling, Identification and Control of Building Thermal Systems
(2014)Proceedings of the COLEB 2014 Workshop: Computational Optimisation of LowEnergy BuildingsIn this paper we report on our work in the past years on model predictive control of office buildings with focus on experimental applications and the modeling of buildings.Conference Paper