311 citations · 859 across the 33 of their papers we have counts for
33 papers
Comparing Model-based Control Strategies for a Quadruple Tank System: Decentralized PID, LMPC, and NMPC
Anders H. D. Christensen, Tobias K. S. Ritschel, Jan Lorenz Svensen +3
This paper compares the performance of a decentralized proportional-integral-derivative (PID) controller, a linear model predictive controller (LMPC), and a nonlinear model predict…
Mathematical meal models for simulation of human metabolism
Tobias K. S. Ritschel, Asbjørn Thode Reenberg, Peter Emil Carstensen +2
We present and critically discuss five commonly used mathematical models of the meal glucose rate of appearance in humans. Such models are key to simulation of the metabolism in he…
Quantitative modeling and simulation of biochemical processes in the human body
Jacob Bendsen, Peter Emil Carstensen, Asbjørn Thode Reenberg +2
We present a whole-body model of human metabolism that utilizes a system of organs and blood vessels to simulate the enzymatic reactions. The model focuses on key organs, including…
Dynamics of electronic states in the insulating Intermediate surface phase of 1T-TaS
Jingwei Dong, Weiyan Qi, Dongbin Shin +14
This article reports a comparative study of bulk and surface properties in the transition metal dichalcogenide 1T-TaS. When heating the sample, the surface displays an intermed…
A Newton-like Method based on Model Reduction Techniques for Implicit Numerical Methods
Tobias K. S. Ritschel
In this paper, we present a Newton-like method based on model reduction techniques, which can be used in implicit numerical methods for approximating the solution to ordinary diffe…
Modeling, scientific computing and optimal control for renewable energy systems with storage
Nicola Cantisani, Tobias K. S. Ritschel, Christian A. Thilker +2
This paper presents models for renewable energy systems with storage, and considers its optimal operation. We model and simulate wind and solar power production using stochastic di…
Model-based control algorithms for the quadruple tank system: An experimental comparison
Anders H. D. Andersen, Tobias K. S. Ritschel, Steen Hørsholt +2
We compare the performance of proportional-integral-derivative (PID) control, linear model predictive control (LMPC), and nonlinear model predictive control (NMPC) for a physical s…
State Estimation for Continuous-Discrete-Time Nonlinear Stochastic Systems
Marcus Krogh Nielsen, Tobias K. S. Ritschel, Ib Christensen +4
State estimation incorporates the feedback in optimization based advanced process control systems and is very important for the performance of model predictive control. We describe…
Estimating a Personalized Basal Insulin Dose from Short-Term Closed-Loop Data in Type 2 Diabetes
Sarah Ellinor Engell, Tinna Björk Aradóttir, Tobias K. S. Ritschel +2
In type 2 diabetes (T2D) treatment, finding a safe and effective basal insulin dose is a challenge. The dose-response is highly individual and to ensure safety, people with T2D tit…
Electronic dispersion, correlations and stacking in the photoexcited state of 1T-TaS
Jingwei Dong, Dongbin Shin, Ernest Pastor +11
Here we perform angle and time-resolved photoelectron spectroscopy on the commensurate Charge Density Wave (CDW) phase of 1T-TaS. Data with different probe pulse polarization a…
Pressure-tuning of -RuCl towards the ideal Kitaev-limit
Quirin Stahl, Tobias Ritschel, Gaston Garbarino +4
We report the discovery of an intriguing pressure-driven phase transformation in the layered Kitaev-material -RuCl. By analyzing both the Bragg scattering as well as the dif…
State Estimation Methods for Continuous-Discrete Nonlinear Systems involving Stochastic Differential Equations
Marcus Krogh Nielsen, Tobias K. S. Ritschel, Ib Christensen +4
In this work, we present methods for state estimation in continuous-discrete nonlinear systems involving stochastic differential equations. We present the extended Kalman filter, t…
A whole-body multi-scale mathematical model for dynamic simulation of the metabolism in man
Peter Emil Carstensen, Jacob Bendsen, Asbjørn Thode Reenberg +2
We propose a whole-body model of the metabolism in man as well as a generalized approach for modeling metabolic networks. Using this approach, we are able to write a large metaboli…
Large-scale Virtual Clinical Trials of Closed-loop Treatments for People with Type 1 Diabetes
Tobias K. S. Ritschel, Asbjørn Thode Reenberg, John Bagterp Jørgensen
We propose a virtual clinical trial for assessing the safety and efficacy of closed-loop diabetes treatments prior to an actual clinical trial. Such virtual trials enable rapid and…
Nonlinear Model Predictive Control and System Identification for a Dual-hormone Artificial Pancreas
Asbjørn Thode Reenberg, Tobias K. S. Ritschel, Emilie B. Lindkvist +5
In this work, we present a switching nonlinear model predictive control (NMPC) algorithm for a dual-hormone artificial pancreas (AP), and we use maximum likelihood estimation (MLE)…
High-performance Uncertainty Quantification in Large-scale Virtual Clinical Trials of Closed-loop Diabetes Treatment
Asbjørn Thode Reenberg, Tobias K. S. Ritschel, Bernd Dammann +1
In this paper, we propose a virtual clinical trial for assessing the performance and identifying risks in closed-loop diabetes treatments. Virtual clinical trials enable fast and r…
A one-size-fits-all artificial pancreas for people with type 1 diabetes based on physiological insight and feedback control
Tobias K. S. Ritschel, Asbjørn Thode Reenberg, Emilie B. Lindkvist +6
We propose a model-free artificial pancreas (AP) for people with type 1 diabetes. The algorithmic parameters are tuned to a virtual population of 1,000,000 individuals, and the AP…
Temperature-driven reorganization of electronic order in CsVSb
Q. Stahl, D. Chen, T. Ritschel +3
We report a temperature dependent x-ray diffraction study of the electronic ordering instabilities in the kagome material CsVSb. Our measurements between 10 K and 120 K rev…
Model Predictive Control Tailored to Epidemic Models
Philipp Sauerteig, Willem Esterhuizen, Mitsuru Wilson +3
We propose a model predictive control (MPC) approach for minimising the social distancing and quarantine measures during a pandemic while maintaining a hard infection cap. To this…
Hidden Charge Order in an Iron Oxide Square-Lattice Compound
Jung-Hwa Kim, Darren C. Peets, Manfred Reehuis +14
Since the discovery of charge disproportionation in the FeO square-lattice compound SrFeO by Mössbauer spectroscopy more than fifty years ago, the spatial ordering…
How to coordinate vaccination and social distancing to mitigate SARS-CoV-2 outbreaks
Sara Grundel, Stefan Heyder, Thomas Hotz +3
Most countries have started vaccinating people against COVID-19. However, due to limited production capacities and logistical challenges it will take months/years until herd immuni…
Fermi surface chirality induced in a TaSe monosheet formed by a Ta/ BiSe interface reaction
Andrey Polyakov, Katayoon Mohseni, Roberto Felici +9
Spin-momentum locking in topological insulators and materials with Rashba-type interactions is an extremely attractive feature for novel spintronic devices and is therefore under i…
How much testing and social distancing is required to control COVID-19? Some insight based on an age-differentiated compartmental model
Sara Grundel, Stefan Heyder, Thomas Hotz +3
In this paper, we provide insights on how much testing and social distancing is required to control COVID-19. To this end, we develop a compartmental model that accounts for key as…
Nonlinear model reduction of dynamical power grid models using quadratization and balanced truncation
Tobias K. S. Ritschel, Frances Weiß, Manuel Baumann +1
In this work, we present a nonlinear model reduction approach for reducing two commonly used nonlinear dynamical models of power grids: the effective network (EN) model and the syn…