no code implementations • 15 Mar 2024 • Victor Molnö, Henrik Sandberg
In this work, we contribute to the development of such a theory by introducing an example water network structure with parallel pipes that is tractable for analytical treatment.
no code implementations • 20 Oct 2023 • Daniel Selvaratnam, Amritam Das, Henrik Sandberg
Motivated by the need to localise faults along electrical power lines, this paper adopts a frequency-domain approach to parameter estimation for an infinite-dimensional linear dynamical system with one spatial variable.
no code implementations • 18 Apr 2023 • Junsoo Kim, Jin Gyu Lee, Henrik Sandberg, Karl H. Johansson
As a result, although a portion of measurements are compromised, they can be locally identified and excluded from the state estimation, and thus the true state can be recovered.
no code implementations • 27 Mar 2023 • Bruce D. Lee, Ingvar Ziemann, Anastasios Tsiamis, Henrik Sandberg, Nikolai Matni
We present a local minimax lower bound on the excess cost of designing a linear-quadratic controller from offline data.
no code implementations • 23 Jul 2022 • Sebin Gracy, Philip E. Paré, Ji Liu, Henrik Sandberg, Carolyn L. Beck, Karl Henrik Johansson, Tamer Başar
We establish a sufficient condition and multiple necessary conditions for local exponential convergence to the boundary equilibrium (i. e., one virus persists, the other one dies out) of each virus.
no code implementations • 14 Jun 2022 • Ingvar Ziemann, Anastasios Tsiamis, Henrik Sandberg, Nikolai Matni
We study stochastic policy gradient methods from the perspective of control-theoretic limitations.
no code implementations • 1 Apr 2022 • Hampei Sasahara, György Dán, Saurabh Amin, Henrik Sandberg
Each player faces the cost of delayed delivery (due to charging requirements of EVs) and a pollution cost levied on the ICEVs.
no code implementations • 31 Mar 2022 • Ludvig Lindstrom, Sebin Gracy, Sindri Magnusson, Henrik Sandberg
Finally, assuming the existence of a single leak, for a network comprising of more than one pipe and assuming that the network has a tree structure, we provide a systematic procedure for determining the leak location, the leak exponent, and the leak constant
no code implementations • 31 Mar 2022 • Hampei Sasahara, Takashi Tanaka, Henrik Sandberg
We address the attack impact evaluation problem for control system security.
no code implementations • 16 Feb 2022 • Ingvar Ziemann, Henrik Sandberg, Nikolai Matni
Given a single trajectory of a dynamical system, we analyze the performance of the nonparametric least squares estimator (LSE).
no code implementations • 5 Jan 2022 • Ingvar Ziemann, Henrik Sandberg
TWe establish regret lower bounds for adaptively controlling an unknown linear Gaussian system with quadratic costs.
no code implementations • 12 Nov 2021 • David Umsonst, Serkan Sarıtaş, György Dán, Henrik Sandberg
We present a moving target defense strategy to reduce the impact of stealthy sensor attacks on feedback systems.
no code implementations • 5 Nov 2021 • David Umsonst, Henrik Sandberg
In this work, we evaluate theoretical results on the feasibility of, the worst-case impact of, and defense mechanisms against a stealthy sensor attack in an experimental setup.
no code implementations • 20 Sep 2021 • Philip E. Pare, Axel Janson, Sebin Gracy, Ji Liu, Henrik Sandberg, Karl H. Johansson
We develop a layered networked spread model for a susceptible-infected-susceptible (SIS) pathogen-borne disease spreading over a human contact network and an infrastructure network, and refer to it as a layered networked susceptible-infected-water-susceptible (SIWS) model.
1 code implementation • 25 May 2021 • David Umsonst, Justin Ruths, Henrik Sandberg
A detector threshold that provides an acceptable false alarm rate is equivalent to a specific quantile of the detector output distribution.
no code implementations • 22 May 2021 • Ehsan Nekouei, Henrik Sandberg, Mikael Skoglund, Karl H. Johansson
To ensure parameter privacy, we propose a filter design framework which consists of two components: a randomizer and a nonlinear transformation.
no code implementations • 10 May 2021 • Jianqi Chen, Jieqiang Wei, Wei Chen, Henrik Sandberg, Karl H. Johansson, Jie Chen
Undetectable attacks are an important class of malicious attacks threatening the security of cyber-physical systems, which can modify a system's state but leave the system output measurements unaffected, and hence cannot be detected from the output.
no code implementations • 24 Mar 2021 • Hampei Sasahara, Henrik Sandberg
This study investigates general model-based incident handler's asymptotic behaviors in time against cyber attacks to control systems.
1 code implementation • 26 Jan 2021 • Amr Alanwar, Alexander Berndt, Karl Henrik Johansson, Henrik Sandberg
We propose a method to perform set-based state estimation of an unknown dynamical linear system using a data-driven set propagation function.
no code implementations • 1 Jan 2021 • Ezgi Korkmaz, Henrik Sandberg, Gyorgy Dan
Adversarial attacks against deep neural networks have been widely studied.
no code implementations • 18 Nov 2020 • Ingvar Ziemann, Henrik Sandberg
After defining the intrinsic notion of an uninformative optimal policy in terms of a singularity condition for Fisher information we obtain local minimax regret lower bounds for such uninformative instances of LQR by appealing to van Trees' inequality (Bayesian Cram\'er-Rao) and a representation of regret in terms of a quadratic form (Bellman error).
no code implementations • 11 Nov 2020 • Martin Lindström, Hampei Sasahara, Xingkang He, Henrik Sandberg, Karl Henrik Johansson
We study the worst-case attack strategy of a power injection attack against the physical layer of a smart distribution grid with a high penetration of photovoltaic resources.
1 code implementation • 19 Oct 2020 • Amr Alanwar, Victor Gassmann, Xingkang He, Hazem Said, Henrik Sandberg, Karl Henrik Johansson, Matthias Althoff
The set-based estimation has gained a lot of attention due to its ability to guarantee state enclosures for safety-critical systems.
Cryptography and Security Robotics
no code implementations • 23 Sep 2020 • Hampei Sasahara, Takayuki Ishizaki, Jun-ichi Imura, Henrik Sandberg
In accordance with the disconnection, the equipped attack detection unit should be reconfigured to maintain its detection capability.
no code implementations • 11 Apr 2020 • Xingkang He, Xiaoqiang Ren, Henrik Sandberg, Karl H. Johansson
The resilience of the secured filter with detection is verified by an explicit relationship between the upper bound of the estimation error and the number of detected attacked sensors.
no code implementations • 8 Jan 2020 • David Umsonst, Henrik Sandberg
We derive conditions for when the attacker is able to perfectly estimate the controller's state.