Visible to the public Biblio

Filters: Author is Vamvoudakis, Kyriakos G.  [Clear All Filters]
2022-12-09
Zhai, Lijing, Vamvoudakis, Kyriakos G., Hugues, Jérôme.  2022.  A Graph-Theoretic Security Index Based on Undetectability for Cyber-Physical Systems. 2022 American Control Conference (ACC). :1479—1484.
In this paper, we investigate the conditions for the existence of dynamically undetectable attacks and perfectly undetectable attacks. Then we provide a quantitative measure on the security for discrete-time linear time-invariant (LTI) systems under both actuator and sensor attacks based on undetectability. Finally, the computation of proposed security index is reduced to a min-cut problem for the structured systems by graph theory. Numerical examples are provided to illustrate the theoretical results.
2020-10-05
Kanellopoulos, Aris, Vamvoudakis, Kyriakos G., Gupta, Vijay.  2019.  Decentralized Verification for Dissipativity of Cascade Interconnected Systems. 2019 IEEE 58th Conference on Decision and Control (CDC). :3629—3634.

In this paper, we consider the problem of decentralized verification for large-scale cascade interconnections of linear subsystems such that dissipativity properties of the overall system are guaranteed with minimum knowledge of the dynamics. In order to achieve compositionality, we distribute the verification process among the individual subsystems, which utilize limited information received locally from their immediate neighbors. Furthermore, to obviate the need for full knowledge of the subsystem parameters, each decentralized verification rule employs a model-free learning structure; a reinforcement learning algorithm that allows for online evaluation of the appropriate storage function that can be used to verify dissipativity of the system up to that point. Finally, we show how the interconnection can be extended by adding learning-enabled subsystems while ensuring dissipativity.