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作者：Keroglou, Christoforos; Lafortune, Stephane
作者单位：University of Michigan System; University of Michigan
摘要：We investigate the enforcement of opacity, an information-flow privacy property, using insertion sequences that modify the output of the system by event insertions. Previous work considered the problem of enforcing the opacity under the assumption that the insertion functions were based on the observed system strings. Now, we investigate the more powerful method of insertion sequences based on the exact system states and events. In this case, the insertion function would be embedded into the s...
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作者：Li, Tongxiang; Chen, Bo; Yu, Li; Zhang, Wen-An
作者单位：Zhejiang University of Technology; Zhejiang University of Technology
摘要：An active security control approach is developed in this article for cyber-physical systems (CPSs) under denial-of-service (DoS) attacks, where DoS attacks exist in both the sensor-to-controller (S-C) channel and the controller-to-actuator (C-A) channel. Due to the cost constraints of attacks, it is reasonable to consider that the number of maximum continuous DoS attacks in both the S-C and the C-A channels is bounded. Then, to defend the two-channel DoS attacks, an active security control str...
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作者：Ma, Hong-Jun; Xu, Lin-Xing
作者单位：Northeastern University - China; Northeastern University - China
摘要：This article addresses the decentralized tracking control problem for a class of strong interconnected nonlinear systems with actuator faults. The considered interconnections are allowed to be dominated by some bounding functions, which are linear growth in the status of all subsystems. First, an adaptive high-gain technique is introduced to deal with the unknown strong interconnections. Then, a group of fault-tolerant controllers is designed to adaptively compensate for the effects of the act...
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作者：Bujarbaruah, Monimoy; Zhang, Xiaojing; Tanaskovic, Marko; Borrelli, Francesco
作者单位：University of California System; University of California Berkeley
摘要：This article deals with the problem of formulating an adaptive model-predictive control strategy for constrained uncertain systems. We consider a linear system in the presence of bounded time-varying additive uncertainty. The uncertainty is decoupled as the sum of a process noise with known bounds and a time-varying offset that we wish to identify. The time-varying offset uncertainty is assumed unknown pointwise in time. Its domain, called the feasible parameter set, and its maximum rate of ch...
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作者：Griffioen, Paul; Weerakkody, Sean; Sinopoli, Bruno
作者单位：Carnegie Mellon University; Washington University (WUSTL)
摘要：This article considers the design and analysis of multiple moving target defenses for recognizing and isolating attacks on cyber-physical systems. We consider attackers who perform integrity attacks on some set of sensors and actuators in a control system. In such cases, it has been shown that a model aware adversary can carefully design attack vectors to bypass bad data detection and identification filters while causing damage to the control system. To counter such an attacker, we propose the...
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作者：Rey, Felix; Hokayem, Peter; Lygeros, John
作者单位：Boston Consulting Group (BCG); Swiss Federal Institutes of Technology Domain; ETH Zurich
摘要：We consider a model predictive control setting, where we use the alternating direction method of multipliers (ADMM) to exploit problem structure. We take advantage of interacting components in the controlled system by decomposing its dynamics with virtual subsystems and virtual inputs. We introduce subsystem-individual penalty parameters together with optimal selection techniques. Further, we propose a novel measure of system structure, which we call separation tendency. For a sufficiently str...
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作者：Ye, Lintao; Woodford, Nathaniel; Roy, Sandip; Sundaram, Shreyas
作者单位：Purdue University System; Purdue University; Washington State University
摘要：Given a linear dynamical system affected by stochastic noise, we consider the problem of selecting an optimal set of sensors (at design time) to minimize the trace of the steady-state a priori or a posteriori error covariance of the Kalman filter, subject to certain selection budget constraints. We show the fundamental result that there is no polynomial-time constant-factor approximation algorithm for this problem. This contrasts with other classes of sensor selection problems studied in the l...
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作者：Ouyang, Yi; Asghari, Seyed Mohammad; Nayyar, Ashutosh
作者单位：University of Southern California
摘要：We consider a decentralized networked control system (DNCS) consisting of a remote controller and a collection of linear plants, each associated with a local controller. Each local controller directly observes the state of its colocated plant and can inform the remote controller of the plant's state through an unreliable uplink channel. The downlink channels from the remote controller to local controllers were assumed to be perfect. The objective of the local controllers and the remote control...
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作者：Yin, Xiang; Zamani, Majid; Liu, Siyuan
作者单位：Shanghai Jiao Tong University; Shanghai Jiao Tong University; University of Colorado System; University of Colorado Boulder; University of Munich; Technical University of Munich
摘要：Opacity is an important information-flow security property in the analysis of cyber-physical systems. It captures the plausible deniability of the system's secret behavior in the presence of an intruder that may access the information flow. Existing works on opacity only consider nonmetric systems by assuming that the intruder can always distinguish between two different outputs precisely. In this article, we extend the concept of opacity to systems whose output sets are equipped with metrics....
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作者：Ferrara, Antonella; Incremona, Gian Paolo
作者单位：University of Pavia; Polytechnic University of Milan
摘要：In this article, a novel second order sliding mode control strategy is proposed for relative-degree-2 nonlinear uncertain single- input-single-output (SISO) systems. To design the strategy, the phase portrait of the second order system in normal form associated with the formulated sliding mode control problem is studied. A sliding surface switching between arcs of parabolas is conceived to ensure the convergence in a predefined-time to the desired second order sliding mode. Lyapunov-based anal...
