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  Subjects -> ELECTRONICS (Total: 207 journals)
Showing 1 - 200 of 277 Journals sorted alphabetically
ACS Applied Electronic Materials     Open Access   (Followers: 1)
Acta Electronica Malaysia     Open Access  
Advanced Materials Technologies     Hybrid Journal   (Followers: 2)
Advances in Biosensors and Bioelectronics     Open Access   (Followers: 6)
Advances in Electrical and Electronic Engineering     Open Access   (Followers: 5)
Advances in Electronics     Open Access   (Followers: 122)
Advances in Microelectronic Engineering     Open Access   (Followers: 12)
Advances in Power Electronics     Open Access   (Followers: 56)
Advancing Microelectronics     Hybrid Journal   (Followers: 2)
American Journal of Electrical and Electronic Engineering     Open Access   (Followers: 26)
Annals of Telecommunications     Hybrid Journal   (Followers: 6)
APSIPA Transactions on Signal and Information Processing     Open Access   (Followers: 8)
Archives of Electrical Engineering     Open Access   (Followers: 14)
Australian Journal of Electrical and Electronics Engineering     Hybrid Journal  
Automatika : Journal for Control, Measurement, Electronics, Computing and Communications     Open Access  
Batteries     Open Access   (Followers: 8)
Batteries & Supercaps     Hybrid Journal   (Followers: 5)
Bell Labs Technical Journal     Hybrid Journal   (Followers: 27)
Bioelectronics in Medicine     Hybrid Journal  
Canadian Journal of Remote Sensing     Full-text available via subscription   (Followers: 50)
China Communications     Full-text available via subscription   (Followers: 8)
Chinese Journal of Electronics     Open Access  
Circuits and Systems     Open Access   (Followers: 16)
Control Systems     Hybrid Journal   (Followers: 235)
e-Prime : Advances in Electrical Engineering, Electronics and Energy     Open Access   (Followers: 2)
ECTI Transactions on Electrical Engineering, Electronics, and Communications     Open Access   (Followers: 1)
Edu Elektrika Journal     Open Access   (Followers: 1)
Electronic Design     Partially Free   (Followers: 125)
Electronic Markets     Hybrid Journal   (Followers: 6)
Electronic Materials Letters     Hybrid Journal   (Followers: 4)
Electronics     Open Access   (Followers: 125)
Electronics and Communications in Japan     Hybrid Journal   (Followers: 8)
Electronics For You     Partially Free   (Followers: 114)
Electronics Letters     Open Access   (Followers: 25)
Elektronika ir Elektortechnika     Open Access  
Elkha : Jurnal Teknik Elektro     Open Access  
Emitor : Jurnal Teknik Elektro     Open Access  
Energy Storage     Hybrid Journal   (Followers: 2)
Energy Storage Materials     Full-text available via subscription   (Followers: 5)
EPE Journal : European Power Electronics and Drives     Hybrid Journal   (Followers: 3)
EPJ Quantum Technology     Open Access   (Followers: 2)
Facta Universitatis, Series : Electronics and Energetics     Open Access  
Foundations and Trends® in Communications and Information Theory     Full-text available via subscription   (Followers: 6)
Foundations and Trends® in Signal Processing     Full-text available via subscription   (Followers: 7)
Frontiers in Electronics     Open Access   (Followers: 1)
Frontiers of Optoelectronics     Hybrid Journal   (Followers: 1)
IACR Transactions on Symmetric Cryptology     Open Access  
IEEE Antennas and Propagation Magazine     Hybrid Journal   (Followers: 112)
IEEE Antennas and Wireless Propagation Letters     Hybrid Journal   (Followers: 88)
IEEE Embedded Systems Letters     Hybrid Journal   (Followers: 60)
IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology     Hybrid Journal  
IEEE Journal of Emerging and Selected Topics in Power Electronics     Hybrid Journal   (Followers: 52)
IEEE Journal of the Electron Devices Society     Open Access   (Followers: 8)
IEEE Journal on Exploratory Solid-State Computational Devices and Circuits     Hybrid Journal   (Followers: 2)
IEEE Letters on Electromagnetic Compatibility Practice and Applications     Hybrid Journal   (Followers: 1)
IEEE Magnetics Letters     Hybrid Journal   (Followers: 7)
IEEE Nanotechnology Magazine     Hybrid Journal   (Followers: 45)
IEEE Open Journal of Circuits and Systems     Open Access  
IEEE Open Journal of Industry Applications     Open Access  
IEEE Open Journal of the Industrial Electronics Society     Open Access  
IEEE Power Electronics Magazine     Full-text available via subscription   (Followers: 90)
IEEE Pulse     Hybrid Journal   (Followers: 5)
IEEE Reviews in Biomedical Engineering     Hybrid Journal   (Followers: 19)
IEEE Solid-State Circuits Letters     Hybrid Journal  
IEEE Solid-State Circuits Magazine     Hybrid Journal   (Followers: 11)
IEEE Transactions on Aerospace and Electronic Systems     Hybrid Journal   (Followers: 281)
IEEE Transactions on Antennas and Propagation     Full-text available via subscription   (Followers: 78)
IEEE Transactions on Automatic Control     Hybrid Journal   (Followers: 65)
IEEE Transactions on Autonomous Mental Development     Hybrid Journal   (Followers: 8)
IEEE Transactions on Biomedical Engineering     Hybrid Journal   (Followers: 35)
IEEE Transactions on Broadcasting     Hybrid Journal   (Followers: 11)
IEEE Transactions on Circuits and Systems for Video Technology     Hybrid Journal   (Followers: 31)
IEEE Transactions on Consumer Electronics     Hybrid Journal   (Followers: 45)
IEEE Transactions on Electron Devices     Hybrid Journal   (Followers: 18)
IEEE Transactions on Geoscience and Remote Sensing     Hybrid Journal   (Followers: 174)
IEEE Transactions on Haptics     Hybrid Journal   (Followers: 4)
IEEE Transactions on Industrial Electronics     Hybrid Journal   (Followers: 85)
IEEE Transactions on Industry Applications     Hybrid Journal   (Followers: 57)
IEEE Transactions on Information Theory     Hybrid Journal   (Followers: 27)
IEEE Transactions on Learning Technologies     Full-text available via subscription   (Followers: 12)
IEEE Transactions on Power Electronics     Hybrid Journal   (Followers: 87)
IEEE Transactions on Services Computing     Hybrid Journal   (Followers: 5)
IEEE Transactions on Signal and Information Processing over Networks     Hybrid Journal   (Followers: 14)
IEEE Transactions on Software Engineering     Hybrid Journal   (Followers: 84)
IEEE Women in Engineering Magazine     Hybrid Journal   (Followers: 11)
IEEE/OSA Journal of Optical Communications and Networking     Hybrid Journal   (Followers: 19)
IEICE - Transactions on Electronics     Full-text available via subscription   (Followers: 11)
IEICE - Transactions on Information and Systems     Full-text available via subscription   (Followers: 5)
IET Cyber-Physical Systems : Theory & Applications     Open Access   (Followers: 1)
IET Energy Systems Integration     Open Access   (Followers: 1)
IET Microwaves, Antennas & Propagation     Open Access   (Followers: 35)
IET Nanodielectrics     Open Access  
IET Power Electronics     Open Access   (Followers: 76)
IET Smart Grid     Open Access   (Followers: 2)
IET Wireless Sensor Systems     Open Access   (Followers: 17)
IETE Journal of Education     Open Access   (Followers: 3)
IETE Journal of Research     Open Access   (Followers: 10)
IETE Technical Review     Open Access   (Followers: 9)
IJEIS (Indonesian Journal of Electronics and Instrumentation Systems)     Open Access   (Followers: 3)
Industrial Technology Research Journal Phranakhon Rajabhat University     Open Access  
Informatik-Spektrum     Hybrid Journal   (Followers: 3)
Intelligent Transportation Systems Magazine, IEEE     Full-text available via subscription   (Followers: 12)
International Journal of Advanced Electronics and Communication Systems     Open Access   (Followers: 10)
International Journal of Advanced Research in Computer Science and Electronics Engineering     Open Access   (Followers: 14)
International Journal of Advances in Telecommunications, Electrotechnics, Signals and Systems     Open Access   (Followers: 12)
International Journal of Aerospace Innovations     Full-text available via subscription   (Followers: 23)
International Journal of Antennas and Propagation     Open Access   (Followers: 10)
International Journal of Applied Electronics in Physics & Robotics     Open Access   (Followers: 3)
International Journal of Computational Vision and Robotics     Hybrid Journal   (Followers: 5)
International Journal of Control     Hybrid Journal   (Followers: 13)
International Journal of Electronics     Hybrid Journal   (Followers: 7)
International Journal of Electronics and Telecommunications     Open Access   (Followers: 8)
International Journal of Granular Computing, Rough Sets and Intelligent Systems     Hybrid Journal   (Followers: 1)
International Journal of High Speed Electronics and Systems     Hybrid Journal  
International Journal of Hybrid Intelligence     Hybrid Journal   (Followers: 1)
International Journal of Image, Graphics and Signal Processing     Open Access   (Followers: 22)
International Journal of Microwave and Wireless Technologies     Hybrid Journal   (Followers: 16)
International Journal of Nanoscience     Hybrid Journal  
International Journal of Numerical Modelling: Electronic Networks, Devices and Fields     Hybrid Journal   (Followers: 4)
International Journal of Power Electronics     Hybrid Journal   (Followers: 30)
International Journal of Review in Electronics & Communication Engineering     Open Access   (Followers: 2)
International Journal of Sensors, Wireless Communications and Control     Hybrid Journal   (Followers: 13)
International Journal of Systems, Control and Communications     Hybrid Journal   (Followers: 6)
International Journal of Wireless and Microwave Technologies     Open Access   (Followers: 12)
International Transaction of Electrical and Computer Engineers System     Open Access   (Followers: 2)
JAREE (Journal on Advanced Research in Electrical Engineering)     Open Access  
Journal of Biosensors & Bioelectronics     Open Access   (Followers: 4)
Journal of Advanced Dielectrics     Open Access   (Followers: 1)
Journal of Artificial Intelligence     Open Access   (Followers: 18)
Journal of Circuits, Systems, and Computers     Hybrid Journal   (Followers: 4)
Journal of Computational Intelligence and Electronic Systems     Full-text available via subscription   (Followers: 1)
Journal of Electrical and Electronics Engineering Research     Open Access   (Followers: 41)
Journal of Electrical Engineering & Electronic Technology     Hybrid Journal   (Followers: 4)
Journal of Electromagnetic Analysis and Applications     Open Access   (Followers: 6)
Journal of Electromagnetic Waves and Applications     Hybrid Journal   (Followers: 10)
Journal of Electronic Science and Technology     Open Access  
Journal of Electronics (China)     Hybrid Journal   (Followers: 5)
Journal of Energy Storage     Full-text available via subscription   (Followers: 4)
Journal of Engineered Fibers and Fabrics     Open Access  
Journal of Field Robotics     Hybrid Journal   (Followers: 5)
Journal of Guidance, Control, and Dynamics     Hybrid Journal   (Followers: 165)
Journal of Information and Telecommunication     Open Access   (Followers: 2)
Journal of Intelligent Procedures in Electrical Technology     Open Access   (Followers: 2)
Journal of Low Power Electronics     Full-text available via subscription   (Followers: 14)
Journal of Low Power Electronics and Applications     Open Access   (Followers: 9)
Journal of Microelectronics and Electronic Packaging     Hybrid Journal   (Followers: 2)
Journal of Microwave Power and Electromagnetic Energy     Hybrid Journal   (Followers: 8)
Journal of Nuclear Cardiology     Hybrid Journal   (Followers: 1)
Journal of Optoelectronics Engineering     Open Access   (Followers: 4)
Journal of Power Electronics     Hybrid Journal   (Followers: 8)
Journal of Power Electronics & Power Systems     Full-text available via subscription   (Followers: 19)
Journal of Sensors     Open Access   (Followers: 25)
Jurnal Rekayasa Elektrika     Open Access  
Jurnal Teknik Elektro     Open Access  
Jurnal Teknologi Elektro     Open Access  
Kinetik : Game Technology, Information System, Computer Network, Computing, Electronics, and Control     Open Access   (Followers: 5)
Machine Learning with Applications     Full-text available via subscription   (Followers: 2)
Majalah Ilmiah Teknologi Elektro : Journal of Electrical Technology     Open Access   (Followers: 1)
Metrology and Measurement Systems     Open Access   (Followers: 8)
Microelectronics and Solid State Electronics     Open Access   (Followers: 27)
Nanotechnology, Science and Applications     Open Access   (Followers: 7)
Nature Electronics     Hybrid Journal   (Followers: 3)
Networks: an International Journal     Hybrid Journal   (Followers: 4)
npj Flexible Electronics     Open Access  
Open Electrical & Electronic Engineering Journal     Open Access   (Followers: 1)
Open Journal of Antennas and Propagation     Open Access   (Followers: 8)
Power Electronics and Drives     Open Access   (Followers: 2)
Problemy Peredachi Informatsii     Full-text available via subscription  
Progress in Quantum Electronics     Full-text available via subscription   (Followers: 8)
Radiophysics and Quantum Electronics     Hybrid Journal   (Followers: 2)
Research & Reviews : Journal of Embedded System & Applications     Full-text available via subscription   (Followers: 6)
Security and Communication Networks     Hybrid Journal   (Followers: 2)
Selected Topics in Applied Earth Observations and Remote Sensing, IEEE Journal of     Hybrid Journal   (Followers: 62)
Semiconductors and Semimetals     Full-text available via subscription   (Followers: 1)
Sensing and Imaging : An International Journal     Hybrid Journal   (Followers: 2)
Sensors International     Open Access   (Followers: 3)
Solid State Electronics Letters     Open Access  
Solid-State Electronics     Hybrid Journal   (Followers: 7)
Superconductivity     Full-text available via subscription   (Followers: 2)
Synthesis Lectures on Power Electronics     Full-text available via subscription   (Followers: 4)
Technical Report Electronics and Computer Engineering     Open Access  
Telematique     Open Access  
TELKOMNIKA (Telecommunication, Computing, Electronics and Control)     Open Access   (Followers: 2)
Transactions on Cryptographic Hardware and Embedded Systems     Open Access   (Followers: 1)
Transactions on Electrical and Electronic Materials     Hybrid Journal   (Followers: 2)
Universal Journal of Electrical and Electronic Engineering     Open Access   (Followers: 7)
Ural Radio Engineering Journal     Open Access   (Followers: 1)
Visión Electrónica : algo más que un estado sólido     Open Access  
Wireless and Mobile Technologies     Open Access   (Followers: 4)
Електротехніка і Електромеханіка     Open Access   (Followers: 1)

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Similar Journals
Journal Cover
IEEE Transactions on Automatic Control
Journal Prestige (SJR): 3.433
Citation Impact (citeScore): 6
Number of Followers: 65  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0018-9286
Published by IEEE Homepage  [228 journals]
  • IEEE Control Systems Society

    • Free pre-print version: Loading...

      Abstract: Presents a listing of the editorial board, board of governors, current staff, committee members, and/or society editors for this issue of the publication.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • IEEE Control Systems Society

    • Free pre-print version: Loading...

      Abstract: Presents a listing of the editorial board, board of governors, current staff, committee members, and/or society editors for this issue of the publication.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Modal-Based Nonlinear Model Predictive Control for 3-D Very Flexible
           Structures

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      Authors: Marc Artola;Andrew Wynn;Rafael Palacios;
      Pages: 2145 - 2160
      Abstract: In this article a novel nonlinear model predictive control (NMPC) scheme is derived, which is tailored to the underlying structure of the intrinsic description of geometrically exact nonlinear beams (in which velocities and strains are primary variables). This is an important class of partial differential equation (PDE) models whose behavior is fundamental to the performance of flexible structural systems (e.g., wind turbines, high-altitude long-endurance aircraft). Furthermore, this class contains the much-studied Euler–Bernoulli and Timoshenko beam models, but has significant additional complexity (to capture 3-D effects and arbitrarily large displacements) and requires explicit computation of rotations in the PDE dynamics to account for orientation-dependent forces. A challenge presented by this formulation is that uncontrollable modes necessarily appear in any finite dimensional approximation to the PDE dynamics. We show, however, that an NMPC scheme can be constructed in which the error introduced by the uncontrollable modes can be explicitly controlled. It is demonstrated that the asymptotic error can be made insignificant (from a practical perspective) using our NMPC scheme and excellent performance is obtained even when applied to a highly resolved numerical simulation of the PDEs. We also present a generalization of Kelvin–Voigt damping to the intrinsic description of geometrically exact beams. Finally, special emphasis is placed on constructing a framework suitable for real-time NMPC control, where the particular structure of the underlying PDEs is exploited to obtain both efficient finite-dimensional models and numerical schemes.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Improved Input-to-State Stability Analysis of Impulsive Stochastic Systems

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      Authors: Pengfei Wang;Wenya Guo;Huan Su;
      Pages: 2161 - 2174
      Abstract: This article is concerned with the input-to-state stability (ISS) and stochastic input-to-state stability (SISS) of impulsive stochastic nonlinear systems. By constructing a general SISS-Lyapunov function, which takes the exponential SISS-Lyapunov function as a special case, the ISS criteria are obtained, respectively, for destabilizing and stabilizing impulses. It should be stressed that we impose the average dwell-time (ADT) condition for destabilizing impulses and reverse average dwell-time (RADT) condition for stabilizing impulses to restrain the occurrence of impulses, which extends the fixed dwell-time condition in recent literature. Moreover, the ADT and RADT conditions in this article correspond to the average impulsive interval method in most existing results under the exponential ISS-Lyapunov condition. As a subsequent result, the ISS and SISS of impulsive stochastic interconnected systems on networks are also studied by the Lyapunov method and graph-theoretic technique. Finally, several illustrative examples together with their numerical simulations are provided to demonstrate the theoretical results.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • $mathrm{SO}(3)times+mathbb+{R}^{+n+}$ +and+Bayesian+Attitude+Estimation&rft.title=IEEE+Transactions+on+Automatic+Control&rft.issn=0018-9286&rft.date=2022&rft.volume=67&rft.spage=2175&rft.epage=2191&rft.aulast=Lee;&rft.aufirst=Weixin&rft.au=Weixin+Wang;Taeyoung+Lee;">Matrix Fisher–Gaussian Distribution on $mathrm{SO}(3)times mathbb {R}^{
           n }$ and Bayesian Attitude Estimation

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      Authors: Weixin Wang;Taeyoung Lee;
      Pages: 2175 - 2191
      Abstract: In this article, a new probability distribution, referred to as the matrix Fisher–Gaussian distribution, is proposed on the product manifold of three-dimensional special orthogonal group and Euclidean space. It is constructed by conditioning a multivariate Gaussian distribution from the ambient Euclidean space into the manifold, while imposing a certain geometric constraint on the correlation term to avoid over parameterization. The unique feature is that it may represent large uncertainties in attitudes, linear variables of an arbitrary dimension, and angular–linear correlations between them in a global fashion without singularities. Various stochastic properties and an approximate maximum likelihood estimator are developed. Furthermore, two methods are developed to propagate uncertainties through a stochastic differential equation representing attitude kinematics. Based on these, a Bayesian estimator is proposed to estimate the attitude and time-varying gyro bias concurrently. Numerical studies indicate that the proposed estimator provides more accurate estimates against the multiplicative extended Kalman filter and unscented Kalman filter for challenging cases.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Distributed Estimation and Control for Discrete Time-Varying
           Interconnected Systems

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      Authors: Bo Chen;Guoqiang Hu;Daniel W.C. Ho;Li Yu;
      Pages: 2192 - 2207
      Abstract: This article is concerned with the distributed estimation and control problem for time-varying large-scale interconnected systems (LISs). A novel decoupling strategy with sequential-structure is developed to deal with the interconnected terms in large-scale systems. Then, by using the idea of bounded recursive optimization, the local estimator gain for each subsystem is designed by solving self-relative convex optimization problem that is constructed based on each subsystem’s own information and its neighboring information. In this case, such design scheme of each local estimator can realize fully distributed estimation. Based on the distributed estimator, fully distributed estimator-based control method is also designed by constructing self-relative convex optimization problems. Notice that the solutions to the above-constructed convex optimization problems can be easily obtained by the standard software packages, and the computational complexity of each optimization problem is low even though the scale of interconnected systems is large. Furthermore, stability conditions are derived such that the designed distributed estimator and controller for time-varying LISs are asymptotically bounded. Finally, two illustrative examples are employed to show the effectiveness of the proposed methods.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Smart Greedy Distributed Energy Allocation: A Random Games Approach

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      Authors: Ilai Bistritz;Andrew Ward;Zhengyuan Zhou;Nicholas Bambos;
      Pages: 2208 - 2220
      Abstract: Consider a network of $N$ providers that each has a certain supply of energy and $B$ consumers that each has a certain demand. The efficiency of transmitting energy between providers and consumers is modeled using a weighted bipartite graph $G$. Our goal is to maximize the amount of utilized energy using a distributed algorithm that each provider runs locally. We propose a noncooperative energy-allocation game and adopt the best-response dynamics for this game as our distributed algorithm. We prove that the best-response dynamics converge in no more than $N$ steps to one of at most $N!$ pure Nash equilibria (NE) of our game. However, we show that these NE can be very inefficient. Remarkably, our algorithm avoids the inefficient NE and achieves asymptotically (in $B$) optimal performance in “almost all” games. The traditional game-theoretic analysis using a potential function does not explain this encouraging finding. To fill this gap, we analyze the best-response dynamics in a random game, where the network is generated using a random model for the graph $G$. We prove that the ratio between the utilized energy of our algorithm and that of the optimal solution converges to one in probability as $B$ increases (and $N$ is any function of $B$). Numerical simulations demonstrate that our asymptotic analysis is valid even for $B=10$ consumers. Our novel random games approach analytically explains why the performance of our algorithm is asymptotically optimal almost always despite the fact that bad NE may exist.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Distributed Derivative-Free Learning Method for Stochastic Optimization
           Over a Network With Sparse Activity

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      Authors: Wenjie Li;Mohamad Assaad;Shiqi Zheng;
      Pages: 2221 - 2236
      Abstract: This article addresses a distributed optimization problem in a communication network where nodes are active sporadically. Each active node applies some learning method to control its action to maximize the global utility function, which is defined as the sum of the local utility functions of active nodes. We deal with stochastic optimization problem with the setting that utility functions are disturbed by some nonadditive stochastic process. We consider a more challenging situation where the learning method has to be performed only based on a scalar approximation of the utility function, rather than its closed-form expression, so that the typical gradient descent method cannot be applied. This setting is quite realistic when the network is affected by some stochastic and time-varying process, and that each node cannot have the full knowledge of the network states. We propose a distributed optimization algorithm and prove its almost surely convergence to the optimum. Convergence rate is also derived with an additional assumption that the objective function is strongly concave. Numerical results are also presented to justify our claim.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Multiplayer Bandits: A Trekking Approach

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      Authors: Manjesh Kumar Hanawal;Sumit J. Darak;
      Pages: 2237 - 2252
      Abstract: In this article, we study stochastic multiarmed bandits with many players. The players do not know the number of players, cannot communicate with each other, and if multiple players select a common arm, they collide and none of them receive any reward. We consider the static scenario, where the number of players remains fixed, and the dynamic scenario, where the players enter and leave at any time. We provide algorithms based on a novel “trekking approach” that guarantees constant regret for the static case and sublinear regret for the dynamic case with high probability. The trekking approach eliminates the need to estimate the number of players resulting in fewer collisions and improved regret performance compared to state-of-the-art algorithms. We also develop an epoch-less algorithm that eliminates any requirement of time synchronization across the players provided each player can detect the presence of other players on an arm. We validate our theoretical guarantees using simulation-based and real testbed-based experiments.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Optimal Privacy-Aware Estimation

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      Authors: Ehsan Nekouei;Henrik Sandberg;Mikael Skoglund;Karl Henrik Johansson;
      Pages: 2253 - 2266
      Abstract: This article studies the design of an optimal privacy-aware estimator of a public random variable based on noisy measurements, which contain private information. The public variable carries also nonprivate information, but its estimate will be correlated with the private information due to the estimation process. The objective is to design an optimal estimator of the public random variable such that the leakage of private information, via the estimation process, is kept below a certain level. The privacy metric is defined as the discrete conditional entropy of the private variable given the output of the estimator. We show that the optimal privacy-aware estimator is the solution of a (possibly infinite-dimensional) convex optimization problem when the estimator has access to either the measurement or the measurement together with the private information. We study the optimal perfect-privacy estimation problem that ensures the estimate of the public variable is independent of the private information. A necessary and sufficient condition is derived guaranteeing that an estimator satisfies the perfect-privacy requirement. It is shown that the optimal perfect-privacy estimator is the solution of a linear optimization problem. A sufficient condition for its existence is derived. The impact of the distribution mismatch on the perfect-privacy condition is studied. Numerical examples are used to illustrate the privacy-accuracy tradeoff.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Adaptive Control Barrier Functions

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      Authors: Wei Xiao;Calin Belta;Christos G. Cassandras;
      Pages: 2267 - 2281
      Abstract: It has been shown that optimizing quadratic costs while stabilizing affine control systems to desired (sets of) states subject to state and control constraints can be reduced to a sequence of quadratic programs (QPs) by using control barrier functions (CBFs) and control Lyapunov functions (CLFs). In this article, we introduce adaptive CBFs (aCBFs) that can accommodate time-varying control bounds and noise in the system dynamics while also guaranteeing the feasibility of the QPs if the original quadratic cost optimization problem itself is feasible, which is a challenging problem in current approaches. We propose two different types of aCBFs: parameter-adaptive CBF (PACBF) and relaxation-adaptive CBF (RACBF). Central to aCBFs is the introduction of appropriate time-varying functions to modify the definition of a common CBF. These time-varying functions are treated as high-order CBFs with their own auxiliary dynamics, which are stabilized by CLFs. We demonstrate the advantages of using aCBFs over the existing CBF techniques by applying both the PACBF-based method and the RACBF-based method to a cruise control problem with time-varying road conditions and noise in the system dynamics, and compare their relative performance.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Local Mean Payoff Supervisory Control for Discrete Event Systems

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      Authors: Yiding Ji;Xiang Yin;Stéphane Lafortune;
      Pages: 2282 - 2297
      Abstract: This article investigates quantitative supervisory control with local mean payoff objectives on discrete event systems modeled as weighted automata. Weight flows are generated as new events occur, which are required to satisfy some quantitative conditions. We focus on mean weights (payoffs) over a finite number of events, which serve as a measure for the stability or robustness of weight flows. The range of events to evaluate the mean payoff is termed a window, which slides as new events occur. Qualitative requirements such as safety and liveness are also necessary along with quantitative requirements. Supervisory control is employed to manipulate the operation of the system so that the requirements are satisfied. We consider two different scenarios based on whether the window size is fixed or not. Correspondingly, we formulate two supervisory control problems, both of which are solved sequentially by first tackling the qualitative issues and then the quantitative ones. The automaton model is then transformed to a two-player game between the supervisor and the environment, where safety and liveness are enforced. Based on the intermediate results, several quantitative objectives are defined to formulate two games, which correspond to the two proposed supervisory control problems. Finally, we synthesize provably correct supervisors by solving the games and completely resolve both problems.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Stable Near-Optimal Control of Nonlinear Switched Discrete-Time Systems:
           An Optimistic Planning-Based Approach

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      Authors: Mathieu Granzotto;Romain Postoyan;Lucian Buşoniu;Dragan Nešić;Jamal Daafouz;
      Pages: 2298 - 2313
      Abstract: Originating in the artificial intelligence literature, optimistic planning (OP) is an algorithm that generates near-optimal control inputs for generic nonlinear discrete-time systems whose input set is finite. This technique is, therefore, relevant for the near-optimal control of nonlinear switched systems for which the switching signal is the control, and no continuous input is present. However, OP exhibits several limitations, which prevent its desired application in a standard control engineering context, as it requires, for instance, that the stage cost takes values in $[0, 1]$, an unnatural prerequisite, and that the cost function is discounted. In this article, we modify OP to overcome these limitations, and we call the new algorithm ${rm OP}_{text{min}}$. We then analyze ${rm OP}_{text{min}}$ under general stabilizability and detectability assumptions on the system and the stage cost. New near-optimality and performance guarantees for ${rm OP}_{text{min}}$ are derived, which have major advantages compared to those originally given for OP. We also prove that a system whose inputs are generated by ${rm OP}_{text{min}}$ in a receding-horizon fashion exhibits stability properties. As a result, ${rm OP}_{text{min}}$ provides a new tool for the near-optimal, stable control of nonlinear switched discrete-time systems for generic cost functions.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Online Supervisory Control of Networked Discrete Event Systems With
           Control Delays

    • Free pre-print version: Loading...

      Authors: Zhaocong Liu;Xiang Yin;Shaolong Shu;Feng Lin;Shaoyuan Li;
      Pages: 2314 - 2329
      Abstract: We investigate state estimation and safe controller synthesis for networked discrete-event systems (DESs), where supervisors send control decisions to plants via communication channels subject to communication delays. Previous works on state estimation of networked DES are based on the open-loop system without utilizing the knowledge of the control policy. In this article, we propose a new approach for online estimation and control of networked DES with control delays. We first propose a new state estimation algorithm for the closed-loop system utilizing the information of control decision history. The proposed state estimation algorithm can be implemented recursively upon the occurrence of each new observable event. Then we investigate how to predict the effect of control delays in order to calculate a control decision online at each instant. We show that the proposed online supervisor can be updated effectively and the resulting closed-loop behavior is safe. Furthermore, we compare the proposed online supervisor with the predictive supervisor proposed in the literature and show that our proposed online supervisor is more permissive than predictive supervisor in the sense of language inclusion.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Sample Complexity and Minimax Properties of Exponentially Stable
           Regularized Estimators

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      Authors: Gianluigi Pillonetto;Anna Scampicchio;
      Pages: 2330 - 2342
      Abstract: Recent studies have shown how regularization may play an important role in linear system identification. An effective approach consists of searching for the impulse response in a high-dimensional space, e.g., a reproducing kernel Hilbert space (RKHS). Complexity is then controlled using a regularizer, e.g., the RKHS norm, able to encode smoothness and stability information. Examples are RKHSs induced by the so-called stable spline or tuned-correlated kernels, which contain a parameter that regulates impulse response exponential decay. In this article, we derive nonasymptotic upper bounds on the $ell _2$ error of these regularized schemes and study their optimality in order (in the minimax sense). Under white noise inputs and Gaussian measurement noises, we obtain conditions which ensure the optimal convergence rate for all the class of stable spline estimators and several generalizations. Theoretical findings are then illustrated via a numerical experiment.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Regularized Diffusion Adaptation via Conjugate Smoothing

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      Authors: Stefan Vlaski;Lieven Vandenberghe;Ali H. Sayed;
      Pages: 2343 - 2358
      Abstract: The purpose of this article is to develop and study a decentralized strategy for Pareto optimization of an aggregate cost consisting of regularized risks. Each risk is modeled as the expectation of some loss function with unknown probability distribution, while the regularizers are assumed deterministic, but are not required to be differentiable or even continuous. The individual, regularized, cost functions are distributed across a strongly connected network of agents, and the Pareto optimal solution is sought by appealing to a multiagent diffusion strategy. To this end, the regularizers are smoothed by means of infimal convolution, and it is shown that the Pareto solution of the approximate smooth problem can be made arbitrarily close to the solution of the original nonsmooth problem. Performance bounds are established under conditions that are weaker than assumed before in the literature and, hence, applicable to a broader class of adaptation and learning problems.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • When Selfish is Socially Optimal

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      Authors: Petros G. Voulgaris;Nicola Elia;
      Pages: 2359 - 2372
      Abstract: In this article, we consider cooperative multiagent systems, where independent agents need to minimize a collective social cost. Given the coupling in the cost, the optimal strategy requires interaction and communications among all the agents in general. In this article, we unveil important classes of social costs which are optimized by decentralized and selfish solutions, hence eliminating the need for an interagent communication network. In particular, we focus on a set of $n$ independent agents coupled only through an overall cost that penalizes the divergence of each agent from the average collective behavior. Adopting input–output methods, we show that optimal decentralized and selfish solutions are possible in a variety of standard input–output cost criteria. These include the cases of $ell _1$, $ell _2$, $ell _infty$ induced, and ${mathcal H}_2$ norms for any finite $n$. Moreover, if the cost includes nondeviation from average variables, the above results hold true as well for $ell _1$, $ell _2$, $ell _infty$ induced norms, and any $n$, while they hold true for the normalized, per-agent square ${mathcal H}_2$ norm, cost as $nrightarrow infty$. The results of the article demonstrate that selfish behavior can be socially optimal in nontrivial cases. We further expand our analysis to more general controller structures that induce collective tracking of exogenous common signals.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Non-asymptotic Confidence Regions for the Transfer Functions of
           Errors-in-Variables Systems

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      Authors: Masoud Moravej Khorasani;Erik Weyer;
      Pages: 2373 - 2388
      Abstract: Finite-sample system identification (FSID) methods provide guaranteed confidence regions for the unknown model parameter of dynamical systems under mild statistical assumptions for a finite number of data points. In this article, two FSID methods, the leave-out sign-dominant correlation region (LSCR) and sign-perturbed sums (SPS) methods are extended to errors-in-variables (EIV) systems. In EIV systems, both the measured input and the measured output are corrupted by noise, and they are not noise invertible in the sense that the noise signals cannot be recovered from the measured signals given the true system. Hence, standard FSID methods are not applicable. The present article deals with FSID of EIV systems where the input and noise on input are i.i.d. Gaussian processes and the signal-to-noise ratio is known. By utilizing an alternative regression model and swapping the role of the input and the prediction error in the FSID methods, new LSCR and SPS confidence regions are constructed, which include the true model parameter with a guaranteed user-chosen probability. It is shown that the confidence regions are asymptotically included in an $epsilon$-neighborhood of the true parameter. An ellipsoidal approximation which can be computed at low computational cost is proposed for the SPS confidence region. The methods and their properties are illustrated in numerical experiments.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Folding Bilateral Backstepping Output-Feedback Control Design for an
           Unstable Parabolic PDE

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      Authors: Stephen Chen;Rafael Vazquez;Miroslav Krstic;
      Pages: 2389 - 2404
      Abstract: We present a novel methodology for designing output-feedback backstepping bilateral boundary controllers for an unstable 1D diffusion-reaction partial differential equation (PDE) with spatially varying reaction. Using folding transforms the parabolic PDE into a $2 times 2$ coupled PDE system with coupling through compatibility conditions. We apply a two-tiered backstepping approach, where the invertibility of the transformations guarantees the state-feedback controllers exponentially stabilize the trivial solution of the PDE system. A state observer is also designed for two collocated measurements at an arbitrary interior point, generating exponentially stable state estimates. The output feedback control law is formulated by composing the independently designed state-feedback controller with the observer, and the resulting dynamic feedback is shown to stabilize the trivial solution. Some numerical analysis on how the selection of these points affect the responses of the controller and observer are discussed, with simulations illustrating various choices of folding points and their effect on the stabilization in different performance indexes.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Dual Set Membership Filter With Minimizing Nonlinear Transformation of
           Ellipsoid

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      Authors: Zhiguo Wang;Xiaojing Shen;Haiqi Liu;Fanqin Meng;Yunmin Zhu;
      Pages: 2405 - 2418
      Abstract: In this article, we propose a dual set membership filter for nonlinear dynamic systems with additive unknown but bounded noises, and it has three distinct advantages. First, the nonlinear system is translated into the linear system by leveraging a semi-infinite programming, rather than linearizing the nonlinear function. The semi-infinite programming is to find an ellipsoid bounding the nonlinear transformation of an ellipsoid, which aims to compute a tight ellipsoid to cover the state. Second, the duality result of the semi-infinite programming is derived by rigorous analysis; then, a first-order Frank–Wolfe method is developed to efficiently solve it with a lower computation complexity. Third, the proposed filter enjoys stability for some special nonlinear dynamic systems and succeeds the advantages of the classic linear set membership filter. Finally, two illustrative examples in the simulations reveal the effectiveness of the dual set membership filter.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Constrained Nonlinear Output Regulation Using Model Predictive Control

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      Authors: Johannes Köhler;Matthias A. Müller;Frank Allgöwer;
      Pages: 2419 - 2434
      Abstract: We present a model predictive control (MPC) framework to solve the constrained nonlinear output regulation problem. The main feature of the proposed framework is that the application does not require the solution to classical regulator (Francis–Byrnes–Isidori) equations or any other offline design procedure. In particular, the proposed formulation simply minimizes the predicted output error, possibly with some input regularization. Instead of using terminal cost/sets or a positive-definite stage cost as is standard in MPC theory, we build on the theoretical results by Grimm et al. using a detectability notion. The proposed formulation is applicable if the constrained nonlinear regulation problem is (strictly) feasible; the plant is incrementally stabilizable and incrementally input–output to state stable (i-IOSS, detectable). We show that for minimum phase systems, such a design ensures exponential stability of the regulator manifold. We also provide a design procedure in case of unstable zero dynamics using an incremental input regularization and a nonresonance condition. The theoretical results are illustrated with an example involving offset-free tracking.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Convergence and Sample Complexity of Gradient Methods for the Model-Free
           Linear–Quadratic Regulator Problem

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      Authors: Hesameddin Mohammadi;Armin Zare;Mahdi Soltanolkotabi;Mihailo R. Jovanović;
      Pages: 2435 - 2450
      Abstract: Model-free reinforcement learning attempts to find an optimal control action for an unknown dynamical system by directly searching over the parameter space of controllers. The convergence behavior and statistical properties of these approaches are often poorly understood because of the nonconvex nature of the underlying optimization problems and the lack of exact gradient computation. In this article, we take a step toward demystifying the performance and efficiency of such methods by focusing on the standard infinite-horizon linear–quadratic regulator problem for continuous-time systems with unknown state-space parameters. We establish exponential stability for the ordinary differential equation (ODE) that governs the gradient-flow dynamics over the set of stabilizing feedback gains and show that a similar result holds for the gradient descent method that arises from the forward Euler discretization of the corresponding ODE. We also provide theoretical bounds on the convergence rate and sample complexity of the random search method with two-point gradient estimates. We prove that the required simulation time for achieving $epsilon$-accuracy in the model-free setup and the total number of function evaluations both scale as $log , (1/epsilon)$.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Differentially Private Distributed Nash Equilibrium Seeking for
           Aggregative Games

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      Authors: Maojiao Ye;Guoqiang Hu;Lihua Xie;Shengyuan Xu;
      Pages: 2451 - 2458
      Abstract: This article considers the privacy-preserving distributed Nash equilibrium seeking strategy design for average aggregative games, in which the players’ objective functions are considered to be sensitive information to be protected. In particular, we consider that the game is free of central node and the aggregate information is not directly available to the players. As there is no central authority to provide the aggregate information required by each player to update their actions, a dynamic average consensus protocol is employed to estimate it. To protect the players’ privacy, we perturb the transmitted information among the players by independent random noises drawn from Laplace distributions. By synthesizing the perturbed average consensus protocol with a gradient algorithm, a distributed privacy-preserving Nash equilibrium seeking strategy is established for the aggregative games under both fixed and time-varying communication topologies. With explicit quantifications of the mean square errors, the convergence results of the proposed methods are presented. Moreover, it is analytically proven that the proposed algorithm is $epsilon$-differentially private. The presented results indicate that there is a tradeoff between the convergence accuracy and the privacy level. Last, a numerical example is provided for the verification of the proposed methods.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • A Distributed Active Perception Strategy for Source Seeking and Level
           Curve Tracking

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      Authors: Said Al-Abri;Fumin Zhang;
      Pages: 2459 - 2465
      Abstract: Algorithms for multiagent systems to locate a source or to follow a desired level curve of spatially distributed scalar fields generally require sharing field measurements among the agents for gradient estimation. Yet, in this article, we propose a distributed active perception strategy that enables swarms of various sizes and graph structures to perform source seeking and level curve tracking without the need to explicitly estimate the field gradient or explicitly share measurements. The proposed method utilizes a consensus-like principal component analysis perception algorithm that does not require explicit communication in order to compute a local body frame. This body frame is used to design a distributed control law where each agent modulates its motion based only on its instantaneous field measurement. Several stability results are obtained within a singular perturbation framework that justifies the convergence and robustness of the strategy. Additionally, efficiency is validated through robots experiments.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Sampled-Data Model Predictive Control

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      Authors: José C. Geromel;
      Pages: 2466 - 2472
      Abstract: This article focuses on model predictive control (MPC) design in the context of sampled-data control systems with full-state measurements. It is shown that recent results on this area can be successfully generalized to cope with sampled-data MPC. The open-loop plant is subjected to polytopic parameter uncertainty and at sampling times, a controlled output variable satisfies a set of convex constraints. A guaranteed ${mathcal H}_2$ performance index with infinity horizon is minimized such that the feedback control preserves asymptotic stability and feasibility. The design conditions are expressed through differential linear matrix inequalities. Continuous-time systems are treated with no kind of discrete-time modeling approximation. Comparisons with classical methods from the literature dealing with continuous-time systems are presented and discussed. Examples are included for illustration.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Mean Square Exponential Stability Analysis for Itô Stochastic Systems
           With Aperiodic Sampling and Multiple Time-Delays

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      Authors: Guoliang Chen;Chenchen Fan;Jian Sun;Jianwei Xia;
      Pages: 2473 - 2480
      Abstract: In this article, for Itô stochastic systems with aperiodic sampling and multiple time-delays, we provide two different types of mean square exponential stability analysis methods. One method is based on the Razumikhin-type theorems method, based on this method, the mean square exponential stability criteria of the system are proposed. Meanwhile, mean square exponential practical stability criteria are also proposed. In addition, through these theorems, the constraint of positivity on the Lyapunov function for all times can be relaxed to sampling times for Itô stochastic systems with aperiodic sampling and multiple time-delays is proved. Another method is based on the looped-functionals method. Two looped-functionals are introduced to analyze the stability of Itô stochastic systems with aperiodic sampling and multiple time-delays. One functional is one-sided, while the other functional is two-sided. Based on these two functionals and the Itô formula, two mean square exponential stability criteria are presented in the form of linear matrix inequalities. Numerical examples are used to illustrate that the proposed approach is less conservative than other methods.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Adaptive Formation Tracking Control for First-Order Agents With a
           Time-Varying Flow Parameter

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      Authors: Yang-Yang Chen;Kaiwen Chen;Alessandro Astolfi;
      Pages: 2481 - 2488
      Abstract: A novel adaptive method to achieve both path following and formation moving along desired orbits in the presence of a spatio-temporal flowfield is presented. The flowfield is a spatio-temporal general flow with unknown time-varying parameters. The so-called congelation of variables method is used to estimate the time-varying flow parameters, which do not have any restrictions on the rate of their variation. The asymptotic properties of the resulting adaptive system are studied in detail. Simulation results demonstrate the effectiveness of the proposed method.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Distributed Error Estimation for Quasi-Synchronization of Heterogeneous
           Dynamical Networks

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      Authors: Bohui Wang;
      Pages: 2489 - 2496
      Abstract: This article proposes a distributed error estimation approach to investigate the quasi-synchronization problem of heterogeneous dynamical networks with static and adaptive coupling laws under a directed communication topology. By introducing a pining control strategy, a novel class of distributed error estimation algorithms is proposed for solving the quasi-synchronization problem of heterogeneous dynamical networks with a static coupling law by exploring the local information among the neighboring nodes. By removing the assumption that the smallest real part of the nonzero eigenvalues of the Laplacian matrix associated with the communication graph must be known, we also address the case of the quasi-synchronization of heterogeneous dynamical networks with nonidentical nonlinear dynamics and an adaptive coupling law. It is proved, in the sense of Lyapunov function, that the distributed error estimation for the quasi-synchronization problem of heterogeneous dynamical networks with static and adaptive coupling laws will be achieved with a bounded synchronization error level. Finally, two examples are presented to demonstrate the effectiveness of the proposed approaches.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Functional Interval Observer for Discrete-Time Switched Descriptor Systems

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      Authors: Jun Huang;Haochi Che;Tarek Raïssi;Zhenhua Wang;
      Pages: 2497 - 2504
      Abstract: This article investigates functional interval observer based estimation methods for discrete-time switched descriptor systems with disturbances. A functional observer is presented using the $H_infty$ formalism, and then a zonotope-based approach is applied to estimate its boundaries with a reduction of observer design constraints. To avoid the wrapping effect brought by the order reduction operations in the zonotope approach, reachability analysis is combined with the $H_infty$ technique to design a switched functional interval observer with a better performance. Moreover, the relationship between the existing method, zonotope approach, and reachability analysis method is discussed in detail. The aforementioned methods are applied to an example for comparisons and to show their performance.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Stability Analysis of Nash Equilibrium for Two-Agent Loss-Aversion-Based
           Noncooperative Switched Systems

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      Authors: Yuyue Yan;Tomohisa Hayakawa;
      Pages: 2505 - 2513
      Abstract: The stability property of the loss-aversion-based noncooperative switched systems with quadratic payoffs is investigated. In this system, each agent adopts the lower sensitivity parameter in the myopic pseudo-gradient dynamics for the case of losing utility than gaining utility, and both system dynamics and switching events (conditions) are depending on agents’ payoff functions. Sufficient conditions under which agents’ state converges toward the Nash equilibrium are derived in accordance with the location of the Nash equilibrium. In the analysis, the mode transition sequence and interesting phenomena, which we call flash switching are characterized. We present several numerical examples to illustrate the properties of our results.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Scalable Vehicle Team Continuum Deformation Coordination With Eigen
           Decomposition

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      Authors: Hossein Rastgoftar;Ella M. Atkins;Ilya V. Kolmanovsky;
      Pages: 2514 - 2521
      Abstract: The continuum deformation leader–follower cooperative control strategy models vehicles in a multiagent system as particles of a deformable body. A desired continuum deformation is defined based on leaders’ trajectories and acquired by followers in real time through local communication. The existing continuum deformation theory requires followers to be placed inside the convex simplex defined by leaders. This constraint is relaxed in this article. We prove that, under suitable assumptions, any $n+1$ ($n=1,2,3$) vehicles forming an $n$-D simplex can be selected as leaders while followers, arbitrarily positioned inside or outside the leading simplex, can acquire a desired continuum deformation in a decentralized fashion. The article’s second contribution is to assign a one-to-one mapping between leaders’ smooth trajectories and homogeneous deformation features obtained by continuum deformation eigendecomposition. Therefore, a safe and smooth continuum deformation coordination can be planned either by shaping homogeneous transformation features or by choosing appropriate leader trajectories. This is beneficial to efficiently plan and guarantee collision avoidance in a large-scale group. A simulation case study is reported in which a virtual convex simplex contains a quadcopter vehicle team at any time $t$; A* search is applied to optimize quadcopter team continuum deformation in an obstacle-laden environment.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Minimal Controllability Problems on Linear Structural Descriptor Systems

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      Authors: Shun Terasaki;Kazuhiro Sato;
      Pages: 2522 - 2528
      Abstract: We consider minimal controllability problems (MCPs) on linear structural descriptor systems. We address two problems of determining the minimum number of input nodes such that a descriptor system is structurally controllable. We show that MCP0 for structural descriptor systems can be solved in polynomial time. This is the same as the existing results on typical structural linear time-invariant (LTI) systems. However, the derivation of the result is considerably different because the derivation technique of the existing result cannot be used for descriptor systems. Instead, we use the Dulmage–Mendelsohn decomposition. Moreover, we prove that the results for MCP1 are different from those for usual LTI systems. In fact, MCP1 for descriptor systems is an NP-hard problem, while MCP1 for LTI systems can be solved in polynomial time.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Decentralized Observer Design for Virtual Decomposition Control

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      Authors: Jukka-Pekka Humaloja;Janne Koivumäki;Lassi Paunonen;Jouni Mattila;
      Pages: 2529 - 2536
      Abstract: In this article, we incorporate velocity observer design into the virtual decomposition control (VDC) strategy of an $n$-degree of freedom ($n$-DoF) open-chain robotic manipulator. Descending from the VDC strategy, the proposed design is based on decomposing the $n$-DoF manipulator into subsystems, i.e., rigid links and joints, for which the decentralized controller–observer implementation can be done locally. Similar to VDC, the combined controller–observer design is passivity based, and we show that it achieves semiglobal exponential convergence of the tracking error. The convergence analysis is carried out using Lyapunov functions based on the observer and controller error dynamics. The proposed design is demonstrated in a simulation study of a 2-DoF open-chain robotic manipulator in the vertical plane.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Parameterization of All Output-Rectifying Retrofit Controllers

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      Authors: Hampei Sasahara;Takayuki Ishizaki;Jun-ichi Imura;
      Pages: 2537 - 2543
      Abstract: This article investigates a parameterization of all output-rectifying retrofit controllers for distributed design of a structured controller. It has been discovered that all retrofit controllers can be characterized as a constrained Youla parameterization, which is difficult to solve analytically. For synthesis, a tractable and insightful class of retrofit controllers, referred to as output-rectifying retrofit controllers, has been introduced. An unconstrained parameterization of all output-rectifying retrofit controllers can be derived under a technical assumption on measurability of the interaction signal. The aim of this article is to reveal the structure of all output-rectifying retrofit controllers in the general output-feedback case without interaction measurement. It is found out that the existing developments can be generalized based on system inversion. The result leads to the conclusion that output-rectifying retrofit controllers can readily be designed even in the general case.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Rethinking the Mathematical Framework and Optimality of Set-Membership
           Filtering

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      Authors: Yirui Cong;Xiangke Wang;Xiangyun Zhou;
      Pages: 2544 - 2551
      Abstract: Set-membership filter (SMF) has been extensively studied for state estimation in the presence of bounded noises with unknown statistics. Since it was first introduced in the 1960s, the studies on SMF have used the set-based description as its mathematical framework. One important issue that has been overlooked is the optimality of SMF. In this article, we put forward a new mathematical framework for SMF using concepts of uncertain variables. We first establish two basic properties of uncertain variables, namely, the law of total range (a nonstochastic version of the law of total probability) and the equivalent Bayes’ rule. This enables us to put forward a general SMFing framework with established optimality. Furthermore, we obtain the optimal SMF under a nonstochastic Markov condition, which is shown to be fundamentally equivalent to the Bayes filter. Note that the classical SMF in the literature is only equivalent to the optimal SMF we obtained under the nonstochastic Markov condition. When this condition is violated, we show that the classical SMF is not optimal and it only gives an outer bound on the optimal estimate.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Continuous-Time Algorithm Based on Finite-Time Consensus for Distributed
           Constrained Convex Optimization

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      Authors: Hongzhe Liu;Wei Xing Zheng;Wenwu Yu;
      Pages: 2552 - 2559
      Abstract: This article studies the convex optimization problem with general constraints, where its global objective function is composed of the sum of local objective functions. The objective is to design a distributed algorithm to cooperatively resolve the optimization problem under the condition that only the information of each node’s own local cost function and its neighbors’ states can be obtained. To this end, the optimality condition of the researched optimization problem is developed in terms of the saddle point theory. On this basis, the corresponding continuous-time primal-dual algorithm is constructed for the considered constrained convex optimization problem under time-varying undirected and connected graphs. In the case that the parameters involved in the proposed algorithm satisfy certain inequality, the states of all nodes will reach consensus in finite time. Meanwhile, the average state is globally convergent to the optimal solution of the considered optimization problem under some mild and standard assumptions.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Fault-Tolerant Consensus Control for Multiagent Systems: An
           Encryption-Decryption Scheme

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      Authors: Chen Gao;Zidong Wang;Xiao He;Hongli Dong;
      Pages: 2560 - 2567
      Abstract: In this article, the fault-tolerant consensus control problem is investigated for multiagent systems with sensor faults. A first-order difference equation is utilized to describe the sensor fault, and an observer is designed to estimate the state and the fault simultaneously. For security enhancement and/or congestion mitigation purposes, the estimated state is first encrypted into a series of finite-level codewords by an encryption algorithm and, then, transmitted to other agents through a directed topology. After being received, the codewords are then decrypted by the corresponding decryption algorithm and subsequently utilized to design the consensus controller. By constructing a novel matrix norm along with its compatible vector norm, we obtain a necessary and sufficient condition, which serves as an index in the observer and the controller design. In the end, a simulation example is given to demonstrate the validity of the results in this article.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Leader-Following Consensus of Multiagent Systems via Asynchronous
           Sampled-Data Control: A Hybrid System Approach

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      Authors: Guanglei Zhao;Changchun Hua;
      Pages: 2568 - 2575
      Abstract: In this article, we develop a hybrid system approach for sampled-data-based leader-following consensus of multiagent systems over a static/switching directed network. First, an asynchronous sampled-data hybrid consensus control protocol is proposed, which has an extra reset control part in contrast with the traditional linear control protocol and is beneficial for achieving better transient consensus performance. Then, with several properly defined internal variables, a hybrid model consisting of both flow and jump dynamics is constructed to describe the closed-loop dynamics. Based on this model and internal decreasing functions, Lyapunov-based stability conditions are derived, and larger upper bound of sampling period can be obtained compared to the existing related work. Finally, an example is given to show the superiority of the proposed approach.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • On the Existence and Computation of Minimum Attention Optimal Control Laws

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      Authors: Pilhwa Lee;Frank Park;
      Pages: 2576 - 2581
      Abstract: One means of capturing the cost of control implementation of a general nonlinear control system is via Brockett’s minimum attention criterion, defined as a multidimensional integral of the rate of change of the control with respect to state and time. Although shown to be important in human motor control and robotics applications, a practical difficulty with this criterion is that the existence of solutions is not always assured; even when they exist, obtaining local solutions numerically is difficult. In this article, we prove that, for the class of controls consisting of the sum of a time-varying feedforward term and a time-varying feedback term linear in the state, existence of a suboptimal solution can be guaranteed. We also derive a provably convergent gradient descent algorithm for obtaining a local solution, by appealing to the Liouville equation representation of a nonlinear control system and adapting iterative methods originally developed for boundary flow control. Our methodology is illustrated with a two degree-of-freedom planar robot example.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • A Distributed Optimization Scheme for State Estimation of Nonlinear
           Networks With Norm-Bounded Uncertainties

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      Authors: Peihu Duan;Qishao Wang;Zhisheng Duan;Guanrong Chen;
      Pages: 2582 - 2589
      Abstract: This article investigates state estimation for a class of complex networks, in which the dynamics of each node is subject to Gaussian noise, system uncertainties, and nonlinearities. Based on a regularized least-squares approach, the estimation problem is reformulated as an optimization problem, solving for a solution in a distributed way by utilizing a decoupling technique. Then, based on this solution, a class of estimators is designed to handle the system dynamics and constraints. A novel feature of this design lies in the unified modeling of uncertainties and nonlinearities, the decoupling of nodes, and the construction of recursive approximate covariance matrices for the optimization problem. Furthermore, the feasibility of the proposed estimators and the boundedness of mean-square estimation errors are ensured under a developed criterion, which is easier to check than some typical estimation strategies including the linear matrix inequalities-based and the variance-constrained ones. Finally, the effectiveness of the theoretical results is verified by a numerical simulation.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • New Design on Distributed Event-Based Sliding Mode Controller for
           Disturbed Second-Order Multiagent Systems

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      Authors: Xihui Wu;Xiaowu Mu;
      Pages: 2590 - 2596
      Abstract: This article restudies the tracking consensus problem of disturbed second-order multiagent systems via event-based sliding mode control (EB-SMC). A new framework of EB-SMC method is proposed with new distributed EB integral-type sliding manifolds, distributed EB-SMCs, and more efficient event-triggered detections where continuous communication among follower agents is not required. Moreover, event-triggered conditions with heterogeneous parameters are well-designed to improve the flexibility of parameters selection. By employing Lyapunov analysis method and SMC theory, new sufficient conditions for ensuring the reachability of sliding manifold is deduced to remove the conservatism. In light of EB-SMC technique, attractive features containing fast response, good transient performance, and robustness with respect to uncertainties can be inherited. Also, resource consumption and network occupation can be greatly reduced via event-triggered control with exclusion of Zeno phenomena. At last, a numerical example is shown to support our results.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Edge-Based Adaptive Distributed Method for Synchronization of
           Intermittently Coupled Spatiotemporal Networks

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      Authors: Cheng Hu;Haibo He;Haijun Jiang;
      Pages: 2597 - 2604
      Abstract: In biology networks, social networks, mobile robots, and many real networks, spatial factors are crucial to the evolution of networks and individual interactions are not always continuous. In this article, a kind of intermittently coupled spatiotemporal networks (ICSNs) is proposed, where the couplings among nodes are intermittent and the coupling strengths are related to both time and space. By constructing piecewise auxiliary functions and developing a direct error method, a distributed intermittent adaptive protocol and its pinning form are designed to determine the space-time dependent weights of edges to realize synchronization of ICSNs. Lastly, the theoretical analysis is supported by means of a numerical example.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • On the Lyapunov Foster Criterion and Poincaré Inequality for
           Reversible Markov Chains

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      Authors: Amirhossein Taghvaei;Prashant G. Mehta;
      Pages: 2605 - 2609
      Abstract: This article presents an elementary proof of stochastic stability of a discrete-time reversible Markov chain starting from a Foster–Lyapunov drift condition. Besides its relative simplicity, there are two salient features of the proof. 1) It relies entirely on functional-analytic non-probabilistic arguments. 2) It makes explicit the connection between a Foster–Lyapunov function and Poincaré inequality. The proof is used to derive an explicit bound for the spectral gap. An extension to the nonreversible case is also presented.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • A New Approach to Finite-Horizon Optimal Control for Discrete-Time Affine
           Nonlinear Systems via a Pseudolinear Method

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      Authors: Qinglai Wei;Liao Zhu;Tao Li;Derong Liu;
      Pages: 2610 - 2617
      Abstract: In this article, a new time-varying adaptivedynamic programming (ADP) algorithm is developed to solve finite-horizon optimal control problems for a class of discrete-time affine nonlinear systems. Inspired by the pseudolinear method, the nonlinear system can be approximated by a series of time-varying linear systems. In each iteration of the time-varying ADP algorithm, the optimal control law for the time-varying linear system is obtained. For an arbitrary initial state, it is proven that states of the time-varying linear systems converge to the states of discrete-time affine nonlinear systems. It is also shown that the iterative value functions and the iterative control laws converge to the optimal value function and the optimal control law, respectively. Finally, numerical results are presented to verify the effectiveness of the present method.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • An Analysis of Closed-Loop Stability for Linear Model Predictive Control
           Based on Time-Distributed Optimization

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      Authors: Dominic Liao-McPherson;Terrence Skibik;Jordan Leung;Ilya Kolmanovsky;Marco M. Nicotra;
      Pages: 2618 - 2625
      Abstract: Time-distributed optimization (TDO) is an approach for reducing the computational burden of model predictive control (MPC) and a generalization of the real-time iteration scheme. When using TDO, optimization iterations are distributed over time by maintaining a running solution estimate and updating it at each sampling instant. In this article, TDO applied to input-constrained linear-quadratic MPC is studied in detail, and an analytic bound for the number of optimization iterations per sampling instant required to guarantee closed-loop stability is derived. Further, it is shown that the closed-loop stability of TDO-based MPC can be guaranteed using multiple mechanisms, including increasing the number of solver iterations, preconditioning the optimal control problem, adjusting the MPC cost matrices, and reducing the length of the receding horizon. These results in a linear system setting also provide insights and guidelines that could be more broadly applicable, for example, to nonlinear MPC.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • A Robust and Resilient State Estimation for Linear Systems

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      Authors: Yechan Jeong;Yongsoon Eun;
      Pages: 2626 - 2632
      Abstract: This article is concerned with the state estimation of linear dynamic systems when some sensors are corrupted by attackers. This problem is known as resilient state estimation (RSE), and aims to achieve, under some conditions, the estimation of the true state despite the malicious attacks on sensors. The state-of-art RSE methods provides a bound on estimation errors when external disturbance exists. However, it is shown in this article that the effect of the disturbance on estimation error may be larger than that for conventional observers, or even worse, resiliency may be lost for the disturbance that exceeds the bound. To resolve this issue, unknown input observer (UIO) mechanism is adopted in RSE for the purpose of estimating true plant state under both sensor attacks and external disturbance. Also achieved in this work is the method of partial state UIO synthesis, which relaxes the design requirement for full state UIO. In relation to resiliency, it is shown that 2$q$ redundant detectability is a necessary condition for robust and resilient state estimator in order to tolerate up to $q$ sensor attacks. Numerical examples are given to validate the effectiveness of the proposed method.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Social Media and Misleading Information in a Democracy: A Mechanism Design
           Approach

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      Authors: Aditya Dave;Ioannis Vasileios Chremos;Andreas A. Malikopoulos;
      Pages: 2633 - 2639
      Abstract: In this article, we present a resource allocation mechanism to incentivize misinformation filtering among strategic social media platforms and, thus, to indirectly prevent the spread of fake news. We consider the presence of a strategic government and private knowledge of how misinformation affects the users of the social media platforms. Our proposed mechanism strongly implements all generalized Nash equilibria for efficient filtering of misleading information in the induced game, with a balanced budget. We also show that for quasi-concave utilities, our mechanism implements a Pareto efficient solution.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Low-Complexity Tracking Control for p-Normal Form Systems Using a Novel
           Nussbaum Function

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      Authors: Chao Ding;Ruixuan Wei;
      Pages: 2640 - 2647
      Abstract: This article proposes a low-complexity control design for a class of nonlinear systems in p-normal form whose control directions are completely unknown. The novel contributions, as opposed to the state-of-the-art, of this study lie in the following twofold: to relax the conditional inequality regarding the derivative of Lyapunov function, a novel Nussbaum function with changing frequency is constructed, based on which an improved Nussbaum gain technical lemma is first designed such that closed-loop boundedness can be established for all time, rather than the forward completeness property (boundedness up to any finite time); to further handle nonaffine terms, the concept named separable characteristic is put forward, making the controlled systems more compatible with several general frameworks derived from backstepping-like technique. Thanks to abovementioned benefits, a prescribed performance control methodology is presented without involving any approximation techniques. Theoretical results are demonstrated via numerical simulation.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Controller Design for Plants With Internal Delayed Feedback

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      Authors: A. N. Gündeş;Hitay Özbay;
      Pages: 2648 - 2654
      Abstract: A special class of retarded and neutral time delay systems is considered. These are plants with internal delayed feedback, and they may have finitely many or infinitely many unstable poles. Stabilizing controllers are obtained from a particular interpolation. A parametrization of all stabilizing integral-action controllers is obtained. Examples are given to illustrate this simple design procedure and its robustness properties for various uncertainties.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • $L_{1}$ -Gain+Analysis+of+Periodic+Piecewise+Positive+Systems+With+Constant+Time+Delay&rft.title=IEEE+Transactions+on+Automatic+Control&rft.issn=0018-9286&rft.date=2022&rft.volume=67&rft.spage=2655&rft.epage=2662&rft.aulast=Kwok;&rft.aufirst=Bohao&rft.au=Bohao+Zhu;James+Lam;Xiaochen+Xie;Xiaoqi+Song;Ka-Wai+Kwok;">Stability and $L_{1}$ -Gain Analysis of Periodic Piecewise Positive
           Systems With Constant Time Delay

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      Authors: Bohao Zhu;James Lam;Xiaochen Xie;Xiaoqi Song;Ka-Wai Kwok;
      Pages: 2655 - 2662
      Abstract: This article is concerned with the stability and $L_{1}$-gain analysis of periodic piecewise positive systems with constant time delay. $lambda$-exponential stability, which is applied to characterize the decay rates of the considered systems, is investigated first. A copositive Lyapunov–Krasovskii functional is used to obtain a sufficient stability condition. The stability condition characterizes the convergent speed of the state by the system matrices and the size of the time delay. One can also apply the Lyapunov–Krasovskii functional to characterize the $L_{1}$-gain of the systems. By taking advantage of the periodic property of the system, linear inequalities are employed to characterize the $L_{1}$-gain, and an unweighted upper bound of the $L_{1}$-gain of the system is given.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Modular Adaptive Backstepping Design With a High-Order Tuner

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      Authors: Vladimir Nikiforov;Dmitry Gerasimov;Artem Pashenko;
      Pages: 2663 - 2668
      Abstract: This article addresses the problem of transient performance improvement in adaptive backstepping design. A new modular design with a high-order tuner providing complete compensation of the adjustable parameters’ time variations is proposed. The ${mathcal L}_infty$ performance bound for the state error is derived and verifies a better transient performance of the proposed controller compared to the known ones designed based on tuning functions and modular approach with first-order tuners.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Distributed Observer-Based Cooperative Control Approach for Uncertain
           Nonlinear MASs Under Event-Triggered Communication

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      Authors: Chao Deng;Changyun Wen;Jiangshuai Huang;Xian-Ming Zhang;Ying Zou;
      Pages: 2669 - 2676
      Abstract: The distributed tracking problem for uncertain nonlinear multiagent systems (MASs) under event-triggered communication is an important issue. However, existing results provide solutions that can only ensure stability with bounded tracking errors, as asymptotic tracking is difficult to be achieved mainly due to the errors caused by event-triggering mechanisms and system uncertainties. In this article, with the aim of overcoming such difficulty, we propose a new methodology. The subsystems in MASs are divided into two groups, in which the first group consists of the subsystems that can access partial output of the reference system and the second one contains all the remaining subsystems. To estimate the state of the reference system, a new distributed event-triggered observer is first designed for the first group based on a combined output observable condition. Then, a distributed event-triggered observer is proposed for the second group by employing the observer state of the first group. Based on the designed observers, adaptive controllers are derived for all subsystems. It is established that global stability of the closed loop system is ensured and asymptotic convergence of all the tracking errors is achieved. Moreover, a simulation example is provided to show the effectiveness of the proposed method.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • Linear Time-Invariant Discrete Delay Systems in Laguerre Domain

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      Authors: Alexander V. Medvedev;Viktor Bro;Rosane Ushirobira;
      Pages: 2677 - 2683
      Abstract: This article provides the formulas connecting the Laguerre spectrum of the output signal of a linear discrete-time time-invariant delay system to the Laguerre spectrum of its input signal. The Laguerre-domain system representation is meaningful when the input signal is square summable, and the system is stable. A certain type of polynomials arising in the evaluation of the output spectrum due to the presence of time delay is defined, and key properties of these are investigated. The polynomials are characterized by a three-term recurrence relation that also facilitates their numerically reliable calculation.
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
  • TechRxiv: Share Your Preprint Research with the World!

    • Free pre-print version: Loading...

      Pages: 2684 - 2684
      Abstract: Advertisement: TechRxiv is a free preprint server for unpublished research in electrical engineering, computer science, and related technology. TechRxiv provides researchers the opportunity to share early results of their work ahead of formal peer review and publication. Benefits: Rapidly disseminate your research findings; Gather feedback from fellow researchers; Find potential collaborators in the scientific community; Establish the precedence of a discovery; and Document research results in advance of publication. Upload your unpublished research today!
      PubDate: May 2022
      Issue No: Vol. 67, No. 5 (2022)
       
 
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