Article
Engineering, Multidisciplinary
Zhenghong Jin, Choon Ki Ahn, Jiawen Li
Summary: This study solves the distributed nonconvex optimization problem for nonlinear multi-agent systems over a weight-balanced and quasi-strongly connected graph. The goal is to steer all agents to the optimum of a given global objective function with partial information. Novel momentum-based distributed optimal coordinators are designed, and the local objective functions are required to be analytic. A system with different timescales is established to handle the interconnected closed-loop system. The proposed distributed method and extended algorithms are validated through numerical and application examples.
IEEE TRANSACTIONS ON NETWORK SCIENCE AND ENGINEERING
(2023)
Article
Biology
Justin Eilertsen, Santiago Schnell, Sebastian Walcher
Summary: In this study, we present a simplified model for the irreversible Michaelis-Menten reaction mechanism under quasi-steady-state conditions. We complement existing research by identifying local conditions that prevent quasi-steady-state reductions, both in the classical and broader sense. Furthermore, we discuss parameter regions where no quasi-steady-state reduction is applicable and show that these regions are small in a well defined sense. Additionally, we provide local conditions for the accuracy of standard or total quasi-steady-state.
MATHEMATICAL BIOSCIENCES
(2022)
Article
Automation & Control Systems
Madan Mohan Rayguru, Spandan Roy, Indra Narayan Kar
Summary: This article presents a saturated tracking controller based on a different theoretical framework, ensuring bounded tracking performance and quantifying steady-state error bounds in multi-input-multi-output nonlinear systems.
IEEE TRANSACTIONS ON SYSTEMS MAN CYBERNETICS-SYSTEMS
(2021)
Article
Electrochemistry
Leslaw K. Bieniasz, Michael Vynnycky, Sean McKee
Summary: This study introduces a novel integral equation-based modeling approach for describing reaction-diffusion processes in transient electrochemical experiments. By replacing the steady state assumption with a two-term singular perturbation expansion, this method can handle reaction-diffusion equations containing nonlinear reaction rate terms. The example simulation shows that this approach can successfully simulate homogeneous reactions with reaction rate constants that are one order of magnitude smaller than before.
ELECTROCHIMICA ACTA
(2022)
Article
Energy & Fuels
Andrzej J. Osiadacz, Malgorzata Kwestarz
Summary: This article describes a steady-state optimization algorithm for high-pressure gas networks to minimize compressor operating costs. Tests conducted on real network segments confirmed the algorithm's correctness and computational efficiency. Computational results obtained with the SQP method demonstrate the viability of this approach.
Article
Mathematics, Applied
Justin Eilertsen, Marc R. Roussel, Santiago Schnell, Sebastian Walcher
Summary: The conditions for the validity of the standard quasi-steady-state approximation in the Michaelis-Menten mechanism in a closed reaction vessel have been well studied, but much less so the conditions for the validity of this approximation for the system with substrate inflow. We analyze quasi-steady-state scenarios for the open system attributable to singular perturbations, as well as less restrictive conditions. Distinguished invariant manifolds and time scale estimates were obtained for both settings, with a highlight on the special role of singular perturbation parameters in higher order approximations of slow manifolds. The paper concludes with a discussion of distinguished invariant manifolds in the global phase portrait.
Article
Engineering, Aerospace
Zhaojun Pang, Hao Wen, Xiaoting Rui, Zhonghua Du
Summary: This paper studied the nonlinear resonant motions of a tethered satellite system in elliptical orbits using Lagrange's equations and the multiple scales method. It was found that internal resonance or combination resonance could occur in the system, but they did not occur simultaneously, with different bifurcation characteristics in the steady-state solutions. Poincare maps were employed to verify the analytical results.
Article
Energy & Fuels
Phuong H. Hoang, Gokhan Ozkan, Payam Ramezani Badr, Behnaz Papari, Christopher S. Edrington
Summary: This paper introduces a new algorithm for distributed constrained optimization problems, which constructs a dynamic system to seek global optimality and proves the semi-globally practical asymptotic stability of the system. Experimental results demonstrate the efficiency and practicality of the algorithm in real-time communication.
SUSTAINABLE ENERGY GRIDS & NETWORKS
(2021)
Article
Automation & Control Systems
Xiang Ren, Fei Hao
Summary: This paper investigates the application of observer-based event-triggered control in the stabilization of singularly perturbed systems. By designing two event-triggering conditions, ultimately bounded stability of the closed-loop system is achieved and Zeno behavior is eliminated.
Article
Green & Sustainable Science & Technology
Yongli Wang, Chen Liu, Chengcong Cai, Ziben Ma, Minhan Zhou, Huanran Dong, Fang Li
Summary: This study proposes a bi-level planning model for steady-state optimal configuration to achieve reasonable planning of urban energy structures. The model considers the steady-state relationships between energy systems and multiple energy sources, and utilizes nonlinear system dynamics and an improved optimization algorithm to solve the model. The results can provide guidance for planning decisions of urban energy systems.
Article
Thermodynamics
Catarina G. dos Santos, Julia P. Ruivo, Leticia B. Gasparini, Maria Thereza de M. G. Rosa, Darci Odloak, Miriam Tvrzska de Gouvea
Summary: This paper proposes a rigorous model for predicting the operation of an air cooled chiller in a large office building. It also presents simple correlations for predicting heat exchange coefficients and pressure drops. The rigorous model is shown to accurately predict the operation of the chiller and optimize energy consumption. The importance of considering evaporator pressure drop is emphasized.
CASE STUDIES IN THERMAL ENGINEERING
(2022)
Article
Mathematics, Applied
Jose M. Escorcia, Alexei A. Mailybaev
Summary: In this work, we conducted a systematic numerical study of the post-blowup dynamics of singular solutions of the 1D focusing critical NLS equation. The study showed that initially, the post-blowup can be described by the adiabatic approximation, but soon after the maximum of the solution, a non-adiabatic regime is observed. Our study also revealed that the non-adiabatic regime is caused by the increasing influx of mass into the collapsing core of the solution.
PHYSICA D-NONLINEAR PHENOMENA
(2023)
Article
Engineering, Electrical & Electronic
Qi Li, Dafang Wang, Jianhua Lin, Fangheng Jian, Zhifu Wang, Conggan Ma
Summary: This article proposes a new EME design method based on MIMO modeling and MCLCC structure, which can achieve dynamic accuracy objectives and robust performance at high operating speeds. Experimental results demonstrate the superiority of the proposed method.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2022)
Article
Mathematics, Applied
Dan Wei, Shangjiang Guo
Summary: This paper focuses on a nonlinear parabolic system with nonlinear boundary conditions. Different from previous work, we not only adopt two different inhomogeneous environmental carrying capacity functions, but also consider the generalized nonlinear behavior of species. By applying Lyapunov-Schmidt reduction and implicit function theorem, we obtain the existence of the spatial inhomogeneous steady-state solutions bifurcating from trivial solutions of the nonlinear system.
APPLIED MATHEMATICS LETTERS
(2022)
Article
Mathematics, Applied
Wen Lian, Zhanbing Bai
Summary: This article considers a class of singularly perturbed fourth order nonlinear differential equation, and investigates the existence of solutions to boundary value problem (BVP) without singularly perturbed using nonlinear analysis method and upper and lower solution theory. In addition, it examines the existence, uniqueness, and asymptotic estimation of the solution to singularly perturbed boundary value problem (SPBVP) based on differential inequality techniques and appropriate upper-lower solutions.
APPLIED MATHEMATICS LETTERS
(2021)
Article
Automation & Control Systems
Yu-kai Fu, Guang-Hong Yang, Hong-Jun Ma, Hao Chen, Bo Zhu
Summary: This article introduces a statistical fault diagnosis method that combines Kalman filter and generalized likelihood ratio test to detect fixture faults in the car body-in-white assembly process. The method accurately identifies the occurrence and location of faults, and effectively reduces false alarms and missed alarms.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Article
Automation & Control Systems
Xiu-Xiu Ren, Guang-Hong Yang, Xiao-Guang Zhang
Summary: This article presents the epsilon-stealthy attack against cyber-physical systems under the stochastic communication protocol (SCP) and aims to develop an optimal attack strategy. A novel attack model is proposed, and the analytical expression of the optimization problem is given. The results are validated through numerical simulations and experiments.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Article
Automation & Control Systems
Li-Ning Liu, Guang-Hong Yang
Summary: This article investigates the distributed push-pull gradient optimization algorithm over a directed communication network under false data injection attacks. The convergence of the algorithm under these attacks is analyzed, and conditions are provided to ensure convergence. Additionally, a distributed reputation-based neighborhood-observe strategy is proposed to detect and isolate malicious agents in the network. Unlike existing resilient strategies, this strategy completely eliminates the influence of false data on the algorithm, ensuring that the remaining normal agents can converge to the optimal solution. The effectiveness of the proposed strategy is validated through examples.
OPTIMAL CONTROL APPLICATIONS & METHODS
(2023)
Article
Automation & Control Systems
Xiu-Xiu Ren, Guang-Hong Yang
Summary: This article studies the filtering problem for a class of stochastic nonlinear system under non-Gaussian-Levy noise and cyber attacks. A modified Kalman filter is proposed to handle the extremely large values caused by the Levy noises and minimize the error covariance by designing filter parameters. In addition, convergence analysis of the filtering error and a boundedness condition for the upper bound are provided.
IEEE TRANSACTIONS ON SYSTEMS MAN CYBERNETICS-SYSTEMS
(2023)
Article
Automation & Control Systems
Jing-Jing Yan, Guang-Hong Yang, Xiao-Xu Liu
Summary: This article investigates the problem of secure state estimation for nonlinear industrial cyber-physical systems (ICPSs) with multiple transmission channels subject to denial-of-service (DoS) attacks. A new nonlinear resilient observer scheme is proposed using a multigain switching mechanism and Takagi-Sugeno fuzzy models, quantifying resilience by attack duration and frequency. Compared to existing results on linear ICPSs with single transmission channels, the secure estimation problem for nonlinear ICPSs with multiple channels is more challenging and has greater practical significance. The effectiveness of the scheme is illustrated through simulation and experimentation on a rigid robot system and a rotary inverted pendulum.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Article
Automation & Control Systems
Xiao-Guang Zhang, Guang-Hong Yang, Xiu-Xiu Ren
Summary: This article investigates stealthy attacks on cyber-physical systems using the stochastic communication protocol (SCP) to avoid data collisions. The attack's stealthiness is measured by the Kullback-Leibler divergence, and the attack performance is measured by the corrupted error covariance. The proposed attack strategy takes SCP-introduced effects into account and uses incomplete measurement outputs at each time instant to construct an attack model. A nonconvex optimization problem is formulated to achieve the desired attack performance for a given stealthy level. Analytical expressions for the attack parameters are derived, and simulations and experiments are conducted to validate the proposed theoretical results.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Article
Automation & Control Systems
Xiu-Xiu Ren, Guang-Hong Yang, Xiao-Guang Zhang
Summary: This article focuses on designing a strictly stealthy attack strategy against multisensor cyber-physical systems under the round-robin protocol. A novel protocol-based attack model is developed and an optimization problem is formulated to solve the optimal attack parameters. Experiments on a monitoring system are conducted to verify the results.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Article
Automation & Control Systems
Xiao-Guang Zhang, Guang-Hong Yang, Xiu-Xiu Ren
Summary: This article presents a design of stealthy attack against industrial cyber-physical systems using the random access protocol (RAP) to avoid data collisions. The goal is to develop an optimal attack that decreases the estimation performance while maintaining strict stealthiness. Due to the limitations of RAP, only a portion of transmitted data can be utilized for constructing attack signals, posing challenges to attack design. The article derives a novel modified algebraic Riccati equation (MARE) to establish the precondition for attack design, and a sufficient condition for the existence of the steady state of the modified Kalman filter is provided. The optimal attack strategy is obtained by solving a convex optimization problem, and analytical optimal attack parameters are presented and proven. Experiments and simulations are conducted to validate the findings.
IEEE TRANSACTIONS ON INDUSTRIAL INFORMATICS
(2023)
Article
Automation & Control Systems
Jing-Jing Yan, Guang-Hong Yang
Summary: This article focuses on secure state estimation for cyber-physical systems (CPSs) with nonlinear strict-feedback system models. The observer designed to receive the measured output over a wireless communication network is subject to denial-of-service (DoS) attacks. A novel multiobserver scheme and switched algorithm are proposed to improve estimation performance by introducing hold-input mechanism and cascade observer technique, overcoming the issue of unstable estimation error systems during attack intervals.
IEEE TRANSACTIONS ON CYBERNETICS
(2023)
Article
Automation & Control Systems
An-Yang Lu, Guang-Hong Yang
Summary: This article investigates the problem of attack detection and identification for cyber-physical systems under sparse sensor attacks. It proposes a novel candidate set construction algorithm to efficiently generate the candidate set containing all possible sets of corrupted channels. It also introduces a unified attack model and necessary and sufficient conditions for undetectable/unidentifiable attacks, and proposes a new attack detection and identification strategy.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2023)
Article
Automation & Control Systems
Xiang-Yu Kong, Guang-Hong Yang
Summary: This article investigates the problem of intrusion detection of stealthy false data injection (FDI) attacks in train-ground communication systems. An intrusion detection method is proposed based on the self-generated coding technology, improving the security of data transmission. Furthermore, a defence model is established to reconstruct the position information of compromised trains, and the effectiveness of the proposed method is verified through simulation experiments.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Article
Automation & Control Systems
Cheng-Yuan Sun, Guang-Hong Yang
Summary: This article introduces a hierarchical data-driven (HDD) method for quality-related fault diagnosis in industrial systems. The proposed approach uses ensemble learning to avoid selecting the optimal kernel parameter, reducing computation costs. Additionally, a novel quality-related fault diagnosis scheme is designed to monitor faults and reveal trends in the quality state. The effectiveness of the proposed method is demonstrated through simulation and industrial cases.
IEEE TRANSACTIONS ON INDUSTRIAL INFORMATICS
(2023)
Article
Automation & Control Systems
Li-Ning Liu, Guang-Hong Yang
Summary: This article studies the coordination economic dispatch problem for distributed energy resources, and proposes a switched distributed coordination algorithm to solve the problem over an unreliable communication network with DoS attacks. The algorithm integrates normal mode and attack mode, and limits the impact of attacks on convergence and optimality. It guarantees the exponential convergence of the algorithm under DoS attacks.
INTERNATIONAL JOURNAL OF SYSTEMS SCIENCE
(2023)
Article
Automation & Control Systems
Jipeng Zhao, Guang-Hong Yang
Summary: This article studies the problem of finite-time adaptive resilient control for MIMO nonlinear switched systems with unknown dead zone and unknown false data injection (FDI) attacks. A new coordinate transformation is designed to address the negative impact of FDI attacks, and the Nussbaum gain technique is introduced to deal with the difficulty of unknown time-varying weights caused by FDI attacks. A finite-time resilient control algorithm is designed based on the common Lyapunov function method, which ensures bounded signals of the closed-loop systems under arbitrary switching rules, even in the presence of unknown FDI attacks. The proposed control algorithm enables the controlled systems to reach an equilibrium state in a finite time and removes the assumption of positive attack weights. A practical simulation example demonstrates the validity of the designed control method.
IEEE TRANSACTIONS ON CYBERNETICS
(2023)
Article
Automation & Control Systems
Li-Ning Liu, Guang-Hong Yang, Saud Wasly
Summary: This article investigates the coordination dual-mode energy management problem for a microgrid, proposing a novel distributed algorithm that adaptively responds to mode switching and obtains optimal operation in a distributed way. Compared with existing algorithms, this algorithm has a predefined convergence time and an event-triggered communication strategy, greatly reducing communication resource consumption.
IEEE TRANSACTIONS ON INDUSTRIAL INFORMATICS
(2023)
