105 citations · 184 across the 36 of their papers we have counts for
38 papers
On the real angular stability radius for sectorial matrices
Sei Zhen Khong, Xin Mao, Li Qiu +1
The real stability radius problem asks for the smallest real perturbation that makes a given matrix lose rank, and it is a structured counterpart of the corresponding complex stabi…
Robust Instability Radius for Networked Dynamical Systems: Upper and Lower Bounds
Shinji Hara, Yutaka Hori, Tetsuya Iwasaki +2
This paper is concerned with robust instability of uncertain network systems. We consider the multi-agent system described as a network of single-input-single-output agents with id…
Exact Robust Instability Analysis for Networked Dynamical Systems with Biological Application
Shinji Hara, Yutaka Hori, Tetsuya Iwasaki +2
This paper investigates robust instability in nominally unstable uncertain networked dynamical systems, where all nominal agents share an identical single-input-single-output (SISO…
A Perron-Frobenius strong threshold theorem for (A, B, P, ϕ) balanced bilinear models, and the role of left and right Perron eigenvectors in mathematical epidemiology
Florin Avram, Rim Adenane, Andrei-Dan Halanay +2
This paper started as a review of seven results pertaining to a family of bilinear models with rank one NGM introduced by Fall, Iggidr, Sallet and Bonzi, which utilize the explicit…
Consensus in Plug-and-Play Heterogeneous Dynamical Networks: A Passivity Compensation Approach
Yongkang Su, Sei Zhen Khong, Lanlan Su
This paper investigates output consensus in heterogeneous dynamical networks within a plug-and-play framework. The networks are interconnected through nonlinear diffusive couplings…
Distance Between Stochastic Linear Systems
Venkatraman Renganathan, Sei Zhen Khong
While the existing stochastic control theory is well equipped to handle dynamical systems with stochastic uncertainties, a paradigm shift using distance measure based decision maki…
Passivity Compensation: A Distributed Approach for Consensus Analysis in Heterogeneous Networks
Yongkang Su, Sei Zhen Khong, Lanlan Su
This paper investigates a passivity-based approach to output consensus analysis in heterogeneous networks composed of non-identical agents coupled via nonlinear interactions, in th…
Soft and Hard Scaled Relative Graphs for Nonlinear Feedback Stability
Chao Chen, Sei Zhen Khong, Rodolphe Sepulchre
This article presents input-output stability analysis of nonlinear feedback systems based on the notion of soft and hard scaled relative graphs (SRGs). The soft and hard SRGs ackno…
On output consensus of heterogeneous dynamical networks
Yongkang Su, Lanlan Su, Sei Zhen Khong
This work is concerned with interconnected networks with non-identical subsystems. We investigate the output consensus of the network where the dynamics are subject to external dis…
Exact Instability Radius of Discrete-Time LTI Systems
Chung-Yao Kao, Sei Zhen Khong, Shinji Hara +1
The robust instability of an unstable plant subject to stable perturbations is of significant importance and arises in the study of sustained oscillatory phenomena in nonlinear sys…
Converse negative imaginary theorems
Sei Zhen Khong, Di Zhao, Alexander Lanzon
Converse negative imaginary theorems for linear time-invariant systems are derived. In particular, we provide necessary and sufficient conditions for a feedback system to be robust…
Steady-state analysis of networked epidemic models
Sei Zhen Khong, Lanlan Su
Compartmental epidemic models with dynamics that evolve over a graph network have gained considerable importance in recent years but analysis of these models is in general difficul…
On Phase Change Rate Maximization with Practical Applications
Chung-Yao Kao, Shinji Hara, Yutaka Hori +2
We recapitulate the notion of phase change rate maximization and demonstrate the usefulness of its solution on analyzing the robust instability of a cyclic network of multi-agent s…
Feedback Stability Analysis via Dissipativity with Dynamic Supply Rates
Sei Zhen Khong, Chao Chen, Alexander Lanzon
We propose a general notion of dissipativity with dynamic supply rates for nonlinear systems. This extends classical dissipativity with static supply rates and dynamic supply rates…
On the exponential convergence of input-output signals of nonlinear feedback systems
Lanlan Su, Di Zhao, Sei Zhen Khong
This note studies the exponential convergence of input-output signals of discrete-time nonlinear systems composed of a feedback interconnection of a linear time-invariant system an…
Gain and phase type multipliers for feedback robustness
Axel Ringh, Xin Mao, Wei Chen +2
It is known that the stability of a feedback interconnection of two linear time-invariant systems implies that the graphs of the open-loop systems are quadratically separated. This…
Exact Instability Margin Analysis and Minimum-Norm Strong Stabilization -- phase change rate maximization --
Shinji Hara, Chung-Yao Kao, Sei Zhen Khong +2
This paper is concerned with a new optimization problem named "phase change rate maximization" for single-input-single-output linear time-invariant systems. The problem relates to…
On the Necessity and Sufficiency of Discrete-Time O'Shea-Zames-Falb Multipliers
Lanlan Su, Peter Seiler, Joaquin Carrasco +1
This paper considers the robust stability of a discrete-time Lurye system consisting of the feedback interconnection between a linear system and a bounded and monotone nonlinearity…
A Frequency-Domain Approach to Nonlinear Negative Imaginary Systems Analysis
Di Zhao, Chao Chen, Sei Zhen Khong
In this study, we extend the theory of negative imaginary (NI) systems to a nonlinear framework using a frequency-domain approach. The extended notion is completely characterized v…
The Singular Angle of Nonlinear Systems
Chao Chen, Di Zhao, Sei Zhen Khong
In this paper, we introduce an angle notion called the singular angle for nonlinear systems from an input-output perspective. The proposed system singular angle, based on the angle…
A Phase Theory of MIMO LTI Systems
Wei Chen, Dan Wang, Sei Zhen Khong +1
In this paper, we define the phase response for a class of multi-input multi-output (MIMO) linear time-invariant (LTI) systems whose frequency responses are (semi-)sectorial at all…
Phase of Nonlinear Systems
Chao Chen, Di Zhao, Wei Chen +2
In this paper, we propose a definition of phase for a class of stable nonlinear systems called semi-sectorial systems, from an input-output perspective. The definition involves the…
Low Phase-Rank Approximation
Di Zhao, Axel Ringh, Li Qiu +1
In this paper, we propose and solve a low phase-rank approximation problem, which serves as a counterpart to the well-known low-rank approximation problem and the Schmidt-Mirsky th…
On Spectral Properties of Signed Laplacians with Connections to Eventual Positivity
Wei Chen, Dan Wang, Ji Liu +5
Signed graphs have appeared in a broad variety of applications, ranging from social networks to biological networks, from distributed control and computation to power systems. In t…