Results 21 to 30 of about 1,907 (143)

Performance improvement of discrete‐time linear‐quadratic regulators applied to uncertain linear systems using the Tikhonov regularization method

Asian Journal of Control, EarlyView.
Abstract The linear‐quadratic regulator (LQR) problem of optimal control of an uncertain discrete‐time linear system (DTLS) is revisited in this paper from the perspective of Tikhonov regularization. We show that an optimally chosen regularization parameter reduces, compared to the classical LQR, the values of a scalar error function, as well as the ...
Fernando Pazos, Amit Bhaya
wiley   +1 more source

A hidden Markov model and reinforcement learning‐based strategy for fault‐tolerant control

The Canadian Journal of Chemical Engineering, EarlyView.
Abstract This study introduces a data‐driven control strategy integrating hidden Markov models (HMM) and reinforcement learning (RL) to achieve resilient, fault‐tolerant operation against persistent disturbances in nonlinear chemical processes. Called hidden Markov model and reinforcement learning (HMMRL), this strategy is evaluated in two case studies
Tamera Leitao, Debaprasad Dutta, Simant R. Upreti   +2 more
wiley   +1 more source

On subset least squares estimation and prediction in vector autoregressive models with exogenous variables

Canadian Journal of Statistics, EarlyView.
Abstract We establish the consistency and the asymptotic distribution of the least squares estimators of the coefficients of a subset vector autoregressive process with exogenous variables (VARX). Using a martingale central limit theorem, we derive the asymptotic normal distribution of the estimators. Diagnostic checking is discussed using kernel‐based
Pierre Duchesne, Thanh‐Liem Huynh, Mylène Oscar   +2 more
wiley   +1 more source

A trek rule for the Lyapunov equation

Algebraic Statistics
The Lyapunov equation is a linear matrix equation characterizing the cross-sectional steady-state covariance matrix of a Gaussian Markov process. We show a new version of the trek rule for this equation, which links the graphical structure of the drift of the process to the entries of the steady-state covariance matrix.
openaire   +2 more sources

Mathematical Analysis and Simulations of a Cancer Model With Interleukins and Delayed Immunotherapy

Mathematical Methods in the Applied Sciences, EarlyView.
ABSTRACT A new system of delayed differential equations for tumor‐immune system interactions is proposed and studied. The system describes the interactions between tumor cells and the immune system at the most aggressive phase of cancer, where tumor cells have developed mechanisms from earlier stages to evade immune responses.
Laid Boudjellal, Ana Jacinta Soares, Maria Joana Torres   +2 more
wiley   +1 more source

Analysis of a Novel Time‐Continuous Dimer Growth Model Describing One Possible Cause of Alzheimer's Disease and a Time‐Discretization for Its Numerical Simulation

Mathematical Methods in the Applied Sciences, EarlyView.
ABSTRACT Because oligomers of the amyloid‐β$$ \beta $$ (Aβ$$ A\beta $$) protein can possibly be regarded as one main cause for progressive development of Alzheimer's disease, different mathematical models for its emergence have been proposed by different scientific groups.
Benjamin Wacker
wiley   +1 more source

T(w)o Patch or Not T(w)o Patch: A Novel Biocontrol Model

Mathematical Methods in the Applied Sciences, EarlyView.
ABSTRACT A number of top‐down biocontrol models have been proposed where the introduced predators' efficacy is enhanced via the provision of additional food (AF). However, if the predator has a pest‐dependent monotone functional response, pest extinction is unattainable. In the current manuscript, we propose a model where a predator with pest‐dependent
Urvashi Verma, Aniket Banerjee, Rana D. Parshad   +2 more
wiley   +1 more source

Fractional Moment Theory for Anomalous Transport: A Unified Framework for Lévy Flights, Fractals, and Complex Dynamical Systems

Mathematical Methods in the Applied Sciences, EarlyView.
ABSTRACT We develop a unified mathematical framework extending classical moment theory from discrete integer orders to a continuous spectrum of real orders f>0$$ f>0 $$, providing a systematic statistical characterization of complex systems exhibiting power‐law behavior.
Farrukh A. Chishtie
wiley   +1 more source

A Comprehensive Multistage Average Controller for Trajectory Tracking in Solar‐Powered Mobile Robots: Analysis of Actuator‐Driver and Power Stage Integration

International Journal of Mechanical System Dynamics, EarlyView.
ABSTRACT This work addresses the challenge of bidirectional trajectory tracking in solar‐powered wheeled mobile robots (WMRs), considering the mechanical structure, actuator‐driver, and power stage subsystems. Notably, this is the first study to explicitly model and control the actuator‐driver subsystem within this context. The proposed solution relies
Benjamin Natanael Santiago‐Nogales, Julio Cesar Ordaz‐Dehesa, Ramón Silva‐Ortigoza, Erik Reyes‐Reyes, J. Martín Alba‐Martínez, Juan Eduardo Velázquez‐Velázquez, José Rafael García‐Sánchez, Magdalena Marciano‐Melchor, Hind Taud   +8 more
wiley   +1 more source

Robust Position Control of an Electro‐Hydraulic Actuator via Metaheuristic Optimization of a Fractional‐Order PID Controller

International Journal of Mechanical System Dynamics, EarlyView.
ABSTRACT In this study, a robust position control strategy is presented for a two‐stage electro‐hydraulic actuator system using a fractional‐order proportional–integral–derivative (FOPID) controller tuned by Kirchhoff's law algorithm (KLA). Electro‐hydraulic systems exhibit strong nonlinearities, parameter uncertainties, and external disturbances ...
Ridvan Firat Cinar, Davut Izci, Serdar Ekinci, Mohammad Salman, Mohammad Al‐Rabayah, Ali Akdagli, Ali Yildiz, Filiz Karaomerlioglu, Gökhan Yüksek   +8 more
wiley   +1 more source