Magdi S Mahmoud
KFUPM, Systems Engineering, Faculty Member
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In this paper, we examine the robust H∞ filtering problem for linear, uncertain multi-state-delay systems with Markovian jump parameters. The uncertainties are time-varying and norm-bounded parametric uncertainties and the delay factor is... more
In this paper, we examine the robust H∞ filtering problem for linear, uncertain multi-state-delay systems with Markovian jump parameters. The uncertainties are time-varying and norm-bounded parametric uncertainties and the delay factor is arbitrary time-varying. We provide initially a robust stochastic stability result with a prescribed performance measure. Then we design a linear casual filter using linear matrix inequality procedure, which
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A new delay-dependent criterion is developed for robust stability of linear discrete-time singular systems with state-delay and parametric uncertainties. The time-delay is varying between known bounds and the uncertainties are assumed to... more
A new delay-dependent criterion is developed for robust stability of linear discrete-time singular systems with state-delay and parametric uncertainties. The time-delay is varying between known bounds and the uncertainties are assumed to be time-invariant and norm-bounded appearing in the state and delay matrices. The new criterion is achieved by an expanded state-space system representation. A solution to delay-dependent stabilization is attained based on guaranteed cost and H� control approaches. All the developed results are conveniently cast in the format of linear matrix inequalities (LMIs) and numerical examples are presented.
This paper addresses the feedback control design problem for a wide class of discrete-time systems possessing fast and slow modes. The slow and fast subsystems are considered to be completely controllable and observable. Based on the H∞... more
This paper addresses the feedback control design problem for a wide class of discrete-time systems possessing fast and slow modes. The slow and fast subsystems are considered to be completely controllable and observable. Based on the H∞ optimization criteria, a two-stage design procedure is developed using separate gain matrices for the fast and slow subsystems and computed using linear matrix inequalities. A composite control is designed to yield first-order approximations to the behavior of the discrete system. A typical application is presented to illustrate the design procedure.
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Page 1. A two-stage output feedback design Prof. MS Mahmoud, M.Sc, Ph.D., C.Eng., Sen.Mem.IEEE, MIEE, Y. Chen, B.Sc, M.Eng., and Prof. MG Singh, Ph.D., D.Sc, C.Eng., Sen.Mem.IEEE, FIEE Indexing terms: Feedback, Modelling, Matrix algebra,... more
Page 1. A two-stage output feedback design Prof. MS Mahmoud, M.Sc, Ph.D., C.Eng., Sen.Mem.IEEE, MIEE, Y. Chen, B.Sc, M.Eng., and Prof. MG Singh, Ph.D., D.Sc, C.Eng., Sen.Mem.IEEE, FIEE Indexing terms: Feedback, Modelling, Matrix algebra, Design ...
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This paper studies robust stability, stabilization, andH∞control for a class of nonlinear discrete time stochastic systems. Firstly, the easily testing criteria for stochastic stability and stochastic stabilizability are obtained via... more
This paper studies robust stability, stabilization, andH∞control for a class of nonlinear discrete time stochastic systems. Firstly, the easily testing criteria for stochastic stability and stochastic stabilizability are obtained via linear matrix inequalities (LMIs). Then a robustH∞state feedback controller is designed such that the concerned system not only is internally stochastically stabilizable but also satisfies robustH∞performance. Moreover, the previous results of the nonlinearly perturbed discrete stochastic system are generalized to the system with state, control, and external disturbance dependent noise simultaneously. Two numerical examples are given to illustrate the effectiveness of the proposed results.
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In this article a fuzzy logic turbine governor is designed and simulated for the control of a hydraulic turbine, together with its penstock, based on a nonlinear turbine model. The designed fuzzy logic governor can be used in hydropower... more
In this article a fuzzy logic turbine governor is designed and simulated for the control of a hydraulic turbine, together with its penstock, based on a nonlinear turbine model. The designed fuzzy logic governor can be used in hydropower plants, and may replace the commonly used classical PID turbine governors that are causing instability problems.
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... (email: qiujiqing@263.net. Magdi S. Mahmoud is with the Systems Engineering Department, KFUPM, PO Box 985, Dhahran 31261, Saudi Arabia. ... Ai(t) = Ai + ΔAi(t), Adi(t) = Adi + ΔAdi(t) Bi(t) = Bi + ΔBi(t), Ci(t) = Ci + ΔCi(t) Cdi(t) =... more
... (email: qiujiqing@263.net. Magdi S. Mahmoud is with the Systems Engineering Department, KFUPM, PO Box 985, Dhahran 31261, Saudi Arabia. ... Ai(t) = Ai + ΔAi(t), Adi(t) = Adi + ΔAdi(t) Bi(t) = Bi + ΔBi(t), Ci(t) = Ci + ΔCi(t) Cdi(t) = Cdi + ΔCdi(t), Di(t) = Di + ΔDi(t) Hi(t) = Hi + ΔHi(t) ...
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The analysis of the stochastic stability of fault tolerant control systems (FTCS) has been considered using Lyapunov function approach. A new dynamical model is developed to overcome the limitations of the existing results. In this model,... more
The analysis of the stochastic stability of fault tolerant control systems (FTCS) has been considered using Lyapunov function approach. A new dynamical model is developed to overcome the limitations of the existing results. In this model, two independent failure processes with Markovian transition probabilities are considered: one for plant components and the other for control actuators. Moreover, the proposed model takes into consideration failures in control actuators with internal dynamics. It is shown that the exponential stability in the mean square is sufficient for the almost sure asymptotic stability, and a necessary and sufficient condition for the exponential stability in the mean square for linear FTCS is derived. Some previously known results are shown to be special cases of these new results. A numerical example is included to demonstrate the theoretical analysis
Research Interests: Independent Component Analysis, Markov Processes, Control Systems, Fault Tolerance, Stochastic processes, and 10 moreFault Tolerant Control, Actuators, Stability Analysis, Theoretical Analysis, Lyapunov function, Asymptotic Stability, Ftcs, dynamic model, Exponential Stability, and transition probability
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ABSTRACT This paper introduces a model-free reinforcement learning technique that is used to solve a class of dynamic games known as dynamic graphical games. The graphical game results from multi-agent dynamical systems, where pinning... more
ABSTRACT This paper introduces a model-free reinforcement learning technique that is used to solve a class of dynamic games known as dynamic graphical games. The graphical game results from multi-agent dynamical systems, where pinning control is used to make all the agents synchronize to the state of a command generator or a leader agent. Novel coupled Bellman equations and Hamiltonian functions are developed for the dynamic graphical games. The Hamiltonian mechanics are used to derive the necessary conditions for optimality. The solution for the dynamic graphical game is given in terms of the solution to a set of coupled Hamilton-Jacobi-Bellman equations developed herein. Nash equilibrium solution for the graphical game is given in terms of the solution to the underlying coupled Hamilton-Jacobi-Bellman equations. An online model-free policy iteration algorithm is developed to learn the Nash solution for the dynamic graphical game. This algorithm does not require any knowledge of the agents’ dynamics. A proof of convergence for this multi-agent learning algorithm is given under mild assumption about the inter-connectivity properties of the graph. A gradient descent technique with critic network structures is used to implement the policy iteration algorithm to solve the graphical game online in real-time.
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The networked control system (NCS) design for continuous-time systems with probabilistic delays is discussed in this paper. The delay is assumed to follow a given probability density function. A novel design scheme for the output feedback... more
The networked control system (NCS) design for continuous-time systems with probabilistic delays is discussed in this paper. The delay is assumed to follow a given probability density function. A novel design scheme for the output feedback controller is developed to render the closed-loop networked system exponentially mean-square stable with \( H_{\infty } \) performance requirement. A numerical example is provided to show the advantages of the proposed technique.
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An integral part of deterministic and stochastic dynamical models describing physical and man-made systems can be conveniently cast into the framework of time-delay systems TDs, that is a wide class of retarded or neutral differential... more
An integral part of deterministic and stochastic dynamical models describing physical and man-made systems can be conveniently cast into the framework of time-delay systems TDs, that is a wide class of retarded or neutral differential equations containing state and/or input delays [81, 93]. It becomes increasingly apparent that delays occur due to various reasons including finite capabilities of information processing among different parts of the system, inherent phenomena like mass transport flow and recycling and/or by product of computational delays [81]. Considerable discussions on delays and their stabilization/ destabilization effects in control systems have commanded the interests of numerous investigators in recent years, see [22, 52, 78, 79, 86, 87, 89, 90, 95] and the references cited therein.
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This paper introduces novel model-free adaptive learning algorithm to solve the dynamic graphical games in real-time. It allows online model-free tuning of the controller and critic networks. This algorithm solves the dynamic graphical... more
This paper introduces novel model-free adaptive learning algorithm to solve the dynamic graphical games in real-time. It allows online model-free tuning of the controller and critic networks. This algorithm solves the dynamic graphical game in a distributed fashion. Novel coupled Bellman equations and Hamiltonian functions are developed for the dynamic graphical games. Nash solution for the dynamic graphical game is given in terms of the solution to a set of coupled Hamilton-Jacobi-Bellman equations developed herein. An online model-free policy iteration algorithm is developed to learn the Nash solution for the dynamic graphical game in real-time. A proof of convergence for this algorithm is given under mild assumptions about the inter-connectivity properties of the graph.
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Research Interests: Robust control, Fuzzy Systems, Fuzzy Control, Numerical Simulation, Linear Matrix Inequalities, and 11 moreQuantization, Stability Analysis, Robustness, Fuzzy System, Delays, Networked Control System (NCS), Fuzzy Controller, Asymptotic Stability, Linear Matrix Inequality, Discrete time, and Symmetric Matrices
An integrated treatment of the techniques of systems control analysis, components, and design with emphasis on the role of computing elements for problems and examples drawn from diverse fields, including chemical, mechanical, biological,... more
An integrated treatment of the techniques of systems control analysis, components, and design with emphasis on the role of computing elements for problems and examples drawn from diverse fields, including chemical, mechanical, biological, ecological, and sociological systems. Specifically, the volum
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A global exponential stability method for a class of discrete time recurrent neural networks with interval time-varying delays and norm-bounded time-varying parameter uncertainties is developed in this paper. The method is derived based... more
A global exponential stability method for a class of discrete time recurrent neural networks with interval time-varying delays and norm-bounded time-varying parameter uncertainties is developed in this paper. The method is derived based on a new Lyapunov-Krasovskii functional to exhibit the delay-range-dependent dynamics and to compensate for the enlarged time-span. In addition, it eliminates the need for over bounding and utilizes smaller number of LMI decision variables. Effective solutions to the global stability problem are provided in terms of feasibility-testing of parameterized linear matrix inequalities (LMIs). Numerical examples are presented to demonstrate the potential of the developed technique.
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A decision support model based on stream flow ensemble forecasts has been developed for the Lower Colorado River Authority in Central Texas, and predictive skill is added to climatology-based forecasts by conditioning the ensembles on... more
A decision support model based on stream flow ensemble forecasts has been developed for the Lower Colorado River Authority in Central Texas, and predictive skill is added to climatology-based forecasts by conditioning the ensembles on observable climate indicators. These indicators include stream flow (persistence), soil moisture, and large-scale recurrent patterns such as the El Nino-Southern Oscillation, Pacific Decadal Oscillation, and
Research Interests: North Atlantic Oscillation, Water Management, Seasonality, Water Supply, Reservoir Operation, and 10 moreSoil moisture, Decision Support, Colorado River, El Nino-Southern Oscillation, Correlation Analysis, Large Scale, Variable Infiltration Capacity Model, Ensemble Forecasting, Pacific Decadal Oscillation, and Stream Flow
ABSTRACT A linearized version of a recently developed water quality dynamic model of the River Nile is considered. Two control strategies are designed in a decentralized way to optimally adjusting the concentration of water quality... more
ABSTRACT A linearized version of a recently developed water quality dynamic model of the River Nile is considered. Two control strategies are designed in a decentralized way to optimally adjusting the concentration of water quality constituents. Simulation results of the decentralized control structure are presented.
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This paper addresses the problems of adaptive identification and control for a class of interconnected systems where the parameters of the subsystems as well as the coupling matrices are unknown. At first, an adaptive scheme is proposed... more
This paper addresses the problems of adaptive identification and control for a class of interconnected systems where the parameters of the subsystems as well as the coupling matrices are unknown. At first, an adaptive scheme is proposed to identify the parameters of the interconnected system; moreover, if the inputs are persistently exciting, it is established that the identified parameters converge to their true values. The identified parameters of the system are then used in the design of both a state regulation scheme and a state tracking scheme for the interconnected system. Simulation results are given to illustrate the developed theory.
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... Abdulla Ismail Magdi S. Mahmoud ... where A f is the incremental frequency deviation (Hz), AP,, is the increniental change in turbine output (pu MW), AI', is thc incrcrncntal change in reheat tur-bine output (Pu MW), AP, is... more
... Abdulla Ismail Magdi S. Mahmoud ... where A f is the incremental frequency deviation (Hz), AP,, is the increniental change in turbine output (pu MW), AI', is thc incrcrncntal change in reheat tur-bine output (Pu MW), AP, is the incremental change in governor valve position (pu MW ...
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In this chapter, we provide a short overview of a number of results of \(\mathcal{H}_{2}\) and \(\mathcal{H}_{\infty}\) theories with an eye to using them for control system design. We discuss various methods of robust feedback control... more
In this chapter, we provide a short overview of a number of results of \(\mathcal{H}_{2}\) and \(\mathcal{H}_{\infty}\) theories with an eye to using them for control system design. We discuss various methods of robust feedback control schemes and demonstrate their applications to typical practical systems.
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In this chapter, the problem of designing decentralized adaptive state feedback controllers with corresponding adaptive law is presented a class of nonlinear time-varying and time-delay interconnected systems. Coordinate-free geometric... more
In this chapter, the problem of designing decentralized adaptive state feedback controllers with corresponding adaptive law is presented a class of nonlinear time-varying and time-delay interconnected systems. Coordinate-free geometric conditions under which any general interconnected nonlinear system can be transformed to decentralized strict feedback form are developed. In addition, a digital redesign of the analogue model-reference-based decentralized adaptive tracker is constructed for the sampled-data large scale system consisting of N interconnected linear subsystems, so that the system output will follow any trajectory specified at sampling instants.
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In this chapter, the problem of Kalman filtering for a class of switched systems with state delays is investigated. Both discrete-time and continuous-time representations are treated. In both cases, attention is focused on the design of a... more
In this chapter, the problem of Kalman filtering for a class of switched systems with state delays is investigated. Both discrete-time and continuous-time representations are treated. In both cases, attention is focused on the design of a stable filter guaranteeing a prescribed noise attenuation level in the \({\cal H}_{\infty}\) sense. By using an appropriate switched estimation scheme, sufficient conditions for the solvability of this problem are obtained in terms of algebraic Riccatti equations (AREs), which, when solved, a desired \({\cal H}_{\infty}\) filter can be constructed.
Overhead crane systems play a vital role in different factories to transport heavy loads. This paper provides an overview of recent developments in the modeling and control of three-dimensional overhead crane systems. It provides a... more
Overhead crane systems play a vital role in different factories to transport heavy loads. This paper provides an overview of recent developments in the modeling and control of three-dimensional overhead crane systems. It provides a categorized survey of the published work. Different control methodologies when applied to overhead crane are examined, outlined and assessed to aid for future work.