Browsing by Author "Razminia, Abolhassan"

Now showing 1 - 9 of 9

Chaotic Incommensurate Fractional Order Rossler System: Active Control and Synchronization
(Springer, 2011) Razminia, Abolhassan; Baleanu, Dumitru; Majd, Vahid Johari; Baleanu, Dumitru; 56389
In this article, we present an active control methodology for controlling the chaotic behavior of a fractional order version of Rossler system. The main feature of the designed controller is its simplicity for practical implementation. Although in controlling such complex system several inputs are used in general to actuate the states, in the proposed design, all states of the system are controlled via one input. Active synchronization of two chaotic fractional order Rossler systems is also investigated via a feedback linearization method. In both control and synchronization, numerical simulations show the efficiency of the proposed methods.
Complete synchronization of commensurate fractional order chaotic systems using sliding mode control
(Pergamon-elsevier Science Ltd, 2013) Razminia, Abolhassan; Baleanu, Dumitru; Baleanu, Dumitru; 56389
In this manuscript, we consider a new fractional order chaotic system which exhibits interesting behavior such as two, three, and four scrolls. Such systems can be found extensively in mechatronics and power electronic systems which exhibit self-sustained oscillations. Synchronization between two such systems is an interesting problem either theoretically or practically. Using a sliding mode control methodology, we synchronize a unidirectional coupling structure for the two chaotic systems. Numerical simulations are used to verify the theoretical analysis. Additionally, we report the robustness of the system in the presence of a noise in simulation. (C) 2013 Elsevier Ltd. All rights reserved.
Conditional Optimization Problems: Fractional Order Case
(Springer/plenum Publishers, 2013) Razminia, Abolhassan; Baleanu, Dumitru; Baleanu, Dumitru; Majd, Vahid Johari
In this manuscript, we introduce a new formulation for the constrained optimization problems in which the objective function is considered in the fractional integral form. The constraints are applied in two separate cases, namely, fractional differential and fractional isoperimetric constraints. In both cases, by using the extended Euler-Lagrange equations and the Lagrange multiplier method, the necessary conditions are obtained. An example is given in order to illustrate the effectiveness of the reported results.
Fractal-fractional modelling of partially penetrating wells
(Pergamon-Elsevier Science LTD, 2019) Baleanu, Dumitru; Razminia, Abolhassan; Baleanu, Dumitru; 56389
In this paper, the fractional order dynamical system theory is used to describe the complex behaviour of partially penetrating wells (PPWs) in a typical reservoir whose geometry is governed by fractal tools. The Green's function approach, as a generalised impulse response function, is adopted to model the fluid flow in any type of reservoir with a partially penetrating (vertical) well producing from it. Having obtained the initial description of a typical PPW, using the Laplace transform a new dimensionless constant-flow-rate solution is introduced, when wellbore storage and skin effects are significant. The pressure-transient behaviour of a PPW is discussed following two synthetic examples which illustratively depict the effectiveness of the proposed results. (C) 2019 Elsevier Ltd. All rights reserved.
Fractional hyperchaotic telecommunication systems: A new paradigm
(Asme, 2013) Razminia, Abolhassan; Baleanu, Dumitru; Baleanu, Dumitru; 56389
The dynamics of hyperchaotic and fractional-order systems have increasing attracted attention in recent years. In this paper, we mix two complex dynamics to construct a new telecommunication system. Using a hyperchaotic fractional order system, we propose a novel synchronization scheme between receiver and transmitter which increases the security of data transmission and communication. Indeed, this is first work that can open a new way in secure communication system.
Fractional order models of industrial pneumatic controllers
(2014) Baleanu, Dumitru; Baleanu, Dumitru; 56389
This paper addresses a new approach for modeling of versatile controllers in industrial automation and process control systems such as pneumatic controllers. Some fractional order dynamical models are developed for pressure and pneumatic systems with bellows-nozzle-flapper configuration. In the light of fractional calculus, a fractional order derivative-derivative (FrDD) controller and integral-derivative (FrID) are remodeled. Numerical simulations illustrate the application of the obtained theoretical results in simple examples. © 2014 Abolhassan Razminia and Dumitru Baleanu.
Fractional synchronization of chaotic systems with different orders
(Editura Acad Romane, 2012) Baleanu, Dumitru; Baleanu, Dumitru
In this paper, we consider two chaotic systems with different orders. First, we consider the case when one of them is fractional order (master system) and another one is integer order (slave system). Second, we consider the case when both of them are fractional order but the orders are different. Using a fractional synchronization scheme in the presence of discrepancy between initial conditions of these systems for both cases the trajectories of the slave system are forced to track the master system trajectories. The effectiveness of the proposed technique is verified by numerical simulations for Chen systems
Investigation of The Fractional Diffusion Equation Based on Generalized Integral Quadrature Technique
(Elsevier Science inc, 2015) Razminia, Kambiz; Baleanu, Dumitru; Razminia, Abolhassan; Baleanu, Dumitru; 56389
Nowadays, the conventional Euclidean models are mostly used to describe the behavior of fluid flow through porous media. These models assume the homogeneity of the reservoir, and in naturally fractured reservoir, the fractures are distributed uniformly and use the interconnected fractures assumption. However, several cases such as core, log, outcrop data, production behavior of reservoirs, and the dynamic behavior of reservoirs indicate that the reservoirs have a different behavior other than these assumptions in most cases. According to the fractal theory and the concept of fractional derivative, a generalized diffusion equation is presented to analyze the transport in fractal reservoirs. Three outer boundary conditions are investigated. Using exact analytical or semi-analytical solutions for generalized diffusion equation with fractional order differential equation and a fractal physical form, under the usual assumptions, requires large amounts of computation time and may produce inaccurate and fake results for some combinations of parameters. Because of fractionality, fractal shape, and therefore the existence of infinite series, large computation times occur, which is sometimes slowly convergent. This paper provides a computationally efficient and accurate method via differential quadrature (DQ) and generalized integral quadrature (GIQ) analyses of diffusion equation to overcome these difficulties. The presented method would overcome the imperfections in boundary conditions' implementations of second-order partial differential equation (PDE) encountered in such problems. (C) 2014 Elsevier Inc. All rights reserved.
Optimal Control of a MIMO Bioreactor System Using Direct Approach
(2021) Baleanu, Dumitru; Razminia, Abolhassan; Mobayen, Saleh; Baleanu, Dumitru; 56389
In this paper, the optimal control of a continuous type bioreactor with multi-input-multi-output signals is presented for the two active phases: growth and stationary. The underlying criterion to be minimized generalizes the classic quadratic forms to address some crucial objectives in controlling the bioreactor. In particular, the protection of actuators against fast switching in the controller output is considered by including a weighting term of the control signal derivatives. The direct optimal control approach is used to carry out the optimization in the presence of various limiting constraints. Direct methods are based on transcribing the infinite-dimensional problem to a finite-dimensional one. In this manuscript, direct single shooting and trapezoidal collocation methods are used for transcription, and the successive quadratic programming method is employed to solve the resulting nonlinear programming problem. It is shown that the trapezoidal method is an effective method for controlling the bioreactor in all the active phases, whereas the single shooting fails in dealing with the unstable one (i.e., growth). To analyze solutions in a more accurate manner, an auxiliary criterion is defined, and then the cheap control analysis is studied. The convergence to the lowest value of the auxiliary cost function and the effects on the optimal state and control trajectories are then examined by varying cheap parameters. Several numerical simulations support the presented theoretical formulation.