Weiping Luo^1,2, Dajun Yuan^1,2, Dalong Jin^1,2,*, Ping Lu^1,2, Jian Chen³

CMES-Computer Modeling in Engineering & Sciences, Vol.128, No.1, pp. 109-127, 2021, DOI:10.32604/cmes.2021.015683

Abstract The control of slurry pressure aiming to be consistent with the external water and earth pressure during shield tunnelling has great significance for face stability, especially in urban areas or underwater where the surrounding environment is very sensitive to the fluctuation of slurry pressure. In this study, an optimal control method for slurry pressure during shield tunnelling is developed, which is composed of an identifier and a controller. The established identifier based on the random forest (RF) can describe the complex non-linear relationship between slurry pressure and its influencing factors. The proposed controller based on particle swarm optimization (PSO) can… More >

Amr M. S. Mahdy^1,2,*, Mahmoud Higazy^1,3, Mohamed S. Mohamed^1,4

CMC-Computers, Materials & Continua, Vol.67, No.3, pp. 3463-3486, 2021, DOI:10.32604/cmc.2021.015161

Abstract In this article, the reduced differential transform method is introduced to solve the nonlinear fractional model of Tumor-Immune. The fractional derivatives are described in the Caputo sense. The solutions derived using this method are easy and very accurate. The model is given by its signal flow diagram. Moreover, a simulation of the system by the Simulink of MATLAB is given. The disease-free equilibrium and stability of the equilibrium point are calculated. Formulation of a fractional optimal control for the cancer model is calculated. In addition, to control the system, we propose a novel modification of its model. This modification is… More >

Ibrahim M. Hezam^1,2,*

CMC-Computers, Materials & Continua, Vol.67, No.1, pp. 1153-1167, 2021, DOI:10.32604/cmc.2021.014710

Abstract Since COVID-19 was declared as a pandemic in March 2020, the world’s major preoccupation has been to curb it while preserving the economy and reducing unemployment. This paper uses a novel Bi-Level Dynamic Optimal Control model (BLDOC) to coordinate control between COVID-19 and unemployment. The COVID-19 model is the upper level while the unemployment model is the lower level of the bi-level dynamic optimal control model. The BLDOC model’s main objectives are to minimize the number of individuals infected with COVID-19 and to minimize the unemployed individuals, and at the same time minimizing the cost of the containment strategies. We… More >

Isa Abdullahi Baba^1,*, Bashir Ahmad Nasidi¹, Dumitru Baleanu^2,3,4

CMC-Computers, Materials & Continua, Vol.66, No.3, pp. 3089-3106, 2021, DOI:10.32604/cmc.2021.012301

Abstract As the corona virus (COVID-19) pandemic ravages socio-economic activities in addition to devastating infectious and fatal consequences, optimal control strategy is an effective measure that neutralizes the scourge to its lowest ebb. In this paper, we present a mathematical model for the dynamics of COVID-19, and then we added an optimal control function to the model in order to effectively control the outbreak. We incorporate three main control efforts (isolation, quarantine and hospitalization) into the model aimed at controlling the spread of the pandemic. These efforts are further subdivided into five functions; u₁(t) (isolation of the susceptible communities), u₂(t) (contact… More >

Viorel Minzu^*, Adrian Serbencu

Intelligent Automation & Soft Computing, Vol.26, No.4, pp. 663-677, 2020, DOI:10.32604/iasc.2020.010101

Abstract The idea for this work starts from the situation in which a metaheuristic-based algorithm has already been developed in order to solve an optimal control problem. This algorithm yields an offline "optimal" solution. On the other hand, the Receding Horizon Control (RHC) structure can be implemented if a process model is available. This work underlines some of the practical aspects of joining the RHC to an existing metaheuristic-based algorithm in order to obtain a closed-loop control structure that can be further used in real-time control. The result is a systematic procedure that integrates a given metaheuristic-based algorithm into a RHC… More >

Hong-Sen Yan^1,2, Jiao-Jun Zhang^1,2, Qi-Ming Sun^1,2

Intelligent Automation & Soft Computing, Vol.25, No.3, pp. 487-507, 2019, DOI:10.31209/2018.100000037

Abstract MTN optimal control scheme of SISO nonlinear time-varying discrete-time systems based on multi-dimensional Taylor network (MTN) is proposed to achieve the real-time output tracking control for a given reference signal. Firstly, an ideal output signal is selected and Pontryagin minimum principle adopted to obtain the numerical solution of the optimal control law for the system relative to the ideal output signal, with the corresponding optimal output termed as desired output signal. Then, MTN optimal controller (MTNC) is generated automatically to fit the optimal control law, and the conjugate gradient (CG) method is employed to train the weight parameters of MTNC… More >

Abd-Allah Hyder^{1, 2, *}, M. El-Badawy³

CMC-Computers, Materials & Continua, Vol.64, No.2, pp. 859-870, 2020, DOI:10.32604/cmc.2020.09897

Abstract In this paper, the non-stationary incompressible fluid flows governed by the Navier-Stokes equations are studied in a bounded domain. This study focuses on the timefractional Navier-Stokes equations in the optimal control subject, where the control is distributed within the domain and the time-fractional derivative is proposed as RiemannLiouville sort. In addition, the control object is to minimize the quadratic cost functional. By using the Lax-Milgram lemma with the assistance of the fixed-point theorem, we demonstrate the existence and uniqueness of the weak solution to this system. Moreover, for a quadratic cost functional subject to the time-fractional Navier-Stokes equations, we prove… More >

Cheinshan Liu^{1, 2}, Chunglun Kuo¹, Jiangren Chang^{3, *}

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.1, pp. 33-48, 2020, DOI:10.32604/cmes.2020.08490

Abstract In the optimal control problem of nonlinear dynamical system, the Hamiltonian formulation is useful and powerful to solve an optimal control force. However, the resulting Euler-Lagrange equations are not easy to solve, when the performance index is complicated, because one may encounter a two-point boundary value problem of nonlinear differential algebraic equations. To be a numerical method, it is hard to exactly preserve all the specified conditions, which might deteriorate the accuracy of numerical solution. With this in mind, we develop a novel algorithm to find the solution of the optimal control problem of nonlinear Duffing oscillator, which can exactly… More >

Satoshi Ii^1,*, Keisuke Ito¹, Naoya Takakusaki¹, Naoya Sakamoto¹

Molecular & Cellular Biomechanics, Vol.16, Suppl.2, pp. 49-49, 2019, DOI:10.32604/mcb.2019.07378

Abstract Cells adhere to a substrate and generate traction forces in focal adhesions that enable them to apprehend extracellular mechanical properties [1]. Current concerns are focused on mechanisms how the mechanical balances hold in the cell and affect the cell behavior, and therefore non-invasive measurement techniques for the cell traction forces are required. The cell traction force microscopy (TFM) generalized by Dembo and Wang [2] is an attractive approach to non-invasively estimate cell traction force fields, in which an inverse problem is solved using a mechanical model of the substrate and displacement fields from fluorescent images of immersed beads in the… More >

A. M. Mughal¹, K. Iqbal²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.6, No.4, pp. 215-220, 2008, DOI:10.3970/icces.2008.006.215

Abstract Human voluntary movements are complex physical phenomenon and there are several physiological factors that control the movement and transient response, steady state position, speed of motion and other characteristics. Many experimentalists described variety of variables important for human balance and movement such as center of mass, center of pressure, ground reaction forces etc. In this study, we discuss a bipedal model for biomechanical sit to stand movement with optimal controller design. The cost optimization for gain scheduling is based upon physiological variables of center of mass, head position, and ground reaction forces. Our simulation results shows that movement profiles improve… More >