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  • Open Access

    ARTICLE

    Research on Stick-Slip Vibration Suppression Method of Drill String Based on Machine Learning Optimization

    Kanhua Su, Jian Wei*, Meng Li, Hao Li, Wenghao Da, Lang Zhang

    Sound & Vibration, Vol.57, pp. 97-117, 2023, DOI:10.32604/sv.2023.043734

    Abstract During the drilling process, stick-slip vibration of the drill string is mainly caused by the nonlinear friction generated by the contact between the drill bit and the rock. To eliminate the fatigue wear of downhole drilling tools caused by stick-slip vibrations, the Fractional-Order Proportional-Integral-Derivative (FOPID) controller is used to suppress stick-slip vibrations in the drill string. Although the FOPID controller can effectively suppress the drill string stick-slip vibration, its structure is flexible and parameter setting is complicated, so it needs to use the corresponding machine learning algorithm for parameter optimization. Based on the principle of torsional vibration, a simplified model… More > Graphic Abstract

    Research on Stick-Slip Vibration Suppression Method of Drill String Based on Machine Learning Optimization

  • Open Access

    ARTICLE

    Fractal Fractional Order Operators in Computational Techniques for Mathematical Models in Epidemiology

    Muhammad Farman1,2,4, Ali Akgül3,9,*, Mir Sajjad Hashemi5, Liliana Guran6,7, Amelia Bucur8,*

    CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.2, pp. 1385-1403, 2024, DOI:10.32604/cmes.2023.028803

    Abstract New fractional operators, the COVID-19 model has been studied in this paper. By using different numerical techniques and the time fractional parameters, the mechanical characteristics of the fractional order model are identified. The uniqueness and existence have been established. The model’s Ulam-Hyers stability analysis has been found. In order to justify the theoretical results, numerical simulations are carried out for the presented method in the range of fractional order to show the implications of fractional and fractal orders. We applied very effective numerical techniques to obtain the solutions of the model and simulations. Also, we present conditions of existence for… More >

  • Open Access

    ARTICLE

    Fractional Order Modeling of Predicting COVID-19 with Isolation and Vaccination Strategies in Morocco

    Lakhlifa Sadek1, Otmane Sadek1, Hamad Talibi Alaoui2, Mohammed S. Abdo3, Kamal Shah4,5, Thabet Abdeljawad4,6,*

    CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.2, pp. 1931-1950, 2023, DOI:10.32604/cmes.2023.025033

    Abstract In this work, we present a model that uses the fractional order Caputo derivative for the novel Coronavirus disease 2019 (COVID-19) with different hospitalization strategies for severe and mild cases and incorporate an awareness program. We generalize the SEIR model of the spread of COVID-19 with a private focus on the transmissibility of people who are aware of the disease and follow preventative health measures and people who are ignorant of the disease and do not follow preventive health measures. Moreover, individuals with severe, mild symptoms and asymptomatically infected are also considered. The basic reproduction number () and local stability… More >

  • Open Access

    ARTICLE

    On Nonlinear Conformable Fractional Order Dynamical System via Differential Transform Method

    Kamal Shah1,2, Thabet Abdeljawad3,4,*, Fahd Jarad5, Qasem Al-Mdallal6

    CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.2, pp. 1457-1472, 2023, DOI:10.32604/cmes.2023.021523

    Abstract This article studies a nonlinear fractional order Lotka-Volterra prey-predator type dynamical system. For the proposed study, we consider the model under the conformable fractional order derivative (CFOD). We investigate the mentioned dynamical system for the existence and uniqueness of at least one solution. Indeed, Schauder and Banach fixed point theorems are utilized to prove our claim. Further, an algorithm for the approximate analytical solution to the proposed problem has been established. In this regard, the conformable fractional differential transform (CFDT) technique is used to compute the required results in the form of a series. Using Matlab-16, we simulate the series… More >

  • Open Access

    ARTICLE

    Video Transmission Secrecy Improvement Based on Fractional Order Hyper Chaotic System

    S. Kayalvizhi*, S. Malarvizhi

    Computer Systems Science and Engineering, Vol.46, No.1, pp. 1201-1214, 2023, DOI:10.32604/csse.2023.032381

    Abstract In the Digital World scenario, the confidentiality of information in video transmission plays an important role. Chaotic systems have been shown to be effective for video signal encryption. To improve video transmission secrecy, compressive encryption method is proposed to accomplish compression and encryption based on fractional order hyper chaotic system that incorporates Compressive Sensing (CS), pixel level, bit level scrambling and nucleotide Sequences operations. The measurement matrix generates by the fractional order hyper chaotic system strengthens the efficiency of the encryption process. To avoid plain text attack, the CS measurement is scrambled to its pixel level, bit level scrambling decreases… More >

  • Open Access

    ARTICLE

    Study of Fractional Order Dynamical System of Viral Infection Disease under Piecewise Derivative

    Kamal Shah1,2, Hafsa Naz2, Thabet Abdeljawad1,3,*, Bahaaeldin Abdalla1

    CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.1, pp. 921-941, 2023, DOI:10.32604/cmes.2023.025769

    Abstract This research aims to understand the fractional order dynamics of the deadly Nipah virus (NiV) disease. We focus on using piecewise derivatives in the context of classical and singular kernels of power operators in the Caputo sense to investigate the crossover behavior of the considered dynamical system. We establish some qualitative results about the existence and uniqueness of the solution to the proposed problem. By utilizing the Newtonian polynomials interpolation technique, we recall a powerful algorithm to interpret the numerical findings for the aforesaid model. Here, we remark that the said viral infection is caused by an RNA type virus… More > Graphic Abstract

    Study of Fractional Order Dynamical System of Viral Infection Disease under Piecewise Derivative

  • Open Access

    ARTICLE

    Modifications of the Optimal Auxiliary Function Method to Fractional Order Fornberg-Whitham Equations

    Hakeem Ullah1, Mehreen Fiza1,*, Ilyas Khan2,*, Abd Allah A. Mosa3, Saeed Islam1, Abdullah Mohammed4

    CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.1, pp. 277-291, 2023, DOI:10.32604/cmes.2023.022289

    Abstract In this paper, we present a new modification of the newly developed semi-analytical method named the Optimal Auxilary Function Method (OAFM) for fractional-order equations using the Caputo operator, which is named FOAFM. The mathematical theory of FOAFM is presented and the effectiveness of this method is proven by using it with well-known Fornberg-Whitham Equations (FWE). The FOAFM results are compared with other method results along with their exact solutions with the help of tables and plots to prove the validity of FOAFM. A rapidly convergent series solution is obtained from FOAFM and is validated by comparison with other results. The… More >

  • Open Access

    ARTICLE

    Image Enhancement Using Adaptive Fractional Order Filter

    Ayesha Heena1,*, Nagashettappa Biradar1, Najmuddin M. Maroof2, Surbhi Bhatia3, Arwa Mashat4, Shakila Basheer5

    Computer Systems Science and Engineering, Vol.45, No.2, pp. 1409-1422, 2023, DOI:10.32604/csse.2023.029611

    Abstract Image enhancement is an important preprocessing task as the contrast is low in most of the medical images, Therefore, enhancement becomes the mandatory process before actual image processing should start. This research article proposes an enhancement of the model-based differential operator for the images in general and Echocardiographic images, the proposed operators are based on Grunwald-Letnikov (G-L), Riemann-Liouville (R-L) and Caputo (Li & Xie), which are the definitions of fractional order calculus. In this fractional-order, differentiation is well focused on the enhancement of echocardiographic images. This provoked for developing a non-linear filter mask for image enhancement. The designed filter is… More >

  • Open Access

    ARTICLE

    An Intelligence Computational Approach for the Fractional 4D Chaotic Financial Model

    Wajaree Weera1, Thongchai Botmart1,*, Charuwat Chantawat1, Zulqurnain Sabir2,3, Waleed Adel4,5, Muhammad Asif Zahoor Raja6, Muhammad Kristiawan7

    CMC-Computers, Materials & Continua, Vol.74, No.2, pp. 2711-2724, 2023, DOI:10.32604/cmc.2023.033233

    Abstract The main purpose of the study is to present a numerical approach to investigate the numerical performances of the fractional 4-D chaotic financial system using a stochastic procedure. The stochastic procedures mainly depend on the combination of the artificial neural network (ANNs) along with the Levenberg-Marquardt Backpropagation (LMB) i.e., ANNs-LMB technique. The fractional-order term is defined in the Caputo sense and three cases are solved using the proposed technique for different values of the fractional order α. The values of the fractional order derivatives to solve the fractional 4-D chaotic financial system are used between 0 and 1. The data… More >

  • Open Access

    ARTICLE

    A Neural Study of the Fractional Heroin Epidemic Model

    Wajaree Weera1, Thongchai Botmart1,*, Samina Zuhra2, Zulqurnain Sabir3, Muhammad Asif Zahoor Raja4, Salem Ben Said5

    CMC-Computers, Materials & Continua, Vol.74, No.2, pp. 4453-4467, 2023, DOI:10.32604/cmc.2023.033232

    Abstract This works intends to provide numerical solutions based on the nonlinear fractional order derivatives of the classical White and Comiskey model (NFD-WCM). The fractional order derivatives have provided authentic and accurate solutions for the NDF-WCM. The solutions of the fractional NFD-WCM are provided using the stochastic computing supervised algorithm named Levenberg-Marquard Backpropagation (LMB) based on neural networks (NNs). This regression approach combines gradient descent and Gauss-Newton iterative methods, which means finding a solution through the sequences of different calculations. WCM is used to demonstrate the heroin epidemics. Heroin has been on-growth world wide, mainly in Asia, Europe, and the USA.… More >

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