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Fractal and Fractional, Volume 6, Issue 1

2022 January - 48 articles

Cover Story: The scientific community has recently seen a fast-growing number of publications tackling the topic of fractional order controllers in general, with a focus on the fractional order PID. Very few recent papers discuss the practical use of such controllers. However, the industrial acceptance of these controllers is still far from being reached. Autotuning methods for such fractional order PIDs could possibly make them more appealing to industrial applications, as well. In this paper, the current autotuning methods for fractional order PIDs are reviewed. The focus is on the most recent findings. A comparison between several autotuning approaches is considered for various types of processes. Numerical examples are given to highlight the practicality of the methods that could be extended to simple industrial processes. View this paper
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Articles (48)

  • Article
  • Open Access
4 Citations
2,830 Views
8 Pages

Third Hankel Determinant for a Subclass of Univalent Functions Associated with Lemniscate of Bernoulli

  • Najeeb Ullah,
  • Irfan Ali,
  • Sardar Muhammad Hussain,
  • Jong-Suk Ro,
  • Nazar Khan and
  • Bilal Khan

This paper deals with a new subclass of univalent function associated with the right half of the lemniscate of Bernoulli. We find the upper bound of the Hankel determinant H3(1) for this subclass by applying the Carlson–Shaffer operator to it....

  • Article
  • Open Access
12 Citations
3,370 Views
17 Pages

A Look-Up Table Based Fractional Order Composite Controller Synthesis Method for the PMSM Speed Servo System

  • Weijia Zheng,
  • Runquan Huang,
  • Ying Luo,
  • YangQuan Chen,
  • Xiaohong Wang and
  • Yong Chen

Considering the performance requirements in actual applications, a look-up table based fractional order composite control scheme for the permanent magnet synchronous motor speed servo system is proposed. Firstly, an extended state observer based comp...

  • Article
  • Open Access
2 Citations
2,526 Views
11 Pages

There are very few papers that talk about the global convergence of iterative methods with the help of Banach spaces. The main purpose of this paper is to discuss the global convergence of third order iterative method. The convergence analysis of thi...

  • Article
  • Open Access
11 Citations
2,475 Views
27 Pages

We introduce a new class of boundary value problems consisting of a q-variant system of Langevin-type nonlinear coupled fractional integro-difference equations and nonlocal multipoint boundary conditions. We make use of standard fixed-point theorems...

  • Article
  • Open Access
3 Citations
2,926 Views
19 Pages

Maximum Likelihood Estimation for Mixed Fractional Vasicek Processes

  • Chun-Hao Cai,
  • Yin-Zhong Huang,
  • Lin Sun and
  • Wei-Lin Xiao

In this paper, we consider the problem of estimating the drift parameters in the mixed fractional Vasicek model, which is an extended model of the traditional Vasicek model. Using the fundamental martingale and the Laplace transform, both the strong...

  • Article
  • Open Access
26 Citations
3,351 Views
22 Pages

Some Novel Fractional Integral Inequalities over a New Class of Generalized Convex Function

  • Soubhagya Kumar Sahoo,
  • Muhammad Tariq,
  • Hijaz Ahmad,
  • Bibhakar Kodamasingh,
  • Asif Ali Shaikh,
  • Thongchai Botmart and
  • Mohammed A. El-Shorbagy

The comprehension of inequalities in convexity is very important for fractional calculus and its effectiveness in many applied sciences. In this article, we handle a novel investigation that depends on the Hermite–Hadamard-type inequalities con...

  • Article
  • Open Access
40 Citations
3,736 Views
21 Pages

The nonlocal boundary value problem, dtρu(t)+Au(t)=f(t) (0<ρ<1, 0<tT), u(ξ)=αu(0)+φ (α is a constant and 0<ξT), in an arbitrary separable Hilbert space H with the strongly positive selfadjoint operato...

  • Article
  • Open Access
76 Citations
6,440 Views
20 Pages

Currently, low heat Portland (LHP) cement is widely used in mass concrete structures. The magnesia expansion agent (MgO) can be adopted to reduce the shrinkage of conventional Portland cement-based materials, but very few studies can be found that in...

  • Article
  • Open Access
3 Citations
5,861 Views
23 Pages

Self-similar sets with the open set condition, the linear objects of fractal geometry, have been considered mainly for crystallographic data. Here we introduce new symmetry classes in the plane, based on rotation by irrational angles. Examples withou...

  • Article
  • Open Access
26 Citations
3,592 Views
28 Pages

Fractional derivatives have been proven to showcase a spectrum of solutions that is useful in the fields of engineering, medical, and manufacturing sciences. Studies on the application of fractional derivatives on fluid flow are relatively new, espec...

  • Review
  • Open Access
72 Citations
6,124 Views
25 Pages

A Review of Recent Developments in Autotuning Methods for Fractional-Order Controllers

  • Cristina I. Muresan,
  • Isabela Birs,
  • Clara Ionescu,
  • Eva H. Dulf and
  • Robin De Keyser

The scientific community has recently seen a fast-growing number of publications tackling the topic of fractional-order controllers in general, with a focus on the fractional order PID. Several versions of this controller have been proposed, includin...

  • Article
  • Open Access
23 Citations
2,509 Views
28 Pages

This research paper deals with the passivity and synchronization problem of fractional-order memristor-based competitive neural networks (FOMBCNNs) for the first time. Since the FOMBCNNs’ parameters are state-dependent, FOMBCNNs may exhibit unexpecte...

  • Article
  • Open Access
52 Citations
3,724 Views
15 Pages

This paper studies the analytical solutions of the fractional fluid models described by the Caputo derivative. We combine the Fourier sine and the Laplace transforms. We analyze the influence of the order of the Caputo derivative the Prandtl number,...

  • Article
  • Open Access
21 Citations
2,628 Views
10 Pages

Simpson’s Second-Type Inequalities for Co-Ordinated Convex Functions and Applications for Cubature Formulas

  • Sabah Iftikhar,
  • Samet Erden,
  • Muhammad Aamir Ali,
  • Jamel Baili and
  • Hijaz Ahmad

Inequality theory has attracted considerable attention from scientists because it can be used in many fields. In particular, Hermite–Hadamard and Simpson inequalities based on convex functions have become a cornerstone in pure and applied mathe...

  • Article
  • Open Access
33 Citations
3,544 Views
12 Pages

In this paper, nonlinear nonautonomous equations with the generalized proportional Caputo fractional derivative (GPFD) are considered. Some stability properties are studied by the help of the Lyapunov functions and their GPFDs. A scalar nonlinear fra...

  • Article
  • Open Access
19 Citations
3,032 Views
26 Pages

In this work, we present a modified generalized Mittag–Leffler function method (MGMLFM) and Laplace Adomian decomposition method (LADM) to get an analytic-approximate solution for nonlinear systems of partial differential equations (PDEs) of fr...

  • Article
  • Open Access
16 Citations
2,327 Views
23 Pages

On Starlike Functions of Negative Order Defined by q-Fractional Derivative

  • Sadia Riaz,
  • Ubaid Ahmed Nisar,
  • Qin Xin,
  • Sarfraz Nawaz Malik and
  • Abdul Raheem

In this paper, two new classes of q-starlike functions in an open unit disc are defined and studied by using the q-fractional derivative. The class Sq*˜(α), α(3,1], q(0,1) generalizes the class Sq* of q-starlike f...

  • Article
  • Open Access
35 Citations
3,163 Views
21 Pages

Discretization, Bifurcation, and Control for a Class of Predator-Prey Interactions

  • Asifa Tassaddiq,
  • Muhammad Sajjad Shabbir,
  • Qamar Din and
  • Humera Naaz

The present study focuses on the dynamical aspects of a discrete-time Leslie-Gower predator-prey model accompanied by a Holling type III functional response. Discretization is conducted by applying a piecewise constant argument method of differential...

  • Article
  • Open Access
20 Citations
2,173 Views
14 Pages

In this study, a novel design of a second kind of nonlinear Lane–Emden prediction differential singular model (NLE-PDSM) is presented. The numerical solutions of this model were investigated via a neuro-evolution computing intelligent solver us...

  • Article
  • Open Access
3 Citations
1,988 Views
15 Pages

In the literature of mathematical inequalities, convex functions of different kinds are used for the extension of classical Hadamard inequality. Fractional integral versions of the Hadamard inequality are also studied extensively by applying Riemann&...

  • Article
  • Open Access
17 Citations
3,392 Views
22 Pages

The Role of the Discount Policy of Prepayment on Environmentally Friendly Inventory Management

  • Shirin Sultana,
  • Abu Hashan Md Mashud,
  • Yosef Daryanto,
  • Sujan Miah,
  • Adel Alrasheedi and
  • Ibrahim M. Hezam

Nowadays, more and more consumers consider environmentally friendly products in their purchasing decisions. Companies need to adapt to these changes while paying attention to standard business systems such as payment terms. The purpose of this study...

  • Review
  • Open Access
23 Citations
7,254 Views
31 Pages

Recent Advances and Applications of Spiral Dynamics Optimization Algorithm: A Review

  • Madiah Binti Omar,
  • Kishore Bingi,
  • B Rajanarayan Prusty and
  • Rosdiazli Ibrahim

This paper comprehensively reviews the spiral dynamics optimization (SDO) algorithm and investigates its characteristics. SDO algorithm is one of the most straightforward physics-based optimization algorithms and is successfully applied in various br...

  • Article
  • Open Access
26 Citations
2,742 Views
11 Pages

In this article, a new method for obtaining closed-form solutions of the simplified modified Camassa-Holm (MCH) equation, a nonlinear fractional partial differential equation, is suggested. The modified Riemann-Liouville fractional derivative and the...

  • Article
  • Open Access
10 Citations
2,535 Views
16 Pages

In this paper, the solvability of a system of nonlinear Caputo fractional differential equations at resonance is considered. The interesting point is that the state variable xRn and the effect of the coefficient matrices matrices B and C of bou...

  • Article
  • Open Access
1 Citations
1,947 Views
12 Pages

The Lieb concavity theorem, successfully solved in the Wigner–Yanase–Dyson conjecture, is an important application of matrix concave functions. Recently, the Thompson–Golden theorem, a corollary of the Lieb concavity theorem, was ex...

  • Article
  • Open Access
10 Citations
4,244 Views
9 Pages

Background: solute transport in highly heterogeneous media and even neutron diffusion in nuclear environments are among the numerous applications of fractional differential equations (FDEs), being demonstrated by field experiments that solute concent...

  • Article
  • Open Access
25 Citations
2,981 Views
27 Pages

The article discusses different schemes for the numerical solution of the fractional Riccati equation with variable coefficients and variable memory, where the fractional derivative is understood in the sense of Gerasimov-Caputo. For a nonlinear frac...

  • Article
  • Open Access
29 Citations
4,407 Views
23 Pages

Effect of Chemical Composition of Fine Aggregate on the Frictional Behavior of Concrete–Soil Interface under Sulfuric Acid Environment

  • Jie Xiao,
  • Zhenming Xu,
  • Yikang Murong,
  • Lei Wang,
  • Bin Lei,
  • Lijing Chu,
  • Haibo Jiang and
  • Wenjun Qu

Through direct shear tests, this paper aimed to research the effect of fine marble aggregate on the shear strength and fractal dimension of the interface between soil and concrete corroded by sulfuric acid. More realistic concrete rough surfaces than...

  • Article
  • Open Access
2 Citations
1,923 Views
18 Pages

In this work, we explore the existence results for the hybrid Caputo–Hadamard fractional boundary value problem (CH-FBVP). The inclusion version of the proposed BVP with a three-point hybrid Caputo–Hadamard terminal conditions is also considered and...

  • Article
  • Open Access
5 Citations
2,393 Views
20 Pages

We investigate the existence and multiplicity of positive solutions for a system of Riemann–Liouville fractional differential equations with r-Laplacian operators and nonnegative singular nonlinearities depending on fractional integrals, supple...

  • Article
  • Open Access
13 Citations
2,981 Views
19 Pages

We propose a fractional-order shifted Jacobi–Gauss collocation method for variable-order fractional integro-differential equations with weakly singular kernel (VO-FIDE-WSK) subject to initial conditions. Using the Riemann–Liouville fracti...

  • Article
  • Open Access
6 Citations
2,488 Views
13 Pages

The coupled cubic-quintic nonlinear Schrödinger (CQNLS) equation is a universal mathematical model describing many physical situations, such as nonlinear optics and Bose–Einstein condensate. In this paper, in order to simplify the process...

  • Article
  • Open Access
30 Citations
3,176 Views
17 Pages

In this paper, three new models of fractal–fractional Michaelis–Menten enzymatic reaction (FFMMER) are studied. We present these models based on three different kernels, namely, power law, exponential decay, and Mittag-Leffler kernels. We...

  • Article
  • Open Access
18 Citations
2,898 Views
17 Pages

Synchronization of Fractional Order Uncertain BAM Competitive Neural Networks

  • M. Syed Ali,
  • M. Hymavathi,
  • Syeda Asma Kauser,
  • Grienggrai Rajchakit,
  • Porpattama Hammachukiattikul and
  • Nattakan Boonsatit

This article examines the drive-response synchronization of a class of fractional order uncertain BAM (Bidirectional Associative Memory) competitive neural networks. By using the differential inclusions theory, and constructing a proper Lyapunov-Kras...

  • Article
  • Open Access
1,567 Views
11 Pages

In this paper, a dissipative version of the Benjamin–Ono dynamics is shown to faithfully model the collective evolution of swarms of scalar Cauchy stochastic agents obeying a follow-the-leader interaction rule. Due to the Hilbert transform, the...

  • Article
  • Open Access
2 Citations
2,920 Views
14 Pages

In this paper, the concept of F-contraction was generalized for cone metric spaces over topological left modules and some fixed point results were obtained for self-mappings satisfying a contractive condition of this type. Some applications of the ma...

  • Article
  • Open Access
10 Citations
4,279 Views
15 Pages

The aim of this paper is to establish the existence and uniqueness results for differential equations of Hilfer-type fractional order with variable coefficient. Firstly, we establish the equivalent Volterra integral equation to an initial value probl...

  • Article
  • Open Access
9 Citations
5,602 Views
26 Pages

In this paper, we consider numerical solutions for a general form of fractional delay differential equations (FDDEs) with fractional derivatives defined in the Caputo sense. A fractional integration operational matrix, created using a fractional Tayl...

  • Article
  • Open Access
2 Citations
2,822 Views
13 Pages

The advection–dispersion equations have gotten a lot of theoretical attention. The difficulty in dealing with these problems stems from the fact that there is no perfect answer and that tackling them using local numerical methods is tough. The...

  • Article
  • Open Access
3 Citations
3,586 Views
12 Pages

A Quantum Wavelet Uncertainty Principle

  • Sabrine Arfaoui,
  • Maryam G. Alshehri and
  • Anouar Ben Mabrouk

In the present paper, an uncertainty principle is derived in the quantum wavelet framework. Precisely, a new uncertainty principle for the generalized q-Bessel wavelet transform, based on some q-quantum wavelet, is established. A two-parameters exten...

  • Article
  • Open Access
18 Citations
4,738 Views
14 Pages

Solutions of General Fractional-Order Differential Equations by Using the Spectral Tau Method

  • Hari Mohan Srivastava,
  • Daba Meshesha Gusu,
  • Pshtiwan Othman Mohammed,
  • Gidisa Wedajo,
  • Kamsing Nonlaopon and
  • Y. S. Hamed

Here, in this article, we investigate the solution of a general family of fractional-order differential equations by using the spectral Tau method in the sense of Liouville–Caputo type fractional derivatives with a linear functional argument. W...

  • Article
  • Open Access
1 Citations
2,820 Views
12 Pages

Relevance of Factorization Method to Differential and Integral Equations Associated with Hybrid Class of Polynomials

  • Naeem Ahmad,
  • Raziya Sabri,
  • Mohammad Faisal Khan,
  • Mohammad Shadab and
  • Anju Gupta

This article has a motive to derive a new class of differential equations and associated integral equations for some hybrid families of Laguerre–Gould–Hopper-based Sheffer polynomials. We derive recurrence relations, differential equation...

  • Article
  • Open Access
35 Citations
3,088 Views
16 Pages

Some Hadamard–Fejér Type Inequalities for LR-Convex Interval-Valued Functions

  • Muhammad Bilal Khan,
  • Savin Treanțǎ,
  • Mohamed S. Soliman,
  • Kamsing Nonlaopon and
  • Hatim Ghazi Zaini

The purpose of this study is to introduce the new class of Hermite–Hadamard inequality for LR-convex interval-valued functions known as LR-interval Hermite–Hadamard inequality, by means of pseudo-order relation ( p ). This o...

  • Article
  • Open Access
198 Citations
5,458 Views
12 Pages

In this article, we construct the exact dynamical wave solutions to the Date–Jimbo–Kashiwara–Miwa equation with conformable derivative by using an efficient and well-established approach, namely: the two-variable G/G, &n...

  • Article
  • Open Access
15 Citations
3,926 Views
23 Pages

In the present work, the numerical solution of fractional delay integro-differential equations (FDIDEs) with weakly singular kernels is addressed by designing a Vieta–Fibonacci collocation method. These equations play immense roles in scientifi...

  • Article
  • Open Access
10 Citations
3,457 Views
19 Pages

Semidefinite Multiobjective Mathematical Programming Problems with Vanishing Constraints Using Convexificators

  • Kin Keung Lai,
  • Mohd Hassan,
  • Sanjeev Kumar Singh,
  • Jitendra Kumar Maurya and
  • Shashi Kant Mishra

In this paper, we establish Fritz John stationary conditions for nonsmooth, nonlinear, semidefinite, multiobjective programs with vanishing constraints in terms of convexificator and introduce generalized Cottle type and generalized Guignard type con...

  • Article
  • Open Access
43 Citations
4,148 Views
26 Pages

In this study, we depicted the spread of pests in tea plants and their control by biological enemies in the frame of a fractional-order model, and its dynamics are surveyed in terms of boundedness, uniqueness, and the existence of the solutions. To r...

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Fractal Fract. - ISSN 2504-3110