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SOME NEW TYPES OF GRONWALL-BELLMAN INEQUALITY ON FRACTAL SET Fractals (IF 4.7) Pub Date : 2024-04-20 GUOTAO WANG, RONG LIU
Gronwall–Bellman-type inequalities provide a very effective way to investigate the qualitative and quantitative properties of solutions of nonlinear integral and differential equations. In recent years, local fractional calculus has attracted the attention of many researchers. In this paper, based on the basic knowledge of local fractional calculus and the method of proving inequality on the set of
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INTELLIGENT EXTRACTION OF COMPLEXITY TYPES IN FRACTAL RESERVOIR AND ITS SIGNIFICANCE TO ESTIMATE TRANSPORT PROPERTY Fractals (IF 4.7) Pub Date : 2024-04-20 YI JIN, BEN ZHAO, YUNHANG YANG, JIABIN DONG, HUIBO SONG, YUNQING TIAN, JIENAN PAN
Fractal pore structure exists widely in natural reservoir and dominates its transport property. For that, more and more effort is devoted to investigate the control mechanism on mass transfer in such a complex and multi-scale system. Apparently, effective characterization of the fractal structure is of fundamental importance. Although the newly emerged concept of complexity assembly clarified the complexity
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BOX DIMENSION OF FRACTAL INTERPOLATION SURFACES WITH VERTICAL SCALING FUNCTION Fractals (IF 4.7) Pub Date : 2024-04-20 LAI JIANG
In this paper, we first present a simple lemma which allows us to estimate the box dimension of graphs of given functions by the associated oscillation sums and oscillation vectors. Then we define vertical scaling matrices of generalized affine fractal interpolation surfaces (FISs). By using these matrices, we establish relationships between oscillation vectors of different levels, which enables us
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Commensurations of Aut(FN) and Its Torelli Subgroup Geom. Funct. Anal. (IF 2.2) Pub Date : 2024-04-22 Martin R. Bridson, Richard D. Wade
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Dark energy stars in f(R,G) gravity Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-04-18 Krishna Pada Das, Ujjal Debnath
In this paper, we have provided a discussion regarding the structural properties of a spherical compact stellar object within the background of f(R,G) modified gravity. We have considered that the interior region of the compact stellar body is filled by a composition of anisotropic dark energy and isotropic normal matter which are assumed to be non-interacting. To relate the two stated fluids, we have
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Deflection angle and shadow evolution from charged torus-like black hole under the effect of non-magnetic plasma and non-plasma medium Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-04-18 Riasat Ali, Xia Tiecheng, Muhammad Awais, Rimsha Babar
In this study, we investigate the deflection angle of a torus-like regular charged black hole in the limit approximation of a weak field to check the effects of non-magnetic plasma and non-plasma medium. Using spacetime optical geometry, we first compute the Gaussian optical curvature. We study the light deflection angle from a charged torus-like black hole using the Gibbons and Werner approach. By
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Little Rip and Pseudo Rip Cosmological Models with Coupled Dark Energy Based on a New Generalized Entropy Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-04-18 I. Brevik, A. V. Timoshkin
In this paper, we study Little Rip (LR) and Pseudo Rip (PR) cosmological models containing two coupled fluids: dark energy and dark matter. We assume a spatially flat Friedmann–Robertson–Walker (FRW) universe. The interaction between the dark energy and the dark matter fluid components is described in terms of the parameters in the generalized Equation of State (EoS) in presence of the bulk viscosity
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Sections and Unirulings of Families over $\mathbb{P}^{1}$ Geom. Funct. Anal. (IF 2.2) Pub Date : 2024-04-18 Alex Pieloch
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On the N-waves hierarchy with constant boundary conditions. Spectral properties Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-04-13 Vladimir S. Gerdjikov, Georgi G. Grahovski
This paper is devoted to N-wave equations with constant boundary conditions related to symplectic Lie algebras. We study the spectral properties of a class of Lax operators L, whose potentials Q(x,t) tend to constants Q± for x→±∞. For special choices of Q±, we outline the spectral properties of L, the direct scattering transform and construct its fundamental analytic solutions. We generalize Wronskian
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Exploring the deceleration parameter in f(T) gravity: A comprehensive analysis using parametrization techniques and observational data Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-04-13 Himanshu Chaudhary, Amine Bouali, Hülya Duru, Ertan Güdekli, G. Mustafa
In this paper, we employ parametrization techniques within the framework of f(T) gravity to investigate the deceleration parameter (DP), a key quantity characterizing the universe’s expansion dynamics. By analyzing the DP, we gain valuable insights into the nature of cosmic constituents and their impact on the universe’s evolution. We utilize a combination of observational data, including 31 Cosmic
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Perfect fluid locally rotationally symmetric Bianchi Type-I spacetimes admitting concircular vector fields in f(T) gravity Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-04-13 Suhail Khan, Syed Majid Shah, Ahmad Tawfik Ali, Sameerah Jamal
We obtained the solutions of Einstein’s Field Equations (EFEs) for locally rotationally symmetric (LRS) Bianchi type-I perfect fluid spacetimes through the concircular vector fields (CCVFs) in f(T) gravity. It is shown that such metrics admit CCVFs of 4, 5, 6, 7, 8 and 15 dimensions. We also calculated the energy density, fluid pressure, torsion scalar T and the form of the function f(T). We did not
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A study of mixed super quasi-Einstein manifolds with applications to general relativity Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-04-13 Mohd Vasiulla, Mohabbat Ali, İnan Ünal
In this paper, we explore a set of geometric properties of Mixed Super Quasi-Einstein (MSQE) manifolds and provide examples of both Riemannian and Lorentzian MSQE manifolds to demonstrate their existence. Furthermore, we examine MSQE spacetimes in the context of the space-matter tensor, discussing several related properties. Finally, we establish the existence of an MSQE spacetime through a nontrivial
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ATTACK VULNERABILITY OF FRACTAL SCALE-FREE NETWORK Fractals (IF 4.7) Pub Date : 2024-04-13 FEIYAN GUO, LIN QI, YING FAN
An in-depth analysis of the attack vulnerability of fractal scale-free networks is of great significance for designing robust networks. Previous studies have mainly focused on the impact of fractal property on attack vulnerability of scale-free networks under static node attacks, while we extend the study to the cases of various types of targeted attacks, and explore the relationship between the attack
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A NEW PERSPECTIVE ON THE NONLINEAR DATE–JIMBO–KASHIWARA–MIWA EQUATION IN FRACTAL MEDIA Fractals (IF 4.7) Pub Date : 2024-04-12 JIANSHE SUN
In this paper, we first created a fractal Date–Jimbo–Kashiwara–Miwa (FDJKM) long ripple wave model in a non-smooth boundary or microgravity space recorded. Using fractal semi-inverse skill (FSIS) and fractal traveling wave transformation (FTWT), the fractal variational principle (FVP) was derived, and the strong minimum necessary circumstance was attested with the He Wierstrass function. We have discovered
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Dominated Splitting from Constant Periodic Data and Global Rigidity of Anosov Automorphisms Geom. Funct. Anal. (IF 2.2) Pub Date : 2024-04-15 Jonathan DeWitt, Andrey Gogolev
We show that a \(\operatorname{GL}(d,\mathbb{R})\) cocycle over a hyperbolic system with constant periodic data has a dominated splitting whenever the periodic data indicates it should. This implies global periodic data rigidity of generic Anosov automorphisms of \(\mathbb{T}^{d}\). Further, our approach also works when the periodic data is narrow, that is, sufficiently close to constant. We can show
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Characterization of a special type of Ricci–Bourguignon soliton on sequential warped product manifold Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-04-10 Sampa Pahan, Souvik Dutta
In this paper, we aim to characterize the sequential warped product κ-almost gradient conformal Ricci–Bourguignon soliton. We derive applications of some vector fields like conformal vector field, torse-forming vector field, torqued vector field on κ-almost conformal Ricci–Bourguignon soliton. The inheritance properties of the Einstein-like sequential warped product κ-almost gradient conformal Ricci–Bourguignon
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Dark energy and dark matter as a kinematic-electromagnetic Abelian gauge effect Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-04-10 Alcides Garat
In this paper, we will discuss an alternative theory for the origin of dark matter and dark energy based on the new concept of tetrad gauge states of spacetime. The new tetrads already introduced new physics since it has been proved that local electromagnetic gauge transformations can boost the local tetrad fields in a four-dimensional curved Lorentz spacetime. It is within this context that we will
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A comparative study on the maximum mass and radius of anisotropic compact stars from Heintzmann geometry and the TOV approach Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-04-10 B. Das, K. B. Goswami, P. K. Chattopadhyay
In this paper, a class of anisotropic compact stars is analyzed in Heintzmann geometry. The Einstein field equations (EFEs) have been solved to obtain the stellar model in presence of pressure anisotropy. We have considered the gtt metric component as proposed by Heintzmann, and by solving the EFEs, the grr metric component is evaluated in the presence of pressure anisotropy. It is noted that for an
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Binary Darboux transformation of vector nonlocal reverse-space nonlinear Schrödinger equations Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-04-10 Wen-Xiu Ma, Yehui Huang, Fudong Wang, Yong Zhang, Liyuan Ding
For vector nonlocal reverse-space nonlinear Schrödinger equations, a binary Darboux transformation is formulated by using two sets of eigenfunctions and adjoint eigenfunctions. The resulting binary Darboux transformation has been decomposed into an N-fold product of single binary Darboux transformations. An application starting from zero seed potentials generates a class of soliton solutions.
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A FRACTAL-BASED OIL TRANSPORT MODEL WITH UNCERTAINTY REDUCTION FOR A MULTI-SCALE SHALE PORE SYSTEM Fractals (IF 4.7) Pub Date : 2024-04-10 WENHUI SONG, YUNHU LU, YIHUA GAO, BOWEN YAO, YAN JIN, MIAN CHEN
The challenges of modeling shale oil transport are numerous and include strong solid-fluid interactions, fluid rheology, the multi-scale nature of the pore structure problem, and the different pore types involved. Until now, theoretical studies have not fully considered shale oil transport mechanisms and multi-scale pore structure properties. In this study, we propose a fractal-based oil transport
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Motion of test particles in quasi anti-de Sitter regular black holes Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-04-09 Dario Corona, Roberto Giambò, Orlando Luongo
In this paper, we explore the characteristics of two novel regular spacetimes that exhibit a nonzero vacuum energy term, under the form of a (quasi) anti-de Sitter phase. Specifically, the first metric is spherical, while the second, derived by applying the generalized Newman–Janis algorithm to the first, is axisymmetric. We show that the equations of state of the effective fluids associated with the
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NOVEL UNIFIED STABILITY CRITERION FOR FRACTIONAL-ORDER TIME DELAY SYSTEMS WITH STRONG RESISTANCE TO FRACTIONAL ORDERS Fractals (IF 4.7) Pub Date : 2024-04-09 ZHE ZHANG, CHENGHAO XU, YAONAN WANG, JIANQIAO LUO, XU XIAO
In this study, a novel unified stability criterion is first proposed for general fractional-order systems with time delay when the fractional order is from 0 to 1. Such a new unified criterion has the advantage of having an initiative link with the fractional orders. A further advantage is that the corresponding asymptotic stability theorem, derived from the proposed criterion used to analyze the asymptotic
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SOME RESULTS ON BOX DIMENSION ESTIMATION OF FRACTAL CONTINUOUS FUNCTIONS Fractals (IF 4.7) Pub Date : 2024-04-09 HUAI YANG, LULU REN, QIAN ZHENG
In this paper, we explore upper box dimension of continuous functions on [0,1] and their Riemann–Liouville fractional integral. Firstly, by comparing function limits, we prove that the upper box dimension of the Riemann–Liouville fractional order integral image of a continuous function will not exceed 2−υ, the result similar to [Y. S. Liang and W. Y. Su, Fractal dimensions of fractional integral of
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A STUDY OF THE THERMAL EVOLUTION OF PERMEABILITY AND POROSITY OF POROUS ROCKS BASED ON FRACTAL GEOMETRY THEORY Fractals (IF 4.7) Pub Date : 2024-04-09 TONGJUN MIAO, AIMIN CHEN, RICHENG LIU, PENG XU, BOMING YU
The temperature effect on the permeability of porous rocks continues to be a considerable controversy in the area of reservoirs since the thermal expansion of mineral grains exhibits complicated influence on pore geometries in them. To investigate the degree of effect of pore structures on the hydro-thermal coupling process, a study of the thermal evolution of permeability and porosity of porous rocks
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FRACTAL DIMENSIONS FOR THE MIXED (κ,s)-RIEMANN–LIOUVILLE FRACTIONAL INTEGRAL OF BIVARIATE FUNCTIONS Fractals (IF 4.7) Pub Date : 2024-04-09 B. Q. WANG, W. XIAO
The research object of this paper is the mixed (κ,s)-Riemann–Liouville fractional integral of bivariate functions on rectangular regions, which is a natural generalization of the fractional integral of univariate functions. This paper first indicates that the mixed integral still maintains the validity of the classical properties, such as boundedness, continuity and bounded variation. Furthermore,
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ANALYSIS OF THE EFFECT OF VARIOUS MENTAL TASKS ON THE EEG SIGNALS’ COMPLEXITY Fractals (IF 4.7) Pub Date : 2024-04-09 NAJMEH PAKNIYAT, ONDREJ KREJCAR, PETRA MARESOVA, JAMALUDDIN ABDULLAH, HAMIDREZA NAMAZI
Analysis of the brain activity in different mental tasks is an important area of research. We used complexity-based analysis to study the changes in brain activity in four mental tasks: relaxation, Stroop color-word, mirror image recognition, and arithmetic tasks. We used fractal theory, sample entropy, and approximate entropy to analyze the changes in electroencephalogram (EEG) signals between different
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Flux ruled surfaces and the magnetic curves obtained from the curvature theory Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-04-03 Çağla Gizem Şener, Fatma Güler
In this paper, our aim is to research the change in the magnetic field using the curvature theory of ruled surfaces. For this, we examine magnetic curves of the curve whose existence is guaranteed from the derivative formulas of the rotation frame. The Killing vector fields and Lorentz forces of these magnetic curves are calculated. Additionally, correlations between curvatures are obtained. Flux ruled
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Optical properties of a class of generalized conics Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-04-03 Eric Guiot
The optical and geometric properties of a class of generalized conics are presented. The study makes it possible to find in an original way several results of classical geometry and to connect numerous curves by a common law. Applications in geometric optics are envisaged, with the production of diopters, lenses or mirrors.
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CHAOS THEORY, ADVANCED METAHEURISTIC ALGORITHMS AND THEIR NEWFANGLED DEEP LEARNING ARCHITECTURE OPTIMIZATION APPLICATIONS: A REVIEW Fractals (IF 4.7) Pub Date : 2024-04-05 AKIF AKGUL, YELl̇Z KARACA, MUHAMMED ALI PALA, MURAT ERHAN ÇIMEN, ALI FUAT BOZ, MUSTAFA ZAHID YILDIZ
Metaheuristic techniques are capable of representing optimization frames with their specific theories as well as objective functions owing to their being adjustable and effective in various applications. Through the optimization of deep learning models, metaheuristic algorithms inspired by nature, imitating the behavior of living and non-living beings, have been used for about four decades to solve
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EXACT SOLUTIONS AND BIFURCATION OF A MODIFIED GENERALIZED MULTIDIMENSIONAL FRACTIONAL KADOMTSEV–PETVIASHVILI EQUATION Fractals (IF 4.7) Pub Date : 2024-04-05 MINYUAN LIU, HUI XU, ZENGGUI WANG, GUIYING CHEN
In this paper, we investigate the exact solutions of a modified generalized multidimensional fractional Kadomtsev–Petviashvili (KP) equation by the bifurcation method. First, the equation is converted into a planar dynamical system through fractional complex wave transformation. The phase portraits of the equation and qualitative analysis are presented under different bifurcation conditions. Then,
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SOME ZAGREB-TYPE INDICES OF VICSEK POLYGON GRAPHS Fractals (IF 4.7) Pub Date : 2024-04-05 ZHIQIANG WU, YUMEI XUE, HUIXIA HE, CHENG ZENG, WENJIE WANG
Chemical graph theory plays an essential role in modeling and designing any chemical structure or chemical network. For a (molecular) graph, the Zagreb indices and the Zagreb eccentricity indices are well-known topological indices to describe the structure of a molecule or graph and can be used to predict properties such as the size and number of rings in a molecule, as well as the thermodynamic stability
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VARIATIONAL FORMULATIONS FOR A COUPLED FRACTAL–FRACTIONAL KdV SYSTEM Fractals (IF 4.7) Pub Date : 2024-04-03 YINGZI GUAN, KHALED A. GEPREEL, JI-HUAN HE
Every shallow-water wave propagates along a fractal boundary, and its mathematical model cannot be precisely represented by integer dimensions. In this study, we investigate a coupled fractal–fractional KdV system moving along an irregular boundary within the framework of variational theory, which is commonly employed to derive governing equations. However, not every fractal–fractional differential
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A NEW ROUGH FRACTURE PERMEABILITY MODEL OF COAL WITH INJECTED WATER BASED ON DAMAGED TREE-LIKE BRANCHING NETWORK Fractals (IF 4.7) Pub Date : 2024-04-03 ZHEN LIU, ZHENG LI, HE YANG, JING HAN, MUYAO ZHU, SHUAI DONG, ZEHAN YU
The fracture network structure of coal is very complex, and it has always been a hot issue to characterize the fracture network structure of coal by using a tree-like branching network. In this paper, a new rough fracture permeability model of water injection coal based on a damaged tree-like branching network is proposed. In this model, fractal theory and sine wave model are used to characterize the
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DECODING OF THE EXTRAOCULAR MUSCLES ACTIVATIONS BY COMPLEXITY-BASED ANALYSIS OF ELECTROMYOGRAM (EMG) SIGNALS Fractals (IF 4.7) Pub Date : 2024-04-03 SRIDEVI SRIRAM, KARTHIKEYAN RAJAGOPAL, ONDREJ KREJCAR, HAMIDREZA NAMAZI
The analysis of extraocular muscles’ activation is crucial for understanding eye movement patterns, providing insights into oculomotor control, and contributing to advancements in fields such as vision research, neurology, and biomedical engineering. Ten subjects went through the experiments, including normal watching, blinking, upward and downward movements of eyes, and eye movements to the left and
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RESEARCH ON FRACTAL DIMENSIONS AND THE HÖLDER CONTINUITY OF FRACTAL FUNCTIONS UNDER OPERATIONS Fractals (IF 4.7) Pub Date : 2024-04-01 BINYAN YU, YONGSHUN LIANG
Based on the previous studies, we make further research on how fractal dimensions of graphs of fractal continuous functions under operations change and obtain a series of new results in this paper. Initially, it has been proven that a positive continuous function under unary operations of any nonzero real power and the logarithm taking any positive real number that is not equal to one as the base number
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INVESTIGATION ON CONCRETE MICROSTRUCTURAL EVOLUTION AND SLOPE STABILITY BASED ON COUPLED FRACTAL FLUID–STRUCTURE MODEL Fractals (IF 4.7) Pub Date : 2024-04-01 TINGTING YANG, YANG LIU, GUANNAN LIU, BOMING YU, MINGYAO WEI
Slope instability is a common type of damage in embankment dams. Analyzing its microstructural changes during water transport is beneficial to identify the critical damage point in more detail. To this end, we closely link both diffused water molecule and damaged concrete. On the basis of the original research on fractal theory, the fractal permeability model for the pore system is established. At
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Some characterizations of Quasi-Einstein and doubly product manifold Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-03-28 H. K. Elsayied, A. M. Tawfiq, A. Elsharkawy
This research paper explores the properties of quasi-Einstein manifolds with a unit concircular generator vector field within doubly warped product structures. The paper begins by investigating the characteristics of quasi-Einstein manifolds that possess a unit concircular generator vector field. Subsequently, it analyzes the behavior of the Hessian, Riemann, and Ricci vector fields in the context
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Quasi-static evolution of axially and reflection symmetric large-scale configuration Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-03-26 Z. Yousaf, Kazuharu Bamba, M. Z. Bhatti, U. Farwa
In this paper, we review a recently offered notion of quasi-static evolution of the axial self-gravitating structures at large scales and the criterium to characterize the corresponding evolutionary aspects under the influence of strong curvature regimes. In doing so, we examine the axial source’s dynamic and quasi-static behavior within the parameters of various modified gravity theories. We address
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A revisit to classical and quantum aspects of Raychaudhuri equation and possible resolution of singularity Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-03-26 Subenoy Chakraborty, Madhukrishna Chakraborty
In this review, we provide a concrete overview of the Raychaudhuri equation, Focusing Theorem and convergence conditions in a plethora of backgrounds and discuss the consequences. We also present various classical and quantum approaches suggested in the literature that could potentially mitigate the initial big-bang singularity and the black-hole singularity.
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FRACTAL ANALYSIS FOR PERMEABILITY OF MULTIPLE SHALE GAS TRANSPORT MECHANISMS IN ROUGHENED TREE-LIKE NETWORKS Fractals (IF 4.7) Pub Date : 2024-03-27 YIDAN ZHANG, BOQI XIAO, YANBIN WANG, GUOYING ZHANG, YI WANG, HAORAN HU, GONGBO LONG
In this work, a new gas transport model for shale reservoirs is constructed by embedding randomly distributed roughened tree-like bifurcation networks into the matrix porous medium. We constructed apparent permeability models for different shale gas flow mechanisms based on fractal theory, taking into account the effects of relative roughness and surface diffusion. The effects of bifurcation structure
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A NOVEL TRANSFORMER METHOD PRETRAINED WITH MASKED AUTOENCODERS AND FRACTAL DIMENSION FOR DIABETIC RETINOPATHY CLASSIFICATION Fractals (IF 4.7) Pub Date : 2024-03-27 YAOMING YANG, ZHAO ZHA, CHENNAN ZHOU, LIDA ZHANG, SHUXIA QIU, PENG XU
Diabetic retinopathy (DR) is one of the leading causes of blindness in a significant portion of the working population, and its damage on vision is irreversible. Therefore, rapid diagnosis on DR is crucial for saving the patient’s eyesight. Since Transformer shows superior performance in the field of computer vision compared with Convolutional Neural Networks (CNNs), it has been proposed and applied
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3D RENDERING OF THE QUATERNION MANDELBROT SET WITH MEMORY Fractals (IF 4.7) Pub Date : 2024-03-27 RICARDO FARIELLO, PAUL BOURKE, GABRIEL V. S. ABREU
In this paper, we explore the quaternion equivalent of the Mandelbrot set equipped with memory and apply various visualization techniques to the resulting 4-dimensional geometry. Three memory functions have been considered, two that apply a weighted sum to only the previous two terms and one that performs a weighted sum of all previous terms of the series. The visualization includes one or two cutting
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SOME NEW PARAMETRIZED INEQUALITIES ON FRACTAL SET Fractals (IF 4.7) Pub Date : 2024-03-27 HONGYAN XU, ABDELGHANI LAKHDARI, WEDAD SALEH, BADREDDINE MEFTAH
The aim of this study is to examine certain open three-point Newton–Cotes-type inequalities for differentiable generalized s-convex functions on a fractal set. To begin, we introduce a novel parametrized identity involving the relevant formula, which yields various new findings as well as previously established ones. Finally, an example is given to demonstrate the accuracy of the new results and their
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THE (IN)EFFICIENCY OF USA EDUCATION GROUP STOCKS: BEFORE, DURING AND AFTER COVID-19 Fractals (IF 4.7) Pub Date : 2024-03-26 LEONARDO H. S. FERNANDES, JOSÉ P. V. FERNANDES, JOSÉ W. L. SILVA, RANILSON O. A. PAIVA, IBSEN M. B. S. PINTO, FERNANDO H. A. DE ARAÚJO
This paper represents a pioneering effort to investigate multifractal dynamics that exclusively encompass the return time series of USA Education Group Stocks concerning two non-overlapping periods (before, during, and after COVID-19). Given this, we employ the Multifractal Detrended Fluctuations Analysis (MF-DFA). In this sense, we investigate the generalized Hurst exponent h(q) and the Rényi exponent
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SHORTEST PATH DISTANCE AND HAUSDORFF DIMENSION OF SIERPINSKI NETWORKS Fractals (IF 4.7) Pub Date : 2024-03-26 JIAQI FAN, JIAJUN XU, LIFENG XI
In this paper, we will study the geometric structure on the Sierpinski networks which are skeleton networks of a connected self-similar Sierpinski carpet. Under some suitable condition, we figure out that the renormalized shortest path distance is comparable to the planar Manhattan distance, and obtain the Hausdorff dimension of Sierpinski networks.
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APPLICATION OF FRACTIONAL-ORDER INTEGRAL TRANSFORMS IN THE DIAGNOSIS OF ELECTRICAL SYSTEM CONDITIONS Fractals (IF 4.7) Pub Date : 2024-03-26 H. M. CORTÉS CAMPOS, J. F. GÓMEZ-AGUILAR, C. J. ZÚÑIGA-AGUILAR, L. F. AVALOS-RUIZ, J. E. LAVÍN-DELGADO
This paper proposes a methodology for the diagnosis of electrical system conditions using fractional-order integral transforms for feature extraction. This work proposes three feature extraction algorithms using the Fractional Fourier Transform (FRFT), the Fourier Transform combined with the Mittag-Leffler function, and the Wavelet Transform (WT). Each algorithm extracts data from an electrical system
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COMPLEX NETWORKS GENERATED BY A SELF-SIMILAR PLANAR FRACTAL Fractals (IF 4.7) Pub Date : 2024-03-26 QIN WANG, WENJIA MA, KEQIN CUI, QINGCHENG ZENG, LIFENG XI
Many complex networks have scale-free and small-world effects. In this paper, a family of evolving networks is constructed modeled by a non-symmetric self-similar planar fractal, using the encoding method in fractal geometry. Based on the self-similar structure, we study the degree distribution, clustering coefficient and average path length of our evolving network to verify their scale-free and small-world
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Geometric phase for two-mode entangled squeezed-coherent states Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-03-25 S. Mohammadi Almas, G. Najarbashi, A. Tavana
In this paper, we investigate the geometric phase (GP) of two-mode entangled squeezed-coherent states (ESCSs), undergoing unitary cyclic evolution. Results show that increasing the squeezing parameter of either mode of the balanced ESCS compresses the GP elliptically with respect to the coherence parameter of the corresponding mode. While in the case of unbalanced ESCS, the GP is compressed hyperbolically
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Ricci solitons and curvature inheritance on Robinson–Trautman spacetimes Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-03-22 Absos Ali Shaikh, Biswa Ranjan Datta
The purpose of this paper is to investigate the existence of Ricci solitons and the nature of curvature inheritance as well as collineations on the Robinson–Trautman (briefly, RT) spacetime. It is shown that under certain conditions RT spacetime admits almost-Ricci soliton, almost-η-Ricci soliton, almost-gradient η-Ricci soliton. As a generalization of curvature inheritance [K. L. Duggal, Curvature
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Generalized variational structures of the (3 + 1)-dimensional Zakharov–Kuznetsov–Burgers equation in dusty plasma Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-03-22 Kang-Jia Wang, Shuai Li, Feng Shi
The center of this paper is to establish the generalized variational structure (GVS) of the (3+1)-dimensional Zakharov–Kuznetsov–Burgers equation (ZKBe) by taking advantage of the Semi-inverse method (SIM). Two different GVSs are extracted and the derivation process is presented in detail. The extracted GVSs reveal the energy conservation law and can offer some new insights on the study of the variational
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Energy density inhomogeneities with self-gravitating charged fluid in modified teleparallel gravity Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-03-22 M. Z. Bhatti, Nasser Bin Turki, S. Hanif, A. Malik
In this paper, we analyze energy density inhomogeneities for charged fluid configuration in the background of f(T) theory and recognize its prime features as computed in GR. The dynamical equations are composed employing Bianchi identities for the standard, f(T) extra terms, and energy-momentum tensor for the electromagnetic field. We evaluate various mathematical models of dissipative and anisotropic
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Some inequalities for bi-slant Riemannian submersions in complex space forms Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-03-21 Nergiz Poyraz, Yılmaz Gündüzalp, Mehmet Akif Akyol
The goal of this paper is to analyze sharp-type inequalities including the scalar and Ricci curvatures of bi-slant Riemannian submersions in complex space forms. Then, for bi-slant Riemannian submersion between a complex space form and a Riemannian manifold, we give inequalities involving the Casorati curvature of the space ker φ∗. Also, we mention some examples.
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A flat FLRW dark energy model in f(Q,C)-gravity theory with observational constraints Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-03-21 Anirudh Pradhan, Archana Dixit, M. Zeyauddin, S. Krishnannair
In the recently suggested modified non-metricity gravity theory with boundary term in a flat FLRW spacetime universe, dark energy scenarios of cosmological models are examined in this study. An arbitrary function, f(Q,C)=Q+αC2, has been taken into consideration, where Q is the non-metricity scalar, C is the boundary term denoted by C=R̈−Q, and α is the model parameter, for the action that is quadratic
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Bouncing universe scenario in f(Q,T) gravity model Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-03-21 S. Davood Sadatian, S. Mohamad Reza Hosseini
In this paper, we investigate the bouncing universe in a modified gravity model f(Q,T). The bouncing universe theory posits that the universe goes through periodic expansions and contractions, with a “bounce” occurring at the end of each contraction that leads to a new expansion. This theory suggests that our universe didn’t emerge on its own out of nothing, but is instead the latest in a series of
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The Kastler–Kalau–Walze-type theorems about J-Witten deformation Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-03-21 Siyao Liu, Yong Wang
In this paper, we obtain a Lichnerowicz-type formula for J-Witten deformation and give the proof of the Kastler–Kalau–Walze-type theorems associated with J-Witten deformation on four-dimensional and six-dimensional almost product Riemannian manifold with (respectively, without) boundary. We give an explanation of the Einstein–Hilbert action for J-Witten deformation on four-dimensional manifold with
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ON MULTIPLICATIVE (s,P)-CONVEXITY AND RELATED FRACTIONAL INEQUALITIES WITHIN MULTIPLICATIVE CALCULUS Fractals (IF 4.7) Pub Date : 2024-03-22 YU PENG, TINGSONG DU
In this paper, we propose a fresh conception about convexity, known as the multiplicative (s,P)-convexity. Along with this direction, we research the properties of such type of convexity. In the framework of multiplicative fractional Riemann–Liouville integrals and under the ∗differentiable (s,P)-convexity, we investigate the multiplicative fractional inequalities, including the Hermite–Hadamard- and
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Spectrum and q-index of the super q-deformed Dirac operator on the superquantum fuzzy two-sphere Sqμ(2|2) Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-03-16 M. Mahmoodi, M. Lotfizadeh, Behnam Mohammadi
In this paper, we have computed the spectrum and the q-index of the super q-deformed Ginsparg–Wilson Dirac operator in the different cases (fuzzy, non-fuzzy, gauged, and non-gauged) on the superquantum fuzzy two-sphere Sqμ(2|2). We also presented the appropriate spin structure that this operator acts on the superquantum (Dirac) spinor bundle. Finally, it was shown that in the non-quantum limit, when
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Behaviors of black holes and black strings in M-theory on Calabi–Yau manifolds Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-03-16 Adil Belhaj, Abderrahim Bouhouch
In this work, we reconsider the study of black holes and black strings in the compactification of M-theory on a Calabi–Yau three-fold, considered as a complete intersection of hypersurfaces in a product of weighted projective spaces given by 𝕎ℙ4(ω,1,1,1,1)×ℙ1. Using the N=2 supergravity formalism in five dimensions, we examine the BPS and non-BPS solutions by wrapping M-branes on appropriate cycles
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Introduction to loop quantum gravity. The Holst’s action and the covariant formalism Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-03-13 L. Fatibene, A. Orizzonte, A. Albano, S. Coriasco, M. Ferraris, S. Garruto, N. Morandi
We review Holst formalism and dynamical equivalence with standard GR (in dimension 4). Holst formalism is written for a spin coframe field eμI and a Spin(3,1)-connection ωμIJ on spacetime M and it depends on the Holst parameterγ∈ℝ−{0}. We show the model is dynamically equivalent to standard GR, in the sense that up to a pointwise Spin(3,1)-gauge transformation acting on (uppercase Latin) frame indices
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First-order quantum correction of thermodynamics in a charged accelerating AdS black hole with gauge potential Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2024-03-13 Riasat Ali, Rimsha Babar, Houcine Aounallah, Ali Övgün
In this paper, we study the tunneling radiation from a charged-accelerating AdS black hole with gauge potential under the impact of quantum gravity. Using the semi-classical phenomenon known as the Hamilton–Jacobi ansatz, it is studied that tunneling radiation occurs via the horizon of a black hole and also employs the Lagrangian equation using the generalized uncertainty principle. Furthermore, we