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Thin-shell wormholes with electromagnetic effects in f(R,T) gravity Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-08-24 M. Z. Bhatti, Z. Yousaf, M. Nazeer
The purpose of this paper is to study the feasibility and the appearance of charged thin-shell wormholes using generalized Chaplygin gas under the influence of minimally coupled f(R,T) gravitational theory. Here, f is a generic function of the scalar curvature R and the trace of stress-energy tensor T. We explore different components of Lanczos equations in the context of a specific f(R,T) functional
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(m,ρ)-quasi-Einstein solitons on 3-dimensional trans-Sasakian manifolds and its applications in spacetimes Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-08-24 Avijit Sarkar, Urmila Biswas
This paper characterizes (m,ρ)-quasi-Einstein solitons on 3-dimensional trans-Sasakian manifolds. It has been shown that a closed (m,ρ)-quasi-Einstein soliton on a 3-dimensional trans-Sasakian manifold is either cosymplectic or Einstein under certain restrictions. Moreover, we investigate (m,ρ)-quasi-Einstein solitons with certain potential vector fields on 3-dimensional trans-Sasakian manifolds. As
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Energy constraints for static wormholes in f(ℛ,𝒯 ) gravity Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-08-22 G. Abbas, S. Taj, Aisha Siddida, Zohra Arbab
The tunnel-like structures proposed by Morris and Thorne are explored in this study by using f(ℛ,𝒯) framework. The solutions of static wormhole, supported by the matter possess van der Waals equation of state, are derived by two possible schemes. We have explored the shape function and energy conditions including null, weak, strong and dominant conditions. For this purpose, we used the equation of
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A NEW FRACTAL MODEL FOR PREDICTING SATURATED SOIL PERMEABILITY UNDER DIFFERENT DEFORMATION Fractals (IF 4.7) Pub Date : 2023-08-23 GAOLIANG TAO, FAN ZHANG, WEI ZHAO, HENGLIN XIAO, QINGSHENG CHEN, SUDIP BASACK, LISHENG LIU
The permeability coefficient and air-entry value of saturated soil are important hydraulic properties, which play an important role in engineering applications. Subsoil supporting foundation is subjected to stress and undergoes deformation; the saturated permeability coefficient of such deformed soil is of practical importance. With the help of fractal theory, based on the different fractal forms of
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THE PORE SIZE-DEPENDENT FRACTALITY OF POROUS STRUCTURE IN CEMENT PASTE: ANALYSIS, MODELING AND APPLICATIONS Fractals (IF 4.7) Pub Date : 2023-08-23 YANAN XI, WENWEI LI, DONG LEI, YUN GAO
The fractal characteristic of cement paste has been investigated for decades. In this paper, a systematic study referring to analysis, modeling as well as application is presented with respect to the pore size-dependent fractality of the porous structure in cement paste. In particular, the multiscale fractal dimensions other than the traditional single fractal dimension are analyzed for a measure of
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A NOVEL ANALYTICAL MODEL OF THE EFFECTIVE THERMAL CONDUCTIVITY OF POROUS MATERIALS UNDER STRESS Fractals (IF 4.7) Pub Date : 2023-08-23 JIADI TANG, GANG LEI, XIAODONG LI, LING ZHANG, WAN CHENG, JIANGTAO PANG, GUOSHENG JIANG
With the increasing demand for energy, heat and mass transfer through porous media has been widely studied. To achieve accuracy in studying the behavior of heat transfer, a good knowledge of the effective thermal conductivity (ETC) of porous materials is needed. Because pore structure dominates the ETC of porous materials and effective stress leads to a change in pore structure, effective stress is
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A METHOD FOR PREDICTING UNSATURATED SOIL PERMEABILITY COEFFICIENT BASED ON CLAY CONTENT Fractals (IF 4.7) Pub Date : 2023-08-23 GAOLIANG TAO, YINJIE PENG, YIMING LIU
The unsaturated permeability coefficient is of importance to study the behavior of the water seepage and contaminant transport in unsaturated soils. The direct measurement of the unsaturated permeability coefficient is time consuming and laborious. Therefore, indirect approaches are usually applied to obtain the unsaturated permeability coefficient. However, indirect methods still have some drawbacks
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A NUMERICAL STUDY OF COMPLEX DYNAMICS OF A CHEMOSTAT MODEL UNDER FRACTAL-FRACTIONAL DERIVATIVE Fractals (IF 4.7) Pub Date : 2023-08-23 ZAREEN A. KHAN, KAMAL SHAH, BAHAAELDIN ABDALLA, THABET ABDELJAWAD
In this paper, we study the existence of numerical solution and stability of a chemostat model under fractal-fractional order derivative. First, we investigate the positivity and roundedness of the solution of the considered system. Second, we find the existence of a solution of the considered system by employing the Banach and Schauder fixed-point theorems. Furthermore, we obtain a sufficient condition
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THEORETICAL AND NUMERICAL COMPUTATIONS OF CONVEXITY ANALYSIS FOR FRACTIONAL DIFFERENCES USING LOWER BOUNDEDNESS Fractals (IF 4.7) Pub Date : 2023-08-23 PSHTIWAN OTHMAN MOHAMMED, DUMITRU BALEANU, EMAN AL-SARAIRAH, THABET ABDELJAWAD, NEJMEDDINE CHORFI
This study focuses on the analytical and numerical solutions of the convexity analysis for fractional differences with exponential and Mittag-Leffler kernels involving negative and nonnegative lower bounds. In the analytical part of the paper, we will give a new formula for ∇2 of the discrete fractional differences, which can be useful to obtain the convexity results. The correlation between the nonnegativity
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EXPERIMENTAL INVESTIGATION ON FRACTAL CHARACTERIZATION OF IN-SITU FOAM IN POROUS MEDIA Fractals (IF 4.7) Pub Date : 2023-08-23 HAILONG CHEN, BINGXIN JI, FEI WANG, YUCHEN WANG, FAMING ZENG, ZHAOMIN LI, QI JIANG
The in-situ foam technology has been extensively applied in the complex reservoir reconstruction since it improves the sweep efficiency by diverting the flow of injected fluids into areas with lower permeability and as a result enhances the oil recovery. The in-situ foam structure inside the pores can significantly affect the sweep efficiency, however, quantitative characterizations on foam structure
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VARIATIONAL PRINCIPLES FOR FRACTAL BOUSSINESQ-LIKE B(m,n) EQUATION Fractals (IF 4.7) Pub Date : 2023-08-23 YAN WANG, KHALED A. GEPREEL, YONG-JU YANG
The variational theory has triggered skyrocketing interest in the solitary theory, and the semi-inverse method has laid the foundation for the search for a variational formulation for a nonlinear system. This paper gives a brief review of the last development of the fractal soliton theory and discusses the variational principle for fractal Boussinesq-like B(m,n) equation in the literature. The paper
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Characterizations of quasi-Einstein spacetimes and f(ℛ,G)-gravity Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-08-22 Uday Chand De, Dipankar Hazra, Fatemah Mofarreh
First, we illustrate that a Ricci symmetric quasi-Einstein spacetime is a static spacetime and belongs to Petrov classification I, D or O. We investigate conformally flat quasi-Einstein spacetime as a solution of f(ℛ,G)-gravity theory and explain the physical meaning of the Friedmann–Robertson–Walker metric. For the models f(ℛ,G)=μℛβ1Gβ2, (β1, β2 and μ are constants) and f(ℛ,G)=ℛ2−6G, various energy
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ADAMS–BASHFORTH NUMERICAL METHOD-BASED SOLUTION OF FRACTIONAL ORDER FINANCIAL CHAOTIC MODEL Fractals (IF 4.7) Pub Date : 2023-08-22 RAJARAMA MOHAN JENA, SNEHASHISH CHAKRAVERTY, SHENGDA ZENG, VAN THIEN NGUYEN
A new definition of fractional differentiation of nonlocal and non-singular kernels has recently been developed to overcome the shortcomings of the traditional Riemann–Liouville and Caputo fractional derivatives. In this study, the dynamic behaviors of the fractional financial chaotic model have been investigated. Singular and non-singular kernel fractional derivatives are used to examine the proposed
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TESTING FOR INTRINSIC MULTIFRACTALITY IN THE GLOBAL GRAIN SPOT MARKET INDICES: A MULTIFRACTAL DETRENDED FLUCTUATION ANALYSIS Fractals (IF 4.7) Pub Date : 2023-08-22 LI WANG, XING-LU GAO, WEI-XING ZHOU
Grains account for more than 50% of the calories consumed by people worldwide, and military conflicts, pandemics, climate change, and soaring grain prices all have vital impacts on food security. However, the complex price behavior of the global grain spot markets has not been well understood. A recent study performed multifractal moving average analysis (MF-DMA) of the Grains & Oilseeds Index (GOI)
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THE WEIGHTED PARAMETERIZED INEQUALITIES IN RELATION TO TWICE DIFFERENTIABLE MAPPINGS IN THE FRACTAL DOMAINS ALONG WITH SOME APPLICATIONS Fractals (IF 4.7) Pub Date : 2023-08-22 YUNXIU ZHOU, JIAGEN LIAO, TINGSONG DU
In this paper, two weighted parameterized fractal identities are first proposed, wherein the mappings involved are second-order local fractional differentiable. Based upon these equalities, a series of the weighted parameterized inequalities, which are related to the fractal convex mappings, are then deduced. Moreover, making use of boundedness and (φ,ρ𝜗̂)-Lipschitzian mappings, some error estimates
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GAS PERMEABILITY IN POROUS MEDIA WITH ROUGH SURFACES BY FRACTAL-MONTE CARLO SIMULATIONS Fractals (IF 4.7) Pub Date : 2023-08-18 ZUOZHUANG YIN, SILIANG DUAN, XIUYA GUO, HUILI WANG, RUIJUAN CHEN, QIAN ZHENG
Gas permeability is an important parameter for gas transport in microporous and nanoporous media. A probability model of gas permeability of fractal porous media with rough surfaces is proposed and numerically simulated by the Monte Carlo technique. This model consists of two gas flow mechanisms: the Poiseuille flow and the Knudsen flow, and can be expressed by structural parameters, such as the pore
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A NEW SEVEN-REGION FLOW MODEL FOR DELIVERABILITY EVALUATION OF MULTIPLY-FRACTURED HORIZONTAL WELLS IN TIGHT OIL FRACTAL RESERVOIR Fractals (IF 4.7) Pub Date : 2023-08-18 FANRONG GUO, ROU CHEN, WEIWEI YAN, YING SU, YANYAN HU, SHENGCHUN XIONG
Deliverability evaluation plays an important role in the reservoir exploitation. In this study, a new seven-region semi-analytical mathematical model considering the influences of fractal, imbibition and non-Darcy flow is proposed to evaluate the deliverability of multiply-fractured horizontal wells in tight oil reservoirs. The Laplace transformation, perturbation method and Stehfest numerical inversion
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NON-INVASIVE DIAGNOSIS OF LUNG CANCER BASED ON CFD MODELING AND FRACTAL ANALYSIS Fractals (IF 4.7) Pub Date : 2023-08-18 ROU CHEN, YING ZHOU, WEIWEI YAN, HUA LI
Due to a great majority of lung cancer patients dying within one year after being diagnosed with apparent symptoms, developing a diagnostic/monitoring technique for early-stage lung cancer is in critical demand. Conventionally, lung cancer diagnostic approaches are costly, and they increase the health risks caused by invasiveness and radiation hazards. In this work, a new diagnostic technique using
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A NOVEL KOZENY–CARMAN CONSTANT MODEL FOR POROUS MEDIA EMBEDDED WITH TREE-LIKE BRANCHING NETWORKS WITH ROUGHENED SURFACES Fractals (IF 4.7) Pub Date : 2023-08-18 BOQI XIAO, FENGYE CHEN, YIDAN ZHANG, SHAOFU LI, GUOYING ZHANG, GONGBO LONG, HUAN ZHOU, YI LI
Although the hydraulic features of the tree-like branching network have been widely investigated, the seepage characteristics of the networks have not been studied sufficiently. In this study, the seepage characteristics of porous media embedded with a tree-like branching network with the effects of roughness are studied based on fractal theory. Then, the Kozeny–Carman (KC) constant of the composite
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INVESTIGATION OF THE FRACTIONAL KdV–ZAKHAROV–KUZNETSOV EQUATION ARISING IN PLASMA PHYSICS Fractals (IF 4.7) Pub Date : 2023-08-18 KANG-LE WANG
The KdV–Zakharov–Kuznetsov equation is an important and interesting mathematical model in plasma physics, which is used to describe the effect of magnetic field on weak nonlinear ion-acoustic waves. A fractional KdV–Zakharov–Kuznetsov equation in the M-truncated derivative sense is investigated. By taking into account the fractional tanhδ method and fractional sineδ–cosineδ method, larger numbers of
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A HYBRID FRACTIONAL-DERIVATIVE AND PERIDYNAMIC MODEL FOR WATER TRANSPORT IN UNSATURATED POROUS MEDIA Fractals (IF 4.7) Pub Date : 2023-08-18 YUANYUAN WANG, HONGGUANG SUN, TAO NI, MIRCO ZACCARIOTTO, UGO GALVANETTO
Richards’ equation is a classical differential equation describing water transport in unsaturated porous media, in which the moisture content and the soil matrix depend on the spatial derivative of hydraulic conductivity and hydraulic potential. This paper proposes a nonlocal model and the peridynamic formulation replace the temporal and spatial derivative terms. Peridynamic formulation utilizes a
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A NEW RANDOM REWIRING METHOD TO TRANSFORM FRACTAL NETWORKS INTO SMALL-WORLD NETWORKS Fractals (IF 4.7) Pub Date : 2023-08-18 JIAN-HUI LI, ZU-GUO YU, VO V. ANH, JIN-LONG LIU, AN-QI PENG
The fractal and small-word properties are two important properties of complex networks. In this paper, we propose a new random rewiring method to transform fractal networks into small-world networks. We theoretically prove that the proposed method can retain the degree of all nodes (hence the degree distribution) and the connectivity of the network. Further, we also theoretically prove that our method
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NOVEL APPROACHES TO FRACTIONAL KLEIN–GORDON–ZAKHAROV EQUATION Fractals (IF 4.7) Pub Date : 2023-08-18 KANG LE WANG
The Klein–Gordon–Zakharov equation is an important and interesting model in physics. A fractional Klein–Gordon–Zakharov model is described by employing beta-derivative. Some new solitary wave solutions are acquired by utilizing the fractional rational sinhσ–coshσ method and fractional sechσ method. Some 3D graphs are depicted to elaborate these new solitary wave solutions. The work is very helpful
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Symmetries in Cartan’s formalism: A review with examples Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-08-17 Yuri Bonder, Cristóbal Corral, Oscar Ramírez
We review an algorithm, in the context of gauge and gravity theories described by differential forms, to read off the symmetries of a physical system out of its action, which was originally proposed in [C. Corral and Y. Bonder, Symmetry algebra in gauge theories of gravity, Class. Quantum Grav.36 (2019) 045002]. In particular, we study the interplay between gauge symmetries and a gauge-covariant version
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Thermodynamics of massless particles in curved spacetime Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-08-12 A. A. Araújo Filho
This work is devoted to study the behavior of massless particles within the context of curved spacetime. In essence, we investigate the consequences of the scale factor C(η) of the Friedmann–Robertson–Walker metric in the Einstein–aether formalism to study photon-like particles. To do so, we consider the system within the canonical ensemble formalism in order to derive the following thermodynamic state
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Scalar fields described by Dirac quaternion wave equation Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-08-11 Victor L. Mironov, Sergey V. Mironov
In this paper, we discuss the fields described by Dirac wave equation written in Clifford algebra based on Macfalane quaternions. It is shown that the strengths of these fields are nonzero only in the area of sources and the interaction of such fields occurs by overlapping. We consider both the simple spherically symmetric models of sources, which demonstrate attractive and repulsive interaction, and
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Optical solitons of a cubic-quartic nonlinear Schrödinger equation with parabolic law nonlinearity in optical metamaterials Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-08-11 Sebahat Ebru Das, Muslum Ozisik, Mustafa Bayram, Aydin Secer, Pinar Albayrak
This paper aims to reveal the effects of the fourth-order dispersion and parabolic law which comes from self-phase modulation on the soliton behavior of the cubic-quartic nonlinear Schrödinger equation (CQ-NLSE) by using the modified new Kudryashov method. First, applying the complex wave transformation, the nonlinear ordinary differential form (NODE) has been obtained. Then, the modified new Kudryashov
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Holographic description of F(R) gravity coupled with axion dark matter Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-08-08 Simone D’Onofrio
In this work, we study the autonomous dynamical system of different F(R) models in the formalism of holographic dark energy using the generalized Nojiri–Odintsov cut-off. We explicitly give the expression of the fixed points as functions of the infrared cut-off for vacuum F(R) gravity in flat and non-flat FRW background and for F(R) coupling axion dark matter. Each fixed point component can be taken
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Compact relativistic sphere with charged anisotropic matter in f(R,G) gravity Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-08-08 M. Ilyas, Rohna Iqbal
The main purpose of this research is to examine a number of interior configurations of stable anisotropic objects formed in the shape of spherical charged stars within the gravity region described by f(R,G), where G represents the Gauss–Bonnet invariant and R defines the Ricci Scalar in this scenario. The formation of these charged stars is investigated using the solutions found by Karori and Barua
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TRAPPING PROBLEM OF HONEYPOTS ON FRACTAL NETWORKS WITH THE STURMIAN STRUCTURE Fractals (IF 4.7) Pub Date : 2023-08-10 YUKE HUANG, CHENG ZENG, YUMEI XUE
This paper studies the average trapping time of honeypots on some evolving networks. We propose a simple algorithmic framework for generating networks with Sturmian structure. From the balance property and the recurrence property of Sturmian words, we estimate the average trapping time of our proposed networks with an asymptotic expression 〈T〉t∼Mt(α)2t, where Mt(α) is a bounded expression related to
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STOCHASTIC STABILITY AND PARAMETRIC CONTROL IN A GENERALIZED AND TRI-STABLE VAN DER POL SYSTEM WITH FRACTIONAL ELEMENT DRIVEN BY MULTIPLICATIVE NOISE Fractals (IF 4.7) Pub Date : 2023-08-10 YA-JIE LI, ZHI-QIANG WU, YONG-TAO SUN, YING HAO, XIANG-YUN ZHANG, FENG WANG, HE-PING SHI
The stochastic transition behavior of tri-stable states in a fractional-order generalized Van der Pol (VDP) system under multiplicative Gaussian white noise (GWN) excitation is investigated. First, according to the minimal mean square error (MMSE) concept, the fractional derivative can be equivalent to a linear combination of damping and restoring forces, and the original system can be simplified into
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THE PARAMETERIZED INTEGRAL INEQUALITIES INVOLVING TWICE-DIFFERENTIABLE GENERALIZED n-POLYNOMIAL CONVEXITY UNDER THE FRAMEWORK OF FRACTAL DOMAINS AND ITS APPLICATIONS Fractals (IF 4.7) Pub Date : 2023-08-09 TINGSONG DU, LEI XU, XIAOMAN YUAN
A fractal integral identity with the parameter τ related to twice-differentiable mappings is first proposed in this paper. Based on the identity, the parameterized inequalities over the fractal domains are then derived for the mappings whose second-order derivatives in absolute value at certain powers are generalized n-polynomial convex, which is the main purpose of this investigation. Moreover, a
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A FRACTAL ELECTRICAL CONDUCTIVITY MODEL FOR WATER-SATURATED TREE-LIKE BRANCHING NETWORK Fractals (IF 4.7) Pub Date : 2023-08-09 HUAIZHI ZHU, BOQI XIAO, YIDAN ZHANG, HUAN ZHOU, SHAOFU LI, YANBIN WANG, GONGBO LONG
Electrical conductivity is an important physical property of porous media, and has great significance to rock physics and reservoir engineering. In this work, a conductivity model including pore water conductivity and surface conductivity is derived for water-saturated tree-like branching network. In addition, combined with Archie’s law, a general analytical formula for the formation factor is presented
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NONLOCAL LOW RANK REGULARIZATION METHOD FOR FRACTAL IMAGE CODING UNDER SALT-AND-PEPPER NOISE Fractals (IF 4.7) Pub Date : 2023-08-09 HUAN PAN, ZHENGYU LIANG, JIAN LU, KAI TU, NING XIE
Image denoising has been a fundamental problem in the field of image processing. In this paper, we tackle removing impulse noise by combining the fractal image coding and the nonlocal self-similarity priors to recover image. The model undergoes a two-stage process. In the first phase, the identification and labeling of pixels likely to be corrupted by salt-and-pepper noise are carried out. In the second
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POWER LAW DISTRIBUTION BASED ON MAXIMUM ENTROPY OF RANDOM PERMUTATION SET Fractals (IF 4.7) Pub Date : 2023-08-09 ZIHAN YU, ZHEN LI, YONG Deng
Among all probability distributions, power law distribution is an intriguing one, which has been studied by many researchers. However, the derivation of power law distribution is still an inconclusive topic. For deriving a distribution, there are various methods, among which maximum entropy principle is a special one. Entropy of random permutation set (RPS), as an uncertainty measure of RPS, is a newly
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GENERALIZED VARIATIONAL STRUCTURE OF THE FRACTAL MODIFIED KDV–ZAKHAROV–KUZNETSOV EQUATION Fractals (IF 4.7) Pub Date : 2023-08-09 KANG-JIA WANG, PENG XU
A fractal modification of the modified KdV–Zakharov–Kuznetsov equation is suggested and its fractal generalized variational structure is established by means of the semi-inverse method. Furthermore, the obtained fractal generalized variational structure is discussed and verified through the two-scale transform from another dimension field in detail. The obtained fractal generalized variational structure
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BIFURCATION AND EXACT SOLUTIONS OF SPACE-TIME FRACTIONAL SIMPLIFIED MODIFIED CAMASSA–HOLM EQUATION Fractals (IF 4.7) Pub Date : 2023-08-08 YANZHI MA, ZENGGUI WANG
In this paper, exact traveling wave solutions of space-time fractional simplified modified Camassa–Holm (mCH) equation are investigated by the bifurcation theory. The phase portraits of the equation are obtained with different parameter conditions. By analyzing different orbits, periodic wave, kink, anti-kink, burst wave, bright and dark solitary solutions of the equation are acquired. Finally, numerical
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HARDWARE ACCELERATION OF DNA READ ALIGNMENT PROGRAMS: CHALLENGES AND OPPORTUNITIES Fractals (IF 4.7) Pub Date : 2023-08-08 PACHECO-BAUTISTA DANIEL, CARREÑO-AGUILERA RICARDO, ALGREDO-BADILLO IGNACIO, PATIÑO-ORTIZ MIGUEL
The alignment or mapping of Deoxyribonucleic Acid (DNA) reads produced by the new massively parallel sequencing machines is a fundamental initial step in the DNA analysis process. DNA alignment consists of ordering millions of short nucleotide sequences called reads, using a previously sequenced genome as a reference, to reconstruct the genetic code of a species. Even with the efforts made in the development
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YANG TRANSFORM FOR THE HOMOTOPY PERTURBATION METHOD: PROMISE FOR FRACTAL-FRACTIONAL MODELS Fractals (IF 4.7) Pub Date : 2023-08-04 MUHAMMAD NADEEM, ZITIAN LI
This study presents the modified form of the homotopy perturbation method (HPM), and the Yang transform is adopted to simplify the solving process for the Kuramoto–Sivashinsky (KS) problem with fractal derivatives. This scheme is established by combining the two-scale fractal scheme and Yang transform, which is very helpful to evaluate the approximate solution of the fractal KS problem. Initially,
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NONLINEAR VIBRATION WITH DISCONTINUITIES IN A FRACTAL SPACE: ITS VARIATIONAL FORMULATION AND PERIODIC PROPERTY Fractals (IF 4.7) Pub Date : 2023-08-03 YUE SHEN, CHUN-HUI HE, ABDULRAHMAN ALI ALSOLAMI, DAN TIAN
A vibration system with discontinuities has triggered off rocketing interest in various fields including mechanical engineering, physics, and mathematics because it has many striking and amazing properties which cannot be unexplained by traditional vibration theory. This paper studies the problem using the energy conservation frame in a fractal time. A variational formulation is developed, and its
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Yukawa–Casimir wormhole model in F(R,T) framework Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-08-02 Shweta, Umesh Kumar Sharma, Ambuj Kumar Mishra
There is an unavoidable association of traversability of wormholes to the violation of null energy condition which in turn indicates the presence of exotic or non-exotic matter in the wormhole geometry. The exotic matter possesses the negative energy that is required to sustain the wormhole. Recently studies are done to solve this problem so as to avoid the exotic matter. In this work, we attempt to
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Deriving the generalized momentum operators from covariant derivatives Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-08-02 Mehdi Jafari Matehkolaee
The generalized momentum operators are derived in the framework of non-relativistic quantum mechanics, taking into account an especial assumption on the covariant derivative. According to this assumption, a scalar density doesn’t change under the action of covariant derivative. The Hermitian form of the covariant derivative is discussed. It is shown that, with the help of the adjoint of covariant derivatives
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Observational constraints on a transit cosmological model in f(R,G) gravity Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-08-01 Bhupendra Kumar Shukla, R. K. Tiwari, D. Sofuoğlu
In this article, we examine the universe’s dynamical behaviour in the context of the f(R,G) theory of gravity, where R and G represent the Ricci scalar and Gauss-Bonnet invariant, respectively. The modified field equations are solved for the selection of f(R,G) function as f(R,G)=RβG1−β and of the deceleration parameter as a linear function of Hubble parameter, i.e., q=n+mH. We predict the best fit
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Inflation and cosmological evolution with F(R,𝒢) gravity theory Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-08-01 Dalia Saha, Jyoti Prasad Saha, Abhik Kumar Sanyal
In the last decade Planck PR4 data together with ground-based experimental data such as BK18, BAO and CMB lensing tightened constraint of the tensor-to-scalar ratio, starting form r<0.14 to r<0.032, while the spectral index lies within the range 0.9631≤ns≤0.9705. Viability of modified gravity theories, proposed as alternatives to the dark energy issue, should therefore be tested in the light of such
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AN ANALOGICAL METHOD ON FRACTAL DIMENSION FOR THREE-DIMENSIONAL FRACTURE TORTUOSITY IN COAL BASED ON CT SCANNING Fractals (IF 4.7) Pub Date : 2023-08-02 GAOFENG LIU, ZHEN ZHANG, YUNXING CAO, XIAOMING WANG, HUAN LIU, BAOLIN LI, NIAN SI, WENBO GUAN
In this work, we have given an analogical method for estimating the fractal dimension for three-dimensional fracture tortuosity (3D-FT). The comparison and error analysis of analogical and rigorous methods on fractal dimension for 3D-FT were carried out in this work. The fractal dimension DT−R for 3D-FT from the proposed analogical method is the function of 3D fracture average tortuosity (τav) and
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WEAK TANGENTS ON CLOSED POPCORN GRAPHS Fractals (IF 4.7) Pub Date : 2023-08-02 HAIPENG CHEN, LIXUAN ZHENG
Given 0
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DYNAMIC HYPERLEDGER NFT ON FEDERATED LEARNING FOR PSYCHIATRIC SERVICES IN THE COVID-19 TIMES Fractals (IF 4.7) Pub Date : 2023-08-01 RICARDO CARREÑO AGUILERA, ADAN ACOSTA BANDA, MIGUEL PATIÑO ORTIZ, JULIAN PATIÑO ORTIZ
This paper proposes an innovative method to take advantage of Blockchain Convolutional Neural Networks (BCNNs) in Emotion Recognition (ER). Based on Artificial Intelligence, this proposal uses audio-visual emotion patterns to determine psychiatric profiles to attend to the most urgent as a priority. BCNN architectures were used to identify emergency patterns. The results indicate that the proposed
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HAUSDORFF DIMENSIONS OF FLOWER NETWORKS AND HANOI GRAPHS Fractals (IF 4.7) Pub Date : 2023-07-29 QINGCHENG ZENG, LIFENG XI
Zeng and Xi introduced the Hausdorff dimension of a family of networks and investigated the dimensions of touching networks. In this paper, using the self-similarity and induction we obtain the Hausdorff dimension of flower networks and Hanoi graphs, which are not touching networks.
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FRACTAL DIMENSIONS OF SETS DEFINED BY DIGIT RESTRICTIONS IN ℝ2 Fractals (IF 4.7) Pub Date : 2023-07-29 LIPENG WANG, WENXIA LI
We introduce a class of sets defined by digit restrictions in ℝ2 and study its fractal dimensions. Let ES,D be a set defined by digit restrictions in ℝ2. We obtain the Hausdorff and lower box dimensions of ES,D. Under some condition, we gain the packing and upper box dimensions of ES,D. We get the Assouad dimension of ES,D and show that it is 2 if and only if ES,D contains arbitrarily large arithmetic
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Comparison of energy conditions in general relativity and modified theories of gravity Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-07-27 H. Rizwana Kausar, Amal Majid, Hafsa Jameel
To make a comparison of energy conditions in the theory of general relativity and in the modified theories, we have considered f(R), f(R,T) and f(R,T,Q) theories (where R and T are the Ricci scalar and trace of the energy–momentum tensor, respectively, while Q=TabRab) to test the validity of all the four energy conditions. These energy conditions had been derived to check the viability of cosmological
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The generalized weakly Ricci symmetric structure Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-07-27 Haradhan Kundu, Kanak Kanti Baishya, Indranil Roy
This paper attempts to study some geometric properties along with the existence of a generalized weakly Ricci symmetric manifold and find out the reduced form of defining conditions of such a manifold. It is observed that every generalized weakly Ricci symmetric manifold is an almost generalized pseudo-Ricci symmetric manifold. We also find out the conditions for which a weakly Ricci symmetric manifold
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Implications of Palatini gravity for inflation and beyond Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-07-25 Ioannis D. Gialamas, Alexandros Karam, Thomas D. Pappas, Eemeli Tomberg
In this paper, we present an introduction to cosmic inflation in the framework of Palatini gravity, which provides an intriguing alternative to the conventional metric formulation of gravity. In the latter, only the metric specifies the spacetime geometry, whereas in the former, the metric and the spacetime connection are independent variables—an option that can result in a gravity theory distinct
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Nonextensive Gross Pitaevskii Equation Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-07-25 Mahnaz Maleki, Hosein Mohammadzadeh, Zahra Ebadi
In this paper, we consider the generalization of Gross Pitaevskii equation for condensate of bosons with nonextensive statistics. First, we use the non-additive methods and formalism to obtain the well-known Schrödinger equation. Using a suitable Hamiltonian for condensate phase and minimizing the free energy of the system by non-additive formalism, we work out the nonextensive Gross Pitaevskii equation
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Fermions tunneling of Kerr–Newman–de Sitter black hole in Lorentz violation theory Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-07-25 Ningthoujam Media, Y. Onika Laxmi, T. Ibungochouba Singh
In this paper, the tunneling of fermions near the event horizon of Kerr–Newman–de Sitter (KNdS) black hole is investigated in frame dragging coordinate systems, Eddington coordinate system and Painleve coordinate system by using Dirac equation with Lorentz violation theory, Feynman prescription and WKB approximation. The Hawking temperature, heat capacity and change in black hole entropy of the black
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ACCURATE FORMULAS OF HYPER-WIENER INDICES OF SIERPIŃSKI SKELETON NETWORKS Fractals (IF 4.7) Pub Date : 2023-07-27 Qin Wang, Qingcheng Zeng
The hyper-Wiener index on a graph is an important topological invariant that is defined as one half of the sum of the distances and square distances between all pairs of vertices of a graph. In this paper, we develop the discrete version of finite pattern to compute the accurate formulas of the hyper-Wiener indices of the Sierpiński skeleton networks.
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Generalization of compressible fluid equations in terms of complexified octonions Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-07-24 Süleyman Demir, Murat Tanışlı, Mustafa Emre Kansu
Using the attractive properties of octonion algebra, an alternative formulation has been proposed for the Maxwell-type equations of compressible fluids. Although the origins of electromagnetic theory and fluid mechanics are completely different, a series of suitable and elegant 8-dimensional equations have been derived in a form similar to electromagnetic, gravitational counterparts previously given
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General teleparallel metrical geometries Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-07-24 Muzaffer Adak, Tekin Dereli, Tomi S. Koivisto, Caglar Pala
In the conventional formulation of general relativity, gravity is represented by the metric curvature of Riemannian geometry. There are also alternative formulations in flat affine geometries, wherein the gravitational dynamics is instead described by torsion and nonmetricity. These so-called general teleparallel geometries may also have applications in material physics, such as the study of crystal
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Exploring the bouncing cosmological models in symmetric teleparallel gravity Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-07-24 Alfred Y. Shaikh
In this study, the bouncing cosmological models have been presented in the non-metricity-based gravitational theory, the f(Q) gravity, where Q be the non-metricity scalar. The two bouncing cosmological models, one in which the Lagrangian f(Q) is assumed to have a linear dependence on Q and the other in which it has a polynomial functional form have been shown. It has been obtained that the parameters
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Relativistic configurations of Tolman stellar spheres in f(𝒢,𝒯 ) gravity Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-07-24 Tayyaba Naz, Adnan Malik, Dania Gillani, Fatemah Mofarreh
This study is devoted to investigate the formation of compact stars using Tolman–Kuchowicz space-time in f(𝒢,𝒯) gravity. By taking into account the physically reliable formulations of metric potentials, ξ = Br2+2lnC and η = ln(1+ar2+br4), we investigate the equation of motion for spherically symmetric space-time in the presence of an anisotropic matter distribution. Furthermore, matching conditions
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Non-commutative wormhole in non-minimal curvature–matter coupling of f(R) gravity with Gaussian and Lorentzian distributions Int. J. Geom. Methods Mod. Phys. (IF 1.8) Pub Date : 2023-07-22 Ujjal Debnath, Niyaz Uddin Molla, Anirudh Pradhan
In this work, we construct two new wormhole solutions in the theory dealing with non-minimal coupling between curvature and matter. We take into account an explicitly non-minimal coupling between an arbitrary function of scalar curvature R and the Lagrangian density of matter. For this purpose, we discuss the Wormhole geometries inspired by non-minimal curvature coupling in f(R) gravity for linear