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A Stochastic Model to Assess the Epidemiological Impact of Vaccine Booster Doses on COVID-19 and Viral Hepatitis B Co-Dynamics with Real Data
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作者 Andrew Omame Mujahid Abbas Dumitru Baleanu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2973-3012,共40页
A patient co-infected with COVID-19 and viral hepatitis B can be atmore risk of severe complications than the one infected with a single infection.This study develops a comprehensive stochastic model to assess the epi... A patient co-infected with COVID-19 and viral hepatitis B can be atmore risk of severe complications than the one infected with a single infection.This study develops a comprehensive stochastic model to assess the epidemiological impact of vaccine booster doses on the co-dynamics of viral hepatitis B and COVID-19.The model is fitted to real COVID-19 data from Pakistan.The proposed model incorporates logistic growth and saturated incidence functions.Rigorous analyses using the tools of stochastic calculus,are performed to study appropriate conditions for the existence of unique global solutions,stationary distribution in the sense of ergodicity and disease extinction.The stochastic threshold estimated from the data fitting is given by:R_(0)^(S)=3.0651.Numerical assessments are implemented to illustrate the impact of double-dose vaccination and saturated incidence functions on the dynamics of both diseases.The effects of stochastic white noise intensities are also highlighted. 展开更多
关键词 Viral hepatitis B COVID-19 stochastic model EXTINCTION ERGODICITY real data
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Entropies of the Y-Junction Type Nanostructures
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作者 Ricai Luo Aisha Javed +3 位作者 Muhammad Azeem Muhammad Kamran Jamil Hassan Raza Muhammad Yasir Ilyas 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2665-2679,共15页
Recent research on nanostructures has demonstrated their importance and application in a variety of fields.Nanostructures are used directly or indirectly in drug delivery systems,medicine and pharmaceuticals,biologica... Recent research on nanostructures has demonstrated their importance and application in a variety of fields.Nanostructures are used directly or indirectly in drug delivery systems,medicine and pharmaceuticals,biological sensors,photodetectors,transistors,optical and electronic devices,and so on.The discovery of carbon nanotubes with Y-shaped junctions is motivated by the development of future advanced electronic devices.Because of their interactionwithY-junctions,electronic switches,amplifiers,and three-terminal transistors are of particular interest.Entropy is a concept that determines the uncertainty of a system or network.Entropy concepts are also used in biology,chemistry,and applied mathematics.Based on the requirements,entropy in the form of a graph can be classified into several types.In 1955,graph-based entropy was introduced.One of the types of entropy is edgeweighted entropy.We examined the abstract form of Y-shaped junctions in this study.Some edge-weight-based entropy formulas for the generic view of Y-shaped junctions were created,and some edge-weighted and topological index-based concepts for Y-shaped junctions were discussed in the present paper. 展开更多
关键词 Y-shaped junctions three-terminal junctions nanostuctures ENTROPY carbon nanotube
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Unique Solution of Integral Equations via Intuitionistic Extended Fuzzy b-Metric-Like Spaces
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作者 Naeem Saleem Khalil Javed +4 位作者 Fahim Uddin Umar Ishtiaq Khalil Ahmed Thabet Abdeljawad Manar A.Alqudah 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期109-131,共23页
In this manuscript,our goal is to introduce the notion of intuitionistic extended fuzzy b-metric-like spaces.We establish some fixed point theorems in this setting.Also,we plot some graphs of an example of obtained re... In this manuscript,our goal is to introduce the notion of intuitionistic extended fuzzy b-metric-like spaces.We establish some fixed point theorems in this setting.Also,we plot some graphs of an example of obtained result for better understanding.We use the concepts of continuous triangular norms and continuous triangular conorms in an intuitionistic fuzzy metric-like space.Triangular norms are used to generalize with the probability distribution of triangle inequality in metric space conditions.Triangular conorms are known as dual operations of triangular norms.The obtained results boost the approaches of existing ones in the literature and are supported by some examples and applications. 展开更多
关键词 Fixed point extended fuzzy b-metric like space intuitionistic extended fuzzy b-metric-like space integral equation
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Unsteady flow of viscoelastic fluid between two cylinders using fractional Maxwell model 被引量:2
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作者 Muhammad Jamil Constantin Fetecau Corina Fetecau 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第2期274-280,共7页
The unsteady flow of an incompressible fractional Maxwell fluid between two infinite coaxial cylinders is studied by means of integral transforms. The motion of the fluid is due to the inner cylinder that applies a ti... The unsteady flow of an incompressible fractional Maxwell fluid between two infinite coaxial cylinders is studied by means of integral transforms. The motion of the fluid is due to the inner cylinder that applies a time dependent tor- sional shear to the fluid. The exact solutions for velocity and shear stress are presented in series form in terms of some generalized functions. They can easily be particularized to give similar solutions for Maxwell and Newtonian fluids. Fi- nally, the influence of pertinent parameters on the fluid motion, as well as a comparison between models, is highlighted by graphical illustrations. 展开更多
关键词 Maxwell fluid Fractional derivative Exact so- lutions Velocity field Shear stress Laplace and Hankel transforms
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Magnetohydrodynamic approach of non-Newtonian blood flow with magnetic particles in stenosed artery 被引量:1
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作者 I. A. MIRZAt M. ABDULHAMEED S. SHAFIE 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第3期379-392,共14页
The non-Newtonian blood flow, together with magnetic particles in a stenosed artery, is studied using a magneto-hydrodynamic approach. The wall slip condition is also considered. Approximate solutions are obtained in ... The non-Newtonian blood flow, together with magnetic particles in a stenosed artery, is studied using a magneto-hydrodynamic approach. The wall slip condition is also considered. Approximate solutions are obtained in series forms under the assumption that the Womersley frequency parameter has small values. Using an integral transform method, analytical solutions for any values of the Womersley parameter are obtained.Numerical simulations are performed using MATHCAD to study the influence of stenosis and magnetic field on the flow parameters. When entering the stenosed area, blood velocity increases slightly, but increases considerably and reaches its maximum value in the stenosis throat. It is concluded that the magnitude of axial velocity varies considerably when the applied magnetic field is strong. The magnitude of maximum fluid velocity is high in the case of weak magnetic fields. This is due to the Lorentz's force that opposes motion of an electrically conducting fluid. The effect of externally transverse magnetic field is to decelerate the flow of blood. The shear stress consistently decreases in the presence of a magnetic field with increasing intensity. 展开更多
关键词 BINGHAM plastic fluid magnetic particle blood flow magnetohydrodynam-ics ARTERY STENOSIS
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Some exact solutions of the oscillatory motion of a generalized second grade fluid in an annular region of two cylinders 被引量:4
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作者 A.Mahmood C.Fetecau +1 位作者 N.A.Khan M.Jamil 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第4期541-550,共10页
The velocity field and the associated shear stress corresponding to the longitudinal oscillatory flow of a generalized second grade fluid, between two infinite coaxial circular cylinders, are determined by means of th... The velocity field and the associated shear stress corresponding to the longitudinal oscillatory flow of a generalized second grade fluid, between two infinite coaxial circular cylinders, are determined by means of the Laplace and Hankel transforms. Initially, the fluid and cylinders are at rest and at t = 0+ both cylinders suddenly begin to oscillate along their common axis with simple harmonic motions having angular frequencies Ω1 and Ω2. The solutions that have been obtained are presented under integral and series forms in terms of the generalized G and R functions and satisfy the governing differential equation and all imposed initial and boundary conditions. The respective solutions for the motion between the cylinders, when one of them is at rest, can be obtained from our general solutions. Furthermore, the corresponding solutions for the similar flow of ordinary second grade fluid and Newtonian fluid are also obtained as limiting cases of our general solutions. At the end, the effect of different parameters on the flow of ordinary second grade and generalized second grade fluid are investigated graphically by plotting velocity profiles. 展开更多
关键词 Generalized second grade fluid Velocity field Shear stress Longitudinal oscillatory flow Laplace and Hankel transforms
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A note on the unsteady flow of a fractional Maxwell fluid through a circular cylinder
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作者 M.Athar A.U.Awan Corina Fetecau 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第2期308-314,共7页
In this note the velocity field and the adequate shear stress corresponding to the unsteady flow of a frac- tional Maxwell fluid due to a constantly accelerating circular cylinder have been determined by means of the ... In this note the velocity field and the adequate shear stress corresponding to the unsteady flow of a frac- tional Maxwell fluid due to a constantly accelerating circular cylinder have been determined by means of the Laplace and finite Hankel transforms. The obtained solutions satisfy all imposed initial and boundary conditions. They can easily be reduced to give similar solutions for ordinary Maxwell and Newtonian fluids. Finally, the influence of pertinent param- eters on the fluid motion, as well as a comparison between models, is underlined by graphical illustrations. 展开更多
关键词 Fractional Maxwell fluid Velocity field Shear stress Exact solutions
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Exact analytical solutions for axial flow of a fractional second grade fluid between two coaxial cylinders
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作者 M.Imran M.Kamran M.Athar 《Theoretical & Applied Mechanics Letters》 CAS 2011年第2期41-46,共6页
The velocity field and the adequate shear stress corresponding to the longitudinal flow of a fractional second grade fluid,between two infinite coaxial circular cylinders,are determined by applying the Laplace and fin... The velocity field and the adequate shear stress corresponding to the longitudinal flow of a fractional second grade fluid,between two infinite coaxial circular cylinders,are determined by applying the Laplace and finite Hankel transforms.Initially the fluid is at rest,and at time t=0^+, the inner cylinder suddenly begins to translate along the common axis with constant acceleration. The solutions that have been obtained are presented in terms of generalized G functions.Moreover, these solutions satisfy both the governing differential equations and all imposed initial and boundary conditions.The corresponding solutions for ordinary second grade and Newtonian fluids are obtained as limiting cases of the general solutions.Finally,some characteristics of the motion,as well as the influences of the material and fractional parameters on the fluid motion and a comparison between models,are underlined by graphical illustrations. 展开更多
关键词 second grade fluid fractional derivative longitudinal flow velocity field shear stress Laplace and finite Hankel transforms
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Exact solutions for the flow of second grade fluid in annulus between torsionally oscillating cylinders
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作者 Amir Mahmood Saima Parveen Najeeb Alam Khan 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第2期222-227,共6页
The velocity field and the associated shear stress corresponding to the torsional oscillatory flow of a second grade fluid, between two infinite coaxial circular cylinders, are determined by means of the Laplace and H... The velocity field and the associated shear stress corresponding to the torsional oscillatory flow of a second grade fluid, between two infinite coaxial circular cylinders, are determined by means of the Laplace and Hankel transforms. At time t = 0, the fluid and both the cylinders are at rest and at t = 0 + , cylinders suddenly begin to oscillate around their common axis in a simple harmonic way having angular frequencies ω 1 and ω 2 . The obtained solutions satisfy the governing differential equation and all imposed initial and boundary conditions. The solutions for the motion between the cylinders, when one of them is at rest, can be obtained from our general solutions. Furthermore, the corresponding solutions for Newtonian fluid are also obtained as limiting cases of our general solutions. 展开更多
关键词 Second grade fluid · Velocity field · Shear stress · Longitudinal oscillatory flow · Laplace and Hankel transforms
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Face Labelings of Klein-bottle Fullerenes
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作者 Martin BACA Maria NASEEM Ayesha SHABBIR 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2017年第2期277-286,共10页
关键词 Klein-bottle fullerene d-antimagic labeling super d-antimagic labeling
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General Solutions for Hydromagnetic Free Convection Flow over an Infinite Plate with Newtonian Heating, Mass Diffusion and Chemical Reaction
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作者 Constatin Fetecau Nehad Ali Shah Dumitru Vieru 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第12期768-782,共15页
The problem of hydromagnetic free convection flow over a moving infinite vertical plate with Newtonian heating, mass diffusion and chemical reaction in the presence of a heat source is completely solved. Radiative and... The problem of hydromagnetic free convection flow over a moving infinite vertical plate with Newtonian heating, mass diffusion and chemical reaction in the presence of a heat source is completely solved. Radiative and porous effects are not taken into consideration but they can be immediately included by a simple rescaling of Prandtl number and magnetic parameter. Exact general solutions for the dimensionless velocity and concentration fields and the corresponding Sherwood number and skin friction coefficient are determined under integral form in terms of error function or complementary error function of Gauss. They satisfy all imposed initial and boundary conditions and can generate exact solutions for any problem with technical relevance of this type. As an interesting completion, uncommon in the literature, the differential equations which describe the thermal, concentration and momentum boundary layer, as well as the exact expressions for the thicknesses of thermal, concentration or velocity boundary layers were determined.Numerical results have shown that the thermal boundary layer thickness decreases for increasing values of Prandtl number and the concentration boundary layer thickness is decreasing with Schmidt number. Finally, for illustration,three special cases are considered and the influence of physical parameters on some fundamental motions is graphically underlined and discussed. The required time to reach the flow according with post-transient solution(the steady-state),for cosine/sine oscillating concentrations on the boundary is graphically determined. It is found that, the presence of destructive chemical reaction improves this time for increasing values of chemical reaction parameter. 展开更多
关键词 hydromagnetic free convection Newtonian heating heat source mass diffusion chemical reaction general solutions
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Lexsegment Ideals Are Sequentially Cohen-Macaulay
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作者 Muhammad Ishaq 《Algebra Colloquium》 SCIE CSCD 2014年第4期551-560,共10页
The associated primes of an arbitrary lexsegment ideal I C S = K[x1,..., xn] are determined. As application it is shown that S/I is a pretty clean module, therefore S/I is sequentially Cohen-Mazaulay and satisfies Sta... The associated primes of an arbitrary lexsegment ideal I C S = K[x1,..., xn] are determined. As application it is shown that S/I is a pretty clean module, therefore S/I is sequentially Cohen-Mazaulay and satisfies Stanley's conjecture. 展开更多
关键词 lexsegment ideals primary decomposition pretty clean modules sequentiallyCohen-Macaulay ideals Stanley depth
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Indispensable Hibi Relations and Grobner Bases
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作者 Ayesha Asloob Qureshi ] 《Algebra Colloquium》 SCIE CSCD 2015年第4期567-580,共14页
In this paper we consider Hibi rings and Rees rings attached to a poset. We classify the ideal lattices of posets whose Hibi relations are indispensable and the ideal lattices of posets whose Hibi relations form a qua... In this paper we consider Hibi rings and Rees rings attached to a poset. We classify the ideal lattices of posets whose Hibi relations are indispensable and the ideal lattices of posets whose Hibi relations form a quadratic Grobner basis with respect to the rank lexicographic order. Similar classifications are obtained for Rees rings of Hibi ideals. 展开更多
关键词 Hibi rings Hibi relations Gr5bner bases LATTICES
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