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Fractal Fractional Order Operators in Computational Techniques for Mathematical Models in Epidemiology 被引量:1
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作者 Muhammad Farman Ali Akgül +2 位作者 Mir Sajjad Hashemi Liliana Guran Amelia Bucur 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1385-1403,共19页
New fractional operators, the COVID-19 model has been studied in this paper. By using different numericaltechniques and the time fractional parameters, the mechanical characteristics of the fractional order model arei... New fractional operators, the COVID-19 model has been studied in this paper. By using different numericaltechniques and the time fractional parameters, the mechanical characteristics of the fractional order model areidentified. The uniqueness and existence have been established. Themodel’sUlam-Hyers stability analysis has beenfound. In order to justify the theoretical results, numerical simulations are carried out for the presented methodin the range of fractional order to show the implications of fractional and fractal orders.We applied very effectivenumerical techniques to obtain the solutions of themodel and simulations. Also, we present conditions of existencefor a solution to the proposed epidemicmodel and to calculate the reproduction number in certain state conditionsof the analyzed dynamic system. COVID-19 fractional order model for the case of Wuhan, China, is offered foranalysis with simulations in order to determine the possible efficacy of Coronavirus disease transmission in theCommunity. For this reason, we employed the COVID-19 fractal fractional derivative model in the example ofWuhan, China, with the given beginning conditions. In conclusion, again the mathematical models with fractionaloperators can facilitate the improvement of decision-making for measures to be taken in the management of anepidemic situation. 展开更多
关键词 COVID-19 model fractal-fractional operator Ulam-Hyers stability existence and uniqueness numerical simulation
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Existence and Uniqueness Results for a Fully Third-Order Boundary Value Problem
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作者 Xiaoming Liu Yongxiang Li 《Advances in Pure Mathematics》 2023年第8期495-503,共14页
The boundary value problems of the third-order ordinary differential equation have many practical application backgrounds and their some special cases have been studied by many authors. However, few scholars have stud... The boundary value problems of the third-order ordinary differential equation have many practical application backgrounds and their some special cases have been studied by many authors. However, few scholars have studied the boundary value problems of the complete third-order differential equations u′′′(t) = f (t,u(t),u′(t),u′′(t)). In this paper, we discuss the existence and uniqueness of solutions and positive solutions of the fully third-order ordinary differential equation on [0,1] with the boundary condition u(0) = u′(1) = u′′(1) = 0. Under some inequality conditions on nonlinearity f some new existence and uniqueness results of solutions and positive solutions are obtained. 展开更多
关键词 Fully Third-Order BVP SOLUTION Positive Solution Existence and uniqueness Inequality Conditions
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Existence of a Hölder Continuous Extension on Embedded Balls of the 3-Torus for the Periodic Navier Stokes Equations
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作者 Terry E. Moschandreou 《Advances in Pure Mathematics》 2024年第2期118-138,共21页
This article gives a general model using specific periodic special functions, which is degenerate elliptic Weierstrass P functions whose presence in the governing equations through the forcing terms simplify the perio... This article gives a general model using specific periodic special functions, which is degenerate elliptic Weierstrass P functions whose presence in the governing equations through the forcing terms simplify the periodic Navier Stokes equations (PNS) at the centers of cells of the 3-Torus. Satisfying a divergence-free vector field and periodic boundary conditions respectively with a general spatio-temporal forcing term which is smooth and spatially periodic, the existence of solutions which have finite time singularities can occur starting with the first derivative and higher with respect to time. The existence of a subspace of the solution space where v<sub>3</sub> is continuous and {C, y<sub>1</sub>, y<sub>1</sub><sup>2</sup>}, is linearly independent in the additive argument of the solution in terms of the Lambert W function, (y<sub>1</sub><sup>2</sup>=y<sub>2</sub>, C∈R) together with the condition v<sub>2</sub>=-2y<sub>1</sub>v<sub>1</sub>. On this subspace, the Biot Savart Law holds exactly [see Section 2 (Equation (13))]. Also on this subspace, an expression X (part of PNS equations) vanishes which contains all the expressions in derivatives of v<sub>1</sub> and v<sub>2</sub> and the forcing terms in the plane which are related as with the cancellation of all such terms in governing PDE. The y<sub>3</sub> component forcing term is arbitrarily small in ε ball where Weierstrass P functions touch the center of the ball both for inviscid and viscous cases. As a result, a significant simplification occurs with a v<sub>3 </sub>only governing PDE resulting. With viscosity present as v changes from zero to the fully viscous case at v =1 the solution for v<sub>3</sub> reaches a peak in the third component y<sub>3</sub>. Consequently, there exists a dipole which is not centered at the center of the cell of the Lattice. Hence since the dipole by definition has an equal in magnitude positive and negative peak in y<sub>3</sub>, then the dipole Riemann cut-off surface is covered by a closed surface which is the sphere and where a given cell of dimensions [-1, 1]<sup>3</sup> is circumscribed on a sphere of radius 1. For such a closed surface containing a dipole it necessarily follows that the flux at the surface of the sphere of v<sub>3</sub> wrt to surface normal n is zero including at the points where the surface of sphere touches the cube walls. At the finite time singularity on the sphere a rotation boundary condition is deduced. It is shown that v<sub>3</sub> is spatially finite on the Riemann Sphere and the forcing is oscillatory in y<sub>3</sub> component if the velocity v3</sub> is. It is true that . A boundary condition on the sphere shows the rotation of a sphere of viscous fluid. Finally on the sphere a solution for v3</sub> is obtained which is proven to be Hölder continuous and it is shown that it is possible to extend Hölder continuity on the sphere uniquely to all of the interior of the ball. 展开更多
关键词 Navier-Stokes PNS 3-Torus PERIODIC Ball Sphere Hölder CONTINUOUS Riemann-Surface uniqueness
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2023:A year of accomplishments for the 13 Science Citation Index Expanded-and Emerging Sources Citation Index-indexed Baishideng journals
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作者 Jin-Lei Wang Jia-Ping Yan +22 位作者 Jia-Ru Fan Xiang Li Xu Guo Jia-Wei Li Yun-Xiaojian Wu Jing-Jie Wang Yu-Lu Chen Li Li Cong Lin Xin-Liang Qu Ji-Hong Liu Yan-Liang Zhang Ying-Yi Yuan Hua-Ge Yu Yu-Xi Chen Yi-Xuan Cai Xiang-Di Zhang Si Zhao Zi-Hang Xu Li Ma Na Ma Diao-Mei Guo Lian-Sheng Ma 《World Journal of Gastroenterology》 SCIE CAS 2024年第1期9-16,共8页
In 2023,Baishideng Publishing Group(Baishideng)routinely published 47 openaccess journals,including 46 English-language journals and 1 Chinese-language journal.Our successes were accomplished through the collective de... In 2023,Baishideng Publishing Group(Baishideng)routinely published 47 openaccess journals,including 46 English-language journals and 1 Chinese-language journal.Our successes were accomplished through the collective dedicated efforts of Baishideng staffs,Editorial Board Members,and Peer Reviewers.Among these 47 Baishideng journals,7 are included in the Science Citation Index Expanded(SCIE)and 6 in the Emerging Sources Citation Index(ESCI).With the support of Baishideng authors,company staffs,Editorial Board Members,and Peer Reviewers,the publication work of 2023 is about to be successfully completed.This editorial summarizes the 2023 activities and accomplishments of the 13 SCIEand ESCI-indexed Baishideng journals,outlines the Baishideng publishing policy changes and additions made this year,and highlights the unique advantages of Baishideng journals. 展开更多
关键词 Baishideng Publishing Group Journal Impact Factor Open access Policy changes Policy additions Unique advantages Anxiety disorders Colorectal cancer Inflammatory bowel disease Hepatocellular carcinoma Gut microbes Atrial fibrillation
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UNIQUENESS PROBLEM WITH TRUNCATED MULTIPLICITIES OF MEROMORPHIC MAPPINGS FOR MOVING TARGETS 被引量:4
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作者 陈志华 李燕华 颜启明 《Acta Mathematica Scientia》 SCIE CSCD 2007年第3期625-634,共10页
In this article, two uniqueness theorems of meromorphic mappings on moving targets with truncated multiplicities are proved.
关键词 Moving targets uniqueness theorem value distribution
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UNIQUENESS PROBLEM FOR MEROMORPHIC MAPPINGS IN SEVERAL COMPLEX VARIABLES INTO P^N(C) WITH TRUNCATED MULTIPLICITIES 被引量:4
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作者 涂振汉 王中华 《Acta Mathematica Scientia》 SCIE CSCD 2013年第1期122-130,共9页
This paper proves some uniqueness theorems for meromorphic mappings in several complex variables into the complex projective space p^N(C) with truncated multiplicities, and our results improve some earlier work.
关键词 meromorphic mappings truncated multiplicities uniqueness theorems value distribution theory
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Uniqueness Theorems for Meromorphic Functions of Order Less than One 被引量:14
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作者 李玉华 《Northeastern Mathematical Journal》 CSCD 2000年第4期411-416,共6页
In this paper we study the uniqueness of certain meromorphic functions. It is shown that any two nonconstant meromorphic functions of order less than one, that share four values IM or six values SCM, must be identical... In this paper we study the uniqueness of certain meromorphic functions. It is shown that any two nonconstant meromorphic functions of order less than one, that share four values IM or six values SCM, must be identical. As a consequence, a result due to W. W. Adams and E. G. Straus is generalized. 展开更多
关键词 meromorphic function IM sharing value uniqueness
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EXISTENCE, BOUNDEDNESS AND UNIQUENESS OF WEAK SOLUTION FOR THE THERMISTOR PROBLEM WITH MIXED BOUNDARV CONDITIONS 被引量:3
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作者 管平 《Acta Mathematica Scientia》 SCIE CSCD 1998年第3期326-332,共7页
The thermistor problem is a coupled system of nonlinear PDEs with mixed boundary conditions. The goal of this paper is to study the existence, boundedness and uniqueness of the weak solution for this problem.
关键词 nonlinear partial differential equations existence boundedness uniqueness
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EXISTENCE AND UNIQUENESS FOR THIRD ORDER NONLINEAR BOUNDARY VALUE PROBLEMS 被引量:5
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作者 WANG GUOCAN Department of Basic Science, Dalian Institute of Railway Technology, Dalian 116022 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1996年第1期7-16,共10页
In this paper, the existence and uniqueness of solutions for boundary valueproblem x′′′=f(t, x, x′, x″), x(0)=A, x′(0)=B, g(x′(1), x″(1))=0 are studied byusing Volterra type operator and upper and lower soluti... In this paper, the existence and uniqueness of solutions for boundary valueproblem x′′′=f(t, x, x′, x″), x(0)=A, x′(0)=B, g(x′(1), x″(1))=0 are studied byusing Volterra type operator and upper and lower solutions. Our results improve someknown works. 展开更多
关键词 Third order nonlinear boundary value problem existence and uniqueness Volterra type operator upper and lower solutions.
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UNIQUENESS FOR SOLUTIONS OF NONHOMOGENEOUS A -HARMONIC EQUATIONS WITH VERY WEAK BOUNDARY VALUES 被引量:2
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作者 高红亚 叶玉全 谢素英 《Journal of Shanghai Jiaotong university(Science)》 EI 2001年第1期78-80,共3页
A uniqueness result for nonhomogeneous quasilinear elliptic partial differential equations with very weak boundary values was proved.
关键词 uniqueness A harmonic equation weak solution very weak boundary values
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HOPF BIFURCATION AND UNIQUENESS OF LIMIT CYCLE FOR A CLASS OF QUARTIC SYSTEM 被引量:2
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作者 Zhan Qingyi Xie Xiangdong +1 位作者 Wu Chengqiang Qiu Shulin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2007年第4期388-392,共5页
This paper studies a class of quartic system which is more general and realistic than the quartic accompanying system.x'=-y+ex+lx^2+mxy+ny^2,y'=x(1-Ay)(1+Cy^2),(*)where C 〉 0. Sufficient conditions are ... This paper studies a class of quartic system which is more general and realistic than the quartic accompanying system.x'=-y+ex+lx^2+mxy+ny^2,y'=x(1-Ay)(1+Cy^2),(*)where C 〉 0. Sufficient conditions are obtained for the uniqueness of limit cycle of system (*) and some more in-depth conclusion such as Hopf bifurcation. 展开更多
关键词 accompanying system bifurcation limit cycle uniqueness.
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A NOTE ON THE UNIQUENESS AND THE NON-DEGENERACY OF POSITIVE RADIAL SOLUTIONS FOR SEMILINEAR ELLIPTIC PROBLEMS AND ITS APPLICATION 被引量:1
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作者 Shinji ADACHI Masataka SHIBATA Tatsuya WATANABE 《Acta Mathematica Scientia》 SCIE CSCD 2018年第4期1121-1142,共22页
In this paper, we are concerned with the uniqueness and the non-degeneracy of positive radial solutions for a class of semilinear elliptic equations. Using detailed ODE anal- ysis, we extend previous results to cases ... In this paper, we are concerned with the uniqueness and the non-degeneracy of positive radial solutions for a class of semilinear elliptic equations. Using detailed ODE anal- ysis, we extend previous results to cases where nonlinear terms may have sublinear growth. As an application, we obtain the uniqueness and the non-degeneracy of ground states for modified SchrSdinger equations. 展开更多
关键词 positive radial solution uniqueness NON-DEGENERACY shooting method
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EXISTENCE AND UNIQUENESS OF POSITIVE SOLUTION FOR NONLINEAR SINGULAR 2mth-ORDER CONTINUOUS AND DISCRETE LIDSTONE BOUNDARY VALUE PROBLEMS 被引量:1
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作者 苑成军 文香丹 蒋达清 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期281-291,共11页
By fixed point theorem of a mixed monotone operators, we study Lidstone boundary value problems to nonlinear singular 2mth-order differential and difference equations, and provide sufficient conditions for the existen... By fixed point theorem of a mixed monotone operators, we study Lidstone boundary value problems to nonlinear singular 2mth-order differential and difference equations, and provide sufficient conditions for the existence and uniqueness of positive solution to Lidstone boundary value problem for 2mth-order ordinary differential equations and 2mth-order difference equations. The nonlinear term in the differential and difference equation may be singular. 展开更多
关键词 Mixed monotone operator fixed point theorem boundary value problems existence uniqueness
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ON THE UNIQUENESS OF BOUNDARY INTEGRAL EQUATION FOR THE EXTERIOR HELMHOLTZ PROBLEM 被引量:1
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作者 王清 徐博侯 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第10期965-971,共7页
From the point of view of energy analysis, the cause that the uniqueness of the boundary integral equation induced from the exterior Helmholtz problem does not hold is investigated in this paper. It is proved that the... From the point of view of energy analysis, the cause that the uniqueness of the boundary integral equation induced from the exterior Helmholtz problem does not hold is investigated in this paper. It is proved that the Sommerfeld's condition at the infinity is changed so that it is suitable not only for the radiative wave but also for the absorptive wave when we use the boundary integral equation to describe the exterior Helmholtz problem. There fore, the total energy of the system is conservative. The mathematical dealings to guarantee the uniqueness are discussed based upon this explanation. 展开更多
关键词 exterior Helmholtz problem boundary integral equation uniqueness
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EXISTENCE AND UNIQUENESS RESULTS FOR BOUNDARY VALUE PROBLEMS OF HIGHER ORDER FRACTIONAL INTEGRO-DIFFERENTIAL EQUATIONS INVOLVING GRONWALL'S INEQUALITY IN BANACH SPACES 被引量:2
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作者 Dimplekumar N. CHALISHAJAR K. KARTHIKEYAN 《Acta Mathematica Scientia》 SCIE CSCD 2013年第3期758-772,共15页
We study boundary value problems for fractional integro-differential equations involving Caputo derivative of order α∈ (n-1, n) in Banach spaces. Existence and uniqueness results of solutions are established by vi... We study boundary value problems for fractional integro-differential equations involving Caputo derivative of order α∈ (n-1, n) in Banach spaces. Existence and uniqueness results of solutions are established by virtue of the Holder's inequality, a suitable singular Cronwall's inequality and fixed point theorem via a priori estimate method. At last, examples are given to illustrate the results. 展开更多
关键词 Boundary value problems fractional order integro-differential equations bound-ary value problems existence and uniqueness singular gronwall inequality fixed point theorem
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Local Existence and Uniqueness Theorem for a Nonlinear Schr&#246;dinger Equation with Robin Inhomogeneous Boundary Condition 被引量:2
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作者 Charles Bu 《Journal of Applied Mathematics and Physics》 2020年第3期464-469,共6页
In recent years, a vast amount of work has been done on initial value problems for important nonlinear evolution equations like the nonlinear Schr&#246;dinger equation (NLS) and the Korteweg-de Vries equation (KdV... In recent years, a vast amount of work has been done on initial value problems for important nonlinear evolution equations like the nonlinear Schr&#246;dinger equation (NLS) and the Korteweg-de Vries equation (KdV). No comparable attention has been given to mixed initial-boundary value problems for these equations, i.e. forced nonlinear systems. But in many cases of physical interest, the mathematical model leads precisely to the forced problems. For example, the launching of solitary waves in a shallow water channel, the excitation of ion-acoustic solitons in a double plasma machine, etc. In this article, we present the PDE (Partial Differential Equation) method to study the following iut = uxx - g|u|pu, g ∈ R, p > 3, x?∈ Ω = [0,L], 0 ≤?t?u (x,0) = u0 (x) ∈?H2 (Ω) and Robin inhomogeneous boundary condition ux (0,t) + αu (0,t) = R1(t), t ≥ 0 and ux (L,t) + αu (L,t) = R2 (t), t ≥ 0 (here?α?is a real number). The equation is posed in a semi-infinite strip on a finite domain Ω. Such problems are called forced problems and have many applications in other fields like physics and chemistry. The main tool of PDE method is semi-group theory. We are able to prove local existence and uniqueness theorem for the nonlinear Schr&#246;dinger equation under initial condition and Robin inhomogeneous boundary condition. 展开更多
关键词 NONLINEAR SCHRODINGER Equation INHOMOGENEOUS Robin Boundary Condition Existence and uniqueness CLASSICAL Solution
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EXISTENCE AND UNIQUENESS OF SOLUTIONS TO THE DYNAMIC EQUATIONS FOR KOITER SHELLS 被引量:1
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作者 肖黎明 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第7期100-105,共6页
In this paper, the dynamic equations for Koiter shells have been studied by Galerkin method, the existence and uniqueness to the solutions are proved.
关键词 Galerkin method the dynamic equations for Koiter shells existence and uniqueness
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Existence and Uniqueness of Global Smooth Solutions for Vlasov Maxwell Equations 被引量:1
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作者 Lukas Degu Petros 《Advances in Pure Mathematics》 2018年第1期45-76,共32页
Global existence of classical solutions to the relativistic Vlasov-Maxwell system, given sufficiently regular initial data, is a long-standing open problem. The aim of this project is to present in details the results... Global existence of classical solutions to the relativistic Vlasov-Maxwell system, given sufficiently regular initial data, is a long-standing open problem. The aim of this project is to present in details the results of a paper published in 1986 by Robert Glassey and Walter Strauss. In that paper, a sufficient condition for the global existence of a smooth solution to the relativistic Vlasov-Maxwell system is derived. In the following, the resulting theorem is proved by taking initial data , . A small data global existence result is presented as well. 展开更多
关键词 MAXWELL EQUATION VLASOV EQUATION Existence and uniqueness
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Existence and Uniqueness of Almost Periodic Solutions for Some Infinite Delay Integral Equations 被引量:1
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作者 XU Jian-zhong ZHANG Yu-chuan ZHOU Zong-fu 《Chinese Quarterly Journal of Mathematics》 2018年第2期166-171,共6页
In this paper, the existence and uniqueness of almost periodic solutions for some infinite delay integral equations are discussed. By using Krasnoselskii fixed point theorem,some new results are obtained.
关键词 Almost periodic solution Existence uniqueness Delay integral equation Krasnoselskii fixed point theorem
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Uniqueness of BV Entropy Solutions for Higher Dimensional Quasilinear Parabolic Equations with Arbitrary Degeneracy 被引量:1
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作者 伍卓群 尹景学 +1 位作者 雷沛东 严子谦 《Northeastern Mathematical Journal》 CSCD 2002年第1期1-4,共4页
We are concerned with the uniqueness of solutions of the Cauchy problemand a(s),b(s) are appropriately smooth.Since a(s) is allowed to have zero points, we call them points of degeneracy of (1), the equation (1) does ... We are concerned with the uniqueness of solutions of the Cauchy problemand a(s),b(s) are appropriately smooth.Since a(s) is allowed to have zero points, we call them points of degeneracy of (1), the equation (1) does not admit classical solutions in general. The solutions of (1) even might be discontinuous, whenever the set E = {s : a(s) = 0} includes interior points.Equations with degeneracy arise from a wide variety of diffusive processes in nature 展开更多
关键词 uniqueness BV entropy solution parabolic equation arbitrary degeneracy
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