Sergei Shmarev - Academia.edu (original) (raw)
Papers by Sergei Shmarev
Evolution Equations and Lagrangian Coordinates, 1997
Evolution Equations and Lagrangian Coordinates, 1997
Siberian Mathematical Journal, 1991
Energy Methods in Continuum Mechanics, 1996
ABSTRACT
Let Ω ⊂ R n be a regular domain and Φ(s) ∈ C loc (R) be a given function. If M ⊂ L 2 (0, T ; W 1 ... more Let Ω ⊂ R n be a regular domain and Φ(s) ∈ C loc (R) be a given function. If M ⊂ L 2 (0, T ; W 1 2 (Ω)) ∩ L∞(Ω × (0, T)) is bounded and the set {∂tΦ(v)| v ∈ M} is bounded in L 2 (0, T ; W −1 2 (Ω)), then there is a sequence {v k } ∈ M such that v k v ∈ L 2 (0, T ; W 1 2 (Ω)), and v k → v, Φ(v k) → Φ(v) a.e. in Ω T = Ω × (0, T). This assertion is applied to prove solvability of the one-dimensional initial and boundary-value problem for a degenerate parabolic equation arising in the Buckley-Leverett model of two-phase filtration. We prove existence and uniqueness of a weak solution, establish the property of finite speed of propagation and construct a self-similar solution.
Evolution Equations and Lagrangian Coordinates, 1997
Evolution Equations and Lagrangian Coordinates, 1997
Proceedings of the Steklov Institute of Mathematics, 2008
We study the Dirichlet problem for a class of nonlinear parabolic equations with nonstandard anis... more We study the Dirichlet problem for a class of nonlinear parabolic equations with nonstandard anisotropic growth conditions that generalize the evolutional p(x, t)-Laplacian. We study the property of extinction of solutions in finite time. In particular, we show that the extinction may take place even in the borderline case when the equation becomes linear as t → ∞.
Proceedings of the Steklov Institute of Mathematics, 2010
ABSTRACT The aim of this paper is to establish sufficient conditions of the finite time blow-up i... more ABSTRACT The aim of this paper is to establish sufficient conditions of the finite time blow-up in solutions of the homogeneous Dirichlet problem for the anisotropic parabolic equations with variable nonlinearity $ u_t = \sum\nolimits_{i = 1}^n {D_i (a_i (x,t)|D_i u|^{p^i (x) - 2} D_i u) + \sum\nolimits_{i = 1}^K {b_i (x,t)|u|^{\sigma _i (x,t) - 2} u} } $ u_t = \sum\nolimits_{i = 1}^n {D_i (a_i (x,t)|D_i u|^{p^i (x) - 2} D_i u) + \sum\nolimits_{i = 1}^K {b_i (x,t)|u|^{\sigma _i (x,t) - 2} u} } . Two different cases are studied. In the first case a i ≡ a i (x), p i ≡ 2, σ i ≡ σ i (x, t), and b i (x, t) ≥ 0. We show that in this case every solution corresponding to a “large” initial function blows up in finite time if there exists at least one j for which min σ j (x, t) > 2 and either b j > 0, or b j (x, t) ≥ 0 and Σπ b j −ρ(t)(x, t) dx < ∞ with some σ(t) > 0 depending on σ j . In the case of the quasilinear equation with the exponents p i and σ i depending only on x, we show that the solutions may blow up if min σ i ≥ max p i , b i ≥ 0, and there exists at least one j for which min σ j > max p j and b j > 0. We extend these results to a semilinear equation with nonlocal forcing terms and quasilinear equations which combine the absorption (b i ≤ 0) and reaction terms.
Journal of Mathematical Analysis and Applications, 2010
We study the property of finite time vanishing of solutions of the homogeneous Dirichlet problem ... more We study the property of finite time vanishing of solutions of the homogeneous Dirichlet problem for the anisotropic parabolic equationsut−∑i=1nDi(ai(x,t,u)|Diu|pi(x,t)−2Diu)+c(x,t)|u|σ(x,t)−2u=f(x,t) with variable exponents of nonlinearity pi(x,t),σ(x,t)∈(1,∞). We show that the solutions of this problem may vanish in a finite time even if the equation combines the directions of slow and fast diffusion and estimate the extinction moment in terms of
Journal of Mathematical Analysis and Applications, 2009
ABSTRACT We study the dynamics and regularity of the level sets in solutions of the semilinear pa... more ABSTRACT We study the dynamics and regularity of the level sets in solutions of the semilinear parabolic equation where Ω⊂Rn is a ring-shaped domain, Δpu is the p-Laplace operator, a and μ are given positive constants, and H(⋅) is the Heaviside maximal monotone graph: H(s)=1 if s>0, H(0)=[0,1], H(s)=0 if s<0. The mathematical models of this type arise in climatology, the case p=3 was proposed and justified by P. Stone in 1972. We establish the conditions on the initial data which guarantee that the level sets are hypersurfaces, study the regularity of Γμ(t) and derive the differential equation that governs the dynamics of Γμ(t). The analysis is based on the introduction of a system of Lagrangian coordinates that transforms the moving surface Γμ(t) into a stationary one.
Nonlinear Analysis: Theory, Methods & Applications, 2014
Communications on Pure and Applied Analysis, 2012
The paper addresses the Dirichlet problem for the doubly nonlinear parabolic equation with nonsta... more The paper addresses the Dirichlet problem for the doubly nonlinear parabolic equation with nonstandard growth conditions: ut = div (a(x, t, u)|u|(x, t)|u|p(x, t)-2 with given variable exponents (x, t) and p(x, t). We establish conditions on the data which guarantee the comparison principle and uniqueness of bounded weak solutions in suitable function spaces of Orlicz-Sobolev type.
Page 1. Progress in Nonlinear Differential Equations and Their Applications SN Antontsev JI Dlaz ... more Page 1. Progress in Nonlinear Differential Equations and Their Applications SN Antontsev JI Dlaz S. Shmarev Energy Methods for Free Boundary Problems Applications to Nonlinear PDEs and Fluid Mechanics Birkhauser Page 2. Page 3. s On EU1U-ST6-E3R1 Page 4. ...
Page 1. Progress in Nonlinear Differential Equations and Their Applications SN Antontsev JI Dlaz ... more Page 1. Progress in Nonlinear Differential Equations and Their Applications SN Antontsev JI Dlaz S. Shmarev Energy Methods for Free Boundary Problems Applications to Nonlinear PDEs and Fluid Mechanics Birkhauser Page 2. Page 3. s On EU1U-ST6-E3R1 Page 4. ...
Differential Equations & Applications, 2012
Trends in Partial Differential Equations of Mathematical Physics, 2005
Elliptic and Parabolic Problems, 2002
Revista De La Real Academia De Ciencias Exactas Fisicas Y Naturales Serie a Matematicas, 2002
We study the properties of interfaces in solutions of the Cauchy problem for the nonlinear degene... more We study the properties of interfaces in solutions of the Cauchy problem for the nonlinear degenerate parabolic equation ut = ∆ u m − u p in R n × (0, T ] with the parameters m > 1, p > 0 satisfying the condition m + p ≥ 2. We show that the velocity of the interface
Evolution Equations and Lagrangian Coordinates, 1997
Evolution Equations and Lagrangian Coordinates, 1997
Siberian Mathematical Journal, 1991
Energy Methods in Continuum Mechanics, 1996
ABSTRACT
Let Ω ⊂ R n be a regular domain and Φ(s) ∈ C loc (R) be a given function. If M ⊂ L 2 (0, T ; W 1 ... more Let Ω ⊂ R n be a regular domain and Φ(s) ∈ C loc (R) be a given function. If M ⊂ L 2 (0, T ; W 1 2 (Ω)) ∩ L∞(Ω × (0, T)) is bounded and the set {∂tΦ(v)| v ∈ M} is bounded in L 2 (0, T ; W −1 2 (Ω)), then there is a sequence {v k } ∈ M such that v k v ∈ L 2 (0, T ; W 1 2 (Ω)), and v k → v, Φ(v k) → Φ(v) a.e. in Ω T = Ω × (0, T). This assertion is applied to prove solvability of the one-dimensional initial and boundary-value problem for a degenerate parabolic equation arising in the Buckley-Leverett model of two-phase filtration. We prove existence and uniqueness of a weak solution, establish the property of finite speed of propagation and construct a self-similar solution.
Evolution Equations and Lagrangian Coordinates, 1997
Evolution Equations and Lagrangian Coordinates, 1997
Proceedings of the Steklov Institute of Mathematics, 2008
We study the Dirichlet problem for a class of nonlinear parabolic equations with nonstandard anis... more We study the Dirichlet problem for a class of nonlinear parabolic equations with nonstandard anisotropic growth conditions that generalize the evolutional p(x, t)-Laplacian. We study the property of extinction of solutions in finite time. In particular, we show that the extinction may take place even in the borderline case when the equation becomes linear as t → ∞.
Proceedings of the Steklov Institute of Mathematics, 2010
ABSTRACT The aim of this paper is to establish sufficient conditions of the finite time blow-up i... more ABSTRACT The aim of this paper is to establish sufficient conditions of the finite time blow-up in solutions of the homogeneous Dirichlet problem for the anisotropic parabolic equations with variable nonlinearity $ u_t = \sum\nolimits_{i = 1}^n {D_i (a_i (x,t)|D_i u|^{p^i (x) - 2} D_i u) + \sum\nolimits_{i = 1}^K {b_i (x,t)|u|^{\sigma _i (x,t) - 2} u} } $ u_t = \sum\nolimits_{i = 1}^n {D_i (a_i (x,t)|D_i u|^{p^i (x) - 2} D_i u) + \sum\nolimits_{i = 1}^K {b_i (x,t)|u|^{\sigma _i (x,t) - 2} u} } . Two different cases are studied. In the first case a i ≡ a i (x), p i ≡ 2, σ i ≡ σ i (x, t), and b i (x, t) ≥ 0. We show that in this case every solution corresponding to a “large” initial function blows up in finite time if there exists at least one j for which min σ j (x, t) > 2 and either b j > 0, or b j (x, t) ≥ 0 and Σπ b j −ρ(t)(x, t) dx < ∞ with some σ(t) > 0 depending on σ j . In the case of the quasilinear equation with the exponents p i and σ i depending only on x, we show that the solutions may blow up if min σ i ≥ max p i , b i ≥ 0, and there exists at least one j for which min σ j > max p j and b j > 0. We extend these results to a semilinear equation with nonlocal forcing terms and quasilinear equations which combine the absorption (b i ≤ 0) and reaction terms.
Journal of Mathematical Analysis and Applications, 2010
We study the property of finite time vanishing of solutions of the homogeneous Dirichlet problem ... more We study the property of finite time vanishing of solutions of the homogeneous Dirichlet problem for the anisotropic parabolic equationsut−∑i=1nDi(ai(x,t,u)|Diu|pi(x,t)−2Diu)+c(x,t)|u|σ(x,t)−2u=f(x,t) with variable exponents of nonlinearity pi(x,t),σ(x,t)∈(1,∞). We show that the solutions of this problem may vanish in a finite time even if the equation combines the directions of slow and fast diffusion and estimate the extinction moment in terms of
Journal of Mathematical Analysis and Applications, 2009
ABSTRACT We study the dynamics and regularity of the level sets in solutions of the semilinear pa... more ABSTRACT We study the dynamics and regularity of the level sets in solutions of the semilinear parabolic equation where Ω⊂Rn is a ring-shaped domain, Δpu is the p-Laplace operator, a and μ are given positive constants, and H(⋅) is the Heaviside maximal monotone graph: H(s)=1 if s>0, H(0)=[0,1], H(s)=0 if s<0. The mathematical models of this type arise in climatology, the case p=3 was proposed and justified by P. Stone in 1972. We establish the conditions on the initial data which guarantee that the level sets are hypersurfaces, study the regularity of Γμ(t) and derive the differential equation that governs the dynamics of Γμ(t). The analysis is based on the introduction of a system of Lagrangian coordinates that transforms the moving surface Γμ(t) into a stationary one.
Nonlinear Analysis: Theory, Methods & Applications, 2014
Communications on Pure and Applied Analysis, 2012
The paper addresses the Dirichlet problem for the doubly nonlinear parabolic equation with nonsta... more The paper addresses the Dirichlet problem for the doubly nonlinear parabolic equation with nonstandard growth conditions: ut = div (a(x, t, u)|u|(x, t)|u|p(x, t)-2 with given variable exponents (x, t) and p(x, t). We establish conditions on the data which guarantee the comparison principle and uniqueness of bounded weak solutions in suitable function spaces of Orlicz-Sobolev type.
Page 1. Progress in Nonlinear Differential Equations and Their Applications SN Antontsev JI Dlaz ... more Page 1. Progress in Nonlinear Differential Equations and Their Applications SN Antontsev JI Dlaz S. Shmarev Energy Methods for Free Boundary Problems Applications to Nonlinear PDEs and Fluid Mechanics Birkhauser Page 2. Page 3. s On EU1U-ST6-E3R1 Page 4. ...
Page 1. Progress in Nonlinear Differential Equations and Their Applications SN Antontsev JI Dlaz ... more Page 1. Progress in Nonlinear Differential Equations and Their Applications SN Antontsev JI Dlaz S. Shmarev Energy Methods for Free Boundary Problems Applications to Nonlinear PDEs and Fluid Mechanics Birkhauser Page 2. Page 3. s On EU1U-ST6-E3R1 Page 4. ...
Differential Equations & Applications, 2012
Trends in Partial Differential Equations of Mathematical Physics, 2005
Elliptic and Parabolic Problems, 2002
Revista De La Real Academia De Ciencias Exactas Fisicas Y Naturales Serie a Matematicas, 2002
We study the properties of interfaces in solutions of the Cauchy problem for the nonlinear degene... more We study the properties of interfaces in solutions of the Cauchy problem for the nonlinear degenerate parabolic equation ut = ∆ u m − u p in R n × (0, T ] with the parameters m > 1, p > 0 satisfying the condition m + p ≥ 2. We show that the velocity of the interface