ОN INVERSE PROBLEM OF DETERMINING THE ABSORPTION COEFFICIENT IN THE PARABOLIC EQUATION UNDER THE CONDITION OF FINAL OBSERVATION
https://doi.org/10.26583/vestnik.2024.5.5
EDN: NGQCYO
Abstract
We consider the nonlinear inverse problem of determining the $x$-dependent lower coefficient in a uniformly parabolic equation with many spatial variables. The coefficients of the equation can depend on both the time and spatial variables and are assumed to be bounded, but generally speaking, discontinuous. However (in contrast to the papers of other authors), there are no restrictions on the signs of the lower coefficients of the equation and its right-hand side. As an additional condition, we put the condition of the final (at the final moment of time) observation. The solution of the inverse problem is understood in a generalized sense and is sought in Sobolev classes. We establish two types of sufficient conditions under which a generalized solution of the inverse problem exists and is unique. We also give the example of the inverse problem for which the results proved in the work are valid. It is noted that the solution of the specified problem exists and is unique either if the time interval on which the problem is considered is sufficiently large (and the domain of spatial variables is fixed) or if the domain of spatial variables is sufficiently small (and the time period is fixed).
Keywords
References
1. Prilepko A.I., Solov’ev V.V. O razreshimosti obratnyh kraevyh zadach opredeleniyakoefficienta pered mladshei proizvodnoi v parabolicheskom uravne-nii [On the solvability ofinverse boundary value prob-lems of determining the coefficient before the lowest derivative in aparabolic equation]. Differentsial’nye uravneniya. 1987. Vol. 23. No. 1. Pp. 136–143 (in Rus-sian).
2. Isakov V. Inverse parabolic problems with the final overdetermination. CommunicationsPure and Applied Mathemat Ics. 1991. Vol. 44. Pp. 185–209.
3. Prilepko A.I., Tikhonov I.V. Princip positivnosti v lineinoi obratnoi zadache i egopriminenie k koeffi-cientnoi zadache teploprovodnosti [The principle of positivity of the solutionin the linear inverse problem and its application to the coefficient problem of heat conduction]. Doklady RAN, 1999. Vol. 364. No. 1. Pp. 21‒23 (in Russian).
4. Prilepko A.I., Kostin A.B. O nekotoryh obratnyh zadachah dlya parabolicheskih uravne-nii s final’nym i integral’nym nablyudeniem [On some inverse problems for parabolic equationswith final and integral observa-tion]. Matematicheskii sbornik, 1992. Vol. 183. No. 4. Pp. 49‒68 (in Russian).
5. Prilepko A.I., Kostin A.B. Ob obratnyh zadachah opredeleniya koeffcienta v paraboliches-kom uravnenii. I. [On inverse problems of determining the coefficient in a parabolic equation. I]. Sibirskii matematicheskii zhur-nal, 1992. Vol. 33. No. 3. Pp. 146‒155 (in Russian).
6. Prilepko A I., Kostin A.B. Ob obratnyh zadachah opredeleniya koeffcienta v paraboliches-kom uravnenii. II. [On inverse problems of determining the coefficient in a parabolic equation.II]. Sibirskii matematicheskii zhurnal, 1992. Vol. 34. No. 5. Pp. 147‒162 (in Russian).
7. Kostin A.B. Obratnaya zadacha opredeleniya koefficienta pri u v parabolicheskom uravne-nii po usloviyu nelokal’nogo nablyudeniya. [Inverse problem of determining the coefficientbeforeuin a parabolic equation under the condition of non-local observation]. Differentsial’nyeuravneniya, 2015. Vol. 51. No. 5. Pp. 596–610 (in Russian).
8. Kamynin V.L. Ob odnoznachnoi razreshimosti obratnoi zadachi dlya parabolicheskihuravnenii s usloviem final’nogo pereopredeleniya. [On the unique solvability of the inverseproblem for parabolic equa-tions with the condition of final overdetermination]. Matematicheskie zametki, 2003. Vol. 79. No. 2. Pp. 217–227 (in Russian).
9. Ladyzhenskaya O.A., Solonnikov V.A., Ural’tseva N.N. Lineinye i kvazilineinye uravne-niya parabolich-eskogo tipa. [Linear and quasilinear parabolic equations of parabolic type]. Moscow, Nauka Publ. 1967. 736 p. (in Russian).
10. Gilbarg D., Trudinger N. Ellpiticheskie differen-cial’nye uravneniya s chastnymi proizvodnymi vtorogo poryadka. [Elliptic partial differential equations of sec-ond order]. Moscow, Nauka Publ., 1989. 464 p. (in Rus-sian).
11. Arena O. Sopra una classe di equazioni paraboli-che. Bolletino Unione Matematica Italiana (4), 1969. Vol. 2, No. 1. Pp. 9–24.
12. Krylov N.V. Nelineinye ellipticheskie i paraboli-cheskie uravneniya vtorogo poryadka [Nonlinear sec-ond order elliptic and parabolic equations]. Moscow, Nauka Publ., 1985. 376 p. (in Russian).
13. Friedman A. Uravneniya s chastnymi proisvod-nymi parabolicheskogo tipa. [Partial differential equa-tions of parabolic type]. Moscow Mir Publ., 1968. 428 p. (in Russian).
14. Ladyzhenskaya O.A. Matematicheskie voprosy dinamiki vyazkoi neszhimaemoi zhidkosti [Mathemati-cal problems in the dynamics of a viscous incompressi-ble fluid] Moscow, Nauka Publ, 1970. 288 p. (in Rus-sian).
15. Lyusternik L.A., Sobolev V.I. Kratkii kurs funkcional’nogo analisa. [Brief course of functional analysis]. Moscow Vysshaya shkola Publ., 1982, 270 p. (in Russian)
Review
For citations:
Kamynin V.L. ОN INVERSE PROBLEM OF DETERMINING THE ABSORPTION COEFFICIENT IN THE PARABOLIC EQUATION UNDER THE CONDITION OF FINAL OBSERVATION. Vestnik natsional'nogo issledovatel'skogo yadernogo universiteta "MIFI". 2024;13(5):329-339. (In Russ.) https://doi.org/10.26583/vestnik.2024.5.5. EDN: NGQCYO