| Title:
             | 
Unique solvability of a linear problem with perturbed periodic boundary values (English) | 
| Author:
             | 
Mehri, Bahman | 
| Author:
             | 
Nojumi, Mohammad H. | 
| Language:
             | 
English | 
| Journal:
             | 
Czechoslovak Mathematical Journal | 
| ISSN:
             | 
0011-4642 (print) | 
| ISSN:
             | 
1572-9141 (online) | 
| Volume:
             | 
49 | 
| Issue:
             | 
2 | 
| Year:
             | 
1999 | 
| Pages:
             | 
351-362 | 
| Summary lang:
             | 
English | 
| . | 
| Category:
             | 
math | 
| . | 
| Summary:
             | 
We investigate the problem with perturbed periodic boundary values \[ \left\rbrace \begin{array}{ll}y^{\prime \prime \prime }(x) + a_2(x) y^{\prime \prime }(x) + a_1(x) y^{\prime }(x) + a_0(x) y(x) = f(x) , y^{(i)}(T) = c y^{(i)}(0), \ i = 0, 1, 2; \ 0 < c < 1 \end{array}\right.\] with $a_2, a_1, a_0 \in C[0,T]$ for some arbitrary positive real number $T$, by transforming the problem into an integral equation with the aid of a piecewise polynomial and utilizing the Fredholm alternative theorem to obtain a condition on the uniform norms of the coefficients $a_2$, $a_1$ and $a_0$ which guarantees unique solvability of the problem. Besides having theoretical value, this problem has also important applications since decay is a phenomenon that all physical signals and quantities (amplitude, velocity, acceleration, curvature, etc.) experience. (English) | 
| Keyword:
             | 
Ordinary differential equations | 
| Keyword:
             | 
integral equations | 
| Keyword:
             | 
periodic boundary value problems | 
| MSC:
             | 
34B05 | 
| MSC:
             | 
34B15 | 
| MSC:
             | 
34C10 | 
| MSC:
             | 
45B05 | 
| idZBL:
             | 
Zbl 0955.34007 | 
| idMR:
             | 
MR1692528 | 
| . | 
| Date available:
             | 
2009-09-24T10:23:16Z | 
| Last updated:
             | 
2020-07-03 | 
| Stable URL:
             | 
http://hdl.handle.net/10338.dmlcz/127493 | 
| . | 
| Reference:
             | 
[1] H. Brezis: Analyse Fonctionnelle, Théorie et Applications.Masson, Paris, 1983. Zbl 0511.46001, MR 0697382 | 
| Reference:
             | 
[2] R. Brown: A Topological Introduction to Nonlinear Analysis.Birkhäuser, Boston, 1993. Zbl 0794.47034, MR 1232418 | 
| Reference:
             | 
[3] J. A. Cochran: Analysis of Linear Integral Equations.McGraw Hill, New York, 1972. Zbl 0233.45002, MR 0447991 | 
| Reference:
             | 
[4] R. Kress: Linear Integral Equations.Springer-Verlag, New York, 1989. Zbl 0671.45001, MR 1007594 | 
| Reference:
             | 
[5] M. Reed, and B. Simon: Methods of Modern Mathematical Physics, Vol. 1: Functional Analysis.Academic Press, Orlando, Florida, 1980. MR 0751959 | 
| . |