September 27, 2004 16:46 WSPC/Book Trim Size for 9.75in x 6.5in GlobalAttractors/chapter 0
viii Global Attractors of Non-autonomous Dissipative Dynamical Systems
of dissipative systems, that is, conditions relating to the character of behaviour
of solution of the system when assuming its dissipativity, for different classes of
differential equations. Among them are the works of V. M. Gershtein
[
159
]
-
[
163
]
,
V. V. Zhikov
[
331
]
-
[
332
]
, I. L. Zinchenko
[
334
]
, M. A. Krasnoselsky
[
159
]
, S. Yu.
Pilyugin
[
269
]
, V. A. Pliss
[
270
]
-
[
271
]
, M. L. Cartwright and J. E. Littlewood
[
44
]
-
[
46
]
, N. Levinson
[
237
]
, G. Fusco and M. Oliva
[
157
]
, J. Skowronski and S. Ziemba
[
307
]
and other authors.
For a compact map on a Banach space, V. M. Gerstein
[
162
]
, V. M. Ger-
stein and M. A. Krasnoselskii
[
159
]
investigated the existence of maximal com-
pact invariant set and studied some of its properties. In works of G. Billoti,
G. Cooperman, J. LaSalle, O. Lopes, P. Massat, M. Slemrod, J. Hale
[
175, 26,
124
]
,
[
171
]
-
[
176
]
,
[
235
]
,
[
246
]
-
[
248
]
and a lot of other authors many important results
obtained for ordinary differential equations
[
270
]
-
[
271
]
are generalized to functional-
differential equations.
Of late in the theory of partial differential equations there appeared works of
A. V. Babin and M. I. Vishik
[
12
]
-
[
16
]
, Ju. S. Ilyashenko
[
194
]
-
[
197
]
, O. A. La-
dyzhenskaya
[
230
]
, A. N. Sharkovsky
[
296
]
, R. Temam
[
314
]
and other authors,
in which, are studied evolutionary equations with maximal attractors (dissipative
evolutionary equations).
We note that all works mentioned above (with rare exceptions) studied periodical
or autonomous systems. These results are presented in monographs
[
175
]
,
[
270
]
-
[
272
]
,
[
296
]
.
If the right hand side f of the equation (0.1) is non-periodic, e.g. quasi-periodic
(almost periodic by Bohr, recurrent in sense the of Birkhoff, almost periodic by
Levitan, stable by Poisson) or depending on time in more complicated way, then
the situation essentially complicates already in the class of almost periodic systems.
It is caused at least by two reasons.
First, the definition of dissipativity in the non-autonomous case needs to be made
more precise because Levinson’s definition in the class of non-periodical systems
divides on some non equivalent notions and we need to choose one which allows
us develop a general theory which would contain as particular case most essential
results obtained for periodical dissipative systems.
Second, in the study of periodic dissipative systems an important role is played
by discrete dynamical system (cascade) generated by degrees of Poincar´e’s trans-
formation (mapping). For non-periodic systems there is no Poincar´e’s transforma-
tion and, consequently, the approach created for research on periodical dissipative
systems is not useful in the more general case. That is why to study non-periodical
dissipative systems we need new ideas; that is, making a theory of non-autonomous
dissipative dynamical systems demands making corresponding methods of research.
Our approach to the study of dissipative systems of differential equations consists
of drawing to the study of non-autonomous dissipative systems ideas and methods