2.1. Mathematical Description of the Model
Let
be a bounded domain with boundary
; without loss of generality, assume the origin 0 belongs to
. Suppose
is an arbitrarily given point, while
denotes the arc, oriented in the usual manner, joining the origin 0 to the point
along the boundary of
D. For more details, one can refer to Ciarlet [
3]. The governing equation of simplified Von Karman plate without rotational inertia is:
with the clamped boundary
where
U is transversal displacement of the plate.
is Von Karman bracket [
26] (also known as Monge-Ampère form [
3]) with the form of
is the Airy function satisfies
in which the physical parameter
can refer to [
1].
is defined as
and
where
are components of the in-plane force on boundary along the direction
, which comply with
where
are membrane forces in the plate; for more details, one can refer to [
3]. Moreover, let
,
be the solution of the following system
Thus, Equation (
1) can be rewritten as:
In some cases, only
is named Airy function, while
is called the in-plane force, (see Chueshov and Lasiecka [
26]). This convention is employed in this paper.
To formulate the system tackled in this paper, some spaces are introduced in the following. Let
,
,
,
, where
,
,
are the usual Sobolev Spaces. Let
, then
A is self-adjoint, positive, unbounded linear operators and
is compact. Therefore, their eigenvalues
satisfy
and the corresponding eigenvalues
forms an orthonormal basis in
. Then, we can interpret the power of
by the method developed by Temam [
55]. Specifically,
, however, it is mentioned here that
. Nevertheless, it is emphasized here that
with the boundary in Equation (
2). In fact, the operator
with the boundary condition in Equation (
2) is a self-adjoint, positive, unbounded linear operators from
to
and
is compact. Thus, the power of
can be defined; furthermore,
.
Suppose
P is a stochastic pressure signified by white noise, then the dynamics equation of abstract dimensionless clamped simplified Von Karman plate without rotational inertia driven by white noise are as follow
with the clamped boundary condition
where
is the dimensionless transversal displacement of the plate.
are a given constant,
W is the one dimensional two-sided real-valued standard Wiener process, and is called white noise. is the coefficient of damping.
Equation (
10a) describes abstract dimensionless clamped simplified Von Karman plate without rotational inertia driven by additive/multiplicative white noise, respectively. Furthermore,
satisfies
and
is in agreement with
where
are derived from Equations (
3) and (
4). By the monograph of Lions and Magenes [
57],
, define
The system described by Equations (
10a), (
10c), and (
10e)–(
10h) is denoted by SAVKP. The system interpreted by Equations (
10b), (
10c), and (
10e)–(
10h) is represented by SMVKP.
Invoking the compactness of
A, the Hilbert space
with norm
and
can be defined as the mechanism in Temam [
55], especially,
. Moreover, for all
,
can be compact imbedding in
and the following holds
Let equipped with Graph norm and the induced inner product, then they are all Hilbert spaces.
Let
be a separable space with Borel
algebra
and
be a probability space.
is a family of measure preserving transformations such that
is measurable,
for all
. Then, the flow
together with the probability space
is called a metric dynamical system. For the particular applications in this paper, the metric dynamical systems generated by a one dimensional two-sided standard Wiener process defined on a Probability space
is introduced there. Let
,
is the
algebra induced by the compact open topology for this set and
is the Wiener measure on
. Set
according to Arnold [
4], we have
is ergodic with respect to the flow
. Thus,
is the metric dynamical systems employed in this paper. Moreover, the Ornstein–Uhlenbeck process, which should be used in transforming a stochastic system to a random system, is introduced as follows
in which
. The general form for the solution of Equation (
13) is
Let
where
is defined by Equation (
12) in
Section 2. Merging with integration by parts,
is the solution for the system in Equation (
13).
Although by no means always, it will be convenient to reduce Equations (
10a) and (
10b) to an evolution equation of the first order in time in the following manner. Let
, then Equation (
10a) can be transformed to the ensuing form
where
and
The system described by Equations (
10c), (
15) and (
10e)–(
10h) denoted by SAVKPT1. Obviously, SAVKP is equivalent to SAVKPT1.
To accomplish the stabilization estimation for the solution of SAVKPT1, the following systems is needed. Suppose
are two solution of SAVKPT1, then
where
.
Furthermore, let
and
thus
where
here
Equation (
18) is a partial differential equations with random coefficient which can be studied
by
. Let SAVKPT2 signify the system described by Equations (
18), (
10c) and (
10e)–(
10h). It is emphasized that SAVKPT2 is not equivalent to SAVKPT1.
Analogously, let
and
define
, the following system associated with SMVKP can be attained.
in which
and
where
SMVKPT1 represents the systems defined by Equations (
20), (
10c) and (
10e)–(
10f), then SMVKP and SMVKPT1 are equivalent. The system described by Equations (
21), (
10c) and (
10e)–(
10f) is denoted by SMVKPT2.
Furthermore, assume
are two solutions of SAVKPT2, thus
in which
Equation (
22) is used to obtain the stabilization estimation for SMVKPT1.
Remark 1. For the sake of brevity, when no ambiguity is possible, the symbols used in SAVKPT and SMVKPT, SAVKPT1 and SMVKPT1, and SAVKPT2 and SMVKPT2 are the same or similar. Since each of the symbols has a clearl explanation, it is not confusing to express the main results in this paper. However, it must be kept in mind that they are not the same.
2.2. Main Results
Approved by the equivalent between SAVKPT and SAVKPT1, and SMVKPT and SMVKPT1, it is enough to only address the dynamical behavior of SAVKPT1 and SMVKPT1. This subsection is used to present the main results of this paper. Let
2.2.1. Random Attractors in Additive White Noise Case
This part is devoted to providing the main results for SAVKPT1. The following Theorem considers the existence and uniqueness of solution for SAVKPT2.
Theorem 1. For any given initial value , there exists a uniqueness (mild) solution for SAVKPT2
Furthermore, let , which means that is the solution mapping of SAVKPT2. Then, Let
by means of Theorem 1,
is the RDS induced by SAVKPT2. Correspondingly, SAVKPT1 can also generate a RDS
which is defined as
here
is defined by Equation (
17). Furthermore, the solution mapping determined by SAVKPT1 is denoted by
, then
The following turns to the existence of global random attractors for SAVKPT1.
Let
be any given positive constant,
and
in which
are constants that satisfy Equation (
45) in
Section 3.2.1.
The next theorem considers the existence and expectation of radius of global random attractors for .
Theorem 2. possesses the global random attractors in which satisfies -a.s.where denotes the open ball centered at the origin with radius is , while M is given by Equation (A24) in Section 3.2.1. 2.2.2. Random Attractors in Multiplicative White Noise Case
The main results for SMVKPT1 is given in this part.
The form of following theorem is very similar to the Theorem 1.
Theorem 3. For any given initial value , SMVKPT2 possesses uniqueness (mild) solution .
Furthermore, set , which indicates that is the solution mapping of SMVKPT2. Thus, Therefore, set
then,
the RDS induced by SMVKPT2 and RDS
defined as follow
is the RDS generate by SMVKPT1, where
is defined by Equation (
19). In additive, let
Thus, is the solution mapping of SMVKPT1.
The following turns to the existence of global random attractors for SMVKPT1.
Suppose
is any given positive constant,
and
Set
where
are constants satisfying Equation (
45) in
Section 3.2.2. Then, the existence and finite expectation of radius of global random attractors for
can be asserted by the next theorem.
Theorem 4. There exists global random attractors for in ; moreover,where denotes the open ball centered at the origin with radius is , while M is given by Equation (A43) in Section 3.2.2. Comparing Theorems 1 and 3, as well as Theorems 2 and 4, their forms are the same or similar, while there exists essential difference between them, which is expounded in
Section 5.
2.2.3. Global Dynamics in Both Additive and Multiplicative White Noise Cases
Based on the theoretical results and the relationship between invariant measures and global attractors introduced in Proposition 2 in
Section 3.1, the rest of this subsection is dedicated to studying the global dynamics of the stochastic Von Kaman plates, which is accomplished by deriving the components of global random attractor numerically, the main components are referred as global random point attractor and global random basic attractor. The modal equations associated with the stochastic Von Karman plates which are not display here (see Equation (A1) in
Appendix A) can be obtained by employing inertial manifold with delay [
58] and nonlinear gakerlin method [
59].
Let
,
in
Appendix A,
Figure 1 shows the model for vibration of Von Karman plate. The eigenvalues
and eigenvectors
of operator
A and integration with respect to space variable in Equation (A2) listed in
Appendix A can be performed by COMSOL with Matlab [
60], and then the solution of model equations can be obtained by stochastic Runge–Kutta method [
61].
The situation of additive white noise. In this case, the
P in
Figure 1 is equal to
, let
,
,
and
are component of the in-plane force on boundary along the direction
, thus the
in Equation (10h) can be derived by Equations (
3) and (
4). Since
D is rectangle,
. Furthermore, let
, the dynamics of simplified Von Karman plate without rotational inertia driven by additive white noise is signified by the motion of the position
of the plate, which are studied in the following cases.
Case I. Let
,
; the global random basic attractor, global random point attractor and global random attractors for SAVKP are the same.
Figure 2 shows that global random basic attractor is a random fixed point which supports a invariant Markov measure
. Furthermore,
is almost surely global stability.
Case II. Set
, in this situation, global random basic attractor is equivalent to global random point attractor. Global random basic attractor (see
Figure 3c) and its section (see
Figure 3a) indicate that the system possesses two invariant Markov measures
which are supported by two fixed random points.
Figure 3b illustrates the section of the global random attractor of SAVKP.
Case III. let
,
,
Figure 4 describes the invariant measures and random attractors for SAVKP. Global random basic attractor is equivalent to global random point attractor in this status. Section of global random basic attractor demonstrated by
Figure 4a reveals that the steady states of the system comprise four parts, which means that are least four stable invariant Markov measures for SAVKP exist. In addition, in
Figure 4a, it can be obtained that the local dynamics of the system may be complex. The sketch of global random basic attractor is shown by
Figure 4b,
Case IV. when
,
, global random basic attractor is also equivalent to global random point attractor in this case. The numerical results on the invariant measures and random attractors for SAVKP (see
Figure 5) expose the system has a almost surely global stability invariant Markov measure supported by a random fixed points.
The situation of multiplicative white noise. In this case, the
P in
Figure 1 is equal to
, while the remaining parameters are chosen to be the same as in the situation of additive white noise. The the dynamics of SMVKP are studied in the following cases.
Case I. Let
,
, similar to the Case I in additive noise, global random basic attractor, global random point attractor and global random attractors for SAVKP are the same in this circumstance. The assertion that there exists an almost surely global stability invariant measure supported by a random fixed points for SMVKP can be attained by
Figure 6.
Case II. When
,
, the numerical results on invariant measures and random attractors were described by
Figure 7. Invoking the section of global random basic attractor (see
Figure 7a), it can be obtained that the system possesses two local stable invariant Markov measures, which together with the numerical results of section global random point attractor described by
Figure 7b give that another invariant measure exists, which could even be a unstable invariant Markov measure.
Case III. Set
,
,
Figure 8 expresses the numerical results on global random attractors for SMVKP. The section of global random basic attractor shown by
Figure 8a indicates that there exist four local stable invariant Markov measures. Furthermore, SMVKP has another three invariant measures which are interpreted by section of global random point attractor (see
Figure 8b). The sketch of global random point attractor is illustrated by
Figure 8c.
Case IV. Let , , the similar results in Case IV can be got, the Figure to describe the invariant measure and random attractor is not displayed here.
Some affirmations can be approved by the aforementioned numerical results. For the clamped irrotational inertia Von Karman driven by additive white noise, fixed , let vary from to , the global -bifurcation occurs in the motion of the system. Change the value of to be a big one, such , the dynamical behavior becomes much more interesting. From the view of global dynamics, there exits secondary -bifurcation. The local dynamics of the system is complex. On the other hand, let and change the from to 2, the phenomenon of global -bifurcation disappears. As for clamped irrotational inertia Von Karman driven by multiplicative white noise, fixed , the similar global dynamics of the system can be obtained with varying the from to . In addition, once the coefficient of the multiplicative white noise becomes big, global -bifurcation vanishes. Nevertheless, there exist differences between the two cases above. The multiplicative white noise is more likely to result in the appearance of global -bifurcation and secondary global -bifurcation in the motion of clamped Von Karman without rotational inertia than additive noises. when the secondary -bifurcation occurs, the local dynamics of the system driven by additive white noise is more complex than the situation of multiplicative white noise.