In this paper, we introduce a class of neutral-type neural networks with delay in the leakage terms. Using coincidence degree theory, Lyapunov functional method and the properties of neutral operator, we establish some new sufficient criteria for the existence and global attractiveness of periodic solutions. Finally, an example demonstrates our findings.
Citation: Shihong Zhu, Bo Du. Global attractive periodic solutions of neutral-type neural networks with delays in the leakage terms[J]. AIMS Mathematics, 2023, 8(11): 26731-26744. doi: 10.3934/math.20231368
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In this paper, we introduce a class of neutral-type neural networks with delay in the leakage terms. Using coincidence degree theory, Lyapunov functional method and the properties of neutral operator, we establish some new sufficient criteria for the existence and global attractiveness of periodic solutions. Finally, an example demonstrates our findings.
The study of differential equations and variational problems with nonstandard p(x)−growth conditions is a new and interesting topic. It arises from nonlinear elasticity theory, electrorheological fluids, etc. (see [1,2,3,4,5,6,7,8,9]).
In this paper, we consider the Neumann problem to the following initial parabolic equation with logarithmic source:
{ut−div(|∇u|p−2∇u)=|u|p−2ulog|u|−∮Ω|u|p−2ulog|u|dx,x∈Ω,t>0,∂u(x,t)∂η=0,x∈∂Ω,t>0,u(x,0)=u0,x∈Ω,t>0, | (1.1) |
where Ω is a bounded domain in RN with smooth boundary ∂Ω, p ∈ (2,+∞), ∮Ωu0dx=1|Ω|∫Ωu0dx=0 with u0≠0.
Problem (1.1) has been studied by many other authors in a more general form
{ut−Δu=f(u)−∮Ωf(u)dx,x∈Ω,t>0,∂u(x,t)∂η=0,x∈∂Ω,t>0,u(x,0)=u0,x∈Ω,t>0, | (1.2) |
where Ω is a bounded domain in RN (N≥1) with |Ω| denoting its Lebesgue measure, N is the outer normal vector of ∂Ω, and the function f(u) is usually taken to be a power of u.
Wang. M, Wang, .Y in [10], studied the properties of positive solutions when f(u)=|u|p. The authors showed global existence and exponential decay in the case where |Ω| ≤k and they obtained a blow-up result under the assumption that the initial data is bigger than some "Gaussian function" in the case where |Ω| >k.. When f(u)=u|u|p and ∫Ωudx>0, non-global existence result is discussed by [11].
C. Qu, X. Bai, S. Zheng [12] considered the nonlocal p-Laplace equation
{ut−div(|∇u|p−2∇u)=uq−∮Ωuqdx,x∈Ω,t>0,∂u(x,t)∂η=0,x∈∂Ω,t>0,u(x,0)=u0,x∈Ω,t>0, | (1.3) |
where a critical blow-up solution is determined by q and the sign of the initial energy.
More recently, L. Yan, Z. Yong [13] established a blow-up and non-extinction of solutions under appropriate conditions for (1.1) in the case p=2.
Apart the aforesaid attention given to polynomial nonlinear terms, logarithmic nonlinearity has also received a great deal of interest from both physicists and mathematicians (see for example [14,15,16,17,18]). This type of nonlinearity was introduced in the nonrelativistic wave equations describing spinning particles moving in an external electromagnetic field and also in the relativistic wave equation for spinless particles [19]. Moreover, the logarithmic nonlinearity appears in several branches of physics such as inflationary cosmology [20], nuclear physics [21], optics [22] and geophysics [23]. With all those specific underlying meaning in physics, the global-in-time well-posedness of solution to the problem of evolution equation with such logarithmic type nonlinearity captures lots of attention. Birula and Mycielski ([24,25]) studied the following problem:
{utt−uxx+u−εuln|u|2=0 in [a,b]×(0,T),u(a,t)=u(b,t)=0,(0,T),u(x,0)=u0(x), ut(x,0)=u1(x) in [a,b], | (1.4) |
which is a relativistic version of logarithmic quantum mechanics and can also be obtained by taking the limit p goes to 1 for the p -adic string equation ([26]). In [27], Cazenave and Haraux considered
utt−Δu=uln|u|k in R3 | (1.5) |
and established the existence and uniqueness of the solution for the Cauchy problem. Gorka [28] used some compactness arguments and obtained the global existence of weak solutions, for all
(u0,u1)∈H10(Ω)×L2([a,b]), |
to the initial-boundary value problem (1.4) in the one-dimensional case. Bartkowski and Gorka, [29] proved the existence of classical solutions and investigated the weak solutions for the corresponding one-dimensional Cauchy problem for Equation (1.5). Hiramatsu et al. [30] introduced the following equation
utt−Δu+u+ut+|u|2u=uln|u| | (1.6) |
to study the dynamics of Q-ball in theoretical physics and presented a numerical study. However, there was no theoretical analysis for the problem. In [31], Han proved the global existence of weak solutions, for all
(u0,u1)∈H10(Ω)×L2(Ω), | (1.7) |
to the initial boundary value problem (1.6) in R3.
Motivated by the above studies, in this paper we investigate a blow up, non existence and decay of solutions of problem (1.1).
It is necessary to note that the presence of the logarithmic nonlinearity causes some difficulties in deploying the potential well method. In order to handle this situation we need the following logarithmic Sobolev inequality which was introduced in [10].
Lemma 1. Let p>1,μ>0, and u∈W1,p(Rn)╲{0}. Then we have
p∫Rn|u(x)|plog(|u(x)|‖u(x)‖Lp(Rn))dx+nplog(pμenLp)∫Rn|u(x)|pdx≤μ∫Rn|∇u(x)|pdx, |
where
Lp=pn(p−1e)p−1π−p2[Γ(n2+1)Γ(np−1p+1)]pn. |
We begin this section by introducing some notations that will be used throughout the paper
‖u‖p=‖u‖LP(Ω),‖u‖1,Ω=‖u‖W1,p0=‖∇u‖p, |
for 1<p<+∞.We also we define X0=W1,p0(Ω)╲{0}.
Lemma 2. Let ϱ be a positive number. Then the following inequality holds
logs≤e−1ϱsϱ,for alls∈[1,+∞]. |
Lemma 3. (a) For any function u∈W1,p0(Ω), we have the inequality
‖u‖q≤Bq,p‖∇u‖p, |
for all q∈[1,∞) if n≤p, and 1≤q≤npn−p if n>p. Then the best constant depends Bq,p only on Ω,n,p and q.
We will denote the constant Bp,p by Bp.
(b) Let 2≤p<q<p∗. For any u∈W1,p0(Ω) we have
‖u‖q≤C‖∇u‖αp‖u‖1−αp, |
where C is a positive constant and
α=(1p−1q)(1n−1p+1p)−1. |
Remark 1. It follows from Lemma 2 that
splogs≤e−1ϱsp+ϱ,forallϱ>0ands∈[1,+∞). |
Now we considering the functional J and I defined on X0 as follows
J(u)=1p‖∇u‖pp−1p∫Ω|u|pln|u|dx+1p2‖u‖pp. | (2.1) |
I(u)=‖∇u‖pp−∫Ω|u|pln|u|dx. | (2.2) |
The functions I and J are continuous (they are defined as in [32] with some modifications). Moreover, we have
J(u)=1pI(u)+1p2‖u‖pp. | (2.3) |
Then it is obvious that
ϕ={u∈X0:I(u)=0, ‖u‖pp≠0}.
d=infu∈ϕJ(u).
M=Rpp2.
From [33], we know d≥M.
Nδ={u∈X0:Iδ(u)=0}.
Theorem 1. (Local existence) Let u0∈X0. Then there exists a positive constant T0 such that the problem (1.1) has a weak solution u(x,t) on Ω× (0,T0). Furthermore, u(x,t) satisfies the energy inequality
∫t0‖us(s)‖22ds+J(u(t))≤J(u0),∀t∈[t,T0). | (2.4) |
Lemma 4. Suppose that θ>0, α>0, β>0 and h(t) is a nonnegative and absolutely continuous function satisfying h′(t)+αhθ(t)≥β, then for 0<t<∞, it holds
h(t)≥min{h(0),(βα)1θ}. |
Lemma 5. If 0<J(u0)<E1=1p2ebp, where b=nlog(p2enLp),, then there exists a positive constant α2>α1 such that
‖u‖p≥α2. | (2.5) |
Proof. Using the logarithmic Sobolev inequality in Lemma 1 and μ=p, we have
J(u)=1p‖∇u‖p−1p∫Ω|u|plog|u|dx+1p2‖u‖pp≥[np3log(p2enLp)−1plog‖u‖p+1p2]‖u‖pp, | (2.6) |
Denote α=‖u‖p, b=nlog(p2enLp), we have
h(α)=[bp3−1plnα+1p2]αp. | (2.7) |
Let h′(α1)=0, E1= h(α1)=1p2ebp2
h′(α1)=0⇒[bp3αp1−1pαp1logα+αp11p2]′=0⇒bp2−logα1=0⇒α1=ebp2. |
Furthermore, we get h(α) is increasing in (0,α1) and decreasing in (α1,∞). Since J(u0)<E1, there exists a positive constant α2>α1 such that J(u0) = h(α2). Let α0 =‖u0‖2, from (2.6) and (2.7), we have
h(α0)≤J(u0). |
Since α0, α2 ≥α1, we get α0≥α2, so (2.5) holds for t=0.
To prove (2.5) for t>0, we assume the contrary that ‖u(.,t)‖2< α2 for some t0>0. By the continuity of ‖u(.,t)‖2 and α1<α2, we may choose t0 such that ‖u(.,t0)‖2 > α1, then it follows from (2.6)
J(u0)=h(α2)<h(‖u(.,t0)‖2)≤J(u)(t0), |
which contradicts the fact that J(u) is nonincreasing in t by (2.4), so (2.5) is true.
Lemma 6. Let H(u)=E1−J(u),J(u0)<E1, then H(u) satisfies the following estimates
0<H(u0)≤H(u). |
Proof. It is obvious that H(u)is nondecreasing in t, by (2.4), then it follows from J(u0)<E1that
H(u)≥H(u0)=E1−J(u0)>0. |
Let u∈X0 and consider the real function j :λ→ J(λu) for λ>0,
The following Lemma shows that j(λ) has a unique positive critical point λ∗=λ∗(u) see [3].
Lemma 7. Let u∈X0.Then it holds
(1) limj(λ)λ→0+=0 and limj(λ)λ→+∞=−∞,
(2) there is a unique λ∗=λ∗(u)>0 such that j′(λ∗)=0,
(3) j(λ) is increasing on (0,λ∗), decreasing on (λ∗,+∞) and attains the maximum at λ∗,
(4) I(λu)>0 for 0<λ<λ∗, I(λu)<0 for λ∗<λ<+∞ and I(λ∗u)=0.
Proof. For u∈X0, by the definition of j, It is clear that (1) holds due to ‖u‖p≠0, and by derivation of j, we have
ddλj(λ)=λp−1∫Ω[|∇u|p−|u|plog|u|dx−|u|plogλ]dx |
ddλj(λ∗)=0 |
which implies that
λ∗=exp∫Ω[|∇u|pdx−|u|plog|u|]dx∫Ω|u|pdx. |
the statements of (2) and (3) can be shown easily. The last property, (4), is only a simple corollary of the fact that
I(λ∗)=λ∗[λ∗p−1∫Ω(|∇u|p−|u|plog|u|dx−|u|plogλ∗)dx]=λ∗j(λ∗)=0. |
The proof of lemma is complete.
Next we denote
R=(p2enLp)np2, |
Lemma 8. (1) if I(u)>0 then 0<‖u‖p<R,
(2) if I(u)<0 then ‖u‖p>R,
(3) if I(u)=0 then ‖u‖p≥R.
Proof. By the definition of I(u), we have
I(u)≥‖∇u‖pp−∫Ω|u|plog|u|dx=(1−μp)‖∇u‖pp+[μp‖∇u‖pp−∫Ω|u|plog(|u|‖u‖p)dx]−∫Ω|u|plog‖u‖pdx, |
Choosing μ=p, and we apply the logarithmic Sobolev inequality (Lemma 1), we obtain
I(u)≥(np2logp2enLp−log‖u‖p)‖u‖pp, |
if I(u)>0, then
log‖u‖p<log(p2enLp)np2, |
that's mean
‖u‖p<(p2enLp)np2=R, |
and if I(u)<0, we obtain
‖u‖p>(p2enLp)np2=R. |
property (3) we can argue similarly the proof of (2).
The proof of lemma is complete.
Lemma 9. (see [34]) Let f : R+→R+ be a nonincreasing function and σ is a nonnegative constant such that
∫+∞tf1+σ(s)ds≤1ωfσ(0)f(t).∀t≥0. |
Then we have
(a) f(t)≤f(0)e1−ωt, for all t≥0, whenever σ=0,
(b) f(t)≤f(0)(1+σ1+ωσt)1σ, for all t≥0, whenever σ>0.
Remark 2. As in [33], we introduce the following set:
W+1={u∈X0,I(u)>0}.W−1={u∈X0,I(u)<0}. |
Theorem 2. if u0∈W+1,0<J(u0)<M′=Rp2, Then the solution u(x,t) of problem (1.1) admits a global weak solution such that
u(t)∈¯W+1,for0≤t<∞, |
satisfying the energy estimate
∫t0‖us(s)‖22ds+J(u(t))≤J(u0),∀t∈[t,T0). |
Moreover, the solution decays polynomially, namely
‖u‖2≤Cs(p2(1+ζs(p−2)t))1p−2,t≥0,,t≥0, |
where Cs and ζs are positives constants .
Proof. Existence of global weak solutions
It suffices to show that ‖∇u‖pp and ‖u‖pp are bounded independent of t.
In the space W1,p0(Ω), we take a basis {wj}∞j=1 and define the finite dimensional space
Vm=span{w1,w2,...wm,}. |
Let u0m be an element of Vm such that
u0m=m∑j=1αmjwj→u0 strongly in W1,p0(Ω). | (3.1) |
as m→+∞, We find the approximate solution um(x,t) of the problem (1.1) in the form
um(x,t)=m∑j=1αmj(t)wj(x). |
where the coefficients αmj(1≤j≤m) where (αmj(0)=am,j), satisfy the system of ordinary differential equations
(umt,wi)2+((|∇um|p−2∇um),∇wi)2=(|um|pumlog|um|,wi)2−(∮|um|pumlog|um|,wi)2. | (3.2) |
We multiply both sides of (3.2) by α′mi(t),and we take the sum, we get
∫Ωα′mm(t)umt(t)wm(x)dx+∫Ωα′mm(t)|∇um(t)|p−2∇u(t)∇wm(x)dx=∫Ωα′mm(t)|um|p−2(t)um(t)log|um(t)|wm(x)dx, |
that's mean
∫Ω|umt(t)|2dx+∫Ω|∇um(t)|p−2∇um(t)∇umt(t)dx=∫Ω|um|p−2(t)um(t)umt(t)log|um(t)|dx, |
this implies that
‖umt(t)‖2+ddt[1p‖∇um(t)‖p+1p2‖um(t)‖p−1p∫Ω|um|p(t)log|um(t)|dx]=0, |
we deduce
‖umt(t)‖2+ddtJ(um(t))=0, | (3.3) |
by integrating (3.3) with respect to t on [0,t], we obtain the following equality
∫t0‖umt(s)‖2ds+J(um(t))=J(um(0)),0≤t≤Tm, | (3.4) |
where Tm is the maximal existence time of solution umt(x,t).
It follows from (3.1), (3.4), and the continuity of J that
J(um(0))→J(u0), oˊum→+∞, |
with J(u0)<d and
∫t0‖umt(s)‖2ds+J(um(t))<d, 0≤t≤Tm, | (3.5) |
for m large sufficiently large m, We will show that
um(t)∈W+1, ∀t≥0, | (*) |
and for sufficiently large m, and assume that (*) does not hold and let t∗ be the smallest time for which um(t∗)∉W+1. Then, by the continuity of um(t∗)∈∂W+1, we have
J(um(t∗))=d, and I(um(t∗))=0, | (3.6) |
Nevertheless, it is clear that (3.6)1 could not occur by (3.5) while if (3.6)2 holds then, by the definition of d, we have
J(um(t∗))≥infu∈NδJ(u)=d, | (**) |
which also contradicts with (3.5). Thus, (*) is true.
On the other hand, since um(t)∈W+1, and
J(um(t))=1pI(um(t))+1p2‖um(t)‖pp, ∀t∈[0,Tm), |
we deduces from (3.5) that
‖um(t)‖pp<p2d, and ∫t0‖ums(s)‖22ds<d, | (3.7) |
for sufficiently large m and t∈ [0,Tm). Further, by the logarithmic inequality, we have
‖∇um(t)‖pp=pJ(um(t))+∫Ω|um|p(t)log|um(t)|dx−1p‖um(t)‖pp≤pJ(um(0))+∫Ω|um|p(t)(log|um(t)|dx‖um(t)‖p+log‖um(t)‖p)dx≤pJ(um(0))+μp‖∇um(t)‖pp−np2log(pμenLp)‖um(t)‖pp+‖um(t)‖pplog‖um(t)‖p, |
This implies that
(p−μp)‖∇um(t)‖pp≤pJ(um(0))+‖um(t)‖pplog‖um(t)‖p−np2log(pμenLp)‖um(t)‖pp |
Taking μ<p, we deduce that
‖∇um(t)‖pp≤Cd,∀t∈[0,Tm). |
Decay estimates
We define
M(t)=12‖u‖22. |
M′(t)=∫Ωutudx=((|u|p−2ulog|u|,u)2−(∮Ω|u|p−2ulog|u|dx,u)2+‖∇u‖pp)=−I(u) | (3.8) |
for u(t)∈W+1 by using (2.3) and the energy inequality that, we know
‖u‖pp≤p2J(u)≤p2J(u0). | (3.9) |
By using the logarithmic Sobolev inequality in Lemma 1 and we put μ=p, we have
I(u)≥(np2log(p2enLp)−log‖u‖p)‖u‖pp≥(log(p2nLp)np2−logp2J(u0))‖u‖pp=(log(p2nLp)np2p2J(u0))‖u‖pp≥1l2,p(log(p2nLp)np2p2J(u0))‖u‖p2=ζ‖u‖p2, | (3.10) |
where l2,p is a constant in the embedding Lp(Ω)↪L2(Ω),p>2 and ζ=1l2,plogMJ(u0).
From (3.8), we have
∫TtI(u(s))ds=−∫Tt∫Ωus(s)u(s)dxds=−12‖u(T)‖22+12‖u(t)‖22≤12‖u‖22. | (3.11) |
Combining (3.10) and (3.11), it follows that
∫Tt‖u‖p2≤12ζ‖u‖22, ∀t∈[0,T]. | (3.12) |
Let T→+∞ and apply Lemma 9, such that f(t)=‖u(t)‖22,σ=p−22,f(0)=1,ω=12ς
we obtain the following decay estimate
‖u‖2≤Cs(p2(1+ζs(p−2)t))1p−2,t≥0, | (3.13) |
where Cs is positive constant and ζs=14ς.
Definition 1. (Blow-up at+∞) Let u(x,t) be a weak solution of (1.1). We call u(x,t) blow-up at +∞ if the maximal existence time T= +∞ and
limt→+∞‖u(.,t)‖2=+∞ |
Theorem 3. Assume J(u0)<0, then the solution u(x,t) of problem (1.1) is blow-up at +∞. Moreover, if ‖u0‖2≤(−pJ(u0)l2,p)p, the lower bound for blow-up rate can be estimated by
‖u‖22≥‖u0‖22, | (4.1) |
which is independent of t.
Proof. By the definition of J(u) and (2.4), M(t) satisfies
M′(t)=∫Ωut,udx=−‖∇u‖pp+∫Ω(|u|plog|u|−∮|u|pulog|u|)dx=−‖∇u‖pp+∫Ω|u|plog|u|dx=−pJ(u)+1p‖u‖pp≥−pJ(u), | (*) |
by using (2.4) defined in theorem 1 and the condition J(u0)<0, we have
−pJ(u)≥p∫t0‖us(s)‖22ds, | (**) |
so by (*) and (**), we get
M′(t)≥p∫t0‖us(s)‖22ds, | (4.2) |
And by the definition of weak solution, we know that u∈W1,p(Ω) For any t0>0, we claim that
∫t00‖us‖22ds>0, | (4.3) |
Otherwise, there exists t0>0 such that ∫t00‖us‖22ds=0, and hence ut=0 for a.e., (x,t)∈Ω×(0,t0). Then it follows from (4.2) that
−|∇u|p+|u|plog|u|=0, |
for a.e., t∈(0,t0), and then we get from (2.1)
J(u)=1p2∫Ω|u|pdx. |
Combining it with J(u)≤J(u0)≤0, we obtain‖ u‖p=0 for all t∈[0,t0], which contradicts the definition of u. Then (4.3) follows.
Fix t0>0 and let δ=∫t0‖ u‖22ds, then we know that δ is a positive constant. Integrating (4.2) over (t0,t), we obtain
M(t)≥M(t0)+p∫tt0∫t0‖ u(s)‖22dsdτ≥M(t0)+p∫tt0δdτ≥δ(t−t0). | (4.4) |
We have
H′(t)=−J′(t)=‖ut‖22, |
where H(t) defined in lemma 6
Hence
limt→∞H′(t)=limt→∞M(t)=∞. | (4.5) |
And from (4.2), we know
M′(t)=−pJ(u)+1p‖u‖pp≥−pJ(u0)+1p‖u‖pp, | (4.6) |
we have
M′(t)+l2,pMp2(t)≥−1p‖u‖pp−pJ(u0)+l2,pMp2(t)≥−l2,pp‖u‖p2−pJ(u0)+l2,p‖u‖p2≥l2,pp−l2,pp‖u‖p2−pJ(u0)≥−pJ(u0), | (4.7) |
where l2,p is a constant in the embedding Lp(Ω)↪L2(Ω), p>2.
By using Lemma 2.1, J(u0)<0, and ‖u0‖22 ≤(−pJ(u0)l2,p)2p, we have
M(t)≥min{‖u0‖22,(−pJ(u0)l2,p)2p}≥‖u0‖22, |
which means (4.1) is true.
Definition 2. (Finite time blow-up) Let u(x,t) be a weak solution of (1.1).We call u(x,t) blow-up in finite time if the maximal existence time T is finite and
limt→T−‖u(.,t)‖2=+∞. |
Lemma 10. Let ϕ be a positive, twice differentiable function satisfying the following conditions
ϕ(¯t)>0,and ϕ′(¯t)>0, |
for some ¯t∈[0,T), and the inequality
ϕ(t)ϕ′′(t)−α(ϕ′(t))2≥0,∀t∈[¯t,T], | (4.8) |
where α>1. Then we have
ϕ(t)≥(1ϕ1−α(¯t)−σ(t−¯t)),t∈[¯t,T∗). |
with σ is a positive constant, and
T∗=¯t+ϕ(t)(α−1)ϕ′(¯t). |
This implies
limt→T∗ϕ(t)=∞. |
Theorem 4. Assume 0<J(u0)<M and u∈W−1, then the solution u(x,t) of problem (1.1) is non-extinct in finite time, defined by
T∗=¯t+∫t0‖u(s)‖22ds(p−22)‖u(¯t)‖22,s∈[¯t,T∗). |
Proof. we define the functional
Γ(t)=∫t0‖u(s)‖22ds. | (4.9) |
Then one has
Γ′(t)=‖u(t)‖22, | (4.10) |
and
Γ′′(t)=2∫Ωutudx=−2‖∇u(t)‖pp+2∫Ω|u|plog|u|dx=−2pJ(u)+2p‖u(t)‖pp, | (4.11) |
by using (2.4) in theorem 1, we have
−2pJ(u)≥−2pJ(u0)+2p∫t0‖us(s)‖22ds, | (4.12) |
by lemma 8 for I(u)<0, which implies
‖u(t)‖pp≥R, | (4.13) |
by (4.13) and (4.14), we get
Γ′′(t)≥−2pJ(u0)+2p∫t0‖us(s)‖22ds+2p‖u(t)‖pp=2p(1p2‖u(t)‖pp−J(u0))+2p∫t0‖us(s)‖22ds≥2p(M−J(u0))+2p∫t0‖us(s)‖22ds, | (4.14) |
where M=Rp2.
In other hand we have
Γ′(t)=Γ′(t)+∫t0Γ′′(s)ds≥2p(M−J(u0))t≥0,t∈[0,t], | (4.15) |
also, we have
14(Γ′(t))2≤(∫t0∫Ωus(s)u(s)dxds)2≤∫t0‖u(s)‖22ds∫t0‖us(s)‖22ds, | (4.16) |
Now, multiplying (4.15) by Γ(t), we get
Γ′′(t)Γ(t)≥2p(M−J(u0))Γ(t)+2p∫t0‖us(s)‖22dsΓ(t)=2p(M−J(u0))Γ(t)+2p∫t0‖us(s)‖22ds∫t0‖u(s)‖22ds, | (4.17) |
by using (4.17) in (4.18), we obtain
Γ′′(t)Γ(t)≥2p(M−J(u0))Γ(t)+p2(Γ′(t))2, for all t∈[0,T]. | (4.18) |
This follows
Γ′′(t)Γ(t)−p2(Γ′(t))2≥2p(M−J(u0))Γ(t),for all t∈[0,T]. | (4.19) |
By virtue of lemma 10, where α=p2>1, and ϕ(t)=Γ(t), we get
there exists T∗>0 such that
limt→T−∗Γ(t)=+∞, |
which implies
limt→T−∗∫t0‖u(s)‖22ds=+∞, |
therefore, we get
limt→T−∗‖u(t)‖22=+∞. |
This ends the proof.
In this work, by using the logarithmic Sobolev inequality and potential wells method, we study the initial boundary value problem of a nonlocal heat equations with logarithmic nonlinearity in a bounded domain, where we obtain the decay, blow-up and non-extinction of solutions under some conditions, and the results extend the results of a recent paper Lijun Yan and Zuodong Yang [13]. In our next study, we will try to apply an alternative approach using the variational principle that has been presented in previous studies [35].
The authors declare no conflict of interest.
[1] |
L. O. Chua, L. Yang, Cellular neural networks: Theory, IEEE Trans. Circuits Syst., 35 (1988), 1257–1272. https://doi.org/10.1109/31.7600 doi: 10.1109/31.7600
![]() |
[2] | K. Gopalsamy, Leakage delays in BAM, J. Math. Anal. Appl., 325 (2007), 1117–1132. https://doi.org/10.1016/j.jmaa.2006.02.039 |
[3] |
C. Li, T. Huang, On the stability of nonlinear systems with leakage delay, J. Franklin Inst., 346 (2009), 366–377. https://doi.org/10.1016/j.jfranklin.2008.12.001 doi: 10.1016/j.jfranklin.2008.12.001
![]() |
[4] |
X. Li, J. Cao, Delay-dependent stability of neural networks of neutral type with time delay in the leakage term, Nonlinearity, 23 (2010), 1709–1726. https://doi.org/10.1088/0951-7715/23/7/010 doi: 10.1088/0951-7715/23/7/010
![]() |
[5] |
S. Peng, Global attractive periodic solutions of BAM neural networks with continuously distributed delays in the leakage terms, Nonlinear Anal. Real World Appl., 11 (2010), 2141–2151. https://doi.org/10.1016/j.nonrwa.2009.06.004 doi: 10.1016/j.nonrwa.2009.06.004
![]() |
[6] |
X. Li, R. Rakkiyappan, P. Balasubramaniam, Existence and global stability analysis of equilibrium of fuzzy cellular neural networks with time delay in the leakage term under impulsive perturbations, J. Franklin Inst., 348 (2011), 135–155. https://doi.org/10.1016/j.jfranklin.2010.10.009 doi: 10.1016/j.jfranklin.2010.10.009
![]() |
[7] | M. Ali, M. Hymavathi, B. Priya, S. Kauser, G. Thakur, The periodic Ambrosetti-Prodi problem for nonlinear perturbations of the p-Laplacian, AIMS Mathematics, 6 (2021), 3205–3241. |
[8] |
L. Zhang, Q. Song, Z. Zhao, Stability analysis of fractional-order complex-valued neural networks with both leakage and discrete delays, Appl. Math. Comput., 298 (2017), 296–309. https://doi.org/10.1016/j.amc.2016.11.027 doi: 10.1016/j.amc.2016.11.027
![]() |
[9] |
A. Singh, J. N. Rai, Stability analysis of fractional order fuzzy cellular neural networks with leakage delay and time varying delays, Chinese J. Phys., 73 (2021), 589–599. https://doi.org/10.1016/j.cjph.2021.07.029 doi: 10.1016/j.cjph.2021.07.029
![]() |
[10] |
C. D. Zheng, Y. Wang, Z. Wang, Stability analysis of stochastic fuzzy Markovian jumping neural networks with leakage delay under impulsive perturbations, J. Franklin Inst., 351 (2014), 1728–1755. https://doi.org/10.1016/j.jfranklin.2013.12.013 doi: 10.1016/j.jfranklin.2013.12.013
![]() |
[11] |
J. Alzabut, S. Tyagi, S. Abbas, Discrete fractional-order BAM neural networks with leakage delay: Existence and stability results, Asian J. Control, 22 (2020), 143–155. https://doi.org/10.1002/asjc.1918 doi: 10.1002/asjc.1918
![]() |
[12] |
T. Zhang, L. Xiong, Periodic motion for impulsive fractional functional differential equations with piecewise Caputo derivative, Appl. Math. Lett., 101 (2020), 106072. doilinkhttps://doi.org/10.1016/j.aml.2019.106072 doi: 10.1016/j.aml.2019.106072}
![]() |
[13] |
T. Zhang, Y. Li, Global exponential stability of discrete-time almost automorphic Caputo CFabrizio BAM fuzzy neural networks via exponential Euler technique, Knowledge-Based Systems, 246 (2022), 108675. https://doi.org/10.1016/j.knosys.2022.108675 doi: 10.1016/j.knosys.2022.108675
![]() |
[14] |
T. Zhang, H. Qu, J. Zhou, Asymptotically almost periodic synchronization in fuzzy competitive neural networks with Caputo-Fabrizio operator, Fuzzy Sets Syst., 471 (2023), 108676. https://doi.org/10.1016/j.fss.2023.108676 doi: 10.1016/j.fss.2023.108676
![]() |
[15] |
X. Yang, F. Li, Y. Long, X. Cui, Existence of periodic solution for discrete-time cellular neural networks with complex deviating arguments and impulses, J. Franklin Inst., 347 (2010), 559-566. https://doi.org/10.1016/j.jfranklin.2009.12.004 doi: 10.1016/j.jfranklin.2009.12.004
![]() |
[16] |
J. H. Park, Further result on asymptotic stability criterion of cellular neural networks with time-varying discrete and distributed delays, Appl. Math. Comput., 182 (2006), 1661–1666. https://doi.org/10.1016/j.amc.2006.06.005 doi: 10.1016/j.amc.2006.06.005
![]() |
[17] |
F. Kong, Q. Zhu, Finite-time stabilization of discontinuous fuzzy neutral-type neural networks with D operator and multiple time-varying delays, Fuzzy Sets Syst., 449 (2022), 32–55. https://doi.org/10.1016/j.fss.2022.02.006 doi: 10.1016/j.fss.2022.02.006
![]() |
[18] |
H. Zhang, Q. Ma, J. Lu, Y. Chu, Y. Li, Synchronization control of neutral-type neural networks with sampled-data via adaptive event-triggered communication scheme, J. Franklin Inst., 358 (2021), 1999–2014. https://doi.org/10.1016/j.jfranklin.2021.01.005 doi: 10.1016/j.jfranklin.2021.01.005
![]() |
[19] |
S. A. Karthick, R. Sakthivel, C. Aouiti, A. Leelamani, Memory feedback finite-time control for memristive neutral-type neural networks with quantization, Chinese J. Phys., 70 (2021), 271–287. https://doi.org/10.1016/j.cjph.2019.09.016 doi: 10.1016/j.cjph.2019.09.016
![]() |
[20] | J. Hale, Theory of functional differential equations, New York: Springer-Verlag, 1993. |
[21] |
S. Saravanan, M. S. Ali, A. Alsaedi, B. Ahmad, Finite-time passivity for neutral-type neural networks with time-varying delays via auxiliary function-based integral inequalities, Nonlinear Anal. Model. Control, 25 (2020), 206–224. https://doi.org/10.15388/namc.2020.25.16513 doi: 10.15388/namc.2020.25.16513
![]() |
[22] |
X. Zhang, X. F. Fan, Y. Xue, Y. T. Wang, W. Cai, Robust exponential passive filtering for uncertain neutral-type neural networks with time-varying mixed delays via Wirtinger-based integral inequality, Int. J. Control Autom. Syst., 15 (2017), 585–594. https://doi.org/10.1007/s12555-015-0441-0 doi: 10.1007/s12555-015-0441-0
![]() |
[23] |
R. Rakkiyappan, P. Balasubramaniam, New global exponential stability results for neutral type neural networks with distributed time delays, Neurocomputing, 71 (2008), 1039–1045. https://doi.org/10.1016/j.neucom.2007.11.002 doi: 10.1016/j.neucom.2007.11.002
![]() |
[24] |
J. Park, O. M. Kwon, Global stability for neural networks of neutral-type with interval time-varying delays, Chaos Solitons Fractals, 41 (2009), 1174–1181. https://doi.org/10.1016/j.chaos.2008.04.049 doi: 10.1016/j.chaos.2008.04.049
![]() |
[25] | R. E. Gaines, J. Mawhin, Coincidence degree and nonlinear differential equations, In: Lecture notes in mathematics, Berlin: Springer, 568 (1977). |
[26] |
B. Du, L. Guo, W. Ge, S. Lu, Periodic solutions for generalized Lieˊnard neutral equation with variable parameter, Nonlinear Anal., 70 (2009), 2387–2394. https://doi.org/10.1016/j.na.2008.03.021 doi: 10.1016/j.na.2008.03.021
![]() |
[27] |
K. Gopalsamy, X. Z. He, Delay-independent stability in bidirectional associative memory networks, IEEE Trans. Neural Networ., 5 (1994), 998–1002. https://doi.org/10.1109/72.329700 doi: 10.1109/72.329700
![]() |
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