







摘要: 利用Schauder不動點定理和Banach壓縮映射原理, 研究一類具有時滯的適型分數階脈沖微分方程邊值問題, 建立了其解的存在唯一性定理, 并基于此得到了Ulam-Hyers穩定性和Ulam-Hyers-Rassias穩定性的結論, 最后給出一個實例驗證理論結果.
關鍵詞: 適型分數階導數; 脈沖; 時滯; 存在唯一性; Ulam-Hyers穩定性; Ulam-Hyers-Rassias穩定性
中圖分類號: O175.8文獻標志碼: A文章編號: 1671-5489(2025)02-0287-10
Existence, Uniqueness and Stability of Solutions of Conformable Fractional Differential Equation
ZHANG Luchao, LIU Xiping, JIA Mei, YU Zhensheng
(College of Science, University of Shanghai for Science and Technology, Shanghai 200093, China)
Abstract: By usingSchauder fixed point theorem and Banach compression mapping principle, we studied a class of conformable fractiona
l impulsive differential equation boundary value problems with delay, and established the existence and uniqueness theorems of the solutions. Based on this,
we obtained the conclusions of Ulam-Hyers stability and Ulam-Hyers-Rassias stability. Finally, we provided anexampleto verify the theoretical results.
Keywords: conformable fractional derivative; impulsive; delay; existence and uniqueness; Ulam-Hyers stability; Ulam-Hyers-Rassias stability
0 引 言
分數階微分方程應用廣泛, 目前, 關于分數階微分方程邊值問題理論與應用的研究已取得了許多成果[1-8].例如: Khalil等[7]提出了適型分數階導數和分數階積分的定義; Abdeljawad[8]拓展了適型分數階微積分的定義, 提出并討論了其鏈式法則、 指數函數、 Gronwall不等式、 分部積分、 Taylor冪級數展開、 Laplace變換和線性微分系統等. 近年來, 對適型分數階導數和積分的研究也取得了豐富成果[9-12].例如: Li等[9]研究了適型分數階微分方程初值問題解的存在性和穩定性; Thaiprayoon等[10]利用上下解方法和單調迭代技術研究了非線性時滯脈沖適型分數階微分方程解的存在性; Wan等[11]研究了適型脈沖微分方程反周期邊值問題解的存在性和穩定性; 張敏等[12]利用Leray-Schauder度理論和Banach壓縮映射原理研究了適型分數階時滯微分方程邊值問題解的存在性與唯一性.Ulam穩定性理論由于廣泛應用于最優化、 生物學、 經濟學等領域, 因此得到廣泛關注[9,11,13-17].Wang等[13]研究了一階脈沖常微分方程的Ulam穩定性; Wang等[14]研究了非線性脈沖切換耦合演化方程初值問題的Ulam穩定性; Muthaiah等[15]研究了非線性耦合Caputo-Hadamard型分數階微分
系統解的存在性和Ulam穩定性; Agarwal等[16]研究了Caputo分數階微分方程邊值問題的Ulam穩定性; 白玉潔等[17]研究了一類含有Riemann-Liouville
分數階導數的時滯隨機發展方程溫和解的存在唯一性和Ulam穩定性.
但上述研究多數是關于初值問題的Ulam穩定性, 而關于分數階微分方程邊值問題的Ulam穩定性研究目前報道較少. 基于此, 本文考慮一類具有時滯的適型分數階脈沖微分方程邊值問題解的存在唯一性和Ulam穩定性:
Tα0x(t)+f1(t,x(t),x(t+τ))=0,t∈(0,t0),Tαt0x(t)+f2(t,x(t),x(t-τ))=0,t∈(t0,1),
Δx(t)t=t0JB)〗=p(x(t0)), Δx′(t)t=t0=q(x(t0)),
x(0)=x′(1)=0,(1)
其中1lt;αlt;2, Tαβ是以β為起點的α階適型分數階微分算子, 0lt;t0lt;1, J=[0,1], p,q∈C(瘙綆,瘙綆), 0≤τ≤min{t0,1-t0}, f1,f2∈C(J×瘙綆2,瘙綆), Δx(t)t=t0=x(t+0)-x(t-0), Δx(t)t=t0=x(t+0)-x(t-0), x(t+0),x(t-0),x′(t+0),x′(t-0)分別是x(t)和x′(t)在t0處的左右極限.
1 預備知識
令J1=[0,t0], J2=(t0,1], J′=J\{t0}, λ=max{t0,1-t0}. 設分段連續函數空間
PC(J,瘙綆)={x: J→瘙綆x∈C(J′,瘙綆), x(t+0)和x(t-0), 使得x(t-0)=x(t0)},
并賦予范數‖x‖PC=supt∈Jx(t), 則PC(J,瘙綆)是Banach空間.
定義1[8]設γ∈(n,n+1], x:[a,+∞)→瘙綆, 對任意的tgt;a, x是n階可微的, 則函數x在tgt;a處的γ階適型分數階導數定義為
Tγax(t)=limε→0x(n)(t+ε(t-a)n+1-γ)-x(n)(t)ε.
注1 給定γ∈(0,1], 如果x可微, 則Tγax(t)=(t-a)1-γx′(t). 給定γ∈(n,n+1], 有Tγa(t-a)k=0, 其中k=0,1,2,…,n.
定義2[8]設γ∈(n,n+1], x:[a,+∞)→瘙綆, 則函數x在tgt;a處的γ階適型分數階積分定義為
Iγax(t)=1n!∫ta(t-s)nsγ-n-1x(s)ds.
引理1[8]設γ∈(n,n+1], x:[a,+∞)→瘙綆使得x(n)(t)連續, 則對所有的tgt;a, 有
TγaIγax(t)=x(t).
引理2[8]設γ∈(n,n+1], x:[a,+∞)→瘙綆對tgt;a是(n+1)階可微的, 則對所有的tgt;a, 有
IγaTγax(t)=x(t)-∑nk=0x(k)(a)(t-a)kk!.
引理3 設1lt;αlt;2, y1,y2∈C(J,瘙綆), p,q∈瘙綆, 則線性適型分數階脈沖微分方程邊值問題
Tα0+x(t)+y1(t)=0,t∈(0,t0),Tαt+0x(t)+y2(t)=0,t∈(t0,1),
Δx(t)t=t0=p,Δx′(t)t=t0=q,x(0)=x′(1)=0(2)
有唯一解
x(t)=∫10G(t,s)R(s,y1,y2)ds+φ(t),
其中G(t,s)=s,0≤s≤t≤1,t,0≤t≤s≤1,(3)
R(s,y1,y2)=R(s,y1(s),y2(s))=sα-2y1(s),0≤s≤t0≤1,
(s-t0)α-2y2(s),0≤t0≤s≤1,(4)
φ(t,p,q)=-qt,t∈J1,p-qt0,t∈J2.(5)
證明: 假設x=x(t)是邊值問題(2)的解, 則對任意的t∈J1, 存在常數c10,c11∈瘙綆, 使得
x(t)=-∫t0(t-s)sα-2y1(s)ds+c10+c11t,x′(t)=-∫t0sα-2y1(s)ds+c11.
由x(0)=0知c10=0, 故
x(t-0)=-∫t00(t0-s)sα-2y1(s)ds+c11t0,x′(t-0)=-∫t00sα-2y1(s)ds+c11.
對任意的t∈J2, 存在常數c20,c21∈瘙綆, 使得
x(t)=-∫tt0(t-s)(s-t0)α-2y2(s)ds+c20+c21(t-t0),x′(t)=-∫tt0(s-t0)α-2y2(s)ds+c21,
x(t+0)=c20, x′(t+0)=c21,(6)x′(1)=-∫1t0(s-t0)α-2y2(s)ds+c21.
再由x′(1)=0知c21=∫1t0(s-t0)α-2y2(s)ds.
考慮脈沖條件
Δx(t)t=t0=x(t+0)-x(t-0)=c20+∫t00(t0-s)sα-2y1(s)ds-c11t0,
Δx′(t)t=t0=x′(t+0)-x′(t-0)=c21+∫t00sα-2y1(s)ds-c11.
由脈沖條件Δx(t)t=t0=p, Δx′(t)t=t0=q, 再結合式(6)可得
c11=∫t00sα-2y1(s)ds+∫1t0(s-t0)α-2y2(s)ds-q,c20=∫t00sα-1y
1(s)ds+t0∫1t0(s-t0)α-2y2(s)ds+p-qt0,
故對任意的t∈J1, 有
x(t)=∫t0sα-1y1(s)ds+∫t0ttsα-2y1(s)ds+∫1t0t(s-t0)α-2y2(s)ds-qt,
對任意的t∈J2, 有
x(t)=∫1tt(s-t0)α-2y2(s)ds+∫tt0s(s-t0)α-2y2(s)ds+∫t00sα-1y1(s)ds+p-qt0.
因此, x(t)=∫10G(t,s)R(s,y1,y2)ds+φ(t,p,q). 證畢.
由函數G(t,s)的定義, 易知對任意的t,s∈[0,1], 有
G(t,s)≤1.(7)
記
φ(t,p,q)=φ(t,p(x(t0)),q(x(t0)))=-tq(x(t0)),t∈J1,p(x(t0))-t0q(x(t0)),t∈J2,(8)
對任意的x∈PC(J,瘙綆), 設
Λx(t)=∫10G(t,s)R(s,f1,f2)ds+φ(t,p,q),(9)
則易知Λ: PC(J,瘙綆)→PC(J,瘙綆), 并且邊值問題(1)與積分方程(9)等價. 即x=x(t)是邊值問題(1)的解當且僅當x=x(t)是算子Λ的不動點.
2 存在唯一性
為方便敘述, 下面給出假設條件.
(H1) 存在函數ωi,μi,υi∈C(Ji,[0,+∞))(i=1,2), 使得對任意的u,v∈瘙綆, t∈Ji, 有
fi(t,u,v)≤ωi(t)+μi(t)u+υi(t)v,
且記ω*=max{supt∈J1 ω1(t),supt∈J2 ω2(t)},μ*=max{supt∈J1 μ1(t),supt∈J2 μ2(t)}, υ*=max{supt∈J1 υ1(t),supt∈J2 υ2(t)};
(H2) 存在常數Mp,Np,Mq,Nqgt;0, 使得對任意的u∈瘙綆, 有
p(u)≤Mpu+Np,q(u)≤Mqu+Nq;
(H3) 存在常數Mfi,Nfi, 使得對任意的u,v,u,v∈瘙綆, t∈Ji(i=1,2), 有
fi(t,u,v)-fi(t,u,v)≤Mfiu-u+Nfiv-v;
(H4) 存在常數l,l*gt;0, 使得對任意的u,v,u,v∈瘙綆, 有
p(u)-p(u)≤lu-u,q(u)-q(u)≤l*u-u.
定理1 假設(H1)和(H2)成立, 若2λα-1(μ*+υ*)lt;(α-1)(1-Mp-Mq)成立, 則適型分數階時滯脈沖微分方程邊值問題(1)至少有一個解.
證明: 令
r≥2λα-1ω*+(α-1)(Np-Nq)(α-1)(1-Mp-Mq)-2λα-1(μ*+υ*),
并設
Br={xx∈PC(J,瘙綆),‖x‖PC≤r}.
1) 證明Λ: Br→Br.
對任意的x∈Br和任意的t∈Jk(k=1,2), 由條件(H1)可得
f1(t,x(t),x(t+τ))≤ω1(t)+μ1(t)x(t)+υ1(t)x(t+τ)≤ω*+(μ*+υ*)r,
f2(t,x(t),x(t-τ))≤ω2(t)+μ2(t)x(t)+υ2(t)x(t-τ)≤ω*+(μ*+υ*)r.
從而由式(7)和式(9), 可得
Λx(t)≤∫10G(t,s)R(s,f1,f2)ds+φ(t,p,q)≤
∫10R(s,f1,f2)ds+max{tq(x(t0)),p(x(t0))-t0q(x(t0))}≤
∫t00sα-2f1(s,x(s),x(s+τ))ds+∫1t0(s-t0)α-2f2(s,x(s),x(s-τ))ds+
p(x(t0))+q(x(t0))≤1α-1tα-10(ω*+(μ*+υ*)r)+1α-1(1-t0)α-1
(ω*+(μ*+υ*)r)+(Mp+Mq)r+Np+Nqlt;(α-1)r-(2λα-1(
μ*+υ*))rα-1+2λα-1(μ*+υ*)α-1r=r.
故‖Λx‖PC≤r.
2) 證明Λ: Br→Br是全連續算子.
設xn,x∈Br(n=1,2,…), 且‖xn-x‖PC→0, n→∞. 由于f1,f2,p,q是連續函數, 因此對任意的εgt;0, 存在正整數N, 使得對任意的t∈Ji, 當n≥N時, 有
f1(t,xn(t),xn(t+τ))-f1(t,x(t),x(t+τ))lt;ε,f2(t,xn(t),xn(t-τ))-f2(t,x(t),x(t-τ))lt;ε,
p(xn(t))-p(x(t))lt;ε,q(xn(t))-q(x(t))lt;ε.
因此, 對任意的t∈Jk(k=1,2), 有
Λxn(t)-Λx(t)≤∫10G(t,s)R(s,f1(s,xn(s),xn(s+τ)),
f2(s,xn(s),xn(s-τ)))-R(s,f1(s,x(s),x(s+τ)),f2(s,x(s),x(s-τ)))ds+
max{tq(xn(t0))-q(x(t0)),p(xn(t0))-p(x(t0))+t0q(xn(t0))-q(x(t0))}≤
∫10R(s,f1(s,xn(s),xn(s+τ)),f2(s,xn(s),xn(s-τ)))-R(s,f1(s,x(s),x(s+τ)),f2(s,x(s),x(s-τ)))ds+2ε≤∫t00sα-2f1(s,xn(s),xn(s+τ))-f1(s,x(s),x(s+τ)
)ds+∫1t0(s-t0)α-2f2(s,xn(s),xn(s-τ))-f2(s,x(s),x(s-τ))ds+2ε≤2(λα-1+α-1)α-1ε.
故Λ: Br→Br是連續的.
對任意的x∈Br, t1,t2∈Jk(k=1,2), 且t1lt;t2, 有
Λx(t2)-Λx(t1)≤∫10G(t2,s)-G(t1,s)R(s,f1,f2)d
s+φ(t2,p,q)-φ(t1,p,q)≤(t2-t1)∫10R(s,f1,f2)ds+(t2-t1)q(x(t0))
≤(t2-t1)∫t00sα-2f1(s,x(s),x(s+τ))ds+∫1t0(s-t0)α-2f2(s,x(s)
,x(s-τ))ds+(t2-t1)(Mqr+Nq)≤(t2-t1)2λα-1α-1(ω*+(μ*+υ*)r)+(Mqr+Nq),
因此,
Λx(τ2)-Λx(τ1)→0, t1→t2, t1,t2∈Jk, k=1,2.
由上述證明可知, 算子Λ等度連續. 由Arzela-Ascoli定理[18]知算子Λ是緊的, 故算子Λ是全連續的. 由Schauder不動點定理[1]可知算子Λ在Br上有
不動點, 即適型分數階時滯脈沖微分方程邊值問題(1)至少有一個解. 證畢.
定理2 假設(H3)和(H4)成立, 若不等式
λα-1(Mf1+Nf1+Mf2+Nf2)+(α-1)(l+l*)lt;α-1(10)
成立, 則適型分數階時滯脈沖微分方程邊值問題(1)有唯一解.
證明: 對任意的x1,x2∈PC(J,瘙綆)和任意的t∈Jk(k=1,2), 由條件(H3)可知
f1(s,x2(s),x2(s+τ))-f1(s,x1(s),x1(s+τ))≤(Mf1+Nf1)‖x2-x1‖PC,
f2(s,x2(s),x2(s-τ))-f2(s,x1(s),x1(s-τ))≤(Mf2+Nf2)‖x2-x1‖PC,
于是, 有
Λx2(t)-Λx1(t)≤∫10G(t,s)R(s,f1(s,x2(s),x2(s+τ)),f2(s,x2(s),x2(s-τ)))-R(s,f1(s,x1(s
),x1(s+τ)),f2(s,x1(s),x1(s-τ)))ds+max{tq(x2(t0))-q(x2(t0)),p(x2(t0))-p(x1(t0))+t0q(x2(t0))-q(x1(t0))}≤∫t00sα-2f1(s,x2(s),x2(s+τ))-f1(s,x1(s),x1(s+τ))ds
+∫1t0(s-t0)α-2f2(s,x2(s),x2(s-τ))-f2(s,x1(s),x1(s-τ))ds+lx2(t0)-x1(t0)+
l*x2(t0)-x1(t0)≤λα-1(Mf1+Nf1+Mf2+Nf2)+(α-1)(l+l*)α-1‖x2-x1‖PC,
因此,
‖Λx2-Λx1‖PC≤λα-1(Mf1+Nf1+Mf2+Nf2)+(α-1)(l+l*)α-1‖x2-x1‖PC.
由式(10)可知Λ是壓縮的, 因此由Banach壓縮映射原理[1]知, Λ在PC(J,瘙綆)上有唯一的不動點, 即邊值問題(1)有唯一解. 證畢.
3 Ulam穩定性
定義3[9]設x∈PC(J,瘙綆)是邊值問題(1)的解, z∈PC(J,瘙綆)是不等式
Tα0z(t)-f1(t,z(t),z(t+τ))≤ε,t∈[0,t0],Tαt0z(t)-f2(t,z(t),z(t-τ))
≤ε,t∈(t0,1],Δz(t)t=t0-p(z(t0))≤ε,Δz′(t)t=t0-q(z(t0))≤ε,
z(0)=z′(1)=0(11)
的解, 如果存在常數cf1,f2gt;0, 使得對任意的εgt;0, 有
‖z-x‖PC≤cf1,f2ε
成立, 則稱邊值問題(1)具有Ulam-Hyers穩定性.
定義4[9]設x∈PC(J,瘙綆)是邊值問題(1)的解, z∈PC(J,瘙綆)是不等式
Tα0z(t)-f1(t,z(t),z(t+τ))≤εg(t),t∈[0,t0],Tαt0z(t)-f2(t,z(t),z(t-τ))≤εg(t),t∈(t0,1],Δz(t)t=t0-p(z(t0))≤εδ,Δz′(t)t=
t0-q(z(t0))≤εδ,z(0)=z′(1)=0(12)
的解, 如果存在連續函數g: J→(0,+∞)和常數δ, cf1,f2,ggt;0, 使得對任意的εgt;0, 有
‖z-x‖PC≤cf1,f2,gε(g(t)+δ)
成立, 則稱邊值問題(1)具有Ulam-Hyers-Rassias穩定性.
注2 函數z∈PC(J,瘙綆)是不等式(11)的解, 當且僅當存在函數1,2∈PC(J,瘙綆)和常數γ,γ′∈瘙綆, 使得下列結論成立:
1) 1(t)≤ε, 2(t)≤ε, γ≤ε, γ′≤ε, t∈J;
2) Tα0z(t)=f1(t,z(t),z(t+τ))+1(t), t∈(0,t0);
3) Tαt0z(t)=f2(t,z(t),z(t-τ))+2(t), t∈(t0,1];
4) Δz(t)t=t0=p(z(t0))+γ;
5) Δz′(t)t=t0=q(z(t0))+γ′;
6) z(0)=z(1)=0.
注3 函數z∈PC(J,瘙綆)是不等式(12)的解, 當且僅當存在函數1,2∈PC(J,瘙綆)和常數γ,γ′∈瘙綆, 使得下列結論成立:
1) 1(t)≤εg(t), 2(t)≤εg(t), γ≤εδ, γ′≤εδ, t∈J;
2) Tα0z(t)=f1(t,z(t),z(t+τ))+1(t), t∈(0,t0);
3) Tαt0z(t)=f2(t,z(t),z(t-τ))+2(t), t∈(t0,1);
4) Δz(t)t=t0=p(z(t0))+γ;
5) Δz′(t)t=t0=q(z(t0))+γ′;
6) z(0)=z(1)=0.
由引理3可得以下引理.
引理4 假設1,2∈PC(J,瘙綆), γ,γ′∈瘙綆, 則適型分數階時滯脈沖微分方程邊值問題
Tα0z(t)=f1(t,z(t),z(t+τ))+1(t),t∈(0,t0),Tαt0z(t)=f2(t,z(t),z(t-τ))+2(t),t∈(t0,1),
Δz(t)t=t0=p(z(t0))+γ,Δz′(t)t=t0=q(z(t0))+γ′,z(0)=z(1)=0
的等價積分方程為
z(t)=∫10G(t,s)R(s,f1+1,f2+2)ds+φ(t,p+γ,q+γ′).
定理3 設定理2的所有條件都滿足, 則適型分數階時滯脈沖微分方程邊值問題(1)具有Ulam-Hyers穩定性.
證明: 因為定理2的所有條件都滿足, 所以邊值問題(1)存在唯一解x∈PC(J,瘙綆). 設z∈PC(J,瘙綆)是不等式(11)的解, 則由注2和引理4知, 對任意的t∈Jk(k=1,2), 有
z(t)-x(t)=∫10G(t,s)R(s,f1+1,f2+2)ds+φ(t,p+γ,q+γ′)-∫10G(t,s)R
(s,f1,f2)ds-φ(t,p,q)≤∫10G(t,s)R(s,f1+1,f2+2)-R(s,f1,f2
)ds+(p(z(t0))+γ)-t0(q(z(t0))+γ′)-(p(x(t0))-t0q(x(t0)))≤∫t00sα-2f1(s,z(s),z
(s+τ))+1-f1(s,x(s),x(s+τ))ds+∫1t0(s-t0)α-2f2(s,z(s),z(s-τ))+2-f2(s,x(s),x(s-τ))ds
+γ+γ′+p(z(t0))-p(x(t0))+q(z(t0))-q(x(t0))≤∫t00sα
-2ds(Mf1+Nf1)‖z-x‖PC+∫1t0(s-t0)α-2ds(Mf2+Nf2)‖z-x‖PC+
∫t0sα-2ds1+∫1t0(s-t0)α-2ds2+γ+γ′+(l+l
*)‖z-x‖PC≤λα-1(Mf1+Nf1+Mf2+Nf2)+(α-1)(l+l*)
α-1‖z-x‖PC+2λα-1+α-1α-1ε,
故
‖z-x‖PC≤λα-1(Mf1+Nf1+Mf2+Nf2)+(α-1)(l+l*)α-1‖z-x‖PC+2λα-1+α-1α-1ε.
由式(10)可得
‖z-x‖PC≤2(λα-1+α-1)(α-1)(1-l-l*)-λα-1(Mf1+Nf1+Mf2+Nf2)ε.
記
cf1,f2∶=2(λα-1+α-1)(α-1)(1-l-l*)-λα-1(Mf1+Nf1+Mf2+Nf2),
則‖z-x‖PC≤cf1,f2ε.
根據定義3, 適型分數階時滯脈沖微分方程邊值問題(1)具有Ulam-Hyers穩定性. 證畢.
定理4 設定理2的所有條件都滿足, 如果存在連續函數g: J→(0,+∞)和常數cggt;0, 使得對任意的t∈J, 有
∫t00sα-2g(s)ds≤cgg(t),∫1t0(s-t0)α-2g(s)ds≤cgg(t)
成立, 則適型分數階時滯脈沖微分方程邊值問題(1)具有Ulam-Hyers-Rassias穩定性.
證明: 因為定理2的所有條件都滿足, 所以邊值問題(1)存在唯一解x∈PC(J,瘙綆). 設z∈PC(J,瘙綆)是不等式(12)的解, 則由注3和引理4知, 類似定理3, 對任意的t∈Jk(k=1,2), 有
z(t)-x(t)=∫10G(t,s)R(s,f1+1,f2+2)ds+φ(t,p+γ,q+γ′)-∫10G(t,s)R(s,f1,f2)ds-φ(t,p,q)≤∫10R(s,f1+1,f2+2)-R(s,f1,f2)ds+γ+γ′+p(z(t0))-p(x(t0))+q(z(t0))-q(x(t0))≤∫t00sα-2ds(Mf
1+Nf1)‖z-x‖PC+∫1t0(s-t0)α-2ds(Mf2+Nf2)‖z-x‖PC+(l+l*)‖z-x‖PC+
∫t00sα-21(s)ds+∫1t0(s-t0)α-22(s)ds+γ+γ′
≤λα-1(Mf1+Nf1+Mf2+Nf2)+(α-1)(l+l*)α-1‖z-x‖PC+2(cgg(t)+δ)ε.
由式(10)可得‖z-x‖PC≤cf1,f2,g(2cgg(t)+2δ)ε,
其中
cf1,f2,g∶=α-1(α-1)(1-l-l*)-λα-1(Mf1+Nf1+Mf2+Nf2).
根據定義4, 適型分數階時滯脈沖微分方程邊值問題(1)具有Ulam-Hyers-Rassias穩定性. 證畢.
4 應用實例
考慮邊值問題
T3/20x(t)=115e2t+x(t)1+t+xt+13,t∈
0,12,T3/21/2x(t)=110sin t+x(t)1+t+x
t-13,t∈12,1,Δx(t)t=1/2
=x(1/2)10+x(1/2), Δx′(t)t=1/2=x(1/2)20+x(1/2),x(0)=x(1)=0,(13)
其中α=32, t0=12, τ=13, λ=12,
f1(t,x(t),x(t+τ))=115e2t+x(t)1+t+xt+13, t∈0,12, px12=x(1/2)10+x(1/2),
f2(t,x(t),x(t-τ))=110sin t+x(t)1+t+xt-13, t∈12,1, qx12=x(1/2)2
0+x(1/2).
設ω1(t)=e2t15, μ1(t)=115(1+t), υ1(t)=115, ω2(t)=sin t10, μ2(t)=110(1+t), υ2(t)=110,
則ω*=e15, μ*=110, υ*=110.
顯然,
Mp=110, Np=1, Mq=120, Nq=1, Mf1=Nf1=115, Mf2=Nf
2=110, l=110, l*=120.
對任意的u,v,u,v∈瘙綆, t∈[0,1], 有
f1(t,u,v)≤e2t15+115(1+t)u+115v,
f2(t,u,v)≤sin t10+110(1+t)u+110v,
p(u)≤110u+1, q(u)≤120u+1,
f1(t,u,v)-f1(t,u,v)≤115(u-u+v-v
), p(u)-p(u)≤110u-u,
f2(t,u,v)-f1(t,u,v)≤110(u-u+v-v
), q(u)-q(u)≤120u-u.
故條件(H1)~(H4)成立. 又因為
2λα-1(μ*+υ*)≈0.282 84lt;(α-1)(1-Mp-Mq)=0.425 00,
定理1的所有條件都滿足, 因此, 適型分數階時滯脈沖微分方程邊值問題(13)至少有一個解. 由于
λα-1(Mf1+Nf1+Mf2+Nf2)+(α-1)(l+l*)≈0.310 70lt;0.5=α-1,
因此, 由定理2可知適型分數階時滯脈沖微分方程邊值問題(13)有唯一解, 由定理3可知適型分數階時滯脈沖微分方程邊值問題(13)具有Ulam-Hyers穩定性.
對任意的t∈[0,1], 設g(t)=t+1, 有
∫1/20s3/2-2(s+1)ds≈1.65≤2(t+1),∫11/2s-123/2-2(s+1)ds≈2.36≤3(t+1),
再設cg=3, 故定理4的所有條件都滿足, 因此適型分數階時滯脈沖微分方程邊值問題(13)具有Ulam-Hyers-Rassias穩定性.
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(責任編輯: 趙立芹)