摘要: 用Banach壓縮映像原理和Krsnoasel’skii不動點(diǎn)定理證明一類具有p-Laplace算子的分?jǐn)?shù)階脈沖微分方程奇異邊值問題解的唯一性和存在性.
關(guān)鍵詞: 分?jǐn)?shù)階微分方程; 脈沖; 不動點(diǎn)定理; 奇異邊值問題; p-Laplace算子
中圖分類號: O175.8" 文獻(xiàn)標(biāo)志碼: A" 文章編號: 1671-5489(2024)04-0842-09
Solutions of Singular Boundary Value Problems for FractionalImpulsive Differential Equations with p-Laplacian Operator
ZHAO Tian1, HU Weimin1,2, LIU Yuanbin3
(1. School of Mathematics and Statistics, Yili Normal University, Yining 835000,Xinjiang Uygur Autonomous Region, China;
2. Institute of Applied Mathematics, Yili Normal University, Yining 835000, Xinjiang Uygur Autonomous Region," China;
3. School of Mathematics and Physics, Xinjiang Institute of Engineering, Urumqi 830023, China)
Abstract: We proved" the uniqueness and existence of solutions for a class of singular boundary value problems of fractional impulsive differential
equations with p-Laplacian operators by using Banach contraction mapping principle and Krsnoasel’skii fixed point theorem.
Keywords: fractional differential equation; impulse; fixed point theorem; singular boundary value problem; p-Laplacian operator
0 引 言
分?jǐn)?shù)階微分方程廣泛應(yīng)用于空氣動力學(xué)、 復(fù)雜介質(zhì)電動力學(xué)、 聚合物流變學(xué)、 實(shí)驗(yàn)數(shù)據(jù)的擬合等領(lǐng)域, 目前, 關(guān)于分?jǐn)?shù)階微分方程邊值問題解的存在性和唯一性研究已有很多結(jié)果[1-14]. 脈沖微分方程在物理學(xué)、 社會學(xué)和信號處理建模中具有重要作用[1-6], 它可以描述模型在某些時(shí)刻發(fā)生變化的狀態(tài), 不能由經(jīng)典的微分方程建模表示. 關(guān)于分?jǐn)?shù)階脈沖微分方程奇異邊值問題的研究已得到廣泛關(guān)注[7\|8]. 近年來, 具p-Laplace算子的分?jǐn)?shù)階微分方程的數(shù)學(xué)模型在多孔介質(zhì)中的湍流過濾、 血液流動、 流變學(xué)和材料科學(xué)中應(yīng)用廣泛, 因此研究具p-Laplace算子的分?jǐn)?shù)階微分方程邊值問題備受關(guān)注[9-14].
文獻(xiàn)[1]研究了分?jǐn)?shù)階脈沖微分方程邊值問題
Dβ0+φp(Dβ0+u(t))=f(t,u(t)), t∈J′,
Δu(tk)=Ik(u(tk)), Δφp(Dα0+u(tk))=bk, k=1,2,…,m,u(0)=u0, Dα0+u(0)=u1
解的存在性, 其中0lt;α,β≤1, 1lt;α+β≤2, 0=t0lt;t1lt;…lt;tklt;…lt;tmlt;tm+1=1, J′=[0,1]\{t1,t2,…,tm}, f∈C([0,1]×瘙綆,瘙綆), u0,u1∈瘙綆, bk∈瘙綆, k=1,2,…,m,
Ik∈C(瘙綆,瘙綆). 文獻(xiàn)[2]用Schauder不動點(diǎn)定理、 不動點(diǎn)指數(shù)定理研究了分?jǐn)?shù)階脈沖微分方程積分邊值問題
-Dα0+u(t)=λa(t)f(t,u,u′), t∈(0,1)\{tk}mk=1,Δu(tk)=Ik(u(tk)), t=tk,
u(0)=u′(0)=…=u(n-2)(0), u′(1)=∫10u(s)dH(s)
的解, 其中n-1lt;α≤n. Dα0+是Riemann-Liouville分?jǐn)?shù)階導(dǎo)數(shù), a(t)∈C((0,1),[0,+∞)), f∈C([0,1]×[0,+∞),[0,+∞)), Ik∈C(瘙綆+,瘙綆+).
文獻(xiàn)[8]研究了分?jǐn)?shù)階微分方程奇異邊值問題
Dα0+u(t)=f(t,u(t)), 0lt;tlt;1,u(0)=u′(t)=u″(t)=u″(1)=0
正解的唯一性, 其中3lt;α≤4, Dα0+為標(biāo)準(zhǔn)的Riemann-Liouville分?jǐn)?shù)階微分, f: (0,1]×[0,+∞)→[0,+∞), f在t=0處奇異.
目前, 對具p-Laplace算子的分?jǐn)?shù)階微分方程邊值問題的研究已有很多結(jié)果, 但對具p-Laplace算子的分?jǐn)?shù)階脈沖微分方程奇異邊值問題的研究報(bào)道較少, 基于此, 本文主要研
究具p-Laplace算子的分?jǐn)?shù)階脈沖微分方程奇異邊值問題
CDβ0+φ(CDα0+u(t))=λf(t,u(t),u′(t)), t∈J′, λgt;0,
Δu(tk)=Ik(u(tk)), Δu′(tk)=Qk(u(tk),u′(tk)), k=1,2,…,m,
u(0)=u0, u(1)=u1, CDα0+u(0)=0(1)
解的存在性, 其中: CDα0+,CDβ0+為標(biāo)準(zhǔn)的Caputo分?jǐn)?shù)階導(dǎo)數(shù), 0lt;β≤1lt;α≤2, 且β+1lt;α; 0=t0lt;t
1lt;…lt;tklt;…lt;tmlt;tm+1=1, J′=[0,1]\{t1,t2,…,tm}; f∈C([0,1]×瘙綆2,瘙綆), 非線性函數(shù)f可能在t=0處具有奇性;
Ik(u)∈C(瘙綆,瘙綆), Qk(u,u′)∈C(瘙綆2,瘙綆), Δu=u(t+k)-u(t-k), Δu′=u′(t+k)-u′(t-k), Δu(t+k),Δu(t-k)和Δu′(t+k),Δu′(t-
k)分別為Δu(tk)和Δu′(tk)在t=tk處的左右極限; φp(s)=sp-2s, pgt;1, (φp)-1(s)=φq(s), 且1/p+1/q=1.
1 預(yù)備知識
為討論方程解的存在性和唯一性, 引入以下空間: 令J=[0,1], 0=t0lt;t1lt;t2lt;…lt;tmlt;tm+1=1, J0=[t0,t1], …, J
m=(tm,tm+1], PC(J,瘙綆)={u: J→瘙綆u∈C(Jk), k=0,1,…,m且u(t+k)存在}, 其范數(shù)為‖u‖PC=supt∈Ju(t), 并有PC′(J,瘙綆)={u: J→瘙綆u∈C(Jk), k=0,1,…,m且u′(t+k)存在}, 其范數(shù)為
‖u‖PC′=supt∈Ju(t)+supt∈Ju′(t),
顯然PC(J,瘙綆)與PC′(J,瘙綆)為Banach空間.
定義1[7] 函數(shù)f :[0,+∞)→瘙綆的αgt;0階積分定義為
Iα0+f(t)=1Γ(α)∫t0(t-s)α-1f(s)ds,
其中右邊是在[0,+∞)上逐點(diǎn)定義的.
定義2[7] 函數(shù)f: [0,+∞)→瘙綆的αgt;0階Caputo微分定義為
CDα0+f(t)=1Γ(n-α)∫t0(t-s)n-α-1f(n)(s)ds,
其中n=[α]+1, 右邊是在[0,+∞)上逐點(diǎn)定義的.
定理1(壓縮映像原理)[7] 設(shè)(X,d)為非空完備度量空間, T: X→X為X上的壓縮映射, 存在qlt;1, 使得x,y∈X, 都有
d(Tx,Ty)lt;qd(x,y), 則存在唯一的ξ∈X, 使得Tξ=ξ.
定理2(Krsnoasel’skii不動點(diǎn)定理)[7] 令M是Banach空間X中的非空閉凸子集, 并且A,B為算子, 使得:
1) 對x,y∈M, Ax+By∈M;2) A為全連續(xù)算子;3) B為壓縮映射.
則存在z∈M, 使得z=Az+Bz.
引理1(Hlder不等式)[7] 假設(shè)γ,δ≥1, 滿足1/γ+1/δ=1, 若a∈Lγ(J), b∈Lδ(J
)對于1≤δ≤∞, ab∈L1(J), 則有‖ab‖L1(J)≤‖a‖Lγ(J)‖b‖Lδ(J).
引理2[2] 若αgt;0, 則有:
1) Iα0+(CDα0+u(t))=u(t)+c0+c1t+…+cn-1tn-1;
2) CDα0+(Iα0+u(t))=u(t).
其中ci∈瘙綆, i=0,1,…,n-1, n=[α]+1.
引理3[4] 對p-Laplace算子φp(s)=sp-2s(pgt;1), 下列結(jié)論成立:
1) 如果1lt;plt;2, uvgt;0, u,v≥rgt;0, 則有
φp(u)-φp(v)≤(p-1)rp-2u-v;
2) 如果pgt;2, u,vlt;R, 則有
φp(u)-φp(v)≤(p-1)Rp-2u-v.
引理4 對給定的函數(shù)y∈C[0,1], u(t)是如下分?jǐn)?shù)階脈沖微分方程積分邊值問題
CDβ0+φ(CDα0+u(t))=y(t), t∈J, λgt;0,
Δu(tk)=Ik(u(tk)), Δu′(tk)=Qk(u(tk),u′(tk)), k=1,2,…,m,
u(0)=u0, u(1)=u1, CDα0+u(0)=0(2)
的解, 當(dāng)且僅當(dāng)有如下形式:
u(t)=∫t0(t-s)α-1Γ(α)φq∫s0(s-τ)β-1Γ(β)y(τ)dτds-c1-c2t, t∈J0,
∫ttk(t-s)α-1Γ(α)φq∫s0(s-τ)β-1Γ(β)y(τ)dτds+∑ki=1∫titi-1(ti-s)α-1Γ(α)φq∫s0(s-τ)β-1Γ(β)y(τ)dτds+
∑ki=1t-tkΓ(α-1)∫titi-1(ti-s)α-2φq∫
s0(s-τ)β-1Γ(β)y(τ)dτds+" ∑k-1i=1tk-tiΓ(α-1)
∫titi-1(ti-s)α-2φq∫s0(s-τ)β-1Γ(β)y(τ)dτds+
∑ki=1Ii(u(ti))+∑ki=1(t-tk)Qi(u,u′)+∑k-1i=1(tk-ti)Qi(u,u′)-c1-c2t, t∈Jk,(3)
其中c1=-u0,
c2=∑m+1i=1∫titi-1(ti-s)α-1Γ(α)φq∫s0
(s-τ)β-1Γ(β)y(τ)dτds+∑mi=11-tmΓ(α)∫ti
ti-1(ti-s)α-1φq∫s0(s-τ)β-1Γ(β)y(τ)dτds
+∑m-1i=1tm-tiΓ(α)∫titi-1(ti-s)α-1φq∫s0(s-τ)β-1Γ(β)y(τ)dτds+∑mi=1Ii(u(ti))+∑mi=1(1-t
m)Qi(u,u′)+∑m-1i=1(tm-ti)Qi(u,u′)+u0-u1.
證明: 設(shè)u(t)為問題(1)的解, 當(dāng)t∈J0=[0,t1]時(shí), 由引理2中1)可得
φp(CDβ0+u(t))=Iβ0+y(t)-c0=1Γ(β)∫t0(t-s)β-1y(s)ds-c0,
由邊值條件CDα0+u(0)=0得c0=0, 因此
φp(CDβ0+u(t))=1Γ(β)∫t0(t-s)β-1y(s)ds.(4)
對式(4)兩邊取φ-1p, 再結(jié)合引理2可得
u(t)=1Γ(α)∫t0(t-s)α-1φq1Γ(β)∫s0(s-τ)β-1y(τ)dτds-c1-c2t,
從而當(dāng)t∈J0=[0,t1]時(shí), 有
u′(t)=1Γ(α-1)∫t0(t-s)α-2φq1Γ(β)∫s0(s-τ)β-1y(τ)dτds-c2,
若t∈J1=(0,t1], 則有
u(t)=1Γ(α)∫tt1(t-s)α-1φq1Γ(β)∫s0(s-τ)β-1y(τ)dτ
ds-d1-d2(t-t1),
u′(t)=1Γ(α-1)∫tt1(t-s)α-2φq1Γ(β)∫s0(s-τ)β-1y(τ)dτds-d2,
其中d1,d2∈瘙綆, 從而可得
u(t-1)=1Γ(α)∫t10(t1-s)α-1φq1Γ(β)∫s0(s-τ)β-
1y(τ)dτds-c1-c2t1," u(t+1)=-d1,
u′(t-1)=1Γ(α-1)∫t10(t1-s)α-2φq1Γ(β)∫s0(s-τ)β
-1y(τ)dτds-c2," u′(t+1)=-d2.
由于Δu(tk)=Ik(u(tk)), Δu′(tk)=Qk(u(tk),u′(tk)),
-d1=1Γ(α)∫t10(t1-s)α-1φq1Γ(β)∫s0(s-τ)β-1y(
τ)dτds-c1-c2t1+I1(u(t1)),
-d2=1Γ(α-1)∫t10(t1-s)α-2φq1Γ(β)∫s0(s-τ)β-1
y(τ)dτds-c2+Q1(u(t1),u′(t1)),
則當(dāng)t∈J1=(t1,t2]時(shí), 有
u(t)= "1Γ(α)∫tt1(t-s)α-1φq1Γ(β)∫s0(s-τ)β-1y(τ)dτds+ "1Γ(α)∫t10(t1-s)α-1φq1Γ(β)∫s0(s-τ)β-1y(τ)dτds+ "t-t1Γ(α-1)∫t10(t1-s)α-2φq1Γ(β)∫s0(s-τ)β-1
y(τ)dτds+ "I1(u(t1))+(t-t1)Q1(u(t1),u′(t1))-c1-c2t.
利用數(shù)學(xué)歸納法, 當(dāng)t∈Jk=(tk,tk+1]時(shí), 有
u(t)= "1Γ(α)∫ttk(t-s)α-1φq1Γ(β)∫s0(s-τ)β-1y(τ)dτds
+ "1Γ(α)∑ki=1∫titi-1(ti-s)α-1φq1Γ(β)
∫s0(s-τ)β-1y(τ)dτds+ "∑ki=1t-tkΓ(α-1)∫t
iti-1(ti-s)α-2φq1Γ(β)∫s0(s-τ)β-1y(τ)dτds
+ "∑k-1i=1tk-tiΓ(α-1)∫titi-1(ti-s)α-2φq1Γ(β)∫s0(s-τ)β-1y(τ)dτds+∑ki=1Ii(u(ti))+ "∑ki=1(t-t
i)Qi(u(ti),u′(ti))+∑k-1i=1(tk-ti)Qi(u(ti),u′(ti))-c1-c2t.
由邊值條件u(0)=u0, u(1)=u1可得式(3); 反之, 若u(t)為式(3)的形式, 由引理2中2)可得u(t)為邊值問題(2)的解.
2 主要結(jié)果
定義算子T: PC′(J,瘙綆)→PC′(J,瘙綆)為
(Tu)(t)= "1Γ(α)∫ttk(t-s)α-1φq1Γ(β)∫s0(s-τ)β-1λf(
τ,u,u′)dτds+ "1Γ(α)∑ki=1∫ti
ti-1(ti-s)α-1φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds
+ "∑ki=1t-tkΓ(α-1)∫titi-1(ti-s)α-2φq1Γ(β
)∫s0(s-τ)β-1λf(τ,u,u′)dτds+ "∑k-1i=1tk-tiΓ(α-1)
∫titi-1(ti-s)α-2φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds+
∑ki=1Ii(u(ti))+ "∑ki=1(t-ti)Qi(u(ti),u′(ti))+∑k-1i=1(tk-ti)Qi(u(ti),u′(ti))-c1-c2t,
(Tu)′(t)= "1Γ(α-1)∫ttk(t-s)α-2φq1Γ(β)∫s0(s-τ)β-
1λf(τ,u,u′)dτds+ "∑ki=11Γ(α-1)∫ti
ti-1(ti-s)α-2φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds
+ "∑ki=1Qi(u(ti),u′(ti))-c2,
其中c1=-u0,
c2= "1Γ(α)∑m+1i=1∫titi-1(ti-s)α-1φq1Γ(
β)∫s0(s-τ)β-1λf(τ,u,u′)dτds+ "∑mi=11-tmΓ(α-1)∫t
iti-1(ti-s)α-2φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds
+ "∑m-1i=1tm-tiΓ(α-1)∫titi-1(ti-s)α-2φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds+∑mi=1Ii(u(ti))+ "∑mi=1(1-t
m)Qi(u(ti),u′(ti))+∑m-1i=1(tm-ti)Qi(u(ti),u′(ti))+u0-u1.
假設(shè):
(H1) 存在正數(shù)N及非負(fù)值函數(shù)a(t),b(t)∈C[0,1], 使得
f(t,u,u′)-f(t,v,v′)≤a(t)u-v+b(t)u′-v′,
并且A=sup0≤t≤1a(t), B=sup0≤t≤1b(t),
N1/(q-1)=sup(t,u,u′)∈[0,1]×[0,r]×[-r,r]f(t,u,u′);
(H2) 存在正數(shù)L1,L2,L3,LI,LQ, x,y∈瘙綆, x′,y′∈瘙綆, 使得
Ik(x)-Ik(y)≤L1x-y," Ik(·)≤LI,
Qk(x,x′)-Qk(y,y′)≤L2x-y+L3x′-y′," Qk(·,·)≤LQ;
(H3) 存在μ∈L1/σ(J,瘙綆), σ∈(0,α-1), 使得對(t,x,x′)∈(J×瘙綆×瘙綆), 有f(t,x,x′)≤μ(t)成立, 并且有
ρ=2mL1+(4m-2)LQ+u0+u1lt;1.(5)
定理3 假設(shè)1lt;plt;2, 條件(H1)~(H3)成立, f∈C(J×瘙綆×瘙綆), 則算子T: PC′→PC′為全連續(xù)算子.
證明: 由f,Ii,Qi的連續(xù)性可知T是連續(xù)的, 這里不妨設(shè)Ω為PC′(J,瘙綆)上的有界子集, 根據(jù)p-Laplace算子的定義和性質(zhì)并結(jié)合條件(H1), 可得
c1≤u0,
c2≤ "1Γ(α)∑m+1i=1∫titi-1(ti-s)α-1φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds
+ "∑mi=1∫titi-1(ti-s)α-2Γ(α-1)φq1Γ(
β)∫s0(s-τ)β-1λf(τ,u,u′)dτds+ "∑m-1i=1∫titi-1
(ti-s)α-2Γ(α-1)φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds+∑mi=1Ii(u(ti))+ "∑mi=1Qi(u(ti),u′(ti))+∑m-1i=1
Qi(u(ti),u′(ti))+u0+u1,
從而可得
(Tu)(t)= "1Γ(α)∫ttk(t-s)α-1φq1Γ(β)∫s0(s-τ)
β-1λf(τ,u,u′)dτds+ "1Γ(α)∑ki=1∫ti
ti-1(ti-s)α-1φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds
+ "∑ki=1∫titi-1(ti-s)α-1Γ(α-1)φq1Γ(
β)∫s0(s-τ)β-1λf(τ,u,u′)dτds+ "∑k-1i=1∫titi-1
(ti-s)α-2Γ(α-1)φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds+∑ki=1Ii(u(ti))+ "∑ki=1Qi(u(ti),u′(ti))+∑k-1i=1
Qi(u(ti),u′(ti))+c1+c2≤ "N2m+2Γ(α+1)+4m-2
Γ(α)λΓ(β+1)q-1+2mL1+2(2m-1)LQ+2u0+u1∶=L1,
(Tu)′(t)≤ "∫ttk(t-s)α-2Γ(α-1)φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds+ "∑ki=1∫titi-1(ti
-s)α-2Γ(α-1)φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds
+ "∑ki=1Qi(u(ti),u′(ti))+c2≤ "NλΓ(β+1)q-1m+1Γ(α)+mL1+(3m-1)LQ+u0+u1∶=L2,
于是有(Tu)(t)+(Tu)′(t)≤L1+L2∶=L, 即算子T一致有界.
另一方面, 對t1,t2∈Jk(k=1,2,…,m), 不妨設(shè)t1≤t2, 可得
(Tu)(t2)-(Tu)(t1)≤1Γ(α)∫t2tk(t
2-s)α-1φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds
-"""" 1Γ(α)∫t1tk(t1-s)α-1φq1Γ(β)∫s0(s-τ)β
-1λf(τ,u,u′)dτds+"""" ∑ki=1t2-tkΓ(α-1)
∫titi-1(ti-s)α-2φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτd
s-"""" ∑ki=1t1-tkΓ(α-1)∫titi-1(ti-s)α-2φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds+"""" ∑ki=1(t2-tk)Qi(u(ti),u′(ti))-∑
ki=1(t1-tk)Qi(u(ti),u′(ti))+(t2-t1)c2≤
NΓ(α+1)λΓ(β+1)q-1((t2-tk)α-(t1-tk)α)+"""" NΓ(α)λΓ(β+1)q-1+mLQ+c2(t2-t1),
當(dāng)t2→t1時(shí), 有(Tu)(t2)-(Tu)(t1)→0,
(Tu)′(t2)-(Tu)′(t1)≤1Γ(α-1)∫t2tk
(t2-s)α-2φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds
-1Γ(α-1)∫t1tk(t1-s)α-2φq1Γ(β)∫s0(s-τ)β
-1λf(τ,u,u′)dτds≤NΓ(α)λΓ(β+1)
q-1((t2-tk)α-(t1-tk)α),
當(dāng)t1→t2時(shí), 有(Tu)′(t2)-(Tu)′(t1)→0.
因此對εgt;0, 總存在不依賴于t1,t2的δ=δ(ε)gt;0, 使得當(dāng)t2-t1lt;δ時(shí), 有‖(Tu)(t2)-(Tu)(t1)‖lt;ε, 從而算子T在[
0,1]上等度連續(xù), 由Arzela-Ascoli定理知, T: PC′→PC′為全連續(xù)算子.
定理4 假設(shè)1lt;plt;2, 條件(H1)~(H3)成立, 則邊值問題(1)至少存在一個(gè)解.
證明: 選取
rgt;M‖μ‖q-1Lλ/σ2m+2Γ(α+1)+4m-2Γ(α)+2mLI+(4m-2)
LQ+u0+u1,
其中M=1Γ(β)1-σβ-σ1-σq-1.
令Br={u∈PC′(J,瘙綆)‖u‖≤r}, 定義算子P,Q為
(Pu)(t)= "1Γ(α)∫ttk(t-s)α-1φq1Γ(β)∫s0(s-τ)β-1λf(
τ,u,u′)dτds+ "1Γ(α)∑ki=1∫ti
ti-1(ti-s)α-1φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds
+ "∑ki=1t-tkΓ(α-1)∫titi-1(ti-s)α-2φq1Γ(β
)∫s0(s-τ)β-1λf(τ,u,u′)dτds+ "∑k-1i=1tk-tiΓ(α-1)
∫titi-1(ti-s)α-2φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτd
s+ "∑mi=11-tmΓ(α-1)∫titi-1(ti-s)α-2φq1Γ(β
)∫s0(s-τ)β-1λf(τ,u,u′)dτds+ "∑m-1i=1tm-tiΓ(α-1)
∫titi-1(ti-s)α-2φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτds,
(Qu)(t)=∑ki=1Ii(u(ti))+∑ki=1(t-ti)Qi(u(ti),u′(ti))+∑k-1i=1(tk
-ti)Qi(u(ti),u′(ti))-∑mi=1tIi(u(ti))-∑mi=1t(1
-tm)Qi(u(ti),u′(ti))+∑m-1i=1t(tm-ti)Qi(u(ti),u′(ti))+(1-t)u0+u1t,
于是對t∈J, u,v∈Br, 再結(jié)合條件(H3)和引理1, 可得
φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτ
≤φqλΓ(β)∫s0(s-τ)(β-1)/(1-σ)dτ1-σ∫s
0μ(τ)1/σdτ)σ≤M‖μ‖q-1L1/σ,
從而
‖Pu+Qv‖≤M‖μ‖q-1Lλ/σ2m+2Γ(α+1)+4m-2Γ(α)
+2mLI+(4m-2)LQ+u0+u1.
因此Pu+Qv∈Br, 由定理2和定理3知, 邊值問題(1)至少存在一個(gè)解.
定理5 假設(shè)1lt;plt;2, 若條件(H1),(H2)成立, 且滿足
ρ=N(q-1)1Γ(β+1)q-12m+2Γ(α+1)+4m-2Γ(α)+2mLI+(4m-2)(L2+L3)lt;1,(6)
則邊值問題(1)有唯一解.
證明: 設(shè)Br為PC′的有界子集, 令Br={u∈PC′‖u‖≤r}, 由式(6)可選取r為如下形式:
rgt;NλΓ(β+1)q-12m+2Γ(α+1)+5m-1Γ(α)+3mLI+(
7m-3)LQ+3u0+2u1.
定義算子T: Br→PC′, 由定理 3可知Tu一致有界, 即有(Tu)(t)+(Tu)′(t)≤L1+L2lt;r, 因此得‖(Tu)‖lt;r, 即T(Br)Br, 往證T是壓縮算子.
對于t∈J, u,v∈Br, 有
(Tu)(t)-(Tv)(t)≤1Γ(α)∫ttk(t-s)α-1
φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτ-
φq1Γ(β)∫s0(s-τ)β-1λf(τ,v,v′)dτds+"""" 1Γ(α)∑
ki=1∫titi-1(ti-s)α-1φq1Γ(β)∫s0(s-τ)β
-1λf(τ,u,u′)dτ-"""" φq1Γ(β)∫s0(s-τ)β
-1λf(τ,v,v′)dτ ds+"""" ∑ki=1t-tkΓ(α-1)∫titi-1(ti-s)
α-2φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτ
-"""" φq1Γ(β)∫s0(s-τ)β-1λf(τ,v,v′)dτds+
∑k-1i=1tk-tiΓ(α-1)∫titi-1(ti-s)α-2φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτ-"""" φq1Γ(β)∫s0(s-τ)β
-1λf(τ,v,v′)dτds+∑ki=1Ii(u)-Ii(v)+
∑ki=1(t-ti)Qi(u,u′)-Qi(v,v′)+∑k-1i=1(tk-ti)Qi(u,u′)-Qi(
v,v′)+"" ""1Γ(α)∑mi=1∫titi-1(ti-s)α-1φq1Γ(β)
∫s0(s-τ)β-1λf(τ,u,u′)dτ-"""" φq1Γ(β)∫s0(s-τ)β
-1λf(τ,v,v′)dτds+"""" ∑mi=11-tmΓ(α-1)∫t
iti-1(ti-s)α-2φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτ-
φq1Γ(β)∫s0(s-τ)β-1λf(τ,v,v′)dτds
+"""" ∑m-1i=1tm-tiΓ(α-1)∫titi-1(ti-s)α-2φq1Γ(β)∫s0(s-τ)β-1λf(τ,u,u′)dτ-"""" φq1Γ(β)∫s0(s-τ)β
-1λf(τ,v,v′)dτds+∑ki=1Ii(u)-Ii(v)+
∑mi=1Ii(u)-Ii(v)+∑mi=1(1-tm)Qi(u,u′)-Qi(v,v′)
+"""" ∑m-1i=1(tm-ti)Qi(u,u′)-Qi(v,v′)+∑mi=1Qi(u,u′)-Qi(v,v′)
≤"""" N(q-1)λΓ(β+1)q-12m+2Γ(α+1)+4m-2Γ(α)+2mL+(4m-2)(L2+L3)‖u-v‖.
由式(6)可得T為壓縮映射, 由壓縮映射原理知, 具p-Laplace算子的分?jǐn)?shù)階脈沖微分方程奇異邊值問題(1)在PC′有唯一解.
3 應(yīng)用實(shí)例
考慮如下奇異邊值問題:
CD1/20+φp(CD3/20+u(t))=t-1/3u(t)16+u′(t)16, t∈(0,1),
Δu=u(1/2)20+u(1/2), Δu=u(1/2)20+u(1/2)+u′(1/2)20+u′(1/2),u(0)=0, u(1)=1, CD3/20+u(0)=0,(7)
其中β=12, α=32, p=43,λ=m=1, f(t,u,u′)=t-1/3u(t)16+u′(t)16, 則有
ρ= "N(q-1)1Γ(β+1)q-12m+2Γ(α+1)+4m-2Γ(α)
+2mLI+(4m-2)(L2+L3)= "224512π2+1120≈0.594 3lt;1,
由定理5知, 邊值問題(7)有唯一解.
參考文獻(xiàn)
[1] LIU Z, LU L, SZNT I. Existence of Solutions for Fractional Impulsive Diff
erential Equations with p-Laplacian Operator [J]. Acta Mathematica Hungarica, 2013, 141(3): 203-219.
[2] ZHAO K H. Impulsive Integral Boundary Value Problems
of the Higher-Order Fractional Differential Equation with Eigenvalue Arguments [J/OL]. Advances in Difference Equations, (2015-12-23)[2023\|09\|20]. https://doi.org/10.1186/s13662-015-0725-y.
[3] ZHOU W X, LIU X, ZHANG J G. Some New Existence and Uniqueness Results of Solutions to Semilinear Impulsive Fractional Integro-Diffe
rential Equations [J/OL]. Advances in Difference Equations, (2015-02-11)[2023\|09\|20]. https://doi.org/10.1186/s13662-015-0372-3.
[4] BAI Z B, DONG X Y, YIN C. Existence Results for Impulsive Nonlinear Fracti
onal Differential Equation with Mixed Boundary Conditions [J/OL]. Boundary Value Problems, (2016-03-15)\. https://doi.org/10.1186/s13661-016-0573-z.
[5] WANG X C, SHU X B. The Existence of Positive Solutions for Impulsive Fract
ional Differential Equations with Boundary Value Conditions [J]. Journal of Mathematics, 2017, 37(2): 271-282.
[6] MAHMUDOV N, UNUL S. On Existence of BVP’s for Impulsive Fractional Diffe
rential Equations [J/OL]. Advances in Difference Equations, (2017-01-13)[2023\|09\|20]. https://doi.org/10.1186/s13662-016-1063-4.
[7] ZHOU W X, LIU X. Uniqueness on Positive Solutions for Boundary Value Proble
m of Singular Fractional Differential Equations [J]. Chinese Journal of Engineering Mathematics, 2014, 31(2): 300-309.
[8] 張彩玲. 一類奇異分?jǐn)?shù)階微分方程邊值問題正解的存在性 [J]. 吉林大學(xué)學(xué)報(bào)(理學(xué)版), 2022, 60(3): 487-493. (
ZHANG C L. Existence of Positive Solutions for Boundary Value Problems of a Class of Singular Fractional Differential Equatons [J]. Journal of Jilin Univers
ity (Science Edition), 2022, 60(3): 487-493.)
[9] CHEN T Y, LIU W B, HU Z G. A Boundary Value Problem for Fractional Diff
erential Equation with p-Laplacian Operator at Resonance [J]. Nonlinear Analysis, 2012, 75(6): 3210-3217.
[10] FEN F T, KARACA I Y, OZEN O B. Positive Solu
tions of Boundary Value Problems for p-Laplacian Fractional Differential Equations [J]. Filomat, 2017, 31(5): 1265-1277.
[11] TAN J J, CHENG C Z. Existence of Solutions of Boundary Value Problems for
Fractional Differential Equations with p-Laplacian Operator in Banach Spaces [J]. Numerical Functional Analysis and Optimization, 2017, 38(6): 738-753.
[12] LIU X P, JIA M, GE W G. The Method of Lower and Upper Solutions for Mi
xed Fractional Four-Point Boundary Value Problem with p-Laplacian Operator [J]. Applied Mathematics Letters, 2017, 65: 56-62.
[13] DONG X Y, BAI Z B, ZHANG S Q. Positive Solutions to Boundary Value Pro
blems of p-Laplacian with Fractional Derivative [J/OL]. Boundary Value Problems, (2017-01-03)[2023\|09\|20]. https://doi.org/10.1186/s13661-016-0735-z.
[14] 李小平. 一類帶p-Laplace算子的Caputo分?jǐn)?shù)階導(dǎo)數(shù)邊值問題解的存在性 [J]. 吉林大學(xué)學(xué)報(bào)(理學(xué)版), 2022, 60(3): 507-513. (
LI X P. Existence of Solutions for a Class of Caputo Fractional Derivative Boundary Value Problems with p-Laplace Operators [J]. Journal of Jilin Uni
versity (Science Edition), 2022, 60(3): 507-513.)
(責(zé)任編輯: 趙立芹)