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![]() Journal of Applied Mathematics and Physics, 2014, 2, 108-114 Published Online April 2014 in SciRes. http://www.scirp.org/journal/jamp http://dx.doi.org/10.4236/jamp.2014.25014 How to cite this paper: Zhou, L.N. and Jiang, W.H. (2014) Positive Solutions for Fractional Differential Equations with Multi-Point Boundary Value Problems. Journal of Applied Mathematics and Physics, 2, 108-114. http://dx.doi.org/10.4236/jamp.2014.25014 Positive Solutions for Fractional Differential Equations with Multi-Point Boundary Value Problems Lina Zhou1, Weihua Jiang2 1College of Mathematics and Information Science, Hebei Normal University, Shijiazhuang, China 2College of Science, Hebei University of Science and Technology, Shijiazhuang , China Email: [email protected], [email protected] Received Novemb er 20 13 Abstract In this paper, a fractional multi-point boundary value problem is considered. By using the fixed point index theory and Krein-Rutman theorem, some results on existence are obtained. Keywords Caputo Fractional Derivative, Fractional Integral, Boundary Value Problem, Fixed Point Index Theory 1. Introduction Fractional differential equations have been of great interest recently. This is due to the intensive development of the theory of fractional calculus itself as well as its applications. Apart from diverse areas of mathematics, frac- tional differential equations arise in rheology, dynamical processes in self similar and porous structures, elec- trical networks, visco-elasticity, chemical physics, and many other branches of science. For details, see [1]-[7]. It should be noted that most of papers and books on fractional calculus are devoted to the solvability of linear initial fractional differential equations on terms of special functions. Recently, there are some papers dealing with the existence and multiplicity of solution to the nonlinear fractional differential equations boundary value problems, see [8]-[14]. Zhao [11] investigated the existence and uniqueness of positive solutions for a local boundary value problem of fractional differential equation. 0()(, ())0 01 (0)() 0,(1)() 0 Dutf tutt u uuu α βξ γη + += << ′′ −= += where α is a real number with 12,0, 1,01 αβγξ η <≤≤≤ ≤≤≤ , 0 D α + is the Caputo’s derivative. Inspired by above work, we will consider the fractional boundary value problem ![]() L. N. Zhou, W. H. Jiang 109 0 3 1 ()(, ())0 01 (0) ()0,(1)()0 m ii i Dutf tutt uuu u α βξγ η + − = += << ′′ −=+ = ∑ (1) where α is a real number with 12, 01, 01,1, 2,,3, iim α βγ <≤≤≤≤≤=− 12 3 01 m ξη ηη − ≤< << <≤ , 0 D α + is the Caputo’s derivative. Let 33 11 (1)(1 ). mm ii i ii βγ ηγβξ −− = = ∆= ++− ∑∑ Now we list some conditions for convenience. (H1) 3 1 (1)(1),1(1) 0 m ii i αβξγ η − = −−>∆ +−> ∑ (H2) : [0,1]f RR ++ ×→ satisfied Carathéodory condition,that is (, )fu⋅ is measurable for each fixed uR + ∈ and (,)ft⋅ is continuous for a.e. [0,1]t∈ . For any 0r> , there existed 1 ( )[0,1]tLΦ∈ such that (, )()f tut≤Φ , where [0, ]ur∈ ; a.e. [0,1]t∈ . (H3) 0,0,(,)lLftuL∀>∃ >< where [0, ]ul∈ ; a.e. [0,1]t∈ . 2. Preliminary For the convenience of readers, we provide some background material in this section. {\bf Definition 2.1[7] The Riemann-Liouville fractional of order α for function y is defined as 1 00 1 ()( )() () t Iy ttsys ds αα α − += − Γ∫ Definition 2.2 [7] The Caputo’s derivative for function y is defined as () 01 0 1 () () () () n t n ys Dytds nts α α α ++− =Γ− − ∫ Lemma 2.1 [14] Let 0 α > , then the fractional differential equation 0()0D ut α += has solutions 21 12 3 (),,1, 2,,,[]1 n ni utcct ctctcRinn α − =+ +++∈==+ Lemma 2.2 [14] Let 0 α > , then for some ,1, 2,,,[]1 i c Rinn α ∈= =+ Lemma 2.3 (Krein-Rutman) [15] Let K be a reproducing cone in a real Banach space X and let :LX X→ be a compact linear operator with ()LKK⊆ . ()rL is the spectral radius of L If () 0rL> , then there exists 1 \ {0}K ϕ ∈ such that 11 ()L rL ϕϕ = . Lemma 2.4 [16] Let X is a Banach space, P be a cone in X and ()PΩ be a bounded open subset in P . Suppose that : ()APPΩ→ is a completely continuous operator. Then the following results hold: (1) If there exists 0\ {0}uP∈ such that 0 ,( ),0u AuuuP λλ ≠+∀∈∂Ω> then the fixed point index ( ,( ),)0iAPPΩ= . (2) If 0 ()P∈Ω and ,( ),1Auu uP λλ ≠∀∈ ∂Ω≥ , then the fixed point index ( ,( ),)1iAPPΩ= . Take [0,1]XC= with norm [0,1] ()max() t xt xt ∈ = , 1 [0,1]YL= with norm 1 10 () () xtxt dt= ∫ . {|()0,[0,1]}KuX utt=∈ ≥∈ Obviously K is a reproducing cone of X . Lemma 2.5 If [0,1],1 2,yC α ∈ <≤ then the unique solution of 0 3 1 ()() 001 (0) ()0,(1)()0 m ii i D utytt uuu u α βξγ η + − = + =<< ′′ −=+ = ∑ is 1 0 ()(, ) (),utGtsys ds= ∫ where ![]() L. N. Zhou, W. H. Jiang , 110 3 11 1 3 21 1 3 12 1 3 1 [1( )] 1()( ) () () 1(1 ) (1 )(), (1)( ) [1( )]1 ()(1 ) ( )(1) (1)( () (,) m ii i m ii i m ii i m i i t ts s tt sss st tt ss t Gts αα αα αα β γη ξ αα βξ ββξ βγη ξ αα β γηβξ β ξ αα βξ βγη α − −− = − −− = − −− = − = +− − −+− Γ ∆Γ −+ −+ +−+−≤≤ ∆Γ −∆Γ +− −+ −+ − ∆Γ∆Γ − −+ +∆Γ = ∑ ∑ ∑ ∑1 12 311 1 3 21 1 1 12 ), 11 ()(1 ) ( )(1) (1)() , () 1(1 ) (1 )(), (1)( ) 11 ()(1 ) ( )(1) (1 i m ii i m ii i ss ts t ts s tss st tt sss ts t ts s α αα α αα αα ξ βξ β αα βξ βγηξ η α βξ ββξ βγηξ η αα βξ β αα − −− −− = − −− = −− − ≤≤ −+ − −+− Γ∆Γ − −+ +−≤≤ ≤ ∆Γ −+ −+ −+−≤≤ ≤ ∆Γ −∆Γ −+ − −+− Γ∆Γ − − + ∑ ∑ 311 3 21 1 )() , () 1(1 ) (1 )(), (1)( ) m jji i ji m jji i ji tss st tt sss ts α αα βξ βγηη η α βξ ββξ βγηηη αα −− − = − −− − = + −≤≤ ≤ ∆Γ −+ −+ −+−≤≤≤ ∆Γ −∆Γ ∑ ∑ Proof: The equation 0 ()() 0D utyt α + += has a unique solution 112 0 1 ()( )() () t uttsysdscc t α α − =− −++ Γ∫ where 12 ,.cc R∈ By 3 1 (0)()0,(1)()0 m ii i uuu u βξγ η − = ′′ −=+ = ∑ , we have 33 1 1 000 11 1[(1)() (1)(1) (1)()] mm iii i ii cIyI yIy αα α βγ ηξβξβξγη −− − ++ + = = = ++−+− ∆ ∑∑ 33 1 20 00 11 1[(1)()( )] mm ii i ii cI yIyIy ααα ββγηβγξ −− − +++ = = =+− ∆ ∑∑ 3 1 1 12 1 0 00 31 0 1 [1( )] 11 ()() ()() ()(1)() ()()( 1) (1) () () () i m ii tt i m ii i tt uttsy sdssy s dssy s ds tsy s ds α αα ηα β γηβξ β ξ αα α βξ βγη α − − −− = −− = +− −+ =−−+−+ − Γ∆Γ∆Γ − −+ +− ∆Γ ∑ ∫ ∫∫ ∑∫ The proof is complete. Lemma 2.6 If (H1) hold, then there exist a constant M such that 2 0( ,)(1),,[0,1]GtsMsts α − ≤ ≤−∈ Proof: Obviously ( ,)0,Gts ≥ ![]() L. N. Zhou, W. H. Jiang 111 3 3 12 1 1 01 1 3 3 22 2 1 1 3 1 [1( )]1(1 ) max( ,)()(1)() ()( 1)() [1 ]1(1 ) (1 )(1 )(1 ) ()(1)() (1 m ii m iii ti m ii m ii i m i i ttt Gtss ss ss s αα α αα α β γηβξ ββξ β ξ γη αα α β γηβξββξβγ αα α βγ − − −− − = ≤≤ = − − −− − = = − = +− −+ −+ ≤−+− +− ∆Γ∆Γ −∆Γ +−+ −+ ≤−+− +− ∆Γ∆Γ −∆Γ + = ∑∑ ∑∑ 3 2 1 ) (1)(1)(1) (1 ) () m ii i s α ηαβξ βγβξ β α − − = +−−++ −+ − ∆Γ ∑∑ Let 33 11 (1 )(1)(1 )(1 ) () mm ii i ii M βγ ηαβξβγβξβ α −− = = ++−−++ −+ =∆Γ ∑∑ .The proof is completed. Define an operator :AK K→ and a linear operator :TX X→ as follows: 1 0 ( )( ,)(,())Au tG tsfsusds= ∫ 1 0 ()(, ) ()TutGts usds= ∫ Then the fixed point \ {0}uK∈ of A is the positive solutions of (1) 3. Main Results In order to obtain our main results, we firstly present and prove some lemmas. Lemma 3.1 If (H1)-(H3) hold, then :AK K→ and :TX X→ are completely continuous. Proof: According to the Lebesgue Dominated Convergence Theorem and Lemma 2.6, we have :AK K→ is uniformly bounded and equicontinuous. It follows from Ascoli-Arzela theorem that : AK K → is com- pletely continuous. By the same method, we can get that :TX X→ is completely continuous also. Lemma3.2 If (H1)-(H2) hold, then () 0rT> ( r is the spectral radius of T ) Proof: Take () 1ut≡ 1 0 3 1 1 12 1 0 00 31 0 1 3 1 ()(, ) () [1( )] 11 ()()(1 ) ()()(1) (1) () () [1( )] 11 ()()(1 i m ii tt i m ii i m ii i Tu tG tsu sds tt ts dss dssds ts ds t tt α αα ηα αα β γηβξ β ξ αα α βξ βγη α βγη ξβξ β αααα α − − −− = −− = − = = +− −+ =− −+−+− Γ∆Γ∆Γ − −+ +− ∆Γ +− −+ =−++ Γ∆Γ∆Γ − ∫ ∑ ∫ ∫∫ ∑∫ ∑ 3 1 3 1 1 (1) ) 1() 11(1): (1) () (1) m ii i m ii i t l α α γη βξ β α αα βξβξ γη α αα − = − = −+ + − ∆Γ −− ≥−+ += Γ +∆Γ∆Γ + ∑ ∑ 22 ()(())(),( ()) nn TutTTutTll Tutl= ≥≥≥ 11 , ()lim0 nn nn n TlrT Tl →∞ ≥ =≥> The proof is completed. By Lemma 2.3, we can get there exists 0\{0}K ϕ ∈ such that 00 ()T rT ϕϕ = ![]() L. N. Zhou, W. H. Jiang , 112 Define 00 [0,1]\[0,1]\ (, )(, ) liminfinf,limsup sup utE u tE f tuf tu ff uu ∞ →∈ →∞ ∈ = = , where [0,1]E⊂ , with () 0mE= ( ()mE is the lebesgue measure of E and the same as follows). Set 1 { |},. () K uKurT ρ ρµ =∈ <= Lemma 3.3 Suppose 0 f µ < ≤∞ , then there exists 0 0 ρ > such that for 0 (0, ] ρρ ∈ , if ,uAu uK ρ ≠∀ ∈∂ ,then ( ,,)0.iAKK ρ = Proof: It follows from 0 f µ < that there exists 0 ε > and 0 0 ρ > such that for a.e. 0 [0,1], 0tu ρ ∈ ≤≤ (, )()f tuu µε ≥+ (2) For 0 0 ρρ <≤ , assume , uAu uK ρ ≠∀ ∈∂ By Lemma 2.4,we need only to prove that 0, ,0u AuuK ρ λϕ λ ≠+∀ ∈∂> where 0 00 \ {0},()KTrT ϕ ϕϕ ∈= . Otherwise, there exists 00 ,0 uK ρ λ ∈∂> such that 0000 u Au λϕ = + (3) Then 00000 ,, uAu u λϕ ≥≥ by (2), we can get that 1 00 0 0( ,)(,())() AuG tsfsusdsTu µε = ≥+ ∫ (4) Considering 0 00 ,u λϕ ≥ we get 00000 ()Au T µε λϕλϕ ≥+ > . This together with (3) means that 0 00 2,u λϕ ≥ by (4) we get 0 00 2Au λϕ ≥ .So 0 00 3u λϕ ≥ . Repeating this process, we get that 0 00 un λϕ ≥ , so we have 0 00 ,.un n λϕ ≥→∞ →∞ This is a contradic- tion. It follows from Lemma 2.4 that 0 ( ,,)0,(0,]iAK K ρ ρρ = ∈ . The proof is completed. Lemma 3.4 Suppose 0f µ ∞ ≤< , then there exists 0 0r> such that ( ,,)1, r iAKK = for each 0 rr> Proof: Let 0 ε > satisfy f µε ∞<− , then there exists 10r> such that 1 (,)(),for ,a.e.[0,1]f tuuurt µε ≤−> ∈ By (H3),there existed 1 ( )[0,1]tLΦ∈ such that (, )() f tut≤Φ , where 1 [0, ]ur∈ ; a.e. [0,1]t∈ . Thus, for all uR + ∈ a.e. [0,1]t∈ (, )()()f tuut µε ≤ −+Φ (5) Since 1 ()rT µ = , 1 () IT µε − − − exists. Let 11 0 0 (, )(),() IC CGtss dsrT µε µε − = Φ=− −− ∫ Take 0 rr> , we will show ,Au u λ ≠ for each ,1 r uK λ ∈∂ ≥ . Otherwise, there exist 00 ,1 r uK λ ∈∂ ≥ , such that 0 00 ,Au u λ = This together with (5), implies 0 0000 ()uuAuTu C λ µε ≤= ≤−+ Then 0 ()() IC Tut µε µε −≤ −− . So we get 0 ()(). CI Tu tK µε µε −− ∈ −− It follows from 11 0 ()() nn n ITT µε µε ∞ −+ = −= − − ∑ and ()TK K⊂ , we get 1 0 () () IC ut T µε µε − ≤− −− . Therefore, we have 00 u rr≤≤ . This is a contradiction. By Lemma 2.4 (2), we get ( ,,)1, r iAKK = for each 0 rr> . The proof is completed. Theorem 3.1 Suppose 0 f µ < ≤∞ and 0f µ ∞ ≤< then (1) has at least one positive solution. Proof: It follows from 0f µ ∞ ≤< and Lemma 3.4 there exists 0r> such that (,, ) 1 r iAKK = . By 0 f µ < <∞ and Lemma 3.3, we can get there exists 0r ρ << such that either there exists uK∈∂ with or (,,)0uAuiA KK ρ = = . In the second case, A has a fixed point uK∈ with ur ρ ≤< by the properties of index. The proof is completed. ![]() L. N. Zhou, W. H. Jiang 113 4. Example Let’s consider the following boundary value problem 3 2 0 ()(, ())001 11 13 (0)() 0,(1)() 0 5454 Dutf tutt uu uu + += << ′′ −=+= (6) where ,[0,1] is a irrational number (, )0,[0,1] is a rational number u tt f tut +∈ =∈ . Corresponding to the problem (1), we have that 31311 ,,,, 24455 αξηβγ = = === . Let {|[0,1] is a rational number}E tt= ∈ , then () 0mE= . Obviously, (H1)-(H3) are satisfied. By simple calcula- tion, we get 0,0ff ∞ =∞= . By Theorem 3.1, we get that (6) has at least one solution. This problem can be not solved by the theorem in [11]. Acknowledgements This work is supported by the Natural Science Foundation of China (11171088), the Natural Youth science Foundation of China (11101118) and the Natural Science Foundation of Hebei Province (A2012205074). References [1] Kilbas, A.A., Srivastava Hari, M. and Trujillo Juan, J. (2006) Theory and Applications of Fractional Differential Equa- tions. North-Holland Mathematics Studied, Vol. 204. Elsevier Science BV, Amsterdam. [2] Oldham, K.B. and Spanier, J. (1974) The Fractional Calculus . Academic Press, New York, London. [3] Ross, B. (1975) The Fractional Calculus and Its Applications. Lecture Notes in Mathematics, Vol. 475, Springer, Ber- lin. [4] Nonnenmacher, T.F. and Metzler, R. (1995) On the Riemann-Liouvile Fractional Calculus and Some Recent Applica- tions. Fractals, 3, 557-566. http://dx.doi.org/10.1142/S0218348X95000497 [5] Tatom, F.B. (1995) The Relationship between Fractional Calculus and Fractals. Fractals, 3, 217-229. http://dx.doi.org/10.1142/S0218348X95000175 [6] Podlubny, I. (1999) Fractional Differential Equations. Mathematics in Science and Engineering, Vol. 198, Aca- demicPress, NewYork/London/Toronto. [7] Samko, S.G., Kilbas, A.A. and Marichev, O.I. (1993) Fractional Integrals and Derivatives. (Theory and Applications). Gordon and Breach, Switzerland. [8] Baleanu, D., Mustafa, O.G. and Agarwal, R.P. (2010) An Existence Result for a Super Linear Fractional Differential Equation. Applied Mathematics Letters, 23, 1129-1132. http://dx.doi.org/10.1016/j.aml.2010.04.049 [9] Baleanu, D., Agarwal, R.P., Mustafa, O.G. and Cosulschi, M. (2011) Asymptotic Integration of Some Nonlinear Dif- ferential Equations with Fractional Time Derivative. Journal of Physics A: Mathematical and Theoretical, 44. http://dx.doi.org/10.1088/1751-8113/44/5/055203 [10] Baleanu, D., Mustafa, O.G. and Aga rwal, R.P. (2010) On the Solution Set for a Class of Sequential Fractional Differ- ential Equations. Journal of Physics A: Mathematical and Theoretical, 43. [11] Zhao, X.K., Chai, C.W. and Ge, W.G. (2011) Positive Solutions for Fractional Four-Point Boundary Value Problems. Communications in Nonlinear Science and Numerical Simulation, 16, 3665-3672. http://dx.doi.org/10.1016/j.cnsns.2011.01.002 [12] Wang, J.H., Xiang, H.J. and Liu, Z.G. (2010) Positive Solution to Nonzero Boundary Value Problem for a Coupled System of Nonlinear Fractional Differential Equations. International Journal of Differential Equations. [13] Ahmad, B. and Nieto, J.J. (2009) Existence Results for a Coupled System of Nonlinear Fractional Differential Equa- tions with Three-Point Boundary Conditions. Computers & Mathematics with Applications, 58, 1838-1843. http://dx.doi.org/10.1016/j.camwa.2009.07.091 [14] Zhang, S.Q. (2006) Positive Solutions for Boundary-Value Problem of Fractional Order. Acta Mathematica Scientia, 36, 1-12. ![]() L. N. Zhou, W. H. Jiang , 114 [15] Guo, D. and Lakshmikantham, V. (1988) Nonlinear Problem in Abstract Cones. Academic Press, San Diego. [16] Webb, J.R.L. and Lan, K. Q. (2006) Eigenvalue Criteria for Existence of Multiple Positive Solutions of Nonlinear Boundary Value Problems of Local and Nonlocal Type. Topological Methods in Nonlinear Analysis, Journal of the Juliusz Schauder Center, 27, 91-115. |








