偶数阶三点边值问题多正解的存在性

The Existence of Mutiple Positive Solutions for Even-order Three Points Boundary Value Problems Systems

利用锥理论和Leggett-Williams不动点定理对偶数阶常微分方程组三点边值问题多个正解的存在性u(2m)(t)=(-1)mf(t,v(t)),0≤t≤1,v(2m)(t)=(-1)mg(t,v(t)),0≤t≤1,u(2i)(0)=u(2i)(1)-αu(2i)(ξ)=0,i=0,1,…,m-1,v(2i)(0)=v(2i)(1)-βv(2i)(η)=0,i=0,1,…,m-1进行了讨论和证明,其中0<ξ,η<1,0<α<1/ξ,0<β<1/η且f,g∈C([0,1]×[0,+∞],[0,+∞]).

For the even-order ordinary differential systems {u^（2m）（t）=（-1）^mf（t,v（t））,0≤t≤1,v^（2m）（t）=（-1）^mg（t,v（t））,0≤t≤1,u^（2i）（0）=u^（2i）（1）-αu^（2i）（ξ）=0,i=0,1…,m-1,v^（2i）（0）=v^（2i）（1）-βv^（2i）（η）=0,i=0,1…,m-1 Where f, g ： [ 0, 1 ] × [ 0, ∞ ） → [ 0, ∞ ） are continuous, growth conditions are imposed on f, g which yield the existence of at least three positive solutions by Leggitt - Williams fixed point theorem.