GLOBAL ATTRACTIVITY IN A PERIODIC DELAY SINGLE SPECIES MODEL

1.IntroductionGopalsamyandLadajs[1]illtroducedthefollowingdelayLotka-Volterratypesinglespeciespopulationgrowthmodel:wherea,b,ctTarerealconstants,anda>0,c>0,T20.Ifa>0,b<0andc=0,then(1.1)reducestotheLogisticequation.Ifb>0,(l.1)exhibitstheso--calledAlic...     

非线性退缩椭圆型方程组边值问题的非负解

应用上、下解方法建立非线性退缩椭圆型方程组边值问题耦合拟解的存在性定理;通过实际构造非负上下解,证明N=2,f_1=u_2~(1+β),f_2=u_1~(1+α)时非负解存在。