摘要：In this paper, we study the positive solutions of a higher-order singular fractional differential system with coupled integral boundary conditions. The conditions for the existence of at least one positive solution are established together with the estimates of the lower and upper bounds of the solution at any instant of time. Our results are based on the method of upper and lower solutions and the Schauder fixed point theorem. In the end, an example is worked out to illustrate our main results.
关键词：positive solutions ; upper and lower solutions ; fractional differential system ; coupled integral boundary conditions ; singular
