By virtue of a recent existing fixed point theorem of increasing -concave operator by Zhai and Wang, we consider the existence and uniqueness of positive solutions for a new system of Caputo-type fractional differential equations with Riemann–Stieltjes integral boundary conditions.

中文翻译：

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一个新的分数阶微分方程组正解的存在性和唯一性

通过最近存在的不动点定理 -翟王凹算，我们考虑卡普托型分数微分方程黎曼- Stieltjes积分边界条件的新体制的存在和正解的唯一性。