抽象算子 meaning in English

abstract operator
abstraction operator

Abstract operator logic and its natural deduction system
抽象算子逻辑及其自然演绎系统
By combining the theory of monotone semiflows generated by rfdes and the fixed point theorem of abstract operators , the existence of positive periodic solutions of rfdes is established under the suitable conditions which are useful and easy to verify . nontrivial applications of our results to some periodic ecological systems are also presented
通过建立相应的泛函微分方程产生的单调半流理论，结合抽象算子的不动点定理，给出了泛函微分方程存在正周期解的充分条件，最后用若干周期生态系统的例子来验证所得的结果。
In the second part of this paper ( chapter 4 ) , by constructing the monotone semiflows for retarded functional differential equations with infinite delay , the existence of positive periodic solutions of is given by combining the fixed point theorems of abstract operators . a nontrivial application to periodic ecological systems is presented to illustrate our results
本文的第二部分(第四章)通过对一类无穷时滞周期泛函微分方程构建其单调半流理论，结合抽象算子不动点定理，获得了其正周期解的存在性，并将所得结果应用到生态系统上。