左R-n模的范畴与Hom函子

正合列问题是同调代数的基本问题之一。在Abel范畴的同调代数中,先有核的概念再讨论正合列的概念。但,因n-予加法范畴不具有零对象,欲讨论正合列,对其引进拟核。本文对左R-n模的范畴_R~M_n~l讨论了与拟核相应的正合列;把Hom函子推广到_R~M_n~l上,讨论了它关于拟正合列、弱双积、正向系统的正向极限的不变性。至于对带终对象的范畴的正合列的讨论我们将在中进行。     

范畴C-cr的一些性质

O. In [1], we have shown the cusp catastrophy is the general mathematical model of the treatment based on syndrome differentiation, but the following phenomenons often happen: An old man may die without any local pathological change; A yong man can live well with some serious local pathological changes. In mechanics, there are many similar facts. Then, confronts us a new problem: