Extensions relative to a Serre class

نویسندگان

چکیده

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Extensions Relative to a Serre Class

Consider a class C of projective /^-modules, where R is a commutative ring with identity, which satisfies the conditions of (2), namely that C is closed under the operations of direct sum and isomorphism and C contains the zero module. Following (2) a module M is said to have C-cotype n (respectively C-type n) if it has a projective resolution ...-*.?„->•...->.Po->M->0 with /",-eC for i>n (resp...

متن کامل

ON RELATIVE CENTRAL EXTENSIONS AND COVERING PAIRS

Let (G;N) be a pair of groups. In this article, first we con-struct a relative central extension for the pair (G;N) such that specialtypes of covering pair of (G;N) are homomorphic image of it. Second, weshow that every perfect pair admits at least one covering pair. Finally,among extending some properties of perfect groups to perfect pairs, wecharacterize covering pairs of a perfect pair (G;N)...

متن کامل

A Direct Approach to Multi-class Boosting and Extensions

Boosting methods combine a set of moderately accurate weak learners to form a highly accurate predictor. Despite the practical importance of multi-class boosting, it has received far less attention than its binary counterpart. In this work, we propose a fully-corrective multi-class boosting formulation which directly solves the multi-class problem without dividing it into multiple binary classi...

متن کامل

extensions of some polynomial inequalities to the polar derivative

توسیع تعدادی از نامساوی های چند جمله ای در مشتق قطبی

15 صفحه اول

A Hochschild-serre Spectral Sequence for Extensions of Discrete Measured Groupoids Roman Sauer and Andreas Thom

We construct a Hochschild-Serre spectral sequence for L-type cohomology groups of discrete measured groupoids using a blend of tools from homological algebra and ergodic theory. Applications include a theorem about existence of normal amenable subrelations in measured equivalence relations, results about possible stabilizers of measure preserving group actions, and vanishing results or explicit...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Proceedings of the Edinburgh Mathematical Society

سال: 1975

ISSN: 0013-0915,1464-3839

DOI: 10.1017/s0013091500010488