Ext-products and edge-morphisms
نویسندگان
چکیده
منابع مشابه
Ext Groups and Ext Functors
If A and B are Abelian groups, then Hom(A,B) is also an Abelian group under pointwise addition of functions. In this section we will see how Hom gives rise to classes of functors. Let A denote the category of Abelian groups. A covariant functor T : A → A associates to every Abelian group A an Abelian group T (A), and for every homomorphism f : A → B a homomorphism T (f) : T (A)→ T (B), such tha...
متن کاملProducts of Edge-perts
Images represent an important and abundant source of data. Understanding their statistical structure has important applications such as image compression and restoration. In this paper we propose a particular kind of probabilistic model, dubbed the “products of edge-perts model” to describe the structure of wavelet transformed images. We develop a practical denoising algorithm based on a single...
متن کاملEdge Regular Graph Products
A regular nonempty graph Γ is called edge regular, whenever there exists a nonegative integer λΓ, such that any two adjacent vertices of Γ have precisely λΓ common neighbours. An edge regular graph Γ with at least one pair of vertices at distance 2 is called amply regular, whenever there exists a nonegative integer μΓ, such that any two vertices at distance 2 have precisely μΓ common neighbours...
متن کاملEdge-transitive products
This paper concerns finite, edge-transitive direct and strong products, as well as infinite weak Cartesian products. We prove that the direct product of two connected, non-bipartite graphs is edge-transitive if and only if both factors are edgetransitive and at least one is arc-transitive, or one factor is edge-transitive and the other is a complete graph with loops at each vertex. Also, a stro...
متن کاملWreath products for edge detection
Wreath product group based spectral analysis has led to the development of the wreath product transform, a new multiresolution transform closely related to the wavelet transform. In this work, we derive the lter bank implementation of a simple wreath product transform and show that it is in fact, a multiresolution Roberts Cross edge detector. We also derive the relationship between this transfo...
متن کاملذخیره 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: Tohoku Mathematical Journal
سال: 1971
ISSN: 0040-8735
DOI: 10.2748/tmj/1178242546