Kohji Yanagawa

activity

19982005

most citedNotes on C-graded modules over an affine semigroup ring K[C]

1 citations · 1 across the 6 of their papers we have counts for

collaborators

7 papers

math.AC2005★ 1 cited

Notes on C-graded modules over an affine semigroup ring K[C]

Kohji Yanagawa

Let $C \subset N^{d}$ be an affine semigroup, and $R = K [C]$ its semigroup ring. This paper is a collection of various results on " $C$ -graded" $R$ -modules, especially, monomial i…

math.AC2005

Castelnuovo-Mumford regularity for complexes and weakly Koszul modules

Kohji Yanagawa

Let A be a noetherian AS regular Koszul quiver algebra (if A is commutative, it is essentially a polynomial ring), and grA the category of finitely generated graded left A-modules.…

math.RA2004

Dualizing complex of the incidence algebra of a finite regular cell complex

Kohji Yanagawa

Let $Σ$ be a finite regular cell complex with $\emptyset \in Σ$ , and regard it as a partially ordered set (poset) by inclusion. Let $R$ be the incidence algebra of the poset $Σ$ ov…

math.AC2004

BGG correspondence and Roemer's theorem on an exterior algebra

Kohji Yanagawa

Let E = K< y_1, ..., y_n > be the exterior algebra. The ``(cohomological) distinguished pairs" of a graded E-module M describe the growth of a minimal graded injective resolution o…

math.AC2003

Derived Category of Squarefree Modules and Local Cohomology with Monomial Ideal Support

Kohji Yanagawa

A "squarefree module" over a polynomial ring $S = k [x_{1}, .., x_{n}]$ is a generalization of a Stanley-Reisner ring, and allows us to apply homological methods to the study of monomia…

math.AC2003

Stanley-Reisner rings, sheaves, and Poincare-Verdier duality

Kohji Yanagawa

Recently, I defined a squarefree module over a polynomial ring $S = k [x_{1}, > ..., x_{n}]$ generalizing the Stanley-Reisner ring $k [Δ] = S / I_{Δ}$ of a simplicial complex $Δ\subset 2^{1,…