Fuzzy半群中的Fuzzy理想

本文先引入Ｆｕｚｚｙ半群中Ｆｕｚｚｙ理想的概念，进而讨论它们的一些代数性质，推广了前人的一些结果。     

Reverse lex ideals

We study reverse lex ideals in a polynomial ring, and compare their properties to those of lex ideals. In particular we provide an analogue of Green's Theorem for reverse lex ideals. We also compare the Betti numbers of strongly stable and square-free strongly stable monomial ideals to those of reverse lex ideals.     

Cellular resolutions of ideals defined by nondegenerate simplicial homomorphisms

In this paper we introduce the class of ordered homomorphism ideals and prove that these ideals admit minimal cellular resolutions constructed as homomorphism complexes. Motivated by work of Dochtermann and Engström, we introduce the class of cointerval simplicial complexes and investigate their combinatorial and topological properties. As a concrete illustration of these structural results, we introduce and study nonnesting monomial ideals, an interesting family of combinatorially defined ideals.     

Constancy regions of mixed multiplier ideals in two‐dimensional local rings with rational singularities

The aim of this paper is to study mixed multiplier ideals associated with a tuple of ideals in a two‐dimensional local ring with a rational singularity. We are interested in the partition of the real positive orthant given by the regions where the mixed multiplier ideals are constant. In particular we reveal which information encoded in a mixed multiplier ideal determines its corresponding jumping wall and we provide an algorithm to compute all the constancy regions, and their corresponding mixed multiplier ideals, in any desired range.     

Betti numbers of mixed product ideals

We compute the Betti numbers of the resolution of a special class of square-free monomial ideals, the ideals of mixed products. Moreover when these ideals are Cohen-Macaulay we calculate their type. Received: 9 March 2008     

Generalized Fuzzy Lie Ideals of Lie Algebras

In this paper we introduce new generalized fuzzy Lie ideals of Lie algebras and study some of their important properties.We characterize these generalized Lie ideals of Lie algebras by their level subsets.Some characterization of the generalized fuzzy Lie ideals of Lie algebras are also established.     

Fuzzy ideals of ternary semigroups

In this paper, we introduce fuzzy ideals of ternary semigroups and study their related properties. Here we define fuzzy left (right, lateral) ideals of ternary semigroups and characterize regular and intra-regular ternary semigroups by using the concept of fuzzy ideals of ternary semigroups.     

BCK—代数的对偶理想

若X是一个集,*是X上的一个二元运算。0是X的一个常元, 满足V~(x,y,z)∈X(K1)(x*y)*(x*y)z*y,(K2)x*(x*y)y,(K3)xx,     

t-Spread strongly stable monomial ideals*

We introduce the concept of t-spread monomials and t-spread strongly stable ideals. These concepts are a natural generalization of strongly stable and squarefree strongly stable ideals. For the study of this class of ideals we use the t-fold stretching operator. It is shown that t-spread strongly stable ideals are componentwise linear. Their height, their graded Betti numbers and their generic initial ideal are determined. We also consider the toric rings whose generators come from t-spread principal Borel ideals.     

Mixed ladder determinantal varieties from two-sided ladders

We study the family of ideals defined by mixed size minors of two-sided ladders of indeterminates. We compute their Gröbner bases with respect to a skew-diagonal monomial order, then we use them to compute the height of the ideals. We show that these ideals correspond to a family of irreducible projective varieties, that we call mixed ladder determinantal varieties. We show that these varieties are arithmetically Cohen-Macaulay, and we characterize the arithmetically Gorenstein ones. Our main result consists in proving that mixed ladder determinantal varieties belong to the same G-biliaison class of a linear variety.     

不分明化PCK—代数

在BCK－代数中定义了不分明化子代数和不分明化理想的概念,讨论了它们的性质及彼此间的关系。     

Tensor powers of symmetric algebras

We prove that over an integral domain a module is projective iff an appropriate tensor power of its symmetric algebra is an integral domain. Further, we show that contracting parts of primary decom­positions of the zero ideal in appropriate tensor powers of a symmetric algebra one obtains families of ideals canonically associated to a mod­ule, having the same radical as Fitting ideals. More precisely, we prove that those new ideals lie between the annihilators of exterior powers of the module and their radicals. An immediate consequence of our re­sults is a way to recover the radicals of Fitting ideals of a module from the symmetric algebra of that module (with its grading forgotten).     

Algebraic properties of classes of path ideals of posets

We consider path ideals associated to special classes of posets such as tree posets and cycles. We express their property of being sequentially Cohen–Macaulay in terms of the underlying poset. Moreover, monomial ideals, which arise in algebraic statistics from the Luce-decomposable model and the ascending model, can be viewed as path ideals of certain posets. We study invariants of these so-called Luce-decomposable monomial ideals and ascending ideals for diamond posets and products of chains. In particular, for these classes of posets, we explicitly compute their Krull dimension, their projective dimension, their Castelnuovo–Mumford regularity and their Betti numbers.     

Asymptotic Ideals (Ideals in the Ring of Colombeau Generalized Constants with Continuous Parametrization)

We study the asymptotics at zero of continuous functions on (0, 1] by means of their asymptotic ideals, i.e., ideals in the ring of continuous functions on (0, 1] satisfying a polynomial growth condition at 0 modulo rapidly decreasing functions at 0. As our main result, we characterize maximal and prime ideals in terms of maximal and prime filters.     

BCH-代数的模糊理想与模糊H-理想

在BCK／BCI／BCC代数中Fuzzy理想被广泛研究，但在BCH-代数中还没有讨论过。在BCH-代数中引人了Fuzzy理想与FuzzyH-理想的概念，并讨论它们的性质。     

BCH-代数的Ω-模糊点理想

引入BCH-代数的Ω-模糊点理想的概念,给出了它的几个实例,研究了它们的一些性质.讨论了Ω-模糊理想与Ω-模糊点理想的关系,获得了Ω-模糊点理想的几个等价描述,研究了Ω-模糊点理想的同态像与同态原像的性质,给出了BCH-代数的Ω-模糊点理想与BCH-代数之积代数的Ω-模糊点理想的关系, 讨论了模糊点理想与Ω-模糊点理想之间的相互构造.     

UNIQUE FACTORIZATION AND BIRTH OF ALMOST PRIMES

ABSTRACT

In studying unique factorization of domains we encountered a property of ideals. Using that we define the notion of almost prime ideals and prove that in Noetherian domains almost prime ideals are primary. We also prove that in a regular domain almost primes are precisely primes. Further, we define strictly nonprime ideals and study some inter relations between almost prime ideals, strictly nonprime ideals and factorization of ideals.     

半群的(∈,∈∨q(λ,μ))-模糊n伪理想与Drazin半群的刻画

给出半群的模糊n伪理想,广义模糊n伪理想,(∈,∈∨q(λ,μ))-模糊n伪理想的定义,同时讨论了(∈,∈∨q(λ,μ))-模糊n伪左理想(右理想,理想)和广义模糊n伪左理想(右理想,理想)的等价刻画.还利用半群的广义模糊子系统来刻画Drazin半群的结构.