分配伪补格的主理想

本文给出了分配伪补格 ( L;∧ ,∨ ,* ,0 ,1 )中的主理想 I=( d]成为同余理想的充分必要条件 .当 L是局部有限时 (即 d∈ S( L) ,Fd={x|x* * =d}有限 ) ,对骨架 S( L)中的每个元素 d,我们找到了以 I=( d]为核心的最小同余关系 ,利用以上结果我们得到一个 Stone代数是布尔代数的一些等价条件 .     

分配伪补格的主理想

本给出了分配伪补格（Ｌ;∧,∨,＊,０,１）中的主理想Ｉ＝（ｄ」成为同余理想的充分必要条件。当Ｌ是局部有限时（即Ａｄ∈Ｓ（Ｌ）,Ｆｄ＝｛ｘ│ｘ＾＊＊＝ｄ｝有限）,对骨架Ｓ（Ｌ）中的每个元素ｄ,我们找到了以Ｉ＝（ｄ」为核心的最小同余关系,利用以上结果我们得到一个Ｓｔｏｎｅ代数是布尔代数的一些等价条件。     

理想簇和根理想

关于环的理想的根有两种定义,一种是所有包含I的极大理想的交,另一种是所有包含I的素理想交,本文主要研究后者定义的一些性质,以及和理想簇V(I)(所有包含I的素理想的集合)的关系.     

Fuzzy格的同余中理想及其W-中理想

本文研究了Fuzzy格的中理想所对应的同余关系问题.利用同余类的方法,得到了中理想与其同态像所对应的同余关系的联系,两个中理想的交与其对应的同余关系交的联系,并证明了Fuzzy格的中理想为W-中理想的一个充分必要条件.     

关于循环环的理想、素理想和极大理想

研究了循环环R=的理想、素理想和极大理想的个数和结构,得到了如下结论:1)理想:(1)若|R|=∞,则R共有无穷多个理想:;(2)若|R|=n,设n的正因数个数为T(n),则R共有T(n)个理想:.2)素理想:(1)若|R|=∞,设a^2=ka(k≥0),①当k=0时,R的素理想只有R;②当k>0时,R的素理想共有无穷多个,它们是:{0}、R及;(2)若|R|=n>1,设a^2=ka,0≤k.3)极大理想:(1)若|R|=∞,则R有无限多个极大理想,它们是;(2)若|R|=n>1,设n的互不相同的素因数个数为ψ(n),则R共有ψ(n)个极大理想:(pa|p是n的素因数).     

幂格的理想与素理想

研究了幂格的理想和素理想,建立了格的理想与格上幂格的理想的一种联系,获得了格的理想(素理想)与它的商格的理想(素理想)之间的关系。     

有界Heyting代数的交换理想与关联理想

运用泛代数和格理论的方法和原理进一步深入研究有界Heyting代数的理想问题。在有界Heyting代数中引入了交换理想、关联理想和正关联理想概念并讨论了它们的性质和相互关系。获得了各种理想的若干等价刻画。证明了在有界Heyting代数中,关联理想和正关联理想等价;在Ockham型有界Heyting代数中,理想和交换理想等价。同时,给出了有界Heyting代数的交换理想成为关联理想的一个充分必要条件。     

Quantale中的素理想及弱素理想

本文把Quantale中的序结构与代数运算＆结合在一起给出了Quantale中素理想和弱素理想的概念。讨论了它们之间的关系,得到了Quantale中理想是(弱)素理想的充要条件。证明了与序半群中的一些经典结论相一致的命题。     

软代数的中理想与素中理想

本文利用软代数的素理想和素滤子刻划了软代数的素中理想，证明了软代数的每一个真中理想都是包含它的素中理想之交。     

所有双理想都是素双理想的半群

设S为一个半群,B是S的一个双理想(即B是S的一个满足条件BSBB的子半群)．如果对S的任意双理想C,D都有CDB蕴涵CB或DB,我们就称B为S的一个素双理想．如果K是一个N-覆盖的纯LR-带,我们就称K为一条拟链．本文证明了半群S的所有双理想都是素双理想的充分必要条件是S是一个幂等元形成拟链的纯整群并半群．     

Subdirectly irreducible sectionally pseudocomplemented semilattices

Sectionally pseudocomplemented semilattices are an extension of relatively pseudocomplemented semilattices—they are meet-semilattices with a greatest element such that every section, i.e., every principal filter, is a pseudocomplemented semilattice. In the paper, we give a simple equational characterization of sectionally pseudocomplemented semilattices and then investigate mainly their congruence kernels which leads to a characterization of subdirectly irreducible sectionally pseudocomplemented semilattices. Supported by the Council of the Czech Government, MSM 6198959214.     

伪补MS-代数的同余关系

本文研究了伪补MS-代数的同余关系.利用正则滤子和伪补代数的对偶窄间理论,得到了正则滤子所生成的同余关系的性质以及同余可换的伪补MS-代数类,从而推广了文献[9]的结果.     

Pseudocomplemented semilattices are finite-to-finite relatively universal

It is shown that the category of directed graphs is isomorphic to a subcategory of the variety S of all pseudocomplemented semilattices which contains all homomorphisms whose images do not lie in the subvariety B of all Boolean pseudocomplemented semilattices. Moreover, the functor exhibiting the isomorphism may be chosen such that each finite directed graph is assigned a finite pseudocomplemented semilattice. That is to say, it is shown that the variety S of all pseudocomplemented semilattices is finite-to-finite B-relatively universal. This illustrates the complexity of the endomorphism monoids of pseudocomplemented semilattices since it follows immediately that, for any monoid M, there exists a proper class of non-isomorphic pseudocomplemented semilattices such that, for each member S, the endomorphisms of S which do not have an image contained in the skeleton of S form a submonoid of the endomorphism monoid of S which is isomorphic to M. Received June 17, 2006; accepted in final form May 8, 2007.     

Congruence properties of pseudocomplemented De Morgan algebras

In this paper we first describe the Priestley duality for pseudocomplemented De Morgan algebras by combining the known dualities of distributive p‐algebras due to Priestley and for De Morgan algebras due to Cornish and Fowler. We then use it to characterize congruence‐permutability, principal join property, and the property of having only principal congruences for pseudocomplemented De Morgan algebras. The congruence‐uniform pseudocomplemented De Morgan algebras are also described.     

On Pseudocomplemented and Stone Ordered Sets

The aim of this paper is to characterize both the pseudocomplemented and Stone ordered sets in a manner similar to that used previously for Boolean and distributive ordered sets. The sublattice G(A) of the Dedekind–Mac Neille completion DM(A) of an ordered set A generated by A is said to be the characteristic lattice of A. We will show that there are distributive pseudocomplemented ordered sets whose characteristic lattices are not pseudocomplemented. We can define a stronger notion of pseudocomplementedness by demanding that both A and G(A) be pseudocomplemented. It turns out that the two concepts are the same for finite and Stone ordered sets.     

双重伪补代数的假值理想的一点注记

介绍了双重伪补代数的假值理想和假值同余的概念,并刻画了它们的某些性质.特别地,给出了双重伪补代数的假值理想和假值同余的特征表示.     

Finite pseudocomplemented lattices: The spectra and the Glivenko congruence

Recently, Gr?tzer, Gunderson and Quackenbush have characterized the spectra of finite pseudocomplemented lattices, solving a problem raised by G. Gr?tzer in his first monograph on lattice theory from 1971. In this note we discuss the tight connection between the spectra and the Glivenko congruence of finite pseudocomplemented lattices.     

Lee classes for pseudocomplemented semilattices, revisited

We give syntactic and semantic characterisations of the Lee classes of the varieties of pseudocomplemented semilattices and pseudocomplemented distributive lattices. The main result clarifies earlier work of K. B. Lee and of the second author.     

伪补MS-代数的滤子同余关系

在伪补MS-代数上引入余核滤子和完全滤子的概念,研究伪补MS-代数的余核滤子和完全滤子的性质,获得了余核滤子和完全滤子生成的同余关系的表达式,证明了具有余核滤子的最小同余关系有同余一致性.     

The model companion of the class of pseudocomplemented semilattices is finitely axiomatizable

It is shown that the class \({\mathcal{PCSL}^{ec}}\) of existentially closed pseudocomplemented semilattices is finitely axiomatizable by appropriately extending a finite axiomatization of the class \({\mathcal{PCSL}^{ac}}\) of algebraically closed pseudocomplemented semilattices. Because \({\mathcal{PCSL}^{ec}}\) coincides with the model companion of the class \({\mathcal{PCSL}}\) of pseudocomplemented semilattices, this answers the question asked by Albert and Burris in a paper in 1986: “Does the class of pseudocomplemented semilattices have a finitely axiomatizable model companion?"