Sublattices Generated by Polars

In an algebraic frame L, the complete sublattice CP(L) generated by the polars of L is studied, in comparison with FP(L), the subframe generated by the polars. It is shown, by an example from the theory of ?-groups, that these are distinct, in general. The relationship between FP(L), CP(L), and other established constructs, closely related to the boolean algebra of polars, is also studied.     

Rings characterized by injectivity classes

Recently, there are a number of well known theorems which char­acterize rings in terms of injective modules (cf. [2], [3], [5] and [8]). The purpose of this paper is to give general theorems which show that some similar results remain true when many other classes of general injective modules are considered in place of injective modules. Our results encompass several well known results by Huynh and Smith, Liu, and Xue. In particular we answer negatively the question of Yue Chi Ming [11] and an example is given to show that E—injective modules form an intermediate class between continuous and quasi-continuous modules(cf. Example 3).     

The reconstruction of a special kind of periodic Jacobi matrices

In this paper, we investigate the properties of a special kind of periodic Jacobi matrices. We show that the solution of the inverse problem for periodic Jacobi matrices is unique if and only if the matrix is of that special kind. Moreover, we present an algorithm to construct the solution of that inverse problem and give some illustrative examples. Finally, we perform a stability analysis of the algorithm.     

一类特殊的对称的块循环矩阵的特征值

In this paper, the spectrum and characteristic polynomial for a special kind of symmetric block circulant matrices are given.     

一类特殊二次分配问题的线性化求解新方法

许多抽象于实际的二次分配问题,其流矩阵与距离矩阵中有很多零元素,求解该类二次分配问题时,可通过先行利用零元素的信息减小问题规模,缩短计算时间．以二次分配问题的线性化模型为基础,提出了一种求解流矩阵与距离矩阵中同时存在大量零元素的二次分配问题新方法,不仅从理论上证明了方法的可行性,而且从实验的角度说明了该方法比以往方法更加优越．     

一类特殊优化问题的光滑梯度法

对一类在压缩感知、图像处理等相关领域有广泛应用的特殊非光滑优化问题进行了研究,给出了求解此类问题的光滑梯度法及算法的全局收敛性证明,相关的数值实验表明算法的有效性.     

The infima of functionals of a special kind on a compact convex set

It is proved that the infimum of the ratio of a concave functional and a convex functional is attained at the extreme points of a compact convex set in a normed linear space. A criterion for the membership of a given element in the set of extreme points is proposed and the existence of a strongly convex functional on a compact set is shown.     

Sublattices of regular elements

Let L be an r-lattice, i.e., a modular multiplicative lattice that is compactly generated, principally generated, and has greatest element 1 compact. We consider certain subsets of L consisting of regular elements: there is a compact element with there is a principal element is a principal element with (0:X_{\alpha })=0\} . The first three subsets L_{f}, L_{sr}, and L_{r} are augmented filters on L, i.e., is a multiplicatively closed subset of $L$ with $A\in and $B\geq A$ with $B\in L$ implies $B\in and hence are sublattices of $L$ closed under multiplication. We first consider the more general situation of augmented filters on $L.$ These results are then applied to study the four previously defined subsets for $L$ an $r$-lattice or Noether lattice (i.e., an $r$-lattice with ACC). Finally, we give a brief discussion of how the results for augmented lattices can be applied to subsets of $L$ which are regular with respect to an $L$-module.     

Characterizations of Complete Sublattices of a Given Complete Lattice

To characterize all complete sublattices of a given complete lattice is an important problem. In this paper we will give three different characterizations of complete sublattices of a complete lattice by using closure operators, kernel operators, and by using Galoisclosed subrelations.The research was supported by a grant of the faculty of Science ChiangMai University Thailand.     

Averaging method for pulse systems with Markov switchings of a special kind

We study pulse systems with Markov switchings, consider the averaging principle, and analyze the stability of the averaged equation.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 47, No. 10, pp. 1376–1386, October, 1995.     

Sublattices of associahedra and permutohedra

Grätzer asked in 1971 for a characterization of sublattices of Tamari lattices. A natural candidate was coined by McKenzie in 1972 with the notion of a bounded homomorphic image of a free lattice—in short, bounded lattice. Urquhart proved in 1978 that every Tamari lattice is bounded (thus so are its sublattices). Geyer conjectured in 1994 that every finite bounded lattice embeds into some Tamari lattice.     

SF-环的内射性

研究了SF-环与P-内射环的关系,构造了SF-环成为P-内射环的一系列条件.证明了SF-环R只要满足其中之一:R的每个极大左理想是有限生成的;特殊右零化子的降链条件;对R的每个极大左理想M,l(M)在R中是本质的,那么R就是P-内射环.在此基础上,利用一定条件下SF-环的P-内射性,发展了SF-环的若干新结果,这些结果部分地拓展了有关文献中的结果.