One Class of the Least Congruences on Completely Regular Semigroups

Congruence is a very important aspect in the study of the semigroup theory.In general,the Kernel-trace characterizations,Green's relations and subvarieties are main tools in the consideration of congruences on completely regular semigroups.In this paper,we give one class of congruences on completely regular semigroups with the representation of wreath product of translational hulls on completely simple semigroups.By this new way,the least Clifford semigroup congruences on completely regular semigroups are generalized.

Globals of Completely Regular Monoids

An element of a semigroup S is called irreducible if it cannot be expressedas a product of two elements in S both distinct from itself. In this paper we showthat the class C of all completely regular monoids with irreducible identity elementssatises the strong isomorphism property and so it is globally determined.

A Class of Regular Simple ω2-semigroups-Ⅱ

In this paper, we study regular simple ω2-semigroups in which D｜Es = Wd by the generalized Bruck-Reilly extension and obtain its structure theorem.

Some Characterizations of Left Weakly Regular Ordered Semigroups

In this paper, the notion of left weakly regular ordered semigroups is introduced. Furthermore, left weakly regular ordered semigroups are characterized by the properties of their left ideals, right ideals and （generalized） bi-ideals, and also by the properties of their fuzzy left ideals, fuzzy right ideals and fuzzy （generalized） bi-ideals.

Regular Elements of the Semigroup <i>B</i>_X(<i>D</i>) Defined by Semilattices of the Class &Sigma;₂(<i>X</i>, 8) and Their Calculation Formulas

The paper gives description of regular elements of the semigroup B X (D) which are defined by semilattices of the class Σ2 (X, 8), for which intersection the minimal elements is not empty. When X is a finite set, the formulas are derived, by means of which the number of regular elements of the semigroup is calculated. In this case the set of all regular elements is a subsemigroup of the semigroup B X (D) which is defined by semilattices of the class Σ2 (X, 8).

K-THEORETICALLY COMPLETE VON NEUMANN REGULAR RINGS

The authors introduce the concept of Ko-complete ring and study the properties of Ko-complete unit-regular rings.

The Isomorphism Theorem of Regular Bisimple ω2-semigroups

In this paper we study the isomorphisms of two regular bisimple ω2- semigroups and obtain a criterion for two such semigroups to be isomorphic.

保持等价关系的变换半群的一些结果

给出了保持等价关系的变换半群上的格林关系L,R,H和格林*-关系L^(*),R^(*),H^(*)相容的充要条件,刻画了这类半群的左(右,完全)正则性,得到了这类半群的全体幂等元(正则元,富足元)构成子半群的等价描述.

琼东南盆地所在区块系列井钻井液侵入损害综合分析及优化

琼东南盆地属于中孔低渗储层,储层易发生水化、水锁等伤害。当前区块系列井所用深水钻井液侵入损害类型、机理不明,且传统的钻井液伤害评价方法误差大,不能直观地量化损害程度。因此设计了以钻井液污染实验、扫描电子显微镜(scanning electron microscope,SEM)分析、计算机断层扫描(computed tomography,CT)结合的方式分析钻井液固相以及液相侵入损害储层的方法。结果表明,深水钻井液与地层水配伍性良好,储层水锁损害率处于19.8%~31.4%,液相侵入损害主要为水锁损害;岩心SEM扫描结果显示其孔隙连通性差,EDS测试结果中Ba^(2+)、Ca^(2+)含量较高,分析固相侵入损害主要由加重剂引起,且蒸馏水返排后岩心CT扫描结果显示孔隙度微幅上升表明固相堵塞很难通过自然返排的方式清除。于是通过研发降滤失剂和优选加重剂粒径配比的手段优化深水钻井液储层保护性能。根据理想充填理论,确定最佳配比为1000目CaCO_(3)、600目CaCO_(3)和200目CaCO_(3)的比例为5∶11∶9。优化后体系滤失量显著降低,固相颗粒中径在90μm左右,滤饼致密程度明显提高;渗透率恢复值提高12.1%~19.68%,对该区块钻井液储层保护性能优化具有指导意义。

有限递减变换半群的商半群的一个注记

令Sing n为X n={1,2,…,n}上的奇异变换半群,令S-n={α∈Sing n|xα≤x,x∈X n},这里1<2<…<n.本文得到富足半群S-n的一类同余ρ,其商半群S-n/ρ非正则且既不左富足也不右富足.

由群和变换生成的正则半群

设T_(n)和S_(n)分别是集合X_(n)={1,2,…,n}上的全变换半群和对称群。设K(n,r)={α∈T_(n)|rank(α)≤r},G≤S_(n)和α∈T_(n)S_(n)。借助群论专业软件GAP在前期的摸索,确定了与一类正则变换半群相对应的传递群之间的等价刻画,主要内容如下:1)对K(n,n-2)中的每一个变换α,都是正则半群时,给出了传递群G及其阶数相对应的等价刻画;2)对K(n,3)中的每一个变换α,都是正则半群时,给出了传递群G及其阶数相对应的等价刻画。

磁流体方程全局吸引子的正则性

本文考虑磁流体方程的长时间行为,研究其全局吸引子的正则性。首先,利用分数次空间的嵌入定理和全局吸引子的存在性定理分别得到该方程在空间H 1和H 2中存在全局吸引子;然后,利用迭代方法、线性算子半群的正则性理论和全局吸引子的存在性定理,证明该方程在任意Sobolev空间H^(k)(其中k≥0)中存在全局吸引子,并以H^(k)-范数吸引空间H^(k)中的任意有界集。

半群PS(n,r)的极大子半群

设S_(n),T_(n),P_(n)和P_(n)\T_(n)分别是X_(n)={1,2,...,n}上的对称群、全变换半群、部分变换半群和严格部分变换半群.对0≤r≤n,令SP(n,r)={α∈P_(n)\T_(n):im(α)≤r},则SP(n,r)是部分变换半群P_(n)的双边理想.对0≤r≤n-1,考虑半群的极大子半群PS(n,r)=P(n,r)∪S_(n).进一步,获得了半群PS(n,r)的极大子半群和极大正则子半群是一致的.

基于无人机摄影测量的潮间带单波束测深空间插值精度评估

针对单波束测深数据插值模型精度验证困难等问题,利用潮间带潮汐规律,提出了一种基于高精度无人机数据验证插值模型精度的方法。在低潮时利用无人机摄影测量构建高精度潮间带数字表面模型,高潮时获取单波束测深数据并结合全球导航卫星系统技术计算得出潮间带地形点的三维坐标,使用克里金插值法、反距离权重法、规则样条函数法以及自然邻域法分别构建潮间带数字高程模型。以无人机数字表面模型数据为基准,分别对4种插值方法构建的潮间带数字高程模型进行精度分析。结果表明:1)后处理差分技术辅助无人机摄影测量可以构建高精度潮间带数字表面模型。2)在潮间带区域可以使用无人机数据作为单波束测深数据精度的评价标准。3)潮间带地形较为平坦时,规则样条函数法相比于其他3种插值方法精度更高,粗差率为12.5%。

完全正则三部图与二部图的笛卡尔积的亏格

设Km,m,m(m≥1)是一个完全正则三部图,G是一个围长大于4的二部图.当G的最大度不大于2m时,本文得到完全正则三部图Km,m,m与G的笛卡尔积的亏格.我们的结果推广了Bonnington和Pisanski关于Km,m,m与偶圈的笛卡尔积的亏格.此外,我们还得到了Km,m,m与一些非二部图的笛卡尔积的不可定向亏格.

EXISTENCE AND REGULARITY OF SOLUTIONS TO MODEL FOR LIQUID MIXTURE OF ^3HE-^4HE

Existence and regularity of solutions to model for liquid mixture of 3He-4He is considered in this paper. First, it is proved that this system possesses a unique global weak solution in H^1 （Ω, C ×R） by using Galerkin method. Secondly, by using an iteration procedure, regularity estimates for the linear semigroups, it is proved that the model for liquid mixture of 3He-4He has a unique solution in H^k（Ω, C × R） for all k ≥ 1.

An Iterative Algorithm for Generalized Mixed Equilibrium Problems and Fixed Points of Nonexpansive Semigroups

In this works, by using the modified viscosity approximation method associated with Meir-Keeler contractions, we proved the convergence theorem for solving the fixed point problem of a nonexpansive semigroup and generalized mixed equilibrium problems in Hilbert spaces.

WEAK REGULARIZATION FOR A CLASS OF ILL-POSED CAUCHY PROBLEMS

This article is concerned with the ill-posed Cauchy problem associated with a densely defined linear operator A in a Banach space. A family of weak regularizing operators is introduced. If the spectrum of A is contained in a sector of right-half complex plane and its resolvent is polynomially bounded, the weak regularization for such ill-posed Cauchy problem can be shown by using the quasi-reversibilky method and regularized semigroups. Finally, an example is given.

Zappa-Szép Products of Semigroups

The internal Zappa-Szép products emerge when a semigroup has the property that every element has a unique decomposition as a product of elements from two given subsemigroups. The external version constructed from actions of two semigroups on one another satisfying axiom derived by G. Zappa. We illustrate the correspondence between the two versions internal and the external of Zappa-Szép products of semigroups. We consider the structure of the internal Zappa-Szép product as an enlargement. We show how rectangular band can be described as the Zappa-Szép product of a left-zero semigroup and a right-zero semigroup. We find necessary and sufficient conditions for the Zappa-Szép product of regular semigroups to again be regular, and necessary conditions for the Zappa-Szép product of inverse semigroups to again be inverse. We generalize the Billhardt λ-semidirect product to the Zappa-Szép product of a semilattice E and a group G by constructing an inductive groupoid.

Notes on Preregular Operators in Banach Lattices

Some characterizations of preregular operators between two Banach lattices are presented. Then several sufficient conditions for preregular operators being regular are given, and some related results are also obtained.