Boolean and distributive ordered sets: Characterization and representation by sets

Boolean ordered sets generalize Boolean lattices, and distributive ordered sets generalize distributive lattices. Ideals, prime ideals, and maximal ideals in ordered sets are defined, and some well-known theorems on Boolean lattices, such as the Glivenko-Stone theorem and the Stone representation theorem, are generalized to Boolean ordered sets. A prime ideal theorem for distributive ordered sets is formulated, and the Birkhoff representation theorem is generalized to distributive ordered sets. Fundamental are the embedding theorems for Boolean ordered sets and for distributive ordered sets.Financial support of the Grant Agency of the Czech Republic under the grant No. 201/93/0950 is gratefully acknowledged.     

弱可约序半群的理想扩张

NioviKehayopulu和Michael Tsingelis于2003年给出了关于序半群的理想扩张的一个定理,本文利用该定理进一步给出了弱可约序半群的理想扩张的构造．     

Convergence theorems for HL integrable vector-valued functions with applications

In this paper we prove dominated and monotone convergence theorems for HL integrable Banach-valued functions. These results and a fixed point theorem in ordered spaces are then applied to prove existence and comparison results for integral equations of Fredholm type in ordered Banach spaces involving Kurzweil integrals or improper integrals. Results are used also to solve concrete second-order functional boundary value problems involving discontinuities and singularities.     

上下解方法给出具有时滞随机泛函微分方程解的存在性(英文)

讨论了具有不连续飘逸系数具有时滞的随机泛函微分方程,通过上下解方法和序拓扑空间中不动点原理给出了其解的存在性定理.     

端单调线性泛函的存在性(英文)

讨论了偏序线性空间的代数对偶空间上的端单调线性泛函的延拓性．进一步,还推导出端单调线性泛函的存在性定理．     

Categorical Abstract Algebraic Logic: Ordered Equational Logic and Algebraizable PoVarieties

A syntactic apparatus is introduced for the study of the algebraic properties of classes of partially ordered algebraic systems (a.k.a. partially ordered functors (pofunctors)). A Birkhoff-style order HSP theorem and a Mal’cev-style order SLP theorem are proved for partially ordered varieties and partially ordered quasivarieties, respectively, of partially ordered algebraic systems based on this syntactic apparatus. Finally, the notion of a finitely algebraizable partially-ordered quasi-variety, in the spirit of Pałasińska and Pigozzi, is introduced and some of the properties of these quasi-povarieties are explored in the categorical framework.      

Ordered *-Algebras with an Order Unit

We develop a theory of ordered *-algebras with an order unit. These are complex algebras equipped with a conjugate-linear vector space involution whose hermitian elements form an ordered real algebra with an order unit but not necessarily with a multiplicative identity. Our main result is a representation theorem for ordered *-algebras with an order unit. This can be viewed as the complex and the non-unital version of the representation theorem of Stone and Kadison for ordered real algebras containing an order unit which is a multiplicative identity. A key role in our approach is played by certain weighted function algebras.     

On properties of interpolation groups

Partially ordered groups satisfying the interpolation condition (and not necessarily directed) are considered. It is proved that an isomorphism theorem holds for these groups (this theorem fails to hold for partially ordered groups in the general case). A criterion for almost orthogonality of positive elements of interpolation groups is found. The location of a subgroup associated with a pair of almost orthogonal elements in the lattice of subgroups of an interpolation group is described.     

On a theorem of Bourbaki

A simple proof of the theorem of Bourbaki [2] on ordered sets is deduced from a necessary and sufficient condition in order that a well ordered subsetA be a segment of another subsetB.     

A non-commutative version of the first alexandroff decomposition theorem in ordered topological groups

In this paper we establish a decomposition theorem for a positive regular measure on an orthoalgebra with values in an ordered topological group not necessarily commutative. We deduce from it the A. D. Alexandroff’s classical first decomposition theorem and we discuss its uniqueness in the setting of metric spaces.     

A generalized section theorem and a minimax inequality for a vector-valued mapping 1

A generalized Fan's section theorem has proposed by replacing convexity assumptions with merely topological properties. A generalized reformulation of Browder's fixed point theorem has derived. The Minimax Inequalities for vector-valued mapping in an ordered Banach space have established without the convexity and with convexity, respectively.     

Path-dependent estimation of a distribution under generalized censoring

This paper focuses on the problem of estimating a bivariate distribution when the data points are subject to censoring by a general class of randomsets. A path-dependent estimator for the distribution is proposed. The estimator is sequential in the sense that at any fixed point, it depends only on the data preceding the point. If the censoring mechanism is totally ordered, the paths may be chosen in such a way that the estimate of the distribution is an increasing function. In this case, a functional central limit theorem is proven for the estimator. Applications are discussed, and the validity of bootstrap methods is established.     

Unimodular modules

The present publication is mainly a survey paper on the author's contributions on the relations between graph theory and linear algebra. A system of axioms introduced by Ghouila-Houri allows one to generalize to an arbitrary Abelian group the notion of interval in a linearly ordered group and to state a theorem that generalizes two due to A.J. Hoffman. The first is on the feasibility of a system of inequalities and the other is Hoffman's circulation theorem reported in the first Berge's book on graph theory. Our point of view permitted us to prove classical results of linear programming in the more general setting of linearly ordered groups and rings. It also shed a new light on convex programming.     

Some conditions for hypervaluability of a ring by a totally ordered semigroup

The purpose of this paper is to give some conditions for a ring to be hyperbaluable by a totally ordered semigroup. In § 1 we give some preliminary definitions and results, and a bibliographical note. The theorem in § 2 provides a sufficient condition for hypervaluability. The theorem in § 3 provides a necessary and sufficient condition for hypervaluability. In § 4 we provide an example of a ring satisfying the conditions of theorem 2 and is therefore hypervaluable by a totally ordered semigroup.     

拓扑序空间中的广义向量值均衡问题

利用一个KKM型定理,在拓扑序空间中,建立了关于广义向量值均衡问题解的某些新的存在性定理.     

REGULAR RELATIONS AND MONOTONE NORMAL ORDERED SPACES

In this paper the classical theorem of Zareckii about regular relations is generalized and an intrinsic characterization of regularity is obtained. Based on the generalized Zareckii theorem and the intrinsic characterization of regularity, the authors give a characterization of monotone normality of ordered spaces. A new proof of the Urysohn-Nachbin lemma is presented which is quite different from the classical one.     

Ideals in ordered sets, a unifying approach

A common generalization of different notions of ideals met in literature together with the associated notions of distributivity in ordered sets are studied. A restricted prime ideal theorem is proved. Moreover, a new characterization of algebraic topped intersection structures is presented.     

Suzuki?s type characterizations of completeness for partial metric spaces and fixed points for partially ordered metric spaces

Recently, Suzuki [T. Suzuki, A generalized Banach contraction principle that characterizes metric completeness, Proc. Amer. Math. Soc. 136 (2008) 1861-1869] proved a fixed point theorem that is a generalization of the Banach contraction principle and characterizes the metric completeness. In this paper we prove an analogous fixed point result for a self-mapping on a partial metric space or on a partially ordered metric space. Our results on partially ordered metric spaces generalize and extend some recent results of Ran and Reurings [A.C.M. Ran, M.C. Reurings, A fixed point theorem in partially ordered sets and some applications to matrix equations, Proc. Amer. Math. Soc. 132 (2004) 1435-1443], Nieto and Rodríguez-López [J.J. Nieto, R. Rodríguez-López, Contractive mapping theorems in partially ordered sets and applications to ordinary differential equations, Order 22 (2005) 223-239]. We deduce, also, common fixed point results for two self-mappings. Moreover, using our results, we obtain a characterization of partial metric 0-completeness in terms of fixed point theory. This result extends Suzuki?s characterization of metric completeness.     

The intertwining lifting theorem for ordered groups

Sz.-Nagy's dilation theorem for a contraction on a Hilbert space has been extended by Mlak to the case of a contraction semigroup whose indices are the positive elements of a totally ordered discrete group. We generalize to this case the intertwining lifting theorem of Sz.-Nagy and Foias. Some previous interpolation results on ordered groups are obtained as consequences.