A lattice-theoretical perspective on adhesive categories

It is a known fact that the subobjects of an object in an adhesive category form a distributive lattice. Building on this observation, in the paper we show how the representation theorem for finite distributive lattices applies to subobject lattices. In particular, we introduce a notion of irreducible object in an adhesive category, and we prove that any finite object of an adhesive category can be obtained as the colimit of its irreducible subobjects. Furthermore we show that every arrow between finite objects in an adhesive category can be interpreted as a lattice homomorphism between subobject lattices and, conversely, we characterize those homomorphisms between subobject lattices which can be seen as arrows.     

On (finite) distributive lattices with antitone involutions

Distributive lattices with antitone involutions (or equivalently, distributive basic algebras) are studied. It is proved that in the finite case their underlying lattices are isomorphic to direct products of finite chains, and hence finite distributive basic algebras can be constructed by “perturbing” finite MV-algebras, and moreover, under certain natural conditions, they even coincide with finite MV-algebras. Sharp elements in basic algebras satisfying these natural conditions are studied, too.     

基于半连接的分布式数据库查询优化算法探讨

采用连接操作实现分布式数据查询时,不仅代价较高而且费时。若利用半连接查询操作取代连接操作,可以通过缩减操作数获得查询优化。而两次半连接对接算法可以更大限度地缩减操作数,实现起来更为简单、高效。针对多节点的数据查询,提出了通过最小生成树算法生成并行的连接序对,并由两次半连接对接算法进行查询优化处理的算法。应用该算法可以有效利用多节点的并行性缩短系统的查询响应时间,降低系统的总开销。算法在海量信息查询中具有实用价值。     

Prime algebraicity

A prime algebraic lattice can be characterised as isomorphic to the downwards-closed subsets, ordered by inclusion, of its complete primes. It is easily seen that the downwards-closed subsets of a partial order form a completely distributive algebraic lattice when ordered by inclusion. The converse also holds; any completely distributive algebraic lattice is isomorphic to such a set of downwards-closed subsets of a partial order. The partial order can be recovered from the lattice as the order of the lattice restricted to its complete primes. Consequently prime algebraic lattices are precisely the completely distributive algebraic lattices. The result extends to Scott domains. Several consequences are explored briefly: the representation of Berry’s dI-domains by event structures; a simplified form of information systems for completely distributive Scott domains; and a simple domain theory for concurrency.     

On derivations of lattices

In this paper, we introduce the notion of derivation for a lattice and discuss some related properties. We give some equivalent conditions under which a derivation is isotone for lattices with a greatest element, modular lattices, and distributive lattices. We characterize modular lattices and distributive lattices by isotone derivation. Moreover, we prove that if d is an isotone derivation of a lattice L, the fixed set Fix_d(L) is an ideal of L. Finally, we prove that D(L) is isomorphic to L in a distributive lattice L.     

基于RTI的分布式电子商务系统的设计

分布式体系是电子商务系统的一般结构,RTI作为一种分布式仿真软件体系,在构建电子商务系统中具有其独特的优势。该文主要介绍基于RTI协议来建立电子商务系统,主要分析了电子商务系统中对象类的划分与分布式网络模型的构建,特别针对RTI系统中为减少网络冗余量的问题,而分析了区域分割的算法。     

合作对策的一种新的分配方式

提出了合作对策的一种新的分配方式，给出了这种新分配方式的确定性条件和它满足的理性行为和合理性原则。最后，比较了这种分配方式与其它分配方式的异同性。     

基于扩张的模糊软集运算

利用映射扩张给出了模糊软集的新的定义,并且验证了在新运算下所有模糊软集构成有界分配格。     

Web页面标注模型及其实现

为改善基于Web的远程教育的交互性,提出了一种Web页面嵌入标注模型,讨论了该模型的实现.该模型不但实现了在线对任意服务器上的Web页面进行直接标注,而且实现了标注的精确定位以及标注信息的共享和重组.     

链路容量分配的最小最大原则并分组优化算法

本文人出了一种链路容量分配的新算法,应用此算法,不但可以得到与已工法的链路容量分配相同的结果,而且还可以被用户所接受,在尽量减少链路时延差异情况下,具有了小网络时延的链上发配结果,对于通信软件和优化计算机网络,具有一定的指导意义。     

SharedWeb—a shared virtual environment over the World Wide Web

The design, implementation and experimental results of a multiple-user 3D web-browsing system, called the SharedWeb system, are described in this paper. The system is based on the request–response method of the WWW server. The key features of this system include the ability of the WWW server to remember all the browsers connected to it in order to transmit the messages required to maintain consistent states among browsers. The dead-reckoning technique of distributive interactive simulation (DIS) is used by browsers in order to reduce the number of messages sent onto the network and to satisfy the timing requirement demanded by the virtual environment. The protocol data unit (PDU) defined in DIS is also adapted by the SharedWeb system not only to communicate information among browsers but also to integrate with the DIS environment in the near future. © 1998 John Wiley & Sons, Ltd.     

基于三层结构的分布式人才信息管理系统

讨论了基于三层结构的分布式数据处理技术和多媒体技术,以及在信息管理系统中的实现。     

Resolution-based decision procedures for the universal theory of some classes of distributive lattices with operators

We establish a link between the satisfiability of universal sentences with respect to classes of distributive lattices with operators and their satisfiability with respect to certain classes of relational structures. This justifies a method for structure-preserving translation to clause form of universal sentences in such classes of algebras. We show that refinements of resolution yield decision procedures for the universal theory of some such classes. In particular, we obtain exponential space and time decision procedures for the universal clause theory of (i) the class of all bounded distributive lattices with operators satisfying a set of (generalized) residuation conditions, and (ii) the class of all bounded distributive lattices with operators, and a doubly-exponential time decision procedure for the universal clause theory of the class of all Heyting algebras.     

大型分布式企业网络安全防护

大型分布式企业，其主要特征一是“大”，二是“分布式”。由于这样的特点存在，在它们的网络安全防护上势必反映出与小型组织机构型的企业不同，导致其安全解决方案的不同。分析了大型分布式企业网络的安全需求，重点论述了如何解决其网络安全防护的问题。     

利用分布式对象技术建立的一种网络管理模型

随着计算机网络的复杂化和异构化，传统的集中式网络管理模式已不适应目前网络管理的需求，而分而式网络管理正好符合网络技术迅速发展趋势，本文在分析传统的集中式网络管理模型的基础上，讨论基于Web的网络管理的三种实现方式，利用分布式对象技术建立了一种网络管理模型，并简要介绍了利用CORBA规范的Java技术来实现Web网络管理的方法。     

Automata theory based on quantum logic: some characterizations

Automata theory based on quantum logic (abbr. l-valued automata theory) may be viewed as a logical approach of quantum computation. In this paper, we characterize some fundamental properties of l-valued automata theory, and discover that some properties of the truth-value lattices of the underlying logic are equivalent to certain properties of automata. More specifically (i) the transition relations of l-valued automata are extended to describe the transitions enabled by strings of input symbols, and particularly, these extensions depend on the distributivity of the truth-value lattices (Proposition 3.1); (ii) some properties of the l-valued successor and source operators and l-valued subautomata are demonstrated to be equivalent to a property of the truth-value lattices which is exactly equivalent to the distributive law (Proposition 4.3 and Corollary 4.4). This is a new characterization of Boolean algebras in the framework of l-valued automata theory; (iii) we verify that the intersection of two l-valued subautomata is still an l-valued subautomaton if and only if the multiplication (&) is distributive over the union in the truth-value lattices (Proposition 4.5), which is strictly weaker than the usual distributivity; (iv) we show that some topological characterizations in terms of the l-valued successor and source operators also rely on the distributivity of truth-value lattices (Theorem 5.6). Finally, we address some related topics for further study.     

分配序列效应代数的理想和同余

分配的序列效应代数（简记为DSEA）,是指在一个效应代数上带有一种乘积运算并满足一定的条件。介绍了分配的序列效应代数中的左理想、右理想、理想、素理想和同余等概念,并且证明了满足（RDP）性质并且以1为乘积单位的分配序列效应代数是具有（RDP）性质的反格分配序列效应代数的子直积。     

基于分配格理论的大规模线速组播交换系统

采用Altera公司的StratixIV系列FPGA芯片为平台,根据代数分配格理论,构造适合组播的排序结构;结合已建立的多路径自路由结构;最终构造出基于代数分配格的线速组播交换结构。同时,研究此结构应用于大规模组播交换的方法,并设计支持该结构的自路由组播线速扇出复制过程的带内信令机制和控制机制。     

Remarks on minimal solutions of a system of fuzzy relation equations over complete infinitely distributive lattices

In Section 3.6 of Fuzzy relation equations and their applications to knowledge engineering. Kluwer Academic Publishers, Boston (1989), Di Nola et al. presented a procedure to find a minimal solution from a fixed solution of a system of fuzzy relation equations over complete infinitely distributive lattices, and put the question: is the minimal solution found by the procedure unique or not? In this paper, we give a negative answer to the question and make some further remarks. We not only give a necessary and sufficient condition for the uniqueness of such minimal solutions, but also characterize the existence of the least solution and a unique solution of a system of fuzzy relation equations over complete infinitely distributive lattices.