动态优化调度走向实用的策略与段落全局优化

本文在总结动态优化调度在实际系统中应用经验的基础上,提出了动态优化调度走向实用的策略及以段落一局优化算动态化调度的方法,该策略可以较地贯彻电力系统运行“安全,优质,经济”的原则,段落全局优化方法则可以一次性处理各种负荷紧段落,包括单调升降段落及以往方法只有通过反向导引才能够处理的陡升连续等类的段落,具有计算时间短,节省内存等特点,为动态优化调度在电力系统中的进一步实用化打下了坚实的基础。     

Charge-transfer in YBa2Cu3Ox

The charge-transfer hypothesis is shown to be inconsistent with data for YBa₂Cu₃O_x: (i) The two-step behavior ofT _c(x) (with jumps from zero to 60 K and then to 90 K) is not reflected as a similar, statistically significant two-step behavior in the bond-valence-sum charge of cuprate-plane Cu ions (as once believed), (ii) as a consequence of the law of conservation of charge, the derivatives of the layer charges with respect to oxygen contentx for both the Ba-O layers and the charge-reservoir Cu-O chains have the opposite signs to those predicted, and (iii) the charge-transfer observed for superconducting YBa₂Cu₃O_x is not sufficient to produce superconductivity, as demonstrated by insulating PrBa₂Cu₃O_x, which has virtually the same layer charges.     

On a class of optimal abstractions of finite-state machines

Anabstraction A of an fsmM consists in partitioning its states, inputs, and outputs into groups, thus turning it into a non-deterministic fsmM _A. For fixed sets of states, inputs, and outputs, and abstraction generally maps a number of machinesM defined on these sets into the sameM _A. We would like to find anoptimal abstractionA ^* which minimizes this number, while lumping the states, inputs, and outputs into a specified number of classes. We extend these ideas to an fsmM operating in a random environment, and show that the abstraction results in a probabilistic fsm . Thinking of changes inM's output map as resulting in machinesM≠MM, we want to find anA ^* that minimizes the number ofMM which are such that the transition probabilities of their abstracted version are identical to those of the specification machine . SuchMM arise from statistically-undetectable output faults inM. Abstractions are directly applicable to the monitoring of a complex system by an observer for deviations from correct behavior (faults). Complex systems are usually accessible through restricted interfaces, which do not allow the observer to distinguish among all states, inputs, and outputs, thus rendering some faulty transitions undetectable. An optimal interface design will minimize the number of such undetectable faults. Assuming that only single-transition output faults occur inM, we show that each of the classes into which the abstraction lumps the outputs contributes a number of undetectable output faults. We then show that the problem of partitioning the outputs into a given number of classes that minimizes the maximum of these numbers is NP-complete. However, we give (a) an approximate minimization algorithm, running in time linear in the number of classes and quadratic in the number ofM's outputs, and (b) a lower bound on the minimum, computable in the same amount of time. The concept of optimal abstractions is illustrated by numerical results on combinational logic circuits that perform arithmetical operations. The results shed light on the trade-off between model simplification and the ability to detect erroneous behaviors in complex systems.     

ARPO-2: An expert system for legal advice on the breach of building contracts

Although Berman and Hafner [Berman 1989, pp. 928–938] presented the possibility to adapt the model of reasoning of development of an expert system for medical diagnosis to the reasoning of a judge when he/she sentences criminals does not resemble the reasoning found in the decisions of physicians, mathematicians or statisticians.When a lawyer reasons, he/she not only looks for the solution of a case; he/she simultaneously looks for the bases on which his/her reasoning can rest [Galindo 1992, pp. 363–367]. That is to say, he/she not only needs to find the solution but moreover he/she has to find the references (laws, jurisprudence and bibliography) that allow him/her to argue the solution.In many cases, computer solutions to these reasoning processes have been made in a separated way: the solution to the cases using expert systems, and the search of documentation using information retrieval systems.This paper presents the ARPO-2 prototype, a solution integrating the two aspects of legal reasoning: an expert system which is able to simultaneously find the solution to a problem and to give the necessary references so that the lawyer argues the solution. The subject on which the prototype solves problems is the breach of building contracts.In this paper, we describe the process of development of an expert system for solving, justification and documentation of breach of contracts, giving details on the way how the objects that intervene in the case were defined as well as on the reasoning followed.This paper was funded in part by DGICYT, Spanish Civil Law Computerization Project: PB870-632.     

网上拍卖的隐私保护技术研究

文章利用门的安全计算和代理OT协议构造出基于第三方的门的安全计算,构造了可用于密封式拍卖方法的函数,并设计了一个可保护隐私信息的网上拍卖方案。     

基于主题图的公安案件信息资源知识体系研究

文章探讨了将主题图技术应用于公安案件的信息资源组织。通过对主题图技术的概念和理论的介绍,建立了公安案件主题图概念体系。结合实际的公安案件,分析了公安案件中主题及主题间的关联。运用OKS知识开发组件工具进行了具体的构建,最终达到了用Omnigator实现基于语义的主题图浏览,Vizigator实现主题图可视化。     

数据库技术的研究现状及发展趋势

介绍了数据库系统设计过程的六个阶段,即需求分析阶段、概念结构设计阶段、逻辑结构设计阶段、物理结构设计阶段、实施阶段、运行与维护阶段;以分布式数据库系统、知识库系统和主动数据库系统为例,阐述了当前数据库系统研究的现状;结合数据仓库、工程数据库、统计数据库、空间数据库等多种数据库,指出了当前数据库技术的研究热点和发展趋势。     

控制系统动态马尔可夫过程可靠性分析

针对特定试验条件下小子样控制系统可靠性评定的特点,引入故障率分析,介绍了基于马尔可夫过程可维修控制系统的可靠性分析方法,推导了n个部件组成的串联可维修系统可用度的表达式,并针对具体工程用控制系统进行了可用度仿真计算。最后借助可靠性分析软件验证了该方法的合理性。两种方法结论一致,为其他结构可修系统的可靠性分析提供了重要的理论依据。     

面向集团型制造企业的分布式知识管理模型

针对集团型制造企业员工数量大、分布地域广、文化层次差异大等特征,本文提出一种分布式知识管理模型。该模型摒弃传统的由集团公司建设统一知识管理系统的方式,而是采取在集团公司统一规划指导下,从多个维度将各下属子公司知识管理业务分割成多个知识属地,在实施属地局部知识管理的基础上,按照集团公司统一规范完成跨属地的整合,从而形成面向大规模集团型制造企业的分布式松耦合知识管理模式。该模型已在宝钢集团的知识管理实践中得到了初步应用,并有效解决了一系列集团型制造企业在知识管理实践过程中所面临的问题。     

构建信息对抗专业的知识体系和实践教学体系

针对我校信息对抗技术专业的发展方向和培养定位,结合我校办学特色,提出该专业的知识体系和实践教学体系。通过对当前现状和存在问题的分析,研究探讨符合实际的专业教学和人才培养模式。