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981.
982.
以实现电网调度系统SCADA系统实时信息共享为基础 ,提出调度MIS系统的设计思路 ,分析了应用调度MIS系统所需要的SCADA实时数据种类 ,介绍了在数据共享的基础上开发的以调度MIS系统实现的有关电网实时信息二次应用功能 相似文献
983.
Structured text is a general concept that is implicit in a variety of approaches to handling information. Syntactically, an item of structured text is a number of grammatically simple phrases together with a semantic label for each phrase. Items of structured text may be nested within larger items of structured text. The semantic labels in a structured text are meant to parameterize a stereotypical situation, and so a particular item of structured text is an instance of that stereotypical situation. Much information is potentially available as structured text including tagged text in XML, text in relational and object-oriented databases, and the output from information extraction systems in the form of instantiated templates. In this paper, we formalize the concept of structured text, and then focus on how we can identify inconsistency in the logical representation of items of structured text. We then present a new framework for merging logical theories that can be employed to merge inconsistent items of structured text. To illustrate, we consider the problem of merging reports such as weather reports. 相似文献
984.
OBSERVER: An Approach for Query Processing in Global Information Systems Based on Interoperation Across Pre-Existing Ontologies 总被引:3,自引:0,他引:3
Eduardo Mena Arantza Illarramendi Vipul Kashyap Amit P. Sheth 《Distributed and Parallel Databases》2000,8(2):223-271
There has been an explosion in the types, availability and volume of data accessible in an information system, thanks to the World Wide Web (the Web) and related inter-networking technologies. In this environment, there is a critical need to replace or complement earlier database integration approaches and current browsing and keyword-based techniques with concept-based approaches. Ontologies are increasingly becoming accepted as an important part of any concept or semantics based solution, and there is increasing realization that any viable solution will need to support multiple ontologies that may be independently developed and managed. In particular, we consider the use of concepts from pre-existing real world domain ontologies for describing the content of the underlying data repositories. The most challenging issue in this approach is that of vocabulary sharing, which involves dealing with the use of different terms or concepts to describe similar information. In this paper, we describe the architecture, design and implementation of the OBSERVER system. Brokering across the domain ontologies is enabled by representing and utilizing interontology relationships such as (but not limited to) synonyms, hyponyms and hypernyms across terms in different ontologies. User queries are rewritten by using these relationships to obtain translations across ontologies. Well established metrics like precision and recall based on the extensions underlying the concepts are used to estimate the loss of information, if any. 相似文献
985.
Probability-Based Chinese Text Processing and Retrieval 总被引:1,自引:0,他引:1
Xiangji Huang Stephen Robertson Nick Cercone & Aijun An 《Computational Intelligence》2000,16(4):552-569
We discuss the use of probability-based natural language processing for Chinese text retrieval. We focus on comparing different text extraction methods and probabilistic weighting methods. Several document processing methods and probabilistic weighting functions are presented. A number of experiments have been conducted on large standard text collections. We present the experimental results that compare a word-based text processing method with a character-based method. The experimental results also compare a number of term-weighting functions including both single-unit weighting and compound-unit weighting functions. 相似文献
986.
Len Seligman Paul Lehner Ken Smith Chris Elsaesser David Mattox 《Journal of Intelligent Information Systems》2000,14(1):29-50
We are interested in information management for decision support applications, especially those that monitor distributed, heterogeneous databases to assess time-critical decisions. Users of such applications can easily be overwhelmed with data that may change rapidly, may conflict, and may be redundant. Developers are faced with a dilemma: either filter out most information and risk excluding critical items, or gather possibly irrelevant or redundant information, and overwhelm the decision maker. This paper describes a solution to this dilemma called decision-centric information monitoring (DCIM). First, we observe that decision support systems should monitor only information that can potentially change some decision. We present an architecture for DCIM that meets the requirements implied by this observation. We describe techniques for identifying the highest value information to monitor and techniques for monitoring that information despite autonomy, distribution, and heterogeneity of data sources. Finally, we present lessons learned from building LOOKOUT, which is to our knowledge the first implementation of a top-to-bottom system performing decision-centric information monitoring. 相似文献
987.
988.
文中介绍了一种基于网络的新型信息系统构架-总线型信息系统结构。随着计算机软硬件和网络技术的发展,信息系统网络化和系统构架的研究工作成为领域内研究的热点。总线型信息系统从计算机网络化的角度出发研究系统的构建技术,提出了全新的系统结构和开发模型。这个模型有着较好的层次结构和可扩展,可维护性,并对电子审批等应用技术提供了简洁的解决方案,按照该结构设计的信息系统已在一个大型化工企业实现,取得了经济效益。 相似文献
989.
在VIPU系统中,需要对信息的价值进行用户评估。文中设计了一个在线信息评价器,通过对用户评价的实时监控,不断调整评价器的参数,实现对信息价值的最优评价。当评价器受到较大干扰时,专家模块介入评价过程,以保持系统的稳定,仿真实验表明信息评价器有效地实现了信息评价功能。 相似文献
990.