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101.
关系数据库在专家系统中的应用 总被引:6,自引:0,他引:6
在传统的专家系统中,对推理机工作过程的控制是程序实现的。本文介绍了一个用数据库技术引导推理过程的专家系统-精神分裂症诊断专家系统(ESSD)的推理控制策略。在这个专家系统中,作者将有关推理过程的控制信息用关系数据库技术进行存储和管理,达到了将控制策略数据化的目的。将数据库技术引入到专家系统的推进控制机制中可以使控制策略比较容易调整,且而可以大大压缩程序篇幅,显著提高系统运行效率,为专家系统的结构设 相似文献
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Martin Sulzmann Kenny Zhuo Ming Lu 《Electronic Notes in Theoretical Computer Science》2006,148(2):239
We consider the problem of integrating XDuce into ML. This is difficult because of incompatible type and value representations. Our solution is a type-driven translation scheme from XDuce to ML based on a structured representation of XDuce values. XDuce type inference guides the insertion of appropriate coercion functions to translate regular expression pattern matching and uses of semantic subtyping. We can extend our translation scheme to include ML function calls and patterns into XDuce. Thus, we can embed XDuce into ML. Our results allow to enrich the ML language with support for dealing with semi-structured data. 相似文献
105.
In the last decade there was growing interest in strategic management literature about factors that influence a company's ability to use IT. There is general consensus that knowledge and competency are necessary in developing an IT capability, but there is very little understanding of what the necessary competencies are, and how they influence IS usage in different contexts. The small and medium-sized enterprise context is particularly interesting for two reasons: it constitutes a major part of the economy and it has been relatively unsuccessful in exploiting e-business. 相似文献
106.
下部钻具组合力学性能分析中,稳定器与井壁的间隙是影响其性能的重要因素。对于多稳定器组合,事先设定稳定器与井壁接触情况既困难也不准确。本文从有限单元的基本总势能表达式出发,采用最优化理论中的罚函数法,分析了稳定器间隙对下部钻具力学性能的影响,为解决稳定器与井壁的接触问题找到了一个新方向。 相似文献
107.
Ioanna Roussaki Maria Strimpakou Carsten Pils 《Journal of Network and Systems Management》2007,15(1):57-74
The challenge of saturating all phases of pervasive service provision with context-aware functionality lies in coping with
the complexity of maintaining, retrieving and distributing context information. To efficiently represent and query context
information a sophisticated modelling scheme should exist. To distribute and synchronise context knowledge in various context
repositories across a multitude of administrative domains, streamlined mechanisms are needed. This paper elaborates on an
innovative context management framework that has been designed to cope with free-text and location based context retrieval
and efficient context consistency control. The proposed framework has been incorporated in a multi-functional pervasive services
platform, while most of the mechanisms it employs have been empirically evaluated. 相似文献
108.
We developed a noble technique for the fine-particle handling in plasmas. In this method a pair of point electrodes are introduced in the plasma, to which positive pulses are applied alternatively. When the pulse repetition period is shorter than the particle response time, the particles feel only time-averaged force because of their large mass. Spatial profile of the equivalent potential of the time-averaged force varies from a circle to an ellipse with an increase in the local discharge at the electrodes. The particles are eventually transported toward a middle point between two point-electrodes, being almost independent of their initial positions. This method is quite effective for converging fine particles in the plasma. 相似文献
109.
Abstract. Deciding when to adopt or introduce new information technology (IT) is a relatively difficult problem. This paper presents a method that can be used in many circumstances to evaluate new IT. The model is based on modelling the response of customers and rivals to services provided by IT. The methodology recognizes competitor reactions on two levels: within the local market and actions by rivals in the international market. The model examines behaviour, costs, and benefits over time. Several different types of models are examined, ranging from competitive (Nash) equilibriums to joint ventures. This model is illustrated by examining when banks should implement new technology. The results indicate that large banks can effectively utilize technology as a strategic weapon. Smaller, local banks are more limited in their control of technology. The model reveals some strategic uses that are not evident from existing models. 相似文献
110.