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121.
陈敏  蔡筱英 《情报学报》2003,22(5):597-601
随着我国加入WTO ,企业所面临的外部环境正在发生迅速变化 ,这对企业的决策提出了更高的要求。文章通过分析企业现有决策方式和OLTP系统存在的问题 ,介绍了决策支持系统技术的研究现状和发展趋势 ,阐述了基于数据仓库的决策支持系统的关键技术和设计与实现方法 ,提出了企业在DSS建设中需注意的一些问题  相似文献   
122.
This article describes four semesters of introductory statistics courses that incorporate service learning and gardening into the curriculum with applications of the binomial distribution, least squares regression and hypothesis testing. The activities span multiple semesters and are iterative in nature.  相似文献   
123.
Using document analysis, this paper examines the historical emergence of the quantified child, revealing how the collection and use of data has become normalized through legitimizing discourses. First, following in the traditions of Foucault's genealogy and studies examining the sociology of numbers, this paper traces the evolution of data collection in a range of significant education policy documents. Second, a word count analysis was used to further substantiate the claim that data collection and use has been increasingly normalized through legitimizing discourses and routine actions in educational settings. These analyses provide evidence that the need to quantify educational practices has been justified over long periods of time through a variety of documents and that the extent to which data governs educators’ thoughts, discourses, and actions has dramatically increased during the past century.  相似文献   
124.
数字图书馆中IDSS的研究   总被引:2,自引:0,他引:2  
胡蓉  张渝  章雷 《情报科学》2004,22(1):92-95
本文在分析数字图书馆决策特点的基础上,提出了一个多专家系统集成式的基于数据挖掘和智能代理技术的智能决策支持系统框架。  相似文献   
125.
以键宽和键高查询为例子,以小见大阐述数据查询的实现。键宽键高查询以Delphi中的ADO组件连接加密的MS—ACCESS数据库实现。我希望通过本文企业和工厂中的机械设计人员由此掌握一种应用程序开发工具,从耗力耗时易错的手工查询摆脱出来,这对以后的工作和学习大有裨益。  相似文献   
126.
简述了图像数据库的发展,对图像数据库的结构、分类及其特性进行了研究。并讨论了图像数据库的数据模型。最后给出了图像数据库的检索方法。  相似文献   
127.
This paper examines some of the combinatorial issues associated with the batch data association problem arising in tracking and correlation applications. A procedure is developed that addresses a large class of data association problems involving the calculation of permanents of submatrices of the original association matrix. This procedure yields what is termed the Joint Assignment Matrix (JAM), which can be used to optimally rank associations for hypothesis selection. Because the computational cost of the permanent scales exponentially with the size of the matrix, improved algorithms are developed both for calculating the exact JAM and for generating approximations to it. Empirical results suggest that at least one of the approximations is suitable for real-time hypothesis generation in large scale tracking and correlation applications. Novel theoretical results include an improved upper bound on the calculation of the JAM and new upper bound inequalities for the permanent of general nonnegative matrices. One of these inequalities is an improvement over the best previously known inequality.  相似文献   
128.
A fault diagnosis method for analog circuit is proposed in this paper. An all-purpose amplifier is taken as the typical circuit under test (CUT). The chaotic signal, which is generated by an improved Chua's circuit, is employed as the excitation signal of CUT. The algorithm for phase-space reconstruction of chaotic time series is a combination algorithm of multiple autocorrelation and Γ-test. The circuit state is estimated based on detecting the geometric change of Chua's attractor with a data-mining approach. For the purpose of information fusion, another eight features are extracted from the testing data to comprehensively determine the CUT states. A discussion is made for comparing the effectiveness of each feature according to the testing results.  相似文献   
129.
Current citation-based document retrieval systems generally offer only limited search facilities, such as author search. In order to facilitate more advanced search functions, we have developed a significantly improved system that employs two novel techniques: Context-based Cluster Analysis (CCA) and Context-based Ontology Generation frAmework (COGA). CCA aims to extract relevant information from clusters originally obtained from disparate clustering methods by building relationships between them. The built relationships are then represented as formal context using the Formal Concept Analysis (FCA) technique. COGA aims to generate ontology from clusters relationship built by CCA. By combining these two techniques, we are able to perform ontology learning from a citation database using clustering results. We have implemented the improved system and have demonstrated its use for finding research domain expertise. We have also conducted performance evaluation on the system and the results are encouraging.  相似文献   
130.
本文讨论了计算机实验室管理系统中安全方面存在的问题,并从服务器安全、网络安全、数据通信安全和数据库安全等几个方面进行了分析研究,提出了防止计算机实验室管理系统中数据被非法窃取、篡改的几种安全措施,消除了计算机实验室管理系统中潜在的安全隐患问题。  相似文献   
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