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1.
传统关联规则挖掘在面临分类决策问题时,易出现非频繁规则遗漏、预测精度不高的问题。为得到正确合理且更为完整的规则,提出了一种改进方法 DT-AR(decision tree-association rule algorithm),利用决策树剪枝策略对关联规则集进行补充。该方法利用FP-Growth(frequent pattern growth)算法得到关联规则集,利用C4.5算法构建后剪枝决策树并提取分类规则,在进行置信度迭代筛选后与关联规则集取并集修正,利用置信度作为权重系数采取投票法进行分类。实验结果表明,与传统关联规则挖掘和决策树剪枝方法相比,该方法得到的规则在数据集分类结果上更准确。  相似文献   

2.
基于范例推理的税收案例分析系统设计   总被引:2,自引:1,他引:1  
基于范例推理技术是专家系统实用而成熟的技术。对税收案例分析而言,其应用在实用性方面优于基于规则的系统。提出基于范例推理技术和应用XML来表示和搜索范例,应用数据仓库构建税收案例分析系统,详细介绍了系统的基于范例推理流程、相似性度量函数、范例相似匹配方法及范例维护的设计思路和实现步骤。利用基于范例推理技术,大大提高了系统的“智能”性和实际功能,在实际应用中产生了较好的经济效益和社会效益。  相似文献   

3.
一种集成数据挖掘的自动视频分类方法   总被引:1,自引:0,他引:1  
针对自动视频分类工作中分类预测精度低的问题,提出了一种集成数据挖掘技术的自动视频分类方法。首先进行视频分割,形成了一个视频属性数据库;然后分别使用决策树、分类关联规则等技术对视频属性数据库进行数据挖掘,提取出决策树分类规则集和分类关联规则集;最后利用一个规则集的合并裁减算法来合并这两个分类预测规则集,形成最终的具有更高精度的视频分类规则集。通过实验验证了决策树分类预测规则和分类关联规则具有分类预测的一致性;同时实验表明,使用合并后的规则集比单独使用一个规则集来预测视频具有更高的预测准确率。  相似文献   

4.
在信息化评估过程中,传统关联分类算法无法优先发现短规则,且分类精度对规则次序的依赖较强。为此,提出基于子集支持度和多规则分类的关联分类算法,将训练集按待分类属性归类,利用子集支持度挖掘关联规则,通过计算类平均支持度对测试集进行分类。实验结果表明,该算法发现规则的能力和分类精度均优于传统方法。  相似文献   

5.
针对基于规则推理技术(RBR)知识获取困难、自学习能力差等缺陷,将基于案例推理技术(CBR)引入故障诊断系统中。介绍了基于案例推理的故障诊断方法的工作机理和过程模型,阐述了案例表示、案例检索、案例保存和案例库维护机制,然后简单介绍了灰色关联理论知识,并把灰色关联理论应用到故障案例相似度的计算中。根据实验结果可知,该方法有效地改进了案例检索算法,提高了故障案例匹配的准确度和检索效率,同时具有较好的分辨率。  相似文献   

6.
基于CBR的交通事故处理智能决策支持系统   总被引:9,自引:1,他引:9  
依据智能化、集成化、协调化和网络化的设计准则,给出了基于CBR的交通事故处理智能决策支持系统的总体框架。并对该系统中的关键技术问题,基于案例推理的综合推理模型、典型案例库系统、人机智能系统分别进行了讨论。  相似文献   

7.
基于案例推理的入侵检测关联分析研究   总被引:1,自引:0,他引:1  
针对基于规则和模型的入侵检测专家系统中难以建立和表达入侵检测规则的问题,利用基于案例推理(CBR)方法对知识要求的低依赖性,将它引入入侵检测(ID)领域,提出了基于案例推理的入侵检测关联分析(CBRIDRA)模型的框架,研究了系统各功能模块,并对其中攻击案例定义、攻击案例检索、攻击案例管理、专家知识系统等关键技术的解决思路和实现方法进行了讨论。  相似文献   

8.
针对目前关联规则挖掘的数据集不断增大,而很多抽样算法精度不高还要解决一系列NP难问题等情况。在分析利用频繁1项集进行抽样处理的基础上,提出了高精度的基于频繁n项集平均划分的关联规则挖掘算法——EHAC算法。理论和实验都表明,EHAC能够提高数据挖掘精度,在数据平均划分的同时,尽量保证频繁n项集能够平均划分,减少了数据库扫描次数,一定程度上缩减了数据库规模。  相似文献   

9.
基于概念格的关联规则挖掘方法   总被引:3,自引:0,他引:3  
对概念格在关联规则挖掘中的应用进行了研究.通过将概念格的外延和内涵分别与事务数据库中的事务和特征相对应,可以从概念格上产生频繁项集,进而挖掘关联规则.提出了一种基于概念格的关联规则挖掘方法,在背景中对象约简的基础上,构造出对象约简后的概念格,从新的概念格中先产生基本规则集,再根据用户给出的支持度阈值从基本规则集中挖掘出对用户有意义的规则,并给出了算法描述.该方法求出的关联规则和利用Apriori算法求出的结果是一致的.  相似文献   

10.
灰度关联理论在CBR中的应用研究   总被引:2,自引:0,他引:2  
针对基于规则推理技术(RBR)知识获取困难、自学习能力差等缺陷,将基于案例推理技术(CBR)引入故障诊断系统中.介绍了基于案例推理的故障诊断方法的工作机理和过程模型,阐述了案例表示、案例检索、案例保存和案例库维护机制,然后简单介绍了灰色关联理论知识,并把灰色关联理论应用到故障案例相似度的计算中.根据实验结果可知,该方法有效地改进了案例检索算法,提高了故障案例匹配的准确度和检索效率,同时具有较好的分辨率.  相似文献   

11.
一种改进的案例推理分类方法研究   总被引:1,自引:0,他引:1  
张春晓  严爱军  王普 《自动化学报》2014,40(9):2015-2021
特征属性的权重分配和案例检索策略对案例推理(Case-based reasoning,CBR)分类的准确率有显著影响. 本文提出一种结合遗传算法、内省学习和群决策思想改进的CBR分类方法. 首先,利用遗传算法得到多组属性权重,再根据内省学习原理对每组权重进行迭代调整;然后,通过案例群检索策略得到满足大多数原则的群决策分类结果;最后,以典型分类数据集的对比实验证明了本文方法能进一步提高CBR分类的准确率. 这表明内省学习可以保证权重分配的合理性,案例群检索策略能充分利用案例库的潜在信息,对提升CBR的学习能力有显著作用.  相似文献   

12.
为了改善多目标评价案例推理设定模型在竖炉焙烧过程控制中的性能,运用注水原理分配过程变量的权重和群决策修正方法对多目标评价案例推理设定方法进行改进,得到一种新的智能设定模型.首先引入注水原理构造Lagrange函数对过程变量的权重进行优化分配,再通过案例检索和案例重用得到设定值的建议解,并根据多目标评价模型预测建议解对生产指标的影响效果,最后,对不合理的设定值进行群决策修正.将得到的设定模型应用于竖炉焙烧过程控制中,通过实验测试和对比应用说明了本文方法优于其他方法,能够有效提高多目标评价案例推理设定模型的控制性能.  相似文献   

13.
基于描述逻辑的事例推理(CBR)是当前CBR研究的热点之一。首先介绍了CBR的起源,然后回顾了基于描述逻辑的CBR的发展历史,接着从4个方面:事例表示与组织、事例检索、事例修正和事例库维护综述了基于描述逻辑的CBR的研究工作,最后指出了基于描述逻辑的CBR目前存在的问题并相应地提出了未来的研究方向。  相似文献   

14.
依据电渣重熔生产工艺特点、操作经验和历史数据库,提出了基于案例推理的电渣重熔生产过程智能 优化设定控制方法.采用粗糙集理论从积累的大量电渣重熔过程历史控制数据中获取知识,将典型工况总结成案例 的形式以构造案例库,并对案例推理过程中的案例检索、案例修正及存储方法进行详细描述.该智能控制策略应用 于某电渣重熔生产过程,稳定了电渣重熔过程工艺指标,取得了较好的应用效果.  相似文献   

15.
首先介绍了CBR(Case-based reasoning)推理中一个重要分支--基于文本案例的推理技术TCBR(Textual CBR)的产生背景.然后详细介绍了TCBR推理时采用的结构--实例提取网CRN(Case Retrieval Nets),描述案例的知识单元--信息实体的概念和特性,以及TCBR中如何进行实例提取、改编和学习.最后,对TCBR的改进研究、代表项目以及未来的发展方向作了概括性说明.  相似文献   

16.
Whenever there is any fault in an automotive engine ignition system or changes of an engine condition, an automotive mechanic can conventionally perform an analysis on the ignition pattern of the engine to examine symptoms, based on specific domain knowledge (domain features of an ignition pattern). In this paper, case-based reasoning (CBR) approach is presented to help solve human diagnosis problem using not only the domain features but also the extracted features of signals captured using a computer-linked automotive scope meter. CBR expert system has the advantage that it provides user with multiple possible diagnoses, instead of a single most probable diagnosis provided by traditional network-based classifiers such as multi-layer perceptions (MLP) and support vector machines (SVM). In addition, CBR overcomes the problem of incremental and decremental knowledge update as required by both MLP and SVM. Although CBR is effective, its application for high dimensional domains is inefficient because every instance in a case library must be compared during reasoning. To overcome this inefficiency, a combination of preprocessing methods, such as wavelet packet transforms (WPT), kernel principal component analysis (KPCA) and kernel K-means (KKM) is proposed. Considering the ignition signals captured by a scope meter are very similar, WPT is used for feature extraction so that the ignition signals can be compared with the extracted features. However, there exist many redundant points in the extracted features, which may degrade the diagnosis performance. Therefore, KPCA is employed to perform a dimension reduction. In addition, the number of cases in a case library can be controlled through clustering; KKM is adopted for this purpose. In this paper, several diagnosis methods are also used for comparison including MLP, SVM and CBR. Experimental results showed that CBR using WPT and KKM generated the highest accuracy and fitted better the requirements of the expert system.  相似文献   

17.
基于实例推理的智能刺绣编程系统   总被引:3,自引:0,他引:3  
本文介绍基于实例推理的智能刺绣编程系统。根据电脑刺绣领域问题的需要,建立了描述刺绣样品的实例模型,利用动态存储模型技术实现实例的存储和检索,在此基础上给出了基于实例的推理流程和算法、实例重用和实例保留算法等。基于实例推理方法可大大提高绣品的质量和刺绣编程的效率。  相似文献   

18.
Extended object model for product configuration design   总被引:1,自引:1,他引:0  
This paper presents an extended object model for case-based reasoning (CBR) in product configuration design. In the extended object model, a few methods of knowledge expression are adopted, such as constraints, rules, objects, etc. On the basis of extended object model, case representation model for CBR is applied to product configuration design system. The product configuration knowledge can be represented by the extended object. The model can support all the processes of CBR in product configuration design, such as case representation, indexing, retrieving, and case revising. The presented model is an extension of the traditional object-oriented model by including the relationship class used to express the relation between the cases, constraints class used in the product configuration knowledge representation, index class used in case retrieving, and solution class used in case revising. Therefore, the product configuration knowledge used in the product configuration design can be represented by using this model. In the end, a metering pump product configuration design system is developed on the basis of the proposed product configuration model to support customized products.  相似文献   

19.
Data mining for case-based reasoning in high-dimensional biological domains   总被引:1,自引:0,他引:1  
Case-based reasoning (CBR) is a suitable paradigm for class discovery in molecular biology, where the rules that define the domain knowledge are difficult to obtain and the number and the complexity of the rules affecting the problem are too large for formal knowledge representation. To extend the capabilities of CBR, we propose the mixture of experts for case-based reasoning (MOE4CBR), a method that combines an ensemble of CBR classifiers with spectral clustering and logistic regression. Our approach not only achieves higher prediction accuracy, but also leads to the selection of a subset of features that have meaningful relationships with their class labels. We evaluate MOE4CBR by applying the method to a CBR system called TA3 - a computational framework for CBR systems. For two ovarian mass spectrometry data sets, the prediction accuracy improves from 80 percent to 93 percent and from 90 percent to 98.4 percent, respectively. We also apply the method to leukemia and lung microarray data sets with prediction accuracy improving from 65 percent to 74 percent and from 60 percent to 70 percent, respectively. Finally, we compare our list of discovered biomarkers with the lists of selected biomarkers from other studies for the mass spectrometry data sets.  相似文献   

20.
Case-based reasoning and adaptation in hydraulic production machine design   总被引:13,自引:0,他引:13  
Case-based reasoning (CBR) can support hydraulic circuit design. Existing expert systems for hydraulic system design use production rules as its source of knowledge. However, this leads to problems of knowledge acquisition and knowledge base maintenance. This paper describes the application of CBR to hydraulic circuit design for production machines, which helps solving problems using past experience. A technique Case-based adaptation (CBA) is implemented in the adaptation stage of CBR so that adaptation becomes much easier. A prototype system has been developed to verify the usefulness of CBR and CBA in hydraulic production machines.  相似文献   

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