Tennessee-Eastman过程的学习型案例推理故障诊断方法

为了提高Tennessee-Eastman(TE)过程的故障诊断准确率,本文研究一种学习型伪度量(learning pseudo metric,LPM)代替距离度量的案例检索方法,并建立了TE过程的案例推理(case-based reasoning,CBR)故障诊断模型.首先建立LPM度量准则并对LPM模型进行训练,其次度量目标案例与每一个源案例的相似度,从中检索与目标案例相似的同类案例,再采用多数重用原则从同类案例中决策出目标案例的解,最后通过TE过程的运行数据对该方法的性能进行测试,并与典型的CBR和BP(back-propagation)神经网络和支持向量机等方法进行对比,表明本文方法能有效提高故障诊断准确率,在实际化工过程中具有一定的推广应用价值.     

基于可信度阈值优化的案例推理评价分类方法

为了提高案例推理(CBR) 分类器的性能, 提出一种基于可信度阈值优化的CBR 评价分类方法. 首先, 通过一种可降低时间复杂度的改进型可信度评价策略对案例重用得到的建议解的可信度进行计算; 然后, 通过遗传算法(GA) 对可信度阈值进行迭代寻优; 接着, 根据得到的优化阈值将目标案例及其建议解划分为可信集或不可信集; 最后, 对不可信集按多数重用原则进行分类结论的调整, 从而实现可信的CBR 评价分类. 对比实验表明, 改进的可信度评价策略能有效提高分类性能, 从而可提高CBR分类器的决策与学习能力.

     

一种改进的案例推理分类方法研究

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.     

基于权重阈值寻优的案例推理分类器特征约简

为提高案例推(case-based reasoning,CBR)分类器的分类准确率并降低时间复杂度,本文提出了一种基于权重阈值寻优的特征约简策略.首先通过基于数据驱动的方法对特征权重进行分配,得到每个特征的权重结果;其次,设计特征权重重要度阈值的适应度函数,并利用遗传算法对该重要度阈值进行优化搜索,最后根据得到的优化阈值与特征的权重分配情况,删除权重小于该阈值的特征从而完成特征的约简过程.通过对比实验,本文所提策略能够有效提高CBR分类器的分类准确率并降低时间复杂度,表明了权重阈值寻优约简策略的可行性与优越性.验证了本文方法不仅可以降低CBR分类器的时间复杂度,而且能够提高CBR的决策与学习能力.     

Case-based reasoning and neural network based expert system for personalization

We suggest a hybrid expert system of case-based reasoning (CBR) and neural network (NN) for symbolic domain. In previous research, we proposed a hybrid system of memory and neural network based learning. In the system, the feature weights are extracted from the trained neural network, and used to improve retrieval accuracy of case-based reasoning. However, this system has worked best in domains in which all features had numeric values. When the feature values are symbolic, nearest neighbor methods typically resort to much simpler metrics, such as counting the features that match. A more sophisticated treatment of the feature space is required in symbolic domains.We propose feature-weighted CBR with neural network, which uses value difference metric (VDM) as distance function for symbolic features. In our system, the feature weight set calculated from the trained neural network plays the core role in connecting both the learning strategies. Moreover, the explanation on prediction can be given by presenting the most similar cases from the case base. To validate our system, illustrative experimental results are presented. We use datasets from the UCI machine learning archive for experiments. Finally, we present an application with a personalized counseling system for cosmetic industry whose questionnaires have symbolic features. Feature-weighted CBR with neural network predicts the five elements, which show customers’ character and physical constitution, with relatively high accuracy and expert system for personalization recommends personalized make-up style, color, life style and products.     

New knowledge extraction technique using probability for case-based reasoning: application to medical diagnosis

Abstract: Case-based reasoning (CBR) has been used in various problem-solving areas such as financial forecasting, credit analysis and medical diagnosis. However, conventional CBR has the limitation that it has no criterion for choosing the nearest cases based on the probabilistic similarity of cases. It uses a fixed number of neighbors without considering an optimal number for each target case, so it does not guarantee optimal similar neighbors for various target cases. This leads to the weakness of lowering predictability due to deviation from desired similar neighbors. In this paper we suggest a new case extraction technique called statistical case-based reasoning. The main idea involves a dynamic adaptation of the optimal number of neighbors by considering the distribution of distances between potential similar neighbors for each target case. In order to do this, our technique finds the optimal distance threshold and selects similar neighbors satisfying the distance threshold criterion. We apply this new method to five real-life medical data sets and compare the results with those of the statistical method, logistic regression; we also compare the results with the learning methods C5.0, CART, neural networks and conventional CBR. The results of this paper show that the proposed technique outperforms those of many other methods, it overcomes the limitation of conventional CBR, and it provides improved classification accuracy .     

Are case-based reasoning and dissimilarity-based classification two sides of the same coin?

Case-based reasoning (CBR) is used when generalized knowledge is lacking. The method works on a set of cases formerly processed and stored in the case base. A new case is interpreted based on its similarity to cases in the case base. The closest case with its associated result is selected and presented as output of the system. Recently, dissimilarity-based classification (DSC) has been introduced due to the curse of dimensionality of feature spaces and the problem arising when trying to make image features explicitly. The approach classifies samples based on their dissimilarity value to all training samples. In this paper we are reviewing the basic properties of these two approaches. We show the similarity of dissimilarity-based classification to case-based reasoning. Finally, we conclude that dissimilarity-based classification is a variant of case-based reasoning and that most of the open problems in dissimilarity-based classification are research topics of case-based reasoning.     

基于案例推理的谈判支持系统的研究

通过对谈判案例的表达、检索、复用、评价、适配和学习的研究,基于案例推理的谈判支持系统解决了谈判者谈判相关知识缺乏的问题;在谈判案例表达方法中提出了属性分类方法;采用改进的最近相邻法进行谈判案例适配,以获得更相近的谈判历史案例;通过对基于案例推理的谈判机制分析,构建了基于案例推理谈判支持系统的体系结构,并详细设计了谈判系统的功能.最后,通过一个采购谈判方案验证了基于案例推理谈判支持系统的实用性.     

提高案例推理分类器的可靠性研究

针对案例推理（Case-based reasoning,CBR）分类器的可靠性问题,本文提出一种改进的案例检索和案例重用方法. 首先在案例检索环节应用注水原理对属性权重进行优化分配,利用每个属性数据的标准差和均值构造拉格朗日函数求得属性权重,并设定重要度阈值指导属性约简;其次在案例重用环节引入基于可信度的重用策略,通过计算目标案例分属于各个类别的可信度大小来确定当前案例的分类结果. 最后通过实验对比,表明本文方法能有效提高分类精度和效率,分类器的可靠性得以保障.     

案例推理属性权重的分配模型比较研究

案例推理系统中各属性权重的赋值决定了案例之间的相似度 大小,进而对推理结果的正确与否产生显著影响.以属性加权K-最近邻 相似案例检索为基础,讨论了使用注水原理分配属性权重的机理,并通过建 立权重分配的合理性指标,构造拉格朗日函数对权重进行优 化求解,得到了收敛的注水分配算法.通过五折交叉的模式分类实验 ,分别对属性权重的平均分配法、注水分配算法和遗传算法分配法进行了比较研究,案例推理分类结果证明,在引入注水分配算法后,其分类性能得到有效改善.     

A case-based reasoning system with the two-dimensional reduction technique for customer classification

Many studies have tried to optimize parameters of case-based reasoning (CBR) systems. Among them, selection of appropriate features to measure similarity between the input and stored cases more precisely, and selection of appropriate instances to eliminate noises which distort prediction have been popular. However, these approaches have been applied independently although their simultaneous optimization may improve the prediction performance synergetically. This study proposes a case-based reasoning system with the two-dimensional reduction technique. In this study, vertical and horizontal dimensions of the research data are reduced through our research model, the hybrid feature and instance selection process using genetic algorithms. We apply the proposed model to a case involving real-world customer classification which predicts customers’ buying behavior for a specific product using their demographic characteristics. Experimental results show that the proposed technique may improve the classification accuracy and outperform various optimized models of the typical CBR system.     

基于智能CASE库的多时相SAR影像分类方法-土地利用及变化监测

针对SAR影像分类,提出了一种基于智能案例(CASE)库多时相SAR影像分类方法。该方法主要分为4部分:SAR影像预处理;智能CASE的建构;基于CASE相似度匹配的SAR影像分类;分类后处理。在智能CASE建构期间,引入时空分析技术去除“伪”CASE,从而保证了CASE库中CASE信息的可靠性。接着,在基于CASE匹配的SAR影像分类过程中,采用分层相似度评价的方法,消除CASE特征相互之间的混叠效应。最后,采用面向对象的方法进行影像分类后处理。该方法有效地考虑了分类地块的形状因子,使分类结果更精确、更符合逻辑性。以2000年(4景,包含4个季度)和2004年(3景,包含3个季度)的多时相SAR影像作为实验数据,结果表明,使用我们提出的方法能达到较好的SAR影像分类结果,分类总体精度达到85%～90%,这为利用多时相SAR影像实施土地利用和变化监测(Land Use and Land Cover Change,LULC)奠定了良好基础。     

Case learning for CBR-based collision avoidance systems

With the rapid development of case-based reasoning (CBR) techniques, CBR has been widely applied to real-world applications such as collision avoidance systems. A successful CBR-based system relies on a high-quality case base, and a case creation technique for generating such a case base is highly required. In this paper, we propose an automated case learning method for CBR-based collision avoidance systems. Building on techniques from CBR and natural language processing, we developed a methodology for learning cases from maritime affair records. After giving an overview on the developed systems, we present the methodology and the experiments conducted in case creation and case evaluation. The experimental results demonstrated the usefulness and applicability of the case learning approach for generating cases from the historic maritime affair records.     

范例推理技术在银行客户信用评估中的应用

范例推理技术是人工智能领域中一种基于知识的问题求解和学习方法。为了有效评估银行客户信用等级并提高银行信贷业务效率，文中提出了范例推理技术(CBR)在银行客户信用评估中的应用，并给出了基于范例推理的银行客户信用评估系统的原型，介绍了该系统中的关键技术：范例表示、相似性计算和范例检索，研究了归纳学习、特征子集选择等机器学习方法在范例检索中的应用。     

一种基于案例推理的多agent 强化学习方法研究

提出一种基于案例推理的多agent 强化学习方法．构建了系统策略案例库,通过判断agent 之间的协作 关系选择相应案例库子集．利用模拟退火方法从中寻找最合适的可再用案例策略,agent 按照案例指导执行动作选 择．在没有可用案例的情况下,agent 执行联合行为学习（JAL）．在学习结果的基础上实时更新系统策略案例库．追 捕问题的仿真结果表明所提方法明显提高了学习速度与收敛性．     

CFW的CBR与ART-KNN集成智能预测

结合基于案例推理（CBR）方法和ART-KNN网络，提出了一种黄瓜枯萎病（CFW）的集成智能预测方法。与传统的CBR相似案例检索任务不同的是，该方法用受训ART-KNN网络对新案例分类后根据提出的案例相似性测度来计算相似案例集。对ART-KNN网络的分类性能进行测试，确定了网络的最优相似参量ρ，得到最高平均分类正确率达94.4%。对CFW进行预测，确定了案例相异阈值R的最优范围，得到病株率、病叶率的最优平均预测误差率分别达7.4%、9.3%。综合分析结果表明，提出的CBR与ART-KNN集成预测方法可为CFW的防治提供较为可靠的预测数据以及辅助决策信息。     

TOWARD CASE-BASED REASONING FOR DIABETES MANAGEMENT: A PRELIMINARY CLINICAL STUDY AND DECISION SUPPORT SYSTEM PROTOTYPE

This paper presents a case-based decision support system prototype to assist patients with Type 1 diabetes on insulin pump therapy. These patients must vigilantly maintain blood glucose levels within prescribed target ranges to prevent serious disease complications, including blindness, neuropathy, and heart failure. Case-based reasoning (CBR) was selected for this domain because (a) existing guidelines for managing diabetes are general and must be tailored to individual patient needs; (b) physical and lifestyle factors combine to influence blood glucose levels; and (c) CBR has been successfully applied to the management of other long-term medical conditions. An institutional review board (IRB) approved preliminary clinical study, involving 20 patients, was conducted to assess the feasibility of providing case-based decision support for these patients. Fifty cases were compiled in a case library, situation assessment routines were encoded to detect common problems in blood glucose control, and retrieval metrics were developed to find the most relevant past cases for solving current problems. Preliminary results encourage continued research and work toward development of a practical tool for patients.     

基于等级相关的非分类案例检索

现有的非分类CBR（case-based reasoning）系统的对齐度量需要设定阈值,为了克服此局限,提出使用等级相关来判断一个案例是否符合CBR假设,据此给出了非分类CBR系统的评价指标,对加拿大交通安全局的55个航空事故调查报告进行实验,结果表明,使用等级相关对齐进行5-NN案例检索比使用比例对齐（case alignment）和加权相关（weighted correlation）这两个对齐度量,正确率分别提高了10.91%和16.37%。     

基于CBR的快速路VMS的信息发布策略

将案例推理技术引入到快速路上可变信息牌的信息发布策略中,利用以往具体案例的经验来解决当前新的信息发布问题.首先对北京市环路上可变信息牌的使用进行了评述,在此基础上提出了基于案例推理的快速路可变信息牌的信息发布策略.详细讨论了基于决策树的案例组织方法和基于模糊推理的案例修正方法.基于案例推理的信息发布策略能够及时准确地把相关信息发布给驾驶员,从而提高出行效率.     

Hybrid similarity measure for case retrieval in CBR and its application to emergency response towards gas explosion

Case retrieval is a primary step in case-based reasoning (CBR). It is important to measure the similarity between each historical case and the target case during the case retrieval process. In recent years, some methods for similarity measure with multiple formats of attribute values can be found in the practical CBR applications, but the in-depth study is still lacking. The objective of this paper is to develop a new method for hybrid similarity measure with five formats of attribute values: crisp symbols, crisp numbers, interval numbers, fuzzy linguistic variables and random variables. First, for each format of the attribute values, the calculation formula to measure the attribute similarity is presented. Then, the method for measuring hybrid similarity between each historical case and the target case is given by aggregating attribute similarities using the simple additive weighting method, and the proper historical case(s) can be retrieved according to the obtained hybrid similarities afterwards. Finally, a case study in the field of emergency response towards gas explosion is introduced to illustrate the use of the proposed method.