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1.
Our aim is to build an integrated learning framework of neural network and case-based reasoning. The main idea is that feature weights for case-based reasoning can be evaluated by neural networks. In this paper, we propose MBNR (Memory-Based Neural Reasoning), case-based reasoning with local feature weighting by neural network. In our method, the neural network guides the case-based reasoning by providing case-specific weights to the learning process. We developed a learning algorithm to train the neural network to learn the case-specific local weighting patterns for case-based reasoning. We showed the performance of our learning system using four datasets.  相似文献   

2.
片锦香  柴天佑  李界家 《自动化学报》2012,38(12):2032-2037
现有的卷取温度预报补偿模型和带钢批次间补偿模型中,由于案例推理(Case-based reasoning, CBR)系统中检索特征权重系数采用人工凑试的方法,难以获得满意的补偿作用,且由于缺乏迭代学习的初始工况条件的匹配算法,难以进行准确匹配和有效迭代.因此,本文针对这两个问题, 提出了基于神经网络技术的案例推理系统检索特征权重系数自动学习算法及迭代学习技术初始工况匹配算法,改进了卷取温度预报补偿模 型和带钢批次间补偿模型,并采用国内某大型钢厂的现场实际数据进行实验研究.实验结果表明,与原有方法相比,带钢卷取温度的控制偏差减小了1.63℃,卷取温度精度控制在±10℃以内的命中率提高了14.5%.  相似文献   

3.
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.  相似文献   

4.
Stress diagnosis based on finger temperature (FT) signals is receiving increasing interest in the psycho-physiological domain. However, in practice, it is difficult and tedious for a clinician and particularly less experienced clinicians to understand, interpret, and analyze complex, lengthy sequential measurements to make a diagnosis and treatment plan. The paper presents a case-based decision support system to assist clinicians in performing such tasks. Case-based reasoning (CBR) is applied as the main methodology to facilitate experience reuse and decision explanation by retrieving previous similar temperature profiles. Further fuzzy techniques are also employed and incorporated into the CBR system to handle vagueness, uncertainty inherently existing in clinicians reasoning as well as imprecision of feature values. Thirty-nine time series from 24 patients have been used to evaluate the approach (matching algorithms) and an expert has ranked and estimated similarity. On average goodness-of-fit for the fuzzy matching algorithm is 90% in ranking and 81% in similarity estimation that shows a level of performance close to an experienced expert. Therefore, we have suggested that a fuzzy matching algorithm in combination with CBR is a valuable approach in domains, where the fuzzy matching model similarity and case preference is consistent with the views of domain expert. This combination is also valuable, where domain experts are aware that the crisp values they use have a possibility distribution that can be estimated by the expert and is used when experienced experts reason about similarity. This is the case in the psycho-physiological domain and experienced experts can estimate this distribution of feature values and use them in their reasoning and explanation process.  相似文献   

5.
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   

6.
CBR与RBR相结合的实时专家系统设计与实现   总被引:12,自引:0,他引:12  
曲明  郝红卫 《计算机工程》2004,30(18):144-145,156
提出了一个基于案例的推理与基于规则的推理相结合的实时专家系统RTESCR,介绍了该系统原理及其组成部分。RTESCR主要适用于知识富有型应用领域,目前应用于航天控制系统实时故障诊断系统。  相似文献   

7.
用神经网络来实现基于范例的推理系统   总被引:9,自引:1,他引:9  
范例推理与神经网络有一种自然的联系,神经网络有许多优点,利用神经网络来实现范例推理可以取得非常好的效果。文章首先详细探讨了在范你推理中使用的神经网络模型与技术,并给出了其上的搜索与学习算法以及数据挖掘算法,旨在提高范例推理系统的鲁棒性和知识获取的自动化程度。  相似文献   

8.
基于混合智能的航天器故障诊断系统   总被引:1,自引:0,他引:1  
面向航天器测控管理,研究了一种基于专家系统(ES)、案例推理(CBR)以及故障树(FT)的混合智 能诊断技术.文中,故障树双向混合推理机制被用于实现航天器故障定位和预测.同时案例推理的k 最近邻检索 策略(KNN)采用了简单实用、易收敛特性的多感官群集算法(MSA).基于案例推理和故障树的航天器专家系 统(SESCF)采用了2 种融合模式.案例推理和故障树采用独立运行模式,专家系统与案例推理和故障树之间则采 用了松耦合运行模式.出于改善推理效率的目的,文中提出了一种将遥测信息转化为语义信息的结合特定推理方法 的非线性转换方法.某卫星供配电分系统的测试证实了SESCF 系统诊断的有效性.测试结果表明,相对于专家系 统,SESCF 系统具有更高的诊断准确度和可靠性.SESCF 系统采用的非线性转换方法在航天器故障诊断过程中简 单实用且容错性较好.  相似文献   

9.
Feature Weight Maintenance in Case Bases Using Introspective Learning   总被引:1,自引:0,他引:1  
A key issue in case-based reasoning is how to maintain the domain knowledge in the face of a changing environment. During the case retrieval process in case-based reasoning, feature-value pairs are used to compute the ranking scores of the cases in a case base, and different feature-value pairs may have different importance measures, represented as weight values, in this computation. How to maintain a set of appropriate feature weights so that they can be used to solve future problems effectively and efficiently will be a key factor in determining the success of case-based reasoning applications.Our focus in this paper is on the dynamic maintenance of feature weights in a case base. We address a particular problem related to the feature-weight maintenance issue. In current practice, the feature weights are assigned and revised manually, not only making them highly informal and inaccurate, but also involving intensive labor. We would like to introduce a semi-automatic introspective learning method to partially address this issue. Our approach is to construct a network architecture on the case base that supports introspective learning. Weight learning and weight-evolution are accomplished in the background through the integration of a learning network into case-based reasoning, in which, while the reasoning part is still case based, the learning part is shouldered by a layered network. The computation in the network follows well-known neural network algorithms with well known properties. We demonstrate the effectiveness of our approach through experiments.  相似文献   

10.
As modern business functions become more complex and knowledge-intensive, with increasing demands for quality services, there is an emerging trend for organisations to develop and deploy intelligent knowledge-based systems for mission-critical operations. Some of the challenges in successfully implementing this breed of systems depend on how well the intelligent system is integrated with conventional existing information systems and workflow, and the quality of the intelligent system itself. Developing quality expert systems lies in the effective modelling of cognitive processes of human experts and representation of various forms of related knowledge in a domain. An integrated intelligent system called the Intelligent Help Desk Facilitator (IHDF), has been developed for computer and network fault management. The system, which comprises various modules including an expert system, is successfully deployed in a problem response help desk environment of a local bank. This paper describes a cognitive-driven approach to the development of the expert system based on a hybrid knowledge representation and reasoning strategy. The approach incorporates a hybrid case-based reasoning (CBR) framework of techniques which include case memory organisation structures (discrimination networks and shared-featured networks), case indexing and retrieval schemes (fuzzy character-matching, nearest-neighbour similarity matching and knowledge-guided indexing); and an interactive and incremental style of reasoning. The paper discusses the design and implementation of the expert system component of IHDF and illustrates the appropriateness of the hybrid architecture for problem resolution and diagnostic types of applications.  相似文献   

11.
一种卷积神经网络和极限学习机相结合的人脸识别方法   总被引:1,自引:1,他引:0  
卷积神经网络是一种很好的特征提取器,但却不是最佳的分类器,而极限学习机能够很好地进行分类,却不能学习复杂的特征,根据这两者的优点和缺点,将它们结合起来,提出一种新的人脸识别方法。卷积神经网络提取人脸特征,极限学习机根据这些特征进行识别。本文还提出固定卷积神经网络的部分卷积核以减少训练参 数,从而提高识别精度的方法。在人脸库ORL和XM2VTS上进行测试的结果表明,本文的结合方法能有效提高人脸识别的识别率,而且固定部分卷积核的方式在训练样本少时具有优势。  相似文献   

12.
In this article, we introduce a personalized counseling system based on context mining. As a technique for context mining, we have developed an algorithm called CANSY. It adopts trained neural networks for feature weighting and a value difference metric in order to measure distances between all possible values of symbolic features. CANSY plays a core role in classifying and presenting most similar cases from a case base. Experimental results show that CANSY along with a rule base can provide personalized information with a relatively high level of accuracy, and it is capable of recommending appropriate products or services. An erratum to this article can be found at  相似文献   

13.
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.  相似文献   

14.
Although many knowledge-based systems (KBSs) focus on single-paradigm approaches to encoding knowledge (such as production rules), experts rarely use a single type of knowledge in solving a problem. More often, an expert will apply a number of reasoning mechanisms. In recent years, rule-based reasoning (RBR), case-based reasoning (CBR) and model-based reasoning (MBR) have emerged as important and complementary reasoning methodologies in artificial intelligence. For complex problem solving, it is useful to integrate RBR, CBR and MBR. In this paper, a hybrid KBS which integrates a deductive RBR system, an inductive CBR system and a quantitative MBR system is proposed for epidemic screening. The system has been tested using real data, and results are encouraging.  相似文献   

15.
A hybrid approach of neural network and memory-based learning todata mining   总被引:4,自引:0,他引:4  
We propose a hybrid prediction system of neural network and memory-based learning. Neural network (NN) and memory-based reasoning (MBR) are frequently applied to data mining with various objectives. They have common advantages over other learning strategies. NN and MBR can be directly applied to classification and regression without additional transformation mechanisms. They also have strength in learning the dynamic behavior of the system over a period of time. Unfortunately, they have shortcomings when applied to data mining tasks. Though the neural network is considered as one of the most powerful and universal predictors, the knowledge representation of NN is unreadable to humans, and this "black box" property restricts the application of NN to data mining problems, which require proper explanations for the prediction. On the other hand, MBR suffers from the feature-weighting problem. When MBR measures the distance between cases, some input features should be treated as more important than other features. Feature weighting should be executed prior to prediction in order to provide the information on the feature importance. In our hybrid system of NN and MBR, the feature weight set, which is calculated from the trained neural network, plays the core role in connecting both learning strategies, and the explanation for prediction can be given by obtaining and presenting the most similar examples from the case base. Moreover, the proposed system has advantages in the typical data mining problems such as scalability to large datasets, high dimensions, and adaptability to dynamic situations. Experimental results show that the hybrid system has a high potential in solving data mining problems.  相似文献   

16.
The exploration of three-dimensional (3D) anthropometry scanning data along with other existing subject medical profiles using data mining techniques becomes an important research issue for medical decision support. This research attempts to construct a classification approach based on the hybrid use of case-based reasoning (CBR) and genetic algorithms (GAs) for hypertension detection using anthropometric body surface scanning data. The obtained result reveals the relationship between a subject’s 3D scanning data and hypertension disease. The GA is adopted to determine the appropriate feature weights for CBR. The proposed approaches were experimented and compared with a regular CBR and other widely used approaches including neural nets and decision trees. The experiment showed that applying GA to determine the suitable weights in CBR is a feasible approach to improving the effectiveness of case matching of hypertension disease. It also demonstrated that different weighted CBR approach presents better classification accuracy over the results obtained from other approaches.  相似文献   

17.
Although many knowledge-based systems (KBSs) focus on single-paradigm approaches to encoding knowledge (such as production rules), human experts rarely use a single type of knowledge to solve a real-world problem. A human expert usually combines a number of reasoning mechanisms. In recent years, rule-based reasoning (RBR), case-based reasoning (CBR) and model-based reasoning (MBR) have emerged as important and complementary reasoning methodologies in the intelligent systems area. For complex problem solving, it is useful to integrate RBR, CBR and MBR. In this paper, a hybrid epidemic screening KBS which integrates a deductive RBR system, an inductive CBR system and a quantitative MBR system is proposed. The system has been tested using real epidemic screening variables and data.  相似文献   

18.
基于多层前馈神经网络的案例推理系统   总被引:2,自引:0,他引:2  
采用基于该神经网络技术的案例推理系统,使用交叉覆盖算法,可兰亨登地缩减案例的检索时间、减少案例适应性修改、提高推磊效率。实验表明该系统易于设计构建,极大地提升了CBR在实际中的应用能力。  相似文献   

19.
Development of classification methods using case-based reasoning systems is an active area of research. In this paper, two new case-based reasoning systems with two similarity measures that support mixed categorical and numerical data as well as only categorical data are proposed. The principal difference between these two measures lies in the calculations of distance for categorical data. The first one, named distance in unsupervised learning (DUL), is derived from co-occurrence of values, and the other one, named distance in supervised learning (DSL), is used to calculate the distance between two values of the same feature with respect to every other feature for a given class. However, the distance between numerical data is computed using the Euclidean distance. Furthermore, the importance of numeric features is determined by linear discrimination analysis (LDA) and the weight assignment to categorical features depends on co-occurrence of feature values when calculating the similarity between a new case and the old one. The performance of the proposed case-based reasoning systems has been investigated on the University of California, Irvine (UCI) data sets by 5-fold cross validation. The results indicate that these case-based reasoning systems will produce a proper performance in predictive accuracy and interpretability.  相似文献   

20.
针对锌湿法冶炼净化过程的复杂性,提出了一种结合粒子群算法和案例推理方法的净化过程Ⅱ段出口钴离子浓度混杂预测模型.考虑到不同时期案例所起的作用不一样,提出了一种综合加权相似函数.针对案例推理方法中属性权重选择和近邻个数的选取问题,提出了带有变异的惯性权重自适应粒子群算法优化方法,优化最近邻算法中特征权重矢量和近邻数,提高案例的检索精度.以净化过程生产数据进行实验验证和对比分析,计算结果表明改进的案例推理模型精度优于神经网络模型,模型预测结果可以作为过程信息用于净化过程的优化控制.  相似文献   

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