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1.
提出了一种改进的模糊分类系统的建模方法,采用模糊C均值聚类完成初始模糊分类系统的设计.提出改进的模糊规则置信度计算方法,对隶属函数和模糊规则相似度进行检测,剔除模糊规则中的冗余信息,利用遗传算法进行模糊分类系统的优化,提高系统的精确性和解释性.仿真结果证明了方法的有效性,对纤维图像的分类结果显示,该方法能获得与手工分类基本一致的分类结果.  相似文献   

2.
针对人工焊点缺陷识别方法进行研究,提出了一种基于特征聚集度的模糊C均值聚类(FCM)与松弛约束支持向量机(RSVM)联用的分类识别算法。在提取人工焊点特征向量的基础上,算法首先对样本特征数据进行模糊C均值聚类,依据样本隶属度函数计算不同特征的特征聚集度,并由特征聚集度指标改进RSVM算法中的松弛量参数,建立最终的分类器模型。实验结果表明:本文提出的算法建立了泛化能力更强的分类模型,能有效抑制噪声及模糊边界点对分类模型的影响,在人工焊点缺陷识别的应用中获得了满意的识别结果。  相似文献   

3.
根据补偿模糊神经网络的建模特点,提出了基于聚类和文化算法的补偿模糊神经网络建模方法。该网络的学习分为两步:结构辨识和参数辨识。在结构辨识中,采用改进的聚类算法确定模糊规则数及初始参数,构造一个初始模糊模型;在参数辨识中,采用基于多层信念空间的文化算法对具有5层结构的补偿模糊神经网络参数进一步优化,使其具有更高的精度。通过对TE过程的故障诊断建模,结果表明该网络在建模精度和收敛速度上均优于常规补偿模糊神经网络和常规模糊神经网络。  相似文献   

4.
基于案例的推理是人工智能中新崛起的一种重要推理技术,与医疗诊断具有较高的相似性.为实现病历案例的计算机表示和存储,采用框架和产生式表示法相结合,对非文本型数据,通过数组对方法进行转换.提出居于ICD10疾病分类的病历案例组织方法,整个案例库组成九大决策树.案例的检索采用启发式搜索策略,并定义估价函数为f(x,y)=(g(x),h(y)),模糊匹配算法通过对病历内容进行比较,在此基础上进行加权平均来实现,并通过约定的阈值α,以提高算法运算速度和使用价值.  相似文献   

5.
步态分类在人体运动能量消耗评估等应用中具有重要意义,提高分类精度和降低对统计特征的依赖是步态分类的研究热点。采用传统的步态分类方法提取的步态特征用于细分化步态时不能得到较好的效果。考虑到步态的连续性和不同轴之间信号的相关性,本文提出了基于CLSTM的步态分类方法:采用卷积神经网络(CNN)操作,通过计算多轴步态数据提取步态特征;基于长短期记忆(LSTM)构建步态时间序列模型,学习步态特征图时间维度上的长期依赖性。基于USC-HAD数据集的实验结果表明,用此方法提取了步态序列特征,很好地利用了步态时间序列特点,提升了11种步态的分类精度。  相似文献   

6.
针对高维输入小波网络的初始参数和网络结构非常复杂且计算量大的问题,提出用支持向量机(SVM)确定小波网络的初始参数和网络结构的方法。首先,使用有监督模糊聚类算法从聚类中抽取模糊规则,然后对每一个规则的后件使用支持向量机方法确定小波网络的结构和初始参数,最后采用梯度下降方法调节模糊小波网络中的参数,使得模糊小波网络输出与期望输出之间的误差较小。仿真结果表明:该算法与传统的模糊神经网络(FNN)相比显著提高了分类精度。  相似文献   

7.
将模糊聚类和模糊模式识别相结合的识别方法应用于具有多模糊特征变量的复合材料高温机械性能的识别中.对给定特征的复合材料进行模糊分类,建立群体模式.通过模糊模式识别在模式库中对检验样本进行匹配,实现对未知材料的聚类识别.结果表明:对于多因子相关的复合材料性能,两种方法的结合是有效可行的,可以满足经济性和准确性的要求.  相似文献   

8.
通过采集腿部肌肉5个通道的肌音信号,利用3层决策树对跑步、上楼、下楼、走路、静止5种步态动作进行模式识别研究。在决策树的第1层和第2层,应用双阈值门限法识别静止和跑步两种步态模式,在第3层,提出基于步态信号的自适应不等长分割算法以及改进的模糊熵算法,利用线性分类器对走路、上楼、下楼进行分类识别。结果表明:双门限阈值法可有效地对静止和跑步进行识别,当采用改进的模糊熵特征时,对走路、上楼、下楼3种步态模式的分类准确率达到了94.87%;而当综合利用近似熵、样本熵和改进的模糊熵3种特征时,其分类准确率达到了98.76%。  相似文献   

9.
基于粗糙集理论的知识约简方法和T-S模糊神经网络的非线性映射理论,针对回转窑烧结过程被控对象复杂、各参数之间相互耦合及难以建立精确数学模型的特点,提出一种RS-FNN智能控制策略。采用基于一种新的聚类有效性准则函数的模糊C均值聚类算法对连续属性进行离散化;然后利用粗糙集理论由历史数据样本提取约简规则集,对应的T-S模型具有反映数据特征的良好拓扑结构;最后T-S模型参数由梯度下降混合最小二乘法进行精调。该方法应用于铁矿氧化球团回转窑生产过程控制取得了良好效果,增强了系统容错及抗干扰的能力。  相似文献   

10.
大多数机器学习算法能得到较好的分类效果,但模型却无法解释;而随机森林等模型有良好的可解释性,却无法处理中医数据中兼证的情况。本文利用极值随机森林算法对慢性胃炎中医数据进行证候分类研究,其中决策树的叶节点能输出多个标签,通过加权机制综合分量来处理兼证问题。与已有多标记学习算法和C4.5、CART等基于决策树的算法进行比较,实验结果表明,极值随机森林算法无论在6个证型的分类准确率上,还是在多标记评价指标上都具有更好的效果,而且模型中得到的规则基本符合中医理论。  相似文献   

11.
12.
In the present paper, a fuzzy rule-based system (FRBS) is designed to serve as a decision support system for Coronary heart disease (CHD) diagnosis that not only considers the decision accuracy of the rules but also their transparency at the same time. To achieve the two above mentioned objectives, we apply a multi-objective genetic algorithm to optimize both the accuracy and transparency of the FRBS. In addition and to help assess the certainty and the importance of each rule by the physician, an extended format of fuzzy rules that incorporates the degree of decision certainty and importance or support of each rule at the consequent part of the rules is introduced. Furthermore, a new way for employing Ensemble Classifiers Strategy (ECS) method is proposed to enhance the classification ability of the FRBS. The results show that the generated rules are humanly understandable while their accuracy compared favorably with other benchmark classification methods. In addition, the produced FRBS is able to identify the uncertainty cases so that the physician can give a special consideration to deal with them and this will result in a better management of efforts and tasks. Furthermore, employing ECS has specifically improved the ability of FRBS to detect patients with CHD which is desirable feature for any CHD diagnosis system.  相似文献   

13.
郑小霞  钱锋 《医学教育探索》2006,(12):1458-1462
提出一种基于变精度粗糙-模糊集模型的诊断知识获取算法,利用相似性聚类方法自动获取模糊隶属函数,将连续属性表示成模糊值,通过定义模糊相似关系和模糊相似类给出了变精度粗糙-模糊模型的近似表示,并引入蚁群算法求取模糊相似关系下的属性约简,进行诊断知识的获取。将其应用于精对苯二甲酸生产过程尾氧浓度故障诊断知识获取中,结果表明:该算法可以从故障数据中提取更客观有效的诊断规则,在实际故障诊断中具有很好的应用价值。  相似文献   

14.
目的提出一种基于融合先验知识的肺结节深度学习分类方法。方法整体模型中包括图像特征提取子模型、语义提取子模型、语义整合子模型、多模态融合部分等。首先通过本文提出算法将医师标注语义信息转换为模糊one-hot码,然后将区域生长法设定不同阈值的输出图像输入语义提取子模型,模糊one-hot码作为多标签训练模型。最后将已训练语义提取子模型固定权重作为语义提取器置入整体模型中,输入图像分别经过图像特征提取子模型和语义提取子模型与语义整合子模型后通过融合输出预测结果。结果以公开数据集LIDC-IDRI作为实验数据做五折交叉验证,得出模型分类性能准确度88.32%、灵敏度81.86%、特异性93.37%、AUC 0.9220。结论基于融合先验知识的肺结节深度学习模型可较高性能实现肺结节良恶性诊断,可作为辅助影像医师诊断的有效工具。  相似文献   

15.
Coronary artery disease (CAD) is caused by atherosclerosis in coronary arteries and results in cardiac arrest and heart attack. For diagnosis of CAD, angiography is used which is a costly time consuming and highly technical invasive method. Researchers are, therefore, prompted for alternative methods such as machine learning algorithms that could use noninvasive clinical data for the disease diagnosis and assessing its severity. In this study, we present a novel hybrid method for CAD diagnosis, including risk factor identification using correlation based feature subset (CFS) selection with particle swam optimization (PSO) search method and K-means clustering algorithms. Supervised learning algorithms such as multi-layer perceptron (MLP), multinomial logistic regression (MLR), fuzzy unordered rule induction algorithm (FURIA) and C4.5 are then used to model CAD cases. We tested this approach on clinical data consisting of 26 features and 335 instances collected at the Department of Cardiology, Indira Gandhi Medical College, Shimla, India. MLR achieves highest prediction accuracy of 88.4 %.We tested this approach on benchmarked Cleaveland heart disease data as well. In this case also, MLR, outperforms other techniques. Proposed hybridized model improves the accuracy of classification algorithms from 8.3 % to 11.4 % for the Cleaveland data. The proposed method is, therefore, a promising tool for identification of CAD patients with improved prediction accuracy.  相似文献   

16.
This paper aims at identifying the factors that would help to diagnose acute myocardial infarction (AMI) using data from an electronic medical record system (EMR) and then generating structure decisions in the form of linguistic fuzzy rules to help predict and understand the outcome of the diagnosis. Since there is a tradeoff in the fuzzy system between the accuracy which measures the capability of the system to predict the diagnosis of AMI and transparency which reflects its ability to describe the symptoms-diagnosis relation in an understandable way, the proposed fuzzy rules are designed in a such a way to find an appropriate balance between these two conflicting modeling objectives using multi-objective genetic algorithms. The main advantage of the generated linguistic fuzzy rules is their ability to describe the relation between the symptoms and the outcome of the diagnosis in an understandable way, close to human thinking and this feature may help doctors to understand the decision process of the fuzzy rules.  相似文献   

17.
In this paper, attribute weighting method based on the cluster centers with aim of increasing the discrimination between classes has been proposed and applied to nonlinear separable datasets including two medical datasets (mammographic mass dataset and bupa liver disorders dataset) and 2-D spiral dataset. The goals of this method are to gather the data points near to cluster center all together to transform from nonlinear separable datasets to linear separable dataset. As clustering algorithm, k-means clustering, fuzzy c-means clustering, and subtractive clustering have been used. The proposed attribute weighting methods are k-means clustering based attribute weighting (KMCBAW), fuzzy c-means clustering based attribute weighting (FCMCBAW), and subtractive clustering based attribute weighting (SCBAW) and used prior to classifier algorithms including C4.5 decision tree and adaptive neuro-fuzzy inference system (ANFIS). To evaluate the proposed method, the recall, precision value, true negative rate (TNR), G-mean1, G-mean2, f-measure, and classification accuracy have been used. The results have shown that the best attribute weighting method was the subtractive clustering based attribute weighting with respect to classification performance in the classification of three used datasets.  相似文献   

18.
Liver-shape analysis and quantification is still an open research subject. Quantitative assessment of the liver is of clinical importance in various procedures such as diagnosis, treatment planning, and monitoring. Liver-shape classification is of clinical importance for corresponding intra-subject and inter-subject studies. In this research, we propose a novel technique for the liver-shape classification based on Spherical Harmonics (SH) coefficients. The proposed liver-shape classification algorithm consists of the following steps: (a) Preprocessing, including mesh generation and simplification, point-set matching, and surface to template alignment; (b) Liver-shape parameterization, including surface normalization, SH expansion followed by parameter space registration; (c) Feature selection and classification, including frequency based feature selection, feature space reduction by Principal Component Analysis (PCA), and classification. The above multi-step approach is novel in the sense that registration and feature selection for liver-shape classification is proposed and implemented and validated for the normal and diseases liver in the SH domain. Various groups of SH features after applying conventional PCA and/or ordered by p-value PCA are employed in two classifiers including Support Vector Machine (SVM) and k-Nearest Neighbor (k-NN) in the presence of 101 liver data sets. Results show that the proposed specific features combined with classifiers outperform existing liver-shape classification techniques that employ liver surface information in the spatial domain. In the available data sets, the proposed method can successful classify normal and diseased livers with a correct classification rate of above 90 %. The performed result in average is higher than conventional liver-shape classification method. Several standard metrics such as Leave-one-out cross-validation and Receiver Operating Characteristic (ROC) analysis are employed in the experiments and confirm the effectiveness of the proposed liver-shape classification with respect to conventional techniques.  相似文献   

19.
基于产生式规则,事例,模糊诊断,神经网络集成模式,提出了多参数综合智能故障诊断方法,分析了多种诊断方法集成的必要性,以及该方法的知识表示,智能推理诊断及知识学习,应用结果表明这一多参数综合智能故障诊断的方法在实际工程中是行之有效的。  相似文献   

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