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1.
Brain tumor classification and retrieval system plays an important role in medical field. In this paper, an efficient Glioma Brain Tumor detection and its retrieval system is proposed. The proposed methodology consists of two modules as classification and retrieval. The classification modules are designed using preprocessing, feature extraction and tumor detection techniques using Co‐Active Adaptive Neuro Fuzzy Inference System (CANFIS) classifier. The image enhancement can be achieved using Heuristic histogram equalization technique as preprocessing and further texture features as Local Ternary Pattern (LTP) features and Grey Level Co‐occurrence Matrix (GLCM) features are extracted from the enhanced image. These features are used to classify the brain image into normal and abnormal using CANFIS classifier. The tumor region in abnormal brain image is segmented using normalized graph cut segmentation algorithm. The retrieval module is used to retrieve the similar segmented tumor regions from the dataset for diagnosing the tumor region using Euclidean algorithm. The proposed Glioma Brain tumor classification methodology achieves 97.28% sensitivity, 98.16% specificity and 99.14% accuracy. The proposed retrieval system achieves 97.29% precision and 98.16% recall rate with respect to ground truth images.  相似文献   

2.
针对早期火灾信息特点,提出了一种基于二叉树的最小二乘小波支持向量机(Least squareswavelet support vector machine,LS-WSVM)多类分类方法.该方法首先把主成份分析用于早期火灾信息的特征提取.然后,把二叉树结构和LS-WSVM相结合,提出了基于二叉树的LS-WSVM多类分类模型,不仅避免了盲目分类和不可分情况,而且提高了分类速度和泛化能力.最后,用该模型对特征信息进行处理,从而实现了对早期火灾的多类识别.早期火灾分类实验结果表明,该方法比采用径向基核函数的最小二乘支持向量机多类分类方法具有更好的识别效果和更快的分类速度.  相似文献   

3.
Several researchers are trying to develop different computer-aided diagnosis system for breast cancer employing machine learning (ML) methods. The inputs to these ML algorithms are labeled histopathological images which have complex visual patterns. So, it is difficult to identify quality features for cancer diagnosis. The pre-trained Convolutional Neural Networks (CNNs) have recently emerged as an unsupervised feature extractor. However, a limited investigation has been done for breast cancer recognition using histopathology images with CNN as a feature extractor. This work investigates ten different pre-trained CNNs for extracting the features from breast cancer histopathology images. The breast cancer histopathological images are obtained from publicly available BreakHis dataset. The classification models for the different feature sets, which are obtained using different pre-trained CNNs in consideration, are developed using a linear support vector machine. The proposed method outperforms the other state of art methods for cancer detection, which can be observed from the results obtained.  相似文献   

4.
在计算机辅助设计(computer aided design,CAD)中,对机械零件的三维模型进行分类和检索有利于设计人员重用设计信息,从而缩短产品的开发周期,以快速响应市场需求。针对三维模型的分类与检索,提出了一种基于极半径曲面矩和隐马尔科夫模型(hidden Markov model,HMM)的分类与检索算法。首先,计算三维模型的极半径曲面矩并组成特征向量,经排序编码后,将其作为HMM的观测序列;然后,取一部分人工标注过的三维模型作为训练样本,采用添加比例因子的多观测序列B-W(Baum-Welch)算法对HMM进行训练;最后,利用训练好的HMM对三维模型进行分类与检索。实验结果显示,与现有的2种分类与检索算法相比,所提出的算法具有更高的识别率和检索效率。该算法的特点是:极半径曲面矩计算快,不用将三维模型体素化;HMM训练快,分类能力强,且不需要大量训练样本就有一定的分类能力。研究表明,所提出的算法能较好地解决三维模型的分类与检索问题,具有一定的实用价值。  相似文献   

5.
6.
Prediction of cardiovascular disease (CVD) is a critical challenge in the area of clinical data analysis. In this study, an efficient heart disease prediction is developed based on optimal feature selection. Initially, the data pre‐processing process is performed using data cleaning, data transformation, missing values imputation, and data normalisation. Then the decision function‐based chaotic salp swarm (DFCSS) algorithm is used to select the optimal features in the feature selection process. Then the chosen attributes are given to the improved Elman neural network (IENN) for data classification. Here, the sailfish optimisation (SFO) algorithm is used to compute the optimal weight value of IENN. The combination of DFCSS–IENN‐based SFO (IESFO) algorithm effectively predicts heart disease. The proposed (DFCSS–IESFO) approach is implemented in the Python environment using two different datasets such as the University of California Irvine (UCI) Cleveland heart disease dataset and CVD dataset. The simulation results proved that the proposed scheme achieved a high‐classification accuracy of 98.7% for the CVD dataset and 98% for the UCI dataset compared to other classifiers, such as support vector machine, K‐nearest neighbour, Elman neural network, Gaussian Naive Bayes, logistic regression, random forest, and decision tree.Inspec keywords: cardiovascular system, medical diagnostic computing, feature extraction, regression analysis, data mining, learning (artificial intelligence), Bayes methods, neural nets, support vector machines, diseases, pattern classification, data handling, decision trees, cardiology, data analysis, feature selectionOther keywords: efficient heart disease prediction‐based, optimal feature selection, improved Elman‐SFO, cardiovascular disease, clinical data analysis, data pre‐processing process, data cleaning, data transformation, values imputation, data normalisation, decision function‐based chaotic salp swarm algorithm, optimal features, feature selection process, improved Elman neural network, data classification, sailfish optimisation algorithm, optimal weight value, DFCSS–IENN‐based SFO algorithm, DFCSS–IESFO, California Irvine Cleveland heart disease dataset, CVD dataset, high‐classification accuracy  相似文献   

7.
提出一种新的用于风机故障诊断的免疫克隆特征选择算法.提取了生产线上实测风机噪声的时域波形结构特征、小波分析特征及听觉谱特征,进行特征选择和故障诊断仿真实验.实验结果表明:在特征选择后的特征数目比原特征数目减少61% 的情况下,支持向量机分类器的分类正确率下降很小,分类时间显著减少.实验结果证明了该算法的有效性和鲁棒性,且能有效地应用于风机故障诊断.  相似文献   

8.
基于谱相关密度切片分析和SVM的滚动轴承故障诊断   总被引:1,自引:1,他引:0       下载免费PDF全文
明阳  陈进 《振动与冲击》2010,29(1):196-199
为了对旋转机械中的滚动轴承进行故障分析,针对滚动轴承具有二阶循环平稳的特点,采用了谱相关密度组合切片分析方法进行特征提取,并将提取的特征作为输入向量,用"一对其他"多分类支持向量机进行故障识别,给出了基于谱相关密度组合切片分析和多类支持向量机的滚动轴承故障诊断流程图,该方法具有较高的计算效率和估计精度。最后通过对实验数据的分析与处理,验证了该方法在滚动轴承故障诊断中的可行性和实用价值。  相似文献   

9.
针对磁瓦生产过程中表面缺陷检测的重要性和人工检测的弊端,研究基于机器视觉的磁瓦表面缺陷自动检测与识别方法.为解决磁瓦表面缺陷种类多、对比度低、图像中存在磨痕纹理背景和整体亮度不均匀等难点,定义扫描线梯度,其标准差与扫描线灰度标准差构成特征向量,提出基于两类支持向量机的图像分割方法来判别和提取缺陷;并提出一种改进的多类支持向量机方法,对缺陷进行分类识别,解决了多类支持向量机存在不可分区域的问题,提高了分类器的准确性和有效性.实验结果表明,该方法能准确快速地提检测磁瓦表面各区域的各类缺陷,检出率可达到96%以上,识别率超过91%.  相似文献   

10.
The benefits of applying automated fault detection and diagnosis (AFDD) to chillers include less expensive repairs, timely maintenance, and shorter downtimes. This study employs feature selection (FS) techniques, such as mutual-information-based filter and genetic-algorithm-based wrapper, to help search for the important sensors in data driven chiller FDD applications, so as to improve FDD performance while saving initial sensor cost. The ‘one-against-one’ multi-class support vector machine (SVM) is adopted as a FDD tool. The results show that the eight features/sensors, centered around the core refrigeration cycle and selected by the GA-SVM wrapper from the original 64 features, outperform the other three feature subsets by the GA-LDA (linear discriminant analysis) wrapper, with an overall classification correct rate (CR) as high as 99.53% for the 4000 test samples randomly covering the normal and seven typical faulty modes. The CRs for the four cases with FS are all higher than that without FS (97.45%) and the test time is much less, about 28-36%. The FDD performance for normal or each of the faulty modes is also evaluated in details in terms of hit rate (HR) and false alarm rate (FAR).  相似文献   

11.
水声目标识别是被动声呐系统的主要应用之一。为了进一步提升小样本条件下水下目标的识别率,文章提出一种基于多尺度卷积和双端注意力机制相融合的方法。首先,提取梅尔倒谱系数,色度谱和计算谱对比度等特征,建立基于多类别特征子集的三维聚合特征。其次,采用多尺度卷积滤波器算子构造多分辨率卷积神经网络,以更好地适应三维聚合特征的时频结构。另外,采用双端注意力模型捕获样本的全局依赖和局部特性。采用基于指数加权的对数交叉熵函数作为损失函数,提升样本数较少类别的识别率。实验结果表明,该方法在ShipsEar数据上的平均识别率为95.5%,取得了较好的分类效果。  相似文献   

12.
The endoscopy procedure has demonstrated great efficiency in detecting stomach lesions, with extensive numbers of endoscope images produced globally each day. The content‐based gastric image retrieval (CBGIR) system has demonstrated substantial potential in gastric image analysis. Gastric precancerous diseases (GPD) have higher prevalence in gastric cancer patients. Thus, effective intervention is crucial at the GPD stage. In this paper, a CBGIR method is proposed using a modified ResNet‐18 to generate binary hash codes for a rapid and accurate image retrieval process. We tested several popular models (AlexNet, VGGNet and ResNet), with ResNet‐18 determined as the optimum option. Our proposed method was valued using a GPD data set, resulting in a classification accuracy of 96.21 ± 0.66% and a mean average precision of 0.927 ± 0.006 , outperforming other state‐of‐art conventional methods. Furthermore, we constructed a Gastric‐Map (GM) based on feature representations in order to visualize the retrieval results. This work has great auxiliary significance for endoscopists in terms of understanding the typical GPD characteristics and improving aided diagnosis.  相似文献   

13.
In the era of Big data, learning discriminant feature representation from network traffic is identified has as an invariably essential task for improving the detection ability of an intrusion detection system (IDS). Owing to the lack of accurately labeled network traffic data, many unsupervised feature representation learning models have been proposed with state-of-the-art performance. Yet, these models fail to consider the classification error while learning the feature representation. Intuitively, the learnt feature representation may degrade the performance of the classification task. For the first time in the field of intrusion detection, this paper proposes an unsupervised IDS model leveraging the benefits of deep autoencoder (DAE) for learning the robust feature representation and one-class support vector machine (OCSVM) for finding the more compact decision hyperplane for intrusion detection. Specially, the proposed model defines a new unified objective function to minimize the reconstruction and classification error simultaneously. This unique contribution not only enables the model to support joint learning for feature representation and classifier training but also guides to learn the robust feature representation which can improve the discrimination ability of the classifier for intrusion detection. Three set of evaluation experiments are conducted to demonstrate the potential of the proposed model. First, the ablation evaluation on benchmark dataset, NSL-KDD validates the design decision of the proposed model. Next, the performance evaluation on recent intrusion dataset, UNSW-NB15 signifies the stable performance of the proposed model. Finally, the comparative evaluation verifies the efficacy of the proposed model against recently published state-of-the-art methods.  相似文献   

14.
针对不同故障类别齿轮的故障信息难以有效获取、齿面多类故障难以准确聚类的问题,提出一种基于特征处理的最大方差展开(Maximum Variance Unfolding,MVU)维数简约的齿轮故障诊断模型。首先对获取的振动信号进行最小熵反卷积(Minimum Entropy Deconvolution,MED)预处理,将高低频段进行分离并筛除不确定信号,并在多域上提取信息熵作为特征指标;而后,利用样本点分布矩阵筛选高效表征特征指标并构建高维特征空间,并利用改进的MVU算法对其进行维数简约,获取低维的真实子空间;最后,将其输入到超球多类支持向量机中进行超球构造与分类识别。通过实验数据的分析对比验证模型的有效性。  相似文献   

15.
Content-based video retrieval system aims at assisting a user to retrieve targeted video sequence in a large database. Most of the search engines use textual annotations to retrieve videos. These types of engines offer a low-level abstraction while the user seeks high-level semantics. Bridging this type of semantic gap in video retrieval remains an important challenge. In this paper, colour, texture and shapes are considered to be low-level features and motion is a high-level feature. Colour histograms convert the RGB colour space into YcbCr and extract hue and saturation values from frames. After colour extraction, filter mask is applied and gradient value is computed. Gradient and threshold values are compared to draw the edge map. Edges are smoothed for sharpening to remove the unnecessary connected components. These diverse shapes are then extracted and stored in shape feature vectors. Finally, an SVM classifier is used for classification of low-level features. For high-level features, depth images are extracted for motion feature identification and classification is done via echo state neural networks (ESN). ESN are a supervised learning technique and follow the principle of recurrent neural networks. ESN are well known for time series classification and also proved their effective performance in gesture detection. By combining the existing algorithms, a high-performance multimedia event detection system is constructed. The effectiveness and efficiency of proposed event detection mechanism is validated using MSR 3D action pair dataset. Experimental results show that the detection accuracy of proposed combination is better than those of other algorithms  相似文献   

16.
The study presented in this paper investigated the possibility of using support vector machine (SVM) models for crash injury severity analysis. Based on crash data collected at 326 freeway diverge areas, a SVM model was developed for predicting the injury severity associated with individual crashes. An ordered probit (OP) model was also developed using the same dataset. The research team compared the performance of the SVM model and the OP model. It was found that the SVM model produced better prediction performance for crash injury severity than did the OP model. The percent of correct prediction for the SVM model was found to be 48.8%, which was higher than that produced by the OP model (44.0%). Even though the SVM model may suffer from the multi-class classification problem, it still provides better prediction results for small proportion injury severities than the OP model does.  相似文献   

17.
周勇  何创新 《振动与冲击》2012,31(3):157-161
在线状态监控与故障诊断具有很大的经济与安全意义,提出了一种基于独立特征选择(IFS)与相关向量机(RVM)的智能故障诊断模型用于变载荷条件下识别多类轴承故障及其故障程度。首先混合空载(0hp)与满载(3hp)两种载荷状态下的实验数据作为训练样本;其次提取时域统计特征与全小波包域节点能量特征作为候选特征;接着采用一种改进的Fisher特征选择方法为每两类故障状态独立选择具有最大分类能力的最优特征子集;然后用“一对一”的方法训练多个RVM二类子分类器;最后采用“最大概率赢”的策略组合所有子分类器构成IFS_RVM多类故障诊断模型。用未知载荷(1hp,2hp)下的实验数据验证了模型的有效性,得到99.58%的极高诊断精度,实验结果表明,该模型精度高、鲁棒性强,满足变载荷条件下在线故障诊断的需要  相似文献   

18.
Common spatial pattern (CSP) is a widely adopted method for electroencephalogram (EEG) feature extraction in brain-computer interface (BCI) based on motor imagery. Bandpass-filtering EEG into several subbands related to brain activity tasks is an effective approach to improve the performance of CSP based algorithm. However, this approach tends to suffer the over-fitting problem because of the increase in feature dimension. Therefore, we proposed an optimal channel and frequency band-based CSP feature selection method in this paper. Firstly, the correlation coefficient was calculated to select the optimal channels, and these channels were bandpass-filtered into multiple overlapping subbands. The subbands with higher power spectrum density were chosen for CSP feature extraction. Next, the pair-wise relevance was utilized to remove subband features with less difference. And then the screened subband features were combined with features extracted from the broadband signal. The Fisher ratio was exploited to carry out further feature selection. Finally, a support vector machine (SVM) was trained to classify the selected CSP features. An experimental study was implemented on BCI competition III dataset IVa and BCI competition IV dataset 1. The average classification accuracy reached 89.33% and 84.08%, which indicated the rationality and effectiveness of the proposed method.  相似文献   

19.
Lung cancer is a critical disease with growing death rate, hence, the faster identification and treatment of lung cancer is essential. In medical image processing, the traditional methods like support vector machine, relevance vector machine for classifying cancer tissues are less sensitive to false data and required optimal improvement in classification accuracy. The proposed system of accurate lung cancer classification is obtained by a hybrid fuzzy relevance vector machine (FRVM) classifier with correlation negation ant colony optimization (CNACO) algorithm. This system provides enhanced accuracy and sensitivity by implementing two stages of feature extraction, image thresholding, and tumor segmentation, with a novel feature selection and tumor classification algorithm. The best features are selected by the proposed CNACO algorithm. The selected features are labeled and classified by FRVM classifier. The proposed classification scheme is validated on lung image database consortium and image database resource initiative public database and obtained accuracy of about 98.75%.  相似文献   

20.
Fully convolutional networks (FCNs) take the input of arbitrary size and produce correspondingly sized output with efficient inference and learning. The automatic diagnosis of melanoma is very essential for reducing the mortality rate by identifying the disease in earlier stages. A two-stage framework is used for implementing the melanoma detection, segmentation of skin lesion, and identification of melanoma lesions. Two FCNs based on VGG-16 and GoogLeNet are incorporated for improving the segmentation accuracy. A hybrid framework is used for incorporating these two FCNs. The classification is done by extracting the feature from segmented lesion by using deep residual network and a hand-crafted feature. Classification is done by support vector machine. The performance analysis of our framework gives a promising accuracy, that is, 0.8892 for classification in ISBI 2016 dataset and 0.853 for ISIC 2017 dataset.  相似文献   

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