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1.
基于深度卷积神经网络的图像检索算法研究   总被引:2,自引:0,他引:2  
为解决卷积神经网络在提取图像特征时所造成的特征信息损失,提高图像检索的准确率,提出了一种基于改进卷积神经网络LeNet-L的图像检索算法。首先,改进LeNet-5卷积神经网络结构,增加网络结构深度。然后,对深度卷积神经网络模型LeNet-L进行预训练,得到训练好的网络模型,进而提取出图像高层语义特征。最后,通过距离函数比较待检图像与图像库的相似度,得出相似图像。在Corel数据集上,与原模型以及传统的SVM主动学习图像检索方法相比,该图像检索方法有较高的准确性。经实验结果表明,改进后的卷积神经网络具有更好的检索效果。  相似文献   

2.

Manuel brain glioblastomas tumor exploration through MRI modalities is time-consuming. It is considered as a harmful and critical task due to highly inhomogeneous tumor regions composition. For this reason, clinicians recommend the Computer-Aided Diagnosis (CAD) tools to ensure a more accurate diagnostic. Based on convolutional Deep-Learning algorithms, this paper investigates a fully automatic CAD for brain Glioblastomas tumors exploration including three steps: pre-processing, segmentation, and finally classification. A denoising and an automatic contrast enhancement method have been applied to preprocess the MRI scans. A Multi-Modal Cascaded U-net architecture, based on Fully Convolutional deep Network (FCN), has been adopted for the Region of Interest (ROI) extraction and finally, Deep Convolutional Neural Network (D-CNN) architecture has been used to classify brain glioblastomas tumor into High-Grade (HG) and Low-Grade (LG). Experiments were performed on the Multimodal Brain Tumor Segmentation Challenge BraTS-2018 datasets benchmark. Several validations metric have been adopted to assess the CAD’s performances. The Dice Metric (DM) parameter has been calculated between the obtained segmentation results and the available ground truth data. The accuracy parameter has been computed for classification performance evaluation. The higher DM and accuracy values could attest the performance and the efficiency of the proposed CAD tool.

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3.
Zhang  Jianming  Liu  Yang  Liu  Hehua  Wang  Jin  Zhang  Yudong 《Applied Intelligence》2022,52(6):6129-6147
Applied Intelligence - In recent years, the ensembled trackers composed of multi-level features from the pre-trained Convolutional Neural Network (CNN) have achieved top performance in visual...  相似文献   

4.
A Computer-Aided Diagnostic (CAD) system that uses Artificial Neural Network (ANN) trained by drawing in the relative advantages of Differential Evolution (DE), Particle Swarm Optimization (PSO) and gradient descent based backpropagation (BP) for classifying clinical datasets is proposed. The DE algorithm with a modified best mutation operation is used to enhance the search exploration of PSO. The ANN is trained using PSO and the global best value obtained is used as a seed by the BP. Local search is performed using BP, in which the weights of the Neural Network (NN) are adjusted to obtain an optimal set of NN weights. Three benchmark clinical datasets namely, Pima Indian Diabetes, Wisconsin Breast Cancer and Cleveland Heart Disease, obtained from the University of California Irvine (UCI) machine learning repository have been used. The performance of the trained neural network classifier proposed in this work is compared with the existing gradient descent backpropagation, differential evolution with backpropagation and particle swarm optimization with gradient descent backpropagation algorithms. The experimental results show that DEGI-BP provides 85.71% accuracy for diabetes, 98.52% for breast cancer and 86.66% for heart disease datasets. This CAD system can be used by junior clinicians as an aid for medical decision support.  相似文献   

5.
本论文针对乳腺癌病理图像分析提出新的方法进行图像特征提取和可疑区域标记。由于深度神经网络,例如 VGG,GoogleNet,ResNet 等,均需要大量的标注样本才能完成训练,而医疗影像图像的标记成本很高,并不能为训练复杂的网络提供足够的训练数据。本论文借鉴生成对抗网络(Generative Adversarial Network, GAN) 的思想,提出基于弱监督学习的病理图像可疑区域标记网络,首先利用少量有标记的病理图像数据来训练分类模型,即判断该图像是否是乳腺癌,然后通过融合该网络提取到的具有判别力的特征来对可疑区域进行标记。由本文提出的网络在已有的国外乳腺癌病理图像数据集上达到的平均准确率为 83.8%,比基于卷积神经网络 (Convolutional Neural Network,CNN) 的分类方法在准确率上分别高 3 个百分点,说明该网络提取到的特征具有更好的判别力,不仅能够提高分类模型的准确率,还更有助于对病理图像的可疑区域进行标记。  相似文献   

6.
组织病理学图像是鉴别乳腺癌的黄金标准,所以对乳腺癌组织病理学图像的自动、精确的分类具有重要的临床应用价值。为了提高乳腺组织病理图像的分类准确率,从而满足临床应用的需求,提出了一种融合空间和通道特征的高精度乳腺癌分类方法。该方法使用颜色归一化来处理病理图像并使用数据增强扩充数据集,基于卷积神经网络(CNN)模型DenseNet和压缩和激励网络(SENet)融合病理图像的空间特征信息和通道特征信息,并根据压缩-激励(SE)模块的插入位置和数量,设计了三种不同的BCSCNet模型,分别为BCSCNetⅠ、BCSCNetⅡ、BCSCNetⅢ。在乳腺癌癌组织病理图像数据集(BreaKHis)上展开实验。通过实验对比,先是验证了对图像进行颜色归一化和数据增强能提高乳腺的分类准确率,然后发现所设计的三种乳腺癌分类模型中精度最高为BCSCNetⅢ。实验结果表明,BCSCNetⅢ的二分类准确率在99.05%~99.89%,比乳腺癌组织病理学图像分类网络(BHCNet)提升了0.42个百分点;其多分类的准确率在93.06%~95.72%,比BHCNet提升了2.41个百分点。证明了BCSCNet能准确地对乳腺癌组织病理图像进行分类,同时也为计算机辅助乳腺癌诊断提供了可靠的理论支撑。  相似文献   

7.
In this paper, we propose to extend the flexibility of the commonly used 2 × 2 non-overlapping max pooling for Convolutional Neural Network. We name it as Bi-linearly Weighted Fractional Max-Pooling. This proposed method enables max pooling operation below stride size 2, and is computed based on four bi-linearly weighted neighboring input activations. Currently, in a 2 × 2 non-overlapping max pooling operation, as spatial size is halved in both x and y directions, three-quarter of activations in the feature maps are discarded. As such reduction is too abrupt, amount of said pooling operation within a Convolutional Neural Network is very limited: further increasing the number of pooling operation results in too little activation left for subsequent operations. Using our proposed pooling method, spatial size reduction can be more gradual and can be adjusted flexibly. We applied a few combinations of our proposed pooling method into 50-layered ResNet and 19-layered VGGNet with reduced number of filters, and experimented on FGVC-Aircraft, Oxford-IIIT Pet, STL-10 and CIFAR-100 datasets. Even with reduced memory usage, our proposed methods showed reasonable improvement in classification accuracy with 50-layered ResNet. Additionally, with flexibility of our proposed pooling method, we change the reduction rate dynamically every training iteration, and our evaluation results indicated potential regularization effect.  相似文献   

8.
汪鹏  张奥帆  王利琴  董永峰 《计算机应用》2018,38(11):3199-3203
针对图像标注数据集标签分布不平衡问题,提出了基于标签平滑策略的多标签平滑单元(MLSU)。MLSU在网络模型训练过程中自动平滑数据集中的高频标签,使网络适当提升了低频标签的输出值,从而提升了低频标注词的标注性能。为解决图像标注数据集样本数量不足造成网络过拟合的问题,提出了基于迁移学习的卷积神经网络(CNN)模型。首先利用互联网上的大型公共图像数据集对深度网络进行预训练,然后利用目标数据集对网络参数进行微调,构建了一个多标签平滑卷积神经网络模型(CNN-MLSU)。分别在Corel5K和IAPR TC-12图像标注数据集上进行实验,在Corel5K数据集上,CNN-MLSU较卷积神经网络回归方法(CNN-R)的平均准确率与平均召回率分别提升了5个百分点和8个百分点;在IAPR TC-12数据集上,CNN-MLSU较两场K最邻近模型(2PKNN_ML)的平均召回率提升了6个百分点。实验结果表明,基于迁移学习的CNN-MLSU方法能有效地预防网络过拟合,同时提升了低频词的标注效果。  相似文献   

9.
The development of machine learning systems for the diagnosis of rare diseases is challenging, mainly due to the lack of data to study them. This paper surmounts this obstacle and presents the first Computer-Aided Diagnosis (CAD) system for low-prevalence collagen VI-related congenital muscular dystrophies. The proposed CAD system works on images of fibroblast cultures obtained with a confocal microscope and relies on a Convolutional Neural Network (CNN) to classify patches of such images in two classes: samples from healthy persons and samples from persons affected by a collagen VI-related muscular distrophy. This fine-grained classification is then used to generate an overall diagnosis on the query image using a majority voting scheme. The proposed system is advantageous, as it overcomes the lack of training data, points to the possibly problematic areas in the query images, and provides a global quantitative evaluation of the condition of the patients, which is fundamental to monitor the effectiveness of potential therapies. The system achieves a high classification performance, with 95% of accuracy and 92% of precision on randomly selected independent test images, outperforming alternative approaches by a significant margin.  相似文献   

10.
Over the last decade, the ever increasing world-wide demand for early detection of breast cancer at many screening sites and hospitals has resulted in the need of new research avenues. According to the World Health Organization (WHO), an early detection of cancer greatly increases the chances of taking the right decision on a successful treatment plan. The Computer-Aided Diagnosis (CAD) systems are applied widely in the detection and differential diagnosis of many different kinds of abnormalities. Therefore, improving the accuracy of a CAD system has become one of the major research areas. In this paper, a CAD scheme for detection of breast cancer has been developed using deep belief network unsupervised path followed by back propagation supervised path. The construction is back-propagation neural network with Liebenberg Marquardt learning function while weights are initialized from the deep belief network path (DBN-NN). Our technique was tested on the Wisconsin Breast Cancer Dataset (WBCD). The classifier complex gives an accuracy of 99.68% indicating promising results over previously-published studies. The proposed system provides an effective classification model for breast cancer. In addition, we examined the architecture at several train-test partitions.  相似文献   

11.

Diagnosis, detection and classification of tumors, in the brain MRI images, are important because misdiagnosis can lead to death. This paper proposes a method that can diagnose brain tumors in the MRI images and classify them into 5 categories using a Convolutional Neural Network (CNN). The proposed network uses a Convolutional Auto-Encoder Neural Network (CANN) to extract and learn deep features of input images. Extracted deep features from each level are combined to make desirable features and improve results. To classify brain tumor into three categories (Meningioma, Glioma, and Pituitary) the proposed method was applied on Cheng dataset and has reached a considerable performance accuracy of 99.3%. To diagnosis and grading Glioma tumors, the proposed method was applied on IXI and BraTS 2017 datasets, and to classify brain images into six classes including Meningioma, Pituitary, Astrocytoma, High-Grade Glioma, Low-Grade Glioma and Normal images (No tumor), the all datasets including IXI, BraTS2017, Cheng and Hazrat-e-Rassol, was used by the proposed network, and it has reached desirable performance accuracy of 99.1% and 98.5%, respectively.

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12.
最近的研究表明,卷积神经网络的性能可以通过采用跨层连接来提高,典型的残差网络(ResNet)便通过恒等映射方法取得了非常好的图像识别效果.但是通过理论分析,在残差模块中,跨层连接线的布局并没有达到最优设置,造成信息的冗余和层数的浪费,为了进一步提高卷积神经网络的性能,文章设计了两种新型的网络结构,分别命名为C-Fnet...  相似文献   

13.
乳腺癌是女性最常见的恶性肿瘤之一,严重威胁患者健康,因此乳腺钼靶图像多分类对临床诊断乳腺癌具有十分重要的作用。传统卷积神经网络直接采用高级特征对乳腺钼靶图像进行多分类研究,此方法准确率不高。为了进一步提高分类准确率,构建人型网络模型进行分类。此结构通过堆叠的卷积层以及最大池化层来进行图片的低级特征进行提取,通过堆叠的卷积层以及上池化层将特征逐步返回到图片形式的特征图,通过堆叠的卷积层以及最大池化层再次提取到更高级的特征并与之前的低级特征进行级联,将级联的特征经过全局最大池化层进行池化并得到最终分类。在中山大学肿瘤防治中心的1 824幅乳腺钼靶图像做仿真实验,实验结果表明,该方法的准确率达到了74.54%,优于现有相关网络模型。  相似文献   

14.
In agricultural engineering, the main challenge is on methodologies used for disease detection. The manual methods depend on the experience of the personal. Due to large variation in environmental condition, disease diagnosis and classification becomes a challenging task. Apart from the disease, the leaves are affected by climate changes which is hard for the image processing method to discriminate the disease from the other background. In Cucurbita gourd family, the disease severity examination of leaf samples through computer vision, and deep learning methodologies have gained popularity in recent years. In this paper, a hybrid method based on Convolutional Neural Network (CNN) is proposed for automatic pumpkin leaf image classification. The Proposed Denoising and deep Convolutional Neural Network (CNN) method enhances the Pumpkin Leaf Pre-processing and diagnosis. Real time data base was used for training and testing of the proposed work. Investigation on existing pre-trained network Alexnet and googlenet was investigated is done to evaluate the performance of the proposed method. The system and computer simulations were performed using Matlab tool.  相似文献   

15.

The 2019 novel coronavirus disease (COVID-19), with a starting point in China, has spread rapidly among people living in other countries and is approaching approximately 101,917,147 cases worldwide according to the statistics of World Health Organization. There are a limited number of COVID-19 test kits available in hospitals due to the increasing cases daily. Therefore, it is necessary to implement an automatic detection system as a quick alternative diagnosis option to prevent COVID-19 spreading among people. In this study, five pre-trained convolutional neural network-based models (ResNet50, ResNet101, ResNet152, InceptionV3 and Inception-ResNetV2) have been proposed for the detection of coronavirus pneumonia-infected patient using chest X-ray radiographs. We have implemented three different binary classifications with four classes (COVID-19, normal (healthy), viral pneumonia and bacterial pneumonia) by using five-fold cross-validation. Considering the performance results obtained, it has been seen that the pre-trained ResNet50 model provides the highest classification performance (96.1% accuracy for Dataset-1, 99.5% accuracy for Dataset-2 and 99.7% accuracy for Dataset-3) among other four used models.

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16.
针对传统基于注意力机制的神经网络不能联合关注局部特征和旋转不变特征的问题,提出一种基于多分支神经网络模型的弱监督细粒度图像分类方法。首先,用轻量级类激活图(CAM)网络定位有潜在语义信息的局部区域,设计可变形卷积的残差网络ResNet-50和旋转不变编码的方向响应网络(ORN);其次,利用预训练模型分别初始化特征网络,并输入原图和以上局部区域分别对模型进行微调;最后,组合三个分支内损失和分支间损失优化整个网络,对测试集进行分类预测。所提方法在CUB-200-2011和FGVC_Aircraft数据集上的分类准确率分别达到87.7%和90.8%,与多注意力卷积神经网络(MA-CNN)方法相比,分别提高了1.2个百分点和0.9个百分点;在Aircraft_2数据集上的分类准确率达到91.8%,比ResNet-50网络提高了4.1个百分点。实验结果表明,所提方法有效提高了弱监督细粒度图像分类的准确率。  相似文献   

17.
岩心聚焦离子束扫描电镜(FIB-SEM)图像存在灰度分布不均及孔隙内局部高亮等现象,采用传统图像分割算法所得孔隙分割精度较低,而基于轮廓的分割算法需对孔隙进行人工标记,操作繁琐且无法精确提取孔隙。提出一种利用卷积神经网络的端到端岩心FIB-SEM图像分割算法。结合光流法与分水岭分割图像标注法构建岩心FIB-SEM数据集,联合ResNet50残差网络、通道和空间注意力机制提取特征信息,采用改进的特征金字塔注意力模块提取多尺度特征,利用亚像素卷积模块经上采样获取更精细的孔隙边缘并恢复为原始分辨率。实验结果表明,与阈值分割算法和基于主动轮廓的岩心FIB-SEM分割算法相比,该算法分割精度更高且无需人工操作,其平均像素精度和平均交并比分别达到90.00%和85.81%。  相似文献   

18.
邱津怡  罗俊  李秀  贾伟  倪福川  冯慧 《计算机应用》2019,39(10):2930-2936
葡萄品种质量检测需要识别多类别的葡萄,而葡萄图片中存在多种景深变化、多串等多种场景,单一预处理方法存在局限导致葡萄识别的效果不佳。实验的研究对象是大棚中采集的15个类别的自然场景葡萄图像,并建立相应图像数据集Vitis-15。针对葡萄图像中同一类别的差异较大而不同类别的差异较小的问题,提出一种基于卷积神经网络(CNN)的多尺度葡萄图像识别方法。首先,对Vitis-15数据集中的数据通过三种方法进行预处理:旋转图像的数据扩增方法、中心裁剪的多尺度图像方法以及前两种方法的数据融合方法;然后,采用迁移学习方法和卷积神经网络方法来进行分类识别,迁移学习选取ImageNet上预训练的Inception V3网络模型,卷积神经网络采用AlexNet、ResNet、Inception V3这三类模型;最后,提出适合Vitis-15的多尺度图像数据融合的分类模型MS-EAlexNet。实验结果表明,在同样的学习率和同样的测试集上,数据融合方法在MS-EAlexNet上的测试准确率达到了99.92%,相较扩增和多尺度图像方法提升了近1个百分点,并且所提方法在分类小样本数据集上具有较高的效率。  相似文献   

19.
贺煜航  刘棪  陈刚 《计算机工程》2022,48(12):261-269
心电图分析是一种被广泛应用的心脏疾病诊断方法。传统的心电图分析严重依赖医生个人水平,容易出现误诊、漏诊现象,效率较低,且不能有效利用高频信号提供的有价值信息。基于卷积神经网络(CNN)的心电图自动分类方法在一定程度上提高了诊断效率,但依然存在对高频信息利用不充分的问题,且单一的卷积神经网络由于受感受野的限制和权重共享的影响,导致无法充分利用全局信息,分类准确率有待提高。提出一种基于注意力机制与图卷积网络的心电图多标签分类模型MLECG-AGCN,通过设计基于注意力机制的CNN网络,提高网络对高频信号的利用率。引入图卷积网络,以有效利用全局信息和特征空间邻域样本信息,从而协助样本进行分类,提高分类结果的准确率。基于注意力机制的CNN网络通过高通滤波器突出原始信号的高频位置,生成注意力图,并将注意力图嵌入到原始信号中,增强网络关注高频信号的能力。在PTB-XL数据集上的实验结果表明,基于注意力机制的CNN网络与自适应图卷积网络的结合有效提高了心电图分类精度,与Multi-ECGNet、ResNet18、ResNet101等模型相比,MLECG-AGCN模型取得了较高的AUROC值,为0.943 639。  相似文献   

20.
针对城市环境卫生提出的对市民生活垃圾进行分类回收的要求,考虑计算机卷积神经网络在图片分类中的强大表现,提出了基于深度学习中卷积神经网络对垃圾图片处理以及输出识别的新模型与方法。针对目前图像局部特征表达存在的复杂性,模糊性等不足,采用特征多层池化以及系统神经网络学习的方式进行优化。同时在ResNet101模型的基础上设计并构建了基于CNN(Convolutional Neural Network)算法的新模型框架,此系统模型也能实现端与端的实时识别。新模型提高了对训练样本图像信息提取的精确度以及图片识别的准确率,实验表明识别准确率平均提高了10%。为未来实现人工智能垃圾分类提供图像识别模型基础。  相似文献   

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