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91.
Walid El-Shafai Noha A. El-Hag Ahmed Sedik Ghada Elbanby Fathi E. Abd El-Samie Naglaa F. Soliman Hussah Nasser AlEisa Mohammed E. Abdel Samea 《计算机、材料和连续体(英文)》2023,74(2):2905-2919
Medical image fusion is considered the best method for obtaining one image with rich details for efficient medical diagnosis and therapy. Deep learning provides a high performance for several medical image analysis applications. This paper proposes a deep learning model for the medical image fusion process. This model depends on Convolutional Neural Network (CNN). The basic idea of the proposed model is to extract features from both CT and MR images. Then, an additional process is executed on the extracted features. After that, the fused feature map is reconstructed to obtain the resulting fused image. Finally, the quality of the resulting fused image is enhanced by various enhancement techniques such as Histogram Matching (HM), Histogram Equalization (HE), fuzzy technique, fuzzy type Π, and Contrast Limited Histogram Equalization (CLAHE). The performance of the proposed fusion-based CNN model is measured by various metrics of the fusion and enhancement quality. Different realistic datasets of different modalities and diseases are tested and implemented. Also, real datasets are tested in the simulation analysis. 相似文献
92.
Oznur Ozaltin Orhan Coskun Ozgur Yeniay Abdulhamit Subasi 《International journal of imaging systems and technology》2023,33(1):69-91
Classification of brain hemorrhage computed tomography (CT) images provides a better diagnostic implementation for emergency patients. Attentively, each brain CT image must be examined by doctors. This situation is time-consuming, exhausting, and sometimes leads to making errors. Hence, we aim to find the best algorithm owing to a requirement for automatic classification of CT images to detect brain hemorrhage. In this study, we developed OzNet hybrid algorithm, which is a novel convolution neural networks (CNN) algorithm. Although OzNet achieves high classification performance, we combine it with Neighborhood Component Analysis (NCA) and many classifiers: Artificial neural networks (ANN), Adaboost, Bagging, Decision Tree, K-Nearest Neighbor (K-NN), Linear Discriminant Analysis (LDA), Naïve Bayes and Support Vector Machines (SVM). In addition, Oznet is utilized for feature extraction, where 4096 features are extracted from the fully connected layer. These features are reduced to have significant and informative features with minimum loss by NCA. Eventually, we use these classifiers to classify these significant features. Finally, experimental results display that OzNet-NCA-ANN excellent classifier model and achieves 100% accuracy with created Dataset 2 from Brain Hemorrhage CT images. 相似文献
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近年来,深度学习中的卷积神经网络已经广泛运用于图像识别领域,它不仅显著提升了识别准确率,同时在特征提取速度方面也优于许多传统方法。本文针对高速公路环境下的车型识别问题,引入卷积神经网络(CNNs)理论,设计相应特征提取算法,并结合SVM分类器构建识别系统。通过对高速公路上主要三种车型(小车、客车、货车)的分类实验显示,本文方法在识别精度及速度上均取得较显著的提高。 相似文献
95.
一种基于CLMF的深度卷积神经网络模型 总被引:2,自引:0,他引:2
针对传统人工特征提取模型难以满足复杂场景下目标识别的需求, 提出了一种基于CLMF的深度卷积神经网络(Convolutional neural networks with candidate location and multi-feature fusion, CLMF-CNN).该模型结合视觉显著性、多特征融合和CNN模型实现目标对象的识别. 首先, 利用加权Itti模型获取目标候选区; 然后, 利用CNN模型从颜色、亮度多特征角度提取目标对象的特征, 经过加权融合供目标识别; 最后, 与单一特征以及目前的流行算法进行对比实验, 结果表明本文模型不仅在同等条件下正确识别率得到了提高, 同时, 达到实时性要求. 相似文献
96.
基于CNN的监控视频事件检测 总被引:2,自引:1,他引:1
复杂监控视频中事件检测是一个具有挑战性的难题, 而TRECVID-SED评测使用的数据集取自机场的实际监控视频,以高难度著称. 针对TRECVID-SED评测集, 提出了一种基于卷积神经网络(Convolutional neural network, CNN)级联网络和轨迹分析的监控视频事件检测综合方案. 在该方案中, 引入级联CNN网络在拥挤场景中准确地检测行人, 为跟踪行人奠定了基础; 采用CNN网络检测具有关键姿态的个体事件, 引入轨迹分析方法检测群体事件. 该方案在国际评测中取得了很好的评测排名: 在6个事件检测的评测中, 3个事件检测排名第一. 相似文献
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目的 为进一步提高遥感影像的分类精度,将卷积神经网络(CNN)与条件随机场(CRF)两个模型结合,提出一种新的分类方法。方法 首先采用CNN对遥感图像进行预分类,并将其类成员概率定义为CRF模型的一阶势函数;然后利用高斯核函数的线性组合定义CRF模型的二阶势函数,用全连接的邻域结构代替常见的4邻域或8邻域;接着加入区域约束,使用Mean-shift分割方法得到超像素,通过计算超像素的后验概率均值修正各像素的分类结果,鼓励连通区域结果的一致性;最后采用平均场近似算法实现整个模型的推断。结果 选用3组高分辨率遥感图像进行地物分类实验。本文方法不仅能抑制更多的分类噪声,同时还可以改善过平滑现象,保护各类地物的边缘信息。实验采用类精度、总体分类精度OA、平均分类精度AA,以及Kappa系数4个指标进行定量分析,与支持向量机(SVM)、CNN和全连接CRF相比,最终获得的各项精度均得到显著提升,其中,AA提高3.28个百分点,OA提高3.22个百分点,Kappa提高5.07个百分点。结论 将CNN与CRF两种模型融合,不仅可以获得像元本质化的特征,而且同时还考虑了图像的空间上下文信息,使分类更加准确,后加入的约束条件还能进一步保留地物目标的局部信息。本文方法适用于遥感图像分类领域,是一种精确有效的分类方法。 相似文献
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100.
H. Giebl A. Berner G. Reischl H. Puxbaum A. Kasper-Giebl R. Hitzenberger 《Journal of aerosol science》2002,33(12):1623-1634
The cloud droplet activation of monodisperse laboratory aerosols consisting of single organic and inorganic substances as well as a mixture of several substances was investigated using the University of Vienna cloud condensation nuclei counter (CCNC). The CCNC operates on the principle of a static thermal diffusion chamber. Water vapour supersaturations can be set in the range from 0.1% to 2%. Aqueous solutions of oxalic acid and malonic acid as well as solutions of inorganic compounds (NaCl and (NH4)2SO4) were nebulized in a Collison atomizer and then passed through a closed-loop differential mobility particle spectrometer to produce monodispersed particles. An internally mixed aerosol consisting of ammonium sulphate, oxalic acid and malonic acid with relative concentrations resembling those found in cloud water at a mountain station [Löflund, Kasper-Giebl, Schuster, Giebl, Hitzenberger, Reischl et al. (2002) Atmos. Environ. 36, 1553] was also investigated for cloud condensation nuclei (CCN) activation. All these particles were activated at supersaturations expected from Köhler theory. Oxalic and malonic acid particles are therefore expected to be good atmospheric CCN both as pure particles and as internally mixed particles containing other chemical compounds. 相似文献