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基于手机拍照结合Image J软件对干辣椒外观品质的分级研究 被引量:1
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作者 胡晋伟 赵志峰 +4 位作者 张欣莹 祝贺 李波 孙海清 徐炜桢 《食品与发酵工业》 CAS 北大核心 2025年第1期273-279,共7页
干辣椒外观形状和色泽是其品质分类的重要指标。目前GB 10465—1989《辣椒干》中对干辣椒外观形状和色泽的检测方式还停留在人工检测阶段,通常受到主观感知、误差、视觉生理等多种因素影响,未形成科学标准化的检测方法。该研究利用手机... 干辣椒外观形状和色泽是其品质分类的重要指标。目前GB 10465—1989《辣椒干》中对干辣椒外观形状和色泽的检测方式还停留在人工检测阶段,通常受到主观感知、误差、视觉生理等多种因素影响,未形成科学标准化的检测方法。该研究利用手机拍照对干辣椒获取图像,通过Image J软件进行图像处理,提出了一种便捷、快速、准确的干辣椒外观形状相关特征量的测定方法。与游标卡尺法、剪纸法等人工测量相比,该方法更方便快速,可用于干辣椒的长度、宽度、面积等表型指标的测量。同时,通过构建红绿蓝(RGB)色彩模型获得干辣椒的外观颜色特征参数,色泽分选采用R/(G+B)比率为分级依据,结合干辣椒宽长比和面积可以将干辣椒分为优质、合格、不合格3个等级。 展开更多
关键词 干辣椒 手机拍照 image J软件 RGB色彩模型 分级
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Infrared aircraft few-shot classification method based on cross-correlation network
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作者 HUANG Zhen ZHANG Yong GONG Jin-Fu 《红外与毫米波学报》 北大核心 2025年第1期103-111,共9页
In response to the scarcity of infrared aircraft samples and the tendency of traditional deep learning to overfit,a few-shot infrared aircraft classification method based on cross-correlation networks is proposed.This... In response to the scarcity of infrared aircraft samples and the tendency of traditional deep learning to overfit,a few-shot infrared aircraft classification method based on cross-correlation networks is proposed.This method combines two core modules:a simple parameter-free self-attention and cross-attention.By analyzing the self-correlation and cross-correlation between support images and query images,it achieves effective classification of infrared aircraft under few-shot conditions.The proposed cross-correlation network integrates these two modules and is trained in an end-to-end manner.The simple parameter-free self-attention is responsible for extracting the internal structure of the image while the cross-attention can calculate the cross-correlation between images further extracting and fusing the features between images.Compared with existing few-shot infrared target classification models,this model focuses on the geometric structure and thermal texture information of infrared images by modeling the semantic relevance between the features of the support set and query set,thus better attending to the target objects.Experimental results show that this method outperforms existing infrared aircraft classification methods in various classification tasks,with the highest classification accuracy improvement exceeding 3%.In addition,ablation experiments and comparative experiments also prove the effectiveness of the method. 展开更多
关键词 infrared imaging aircraft classification few-shot learning parameter-free attention cross attention
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Effective distributed convolutional neural network architecture for remote sensing images target classification with a pre-training approach 被引量:3
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作者 LI Binquan HU Xiaohui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第2期238-244,共7页
How to recognize targets with similar appearances from remote sensing images(RSIs) effectively and efficiently has become a big challenge. Recently, convolutional neural network(CNN) is preferred in the target classif... How to recognize targets with similar appearances from remote sensing images(RSIs) effectively and efficiently has become a big challenge. Recently, convolutional neural network(CNN) is preferred in the target classification due to the powerful feature representation ability and better performance. However,the training and testing of CNN mainly rely on single machine.Single machine has its natural limitation and bottleneck in processing RSIs due to limited hardware resources and huge time consuming. Besides, overfitting is a challenge for the CNN model due to the unbalance between RSIs data and the model structure.When a model is complex or the training data is relatively small,overfitting occurs and leads to a poor predictive performance. To address these problems, a distributed CNN architecture for RSIs target classification is proposed, which dramatically increases the training speed of CNN and system scalability. It improves the storage ability and processing efficiency of RSIs. Furthermore,Bayesian regularization approach is utilized in order to initialize the weights of the CNN extractor, which increases the robustness and flexibility of the CNN model. It helps prevent the overfitting and avoid the local optima caused by limited RSI training images or the inappropriate CNN structure. In addition, considering the efficiency of the Na¨?ve Bayes classifier, a distributed Na¨?ve Bayes classifier is designed to reduce the training cost. Compared with other algorithms, the proposed system and method perform the best and increase the recognition accuracy. The results show that the distributed system framework and the proposed algorithms are suitable for RSIs target classification tasks. 展开更多
关键词 convolutional NEURAL network (CNN) DISTRIBUTED architecture REMOTE SENSING images (RSIs) TARGET classification pre-training
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Deep hybrid: Multi-graph neural network collaboration for hyperspectral image classification 被引量:4
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作者 Ding Yao Zhang Zhi-li +4 位作者 Zhao Xiao-feng Cai Wei He Fang Cai Yao-ming Wei-Wei Cai 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第5期164-176,共13页
With limited number of labeled samples,hyperspectral image(HSI)classification is a difficult Problem in current research.The graph neural network(GNN)has emerged as an approach to semi-supervised classification,and th... With limited number of labeled samples,hyperspectral image(HSI)classification is a difficult Problem in current research.The graph neural network(GNN)has emerged as an approach to semi-supervised classification,and the application of GNN to hyperspectral images has attracted much attention.However,in the existing GNN-based methods a single graph neural network or graph filter is mainly used to extract HSI features,which does not take full advantage of various graph neural networks(graph filters).Moreover,the traditional GNNs have the problem of oversmoothing.To alleviate these shortcomings,we introduce a deep hybrid multi-graph neural network(DHMG),where two different graph filters,i.e.,the spectral filter and the autoregressive moving average(ARMA)filter,are utilized in two branches.The former can well extract the spectral features of the nodes,and the latter has a good suppression effect on graph noise.The network realizes information interaction between the two branches and takes good advantage of different graph filters.In addition,to address the problem of oversmoothing,a dense network is proposed,where the local graph features are preserved.The dense structure satisfies the needs of different classification targets presenting different features.Finally,we introduce a GraphSAGEbased network to refine the graph features produced by the deep hybrid network.Extensive experiments on three public HSI datasets strongly demonstrate that the DHMG dramatically outperforms the state-ofthe-art models. 展开更多
关键词 Graph neural network Hyperspectral image classification Deep hybrid network
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SAR images classification method based on Dempster-Shafer theory and kernel estimate
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作者 He Chu Xia Guisong Sun Hong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期210-216,共7页
To study the scene classification in the Synthetic Aperture Radar (SAR) image, a novel method based on kernel estimate, with the Maxkov context and Dempster-Shafer evidence theory is proposed. Initially, a nonpaxame... To study the scene classification in the Synthetic Aperture Radar (SAR) image, a novel method based on kernel estimate, with the Maxkov context and Dempster-Shafer evidence theory is proposed. Initially, a nonpaxametric Probability Density Function (PDF) estimate method is introduced, to describe the scene of SAR images. And then under the Maxkov context, both the determinate PDF and the kernel estimate method axe adopted respectively, to form a primary classification. Next, the primary classification results are fused using the evidence theory in an unsupervised way to get the scene classification. Finally, a regularization step is used, in which an iterated maximum selecting approach is introduced to control the fragments and modify the errors of the classification. Use of the kernel estimate and evidence theory can describe the complicated scenes with little prior knowledge and eliminate the ambiguities of the primary classification results. Experimental results on real SAR images illustrate a rather impressive performance. 展开更多
关键词 image classification Synthetic aperture Radar (SAR) Dempster-Shafer theory Kernel estimate.
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Video learning based image classification method for object recognition
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作者 LEE Hong-ro SHIN Yong-ju 《Journal of Central South University》 SCIE EI CAS 2013年第9期2399-2406,共8页
Automatic image classification is the first step toward semantic understanding of an object in the computer vision area.The key challenge of problem for accurate object recognition is the ability to extract the robust... Automatic image classification is the first step toward semantic understanding of an object in the computer vision area.The key challenge of problem for accurate object recognition is the ability to extract the robust features from various viewpoint images and rapidly calculate similarity between features in the image database or video stream.In order to solve these problems,an effective and rapid image classification method was presented for the object recognition based on the video learning technique.The optical-flow and RANSAC algorithm were used to acquire scene images from each video sequence.After the selection of scene images,the local maximum points on comer of object around local area were found using the Harris comer detection algorithm and the several attributes from local block around each feature point were calculated by using scale invariant feature transform (SIFT) for extracting local descriptor.Finally,the extracted local descriptor was learned to the three-dimensional pyramid match kernel.Experimental results show that our method can extract features in various multi-viewpoint images from query video and calculate a similarity between a query image and images in the database. 展开更多
关键词 image classification multi-viewpoint image feature extraction video learning
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Indexing of Content-Based Image Retrieval System with Image Understanding Approach
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作者 李学龙 刘政凯 俞能海 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第2期63-68,共6页
This paper presents a novel efficient semantic image classification algorithm for high-level feature indexing of high-dimension image database. Experiments show that the algorithm performs well. The size of the train ... This paper presents a novel efficient semantic image classification algorithm for high-level feature indexing of high-dimension image database. Experiments show that the algorithm performs well. The size of the train set and the test set is 7 537 and 5 000 respectively. Based on this theory, another ground is built with 12,000 images, which are divided into three classes: city, landscape and person, the total result of the classifications is 88.92%, meanwhile, some preliminary results are presented for image understanding based on semantic image classification and low level features. The groundtruth for the experiments is built with the images from Corel database, photos and some famous face databases. 展开更多
关键词 Content-based image retrieval image classification image indexing.
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A New Wavelet-Based Document Image Segmentation Scheme
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作者 赵健 李道京 +1 位作者 俞卞章 耿军平 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2002年第3期86-90,共5页
The document image segmentation is very useful for printing, faxing and data processing. An algorithm is developed for segmenting and classifying document image. Feature used for classification is based on the histogr... The document image segmentation is very useful for printing, faxing and data processing. An algorithm is developed for segmenting and classifying document image. Feature used for classification is based on the histogram distribution pattern of different image classes. The important attribute of the algorithm is using wavelet correlation image to enhance raw image's pattern, so the classification accuracy is improved. In this paper document image is divided into four types; background, photo, text and graph. Firstly, the document image background has been distingusished easily by former normally method;secondly, three image types will be distinguished by their typical histograms, in order to make histograms feature clearer, each resolution's HH wavelet subimage is used to add to the raw image at their resolution. At last, the photo, text and praph have been devided according to how the feature fit to the Laplacian distrbution by 2 and L . Simulations show that classification accuracy is significantly improved. The comparison with related shows that our algorithm provides both lower classification error rates and better visual results. 展开更多
关键词 Document image SEGMENTATION classification Wavelet Histogram.
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Modulation classification based on spectrogram
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作者 杨杰 叶晨洲 周越 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第3期475-488,共14页
The aim of modulation classification (MC) is to identify the modulation type of a commtmication signal. It plays an important role in many cooperative or noncooperative communication applications. Three spectrogram-... The aim of modulation classification (MC) is to identify the modulation type of a commtmication signal. It plays an important role in many cooperative or noncooperative communication applications. Three spectrogram-based modulation classification methods are proposed. Their recognition scope and performance are investigated or evaluated by theoretical analysis and extensive simulation studies. The method taking moment-like features is robust to frequency offset while the other two, which make use of principal component analysis (PCA) with different transformation inputs, can achieve satisfactory accuracy even at low SNR (as low as 2 dB). Due to the properties of spectrogram, the statistical pattern recognition techniques, and the image preprocessing steps, all of our methods are insensitive to unknown phase and frequency offsets, timing errors, and the arriving sequence of symbols. 展开更多
关键词 modulation classification spectrcgram image processing principal component analysis support vector machine.
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基于改进Res2Net与迁移学习的水果图像分类 被引量:3
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作者 吴迪 肖衍 +2 位作者 沈学军 万琴 陈子涵 《电子科技大学学报》 北大核心 2025年第1期62-71,共10页
针对传统水果图像分类算法特征学习能力弱和细粒度特征信息表示不强的缺点,提出一种基于改进Res2Net与迁移学习的水果图像分类算法。首先,针对网络结构,在Res2Net的残差单元中引入动态多尺度融合注意力模块,对各种尺寸的图像动态地生成... 针对传统水果图像分类算法特征学习能力弱和细粒度特征信息表示不强的缺点,提出一种基于改进Res2Net与迁移学习的水果图像分类算法。首先,针对网络结构,在Res2Net的残差单元中引入动态多尺度融合注意力模块,对各种尺寸的图像动态地生成卷积核,利用meta-ACON激活函数优化ReLU激活函数,动态学习激活函数的线性和非线性,自适应选择是否激活神经元;其次,采用基于模型迁移的训练方式进一步提升分类的效率与鲁棒性。实验结果表明,该算法在Fruit-Dataset和Fruits-360数据集上的测试准确率相比Res2Net提升了1.2%和1.0%,召回率相比Res2Net提升了1.13%和0.89%,有效提升了水果图像分类性能。 展开更多
关键词 图像分类 Res2Net 动态多尺度融合注意力 激活函数 迁移学习
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计算机视觉领域对抗样本检测综述 被引量:1
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作者 张鑫 张晗 +1 位作者 牛曼宇 姬莉霞 《计算机科学》 北大核心 2025年第1期345-361,共17页
随着数据量的增加和硬件性能的提升,深度学习在计算机视觉领域取得了显著进展.然而,深度学习模型容易受到对抗样本的攻击,导致输出发生显著变化.对抗样本检测作为一种有效的防御手段,可以在不改变模型结构的前提下防止对抗样本对深度学... 随着数据量的增加和硬件性能的提升,深度学习在计算机视觉领域取得了显著进展.然而,深度学习模型容易受到对抗样本的攻击,导致输出发生显著变化.对抗样本检测作为一种有效的防御手段,可以在不改变模型结构的前提下防止对抗样本对深度学习模型造成影响.首先,对近年来的对抗样本检测研究工作进行了整理,分析了对抗样本检测与训练数据的关系,根据检测方法所使用特征进行分类,系统全面地介绍了计算机视觉领域的对抗样本检测方法;然后,对一些结合跨领域技术的检测方法进行了详细介绍,统计了训练和评估检测方法的实验配置;最后,汇总了一些有望应用于对抗样本检测的技术,并对未来的研究挑战进行展望. 展开更多
关键词 深度学习 对抗样本攻击 对抗样本检测 人工智能安全 图像分类
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基于全局相关语义重要性的语义压缩算法 被引量:1
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作者 李勇 刘志强 +1 位作者 田茂幸 贾松霖 《浙江大学学报(工学版)》 北大核心 2025年第4期795-803,共9页
为了改善传统压缩方法在保留深层语义信息方面的不足,提出新型语义压缩算法.将全局相关语义重要性(GCSI)作为语义重要性度量参数,综合考虑语义任务相关性和语义内在相关性指标,全面评估语义特征的重要性,实现有效的语义压缩.实验结果表... 为了改善传统压缩方法在保留深层语义信息方面的不足,提出新型语义压缩算法.将全局相关语义重要性(GCSI)作为语义重要性度量参数,综合考虑语义任务相关性和语义内在相关性指标,全面评估语义特征的重要性,实现有效的语义压缩.实验结果表明,在不同信道条件下,相比传统方法,所提算法的压缩性能提升超过30%;在低带宽和低信噪比环境中,所提算法的分类准确度提升超过10%.在相同带宽和性能要求下,相较于现有基于语义任务相关性的语义压缩方法,所提算法的噪声稳定性更好,显著降低了网络传输压力,提升了任务处理性能,有能力面对未来逐步增加的数据传输需求挑战. 展开更多
关键词 语义通信 图片分类 语义重要性 语义压缩 语义相似度
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基于深度神经网络的遗传算法对抗攻击 被引量:1
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作者 范海菊 马锦程 李名 《河南师范大学学报(自然科学版)》 北大核心 2025年第2期82-90,I0007,共10页
深度神经网络(deep neural network,DNN)能够取得良好的分类识别效果,但在训练图像中添加微小扰动进行对抗攻击,其识别准确率会大大下降.在提出的方法中,通过遗传算法得到最优扰动后,修改图像极少的像素生成对抗样本,实现对VGG16等3个... 深度神经网络(deep neural network,DNN)能够取得良好的分类识别效果,但在训练图像中添加微小扰动进行对抗攻击,其识别准确率会大大下降.在提出的方法中,通过遗传算法得到最优扰动后,修改图像极少的像素生成对抗样本,实现对VGG16等3个基于卷积神经网络图像分类器的成功攻击.实验结果表明在对3个分类模型进行单像素攻击时,67.92%的CIFAR-10数据集中的自然图像可以被扰动到至少一个目标类,平均置信度为79.57%,攻击效果会随着修改像素的增加进一步提升.此外,相比于LSA和FGSM方法,攻击效果有着显著提升. 展开更多
关键词 卷积神经网络 遗传算法 对抗攻击 图像分类 信息安全
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基于轻量化网络和迁移学习的岩石智能识别 被引量:1
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作者 李顺勇 李青辉 邢煜曼 《科学技术与工程》 北大核心 2025年第5期1774-1782,共9页
在岩石图像识别中,实现岩石快速准确的识别是岩石数字化发展的关键。其中,光照、湿度等环境因素引起的图像模糊问题成为岩石智能识别的最大挑战之一。基于此,提出了一种新的深度学习方法(MbileNetV3-small-RegNetX)来识别岩石图像,其适... 在岩石图像识别中,实现岩石快速准确的识别是岩石数字化发展的关键。其中,光照、湿度等环境因素引起的图像模糊问题成为岩石智能识别的最大挑战之一。基于此,提出了一种新的深度学习方法(MbileNetV3-small-RegNetX)来识别岩石图像,其适用于移动设备等资源有限的场景。在RegNet网络的基础上采用迁移学习方法,结合MobileNetV3残差结构与通道注意力(squeeze-and-excitation,SE)模块的优势,有效地优化了特征提取与网络结构,并显著提升了检测速度。为验证该方法的准确性,将新模型与当下主流的轻量化模型(DenseNet和ShuffleNet)进行消融对比实验。结果显示,所提模型表现出高精度(82.15%)、快速(0.06 GFLOPs)的特点。此外,该模型对于光照、湿度等环境因素引起的图像模糊具有良好的适应性。 展开更多
关键词 岩石识别 深度学习 图像分类 迁移学习 MobileNet网络
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基于多模态的缺陷绝缘子图像的多标签分类 被引量:1
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作者 周景 王满意 田兆星 《高电压技术》 北大核心 2025年第2期642-651,共10页
对巡检图像中绝缘子缺陷准确分类是输电线路自动巡检领域中的关键技术之一。针对传统深度学习的分类方法对文本信息利用不够充分以及绝缘子图像分类标签较为单一的问题,该文首次提出了一种基于多模态的缺陷绝缘子图像的多标签分类方法... 对巡检图像中绝缘子缺陷准确分类是输电线路自动巡检领域中的关键技术之一。针对传统深度学习的分类方法对文本信息利用不够充分以及绝缘子图像分类标签较为单一的问题,该文首次提出了一种基于多模态的缺陷绝缘子图像的多标签分类方法。首先,采用一种多模态联合数据增强方法,实现了绝缘子图像和标签文本间跨模态的数据增强。然后,使用Vision Transformer网络提取图像的特征信息和BERT网络提取标签文本的特征信息,充分利用图像和标签文本的特征信息,从不同模态获取全面的信息,提高了网络的分类能力。最后,通过对比学习的方式将图像和文本的特征信息关联,增强网络分类的可靠性的同时,又为分类结果提供了良好的可解释性。实验结果表明,该方法的分类总体准确率达到93.87%,在同一数据集中对比其他模型,分类性能具有明显优势,为多模态技术在电网领域的应用提供了较好的基础。 展开更多
关键词 绝缘子图像 多标签分类 多模态 对比学习 数据增强
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任意维度重建磁共振对骶管囊肿进行精准分型对于指导微创手术和康复的意义
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作者 孙建军 马千权 +11 位作者 尹晓亮 杨辰龙 张嘉 陈素华 吴超 谢京城 韩芸峰 林国中 司雨 杨军 邬海博 赵强 《北京大学学报(医学版)》 北大核心 2025年第2期303-308,共6页
目的:运用任意维度重建磁共振对骶管囊肿进行精准分型,有效指导患者的微创手术和术后个性化康复。方法:2021年3—12月,应用任意维度重建磁共振评估骶管囊肿患者的围手术期状况,根据神经根或漏口轨迹重建出囊肿内神经根走行和囊肿漏口情... 目的:运用任意维度重建磁共振对骶管囊肿进行精准分型,有效指导患者的微创手术和术后个性化康复。方法:2021年3—12月,应用任意维度重建磁共振评估骶管囊肿患者的围手术期状况,根据神经根或漏口轨迹重建出囊肿内神经根走行和囊肿漏口情况,对骶管囊肿进行精准分型并精准设计手术切口和骶管后壁骨窗范围。于显微镜下验证术前分型的准确性,指导对应术式治疗不同类型的骶管囊肿。术后复查神经根水肿情况、术腔是否有积液等,制定患者个性化的康复方案,便于患者顺利康复。结果:92例骶管囊肿患者中,58例(63.0%)为内含神经根囊肿,29例(31.5%)为内无神经根囊肿,5例(5.4%)为混合型骶管囊肿。58例内含神经根囊肿的患者中,手术显微镜下复核影像临床分型的准确度可达96.6%(56/58),只有2例较大的单发囊肿、神经根在囊肿上极闪现被误认为内无神经根型。29例内无神经根的骶管囊肿患者中,显微镜下复核影像的准确度达100%。对12例复发骶管囊肿内部的神经根和漏口情况的判断准确度达到100%。术后1个月发现迟发性术腔积液2例,予以艾灸、泡澡等康复治疗,患者术后4~6个月积液消失。结论:任意维度重建磁共振在术前可准确判断骶管囊肿的临床分型,指导手术精准执行,并个性化改善患者的康复效果。 展开更多
关键词 骶管囊肿 临床分型 脊神经根 磁共振成像 图像重建
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基于改进YOLOv8s的杭白菊检测与花期分类
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作者 施国英 纪嘉鹏 +3 位作者 李天华 李文显 李扬 张观山 《农业工程学报》 北大核心 2025年第7期192-199,共8页
为精准识别与分类不同花期杭白菊,满足自动化采摘要求,该研究提出一种基于改进YOLOv8s的杭白菊检测模型-YOLOv8s-RDL。首先,该研究将颈部网络(neck)的C2f(faster implementation of CSP bottleneck with 2 convolutions)模块替换为RCS-O... 为精准识别与分类不同花期杭白菊,满足自动化采摘要求,该研究提出一种基于改进YOLOv8s的杭白菊检测模型-YOLOv8s-RDL。首先,该研究将颈部网络(neck)的C2f(faster implementation of CSP bottleneck with 2 convolutions)模块替换为RCS-OSA(one-shot aggregation of reparameterized convolution based on channel shuffle)模块,以提升骨干网络(backbone)特征融合效率;其次,将检测头更换为DyHead(dynamic head),并融合DCNv3(deformable convolutional networks v3),借助多头自注意力机制增强目标检测头的表达能力;最后,采用LAMP(layer-adaptive magnitude-based pruning)通道剪枝算法减少参数量,降低模型复杂度。试验结果表明,YOLOv8s-RDL模型在菊米和胎菊的花期分类中平均精度分别达到96.3%和97.7%,相较于YOLOv8s模型,分别提升了3.8和1.5个百分点,同时权重文件大小较YOLOv8s减小了6 MB。该研究引入TIDE(toolkit for identifying detection and segmentation errors)评估指标,结果显示,YOLOv8s-RDL模型分类错误和背景检测错误相较YOLOv8s模型分别降低0.55和1.26。该研究为杭白菊分花期自动化采摘提供了理论依据和技术支撑。 展开更多
关键词 图像识别 YOLOv8s 杭白菊检测 花期分类 LAMP
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基于图元变换的建筑彩绘纹样图像矢量化方法
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作者 曹力 张腾腾 +2 位作者 颜子麦 龚辰晨 赵洋 《计算机应用研究》 北大核心 2025年第7期2206-2212,共7页
为了对包含可复用图元的建筑彩绘纹样图像进行矢量化,并保留图像中可复用图元的独立性与变换参数,提出一种基于图元变换的建筑彩绘纹样图像矢量化方法。该方法首先将复杂彩绘纹样划分为局部纹样;然后对局部纹样进行图元多分类检测,完成... 为了对包含可复用图元的建筑彩绘纹样图像进行矢量化,并保留图像中可复用图元的独立性与变换参数,提出一种基于图元变换的建筑彩绘纹样图像矢量化方法。该方法首先将复杂彩绘纹样划分为局部纹样;然后对局部纹样进行图元多分类检测,完成图元过滤和图元变换参数初始化;再基于改进的可微合成算法计算图元的变换参数;最终完成纹样图像的保留可复用图元变换参数的矢量化。实验结果表明,在建筑彩绘纹样数据集上能够达到较小的图像重建误差,同时保留了可复用图元的变换参数。根据彩绘纹样特点提出了多种矢量化指标,比较了各类方法的性能,该方法在重建精度与图元变换参数保留方面具有优势,可应用于建筑彩绘纹样等具有图元可复用特点的图像矢量化。 展开更多
关键词 图像矢量化 图像模式 残差网络 图像分类 可微图像合成
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基于多层次多尺度注意力融合网络的多模态眼底疾病诊断模型
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作者 郭晓新 杨梅 +2 位作者 杨广奇 董洪良 徐海啸 《吉林大学学报(理学版)》 北大核心 2025年第3期783-794,共12页
针对单模态眼底图像提取眼底特征的局限性,提出一个基于多层次多尺度注意力融合网络的多模态眼底疾病诊断模型.首先,分别针对彩色眼底图像和视网膜光学相干断层成像设计多层次注意力网络和多尺度注意力网络,并在特征层进行融合得到融合... 针对单模态眼底图像提取眼底特征的局限性,提出一个基于多层次多尺度注意力融合网络的多模态眼底疾病诊断模型.首先,分别针对彩色眼底图像和视网膜光学相干断层成像设计多层次注意力网络和多尺度注意力网络,并在特征层进行融合得到融合特征;其次,将两种模态的损失函数加权,与融合特征的损失函数相加,提取模态的独特和互补信息,以提高眼底疾病诊断的准确率.在数据集MMC-AMD和GAMMA上进行评估的实验结果表明,该模型优于当前主流模型,诊断效果优越. 展开更多
关键词 医学图像分类 眼底疾病诊断模型 多模态分类 注意力机制
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融合中心损失和焦点损失的蝴蝶自动识别
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作者 李小林 李建祥 +3 位作者 陈彬彬 王荣 张飞萍 黄世国 《昆虫学报》 北大核心 2025年第2期223-230,共8页
【目的】针对蝴蝶样本存在类间和类内分布不平衡导致识别性能下降的问题,探索一种多损失融合的蝴蝶自动识别方法。【方法】利用开源的Butterfly-200图像数据集作为实验数据。该数据集包括200种蝴蝶,每种蝴蝶的图像数量从30~885不等。以... 【目的】针对蝴蝶样本存在类间和类内分布不平衡导致识别性能下降的问题,探索一种多损失融合的蝴蝶自动识别方法。【方法】利用开源的Butterfly-200图像数据集作为实验数据。该数据集包括200种蝴蝶,每种蝴蝶的图像数量从30~885不等。以交叉熵损失(cross-entropy loss)为基准损失,分别叠加对比损失(contrastive loss)、焦点损失(focal loss)、类平衡损失(class-balanced loss)、采样(sampling)、logit调整(logit adjustment),比较算法的识别性能。在此基础上,利用中心损失(center loss)有助于缓解类内不平衡而焦点损失有助于缓解类内和类间不平衡的特点,开展消融实验分析叠加中心损失和焦点损失对识别性能的影响,提出了融合上述这两种损失的蝴蝶自动识别新方法。【结果】交叉熵损失与其他单一损失(对比损失除外)结合时,算法的识别性能基本上呈现不同程度的下降。我们的算法在交叉熵损失基础上结合中心损失和焦点损失后,其识别性能均超过交叉熵损失及其与其他损失的组合,准确率、F1分值、查准率和召回率分别91.67%,90.68%,91.68%和90.38%。消融试验进一步证实了中心损失和焦点损失的互补性,同时使用这两种损失能明显提升识别性能。此外,不同权重的损失组合对识别性能也有明显影响。【结论】研究结果证明融合中心损失和焦点损失在一定程度上缓解了类间和类内分布不均衡的问题,能够有效提高蝴蝶识别的准确性,为生态环境监测提供了一种有效的辅助手段。 展开更多
关键词 蝴蝶 分布不均衡 交叉熵损失 中心损失 焦点损失 图像分类
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