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RVFLN-based online adaptive semi-supervised learning algorithm with application to product quality estimation of industrial processes 被引量:5
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作者 DAI Wei HU Jin-cheng +2 位作者 CHENG Yu-hu WANG Xue-song CHAI Tian-you 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第12期3338-3350,共13页
Direct online measurement on product quality of industrial processes is difficult to be realized,which leads to a large number of unlabeled samples in modeling data.Therefore,it needs to employ semi-supervised learnin... Direct online measurement on product quality of industrial processes is difficult to be realized,which leads to a large number of unlabeled samples in modeling data.Therefore,it needs to employ semi-supervised learning(SSL)method to establish the soft sensor model of product quality.Considering the slow time-varying characteristic of industrial processes,the model parameters should be updated smoothly.According to this characteristic,this paper proposes an online adaptive semi-supervised learning algorithm based on random vector functional link network(RVFLN),denoted as OAS-RVFLN.By introducing a L2-fusion term that can be seen a weight deviation constraint,the proposed algorithm unifies the offline and online learning,and achieves smoothness of model parameter update.Empirical evaluations both on benchmark testing functions and datasets reveal that the proposed OAS-RVFLN can outperform the conventional methods in learning speed and accuracy.Finally,the OAS-RVFLN is applied to the coal dense medium separation process in coal industry to estimate the ash content of coal product,which further verifies its effectiveness and potential of industrial application. 展开更多
关键词 semi-supervised learning(SSL) L2-fusion term online adaptation random vector functional link network(RVFLN)
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Unsupervised hyperspectral unmixing based on robust nonnegative dictionary learning 被引量:1
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作者 LI Yang JIANG Bitao +2 位作者 LI Xiaobin TIAN Jing SONG Xiaorui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第2期294-304,共11页
Considering the sparsity of hyperspectral images(HSIs),dictionary learning frameworks have been widely used in the field of unsupervised spectral unmixing.However,it is worth mentioning here that existing dictionary l... Considering the sparsity of hyperspectral images(HSIs),dictionary learning frameworks have been widely used in the field of unsupervised spectral unmixing.However,it is worth mentioning here that existing dictionary learning method-based unmixing methods are found to be short of robustness in noisy contexts.To improve the performance,this study specifically puts forward a new unsupervised spectral unmixing solution.For the reason that the solution only functions in a condition that both endmembers and the abundances meet non-negative con-straints,a model is built to solve the unsupervised spectral un-mixing problem on the account of the dictionary learning me-thod.To raise the screening accuracy of final members,a new form of the target function is introduced into dictionary learning practice,which is conducive to the growing robustness of noisy HSI statistics.Then,by introducing the total variation(TV)terms into the proposed spectral unmixing based on robust nonnega-tive dictionary learning(RNDLSU),the context information under HSI space is to be cited as prior knowledge to compute the abundances when performing sparse unmixing operations.Ac-cording to the final results of the experiment,this method makes favorable performance under varying noise conditions,which is especially true under low signal to noise conditions. 展开更多
关键词 hyperspectral image(HSI) nonnegative dictionary learning norm loss function unsupervised unmixing
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A GENERALIZED GOODNESS CRITERION FOR UNSUPERVISED NEURAL LEARNING OF VISUAL PERCEPTION
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作者 Liu Jianqin(College of Information Engineering, Central South University of Technology, Changsha 410083, China) 《Journal of Central South University》 SCIE EI CAS 1996年第2期63-67,共5页
Unsupervised learning plays an important role in the neural networks. Focusing on the unsupervised mechanism of neural networks, a novel generalized goodness criterion for the unsupervised neural learning of visual pe... Unsupervised learning plays an important role in the neural networks. Focusing on the unsupervised mechanism of neural networks, a novel generalized goodness criterion for the unsupervised neural learning of visual perception based on the martingale measure is proposed in the paper. The differential geometrical structure is used as the framework of the whole inference and spatial statistical description with adaptive attribute is embedded in the corresponding nonlinear functional space. Consequently the integration of optimization process and computational simulation with the NeoDarwinian paradigm is obtained. And the generalization of the guidance for the evolutionary learning in the neural net framework, the convergence of the goodness and process of the evolution guaranteed by the mathematical features are discussed. This criterion has generic significance in the field of machine vision and visual pattern classification. 展开更多
关键词 VISUAL PERCEPTION unsupervised learning NEURAL network
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Error assessment of laser cutting predictions by semi-supervised learning
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作者 Mustafa Zaidi Imran Amin +1 位作者 Ahmad Hussain Nukman Yusoff 《Journal of Central South University》 SCIE EI CAS 2014年第10期3736-3745,共10页
Experimentation data of perspex glass sheet cutting, using CO2 laser, with missing values were modelled with semi-supervised artificial neural networks. Factorial design of experiment was selected for the verification... Experimentation data of perspex glass sheet cutting, using CO2 laser, with missing values were modelled with semi-supervised artificial neural networks. Factorial design of experiment was selected for the verification of orthogonal array based model prediction. It shows improvement in modelling of edge quality and kerf width by applying semi-supervised learning algorithm, based on novel error assessment on simulations. The results are expected to depict better prediction on average by utilizing the systematic randomized techniques to initialize the neural network weights and increase the number of initialization. Missing values handling is difficult with statistical tools and supervised learning techniques; on the other hand, semi-supervised learning generates better results with the smallest datasets even with missing values. 展开更多
关键词 semi-supervised learning training algorithm kerf width edge quality laser cutting process artificial neural network(ANN)
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Tomato detection method using domain adaptive learning for dense planting environments 被引量:1
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作者 LI Yang HOU Wenhui +4 位作者 YANG Huihuang RAO Yuan WANG Tan JIN Xiu ZHU Jun 《农业工程学报》 EI CAS CSCD 北大核心 2024年第13期134-145,共12页
This study aimed to address the challenge of accurately and reliably detecting tomatoes in dense planting environments,a critical prerequisite for the automation implementation of robotic harvesting.However,the heavy ... This study aimed to address the challenge of accurately and reliably detecting tomatoes in dense planting environments,a critical prerequisite for the automation implementation of robotic harvesting.However,the heavy reliance on extensive manually annotated datasets for training deep learning models still poses significant limitations to their application in real-world agricultural production environments.To overcome these limitations,we employed domain adaptive learning approach combined with the YOLOv5 model to develop a novel tomato detection model called as TDA-YOLO(tomato detection domain adaptation).We designated the normal illumination scenes in dense planting environments as the source domain and utilized various other illumination scenes as the target domain.To construct bridge mechanism between source and target domains,neural preset for color style transfer is introduced to generate a pseudo-dataset,which served to deal with domain discrepancy.Furthermore,this study combines the semi-supervised learning method to enable the model to extract domain-invariant features more fully,and uses knowledge distillation to improve the model's ability to adapt to the target domain.Additionally,for purpose of promoting inference speed and low computational demand,the lightweight FasterNet network was integrated into the YOLOv5's C3 module,creating a modified C3_Faster module.The experimental results demonstrated that the proposed TDA-YOLO model significantly outperformed original YOLOv5s model,achieving a mAP(mean average precision)of 96.80%for tomato detection across diverse scenarios in dense planting environments,increasing by 7.19 percentage points;Compared with the latest YOLOv8 and YOLOv9,it is also 2.17 and 1.19 percentage points higher,respectively.The model's average detection time per image was an impressive 15 milliseconds,with a FLOPs(floating point operations per second)count of 13.8 G.After acceleration processing,the detection accuracy of the TDA-YOLO model on the Jetson Xavier NX development board is 90.95%,the mAP value is 91.35%,and the detection time of each image is 21 ms,which can still meet the requirements of real-time detection of tomatoes in dense planting environment.The experimental results show that the proposed TDA-YOLO model can accurately and quickly detect tomatoes in dense planting environment,and at the same time avoid the use of a large number of annotated data,which provides technical support for the development of automatic harvesting systems for tomatoes and other fruits. 展开更多
关键词 PLANTS MODELS domain adaptive tomato detection illumination variation semi-supervised learning dense planting environments
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Research on Transfer Learning in Surface Defect Detection of Printed Products 被引量:1
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作者 ZHU Xin-yu SI Zhan-jun CHEN Zhi-yu 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第6期38-44,共7页
To advance the printing manufacturing industry towards intelligence and address the challenges faced by supervised learning,such as the high workload,cost,poor generalization,and labeling issues,an unsupervised and tr... To advance the printing manufacturing industry towards intelligence and address the challenges faced by supervised learning,such as the high workload,cost,poor generalization,and labeling issues,an unsupervised and transfer learning-based method for printing defect detection was proposed in this study.This method enabled defect detection in printed surface without the need for extensive labeled defect.The ResNet101-SSTU model was used in this study.On the public dataset of printing defect images,the ResNet101-SSTU model not only achieves comparable performance and speed to mainstream supervised learning detection models but also successfully addresses some of the detection challenges encountered in supervised learning.The proposed ResNet101-SSTU model effectively eliminates the need for extensive defect samples and labeled data in training,providing an efficient solution for quality inspection in the printing industry. 展开更多
关键词 Transfer learning unsupervised Defect detection PRINTING
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Robust multi-layer extreme learning machine using bias-variance tradeoff 被引量:1
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作者 YU Tian-jun YAN Xue-feng 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第12期3744-3753,共10页
As a new neural network model,extreme learning machine(ELM)has a good learning rate and generalization ability.However,ELM with a single hidden layer structure often fails to achieve good results when faced with large... As a new neural network model,extreme learning machine(ELM)has a good learning rate and generalization ability.However,ELM with a single hidden layer structure often fails to achieve good results when faced with large-scale multi-featured problems.To resolve this problem,we propose a multi-layer framework for the ELM learning algorithm to improve the model’s generalization ability.Moreover,noises or abnormal points often exist in practical applications,and they result in the inability to obtain clean training data.The generalization ability of the original ELM decreases under such circumstances.To address this issue,we add model bias and variance to the loss function so that the model gains the ability to minimize model bias and model variance,thus reducing the influence of noise signals.A new robust multi-layer algorithm called ML-RELM is proposed to enhance outlier robustness in complex datasets.Simulation results show that the method has high generalization ability and strong robustness to noise. 展开更多
关键词 extreme learning machine deep neural network ROBUSTNESS unsupervised feature learning
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Progressive transductive learning pattern classification via single sphere
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作者 Xue Zhenxia Liu Sanyang Liu Wanli 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期643-650,共8页
In many machine learning problems, a large amount of data is available but only a few of them can be labeled easily. This provides a research branch to effectively combine unlabeled and labeled data to infer the label... In many machine learning problems, a large amount of data is available but only a few of them can be labeled easily. This provides a research branch to effectively combine unlabeled and labeled data to infer the labels of unlabeled ones, that is, to develop transductive learning. In this article, based on Pattern classification via single sphere (SSPC), which seeks a hypersphere to separate data with the maximum separation ratio, a progressive transductive pattern classification method via single sphere (PTSSPC) is proposed to construct the classifier using both the labeled and unlabeled data. PTSSPC utilize the additional information of the unlabeled samples and obtain better classification performance than SSPC when insufficient labeled data information is available. Experiment results show the algorithm can yields better performance. 展开更多
关键词 pattern recognition semi-supervised learning transductive learning CLASSIFICATION support vector machine support vector domain description.
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Multi-label dimensionality reduction based on semi-supervised discriminant analysis
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作者 李宏 李平 +1 位作者 郭跃健 吴敏 《Journal of Central South University》 SCIE EI CAS 2010年第6期1310-1319,共10页
Multi-label data with high dimensionality often occurs,which will produce large time and energy overheads when directly used in classification tasks.To solve this problem,a novel algorithm called multi-label dimension... Multi-label data with high dimensionality often occurs,which will produce large time and energy overheads when directly used in classification tasks.To solve this problem,a novel algorithm called multi-label dimensionality reduction via semi-supervised discriminant analysis(MSDA) was proposed.It was expected to derive an objective discriminant function as smooth as possible on the data manifold by multi-label learning and semi-supervised learning.By virtue of the latent imformation,which was provided by the graph weighted matrix of sample attributes and the similarity correlation matrix of partial sample labels,MSDA readily made the separability between different classes achieve maximization and estimated the intrinsic geometric structure in the lower manifold space by employing unlabeled data.Extensive experimental results on several real multi-label datasets show that after dimensionality reduction using MSDA,the average classification accuracy is about 9.71% higher than that of other algorithms,and several evaluation metrices like Hamming-loss are also superior to those of other dimensionality reduction methods. 展开更多
关键词 manifold learning semi-supervised learning (SSL) linear diseriminant analysis (LDA) multi-label classification dimensionality reduction
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基于深度学习的低光照图像增强研究综述 被引量:1
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作者 孙福艳 吕准 吕宗旺 《计算机应用研究》 北大核心 2025年第1期19-27,共9页
低光照图像增强的目的是优化在光线不足的环境中捕获的图像,提升其亮度和对比度。目前,深度学习在低光照图像增强领域已成为主要方法,因此,有必要对基于深度学习的方法进行综述。首先,将传统低光照图像增强方法进行分类,并分析与总结其... 低光照图像增强的目的是优化在光线不足的环境中捕获的图像,提升其亮度和对比度。目前,深度学习在低光照图像增强领域已成为主要方法,因此,有必要对基于深度学习的方法进行综述。首先,将传统低光照图像增强方法进行分类,并分析与总结其优缺点。接着,重点介绍基于深度学习的方法,将其分为有监督和无监督两大类,分别总结其优缺点,随后总结应用在深度学习下的损失函数。其次,对常用的数据集和评价指标进行简要总结,使用信息熵对传统方法进行量化比较,采用峰值信噪比和结构相似性对基于深度学习的方法进行客观评价。最后,总结目前方法存在的不足,并对未来的研究方向进行展望。 展开更多
关键词 低光照图像增强 深度学习 有监督 特征提取 无监督
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基于对比学习的动作识别研究综述
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作者 孙中华 吴双 +2 位作者 贾克斌 冯金超 刘鹏宇 《电子与信息学报》 北大核心 2025年第8期2473-2485,共13页
人体动作具有类别数量多、类内/类间差异不均衡等特性,导致动作识别对数据标签数量与质量的依赖度过高,大幅增加了学习模型的训练成本,而对比学习是解决该问题的有效方法之一,近年来基于对比学习的动作识别逐渐成为研究热点。基于此,该... 人体动作具有类别数量多、类内/类间差异不均衡等特性,导致动作识别对数据标签数量与质量的依赖度过高,大幅增加了学习模型的训练成本,而对比学习是解决该问题的有效方法之一,近年来基于对比学习的动作识别逐渐成为研究热点。基于此,该文全面论述了对比学习在动作识别中的最新进展,将对比学习的研究分为3大阶段:传统对比学习、基于聚类的对比学习以及不使用负样本的对比学习。在每一阶段,首先概述具有代表性的对比学习模型,然后分析了当前基于该类模型的主要动作识别方法。另外,介绍了主流基准数据集,总结了经典方法在数据集上的性能对比。最后,探讨了对比学习模型在动作识别研究中的局限性和可延展之处。 展开更多
关键词 动作识别 对比学习 对比损失 无监督学习
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基于细节增强和多颜色空间学习的联合监督水下图像增强算法
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作者 胡锐 程家亮 胡伏原 《现代电子技术》 北大核心 2025年第1期23-28,共6页
由于水下特殊的成像环境,水下图像往往具有严重的色偏雾化等现象。因此文中根据水下光学成像模型设计了一种新的增强算法,即基于细节增强和多颜色空间学习的无监督水下图像增强算法(UUIE-DEMCSL)。该算法设计了一种基于多颜色空间的增... 由于水下特殊的成像环境,水下图像往往具有严重的色偏雾化等现象。因此文中根据水下光学成像模型设计了一种新的增强算法,即基于细节增强和多颜色空间学习的无监督水下图像增强算法(UUIE-DEMCSL)。该算法设计了一种基于多颜色空间的增强网络,将输入转换为多个颜色空间(HSV、RGB、LAB)进行特征提取,并将提取到的特征融合,使得网络能学习到更多的图像特征信息,从而对输入图像进行更为精确的增强。最后,UUIE-DEMCSL根据水下光学成像模型和联合监督学习框架进行设计,使其更适合水下图像增强任务的应用场景。在不同数据集上大量的实验结果表明,文中提出的UUIE-DEMCSL算法能生成视觉质量良好的水下增强图像,且各项指标具有显著的优势。 展开更多
关键词 水下图像增强 多颜色空间学习 无监督学习 细节增强 特征提取 特征融合
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辽河坳陷西部凹陷雷家地区沙四段杜三层细粒沉积岩储层特征及评价
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作者 李阳 李晓光 +7 位作者 陈昌 崔向东 赖鹏 郭鹏超 任铌 刘洋 戚雪晨 郭美伶 《地学前缘》 北大核心 2025年第2期277-289,共13页
西部凹陷雷家地区沙四段杜三层沉积了以黏土、长英质、碳酸盐和方沸石矿物混合的湖相细粒沉积岩,为该区近年致密油和页岩油勘探重点对象。在前人研究基础上,使用钻井、测井、录井和分析化验等资料,并结合无监督学习方法,对研究区目的层... 西部凹陷雷家地区沙四段杜三层沉积了以黏土、长英质、碳酸盐和方沸石矿物混合的湖相细粒沉积岩,为该区近年致密油和页岩油勘探重点对象。在前人研究基础上,使用钻井、测井、录井和分析化验等资料,并结合无监督学习方法,对研究区目的层细粒沉积岩进行分类,研究细粒岩储层基本地质特征并对其评价和有利区带预测。对303个X射线衍射全岩定量分析数据进行K-means聚类分析,将杜三层岩性划分为碳酸盐岩类、长英质混合细粒岩类和方沸石质混合细粒岩类3种类型,其中碳酸盐岩类和方沸石质混合细粒岩类具有更好的脆性特征,容易产生裂缝,并且溶孔和溶洞沿着裂缝发育,使得此类岩石储渗性能更佳,杜三层储层孔喉半径细小,分选差,均质系数小,孔隙结构较差,形成有效储层依赖微孔隙和微裂缝。基于叠合概率评价方法,将脆性指数、碳酸盐岩和方沸石质混合细粒岩厚度、裂缝密度、平均孔隙度、平均渗透率和总有机碳含量6种影响储层发育因素进行融合并评价,储层发育有利区沿湖盆长轴雷15井—雷84井—雷59井—曙90井—雷93井等井区分布。 展开更多
关键词 辽河坳陷 西部凹陷 细粒沉积岩 无监督学习 叠合概率 储层评价
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基于改进SOM网络的聚类算法
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作者 蒋锐 范姝文 +1 位作者 王小明 徐友云 《计算机科学》 北大核心 2025年第8期162-170,共9页
在自组织映射(Self-organizing Map,SOM)模型的训练过程中,不同类数据对权重矩阵的更新有不同作用,某一类数据对权重矩阵的更新会对其他类获胜神经元特征向量产生偏离其数据特征的影响,从而降低算法聚类精度。针对以上问题,提出一种改... 在自组织映射(Self-organizing Map,SOM)模型的训练过程中,不同类数据对权重矩阵的更新有不同作用,某一类数据对权重矩阵的更新会对其他类获胜神经元特征向量产生偏离其数据特征的影响,从而降低算法聚类精度。针对以上问题,提出一种改进的基于置信度SOM模型(Improved Confidence-based SOM Model,icSOM)。样本数据首先由K-means算法初步分类,为模型训练提供更多的数据信息;然后将预分类后的数据分别训练相互独立的SOM模型,以消除不同类之间的影响;最后在传统SOM模型基础上提出置信度矩阵概念,通过综合判断获胜神经元的置信度及其与输入数据间的欧氏距离最终得到置信神经元,根据置信神经元所属类别给数据分配聚类标签。在鸢尾花数据集(Iris)及葡萄酒数据集(Wine)上利用icSOM进行聚类分析,实验结果表明,所提算法可以更好地处理样本数据,取得了较好的聚类效果。 展开更多
关键词 机器学习 无监督学习 聚类 自组织特征映射神经网络
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复杂噪声下基于鲁棒增强TimesNet的换流阀声纹异常检测
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作者 唐明珠 俞昱 +5 位作者 左佳文 吴华伟 尹琛 魏颖 潘舒妍 熊富强 《南方电网技术》 北大核心 2025年第6期4-13,50,共11页
在电力系统中,实时监测换流阀的健康状态对于确保整个系统的可靠性与安全性至关重要。与传统的振动信号分析、温度监测等检测手段相比,声纹检测具有无接触、低成本等优势,然而在复杂多变的换流阀非本体背景噪声环境下,声纹异常检测模型... 在电力系统中,实时监测换流阀的健康状态对于确保整个系统的可靠性与安全性至关重要。与传统的振动信号分析、温度监测等检测手段相比,声纹检测具有无接触、低成本等优势,然而在复杂多变的换流阀非本体背景噪声环境下,声纹异常检测模型的性能往往达不到工业要求。针对该问题,提出了一种基于鲁棒增强TimesNet(RE-TimesNet)的换流阀声纹异常检测方法。该方法首先提取声纹数据的声学特征及其特征差分。然后,将特征集进行时频域掩码,进一步增强了特征集的鲁棒性。最后,采用基于Huber损失函数结合L2正则项和分组卷积的改进TimesNet异常检测模型识别异常模式。实验结果表明,RE-TimesNet在提高换流阀声纹异常检测的准确性、鲁棒性和运行速度方面具有显著的优势,能够缓解过拟合且轻量化神经网络模型。该方法为噪声环境下的换流阀声纹异常检测提供了有效的解决方案。 展开更多
关键词 换流阀 声纹 异常检测 特征工程 鲁棒性 无监督学习
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基于多层特征融合与增强的对比图聚类
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作者 李志明 魏贺萍 +1 位作者 张广康 尤殿龙 《计算机应用研究》 北大核心 2025年第6期1749-1754,共6页
现有大多数对比图聚类算法存在以下问题:生成节点表示时忽略了浅层网络提取的底层特征和底层结构信息;未充分利用高阶邻居节点信息;未结合置信度信息与拓扑结构信息来构建正样本对。为解决以上问题,提出了基于多层特征融合与增强的对比... 现有大多数对比图聚类算法存在以下问题:生成节点表示时忽略了浅层网络提取的底层特征和底层结构信息;未充分利用高阶邻居节点信息;未结合置信度信息与拓扑结构信息来构建正样本对。为解决以上问题,提出了基于多层特征融合与增强的对比图聚类算法。该算法首先融合不同层次网络提取的节点特征,以补充节点的底层结构信息;其次,通过节点间的局部拓扑相关性和全局语义相似度聚合节点信息,以增强节点表示的上下文约束一致性;最后,联合置信度信息和拓扑结构信息构建更多高质量正样本对,提高簇内表示一致性。实验结果表明,CGCMFFE在四种广泛使用的聚类评价指标上表现出优异的性能。理论分析和实验研究验证了CGCMFFE中节点底层特征、高阶邻居节点信息、置信度和拓扑结构信息的关键作用,证明了CGCMFFE的优越性。 展开更多
关键词 多层特征融合 对比图聚类 无监督学习
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基于线性-对数响应相机的HDR图像融合算法
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作者 张磊 柳凯元 +1 位作者 李昱天石 常玉春 《液晶与显示》 北大核心 2025年第7期1046-1055,共10页
针对高动态范围(High Dynamic Range,HDR)图像生成任务,为了解决现有方法存在的多曝光图像采集时间长、动态场景存在帧间偏移、算法参数量及计算量大等问题,本文基于线性对数响应相机,提出了一种轻量化的HDR图像融合算法,并采集了一个... 针对高动态范围(High Dynamic Range,HDR)图像生成任务,为了解决现有方法存在的多曝光图像采集时间长、动态场景存在帧间偏移、算法参数量及计算量大等问题,本文基于线性对数响应相机,提出了一种轻量化的HDR图像融合算法,并采集了一个多增益灰度图像数据集。首先,使用改进的多尺度残差模块提取输入图像的多层次特征并提升特征维度;其次,将多层次特征输入引入深度可分离卷积的Attention-UNet结构中,提取特征中多层次信息并对特征进行融合;再次,使用逐点卷积对图像的深度特征进行融合,输出兼容标准显示设备的高动态范围图像,无需额外的色调映射;最后,比较各消融结构的性能及参数量和计算量,得到在保证融合效果的同时又使网络轻量化的最优解。实验结果表明,本文提出的算法在主观视觉效果和客观评价指标方面均具有较好表现,MEF-SSIM为0.9866,视觉保真度为1.76,平均梯度为3.94,空间频率为14.32。本文提出的高动态图像融合算法在多增益图像间存在显著差异的情况下仍能保持优异的融合效果和鲁棒性,且具有轻量化的特点,模型参数量仅为0.612M,计算复杂度为7.254 GFLOPs。 展开更多
关键词 高动态图像 图像融合 无监督学习 注意力机制 轻量化
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联合不相关回归和潜在表示的无监督特征选择
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作者 刘威 朱乙鑫 +2 位作者 白润才 高琪 李晓红 《辽宁工程技术大学学报(自然科学版)》 北大核心 2025年第4期495-504,共10页
针对基于图的无监督特征选择算法存在挖掘数据内在信息不充分,且易受噪声干扰难以获取更具有判别性特征的问题,提出一种基于广义不相关回归和潜在表示学习的无监督特征选择方法(uncorrelated regression and latent representation for ... 针对基于图的无监督特征选择算法存在挖掘数据内在信息不充分,且易受噪声干扰难以获取更具有判别性特征的问题,提出一种基于广义不相关回归和潜在表示学习的无监督特征选择方法(uncorrelated regression and latent representation for unsupervised feature selection,URLUFS)。该方法将非负矩阵分解作用于广义不相关回归模型的投影矩阵,使投影矩阵实现非线性的维数约简并获得特征选择矩阵。在特征选择矩阵的基础上,引入自适应图学习来进一步挖掘数据的局部流形结构,并对特征选择矩阵施加范数约束以保持稀疏性。利用潜在表示对数据样本间的相互关系进行学习,引导回归模型中的伪标签矩阵,从而选择出更具有判别性的特征。在8个公开的数据集上进行了数值对比实验,实验结果表明:基于广义不相关回归和潜在表示学习的无监督特征选择算法明显优于其他8种无监督特征选择算法。 展开更多
关键词 无监督特征选择 广义不相关回归 非负矩阵分解 潜在表示学习 自适应图学习
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基于RBM无监督学习模型的图像数据去噪
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作者 沈卉卉 李宏伟 钱坤 《计算机辅助设计与图形学学报》 北大核心 2025年第1期167-175,共9页
已有的受限Boltzmann机(restricted Boltzmann machine,RBM)模型去噪方法完全基于它是无向图模型,多个RBM组合模型,其低层的分布依赖于高层的分布,会导致计算复杂,去噪效果也一般,应用难以推广.为解决这一问题,提出基于RBM模型的深度信... 已有的受限Boltzmann机(restricted Boltzmann machine,RBM)模型去噪方法完全基于它是无向图模型,多个RBM组合模型,其低层的分布依赖于高层的分布,会导致计算复杂,去噪效果也一般,应用难以推广.为解决这一问题,提出基于RBM模型的深度信念网络(deep belief nets,DBN)的图像数据随机噪声去除的方法.将原始图像加入随机噪声,把带噪声的图像分割若干小块,将其一一拉成向量;批量输入2个隐层的DBN模型中进行学习,原始图像作为标签进行反向微调;最后将其学习的特征输出,还原成图像,即达到消除随机噪声的目的.将DBN模型分别在自然图像数据、模拟的地震数据和真实的地震数据上进行随机噪声去除实验,实验结果表明,提出的基于RBM模型的DBN在自然图像数据和地震数据上去噪方法可行的.在噪声标准差为50 dB时,Set12数据集中图像去噪后峰值信噪比至少提高2.08 dB,至少提高6.99%;且在不同噪声标准差下,该方法去除随机噪声效果均优于其他无监督学习算法和卷积神经网络等深度学习方法,说明RBM模型在图像特征学习性能、本质特征提取上有很强的能力.也为工程领域中的图像去噪方法提供了一种新的研究思路和借鉴. 展开更多
关键词 受限Boltzmann机 无监督学习 RBM模型 图像去噪 随机噪声
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基于扩散模型的遥感图像变化检测方法
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作者 李克文 蒋衡杰 +2 位作者 李国庆 姚贤哲 刘文龙 《计算机工程与设计》 北大核心 2025年第2期337-344,共8页
针对遥感图像人工标注耗时且昂贵的缺点,提出一种两阶段的变化检测方法。通过预训练去噪扩散概率模型来利用这些现成的、未标注的遥感图像信息,利用从扩散模型主干网络U-Net的后半部分编码器中获取的多尺度特征来训练一个轻量级的变化... 针对遥感图像人工标注耗时且昂贵的缺点,提出一种两阶段的变化检测方法。通过预训练去噪扩散概率模型来利用这些现成的、未标注的遥感图像信息,利用从扩散模型主干网络U-Net的后半部分编码器中获取的多尺度特征来训练一个轻量级的变化检测头部。通过同时处理不同加噪时间步的遥感图像,基于噪声水平进行加权融合进一步提升模型对变化相关信息的敏感性。在LEVIR-CD和WHU-CD数据集上的对比实验结果表明,该方法有效提高了识别精度。 展开更多
关键词 变化检测 深度学习 预训练 特征融合 特征提取 扩散模型 无监督训练
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