期刊文献+
共找到4,670篇文章
< 1 2 234 >
每页显示 20 50 100
Tomato Growth Height Prediction Method by Phenotypic Feature Extraction Using Multi-modal Data
1
作者 GONG Yu WANG Ling +3 位作者 ZHAO Rongqiang YOU Haibo ZHOU Mo LIU Jie 《智慧农业(中英文)》 2025年第1期97-110,共14页
[Objective]Accurate prediction of tomato growth height is crucial for optimizing production environments in smart farming.However,current prediction methods predominantly rely on empirical,mechanistic,or learning-base... [Objective]Accurate prediction of tomato growth height is crucial for optimizing production environments in smart farming.However,current prediction methods predominantly rely on empirical,mechanistic,or learning-based models that utilize either images data or environmental data.These methods fail to fully leverage multi-modal data to capture the diverse aspects of plant growth comprehensively.[Methods]To address this limitation,a two-stage phenotypic feature extraction(PFE)model based on deep learning algorithm of recurrent neural network(RNN)and long short-term memory(LSTM)was developed.The model integrated environment and plant information to provide a holistic understanding of the growth process,emploied phenotypic and temporal feature extractors to comprehensively capture both types of features,enabled a deeper understanding of the interaction between tomato plants and their environment,ultimately leading to highly accurate predictions of growth height.[Results and Discussions]The experimental results showed the model's ef‐fectiveness:When predicting the next two days based on the past five days,the PFE-based RNN and LSTM models achieved mean absolute percentage error(MAPE)of 0.81%and 0.40%,respectively,which were significantly lower than the 8.00%MAPE of the large language model(LLM)and 6.72%MAPE of the Transformer-based model.In longer-term predictions,the 10-day prediction for 4 days ahead and the 30-day prediction for 12 days ahead,the PFE-RNN model continued to outperform the other two baseline models,with MAPE of 2.66%and 14.05%,respectively.[Conclusions]The proposed method,which leverages phenotypic-temporal collaboration,shows great potential for intelligent,data-driven management of tomato cultivation,making it a promising approach for enhancing the efficiency and precision of smart tomato planting management. 展开更多
关键词 tomato growth prediction deep learning phenotypic feature extraction multi-modal data recurrent neural net‐work long short-term memory large language model
在线阅读 下载PDF
Nonlinear industrial process fault diagnosis with latent label consistency and sparse Gaussian feature learning
2
作者 LI Xian-ling ZHANG Jian-feng +2 位作者 ZHAO Chun-hui DING Jin-liang SUN You-xian 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第12期3956-3973,共18页
With the increasing complexity of industrial processes, the high-dimensional industrial data exhibit a strong nonlinearity, bringing considerable challenges to the fault diagnosis of industrial processes. To efficient... With the increasing complexity of industrial processes, the high-dimensional industrial data exhibit a strong nonlinearity, bringing considerable challenges to the fault diagnosis of industrial processes. To efficiently extract deep meaningful features that are crucial for fault diagnosis, a sparse Gaussian feature extractor(SGFE) is designed to learn a nonlinear mapping that projects the raw data into the feature space with the fault label dimension. The feature space is described by the one-hot encoding of the fault category label as an orthogonal basis. In this way, the deep sparse Gaussian features related to fault categories can be gradually learned from the raw data by SGFE. In the feature space,the sparse Gaussian(SG) loss function is designed to constrain the distribution of features to multiple sparse multivariate Gaussian distributions. The sparse Gaussian features are linearly separable in the feature space, which is conducive to improving the accuracy of the downstream fault classification task. The feasibility and practical utility of the proposed SGFE are verified by the handwritten digits MNIST benchmark and Tennessee-Eastman(TE) benchmark process,respectively. 展开更多
关键词 nonlinear fault diagnosis multiple multivariate Gaussian distributions sparse Gaussian feature learning Gaussian feature extractor
在线阅读 下载PDF
Lazy learner text categorization algorithm based on embedded feature selection 被引量:1
3
作者 Yan Peng Zheng Xuefeng +1 位作者 Zhu Jianyong Xiao Yunhong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期651-659,共9页
To avoid the curse of dimensionality, text categorization (TC) algorithms based on machine learning (ML) have to use an feature selection (FS) method to reduce the dimensionality of feature space. Although havin... To avoid the curse of dimensionality, text categorization (TC) algorithms based on machine learning (ML) have to use an feature selection (FS) method to reduce the dimensionality of feature space. Although having been widely used, FS process will generally cause information losing and then have much side-effect on the whole performance of TC algorithms. On the basis of the sparsity characteristic of text vectors, a new TC algorithm based on lazy feature selection (LFS) is presented. As a new type of embedded feature selection approach, the LFS method can greatly reduce the dimension of features without any information losing, which can improve both efficiency and performance of algorithms greatly. The experiments show the new algorithm can simultaneously achieve much higher both performance and efficiency than some of other classical TC algorithms. 展开更多
关键词 machine learning text categorization embedded feature selection lazy learner cosine similarity.
在线阅读 下载PDF
基于Deep Learning的代词指代消解 被引量:23
4
作者 奚雪峰 周国栋 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2014年第1期100-110,共11页
针对指代消解一直是自然语言处理中的核心问题,提出一种利用DBN(deep belief nets)模型的Deep Learning学习机制进行基于语义特征的指代消解方法。DBN模型由多层无监督的RBM(restricted Boltzmann machine)网络和一层有监督的BP(back-pr... 针对指代消解一直是自然语言处理中的核心问题,提出一种利用DBN(deep belief nets)模型的Deep Learning学习机制进行基于语义特征的指代消解方法。DBN模型由多层无监督的RBM(restricted Boltzmann machine)网络和一层有监督的BP(back-propagation)网络组成,RBM网络确保特征向量映射达到最优,最后一层BP网络可以对RBM网络的输出特征向量进行分类,从而训练指代消解分类器。在ACE04英文语料及ACE05中文语料上进行测试,实验结果表明,增加RBM训练层数可以提高系统性能。此外,引入对特征集合的抽象分层因素,也对系统性能的提升产生积极作用。 展开更多
关键词 代词消解 深度学习 深层语义特征
在线阅读 下载PDF
面向对象影像信息提取软件Feature Analyst和eCognition的分析与比较 被引量:17
5
作者 牛春盈 江万寿 +1 位作者 黄先锋 谢俊峰 《遥感信息》 CSCD 2007年第2期66-70,I0005,共6页
介绍了目前最为先进的两种面向对象的影像信息提取软件Feature Analyst和eCognition。通过对两种软件设计思路、工作流程和软件特殊性的对比分析,探讨了影像信息自动提取的发展趋势。
关键词 面向对象 高分辨率遥感影像 信息提取 feature ANALYST ECOGNITION 机器学习
在线阅读 下载PDF
Cooperative multi-target hunting by unmanned surface vehicles based on multi-agent reinforcement learning 被引量:2
6
作者 Jiawei Xia Yasong Luo +3 位作者 Zhikun Liu Yalun Zhang Haoran Shi Zhong Liu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第11期80-94,共15页
To solve the problem of multi-target hunting by an unmanned surface vehicle(USV)fleet,a hunting algorithm based on multi-agent reinforcement learning is proposed.Firstly,the hunting environment and kinematic model wit... To solve the problem of multi-target hunting by an unmanned surface vehicle(USV)fleet,a hunting algorithm based on multi-agent reinforcement learning is proposed.Firstly,the hunting environment and kinematic model without boundary constraints are built,and the criteria for successful target capture are given.Then,the cooperative hunting problem of a USV fleet is modeled as a decentralized partially observable Markov decision process(Dec-POMDP),and a distributed partially observable multitarget hunting Proximal Policy Optimization(DPOMH-PPO)algorithm applicable to USVs is proposed.In addition,an observation model,a reward function and the action space applicable to multi-target hunting tasks are designed.To deal with the dynamic change of observational feature dimension input by partially observable systems,a feature embedding block is proposed.By combining the two feature compression methods of column-wise max pooling(CMP)and column-wise average-pooling(CAP),observational feature encoding is established.Finally,the centralized training and decentralized execution framework is adopted to complete the training of hunting strategy.Each USV in the fleet shares the same policy and perform actions independently.Simulation experiments have verified the effectiveness of the DPOMH-PPO algorithm in the test scenarios with different numbers of USVs.Moreover,the advantages of the proposed model are comprehensively analyzed from the aspects of algorithm performance,migration effect in task scenarios and self-organization capability after being damaged,the potential deployment and application of DPOMH-PPO in the real environment is verified. 展开更多
关键词 Unmanned surface vehicles Multi-agent deep reinforcement learning Cooperative hunting feature embedding Proximal policy optimization
在线阅读 下载PDF
Robust multi-layer extreme learning machine using bias-variance tradeoff 被引量:1
7
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
在线阅读 下载PDF
Detecting Local Manifold Structure for Unsupervised Feature Selection 被引量:3
8
作者 FENG Ding-Cheng 《自动化学报》 EI CSCD 北大核心 2014年第10期2253-2261,共9页
关键词 特征选择 管结构 流形 监督 拉普拉斯算子 局部线性嵌入 特征值分解 特征子集
在线阅读 下载PDF
Video learning based image classification method for object recognition
9
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
在线阅读 下载PDF
Machine-learning-aided precise prediction of deletions with next-generation sequencing
10
作者 管瑞 髙敬阳 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第12期3239-3247,共9页
When detecting deletions in complex human genomes,split-read approaches using short reads generated with next-generation sequencing still face the challenge that either false discovery rate is high,or sensitivity is l... When detecting deletions in complex human genomes,split-read approaches using short reads generated with next-generation sequencing still face the challenge that either false discovery rate is high,or sensitivity is low.To address the problem,an integrated strategy is proposed.It organically combines the fundamental theories of the three mainstream methods(read-pair approaches,split-read technologies and read-depth analysis) with modern machine learning algorithms,using the recipe of feature extraction as a bridge.Compared with the state-of-art split-read methods for deletion detection in both low and high sequence coverage,the machine-learning-aided strategy shows great ability in intelligently balancing sensitivity and false discovery rate and getting a both more sensitive and more precise call set at single-base-pair resolution.Thus,users do not need to rely on former experience to make an unnecessary trade-off beforehand and adjust parameters over and over again any more.It should be noted that modern machine learning models can play an important role in the field of structural variation prediction. 展开更多
关键词 next-generation sequencing deletion prediction sensitivity false discovery rate feature extraction machine learning
在线阅读 下载PDF
Parallel solving model for quantified boolean formula based on machine learning
11
作者 李涛 肖南峰 《Journal of Central South University》 SCIE EI CAS 2013年第11期3156-3165,共10页
A new parallel architecture for quantified boolean formula(QBF)solving was proposed,and the prediction model based on machine learning technology was proposed for how sharing knowledge affects the solving performance ... A new parallel architecture for quantified boolean formula(QBF)solving was proposed,and the prediction model based on machine learning technology was proposed for how sharing knowledge affects the solving performance in QBF parallel solving system,and the experimental evaluation scheme was also designed.It shows that the characterization factor of clause and cube influence the solving performance markedly in our experiment.At the same time,the heuristic machine learning algorithm was applied,support vector machine was chosen to predict the performance of QBF parallel solving system based on clause sharing and cube sharing.The relative error of accuracy for prediction can be controlled in a reasonable range of 20%30%.The results show the important and complex role that knowledge sharing plays in any modern parallel solver.It shows that the parallel solver with machine learning reduces the quantity of knowledge sharing about 30%and saving computational resource but does not reduce the performance of solving system. 展开更多
关键词 machine learning quantified boolean formula parallel solving knowledge sharing feature extraction performance prediction
在线阅读 下载PDF
A new formant feature and its application in Mandarin vowel pronunciation quality assessment
12
作者 卢小春 潘复平 +1 位作者 尹俊勋 胡维平 《Journal of Central South University》 SCIE EI CAS 2013年第12期3573-3581,共9页
In order to improve the Mandarin vowel pronunciation quality assessment, a nox/el formant feature was proposed and applied to formant classification for Chinese Mandarin vowel pronunciation quality evaluation. Formant... In order to improve the Mandarin vowel pronunciation quality assessment, a nox/el formant feature was proposed and applied to formant classification for Chinese Mandarin vowel pronunciation quality evaluation. Formant candidates of each frame were plotted on the time-frequency plane to form a bitmap, and its Gabor feature was extracted to represent the formant trajectory. The feature was then classified by using GMM model and the classification posterior probability was mapped to pronunciation quality grade. The experiments of comparing the Gabor transformation based formant trajectory feature with several other kinds of traditionally used features show that with this method, a human-machine scoring correlation coefficient (CC) of 0.842 can be achieved, which is better than the result of 0.832 by traditional speech recognition techniques. At the same time, considering that the long-term information of formant classification and the short-term information of speech recognition technique are complementary to each other, it is investigated to combine their results with linear or nonlinear methods to further improve the evaluation performance. As a result, experiments on PSK show that the best CC of 0.913, which is very close to the correlation of inter-human rating of 0.94, is gotten by using neural network. 展开更多
关键词 computer assisted language learning speech recognition Gaussian mixture model FORMANT Gabor feature NEURALNETWORK
在线阅读 下载PDF
一种基于Meta-learning改进的特征交互算法
13
作者 白静 耿新宇 +3 位作者 易流 穆禹锟 陈琴 宋杰 《计算机科学》 CSCD 北大核心 2023年第S02期606-613,共8页
特征交互在推荐系统领域的广告点击率(Click-Through Rate,CTR)预测任务中至关重要,当前业界做的特征交互往往是基于内积、外积等矩阵变换,这些操作没有引入额外的信息,可以作为衡量两个向量相似性的手段,但作为特征交互的表示不一定是... 特征交互在推荐系统领域的广告点击率(Click-Through Rate,CTR)预测任务中至关重要,当前业界做的特征交互往往是基于内积、外积等矩阵变换,这些操作没有引入额外的信息,可以作为衡量两个向量相似性的手段,但作为特征交互的表示不一定是可靠的,许多特征交互无法有效提高点击率预测性能。首先从改善特征交互方式的角度入手引入额外的参数来学习一个映射,假设这个映射能够将两个向量的表征映射成交互的表征。学习映射的过程能够通过元学习(Meta-learning)来实现,故构建一个学习器以函数的方式表征特征交互。另外,不同的特征对不一定采取相同的方式交互,不能通过同一种交互方式得到所有特征对,因此设计一组元学习器(meta-learner)来学习映射函数,引入门控网络(GateNet)学习模型中元学习器的分布,那么不同的特征嵌入可以由一组元学习器得到表征。基于以上两点提出了一种融合多个元学习器并结合门控网络(Multiple meta-learners combined with GateNet,gate-MML)的特征交互算法,通过学习不同特征的联系和差异提高每个特征交互的质量。为了验证所提算法的性能,在xDeepFM模型上采用gate-MML做进一步的特征交互,采用2个真实广告点击率预测的数据集进行实验,并使用Logloss作为损失函数,AUC作为评价指标。实验结果表明与传统的CTR预测模型相比,改进算法提升了广告点击率预测任务的预测性能。 展开更多
关键词 特征交互 广告点击率预测 元学习 门控网络 推荐系统
在线阅读 下载PDF
基于特征筛选和粒子群优化的花生生物量估算 被引量:2
14
作者 刘涛 杨奉源 +4 位作者 刘望 张寰 殷冬梅 张全国 焦有宙 《农业工程学报》 北大核心 2025年第1期238-247,共10页
为解决花生植株生物量估算精度低、破坏性大等问题,该研究提出一种无人机低空遥感技术结合高光谱特征筛选的花生生物量估算方法。通过无人机搭载高光谱成像仪,获取田块尺度多个花生品种的高光谱影像数据,首先对获取的影像进行拼接、辐... 为解决花生植株生物量估算精度低、破坏性大等问题,该研究提出一种无人机低空遥感技术结合高光谱特征筛选的花生生物量估算方法。通过无人机搭载高光谱成像仪,获取田块尺度多个花生品种的高光谱影像数据,首先对获取的影像进行拼接、辐射定标、大气校正等预处理,提取出地面采样点位置的光谱反射率,计算光谱反射率的一阶微分和植被指数,使用变量投影重要性(variable importance in projection,VIP)方法对光谱反射率、一阶微分和植被指数等三种数据进行特征筛选,利用筛选后的特征和地面实测数据构建支持向量机回归(support vector regression,SVR)、反向传播神经网络回归(back propagation neural network,BPNN)和随机森林回归(random forest regression,RFR)模型,并使用粒子群优化算法(particle swarm optimization,PSO)进行模型优化。结果表明:相比原始光谱反射率和植被指数,一阶微分光谱反射率与花生生物量具有较好的相关性;使用一阶微分光谱反射率与植被指数组合的RF回归模型精度最高(决定系数R^(2)为0.754,均方根误差RMSE为0.085 kg/m^(2)),使用粒子群优化后的PSO-RF模型可进一步提高模型精度(R^(2)为0.80,RMSE为0.076 kg/m^(2))。该研究为花生生物量精准估算提供了有效的方法,为智慧乡村建设中的精细化农田管理提供技术支持。 展开更多
关键词 花生 生物量 智慧乡村 特征筛选 机器学习 粒子群优化
在线阅读 下载PDF
Robust signal recognition algorithm based on machine learning in heterogeneous networks
15
作者 Xiaokai Liu Rong Li +1 位作者 Chenglin Zhao Pengbiao Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第2期333-342,共10页
There are various heterogeneous networks for terminals to deliver a better quality of service. Signal system recognition and classification contribute a lot to the process. However, in low signal to noise ratio(SNR)... There are various heterogeneous networks for terminals to deliver a better quality of service. Signal system recognition and classification contribute a lot to the process. However, in low signal to noise ratio(SNR) circumstances or under time-varying multipath channels, the majority of the existing algorithms for signal recognition are already facing limitations. In this series, we present a robust signal recognition method based upon the original and latest updated version of the extreme learning machine(ELM) to help users to switch between networks. The ELM utilizes signal characteristics to distinguish systems. The superiority of this algorithm lies in the random choices of hidden nodes and in the fact that it determines the output weights analytically, which result in lower complexity. Theoretically, the algorithm tends to offer a good generalization performance at an extremely fast speed of learning. Moreover, we implement the GSM/WCDMA/LTE models in the Matlab environment by using the Simulink tools. The simulations reveal that the signals can be recognized successfully to achieve a 95% accuracy in a low SNR(0 dB) environment in the time-varying multipath Rayleigh fading channel. 展开更多
关键词 heterogeneous networks automatic signal classification extreme learning machine(ELM) features-extracted Rayleigh fading channel
在线阅读 下载PDF
多尺度特征提取与融合的红外图像增强算法 被引量:3
16
作者 李牧 张一朗 柯熙政 《红外与激光工程》 北大核心 2025年第2期240-253,共14页
针对传统的特征融合算法多从单一的尺度上抽取图像的特征,并且在红外图像亮度增强过程中可能导致局部特征信息的丢失与退化而引起红外图像细节分辨率不高的问题,提出了多尺度特征提取与融合的红外图像增强算法,主要由多尺度自适应特征... 针对传统的特征融合算法多从单一的尺度上抽取图像的特征,并且在红外图像亮度增强过程中可能导致局部特征信息的丢失与退化而引起红外图像细节分辨率不高的问题,提出了多尺度特征提取与融合的红外图像增强算法,主要由多尺度自适应特征提取模块、亮度增强迭代函数以及特征融合和图像重建模块构成。首先,提出的多尺度自适应特征提取融合模块保存和融合了来自不同卷积层特征的多尺度信息;然后,改进的亮度增强迭代函数使用了融合特征作为逐像素参数,用于红外图像亮度增强;最后,通过提出的特征融合和图像重建模块,增强了特征在网络中的传播能力,并保持了局部信息的完整性。实验结果表明:多尺度特征提取与融合的红外图像增强算法与其它表现较好的网络相比,峰值信噪比、余弦相似度以及信息熵分别提高了3.7%、1.3%、1.6%。且在测试数据集上根据引用的火灾隐患检测算法判断是否存在火灾隐患进行早期火灾检测,其准确率为97.86%,说明了提出的多尺度特征提取与融合的红外图像增强算法的有效性与可行性。 展开更多
关键词 红外图像 图像增强 深度学习 特征融合 注意力机制
在线阅读 下载PDF
基于深度学习的低光照图像增强研究综述 被引量:1
17
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
在线阅读 下载PDF
联邦原型学习的特征图中毒攻击和双重防御机制 被引量:2
18
作者 王瑞锦 王金波 +3 位作者 张凤荔 李经纬 李增鹏 陈厅 《软件学报》 北大核心 2025年第3期1355-1374,共20页
联邦学习是一种无需用户共享私有数据、以分布式迭代协作训练全局机器学习模型的框架.目前流行的联邦学习方法FedProto采用抽象类原型(称为特征图)聚合,优化模型收敛速度和泛化能力.然而,该方法未考虑所聚合的特征图的正确性,而错误的... 联邦学习是一种无需用户共享私有数据、以分布式迭代协作训练全局机器学习模型的框架.目前流行的联邦学习方法FedProto采用抽象类原型(称为特征图)聚合,优化模型收敛速度和泛化能力.然而,该方法未考虑所聚合的特征图的正确性,而错误的特征图可能导致模型训练失效.为此,首先探索针对FedProto的特征图中毒攻击,论证攻击者只需通过置乱训练数据的标签,便可将模型的推测准确率至多降低81.72%.为了抵御上述攻击,进一步提出双重防御机制,分别通过全知识蒸馏和特征图甄别排除错误的特征图.基于真实数据集的实验表明,防御机制可将受攻击模型的推测准确率提升1-5倍,且仅增加2%系统运行时间. 展开更多
关键词 联邦学习 数据异构 知识蒸馏 特征图中毒攻击 双重防御机制
在线阅读 下载PDF
轻量化的多尺度注意力脊柱侧弯筛查方法 被引量:1
19
作者 郝子强 唐颖 +2 位作者 田芳 张岩 詹伟达 《计算机工程与应用》 北大核心 2025年第3期286-294,共9页
近年来,深度学习越来越多地应用于脊柱侧弯筛查技术研究,并且取得了突出的成效。为了解决脊柱侧弯筛查的精度和效率不高,无法满足大规模脊柱侧弯筛查需要的问题,设计了一种轻量化的多尺度注意力卷积神经网络,对ResNet50进行改进,取得了... 近年来,深度学习越来越多地应用于脊柱侧弯筛查技术研究,并且取得了突出的成效。为了解决脊柱侧弯筛查的精度和效率不高,无法满足大规模脊柱侧弯筛查需要的问题,设计了一种轻量化的多尺度注意力卷积神经网络,对ResNet50进行改进,取得了较好的筛查效果。提出了一种多尺度残差特征提取模块,使用不同大小的卷积核,提取不同尺度的信息;使用三个残差块并在残差块中使用一种混合注意力机制,关注通道和空间两方面的信息,增强特征提取能力;将普通卷积替换成一种深度混洗卷积,在精度损失不多的情况下,提高网络效率;提出了一种多层次特征融合模块,将多个层次信息进行特征融合,提取更加多样化的特征信息。实验证明,相比ResNet50总体准确率提高了11.19个百分点,测试时长减少了2 s。 展开更多
关键词 脊柱侧弯 深度学习 多尺度特征 注意力机制
在线阅读 下载PDF
一种基于元学习的改进YOLO钢管表面缺陷小样本检测模型 被引量:2
20
作者 李凌波 田彦 +1 位作者 江旭东 董宝力 《机电工程》 北大核心 2025年第5期985-993,共9页
针对产品表面缺陷样本数稀缺时的深度学习缺陷检测效果不佳问题,提出了一种基于元学习策略的改进YOLO-SBN模型,用于小样本缺陷检测。首先,为了提高提取全局特征信息的能力,采用了Swin Transformer作为骨干网络模型,引入注意力机制提取... 针对产品表面缺陷样本数稀缺时的深度学习缺陷检测效果不佳问题,提出了一种基于元学习策略的改进YOLO-SBN模型,用于小样本缺陷检测。首先,为了提高提取全局特征信息的能力,采用了Swin Transformer作为骨干网络模型,引入注意力机制提取了特征图的判别能力;然后,为了提高特征融合能力并降低计算复杂度,通过加权双向特征金字塔网络(BiFPN)结构优化了特征提取器的颈部网络,平衡了YOLO-SBN模型的有效性和效率;最后,采用归一化注意力模块(NAM)优化权重调整了模块,增强了浅层缺陷特征的模型表达,并基于这些增强的特征进行了检测;使用金属表面热轧缺陷公开数据集NEU-DET验证了YOLO-SBN模型的算法性能。研究结果表明:对于小样本缺陷检测,YOLO-SBN模型在平均准确率(mAP)方面提高了4.1%;在新类缺陷样本规模数量为50的小样本情况下,改进后的检测模型对新类数据适应性最强。由此可见,该YOLO-SBN模型在提高检测精度和提升模型泛化能力方面具有一定优势。 展开更多
关键词 小样本目标检测 表面缺陷 元学习 特征网络 归一化注意力模块 平均准确率 双向特征金字塔网络(BiFPN)
在线阅读 下载PDF
上一页 1 2 234 下一页 到第
使用帮助 返回顶部