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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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Modulated-ISRJ rejection using online dictionary learning for synthetic aperture radar imagery 被引量:1
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作者 WEI Shaopeng ZHANG Lei +1 位作者 LU Jingyue LIU Hongwei 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期316-329,共14页
In electromagnetic countermeasures circumstances,synthetic aperture radar(SAR)imagery usually suffers from severe quality degradation from modulated interrupt sampling repeater jamming(MISRJ),which usually owes consid... In electromagnetic countermeasures circumstances,synthetic aperture radar(SAR)imagery usually suffers from severe quality degradation from modulated interrupt sampling repeater jamming(MISRJ),which usually owes considerable coherence with the SAR transmission waveform together with periodical modulation patterns.This paper develops an MISRJ suppression algorithm for SAR imagery with online dictionary learning.In the algorithm,the jamming modulation temporal properties are exploited with extracting and sorting MISRJ slices using fast-time autocorrelation.Online dictionary learning is followed to separate real signals from jamming slices.Under the learned representation,time-varying MISRJs are suppressed effectively.Both simulated and real-measured SAR data are also used to confirm advantages in suppressing time-varying MISRJs over traditional methods. 展开更多
关键词 synthetic aperture radar(SAR) modulated interrupt sampling jamming(MISRJ) online dictionary learning
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Computational intelligence interception guidance law using online off-policy integral reinforcement learning
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作者 WANG Qi LIAO Zhizhong 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期1042-1052,共11页
Missile interception problem can be regarded as a two-person zero-sum differential games problem,which depends on the solution of Hamilton-Jacobi-Isaacs(HJI)equa-tion.It has been proved impossible to obtain a closed-f... Missile interception problem can be regarded as a two-person zero-sum differential games problem,which depends on the solution of Hamilton-Jacobi-Isaacs(HJI)equa-tion.It has been proved impossible to obtain a closed-form solu-tion due to the nonlinearity of HJI equation,and many iterative algorithms are proposed to solve the HJI equation.Simultane-ous policy updating algorithm(SPUA)is an effective algorithm for solving HJI equation,but it is an on-policy integral reinforce-ment learning(IRL).For online implementation of SPUA,the dis-turbance signals need to be adjustable,which is unrealistic.In this paper,an off-policy IRL algorithm based on SPUA is pro-posed without making use of any knowledge of the systems dynamics.Then,a neural-network based online adaptive critic implementation scheme of the off-policy IRL algorithm is pre-sented.Based on the online off-policy IRL method,a computa-tional intelligence interception guidance(CIIG)law is developed for intercepting high-maneuvering target.As a model-free method,intercepting targets can be achieved through measur-ing system data online.The effectiveness of the CIIG is verified through two missile and target engagement scenarios. 展开更多
关键词 two-person zero-sum differential games Hamilton–Jacobi–Isaacs(HJI)equation off-policy integral reinforcement learning(IRL) online learning computational intelligence inter-ception guidance(CIIG)law
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Air combat target maneuver trajectory prediction based on robust regularized Volterra series and adaptive ensemble online transfer learning 被引量:2
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作者 Xi Zhi-fei Kou Ying-xin +4 位作者 Li Zhan-wu Lv Yue Xu An Li You Li Shuang-qing 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第2期187-206,共20页
Target maneuver trajectory prediction is an important prerequisite for air combat situation awareness and maneuver decision-making.However,how to use a large amount of trajectory data generated by air combat confronta... Target maneuver trajectory prediction is an important prerequisite for air combat situation awareness and maneuver decision-making.However,how to use a large amount of trajectory data generated by air combat confrontation training to achieve real-time and accurate prediction of target maneuver trajectory is an urgent problem to be solved.To solve this problem,in this paper,a hybrid algorithm based on transfer learning,online learning,ensemble learning,regularization technology,target maneuvering segmentation point recognition algorithm,and Volterra series,abbreviated as AERTrOS-Volterra is proposed.Firstly,the model makes full use of a large number of trajectory sample data generated by air combat confrontation training,and constructs a Tr-Volterra algorithm framework suitable for air combat target maneuver trajectory prediction,which realizes the extraction of effective information from the historical trajectory data.Secondly,in order to improve the real-time online prediction accuracy and robustness of the prediction model in complex electromagnetic environments,on the basis of the TrVolterra algorithm framework,a robust regularized online Sequential Volterra prediction model is proposed by integrating online learning method,regularization technology and inverse weighting calculation method based on the priori error.Finally,inspired by the preferable performance of models ensemble,ensemble learning scheme is also incorporated into our proposed algorithm,which adaptively updates the ensemble prediction model according to the performance of the model on real-time samples and the recognition results of target maneuvering segmentation points,including the adaptation of model weights;adaptation of parameters;and dynamic inclusion and removal of models.Compared with many existing time series prediction methods,the newly proposed target maneuver trajectory prediction algorithm can fully mine the prior knowledge contained in the historical data to assist the current prediction.The rationality and effectiveness of the proposed algorithm are verified by simulation on three sets of chaotic time series data sets and a set of real target maneuver trajectory data sets. 展开更多
关键词 Maneuver trajectory prediction Volterra series Transfer learning online learning Ensemble learning Robust regularization
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Social Presence and Implications for Designing Online Learning Communities 被引量:1
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作者 Charlotte N.(Lani)Gunawardena 《开放教育研究》 CSSCI 2005年第5期54-60,共7页
With the rapid global proliferation of the Internet and telecommunication networks, online education, one form of distance education is currently becoming the fastest growing trend of domestic and international educat... With the rapid global proliferation of the Internet and telecommunication networks, online education, one form of distance education is currently becoming the fastest growing trend of domestic and international education. A major challenge to designing online learning is the development of appropriate means to facilitate the social environment that is critical for higher order learning in many disciplines. In many online learning designs, the majority of resources are channeled to web interface design and technology, while little or no resources are devoted to facilitating the teaching and learning process, the negotiation of meaning and the validation of knowledge among peers and instructors that depends on a conducive socio-cultural environment and adequate learner support. 展开更多
关键词 现代远程教育 第四届 教育技术 国际论坛 主题报告 2005年 南昌市
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A Model of Teaching and Learning Online in Asian Context 被引量:1
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作者 Md Kabirul Islam 《开放教育研究》 CSSCI 2005年第6期63-67,共5页
Online teaching and learning practices in Asian universities are different from that in western universities. Western universities give emphasis on student-student interaction for learning. Online courses offered by m... Online teaching and learning practices in Asian universities are different from that in western universities. Western universities give emphasis on student-student interaction for learning. Online courses offered by most Asian universities are a kind of mixed mode that comprised simultaneous face-to-face tutorials and online interaction facility. In this situation most students use the online facility to collect resources and to contact their teachers. The quantity of student-student interaction was sporadic in many courses. So research is needed to improve the situation and create an environment for students where they can learn what peer group interaction is and practice it. This paper has presented a model of teaching and learning online for Asian universities. Possible barriers in teaching and learning situations in Asia and students' abilities have been considered to develop the model. 展开更多
关键词 亚洲 在线学习 开放教育 现代远程教育 教学模式
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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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Developing Online Learning Communities:Five Factors to Consider in a Journey without Maps
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作者 Susan E.Kerstein 《开放教育研究》 CSSCI 2005年第1期55-57,共3页
Through a three year qualitative research study, the researcher examed how faculty in higher education are thinking about, constructing and developing interactive learning enviorments, and identified five fundeamental... Through a three year qualitative research study, the researcher examed how faculty in higher education are thinking about, constructing and developing interactive learning enviorments, and identified five fundeamental foutors to consider in developing effective online learning communities, Which may help to negotiate the new enviorment for students and faculty. 展开更多
关键词 在线教育 在线学习团体 交互式学习 学习方式
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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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浅析E-Learning与数字图书馆的关系 被引量:11
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作者 王灿荣 袁闯 《现代情报》 北大核心 2006年第5期88-89,共2页
本文简单地阐述了E-Learning的定义和特征,并重点分析了作为一种全新的学习方式的E-Learning与数字图书馆之间的关系。
关键词 E-learning在线学习 数字化学习 数字图书馆
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基于Online-RBFNN的航空发动机动态模型研究 被引量:1
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作者 王志浩 魏民祥 +2 位作者 叶志锋 吴昊 杨佳伟 《重庆理工大学学报(自然科学)》 CAS 北大核心 2022年第4期203-212,共10页
为解决航空发动机在出现性能退化时模型精度下降的问题,提出了一种基于在线径向基函数神经网络(online radial basis function neural network,Online-RBFNN)的航空发动机动态模型。采用连续K均值(K-Means)算法和FTRL(follow the regula... 为解决航空发动机在出现性能退化时模型精度下降的问题,提出了一种基于在线径向基函数神经网络(online radial basis function neural network,Online-RBFNN)的航空发动机动态模型。采用连续K均值(K-Means)算法和FTRL(follow the regularized leader)在线学习算法,对典型RBFNN进行改进,实现在线学习功能。以某型涡扇发动机正常退化数据为原始样本,建立低压涡轮机(low pressure turbine,LPT)出口总温度动态模型,并与其他多种算法建立的模型进行对比,动态模型的平均绝对误差、均方根误差和校正决定系数分别为0.59、1.7和0.9978;将所建立的动态模型在同型号但不同飞行包线区域、不同退化形式的发动机运行数据上进行测试,模型输出结果的误差可分别控制在[-9,8]K和[-10,9]K范围内。研究结果表明,基于Online-RBFNN的动态模型能有效避免模型精度下降的问题,且具有良好的自适应能力。 展开更多
关键词 航空发动机 online-RBFNN 在线学习 动态模型
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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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A Study on Online Interaction between Tutor and Students 被引量:1
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作者 Sri Sediyaningsih Aminudin Zuhairi 《开放教育研究》 CSSCI 北大核心 2011年第3期68-73,共6页
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刮板输送机断链智能监测技术研究 被引量:2
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作者 李灵锋 张洁 +2 位作者 陈茁 查天任 尹瑞 《工矿自动化》 北大核心 2025年第3期63-69,77,共8页
针对现有基于AI算法的煤矿井下刮板输送机断链监测技术在线学习能力低、检测精度差、稳定性低、复杂场景适应性和可靠性差等问题,通过在极限学习机(ELM)中增加增量式在线训练,设计了可实现离线样本和实时在线样本训练的在线贯序极限学习... 针对现有基于AI算法的煤矿井下刮板输送机断链监测技术在线学习能力低、检测精度差、稳定性低、复杂场景适应性和可靠性差等问题,通过在极限学习机(ELM)中增加增量式在线训练,设计了可实现离线样本和实时在线样本训练的在线贯序极限学习机(OSELM)网络,进而提出了基于OSELM的刮板输送机断链智能监测技术。将经过大量煤矿井下刮板输送机链条监控图像(离线样本)训练的OSELM网络算法写入AI摄像仪,将AI摄像仪安装于刮板输送机机尾,实时感知刮板输送机链条运行状态并进行在线学习,由AI摄像仪输出控制决策,并通过刮板输送机集中控制系统平台实时显示识别结果。井下工业性试验结果表明,OSELM网络具有较高的自主学习能力、较强的泛化性和鲁棒性,对刮板输送机断链识别的平均精度均值、准确率和精确率分别为98.6%,99.3%,91.7%,检测速度达205.6帧/s,整体效果优于深度神经网络融合网络、RT-DETR、YOLOv5、YOLOv8、ELM等模型,实现了刮板输送机链条状态的精准、实时检测。 展开更多
关键词 刮板输送机 链条状态识别 断链监测 AI摄像仪 在线贯序极限学习机网络
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大学生在线学习数字韧性框架构建与培育路径 被引量:1
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作者 吴鹏泽 狄璇 李冰 《现代远程教育研究》 北大核心 2025年第3期40-51,共12页
在线学习已成为大学生重要的学习方式之一,然而伴随人工智能技术的快速发展,在线学习过程中面临的信息超载、技术风险、伦理冲突等问题日益凸显,这就要求学生应当具备一定的数字韧性来积极应对这些挑战。在线学习数字韧性作为一种特定... 在线学习已成为大学生重要的学习方式之一,然而伴随人工智能技术的快速发展,在线学习过程中面临的信息超载、技术风险、伦理冲突等问题日益凸显,这就要求学生应当具备一定的数字韧性来积极应对这些挑战。在线学习数字韧性作为一种特定情境下的数字韧性,强调学生克服技术障碍、识别潜在风险,并通过情绪调节和人际支持等策略持续达成学习目标的能力。基于对已有韧性理论、数字韧性框架的观照,面向大学生的在线学习数字韧性框架包含风险理解力、问题解决力、逆境恢复力、自我提升力4个一级维度及相应的12个二级维度。该框架经过两阶段实证检验,结果表明其具有较好的信效度,可用于持续监测和有效提升学生的数字韧性水平,助力学生更好地适应数字化学习环境。针对当前大学生群体的数字韧性普遍存在能力结构性失衡、知行脱节、发展非持续等典型问题,为了更好地培养其在线学习数字韧性,应注重从三方面着手:一是建立技术风险联防体系,形成数字素养教育闭环;二是同步加强技术干预与韧性训练,促进心理与行为协同发展;三是分群体定制韧性培养方案,构建持续提升学生数字韧性的支持体系。 展开更多
关键词 在线学习 数字韧性 框架构建 培育路径 大学生
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面向雷达目标识别的一种在线迁移学习框架
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作者 杨予昊 孙晶明 +2 位作者 张强 晏媛 王众 《现代雷达》 北大核心 2025年第5期16-20,共5页
可靠、高效、精准的目标识别性能需求,与完备的目标数据库构建困难之间的矛盾,要求雷达目标识别系统具备动态学习能力,动态实现数据、模型的更新与识别能力的跃升。而样本自标注、模型自更新等功能的实现是达到这一目标的前提条件。针... 可靠、高效、精准的目标识别性能需求,与完备的目标数据库构建困难之间的矛盾,要求雷达目标识别系统具备动态学习能力,动态实现数据、模型的更新与识别能力的跃升。而样本自标注、模型自更新等功能的实现是达到这一目标的前提条件。针对雷达目标识别在实际应用中的性能自提升需求,通过借鉴在线学习与迁移学习的思想,提出一种在线迁移学习框架,通过结合在线学习和迁移学习技术,采用闭环结构,通过样本标注和模型微调,实现模型的自我迭代优化,可自动完成样本标注、模型更新等任务。基于仿真数据的实验结果表明,所提框架可显著提升雷达目标识别的准确性,具有流程简单、部署快捷的优点,具有较强的工程实用性。 展开更多
关键词 雷达目标识别 样本自标注 模型自更新 在线学习 迁移学习
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基于EMO-GAN的恶意URL检测框架
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作者 耿海军 蔚超 +3 位作者 胡治国 郭小英 池浩田 杨静 《计算机应用研究》 北大核心 2025年第2期582-591,共10页
随着万维网的广泛应用和网络威胁的日益严峻,统一资源定位符(uniform resource locator,URL)的安全性成为了网络安全领域的研究热点,如何有效检测并防范恶意URL已经成为了业内非常关注的问题。针对恶意URL检测中存在的数据获取困难、特... 随着万维网的广泛应用和网络威胁的日益严峻,统一资源定位符(uniform resource locator,URL)的安全性成为了网络安全领域的研究热点,如何有效检测并防范恶意URL已经成为了业内非常关注的问题。针对恶意URL检测中存在的数据获取困难、特征表示不足以及模型概念漂移挑战,提出了一种基于EMO-GAN的恶意URL检测框架(EMO-GAN-based malicious URL detection framework,EMO-GANUDF)。该框架通过结合极度随机树(extremely randomized trees,ET)和边缘生成对抗网络(margin generative adversarial network,MarginGAN)进行半监督学习,有效解决了数据获取困难问题。在特征提取上,该框架提出了一种综合统计、字符和词汇特征的特征表示方法,实现了URL的高效特征表示。此外,为了应对模型概念漂移问题,该框架提出了一种支持在线学习(online learning)的分类器,增强了模型拓展性和适应性。在多个数据集和不同检测方法上进行对比实验,所提方法在Malicious URLs公开数据集上达到了99%的准确率和84%的F 1分数,较其他检测方法取得了更好的效果,证明了其有效性及优越性。 展开更多
关键词 恶意URL 极度随机树 半监督学习 生成对抗网络 在线学习
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面向深度调峰和智能发电的炉膛温度场在线监测及预测综述
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作者 方顺利 晋中华 +11 位作者 杨云 李翔 任世鹏 马帅 姚斌 王浩帆 张中晖 梅晟东 刘凯 陈新建 娄春 邹莹 《热力发电》 北大核心 2025年第4期13-23,共11页
在火电机组参与深度调峰时,炉膛温度场的实时获取有助于电站锅炉控制和研究炉内燃烧过程,在智能发电的推进下,机器学习为实时获得炉膛温度场提供了重要手段。总结了声学法、吸收光谱层析成像法以及热辐射成像法这3种最常用的炉膛温度场... 在火电机组参与深度调峰时,炉膛温度场的实时获取有助于电站锅炉控制和研究炉内燃烧过程,在智能发电的推进下,机器学习为实时获得炉膛温度场提供了重要手段。总结了声学法、吸收光谱层析成像法以及热辐射成像法这3种最常用的炉膛温度场在线监测技术的原理及应用,以及在锅炉炉膛测温应用中存在的优势及缺点。之后详细阐述了耦合机器学习与CFD的预测方法的原理,说明该方法在恶劣炉内环境中受到的影响较小,综述了该方法在燃烧火焰结构及参数和炉膛温度场的应用研究,表明了该方法应用于炉膛温度场的可行性,并可准确地预测获得炉膛温度场。最后对炉膛温度场在线监测技术和耦合机器学习与CFD的预测方法的未来发展趋势进行了分析,以便在电站智能化建设进程下,为实时快速获得更准确的炉膛温度场提供思路。 展开更多
关键词 电站锅炉 炉膛温度场 在线监测 机器学习 预测
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一种基于直接反馈对齐的精确脉冲时间学习规则
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作者 宁黎苗 王自铭 +2 位作者 林志诚 彭舰 唐华锦 《计算机科学》 北大核心 2025年第3期260-267,共8页
由于脉冲神经元和突触复杂的时空动力学特性,训练脉冲神经网络比较困难,目前尚不存在公认的核心训练算法与技术。为此,提出一种基于直接反馈对齐(DFA)的精确脉冲时间(PREST-DFA)学习规则。受脉冲分层误差再分配(SLAYER)学习算法的启发,P... 由于脉冲神经元和突触复杂的时空动力学特性,训练脉冲神经网络比较困难,目前尚不存在公认的核心训练算法与技术。为此,提出一种基于直接反馈对齐(DFA)的精确脉冲时间(PREST-DFA)学习规则。受脉冲分层误差再分配(SLAYER)学习算法的启发,PREST-DFA使用基于脉冲卷积差的误差信号,输出层通过迭代方式计算出误差值,利用基于DFA的误差传输机制,将误差广播至隐藏层神经元,最后实现突触权值更新。仿真实验表明,实现了时间驱动的PREST-DFA学习算法具有精确脉冲时间学习能力。根据文献查询结果,这是首次验证基于DFA机制的学习算法可以在深层网络中控制脉冲的精确发放时间,说明DFA机制可以应用于基于脉冲时间的算法设计。另外还进行了学习性能和训练速度的比较,实验结果表明PREST-DFA能在较低的推理延迟下实现良好的学习性能,与采用相同学习规则使用反向传播训练的学习算法相比,能够加快训练速度。 展开更多
关键词 脉冲神经网络 直接反馈对齐 学习规则 精确脉冲时间 在线学习
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