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Detection of geohazards caused by human disturbance activities based on convolutional neural networks
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作者 ZHANG Heng ZHANG Diandian +1 位作者 YUAN Da LIU Tao 《水利水电技术(中英文)》 北大核心 2025年第S1期731-738,共8页
Human disturbance activities is one of the main reasons for inducing geohazards.Ecological impact assessment metrics of roads are inconsistent criteria and multiple.From the perspective of visual observation,the envir... Human disturbance activities is one of the main reasons for inducing geohazards.Ecological impact assessment metrics of roads are inconsistent criteria and multiple.From the perspective of visual observation,the environment damage can be shown through detecting the uncovered area of vegetation in the images along road.To realize this,an end-to-end environment damage detection model based on convolutional neural network is proposed.A 50-layer residual network is used to extract feature map.The initial parameters are optimized by transfer learning.An example is shown by this method.The dataset including cliff and landslide damage are collected by us along road in Shennongjia national forest park.Results show 0.4703 average precision(AP)rating for cliff damage and 0.4809 average precision(AP)rating for landslide damage.Compared with YOLOv3,our model shows a better accuracy in cliff and landslide detection although a certain amount of speed is sacrificed. 展开更多
关键词 convolutional neural network DETECTION environment damage CLIFF LANDSLIDE
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High-resolution reconstruction of the ablative RT instability flowfield via convolutional neural networks
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作者 Xia Zhiyang Kuang Yuanyuan +1 位作者 Lu Yan Yang Ming 《强激光与粒子束》 CAS CSCD 北大核心 2024年第12期42-49,共8页
High-resolution flow field data has important applications in meteorology,aerospace engineering,high-energy physics and other fields.Experiments and numerical simulations are two main ways to obtain high-resolution fl... High-resolution flow field data has important applications in meteorology,aerospace engineering,high-energy physics and other fields.Experiments and numerical simulations are two main ways to obtain high-resolution flow field data,while the high experiment cost and computing resources for simulation hinder the specificanalysis of flow field evolution.With the development of deep learning technology,convolutional neural networks areused to achieve high-resolution reconstruction of the flow field.In this paper,an ordinary convolutional neuralnetwork and a multi-time-path convolutional neural network are established for the ablative Rayleigh-Taylorinstability.These two methods can reconstruct the high-resolution flow field in just a few seconds,and further greatlyenrich the application of high-resolution reconstruction technology in fluid instability.Compared with the ordinaryconvolutional neural network,the multi-time-path convolutional neural network model has smaller error and canrestore more details of the flow field.The influence of low-resolution flow field data obtained by the two poolingmethods on the convolutional neural networks model is also discussed. 展开更多
关键词 convolutional neural networks ablative Rayleigh-Taylor instability high-resolutionreconstruction multi-time-path pooling
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Convolutional neural networks for time series classification 被引量:52
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作者 Bendong Zhao Huanzhang Lu +2 位作者 Shangfeng Chen Junliang Liu Dongya Wu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第1期162-169,共8页
Time series classification is an important task in time series data mining, and has attracted great interests and tremendous efforts during last decades. However, it remains a challenging problem due to the nature of ... Time series classification is an important task in time series data mining, and has attracted great interests and tremendous efforts during last decades. However, it remains a challenging problem due to the nature of time series data: high dimensionality, large in data size and updating continuously. The deep learning techniques are explored to improve the performance of traditional feature-based approaches. Specifically, a novel convolutional neural network (CNN) framework is proposed for time series classification. Different from other feature-based classification approaches, CNN can discover and extract the suitable internal structure to generate deep features of the input time series automatically by using convolution and pooling operations. Two groups of experiments are conducted on simulated data sets and eight groups of experiments are conducted on real-world data sets from different application domains. The final experimental results show that the proposed method outperforms state-of-the-art methods for time series classification in terms of the classification accuracy and noise tolerance. © 1990-2011 Beijing Institute of Aerospace Information. 展开更多
关键词 convolutION Data mining neural networks Time series Virtual reality
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Discrimination of mining microseismic events and blasts using convolutional neural networks and original waveform 被引量:24
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作者 DONG Long-jun TANG Zheng +2 位作者 LI Xi-bing CHEN Yong-chao XUE Jin-chun 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第10期3078-3089,共12页
Microseismic monitoring system is one of the effective methods for deep mining geo-stress monitoring.The principle of microseismic monitoring system is to analyze the mechanical parameters contained in microseismic ev... Microseismic monitoring system is one of the effective methods for deep mining geo-stress monitoring.The principle of microseismic monitoring system is to analyze the mechanical parameters contained in microseismic events for providing accurate information of rockmass.The accurate identification of microseismic events and blasts determines the timeliness and accuracy of early warning of microseismic monitoring technology.An image identification model based on Convolutional Neural Network(CNN)is established in this paper for the seismic waveforms of microseismic events and blasts.Firstly,the training set,test set,and validation set are collected,which are composed of 5250,1500,and 750 seismic waveforms of microseismic events and blasts,respectively.The classified data sets are preprocessed and input into the constructed CNN in CPU mode for training.Results show that the accuracies of microseismic events and blasts are 99.46%and 99.33%in the test set,respectively.The accuracies of microseismic events and blasts are 100%and 98.13%in the validation set,respectively.The proposed method gives superior performance when compared with existed methods.The accuracies of models using logistic regression and artificial neural network(ANN)based on the same data set are 54.43%and 67.9%in the test set,respectively.Then,the ROC curves of the three models are obtained and compared,which show that the CNN gives an absolute advantage in this classification model when the original seismic waveform are used in training the model.It not only decreases the influence of individual differences in experience,but also removes the errors induced by source and waveform parameters.It is proved that the established discriminant method improves the efficiency and accuracy of microseismic data processing for monitoring rock instability and seismicity. 展开更多
关键词 microseismic monitoring waveform classification microseismic events BLASTS convolutional neural network
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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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Automatic Calcified Plaques Detection in the OCT Pullbacks Using Convolutional Neural Networks 被引量:2
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作者 Chunliu He Yifan Yin +2 位作者 Jiaqiu Wang Biao Xu Zhiyong Li 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期109-110,共2页
Background Coronary artery calcification is a well-known marker of atherosclerotic plaque burden.High-resolution intravascular optical coherence tomography(OCT)imaging has shown the potential to characterize the detai... Background Coronary artery calcification is a well-known marker of atherosclerotic plaque burden.High-resolution intravascular optical coherence tomography(OCT)imaging has shown the potential to characterize the details of coronary calcification in vivo.In routine clinical practice,it is a time-consuming and laborious task for clinicians to review the over 250 images in a single pullback.Besides,the imbalance label distribution within the entire pullbacks is another problem,which could lead to the failure of the classifier model.Given the success of deep learning methods with other imaging modalities,a thorough understanding of calcified plaque detection using Convolutional Neural Networks(CNNs)within pullbacks for future clinical decision was required.Methods All 33 IVOCT clinical pullbacks of 33 patients were taken from Affiliated Drum Tower Hospital,Nanjing University between December 2017 and December 2018.For ground-truth annotation,three trained experts determined the type of plaque that was present in a B-Scan.The experts assigned the labels'no calcified plaque','calcified plaque'for each OCT image.All experts were provided the all images for labeling.The final label was determined based on consensus between the experts,different opinions on the plaque type were resolved by asking the experts for a repetition of their evaluation.Before the implement of algorithm,all OCT images was resized to a resolution of 300×300,which matched the range used with standard architectures in the natural image domain.In the study,we randomly selected 26 pullbacks for training,the remaining data were testing.While,imbalance label distribution within entire pullbacks was great challenge for various CNNs architecture.In order to resolve the problem,we designed the following experiment.First,we fine-tuned twenty different CNNs architecture,including customize CNN architectures and pretrained CNN architectures.Considering the nature of OCT images,customize CNN architectures were designed that the layers were fewer than 25 layers.Then,three with good performance were selected and further deep fine-tuned to train three different models.The difference of CNNs was mainly in the model architecture,such as depth-based residual networks,width-based inception networks.Finally,the three CNN models were used to majority voting,the predicted labels were from the most voting.Areas under the receiver operating characteristic curve(ROC AUC)were used as the evaluation metric for the imbalance label distribution.Results The imbalance label distribution within pullbacks affected both convergence during the training phase and generalization of a CNN model.Different labels of OCT images could be classified with excellent performance by fine tuning parameters of CNN architectures.Overall,we find that our final result performed best with an accuracy of 90%of'calcified plaque'class,which the numbers were less than'no calcified plaque'class in one pullback.Conclusions The obtained results showed that the method is fast and effective to classify calcific plaques with imbalance label distribution in each pullback.The results suggest that the proposed method could be facilitating our understanding of coronary artery calcification in the process of atherosclerosis andhelping guide complex interventional strategies in coronary arteries with superficial calcification. 展开更多
关键词 CALCIFIED PLAQUE INTRAVASCULAR optical coherence tomography deep learning IMBALANCE LABEL distribution convolutional neural networks
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Deep convolutional neural network for meteorology target detection in airborne weather radar images 被引量:3
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作者 YU Chaopeng XIONG Wei +1 位作者 LI Xiaoqing DONG Lei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第5期1147-1157,共11页
Considering the problem that the scattering echo images of airborne Doppler weather radar are often reduced by ground clutters,the accuracy and confidence of meteorology target detection are reduced.In this paper,a de... Considering the problem that the scattering echo images of airborne Doppler weather radar are often reduced by ground clutters,the accuracy and confidence of meteorology target detection are reduced.In this paper,a deep convolutional neural network(DCNN)is proposed for meteorology target detection and ground clutter suppression with a large collection of airborne weather radar images as network input.For each weather radar image,the corresponding digital elevation model(DEM)image is extracted on basis of the radar antenna scan-ning parameters and plane position,and is further fed to the net-work as a supplement for ground clutter suppression.The fea-tures of actual meteorology targets are learned in each bottle-neck module of the proposed network and convolved into deeper iterations in the forward propagation process.Then the network parameters are updated by the back propagation itera-tion of the training error.Experimental results on the real mea-sured images show that our proposed DCNN outperforms the counterparts in terms of six evaluation factors.Meanwhile,the network outputs are in good agreement with the expected mete-orology detection results(labels).It is demonstrated that the pro-posed network would have a promising meteorology observa-tion application with minimal effort on network variables or parameter changes. 展开更多
关键词 meteorology target detection ground clutter sup-pression weather radar images convolutional neural network(CNN)
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Real-time object segmentation based on convolutional neural network with saliency optimization for picking 被引量:1
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作者 CHEN Jinbo WANG Zhiheng LI Hengyu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第6期1300-1307,共8页
This paper concerns the problem of object segmentation in real-time for picking system. A region proposal method inspired by human glance based on the convolutional neural network is proposed to select promising regio... This paper concerns the problem of object segmentation in real-time for picking system. A region proposal method inspired by human glance based on the convolutional neural network is proposed to select promising regions, allowing more processing is reserved only for these regions. The speed of object segmentation is significantly improved by the region proposal method.By the combination of the region proposal method based on the convolutional neural network and superpixel method, the category and location information can be used to segment objects and image redundancy is significantly reduced. The processing time is reduced considerably by this to achieve the real time. Experiments show that the proposed method can segment the interested target object in real time on an ordinary laptop. 展开更多
关键词 convolutional neural network object detection object segmentation superpixel saliency optimization
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Uplink NOMA signal transmission with convolutional neural networks approach 被引量:3
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作者 LIN Chuan CHANG Qing LI Xianxu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第5期890-898,共9页
Non-orthogonal multiple access(NOMA), featuring high spectrum efficiency, massive connectivity and low latency, holds immense potential to be a novel multi-access technique in fifth-generation(5G) communication. Succe... Non-orthogonal multiple access(NOMA), featuring high spectrum efficiency, massive connectivity and low latency, holds immense potential to be a novel multi-access technique in fifth-generation(5G) communication. Successive interference cancellation(SIC) is proved to be an effective method to detect the NOMA signal by ordering the power of received signals and then decoding them. However, the error accumulation effect referred to as error propagation is an inevitable problem. In this paper,we propose a convolutional neural networks(CNNs) approach to restore the desired signal impaired by the multiple input multiple output(MIMO) channel. Especially in the uplink NOMA scenario,the proposed method can decode multiple users' information in a cluster instantaneously without any traditional communication signal processing steps. Simulation experiments are conducted in the Rayleigh channel and the results demonstrate that the error performance of the proposed learning system outperforms that of the classic SIC detection. Consequently, deep learning has disruptive potential to replace the conventional signal detection method. 展开更多
关键词 non-orthogonal multiple access(NOMA) deep learning(DL) convolutional neural networks(CNNs) signal detection
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基于1DCNN特征提取和RF分类的滚动轴承故障诊断
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作者 张豪 刘其洪 +1 位作者 李伟光 李漾 《中国测试》 北大核心 2025年第4期137-143,共7页
针对深度学习技术在滚动轴承故障诊断识别中依赖于大量测量数据,相对较少的数据可能会导致过度拟合并降低模型的稳定性等问题,提出一种一维卷积神经网络(1DCNN)和随机森林(RF)相结合的轴承故障诊断模型。将原始时域信号输入搭建的1DCNN... 针对深度学习技术在滚动轴承故障诊断识别中依赖于大量测量数据,相对较少的数据可能会导致过度拟合并降低模型的稳定性等问题,提出一种一维卷积神经网络(1DCNN)和随机森林(RF)相结合的轴承故障诊断模型。将原始时域信号输入搭建的1DCNN网络中,提取原始数据特征向量,对特征向量进行t-SNE降维可视化,验证1DCNN特征提取的有效性。将特征向量输入随机森林实现故障状态识别,解决小样本的滚动轴承故障分类问题。在CWRU数据集和Paderborn数据集上进行实验,针对不同类型、不同损伤程度的轴承,得到分类结果准确率分别达到99.69%和99.16%。与传统的神经网络和机器学习分类模型相比,1DCNN-RF模型具有更高的诊断准确率,可验证所提模型的泛化性和有效性。 展开更多
关键词 滚动轴承 故障诊断 一维卷积神经网络 随机森林
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基于高光谱成像和MSC1DCNN的大豆种子热损伤无损检测
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作者 谭克竹 孙伟奇 +3 位作者 卓宗慧 李凯诺 张喜海 闫超 《光谱学与光谱分析》 北大核心 2025年第10期2897-2905,共9页
大豆种子由于存储和运输不当,容易产生热损伤问题。热损伤会影响种子的种质质量和发芽率,因此准确地检测热损伤大豆种子对于提高种子品质和农业生产具有重要意义。本文提出了一种基于高光谱成像和多尺度跨通道一维卷积神经网络(MSC1DCNN... 大豆种子由于存储和运输不当,容易产生热损伤问题。热损伤会影响种子的种质质量和发芽率,因此准确地检测热损伤大豆种子对于提高种子品质和农业生产具有重要意义。本文提出了一种基于高光谱成像和多尺度跨通道一维卷积神经网络(MSC1DCNN)的大豆种子热损伤无损检测方法。首先,通过高光谱成像系统获取大豆种子在400~1000 nm波段的光谱数据,并对比分析不同热损伤大豆种子(正常、轻微热损伤、严重热损伤)的光谱曲线特点。发现在420~500 nm蓝光区域和750~1000 nm近红外区域,光谱反射率随着热损伤程度的加深逐渐增大。这些变化为后续的热损伤检测提供了有效的光谱特征依据。其次,采用MSC1DCNN模型进行分类,该模型在测试集上的准确率、召回率和F1分数均达到99.07%,优于支持向量机(SVC)(F1分数为88.32%)、k-近邻算法(KNN)(F1分数为84.39%)及一维卷积神经网络(1D CNN)(F1分数为92.90%)。特别地,MSC1DCNN模型在鉴别轻微热损伤与正常大豆种子时误判率为1.39%,显著低于SVC(12.04%)、KNN(15.74%)和1D CNN(9.72%)模型。最后,还通过发芽试验验证了热损伤对大豆种子发芽率的影响。实验结果表明,热损伤显著降低了大豆种子的发芽率,进一步证实了热损伤对大豆生长的潜在危害。综上所述,本研究提出的MSC1DCNN模型为热损伤大豆种子的无损检测提供了一种有效解决方案,对种质质量检测和自动化筛选工作提供了新的思路。 展开更多
关键词 大豆种子 高光谱 热损伤 一维卷积
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基于Attention-1DCNN-CE的加密流量分类方法
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作者 耿海军 董赟 +3 位作者 胡治国 池浩田 杨静 尹霞 《计算机应用》 北大核心 2025年第3期872-882,共11页
针对传统加密流量识别方法存在多分类准确率低、泛化性不强以及易侵犯隐私等问题,提出一种结合注意力机制(Attention)与一维卷积神经网络(1DCNN)的多分类深度学习模型——Attention-1DCNN-CE。该模型包含3个核心部分:1)数据集预处理阶段... 针对传统加密流量识别方法存在多分类准确率低、泛化性不强以及易侵犯隐私等问题,提出一种结合注意力机制(Attention)与一维卷积神经网络(1DCNN)的多分类深度学习模型——Attention-1DCNN-CE。该模型包含3个核心部分:1)数据集预处理阶段,保留原始数据流中数据包间的空间关系,并根据样本分布构建成本敏感矩阵;2)在初步提取加密流量特征的基础上,利用Attention和1DCNN模型深入挖掘并压缩流量的全局与局部特征;3)针对数据不平衡这一挑战,通过结合成本敏感矩阵与交叉熵(CE)损失函数,显著提升少数类别样本的分类精度,进而优化模型的整体性能。实验结果表明,在BOT-IOT和TON-IOT数据集上该模型的整体识别准确率高达97%以上;并且该模型在公共数据集ISCX-VPN和USTC-TFC上表现优异,在不需要预训练的前提下,达到了与ET-BERT(Encrypted Traffic BERT)相近的性能;相较于PERT(Payload Encoding Representation from Transformer),该模型在ISCX-VPN数据集的应用类型检测中的F1分数提升了29.9个百分点。以上验证了该模型的有效性,为加密流量识别和恶意流量检测提供了解决方案。 展开更多
关键词 网络安全 加密流量 注意力机制 一维卷积神经网络 数据不平衡 成本敏感矩阵
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波长注意力1DCNN近红外光谱定量分析算法研究
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作者 陈蓓 蒋思远 郑恩让 《光谱学与光谱分析》 北大核心 2025年第6期1598-1604,共7页
近红外光谱(NIRS)技术因其快速、无损和高效的特点,广泛应用于石油、纺织、食品、制药等领域。然而传统的分析方法在处理变量多、冗余大的光谱数据时,往往存在特征提取困难和建模精度不高等问题。因此提出一种适用于近红外光谱且无需变... 近红外光谱(NIRS)技术因其快速、无损和高效的特点,广泛应用于石油、纺织、食品、制药等领域。然而传统的分析方法在处理变量多、冗余大的光谱数据时,往往存在特征提取困难和建模精度不高等问题。因此提出一种适用于近红外光谱且无需变量筛选的一维波长注意力卷积神经网络(WA-1DCNN)定量建模方法,该建模方法结构简单、通用性强、准确率高。该研究引入波长注意力机制,通过赋予不同波长数据不同的权重,增强模型对重要波长特征的捕捉能力,从而提高定量分析的准确性和鲁棒性。为了验证所提出方法的可行性,采用了公开的4种近红外光谱数据集,将所提出的算法与加入波长筛选偏最小二乘法(PLS)、支持向量回归(SVR)、极限学习机(ELM)三种传统建模方法和一维卷积神经网络(1DCNN)建模方法进行了对比,并通过模型性能指标均方根误差(RMSE)和决定系数(R^(2))对模型性能评估。结果表明没有使用波长筛选算法的WA-1DCNN建模方法性能指标均优于加入波长筛选算法的传统建模方法和1DCNN建模方法。其中在655药片数据集中测试集决定系数为0.9563,相比于1DCNN和加入波长筛选的PLS、SVR、ELM提升了4.34%、12.56%、18.42%、11.59%;在310药片数据集中测试集决定系数为0.9574,相比于1DCNN和加入波长筛选的PLS、SVR、ELM、1DCNN提升了2.72%、8.28%、7.27%、1.17%;在玉米水分和蛋白质数据集中测试集决定系数分别为0.9803和0.9685,相比于1DCNN和加入波长筛选的PLS、SVR、ELM提升了6.24%、1.48%、1.75%、6.08%和5.81%、1.85%、1.58%、2.96%;在小麦蛋白质数据集中测试集决定系数为0.9600,相比于DCNN和加入波长筛选的PLS、SVR、ELM提升了8.67%、5.79%、7.94%、0.56%。为了验证WA-1DCNN模型结构的最佳性,在4种近红外光谱数据集上进行了改变WA-1DCNN模型结构的消融实验。研究结果表明:基于波长注意力卷积神经网络是一种结构简单、通用性强、准确率高的光谱定量分析方法,该方法对于近红外光谱定量分析具有促进作用。 展开更多
关键词 近红外光谱 定量分析 波长注意力机制 一维卷积神经网络
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基于MS1DCNN-BOA-SVM的智能液压系统故障诊断方法
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作者 闫锋 肖成军 +2 位作者 孙一伟 孙有朝 谭忠睿 《机床与液压》 北大核心 2025年第8期174-181,共8页
针对液压系统故障特征提取困难、诊断准确率低等问题,提出一种基于多尺度一维卷积神经网络(MS1DCNN)和贝叶斯搜索优化支持向量机(SVM)的智能故障诊断模型。将多个传感器信号合并为单一输入信号;通过多尺度卷积处理提取关键故障特征,构... 针对液压系统故障特征提取困难、诊断准确率低等问题,提出一种基于多尺度一维卷积神经网络(MS1DCNN)和贝叶斯搜索优化支持向量机(SVM)的智能故障诊断模型。将多个传感器信号合并为单一输入信号;通过多尺度卷积处理提取关键故障特征,构建特征向量;然后,利用贝叶斯搜索优化SVM进行分类识别,构建故障诊断模型;最后,对模型进行训练。结果表明:该模型对柱塞泵和蓄能器的故障诊断准确率分别为99.63%、99.17%;与MS1DCNN、1DCNN、SVM模型相比,该模型在液压系统故障诊断方面具有高准确率、高可靠性和强泛化能力的优势。 展开更多
关键词 液压系统 多尺度卷积神经网络 支持向量机 贝叶斯搜索优化 故障诊断
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基于MPDCNN的强噪声环境下船舶电力推进器齿轮箱故障诊断方法
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作者 尚前明 蒋婉莹 +2 位作者 周毅 王正强 孙钰波 《中国舰船研究》 北大核心 2025年第2期30-38,共9页
[目的]针对旋转机械在实际工作中因噪声干扰而导致的故障诊断性能下降问题,为提高振动信号的故障特征提取质量和故障诊断能力,提出基于Mel-frequency倒谱系数(MFCC)的并行双通道卷积神经网络(PDCNN)故障诊断方法。[方法]利用MFCC提取含... [目的]针对旋转机械在实际工作中因噪声干扰而导致的故障诊断性能下降问题,为提高振动信号的故障特征提取质量和故障诊断能力,提出基于Mel-frequency倒谱系数(MFCC)的并行双通道卷积神经网络(PDCNN)故障诊断方法。[方法]利用MFCC提取含噪声的振动信号特征,同时设计一种新型并行双通道卷积神经网络结构,并利用该网络进一步挖掘数据的全局特征及更深层次的微小特征,从而提高该方法在强噪声环境下的诊断性能。[结果]不同噪声环境下的实验评估结果表明,该方法在强噪声环境下的故障诊断精度高于98%,其抗噪性能和诊断性能均明显优于其他传统方法。[结论]研究成果可为强噪声环境下的齿轮箱故障诊断提供参考。 展开更多
关键词 船舶电力推进 齿轮箱 故障分析 故障诊断 特征提取 梅尔频率倒谱系数 卷积神经网络
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基于MC2DCNN-LSTM模型的齿轮箱全故障分类识别模型
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作者 陈蓉 王磊 《机电工程》 北大核心 2025年第2期287-297,共11页
针对轧机齿轮箱结构复杂、故障信号识别困难、故障部位分类不清等难题,提出了一种基于多通道二维卷积神经网络(MC2DCNN)与长短期记忆神经网络(LSTM)特征融合的故障诊断方法。首先,设计了一种三通道混合编码的二维样本结构,以达到故障识... 针对轧机齿轮箱结构复杂、故障信号识别困难、故障部位分类不清等难题,提出了一种基于多通道二维卷积神经网络(MC2DCNN)与长短期记忆神经网络(LSTM)特征融合的故障诊断方法。首先,设计了一种三通道混合编码的二维样本结构,以达到故障识别与分类目的,对齿轮箱典型故障进行了自适应分类;其次,该模型将齿轮箱的垂直、水平和轴向三个方向的振动信号融合构造输入样本,结合了二维卷积神经网络与长短时记忆神经网络的优势,设计了与之对应的二维卷积神经网络结构,其相较于传统的单通道信号包含了更多的状态信息;最后,分析了轧制过程数据和已有实验数据,对齿轮故障和齿轮箱全故障进行了特征识别和分类,验证了该模型的准确率。研究结果表明:模型对齿轮箱齿面磨损、齿根裂纹、断齿以及齿面点蚀等典型故障识别的平均准确率达到95.9%,最高准确率为98.6%;相较于单通道信号,多通道信号混合编码方式构造的分类样本极大地提升了神经网络分类的准确性,解调出了更丰富的故障信息。根据轧制过程中的运行数据和实验台数据,验证了该智能诊断方法较传统方法在分类和识别准确率上更具优势,为该方法的工程应用提供了理论基础。 展开更多
关键词 高精度轧机齿轮箱 智能故障诊断 多通道二维卷积神经网络 长短期记忆神经网络 数据分类
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基于FDTRP-ALDCNN的小样本轴承故障诊断方法
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作者 王娜 刘佳林 王子从 《铁道科学与工程学报》 北大核心 2025年第9期4271-4283,共13页
针对滚动轴承在小样本条件下诊断精度低的问题,提出一种基于频域无阈值递归图与自适应线性可变卷积神经网络(frequency domain thresholdless recurrence plot-adaptive linear deformable convolutional neural network,FDTRP-ALDCNN)... 针对滚动轴承在小样本条件下诊断精度低的问题,提出一种基于频域无阈值递归图与自适应线性可变卷积神经网络(frequency domain thresholdless recurrence plot-adaptive linear deformable convolutional neural network,FDTRP-ALDCNN)的滚动轴承故障诊断方法。首先,使用快速傅里叶变换(fast fourier transform,FFT)将一维时域信号转为频域信号,并与无阈值递归图(thresholdless recurrence plot,TRP)相结合,以有效构建初始特征,提高模型输入质量;其次,采用线性可变卷积核(linear deformable convolutional kernel,LDConv)替换卷积神经网络中方形卷积核,从而能够根据采样数据的分布来调整卷积核形状,准确获取空间信息中的关键特征,提高小样本数据的利用率;再次,设计自适应交叉熵(adaptive cross entropy,ACE)损失函数,根据样本分类损失自适应调整分类器对难分与易分样本的拟合程度,增强难分样本损失在整体分类损失中的显著性,进一步提高小样本下的模型诊断精度;最后,采用CWRU滚动轴承数据集对所提方法进行3组仿真验证。对比仿真的结果表明,所提模型在不同小样本数量下均有较高的诊断准确率,最高可达到99.82%。而对2组不平衡数据集的泛化性分析可知,本模型的诊断准确率分别达到98.56%与99.3%,泛化能力优于其他模型,且具有良好的稳定性。并通过消融实验验证了FFT、LDConv与ACE损失函数对提高故障诊断精度的有效性。综上所述,所提方法能够有效诊断出小样本轴承故障,具有较高的实际应用价值。 展开更多
关键词 故障诊断 小样本 无阈值递归图 线性可变卷积核 卷积神经网络 交叉熵损失函数
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基于1DCNN和PLSDA酸枣仁真伪高光谱图像鉴别中的关键特征分析 被引量:2
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作者 赵昕 石玉娜 +5 位作者 刘怡彤 姜洪喆 褚璇 赵志磊 王宝军 陈晗 《光谱学与光谱分析》 北大核心 2025年第3期869-877,共9页
酸枣仁因其养心益肝的功效,是安神助眠类保健品和中药制剂的重要原料。目前市售酸枣仁掺假现象严重,极大损害了消费者利益,扰乱了市场秩序。传统人工检测或基于实验室的高效液相色谱方法存在效率低,推广难的问题。本研究基于卷积神经网... 酸枣仁因其养心益肝的功效,是安神助眠类保健品和中药制剂的重要原料。目前市售酸枣仁掺假现象严重,极大损害了消费者利益,扰乱了市场秩序。传统人工检测或基于实验室的高效液相色谱方法存在效率低,推广难的问题。本研究基于卷积神经网络和偏最小二乘判别提出了一种高光谱成像酸枣仁真伪鉴别方法,并对两类模型中的关键光谱特征进行了讨论研究,为后续多光谱系统和便携式仪器开发提供借鉴。提取酸枣仁及其常见伪品(理枣仁、兵豆和枳椇子)高光谱图像(400~1000 nm)中所有单籽粒的平均光谱。基于平均光谱分别建立偏最小二乘判别分析(PLSDA)模型和一维卷积神经网络(1DCNN)模型。PLSDA建模前采用竞争性自适应重加权算法(CARS)挑选特征波长。在1DCNN模型中添加了自定义波长选择层,并对卷积层和全连接层输出结果应用t分布随机邻域嵌入(t-SNE)进行可视化分析。为了与CARS-PLSDA模型进行有效对比,构建了基于五个波长的5W-1DCNN模型。结果表明CARS-PLSDA和1DCNN模型都能获得理想的预测效果,校正集和预测集分类正确率均在99%以上。对比CARS与自定义层挑选的特征波长,670、721和850 nm附近的波长在两种模型中均具有重要作用。研究结果为酸枣仁真伪快速鉴别的多光谱和便携式检测设备提供参考。 展开更多
关键词 高光谱成像 一维卷积神经网络 t分布随机邻域嵌入 偏最小二乘法判别分析
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Automatic modulation recognition of radiation source signals based on two-dimensional data matrix and improved residual neural network
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作者 Guanghua Yi Xinhong Hao +3 位作者 Xiaopeng Yan Jian Dai Yangtian Liu Yanwen Han 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期364-373,共10页
Automatic modulation recognition(AMR)of radiation source signals is a research focus in the field of cognitive radio.However,the AMR of radiation source signals at low SNRs still faces a great challenge.Therefore,the ... Automatic modulation recognition(AMR)of radiation source signals is a research focus in the field of cognitive radio.However,the AMR of radiation source signals at low SNRs still faces a great challenge.Therefore,the AMR method of radiation source signals based on two-dimensional data matrix and improved residual neural network is proposed in this paper.First,the time series of the radiation source signals are reconstructed into two-dimensional data matrix,which greatly simplifies the signal preprocessing process.Second,the depthwise convolution and large-size convolutional kernels based residual neural network(DLRNet)is proposed to improve the feature extraction capability of the AMR model.Finally,the model performs feature extraction and classification on the two-dimensional data matrix to obtain the recognition vector that represents the signal modulation type.Theoretical analysis and simulation results show that the AMR method based on two-dimensional data matrix and improved residual network can significantly improve the accuracy of the AMR method.The recognition accuracy of the proposed method maintains a high level greater than 90% even at -14 dB SNR. 展开更多
关键词 Automatic modulation recognition Radiation source signals Two-dimensional data matrix Residual neural network Depthwise convolution
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基于3DCNN融合TFT的储粮结露风险预测研究
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作者 李欣泽 乔星瀚 +4 位作者 王文越 乌云山丹 吴文福 郭鸿鹏 卢延辉 《农业机械学报》 北大核心 2025年第7期549-557,共9页
针对当前储粮结露风险预测主要依赖简单粮温监测和经验判断、缺乏准确预测工具的问题,本文提出了一种结合三维卷积神经网络(3DCNN)和时间融合变换器(TFT)的储粮结露风险预测方法。该方法通过3DCNN提取粮堆内部温度场的空间特征,结合TFT... 针对当前储粮结露风险预测主要依赖简单粮温监测和经验判断、缺乏准确预测工具的问题,本文提出了一种结合三维卷积神经网络(3DCNN)和时间融合变换器(TFT)的储粮结露风险预测方法。该方法通过3DCNN提取粮堆内部温度场的空间特征,结合TFT处理时间序列数据,基于历史气象数据和未来气象预报数据,实现了粮堆温度场的高精度预测,并利用预测结果与未来7 d气象预报数据进行结露风险预判。研究采用新疆塔城地区8个粮仓的实测数据进行了模型训练和验证,获得了精确的粮温预测模型。在测试集上进行了模型性能对比实验,结果显示,3 DCNN-TFT模型在粮堆温度场预测中的平均绝对误差(MAE)为0.16℃,均方根误差(RMSE)为0.18℃,显著优于其他预测模型。最后通过实仓实验验证了模型泛化能力,实验结果显示,3DCNN-TFT模型具有较高的预测精度,平均MAE为0.16℃,RMSE为0.19℃。同时,模型成功预测了结露风险并提前发出预警。本文方法显著提高了粮堆温度场预测精度,准确预测了结露风险,为储粮粮情监管与预测系统开发提供了有力支持。 展开更多
关键词 储粮 结露风险 温度场预测 3D卷积神经网络 时间融合变换器
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