期刊文献+
共找到402篇文章
< 1 2 21 >
每页显示 20 50 100
Dynamic behavior recognition in aerial deployment of multi-segmented foldable-wing drones using variational autoencoders
1
作者 Yilin DOU Zhou ZHOU Rui WANG 《Chinese Journal of Aeronautics》 2025年第6期143-165,共23页
The aerial deployment method enables Unmanned Aerial Vehicles(UAVs)to be directly positioned at the required altitude for their mission.This method typically employs folding technology to improve loading efficiency,wi... The aerial deployment method enables Unmanned Aerial Vehicles(UAVs)to be directly positioned at the required altitude for their mission.This method typically employs folding technology to improve loading efficiency,with applications such as the gravity-only aerial deployment of high-aspect-ratio solar-powered UAVs,and aerial takeoff of fixed-wing drones in Mars research.However,the significant morphological changes during deployment are accompanied by strong nonlinear dynamic aerodynamic forces,which result in multiple degrees of freedom and an unstable character.This hinders the description and analysis of unknown dynamic behaviors,further leading to difficulties in the design of deployment strategies and flight control.To address this issue,this paper proposes an analysis method for dynamic behaviors during aerial deployment based on the Variational Autoencoder(VAE).Focusing on the gravity-only deployment problem of highaspect-ratio foldable-wing UAVs,the method encodes the multi-degree-of-freedom unstable motion signals into a low-dimensional feature space through a data-driven approach.By clustering in the feature space,this paper identifies and studies several dynamic behaviors during aerial deployment.The research presented in this paper offers a new method and perspective for feature extraction and analysis of complex and difficult-to-describe extreme flight dynamics,guiding the research on aerial deployment drones design and control strategies. 展开更多
关键词 Dynamic behavior recognition Aerial deployment technology variational autoencoder Pattern recognition Multi-rigid-bodydynamics
原文传递
Spatially Constrained Variational Autoencoder for Geochemical Data Denoising and Uncertainty Quantification
2
作者 Dazheng Huang Renguang Zuo +1 位作者 Jian Wang Raimon Tolosana-Delgado 《Journal of Earth Science》 2025年第5期2317-2336,共20页
Geochemical survey data are essential across Earth Science disciplines but are often affected by noise,which can obscure important geological signals and compromise subsequent prediction and interpretation.Quantifying... Geochemical survey data are essential across Earth Science disciplines but are often affected by noise,which can obscure important geological signals and compromise subsequent prediction and interpretation.Quantifying prediction uncertainty is hence crucial for robust geoscientific decision-making.This study proposes a novel deep learning framework,the Spatially Constrained Variational Autoencoder(SC-VAE),for denoising geochemical survey data with integrated uncertainty quantification.The SC-VAE incorporates spatial regularization,which enforces spatial coherence by modeling inter-sample relationships directly within the latent space.The performance of the SC-VAE was systematically evaluated against a standard Variational Autoencoder(VAE)using geochemical data from the gold polymetallic district in the northwestern part of Sichuan Province,China.Both models were optimized using Bayesian optimization,with objective functions specifically designed to maintain essential geostatistical characteristics.Evaluation metrics include variogram analysis,quantitative measures of spatial interpolation accuracy,visual assessment of denoised maps,and statistical analysis of data distributions,as well as decomposition of uncertainties.Results show that the SC-VAE achieves superior noise suppression and better preservation of spatial structure compared to the standard VAE,as demonstrated by a significant reduction in the variogram nugget effect and an increased partial sill.The SC-VAE produces denoised maps with clearer anomaly delineation and more regularized data distributions,effectively mitigating outliers and reducing kurtosis.Additionally,it delivers improved interpolation accuracy and spatially explicit uncertainty estimates,facilitating more reliable and interpretable assessments of prediction confidence.The SC-VAE framework thus provides a robust,geostatistically informed solution for enhancing the quality and interpretability of geochemical data,with broad applicability in mineral exploration,environmental geochemistry,and other Earth Science domains. 展开更多
关键词 geochemical data denoising spatially constrained variational autoencoder GEOSTATISTICS bayesian optimization uncertainty analysis GEOCHEMISTRY
原文传递
Wavelet Transform-Based Bayesian Inference Learning with Conditional Variational Autoencoder for Mitigating Injection Attack in 6G Edge Network
3
作者 Binu Sudhakaran Pillai Raghavendra Kulkarni +1 位作者 Venkata Satya Suresh kumar Kondeti Surendran Rajendran 《Computer Modeling in Engineering & Sciences》 2025年第10期1141-1166,共26页
Future 6G communications will open up opportunities for innovative applications,including Cyber-Physical Systems,edge computing,supporting Industry 5.0,and digital agriculture.While automation is creating efficiencies... Future 6G communications will open up opportunities for innovative applications,including Cyber-Physical Systems,edge computing,supporting Industry 5.0,and digital agriculture.While automation is creating efficiencies,it can also create new cyber threats,such as vulnerabilities in trust and malicious node injection.Denialof-Service(DoS)attacks can stop many forms of operations by overwhelming networks and systems with data noise.Current anomaly detection methods require extensive software changes and only detect static threats.Data collection is important for being accurate,but it is often a slow,tedious,and sometimes inefficient process.This paper proposes a new wavelet transformassisted Bayesian deep learning based probabilistic(WT-BDLP)approach tomitigate malicious data injection attacks in 6G edge networks.The proposed approach combines outlier detection based on a Bayesian learning conditional variational autoencoder(Bay-LCVariAE)and traffic pattern analysis based on continuous wavelet transform(CWT).The Bay-LCVariAE framework allows for probabilistic modelling of generative features to facilitate capturing how features of interest change over time,spatially,and for recognition of anomalies.Similarly,CWT allows emphasizing the multi-resolution spectral analysis and permits temporally relevant frequency pattern recognition.Experimental testing showed that the flexibility of the Bayesian probabilistic framework offers a vast improvement in anomaly detection accuracy over existing methods,with a maximum accuracy of 98.21%recognizing anomalies. 展开更多
关键词 Bayesian inference learning automaton convolutional wavelet transform conditional variational autoencoder malicious data injection attack edge environment 6G communication
在线阅读 下载PDF
Semi-Supervised Segmentation Framework for Quantitative Analysis of Material Microstructure Images
4
作者 Yingli Liu Weiyong Tang +2 位作者 Xiao Yang Jiancheng Yin Haihe Zhou 《Computers, Materials & Continua》 2026年第4期596-611,共16页
Quantitative analysis of aluminum-silicon(Al-Si)alloy microstructure is crucial for evaluating and controlling alloy performance.Conventional analysis methods rely on manual segmentation,which is inefficient and subje... Quantitative analysis of aluminum-silicon(Al-Si)alloy microstructure is crucial for evaluating and controlling alloy performance.Conventional analysis methods rely on manual segmentation,which is inefficient and subjective,while fully supervised deep learning approaches require extensive and expensive pixel-level annotated data.Furthermore,existing semi-supervised methods still face challenges in handling the adhesion of adjacent primary silicon particles and effectively utilizing consistency in unlabeled data.To address these issues,this paper proposes a novel semi-supervised framework for Al-Si alloy microstructure image segmentation.First,we introduce a Rotational Uncertainty Correction Strategy(RUCS).This strategy employs multi-angle rotational perturbations andMonte Carlo sampling to assess prediction consistency,generating a pixel-wise confidence weight map.By integrating this map into the loss function,the model dynamically focuses on high-confidence regions,thereby improving generalization ability while reducing manual annotation pressure.Second,we design a Boundary EnhancementModule(BEM)to strengthen boundary feature extraction through erosion difference and multi-scale dilated convolutions.This module guides the model to focus on the boundary regions of adjacent particles,effectively resolving particle adhesion and improving segmentation accuracy.Systematic experiments were conducted on the Aluminum-Silicon Alloy Microstructure Dataset(ASAD).Results indicate that the proposed method performs exceptionally well with scarce labeled data.Specifically,using only 5%labeled data,our method improves the Jaccard index and Adjusted Rand Index(ARI)by 2.84 and 1.57 percentage points,respectively,and reduces the Variation of Information(VI)by 8.65 compared to stateof-the-art semi-supervised models,approaching the performance levels of 10%labeled data.These results demonstrate that the proposed method significantly enhances the accuracy and robustness of quantitative microstructure analysis while reducing annotation costs. 展开更多
关键词 Microstructure alloy semi-supervised segmentation boundary enhancement variation of information
在线阅读 下载PDF
Multi-Modal Domain Adaptation Variational Autoencoder for EEG-Based Emotion Recognition 被引量:6
5
作者 Yixin Wang Shuang Qiu +3 位作者 Dan Li Changde Du Bao-Liang Lu Huiguang He 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第9期1612-1626,共15页
Traditional electroencephalograph(EEG)-based emotion recognition requires a large number of calibration samples to build a model for a specific subject,which restricts the application of the affective brain computer i... Traditional electroencephalograph(EEG)-based emotion recognition requires a large number of calibration samples to build a model for a specific subject,which restricts the application of the affective brain computer interface(BCI)in practice.We attempt to use the multi-modal data from the past session to realize emotion recognition in the case of a small amount of calibration samples.To solve this problem,we propose a multimodal domain adaptive variational autoencoder(MMDA-VAE)method,which learns shared cross-domain latent representations of the multi-modal data.Our method builds a multi-modal variational autoencoder(MVAE)to project the data of multiple modalities into a common space.Through adversarial learning and cycle-consistency regularization,our method can reduce the distribution difference of each domain on the shared latent representation layer and realize the transfer of knowledge.Extensive experiments are conducted on two public datasets,SEED and SEED-IV,and the results show the superiority of our proposed method.Our work can effectively improve the performance of emotion recognition with a small amount of labelled multi-modal data. 展开更多
关键词 Cycle-consistency domain adaptation electroencephalograph(EEG) multi modality variational autoencoder
在线阅读 下载PDF
An efficient stock market prediction model using hybrid feature reduction method based on variational autoencoders and recursive feature elimination 被引量:5
6
作者 Hakan Gunduz 《Financial Innovation》 2021年第1期585-608,共24页
In this study,the hourly directions of eight banking stocks in Borsa Istanbul were predicted using linear-based,deep-learning(LSTM)and ensemble learning(Light-GBM)models.These models were trained with four different f... In this study,the hourly directions of eight banking stocks in Borsa Istanbul were predicted using linear-based,deep-learning(LSTM)and ensemble learning(Light-GBM)models.These models were trained with four different feature sets and their performances were evaluated in terms of accuracy and F-measure metrics.While the first experiments directly used the own stock features as the model inputs,the second experiments utilized reduced stock features through Variational AutoEncoders(VAE).In the last experiments,in order to grasp the effects of the other banking stocks on individual stock performance,the features belonging to other stocks were also given as inputs to our models.While combining other stock features was done for both own(named as allstock_own)and VAE-reduced(named as allstock_VAE)stock features,the expanded dimensions of the feature sets were reduced by Recursive Feature Elimination.As the highest success rate increased up to 0.685 with allstock_own and LSTM with attention model,the combination of allstock_VAE and LSTM with the attention model obtained an accuracy rate of 0.675.Although the classification results achieved with both feature types was close,allstock_VAE achieved these results using nearly 16.67%less features compared to allstock_own.When all experimental results were examined,it was found out that the models trained with allstock_own and allstock_VAE achieved higher accuracy rates than those using individual stock features.It was also concluded that the results obtained with the VAE-reduced stock features were similar to those obtained by own stock features. 展开更多
关键词 Stock market prediction variational autoencoder Recursive feature elimination Long-short term memory Borsa Istanbul LightGBM
在线阅读 下载PDF
Generate Faces Using Ladder Variational Autoencoder with Maximum Mean Discrepancy (MMD) 被引量:1
7
作者 Haoji Xu 《Intelligent Information Management》 2018年第4期108-113,共6页
Generative Models have been shown to be extremely useful in learning features from unlabeled data. In particular, variational autoencoders are capable of modeling highly complex natural distributions such as images, w... Generative Models have been shown to be extremely useful in learning features from unlabeled data. In particular, variational autoencoders are capable of modeling highly complex natural distributions such as images, while extracting natural and human-understandable features without labels. In this paper we combine two highly useful classes of models, variational ladder autoencoders, and MMD variational autoencoders, to model face images. In particular, we show that we can disentangle highly meaningful and interpretable features. Furthermore, we are able to perform arithmetic operations on faces and modify faces to add or remove high level features. 展开更多
关键词 GENERATIVE Models LADDER variational autoencoders FACIAL Recognition
暂未订购
Enhancing the Effectiveness of Trimethylchlorosilane Purification Process Monitoring with Variational Autoencoder 被引量:1
8
作者 Jinfu Wang Shunyi Zhao +1 位作者 Fei Liu Zhenyi Ma 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第8期531-552,共22页
In modern industry,process monitoring plays a significant role in improving the quality of process conduct.With the higher dimensional of the industrial data,the monitoring methods based on the latent variables have b... In modern industry,process monitoring plays a significant role in improving the quality of process conduct.With the higher dimensional of the industrial data,the monitoring methods based on the latent variables have been widely applied in order to decrease the wasting of the industrial database.Nevertheless,these latent variables do not usually follow the Gaussian distribution and thus perform unsuitable when applying some statistics indices,especially the T^(2) on them.Variational AutoEncoders(VAE),an unsupervised deep learning algorithm using the hierarchy study method,has the ability to make the latent variables follow the Gaussian distribution.The partial least squares(PLS)are used to obtain the information between the dependent variables and independent variables.In this paper,we will integrate these two methods and make a comparison with other methods.The superiority of this proposed method will be verified by the simulation and the Trimethylchlorosilane purification process in terms of the multivariate control charts. 展开更多
关键词 Process monitoring variational autoencoders partial least square multivariate control chart
在线阅读 下载PDF
Facial landmark disentangled network with variational autoencoder
9
作者 LIANG Sen ZHOU Zhi-ze +3 位作者 GUO Yu-dong GAO Xuan ZHANG Ju-yong BAO Hu-jun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2022年第2期290-305,共16页
Learning disentangled representation of data is a key problem in deep learning.Specifically,disentangling 2D facial landmarks into different factors(e.g.,identity and expression)is widely used in the applications of f... Learning disentangled representation of data is a key problem in deep learning.Specifically,disentangling 2D facial landmarks into different factors(e.g.,identity and expression)is widely used in the applications of face reconstruction,face reenactment and talking head et al..However,due to the sparsity of landmarks and the lack of accurate labels for the factors,it is hard to learn the disentangled representation of landmarks.To address these problem,we propose a simple and effective model named FLD-VAE to disentangle arbitrary facial landmarks into identity and expression latent representations,which is based on a Variational Autoencoder framework.Besides,we propose three invariant loss functions in both latent and data levels to constrain the invariance of representations during training stage.Moreover,we implement an identity preservation loss to further enhance the representation ability of identity factor.To the best of our knowledge,this is the first work to end-to-end disentangle identity and expression factors simultaneously from one single facial landmark. 展开更多
关键词 disentanglement representation deep learning facial landmarks variational autoencoder
在线阅读 下载PDF
Variational quantum semi-supervised classifier based on label propagation
10
作者 侯艳艳 李剑 +1 位作者 陈秀波 叶崇强 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期279-289,共11页
Label propagation is an essential semi-supervised learning method based on graphs,which has a broad spectrum of applications in pattern recognition and data mining.This paper proposes a quantum semi-supervised classif... Label propagation is an essential semi-supervised learning method based on graphs,which has a broad spectrum of applications in pattern recognition and data mining.This paper proposes a quantum semi-supervised classifier based on label propagation.Considering the difficulty of graph construction,we develop a variational quantum label propagation(VQLP)method.In this method,a locally parameterized quantum circuit is created to reduce the parameters required in the optimization.Furthermore,we design a quantum semi-supervised binary classifier based on hybrid Bell and Z bases measurement,which has a shallower circuit depth and is more suitable for implementation on near-term quantum devices.We demonstrate the performance of the quantum semi-supervised classifier on the Iris data set,and the simulation results show that the quantum semi-supervised classifier has higher classification accuracy than the swap test classifier.This work opens a new path to quantum machine learning based on graphs. 展开更多
关键词 semi-supervised learning variational quantum algorithm parameterized quantum circuit
原文传递
Semi-supervised gear fault diagnosis using raw vibration signal based on deep learning 被引量:18
11
作者 Xueyi LI Jialin LI +1 位作者 Yongzhi QU David HE 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第2期418-426,共9页
In aerospace industry,gears are the most common parts of a mechanical transmission system.Gear pitting faults could cause the transmission system to crash and give rise to safety disaster.It is always a challenging pr... In aerospace industry,gears are the most common parts of a mechanical transmission system.Gear pitting faults could cause the transmission system to crash and give rise to safety disaster.It is always a challenging problem to diagnose the gear pitting condition directly through the raw signal of vibration.In this paper,a novel method named augmented deep sparse autoencoder(ADSAE)is proposed.The method can be used to diagnose the gear pitting fault with relatively few raw vibration signal data.This method is mainly based on the theory of pitting fault diagnosis and creatively combines with both data augmentation ideology and the deep sparse autoencoder algorithm for the fault diagnosis of gear wear.The effectiveness of the proposed method is validated by experiments of six types of gear pitting conditions.The results show that the ADSAE method can effectively increase the network generalization ability and robustness with very high accuracy.This method can effectively diagnose different gear pitting conditions and show the obvious trend according to the severity of gear wear faults.The results obtained by the ADSAE method proposed in this paper are compared with those obtained by other common deep learning methods.This paper provides an important insight into the field of gear fault diagnosis based on deep learning and has a potential practical application value. 展开更多
关键词 Deep LEARNING GEAR PITTING diagnosis GEAR teeth RAW vibration signal semi-supervised LEARNING SPARSE autoencoder
原文传递
Semi-supervised Ladder Networks for Speech Emotion Recognition 被引量:9
12
作者 Jian-Hua Tao Jian Huang +2 位作者 Ya Li Zheng Lian Ming-Yue Niu 《International Journal of Automation and computing》 EI CSCD 2019年第4期437-448,共12页
As a major component of speech signal processing, speech emotion recognition has become increasingly essential to understanding human communication. Benefitting from deep learning, many researchers have proposed vario... As a major component of speech signal processing, speech emotion recognition has become increasingly essential to understanding human communication. Benefitting from deep learning, many researchers have proposed various unsupervised models to extract effective emotional features and supervised models to train emotion recognition systems. In this paper, we utilize semi-supervised ladder networks for speech emotion recognition. The model is trained by minimizing the supervised loss and auxiliary unsupervised cost function. The addition of the unsupervised auxiliary task provides powerful discriminative representations of the input features, and is also regarded as the regularization of the emotional supervised task. We also compare the ladder network with other classical autoencoder structures. The experiments were conducted on the interactive emotional dyadic motion capture (IEMOCAP) database, and the results reveal that the proposed methods achieve superior performance with a small number of labelled data and achieves better performance than other methods. 展开更多
关键词 SPEECH EMOTION RECOGNITION the LADDER network semi-supervised learning autoencoder REGULARIZATION
原文传递
Network Intrusion Detection in Internet of Blended Environment Using Ensemble of Heterogeneous Autoencoders(E-HAE)
13
作者 Lelisa Adeba Jilcha Deuk-Hun Kim +1 位作者 Julian Jang-Jaccard Jin Kwak 《Computer Systems Science & Engineering》 SCIE EI 2023年第9期3261-3284,共24页
Contemporary attackers,mainly motivated by financial gain,consistently devise sophisticated penetration techniques to access important information or data.The growing use of Internet of Things(IoT)technology in the co... Contemporary attackers,mainly motivated by financial gain,consistently devise sophisticated penetration techniques to access important information or data.The growing use of Internet of Things(IoT)technology in the contemporary convergence environment to connect to corporate networks and cloud-based applications only worsens this situation,as it facilitates multiple new attack vectors to emerge effortlessly.As such,existing intrusion detection systems suffer from performance degradation mainly because of insufficient considerations and poorly modeled detection systems.To address this problem,we designed a blended threat detection approach,considering the possible impact and dimensionality of new attack surfaces due to the aforementioned convergence.We collectively refer to the convergence of different technology sectors as the internet of blended environment.The proposed approach encompasses an ensemble of heterogeneous probabilistic autoencoders that leverage the corresponding advantages of a convolutional variational autoencoder and long short-term memory variational autoencoder.An extensive experimental analysis conducted on the TON_IoT dataset demonstrated 96.02%detection accuracy.Furthermore,performance of the proposed approach was compared with various single model(autoencoder)-based network intrusion detection approaches:autoencoder,variational autoencoder,convolutional variational autoencoder,and long short-term memory variational autoencoder.The proposed model outperformed all compared models,demonstrating F1-score improvements of 4.99%,2.25%,1.92%,and 3.69%,respectively. 展开更多
关键词 Network intrusion detection anomaly detection TON_IoT dataset smart grid smart city smart factory digital healthcare autoencoder variational autoencoder LSTM convolutional variational autoencoder ensemble learning
在线阅读 下载PDF
基于多尺度信息的生成式人体姿态估计
14
作者 陈俊芬 冯武山 +1 位作者 郝旭阳 谢博鋆 《计算机工程与应用》 北大核心 2026年第3期265-276,共12页
针对人体姿态估计中遮挡带来的缺乏图像低级特征指导和预测姿势与人体生理结构的不一致性问题,提出了一种新颖的生成式人体姿态估计方法(generative human pose estimation,GenPose)。该模型使用多尺度信息融合和条件生成模块解决了严... 针对人体姿态估计中遮挡带来的缺乏图像低级特征指导和预测姿势与人体生理结构的不一致性问题,提出了一种新颖的生成式人体姿态估计方法(generative human pose estimation,GenPose)。该模型使用多尺度信息融合和条件生成模块解决了严重遮挡问题。多尺度模块从尺度和通道上细粒度融合图像特征,能捕捉到更多肢体细节,从而推理出遮挡关键点的特征信息。条件生成模块通过建模遮挡场景与姿态间的对应关系,根据标记编码器特征动态调整生成姿态,在保证可见点准确率的同时,在一定程度上减少了遮挡对非遮挡的干扰,提升了对遮挡姿态的生成效果。在公开的COCO和MPII数据集上,同以往方法相比,有了更好的结果,同时在CrowdPose、OCHuman以及SyncOCC数据集上验证了泛化能力。该模型在一定程度上能够解决严重遮挡下的姿态估计问题,提高了预测姿态的合理性,取得了更加优异的效果。 展开更多
关键词 人体姿态估计 不可见关键点 严重遮挡 注意力机制 变分编码器
在线阅读 下载PDF
基于Diff-Cascade的低资源命名实体识别方法
15
作者 邱云飞 董丽波 张文文 《计算机科学与探索》 北大核心 2026年第2期533-545,共13页
在低资源命名实体识别(NER)任务中,目前许多基于迁移学习的方法虽然能够缓解数据稀缺问题,但往往会导致句子中部分正确信息的遗漏或识别错误,从而影响模型在低资源环境中的效果。针对此问题,提出了一种基于多模块协同的NER模型Diff-Casc... 在低资源命名实体识别(NER)任务中,目前许多基于迁移学习的方法虽然能够缓解数据稀缺问题,但往往会导致句子中部分正确信息的遗漏或识别错误,从而影响模型在低资源环境中的效果。针对此问题,提出了一种基于多模块协同的NER模型Diff-Cascade-NER。利用变分自编码器(VAE)在潜在空间中学习数据表示,并生成多样化的样本;将上下文信息、句法分析和VAE重构数据作为条件输入到条件编码器(CE)进行编码;将编码后的数据传递给级联扩散模型(CDM),通过多阶段的去噪和生成过程产生高质量样本;通过对抗学习阶段(AL)优化生成样本的质量和多样性。实验结果表明,对比现有模型,Diff-Cascade-NER在8个低资源数据集上表现优越,特别是在BC2GM和WNUT-16数据集上,F1值分别达到85.44%和56.38%,验证了各模块协同作用在低资源NER任务中的有效性。 展开更多
关键词 低资源命名实体识别 变分自编码器 条件编码器 级联扩散模型 对抗学习
在线阅读 下载PDF
区域感知与VAE量化隐藏的卫星图像压缩算法
16
作者 张荔哲 周诠 +2 位作者 肖化超 郑小松 呼延烺 《中国空间科学技术(中英文)》 北大核心 2026年第1期185-197,共13页
为了解决基于神经网络的卫星图像压缩中对复杂特征区域细节丢失的问题,提出一种结合区域感知、变分自编码网络(VAE)量化层隐藏信息的新型压缩算法。优先考虑关键区域质量,同时保持整体压缩率并支持隐蔽数据嵌入。算法首先基于YOLO模型... 为了解决基于神经网络的卫星图像压缩中对复杂特征区域细节丢失的问题,提出一种结合区域感知、变分自编码网络(VAE)量化层隐藏信息的新型压缩算法。优先考虑关键区域质量,同时保持整体压缩率并支持隐蔽数据嵌入。算法首先基于YOLO模型进行重点区域感知,自动识别并提取图像中包含复杂纹理和关键信息的区域。结合ResNet VAE模型将图像映射至潜在空间,在量化空间特征的过程中,将重点区域信息隐藏在背景压缩码流中后再进行熵编码。采用差异化压缩策略,对背景进行激进压缩,对关键区域进行轻度压缩,从而优化整体压缩效率。实验证明,与传统和主流深度学习压缩算法相比,通过潜在功能块重构、空间特征量化与无冗余信息隐藏策略,在平均25倍的压缩比下,全幅图像的PSNR较国际先进压缩算法提升了3~5 dB,平均值为35.27 dB。重点区域的PSNR达41.15 dB,SSIM为0.992,较基线算法提升7.55 dB,有效弥补了其他方法在特征细节保留上的缺陷。综合多组卫星图像验证结果显示,算法在不增加码流的情况下提升了压缩效果,并提供了可靠的数据隐蔽与安全传输功能,在高分辨率卫星图像的压缩与敏感区域数据保护方面表现出优越性能,为相关场景数据的高效存储和安全应用提供了一种新颖的解决方案。 展开更多
关键词 卫星图像压缩 区域感知 变分自编码网络 信息隐藏 差异化压缩
在线阅读 下载PDF
基于深度学习的数据同化裂隙网络分布模拟
17
作者 徐朝晖 康学远 +4 位作者 于军 龚绪龙 韩正 吴吉春 施小清 《水文地质工程地质》 北大核心 2026年第1期66-79,共14页
准确表征裂隙网络的空间分布是描述裂隙介质中地下水流动和污染物运移的关键前提。由于裂隙介质中裂隙和基质参数的强非高斯性,当观测数据有限时,常用的随机反演方法(如地质统计学方法)因高斯假设先验,导致推估得到的裂隙网络高渗区域... 准确表征裂隙网络的空间分布是描述裂隙介质中地下水流动和污染物运移的关键前提。由于裂隙介质中裂隙和基质参数的强非高斯性,当观测数据有限时,常用的随机反演方法(如地质统计学方法)因高斯假设先验,导致推估得到的裂隙网络高渗区域容易过于平滑。本研究提出一种基于深度学习的反演框架来表征裂隙网络,利用卷积变分自编码器(convolutional variational autoencoder,CVAE)识别图像的优势,通过学习裂隙先验信息提取其空间模式。为了增强该反演框架在野外实际的适用性,在训练样本构建中将裂隙数量设置为特定数量区间的随机分布。将训练后的CVAE与基于集合的数据同化方法(ensemble smoother multiple data assimilation,ESMDA)集成,通过水力层析成像技术(hydraulic tomography,HT)获取的水头数据估计裂隙场。基于二维裂隙网络数值算例验证该框架的反演性能。训练后的CVAE成功再现了裂隙网络的非高斯特性。相比于标准的ESMDA方法,所构建框架CVAE-ESMDA刻画的裂隙网络精度从65.5%提升至83.3%,溶质运移预测平均误差降低31.7%。进一步探讨观测数据量对于CVAE-ESMDA性能的影响,研究发现相比1512个水头观测数据,反演框架在504个水头观测数据情况下仍能刻画出裂隙网络的大体分布与连通情况,但具体裂隙的刻画精度有所下降,从而影响了溶质运移趋势预测的准确性,整体溶质运移预测的平均误差增加17.1%。提出的CVAE-ESMDA反演框架能有效克服裂隙含水层参数非高斯特性并高效学习裂隙网络的结构特征,在不同观测数据量下均能一定程度地刻画出裂隙网络分布特征。 展开更多
关键词 裂隙网络 卷积变分自编码器 反演 数据同化方法 水力层析成像 深度学习
在线阅读 下载PDF
基于贝叶斯网的故障根因分析
18
作者 刘华帅 陶厚国 +1 位作者 岳昆 段亮 《计算机科学》 北大核心 2026年第3期143-150,共8页
故障根因分析旨在找到导致特定问题、故障或事件发生的原因,是多个领域中追踪溯源的重要支撑技术,但现有方法在效率、准确性和稳定性等方面仍不能满足故障根因分析任务的实际需求。对此,将贝叶斯网作为相关属性之间依赖关系表示和推理... 故障根因分析旨在找到导致特定问题、故障或事件发生的原因,是多个领域中追踪溯源的重要支撑技术,但现有方法在效率、准确性和稳定性等方面仍不能满足故障根因分析任务的实际需求。对此,将贝叶斯网作为相关属性之间依赖关系表示和推理的知识框架,提出基于贝叶斯网的故障根因分析方法。首先,针对高维数据和稀疏样本带来的挑战,提出基于向量量化自编码器的高维属性约简算法,并给出α-BIC评分准则,高效地学习根因贝叶斯网(Root Cause Bayesian Network,RCBN)。随后,基于贝叶斯网嵌入技术实现RCBN的高效推理,高效计算各原因条件下故障产生的可能性,进而使用因果模型中的Blame机制度量各原因对给定故障的贡献度,从而实现故障根因分析。在3个公共数据集和3个合成数据集上的实验结果表明,所提方法的平均检测准确性和效率明显优于对比方法,在CHILD数据集上精度提升了7%,运行时间快了60%。 展开更多
关键词 故障根因分析 贝叶斯网 向量量化自编码器 贝叶斯信息准则 根因贡献度
在线阅读 下载PDF
ICBV:一种基于BERT变分自编码的半监督意图聚类方法
19
作者 赵锦栎 勾智楠 高凯 《计算机工程与科学》 北大核心 2026年第2期277-285,共9页
意图聚类在自然语言处理中具有重要价值,面对有限的标记数据时,现有方法往往难以捕捉到离散文本表示中复杂的语义信息,并且未标记数据常常包含噪声,直接为其赋予伪标签可能会对模型的训练造成负面影响,因此如何有效利用未标记数据并减... 意图聚类在自然语言处理中具有重要价值,面对有限的标记数据时,现有方法往往难以捕捉到离散文本表示中复杂的语义信息,并且未标记数据常常包含噪声,直接为其赋予伪标签可能会对模型的训练造成负面影响,因此如何有效利用未标记数据并减少噪声成为关键问题。为了解决这一问题,提出了一种名为ICBV的半监督聚类方法。该方法结合少量有标签数据和基于BERT编码的变分自编码器进行预训练表示学习,并随后在训练阶段采用质心引导策略。ICBV能够对输入文本进行编码并计算潜在变量,从而捕捉数据的潜在空间表示。ICBV相较传统聚类方法,还利用了深度学习的特性,以便更有效地捕捉数据的复杂结构和非线性关系。在BANKING77数据集上的不同已知类比率设置下的实验中,准确率相对最新基线方法有所提高,验证了VAE编码获得潜在变量表示的有效性和聚类方法的鲁棒性。该方法为自然语言处理领域中意图聚类中的标记数据不足和噪声问题提供了一种解决方案。 展开更多
关键词 半监督聚类 意图聚类 变分自编码器(VAE)
在线阅读 下载PDF
基于变分自编码器的船舶柴油机故障状态检测
20
作者 邹思涵 尚前明 杨雨鑫 《舰船科学技术》 北大核心 2026年第4期63-69,共7页
针对柴油机获取故障数据较难的问题,利用AVL-BOOST模块化的方法建立柴油机气缸模型、中冷器模型等各系统模型,搭建柴油机的整机模型,采用额定工况数据验证了模型精度较高。模型模拟喷油提前、排气滞后等7种单一故障和3种复合故障,分析... 针对柴油机获取故障数据较难的问题,利用AVL-BOOST模块化的方法建立柴油机气缸模型、中冷器模型等各系统模型,搭建柴油机的整机模型,采用额定工况数据验证了模型精度较高。模型模拟喷油提前、排气滞后等7种单一故障和3种复合故障,分析不同故障引起的参数变化,选取了油耗、有效功率、最大燃烧压力等12种参数作为特征参数,构造故障样本集,为故障状态检测提供了数据支撑。为实现柴油机运行状态精准检测,采用变分自编码器模型(VAE)对柴油机进行故障检测,利用正常数据确定统计量阈值判断是否发生故障,实验结果表明,对单一故障和复合故障2种类型检测都取得了较好的效果。 展开更多
关键词 船舶柴油机 建模与仿真 变分自编码器 故障检测
在线阅读 下载PDF
上一页 1 2 21 下一页 到第
使用帮助 返回顶部