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Advancing Breast Cancer Molecular Subtyping:A Comparative Study of Convolutional Neural Networks and Vision Transformers on Mammograms
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作者 Chee Chin Lim Hui Wen Tiu +2 位作者 Qi Wei Oung Chiew Chea Lau Xiao Jian Tan 《Computers, Materials & Continua》 2026年第3期1287-1308,共22页
critical for guiding treatment and improving patient outcomes.Traditional molecular subtyping via immuno-histochemistry(IHC)test is invasive,time-consuming,and may not fully represent tumor heterogeneity.This study pr... critical for guiding treatment and improving patient outcomes.Traditional molecular subtyping via immuno-histochemistry(IHC)test is invasive,time-consuming,and may not fully represent tumor heterogeneity.This study proposes a non-invasive approach using digital mammography images and deep learning algorithm for classifying breast cancer molecular subtypes.Four pretrained models,including two Convolutional Neural Networks(MobileNet_V3_Large and VGG-16)and two Vision Transformers(ViT_B_16 and ViT_Base_Patch16_Clip_224)were fine-tuned to classify images into HER2-enriched,Luminal,Normal-like,and Triple Negative subtypes.Hyperparameter tuning,including learning rate adjustment and layer freezing strategies,was applied to optimize performance.Among the evaluated models,ViT_Base_Patch16_Clip_224 achieved the highest test accuracy(94.44%),with equally high precision,recall,and F1-score of 0.94,demonstrating excellent generalization.MobileNet_V3_Large achieved the same accuracy but showed less training stability.In contrast,VGG-16 recorded the lowest performance,indicating a limitation in its generalizability for this classification task.The study also highlighted the superior performance of the Vision Transformer models over CNNs,particularly due to their ability to capture global contextual features and the benefit of CLIP-based pretraining in ViT_Base_Patch16_Clip_224.To enhance clinical applicability,a graphical user interface(GUI)named“BCMS Dx”was developed for streamlined subtype prediction.Deep learning applied to mammography has proven effective for accurate and non-invasive molecular subtyping.The proposed Vision Transformer-based model and supporting GUI offer a promising direction for augmenting diagnostic workflows,minimizing the need for invasive procedures,and advancing personalized breast cancer management. 展开更多
关键词 Artificial intelligence breast cancer classification convolutional neural network deep learning hyperparameter tuning MAMMOGRAPHY medical imaging molecular subtypes vision transformer
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基于改进时间融合Transformers的中国大豆需求预测方法
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作者 刘佳佳 秦晓婧 +5 位作者 李乾川 许世卫 赵继春 王一罡 熊露 梁晓贺 《智慧农业(中英文)》 2025年第4期187-199,共13页
[目的/意义]精准预测大豆需求对保障国家粮食安全、优化产业决策与应对国际贸易变局有着重要的现实意义,而利用时间融合Transformers(Temporal Fusion Transformers,TFT)模型开展中国大豆需求预测时,在特征交互层与注意力权重分配等方... [目的/意义]精准预测大豆需求对保障国家粮食安全、优化产业决策与应对国际贸易变局有着重要的现实意义,而利用时间融合Transformers(Temporal Fusion Transformers,TFT)模型开展中国大豆需求预测时,在特征交互层与注意力权重分配等方面仍存在一定局限。为此,亟需探索一种基于改进TFT模型的预测方法,以提升需求预测的准确性与可解释性。[方法]本研究将深度学习的TFT模型应用到中国大豆需求预测中,提出了一种基于多层动态特征交互(Multi-layer Dynamic Feature Interaction,MDFI)与自适应注意力权重优化(Adaptive Attention Weight Optimization,AAWO)改进的MA-TFT(Improved TFT Model Based on MDFI and AAWO)模型。对包含1980—2024年4652个相关指标的中国大豆需求分析数据集进行数据预处理和特征工程,设计实验将MA-TFT模型分别与自回归差分移动平均模型(Autoregressive Integrated Moving Average Model,ARIMA)、长短期记忆网络(Long Short-Term Memory,LSTM)模型及TFT模型进行预测性能对比,进行了消融实验,同时利用SHAP(SHapley Additive exPlanations)工具可解释性分析影响中国大豆需求的关键特征变量,开展了未来10年的中国大豆需求量预测。[结果和讨论]MA-TFT模型的均方误差(Mean Squared Error,MSE)、平均绝对百分比误差(Mean Absolute Percentage Error,MAPE)分别为0.036和5.89%,决定系数R^(2)为0.91,均高于对比模型,均方根误差(Root Mean Square Error,RMSE)和MAPE分别较基准模型TFT累计降低21.84%和3.44%,表明改进TFT的MA-TFT模型能够捕捉特征间复杂关系,提升预测性能;研究利用SHAP工具可解释性分析发现,MA-TFT模型对影响中国大豆需求关键特征变量的解释稳定性较高;预计2025、2030和2034年中国大豆需求量分别达到11799万吨、11033万吨和11378万吨。[结论]基于改进TFT的MA-TFT模型方法为解决现有大豆需求预测方法精度不足、可解释性不强的实际问题提供了解决思路,也为其他农产品时间序列预测的方法优化与应用提供了参考和借鉴。 展开更多
关键词 时间融合transformers(TFT) 大豆需求预测 多层动态特征交互 自适应注意力权重优化 可解释性分析
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新解码器的CNNs-Transformers融合网络及其病理图像肿瘤分割应用 被引量:1
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作者 马丽晶 王朝立 +2 位作者 孙占全 程树群 王康 《小型微型计算机系统》 北大核心 2025年第6期1442-1449,共8页
病理图像是肿瘤诊断的"金标准",但超高分辨率的病理图像使得医生需要消耗大量的精力和时间,而且诊断结果主观性比较强.随着人工智能技术的发展,深度学习模型提供了计算机代替人对病理图像进行快速、准确和可靠诊断的可能性.然... 病理图像是肿瘤诊断的"金标准",但超高分辨率的病理图像使得医生需要消耗大量的精力和时间,而且诊断结果主观性比较强.随着人工智能技术的发展,深度学习模型提供了计算机代替人对病理图像进行快速、准确和可靠诊断的可能性.然而,目前大多数的网络更注重如何在编码器部分提取更准确的特征,而对于同等重要的解码器部分的结构设计研究则稍显不足.针对该问题,本文提出了由三类上采样模块组成的新网络,而编码器部分采用Swin Transformer和ConvNeXt作为网络的双分支并行独立结构.三类上采样模块分别是多重转置卷积采样、双线性上采样和Swin Transformer上采样,其特点是可以充分利用病理图像特征之间局部和全局的依赖关系.该网络分别在肝癌数据集和GLAS数据集上进行了验证,并与不同类型的主流网络进行了对比,性能指标皆达到比较好的结果. 展开更多
关键词 医学图像分割 深度学习 卷积神经网络 Swin Transformer
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Development of an Electromagnetic-Thermal Circuit Model for Single-Phase Three-Limb Transformers
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作者 Yidan Hu Jiawen Yu +3 位作者 Zhaoyu Zhang Xuanrui Zhang Junhao Li Roberto Ottoboni 《High Voltage》 2025年第6期1545-1557,共13页
Analysing the heat states of transformers under DC bias requires careful consideration of their own structural and material characteristics.Although the 3D finite element method(FEM)is a reliable way of simulating all... Analysing the heat states of transformers under DC bias requires careful consideration of their own structural and material characteristics.Although the 3D finite element method(FEM)is a reliable way of simulating all the details of transformers,it may be time-consuming or have encountered convergence difficulties due to the complex internal structure of the transformer.To address the issues,this paper proposes a fast calculation model for estimating the top-oil temperature rise and the winding hotspot temperature rise of single-phase three-limb transformers under DC bias.This model is based on the coupling principle of electric circuits,magnetic circuits and thermal circuits,and it considers the winding loss and core loss of the transformer under DC bias as key factors linking electromagnetic and thermal effects.All the model parameters can be obtained from nameplate data and regular test data to ensure the method's engineering practicality.The results were compared with 3D FEM,demonstrating favourable performance in terms of computational speed and availability. 展开更多
关键词 convergence difficulties d finite element method fem transformers single phase three limb transformers electromagnetic thermal circuit model calculation model analysing heat states winding hotspot temper
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Generating Abstractive Summaries from Social Media Discussions Using Transformers
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作者 Afrodite Papagiannopoulou Chrissanthi Angeli Mazida Ahmad 《Open Journal of Applied Sciences》 2025年第1期239-258,共20页
The rise of social media platforms has revolutionized communication, enabling the exchange of vast amounts of data through text, audio, images, and videos. These platforms have become critical for sharing opinions and... The rise of social media platforms has revolutionized communication, enabling the exchange of vast amounts of data through text, audio, images, and videos. These platforms have become critical for sharing opinions and insights, influencing daily habits, and driving business, political, and economic decisions. Text posts are particularly significant, and natural language processing (NLP) has emerged as a powerful tool for analyzing such data. While traditional NLP methods have been effective for structured media, social media content poses unique challenges due to its informal and diverse nature. This has spurred the development of new techniques tailored for processing and extracting insights from unstructured user-generated text. One key application of NLP is the summarization of user comments to manage overwhelming content volumes. Abstractive summarization has proven highly effective in generating concise, human-like summaries, offering clear overviews of key themes and sentiments. This enhances understanding and engagement while reducing cognitive effort for users. For businesses, summarization provides actionable insights into customer preferences and feedback, enabling faster trend analysis, improved responsiveness, and strategic adaptability. By distilling complex data into manageable insights, summarization plays a vital role in improving user experiences and empowering informed decision-making in a data-driven landscape. This paper proposes a new implementation framework by fine-tuning and parameterizing Transformer Large Language Models to manage and maintain linguistic and semantic components in abstractive summary generation. The system excels in transforming large volumes of data into meaningful summaries, as evidenced by its strong performance across metrics like fluency, consistency, readability, and semantic coherence. 展开更多
关键词 Abstractive Summarization transformers Social Media Summarization Transformer Language Models
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Leveraging Transformers for Detection of Arabic Cyberbullying on Social Media: Hybrid Arabic Transformers
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作者 Amjad A.Alsuwaylimi Zaid S.Alenezi 《Computers, Materials & Continua》 2025年第5期3165-3185,共21页
Cyberbullying is a remarkable issue in the Arabic-speaking world,affecting children,organizations,and businesses.Various efforts have been made to combat this problem through proposed models using machine learning(ML)... Cyberbullying is a remarkable issue in the Arabic-speaking world,affecting children,organizations,and businesses.Various efforts have been made to combat this problem through proposed models using machine learning(ML)and deep learning(DL)approaches utilizing natural language processing(NLP)methods and by proposing relevant datasets.However,most of these endeavors focused predominantly on the English language,leaving a substantial gap in addressing Arabic cyberbullying.Given the complexities of the Arabic language,transfer learning techniques and transformers present a promising approach to enhance the detection and classification of abusive content by leveraging large and pretrained models that use a large dataset.Therefore,this study proposes a hybrid model using transformers trained on extensive Arabic datasets.It then fine-tunes the hybrid model on a newly curated Arabic cyberbullying dataset collected from social media platforms,in particular Twitter.Additionally,the following two hybrid transformer models are introduced:the first combines CAmelid Morphologically-aware pretrained Bidirectional Encoder Representations from Transformers(CAMeLBERT)with Arabic Generative Pre-trained Transformer 2(AraGPT2)and the second combines Arabic BERT(AraBERT)with Cross-lingual Language Model-RoBERTa(XLM-R).Two strategies,namely,feature fusion and ensemble voting,are employed to improve the model performance accuracy.Experimental results,measured through precision,recall,F1-score,accuracy,and AreaUnder the Curve-Receiver Operating Characteristic(AUC-ROC),demonstrate that the combined CAMeLBERT and AraGPT2 models using feature fusion outperformed traditional DL models,such as Long Short-Term Memory(LSTM)and Bidirectional Long Short-Term Memory(BiLSTM),as well as other independent Arabic-based transformer models. 展开更多
关键词 CYBERBULLYING transformers pre-trained models arabic cyberbullying detection deep learning
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Analysis of the effects of strong stray magnetic fields generated by tokamak device on transformers assembled in electronic power converters
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作者 Xingjian ZHAO Ge GAO +2 位作者 Li JIANG Yong YANG Hong LEI 《Plasma Science and Technology》 2025年第5期81-93,共13页
As the plasma current power in tokamak devices increases,a significant number of stray magnetic fields are generated around the equipment.These stray magnetic fields can disrupt the operation of electronic power devic... As the plasma current power in tokamak devices increases,a significant number of stray magnetic fields are generated around the equipment.These stray magnetic fields can disrupt the operation of electronic power devices,particularly transformers in switched-mode power supplies.Testing flyback converters with transformers under strong background magnetic fields highlights electromagnetic compatibility(EMC)issues for such switched-mode power supplies.This study utilizes finite element analysis software to simulate the electromagnetic environment of switched-mode power supply transformers and investigates the impact of variations in different magnetic field parameters on the performance of switched-mode power supplies under strong stray magnetic fields.The findings indicate that EMC issues are associated with transformer core saturation and can be alleviated through appropriate configurations of the core size,air gap,fillet radius,and installation direction.This study offers novel solutions for addressing EMC issues in high magnetic field environments. 展开更多
关键词 transformers magnetic field interference magnetic components power electronics magnetic field simulation
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Improving Fashion Sentiment Detection on X through Hybrid Transformers and RNNs
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作者 Bandar Alotaibi Aljawhara Almutarie +1 位作者 Shuaa Alotaibi Munif Alotaibi 《Computers, Materials & Continua》 2025年第9期4451-4467,共17页
X(formerly known as Twitter)is one of the most prominent social media platforms,enabling users to share short messages(tweets)with the public or their followers.It serves various purposes,from real-time news dissemina... X(formerly known as Twitter)is one of the most prominent social media platforms,enabling users to share short messages(tweets)with the public or their followers.It serves various purposes,from real-time news dissemination and political discourse to trend spotting and consumer engagement.X has emerged as a key space for understanding shifting brand perceptions,consumer preferences,and product-related sentiment in the fashion industry.However,the platform’s informal,dynamic,and context-dependent language poses substantial challenges for sentiment analysis,mainly when attempting to detect sarcasm,slang,and nuanced emotional tones.This study introduces a hybrid deep learning framework that integrates Transformer encoders,recurrent neural networks(i.e.,Long Short-Term Memory(LSTM)and Gated Recurrent Unit(GRU)),and attention mechanisms to improve the accuracy of fashion-related sentiment classification.These methods were selected due to their proven strength in capturing both contextual dependencies and sequential structures,which are essential for interpreting short-form text.Our model was evaluated on a dataset of 20,000 fashion tweets.The experimental results demonstrate a classification accuracy of 92.25%,outperforming conventional models such as Logistic Regression,Linear Support Vector Machine(SVM),and even standalone LSTM by a margin of up to 8%.This improvement highlights the importance of hybrid architectures in handling noisy,informal social media data.This study’s findings offer strong implications for digital marketing and brand management,where timely sentiment detection is critical.Despite the promising results,challenges remain regarding the precise identification of negative sentiments,indicating that further work is needed to detect subtle and contextually embedded expressions. 展开更多
关键词 Sentiment analysis deep learning natural language processing transformers recurrent neural networks
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Transformers for Multi-Modal Image Analysis in Healthcare
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作者 Sameera V Mohd Sagheer Meghana K H +2 位作者 P M Ameer Muneer Parayangat Mohamed Abbas 《Computers, Materials & Continua》 2025年第9期4259-4297,共39页
Integrating multiple medical imaging techniques,including Magnetic Resonance Imaging(MRI),Computed Tomography,Positron Emission Tomography(PET),and ultrasound,provides a comprehensive view of the patient health status... Integrating multiple medical imaging techniques,including Magnetic Resonance Imaging(MRI),Computed Tomography,Positron Emission Tomography(PET),and ultrasound,provides a comprehensive view of the patient health status.Each of these methods contributes unique diagnostic insights,enhancing the overall assessment of patient condition.Nevertheless,the amalgamation of data from multiple modalities presents difficulties due to disparities in resolution,data collection methods,and noise levels.While traditional models like Convolutional Neural Networks(CNNs)excel in single-modality tasks,they struggle to handle multi-modal complexities,lacking the capacity to model global relationships.This research presents a novel approach for examining multi-modal medical imagery using a transformer-based system.The framework employs self-attention and cross-attention mechanisms to synchronize and integrate features across various modalities.Additionally,it shows resilience to variations in noise and image quality,making it adaptable for real-time clinical use.To address the computational hurdles linked to transformer models,particularly in real-time clinical applications in resource-constrained environments,several optimization techniques have been integrated to boost scalability and efficiency.Initially,a streamlined transformer architecture was adopted to minimize the computational load while maintaining model effectiveness.Methods such as model pruning,quantization,and knowledge distillation have been applied to reduce the parameter count and enhance the inference speed.Furthermore,efficient attention mechanisms such as linear or sparse attention were employed to alleviate the substantial memory and processing requirements of traditional self-attention operations.For further deployment optimization,researchers have implemented hardware-aware acceleration strategies,including the use of TensorRT and ONNX-based model compression,to ensure efficient execution on edge devices.These optimizations allow the approach to function effectively in real-time clinical settings,ensuring viability even in environments with limited resources.Future research directions include integrating non-imaging data to facilitate personalized treatment and enhancing computational efficiency for implementation in resource-limited environments.This study highlights the transformative potential of transformer models in multi-modal medical imaging,offering improvements in diagnostic accuracy and patient care outcomes. 展开更多
关键词 Multi-modal image analysis medical imaging deep learning image segmentation disease detection multi-modal fusion Vision transformers(ViTs) precision medicine clinical decision support
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Token Masked Pose Transformers Are Efficient Learners
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作者 Xinyi Song Haixiang Zhang Shaohua Li 《Computers, Materials & Continua》 2025年第5期2735-2750,共16页
In recent years,Transformer has achieved remarkable results in the field of computer vision,with its built-in attention layers effectively modeling global dependencies in images by transforming image features into tok... In recent years,Transformer has achieved remarkable results in the field of computer vision,with its built-in attention layers effectively modeling global dependencies in images by transforming image features into token forms.However,Transformers often face high computational costs when processing large-scale image data,which limits their feasibility in real-time applications.To address this issue,we propose Token Masked Pose Transformers(TMPose),constructing an efficient Transformer network for pose estimation.This network applies semantic-level masking to tokens and employs three different masking strategies to optimize model performance,aiming to reduce computational complexity.Experimental results show that TMPose reduces computational complexity by 61.1%on the COCO validation dataset,with negligible loss in accuracy.Additionally,our performance on the MPII dataset is also competitive.This research not only enhances the accuracy of pose estimation but also significantly reduces the demand for computational resources,providing new directions for further studies in this field. 展开更多
关键词 Pattern recognition image processing neural network pose transformer
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Data-driven measurement performance evaluation of voltage transformers in electric railway traction power supply systems
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作者 Zhaoyang Li Muqi Sun +5 位作者 Jun Zhu Haoyu Luo Qi Wang Haitao Hu Zhengyou He Ke Wang 《Railway Engineering Science》 2025年第2期311-323,共13页
Critical for metering and protection in electric railway traction power supply systems(TPSSs),the measurement performance of voltage transformers(VTs)must be timely and reliably monitored.This paper outlines a three-s... Critical for metering and protection in electric railway traction power supply systems(TPSSs),the measurement performance of voltage transformers(VTs)must be timely and reliably monitored.This paper outlines a three-step,RMS data only method for evaluating VTs in TPSSs.First,a kernel principal component analysis approach is used to diagnose the VT exhibiting significant measurement deviations over time,mitigating the influence of stochastic fluctuations in traction loads.Second,a back propagation neural network is employed to continuously estimate the measurement deviations of the targeted VT.Third,a trend analysis method is developed to assess the evolution of the measurement performance of VTs.Case studies conducted on field data from an operational TPSS demonstrate the effectiveness of the proposed method in detecting VTs with measurement deviations exceeding 1%relative to their original accuracy levels.Additionally,the method accurately tracks deviation trends,enabling the identification of potential early-stage faults in VTs and helping prevent significant economic losses in TPSS operations. 展开更多
关键词 Voltage transformer Traction power supply system Measurement performance Data-driven evaluation Abrupt change detection Bootstrap confidence interval
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Impact of Component Structure on Vibration and Noise of Converter Transformers Under Harmonic Excitation
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作者 Hao Wang Li Zhang +1 位作者 Youliang Sun Liang Zou 《High Voltage》 2025年第6期1571-1581,共11页
The internal component structure of the converter transformer plays an extremely important role in the generation and propagation of vibration noise.In order to comprehensively reveal the influence of the component st... The internal component structure of the converter transformer plays an extremely important role in the generation and propagation of vibration noise.In order to comprehensively reveal the influence of the component structure on the vibration and noise of converter transformers,this paper conducted vibration and noise experiments on different combinations of three iron core structures,four winding structures,two oil tank structures,two foot insulation structures and three positioning structures under different frequency harmonic excitations in a semi-anechoic chamber environment.The results show that the optimal configuration for minimising noise in converter transformers comprises the following components:an entanglement internal screen winding within the coil assembly,a 7.2 mm six-step-123 iron core,a cross-shaped reinforced oil tank,bottom foot insulation,an upper eccentric circle design and lower pouring positioning. 展开更多
关键词 positioning structures converter transformer winding structurestwo converter transformersthis foot insulation structures iron core structuresfour oil tank structurestwo component structure
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Research on the Selection and Layout Scheme of Main Transformers in the Primary Electrical Design of New Energy Step-Up Stations
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作者 Yuekai Liao 《Journal of Electronic Research and Application》 2025年第4期254-260,共7页
This paper focuses on the research of the main transformer selection and layout scheme for new energy step-up substations.From the perspective of engineering design,it analyzes the principles of main transformer selec... This paper focuses on the research of the main transformer selection and layout scheme for new energy step-up substations.From the perspective of engineering design,it analyzes the principles of main transformer selection,key parameters,and their matching with the characteristics of new energy.It also explores the layout methods and optimization strategies.Combined with typical case studies,optimization suggestions are proposed for the design of main transformers in new energy step-up substations.The research shows that rational main transformer selection and scientific layout schemes can better adapt to the characteristics of new energy projects while effectively improving land use efficiency and economic viability.This study can provide technical experience support for the design of new energy projects. 展开更多
关键词 New energy step-up substation Engineering design Main transformer selection
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基于双重并行任务的无人机小目标两阶段检测方法
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作者 杨艺 朱江睿 +3 位作者 王科平 张高鹏 钱伟 王田 《模式识别与人工智能》 北大核心 2026年第1期31-51,共21页
目标在图像中的尺寸过小是无人机目标检测面临的主要挑战之一,特别是当无人机飞行高度较高且成像分辨率较低时,小目标特征极易在深度神经网络的深层特征中弥散.为此,文中提出基于双重并行任务的无人机小目标两阶段检测方法,并行任务包... 目标在图像中的尺寸过小是无人机目标检测面临的主要挑战之一,特别是当无人机飞行高度较高且成像分辨率较低时,小目标特征极易在深度神经网络的深层特征中弥散.为此,文中提出基于双重并行任务的无人机小目标两阶段检测方法,并行任务包含小目标检测任务与超分辨率重建任务.在超分辨率重建任务分支中,构建空间先验模块和窗口注意力引导模块.小目标检测任务分支以Swin Transformer为基础,并且分别由空间先验模块和窗口注意力引导模块进行浅层特征的空间信息和深层特征的注意力的超分辨率重建.两阶段检测方法分为训练阶段和推理阶段.在训练阶段,超分辨率重建任务分支均以高分辨率特征为标签,从而增强小目标检测任务分支对细节特征的提取能力.在推理阶段,仅保留小目标检测任务分支,可提升方法的推理速度,降低资源开销.在公共数据集VisDrone和自制无人机数据集JZ-UAV上的实验表明,文中方法识别精度较高. 展开更多
关键词 无人机(UAV) Swin TRANSFORMER 小目标检测 超分辨率重建
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基于图像匹配的高空大斜视无源目标定位
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作者 贾平 李昌灏 +3 位作者 孙辉 宋悦铭 祃卓荦 徐芳 《光学精密工程》 北大核心 2026年第1期124-138,共15页
提出一种基于图像匹配的无源定位方法,通过引入基于Transformer的特征增强与MiHo聚类筛选的两步匹配策略,减轻了高空大斜视条件下传统无源定位算法因微小角度误差导致的定位精度下降程度。根据粗定位结果与飞行参数对航拍图像进行近似... 提出一种基于图像匹配的无源定位方法,通过引入基于Transformer的特征增强与MiHo聚类筛选的两步匹配策略,减轻了高空大斜视条件下传统无源定位算法因微小角度误差导致的定位精度下降程度。根据粗定位结果与飞行参数对航拍图像进行近似正射变换,并截取对应区域的卫星图像。采用RepVGG提取图像粗特征,通过互最近邻实现初步匹配,并结合MiHo与归一化互相关(Normalized Cross Correlation,NCC)筛选匹配点对。最后,借助Transformer模块完成精细化匹配,再根据精匹配结果构建角度误差修正矩阵,多次迭代修正系统误差。实验结果表明,所提方法的定位精度较传统方法有较大幅度提升,在典型应用场景下提升约70%,在斜距90 km的情况下,定位精度可维持在120 m左右。该方法突破了传统无源定位对角度精度的高度依赖,验证了基于图像匹配的无源定位路径的可行性与有效性。 展开更多
关键词 图像匹配 目标定位 航空光电系统 无源定位 大斜视 TRANSFORMER
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面向遥感图像超分辨率重建的跨尺度余弦注意力网络
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作者 李智杰 宋易宸 +3 位作者 李昌华 董玮 张颉 介军 《计算机工程与应用》 北大核心 2026年第1期285-296,共12页
为了解决现有遥感图像超分辨率网络无法充分利用跨尺度特征、参数过多和计算量大的问题,提出一种面向遥感图像超分辨率重建的跨尺度余弦注意力网络。通过引入特征蒸馏机制设计了一种级联特征蒸馏块,用来提取具有不同感知场和高频信息的... 为了解决现有遥感图像超分辨率网络无法充分利用跨尺度特征、参数过多和计算量大的问题,提出一种面向遥感图像超分辨率重建的跨尺度余弦注意力网络。通过引入特征蒸馏机制设计了一种级联特征蒸馏块,用来提取具有不同感知场和高频信息的更丰富的区域特征,同时保持模型轻量化。在级联特征蒸馏块中嵌入一种多分支空间注意力模块以进一步提升网络对关键空间信息的捕捉能力。此外,提出的跨尺度余弦注意力层可以在不增加计算复杂度的情况下有效计算高维和低维特征之间的相关性,从而增强模型对不同尺度特征的处理能力,而且其中的高效余弦自注意力机制解决了网络注意力被特定像素支配的问题,增强网络关注更多特征的能力。在UC Merced和AID数据集上的实验结果表明,所提算法与当前主流的超分辨率重建算法相比以相对较低的计算成本获得了更好的峰值信噪比和结构相似度,重建后的图像恢复了更多的纹理细节信息,验证了所提网络可以在较好地平衡模型轻量化的同时提升超分辨率重建性能。 展开更多
关键词 遥感图像 超分辨率重建 TRANSFORMER 轻量级 跨尺度
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计及预案式失配冲击的响应驱动频率稳定紧急切负荷策略
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作者 孙正龙 刘勇 +5 位作者 陈威翰 章锐 刘铖 华文 张程铭 蔡国伟 《电力系统保护与控制》 北大核心 2026年第1期117-129,共13页
在新型电力系统复杂工况下,以策略表为主体、通过“离线仿真、在线匹配”的预案式频率稳定控制方案存在较高失配风险,甚至因调控失当引发二次冲击,严重威胁电力系统的安全稳定运行。提出一种计及预案式失配冲击的响应驱动频率稳定紧急... 在新型电力系统复杂工况下,以策略表为主体、通过“离线仿真、在线匹配”的预案式频率稳定控制方案存在较高失配风险,甚至因调控失当引发二次冲击,严重威胁电力系统的安全稳定运行。提出一种计及预案式失配冲击的响应驱动频率稳定紧急切负荷策略。该策略动作在预案式控制之后,是对预案式控制的有益补充,能够有效提升系统频率稳定性。首先建立了基于系统频率响应(system frequency response,SFR)模型辨识的频率稳定切负荷量计算方法。提出了基于频率稀疏量测的SFR模型辨识方法,在此基础上建立了含稳定控制的SFR模型,根据频率稳定控制目标迭代求解切负荷量。其次,建立了基于Transformer网络的频率控制敏感点挖掘模型,通过分析关键发电机母线节点频率时序值和频率控制敏感点的映射关系,实现响应驱动的频率控制敏感点在线挖掘。最后,按照敏感点排序快速分配控制措施总量,构建频率稳定紧急控制方案。在某实际交直流混联万节点仿真系统验证了所提方法的有效性。 展开更多
关键词 预案式控制 频率稳定 紧急控制 频率响应模型 TRANSFORMER
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用于低剂量CT图像降噪的多路特征生成对抗网络
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作者 王丽芳 任文婧 +2 位作者 郭晓东 张荣国 胡立华 《计算机应用》 北大核心 2026年第1期270-279,共10页
近些年,把生成对抗网络(GAN)应用于低剂量计算机断层扫描(LDCT)图像降噪取得了显著进展。然而,现有方法存在对复杂噪声分布建模能力不足以及结构细节保留能力有限等问题。因此,提出一种用于LDCT图像降噪的多路特征GAN——Trident GAN。... 近些年,把生成对抗网络(GAN)应用于低剂量计算机断层扫描(LDCT)图像降噪取得了显著进展。然而,现有方法存在对复杂噪声分布建模能力不足以及结构细节保留能力有限等问题。因此,提出一种用于LDCT图像降噪的多路特征GAN——Trident GAN。首先,设计特征引导生成器Trident Uformer,通过在U-Net结构的瓶颈层增加特征聚合注意力(FPA)模块解决U型结构空间分辨率较低的问题;其次,设计多路特征提取子模块Trident Block,并在3个分支中分别引入局部细节增强模块(LDEB)提取细节特征,轻量通道注意力模块(LCAB)增强通道特征,以及空间交互注意力模块(SIAB)获得重要空间特征;在SIAB中采用多级交互式注意力函数和评估机制设计空间上下文注意力机制(SCAM),解决单一注意力受限的问题;最后,设计多特征融合(MFF)模块来在三分支末端进行特征聚合,并对局部细节信息和全局语义信息进行建模,解决不同层次之间细节不连续的问题。此外,利用多尺度金字塔判别器(MSPD)在不同维度下检查生成结果的质量,指导具有全局一致性图像的生成。实验结果表明,在Mayo和Piglet数据集上,Trident GAN的平均峰值信噪比(PSNR)和结构相似性(SSIM)分别达到了31.5193 dB/0.8830和33.6331 dB/0.9478,与高频敏感GAN(HFSGAN)相比,参数量降低75.58%,测试时间缩短36.36%。可见,与HFSGAN等方法相比,Trident GAN可在较少的计算负荷下提高了图像质量。 展开更多
关键词 低剂量计算机断层扫描 图像降噪 注意力机制 TRANSFORMER 生成对抗网络
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深度学习在细胞图像自动分割中的应用与进展
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作者 王旭 王晓燕 +3 位作者 郭英慧 蔡肖红 刘艳艳 张文凯 《计算机工程与应用》 北大核心 2026年第2期73-91,共19页
细胞分割研究对于细胞形态学分析、疾病早期诊断、药物筛选以及个性化医疗具有重要意义。细胞图像分割作为一种核心任务,旨在从复杂的生物图像中提取细胞边界和结构,支持疾病诊断和研究。因此,对细胞进行精确分割是解决细胞形态学分析... 细胞分割研究对于细胞形态学分析、疾病早期诊断、药物筛选以及个性化医疗具有重要意义。细胞图像分割作为一种核心任务,旨在从复杂的生物图像中提取细胞边界和结构,支持疾病诊断和研究。因此,对细胞进行精确分割是解决细胞形态学分析、肿瘤检测以及药物筛选等生物医学问题的首要任务。深度学习以其良好的特征提取和自适应学习能力,近年来成为细胞图像自动分割领域的重要技术手段。为推动细胞图像分割研究,在介绍常用细胞图像分割性能评价指标的基础上,梳理了CNN、U-Net、Mask R-CNN、GAN、Transformer、GNN、弱监督学习、迁移学习和视觉大模型以及混合架构在细胞图像分割中的应用,并通过对各模型优缺点进行对比分析,明确了当前研究中存在的主要问题,并展望了未来的研究方向。 展开更多
关键词 细胞分割 深度学习 TRANSFORMER 弱监督学习 混合架构
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一种面向地图综合建筑多边形化简的Transformer模型
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作者 刘鹏程 成晓强 +2 位作者 肖天元 杨敏 艾廷华 《测绘学报》 北大核心 2026年第1期124-137,共14页
针对地图综合中建筑多边形化简方法依赖人工规则、自动化程度低且难以利用已有化简成果的问题,本文提出了一种基于Transformer机制的建筑多边形化简模型。该模型首先把建筑多边形映射至一定范围的网格空间,将建筑多边形的坐标串表达为... 针对地图综合中建筑多边形化简方法依赖人工规则、自动化程度低且难以利用已有化简成果的问题,本文提出了一种基于Transformer机制的建筑多边形化简模型。该模型首先把建筑多边形映射至一定范围的网格空间,将建筑多边形的坐标串表达为网格序列,从而获取建筑多边形化简前后的Token序列,构建出建筑多边形化简样本对数据;随后采用Transformer架构建立模型,基于样本数据利用模型的掩码自注意力机制学习点序列之间的依赖关系,最终逐点生成新的简化多边形,从而实现建筑多边形的化简。在训练过程中,模型使用结构化的样本数据,设计了忽略特定索引的交叉熵损失函数以提升化简质量。试验设计包括主试验与泛化验证两部分。主试验基于洛杉矶1∶2000建筑数据集,分别采用0.2、0.3和0.5 mm 3种网格尺寸对多边形进行编码,实现了目标比例尺为1∶5000与1∶10000的化简。试验结果表明,在0.3 mm的网格尺寸下模型性能最优,验证集上的化简结果与人工标注的一致率超过92.0%,且针对北京部分区域的建筑多边形数据的泛化试验验证了模型的迁移能力;与LSTM模型的对比分析显示,在参数规模相近的条件下,LSTM模型无法形成有效收敛,并生成可用结果。本文证实了Transformer在处理空间几何序列任务中的潜力,且能够有效复用已有化简样本,为智能建筑多边形化简提供了具有工程实用价值的途径。 展开更多
关键词 地图综合 建筑多边形化简 TOKENIZATION Transformer模型 上下文工程
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