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Joint Feature Encoding and Task Alignment Mechanism for Emotion-Cause Pair Extraction
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作者 Shi Li Didi Sun 《Computers, Materials & Continua》 SCIE EI 2025年第1期1069-1086,共18页
With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant importance.Emotion-cause pair extraction enables the identification of causal relationships between emotions... With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant importance.Emotion-cause pair extraction enables the identification of causal relationships between emotions and their triggers within a text,facilitating a deeper understanding of expressed sentiments and their underlying reasons.This comprehension is crucial for making informed strategic decisions in various business and societal contexts.However,recent research approaches employing multi-task learning frameworks for modeling often face challenges such as the inability to simultaneouslymodel extracted features and their interactions,or inconsistencies in label prediction between emotion-cause pair extraction and independent assistant tasks like emotion and cause extraction.To address these issues,this study proposes an emotion-cause pair extraction methodology that incorporates joint feature encoding and task alignment mechanisms.The model consists of two primary components:First,joint feature encoding simultaneously generates features for emotion-cause pairs and clauses,enhancing feature interactions between emotion clauses,cause clauses,and emotion-cause pairs.Second,the task alignment technique is applied to reduce the labeling distance between emotion-cause pair extraction and the two assistant tasks,capturing deep semantic information interactions among tasks.The proposed method is evaluated on a Chinese benchmark corpus using 10-fold cross-validation,assessing key performance metrics such as precision,recall,and F1 score.Experimental results demonstrate that the model achieves an F1 score of 76.05%,surpassing the state-of-the-art by 1.03%.The proposed model exhibits significant improvements in emotion-cause pair extraction(ECPE)and cause extraction(CE)compared to existing methods,validating its effectiveness.This research introduces a novel approach based on joint feature encoding and task alignment mechanisms,contributing to advancements in emotion-cause pair extraction.However,the study’s limitation lies in the data sources,potentially restricting the generalizability of the findings. 展开更多
关键词 Emotion-cause pair extraction interactive information enhancement joint feature encoding label consistency task alignment mechanisms
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Dual encoding feature filtering generalized attention UNET for retinal vessel segmentation
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作者 ISLAM Md Tauhidul WU Da-Wen +6 位作者 TANG Qing-Qing ZHAO Kai-Yang YIN Teng LI Yan-Fei SHANG Wen-Yi LIU Jing-Yu ZHANG Hai-Xian 《四川大学学报(自然科学版)》 北大核心 2025年第1期79-95,共17页
Retinal blood vessel segmentation is crucial for diagnosing ocular and cardiovascular diseases.Although the introduction of U-Net in 2015 by Olaf Ronneberger significantly advanced this field,yet issues like limited t... Retinal blood vessel segmentation is crucial for diagnosing ocular and cardiovascular diseases.Although the introduction of U-Net in 2015 by Olaf Ronneberger significantly advanced this field,yet issues like limited training data,imbalance data distribution,and inadequate feature extraction persist,hindering both the segmentation performance and optimal model generalization.Addressing these critical issues,the DEFFA-Unet is proposed featuring an additional encoder to process domain-invariant pre-processed inputs,thereby improving both richer feature encoding and enhanced model generalization.A feature filtering fusion module is developed to ensure the precise feature filtering and robust hybrid feature fusion.In response to the task-specific need for higher precision where false positives are very costly,traditional skip connections are replaced with the attention-guided feature reconstructing fusion module.Additionally,innovative data augmentation and balancing methods are proposed to counter data scarcity and distribution imbalance,further boosting the robustness and generalization of the model.With a comprehensive suite of evaluation metrics,extensive validations on four benchmark datasets(DRIVE,CHASEDB1,STARE,and HRF)and an SLO dataset(IOSTAR),demonstrate the proposed method’s superiority over both baseline and state-of-the-art models.Particularly the proposed method significantly outperforms the compared methods in cross-validation model generalization. 展开更多
关键词 Vessel segmentation Data balancing Data augmentation Dual encoder Attention Mechanism Model generalization
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Encoding converters for quantum communication networks
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作者 Hua-Xing Xu Shao-Hua Wang +2 位作者 Ya-Qi Song Ping Zhang Chang-Lei Wang 《Chinese Physics B》 2025年第5期64-69,共6页
Quantum communication networks,such as quantum key distribution(QKD)networks,typically employ the measurement-resend mechanism between two users using quantum communication devices based on different quantum encoding ... Quantum communication networks,such as quantum key distribution(QKD)networks,typically employ the measurement-resend mechanism between two users using quantum communication devices based on different quantum encoding types.To achieve direct communication between the devices with different quantum encoding types,in this paper,we propose encoding conversion schemes between the polarization bases(rectilinear,diagonal and circular bases)and the time-bin phase bases(two phase bases and time-bin basis)and design the quantum encoding converters.The theoretical analysis of the encoding conversion schemes is given in detail,and the basis correspondence of encoding conversion and the property of bit flip are revealed.The conversion relationship between polarization bases and time-bin phase bases can be easily selected by controlling a phase shifter.Since no optical switches are used in our scheme,the converter can be operated with high speed.The converters can also be modularized,which may be utilized to realize miniaturization in the future. 展开更多
关键词 quantum communication networks encoding conversion polarization encoding time-bin phase encoding
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A Blockchain-Based Covert Communication Model Based on Dynamic Base-K Encoding
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作者 Wang Zhujun Zhang Lejun +7 位作者 Li Xueqing Tian Zhihong Su Shen Qiu Jing Chen Huiling Qiu Tie Sergey Gataullin Guo Ran 《China Communications》 2025年第6期319-333,共15页
Blockchain,as a distributed ledger,inherently possesses tamper-resistant capabilities,creating a natural channel for covert communication.However,the immutable nature of data storage might introduce challenges to comm... Blockchain,as a distributed ledger,inherently possesses tamper-resistant capabilities,creating a natural channel for covert communication.However,the immutable nature of data storage might introduce challenges to communication security.This study introduces a blockchain-based covert communication model utilizing dynamic Base-K encoding.The proposed encoding scheme utilizes the input address sequence to determine K to encode the secret message and determines the order of transactions based on K,thus ensuring effective concealment of the message.The dynamic encoding parameters enhance flexibility and address issues related to identical transaction amounts for the same secret message.Experimental results demonstrate that the proposed method maintains smooth communication and low susceptibility to tampering,achieving commendable concealment and embedding rates. 展开更多
关键词 base-K encoding blockchain CONCEALMENT covert communication
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Image encoding-based bearing fault diagnosis:Review and challenges for high-speed trains
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作者 Huimin Li Lingfeng Li +1 位作者 Bin Liu Ge Xin 《High-Speed Railway》 2025年第3期251-259,共9页
High-Speed Trains (HSTs) have emerged as a mainstream mode of transportation in China, owing to their exceptional safety and efficiency. Ensuring the reliable operation of HSTs is of paramount economic and societal im... High-Speed Trains (HSTs) have emerged as a mainstream mode of transportation in China, owing to their exceptional safety and efficiency. Ensuring the reliable operation of HSTs is of paramount economic and societal importance. As critical rotating mechanical components of the transmission system, bearings make their fault diagnosis a topic of extensive attention. This paper provides a systematic review of image encoding-based bearing fault diagnosis methods tailored to the condition monitoring of HSTs. First, it categorizes the image encoding techniques applied in the field of bearing fault diagnosis. Then, a review of state-of-the-art studies has been presented, encompassing both monomodal image conversion and multimodal image fusion approaches. Finally, it highlights current challenges and proposes future research directions to advance intelligent fault diagnosis in HSTs, aiming to provide a valuable reference for researchers and engineers in the field of intelligent operation and maintenance. 展开更多
关键词 High-speed trains Image encoding Fault diagnosis Rotating machinery Condition monitoring
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Validity of the Gaussian phase distribution approximation for analysis of isotropic diffusion encoding applied to restricted diffusion in a cylinder
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作者 Daniel Topgaard 《Magnetic Resonance Letters》 2025年第4期20-27,共8页
The Gaussian phase distribution approximation enables analysis of restricted diffusion encoded by general gradient waveforms but fails to account for the diffraction-like features that may occur for simple pore geomet... The Gaussian phase distribution approximation enables analysis of restricted diffusion encoded by general gradient waveforms but fails to account for the diffraction-like features that may occur for simple pore geometries.We investigate the range of validity of the approximation by random walk simulations of restricted diffusion in a cylinder using isotropic diffusion encoding sequences as well as conventional single gradient pulse pairs and oscillating gradient waveforms.The results show that clear deviations from the approximation may be observed at relative signal attenuations below 0.1 for onedimensional sequences with few oscillation periods.Increasing the encoding dimensionality and/or number of oscillations while extending the total duration of the waveform diminishes the non-Gaussian effects while preserving the low apparent diffusivities characteristic of restriction. 展开更多
关键词 NMR DIFFUSION Porous media Pulsed gradient spin echo Tensor-valued encoding
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Autonomous inverse encoding guides 4D nanoprinting for highly programmable shape morphing
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作者 Shuaiqi Ren Zhiang Zhang +6 位作者 Ruokun He Jiahao Fan Guangming Wang Hesheng Wang Bing Han Yong-Lai Zhang Zhuo-Chen Ma 《International Journal of Extreme Manufacturing》 2025年第3期467-482,共16页
Highly programmable shape morphing of 4D-printed micro/nanostructures is urgently desired for applications in robotics and intelligent systems.However,due to the lack of autonomous holistic strategies throughout the t... Highly programmable shape morphing of 4D-printed micro/nanostructures is urgently desired for applications in robotics and intelligent systems.However,due to the lack of autonomous holistic strategies throughout the target shape input,optimal material distribution generation,and fabrication program output,4D nanoprinting that permits arbitrary shape morphing remains a challenging task for manual design.In this study,we report an autonomous inverse encoding strategy to decipher the genetic code for material property distributions that can guide the encoded modeling toward arbitrarily pre-programmed 4D shape morphing.By tuning the laser power of each voxel at the nanoscale,the genetic code can be spatially programmed and controllable shape morphing can be realized through the inverse encoding process.Using this strategy,the 4D-printed structures can be designed and accurately shift to the target morphing of arbitrarily hand-drawn lines under stimulation.Furthermore,as a proof-of-concept,a flexible fiber micromanipulator that can approach the target region through pre-programmed shape morphing is autonomously inversely encoded according to the localized spatial environment.This strategy may contribute to the modeling and arbitrary shape morphing of micro/nanostructures fabricated via 4D nanoprinting,leading to cutting-edge applications in microfluidics,micro-robotics,minimally invasive robotic surgery,and tissue engineering. 展开更多
关键词 femtosecond laser fabrication 4D printing two-photon polymerization autonomous inverse encoding stimuli-responsive materials
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Enhancing the genomic prediction accuracy of swine agricultural economic traits using an expanded one-hot encoding in CNN models
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作者 Zishuai Wang Wangchang Li Zhonglin Tang 《Journal of Integrative Agriculture》 2025年第9期3574-3582,共9页
Deep learning(DL)methods like multilayer perceptrons(MLPs)and convolutional neural networks(CNNs)have been applied to predict the complex traits in animal and plant breeding.However,improving the genomic prediction ac... Deep learning(DL)methods like multilayer perceptrons(MLPs)and convolutional neural networks(CNNs)have been applied to predict the complex traits in animal and plant breeding.However,improving the genomic prediction accuracy still presents signifcant challenges.In this study,we applied CNNs to predict swine traits using previously published data.Specifcally,we extensively evaluated the CNN model's performance by employing various sets of single nucleotide polymorphisms(SNPs)and concluded that the CNN model achieved optimal performance when utilizing SNP sets comprising 1,000 SNPs.Furthermore,we adopted a novel approach using the one-hot encoding method that transforms the 16 different genotypes into sets of eight binary variables.This innovative encoding method signifcantly enhanced the CNN's prediction accuracy for swine traits,outperforming the traditional one-hot encoding techniques.Our fndings suggest that the expanded one-hot encoding method can improve the accuracy of DL methods in the genomic prediction of swine agricultural economic traits.This discovery has significant implications for swine breeding programs,where genomic prediction is pivotal in improving breeding strategies.Furthermore,future research endeavors can explore additional enhancements to DL methods by incorporating advanced data pre-processing techniques. 展开更多
关键词 SWINE agricultural economic traits genomic prediction deep learning one-hot encoding convolutional neural networks(CNNs)
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Improved Sensitivity Encoding Parallel Magnetic Resonance Imaging Reconstruction Algorithm Based on Efficient Sum of Outer Products Dictionary Learning
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作者 DUAN Jizhong SU Yan 《Journal of Shanghai Jiaotong university(Science)》 2025年第3期561-571,共11页
Sensitivity encoding(SENSE)is a parallel magnetic resonance imaging(MRI)reconstruction model by utilizing the sensitivity information of receiver coils to achieve image reconstruction.The existing SENSE-based reconstr... Sensitivity encoding(SENSE)is a parallel magnetic resonance imaging(MRI)reconstruction model by utilizing the sensitivity information of receiver coils to achieve image reconstruction.The existing SENSE-based reconstruction algorithms usually used nonadaptive sparsifying transforms,resulting in a limited reconstruction accuracy.Therefore,we proposed a new model for accurate parallel MRI reconstruction by combining the L0 norm regularization term based on the efficient sum of outer products dictionary learning(SOUPDIL)with the SENSE model,called SOUPDIL-SENSE.The SOUPDIL-SENSE model is mainly solved by utilizing the variable splitting and alternating direction method of multipliers techniques.The experimental results on four human datasets show that the proposed algorithm effectively promotes the image sparsity,eliminates the noise and artifacts of the reconstructed images,and improves the reconstruction accuracy. 展开更多
关键词 parallel magnetic resonance imaging(MRI) sensitivity encoding(SENSE) efficient sum of outer products dictionary learning(SOUPDIL) alternating direction method of multipliers
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基于双向时序窗口Transformer的网络入侵检测方法
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作者 王长浩 王明阳 +1 位作者 丁磊 刘凯 《计算机应用研究》 北大核心 2026年第1期271-279,共9页
近年来,网络攻击的高度动态化、隐蔽化给互联网的安全和稳定带来了极大的威胁。针对现有网络入侵检测方法在局部时序建模精度不足及多分类下少数类识别能力不佳等问题,提出了一种基于双向时间滑动窗口Transformer的网络异常流量检测方... 近年来,网络攻击的高度动态化、隐蔽化给互联网的安全和稳定带来了极大的威胁。针对现有网络入侵检测方法在局部时序建模精度不足及多分类下少数类识别能力不佳等问题,提出了一种基于双向时间滑动窗口Transformer的网络异常流量检测方法。该方法将网络流量数据转换为突出时序关系的三维序列数据,引入可学习的嵌入编码及上下文位置编码,以增强序列特征的表现能力,提升了异常流量检测的准确率和稳定性,并在UNSW-NB15、CIC-IDS-2017公开数据集上进行了验证。实验结果表明,所提方法均表现出较好的性能优势,在二分类任务中检测准确率分别为99.79%、99.77%;在多分类任务中,准确率分别达到98.48%、99.76%,性能均显著高于其他先进深度学习模型。综上,该方法有效提升了网络异常流量检测的准确性和对少数类攻击的识别能力,为网络安全防护提供了新的技术手段。 展开更多
关键词 入侵检测 网络流量 双向时间窗口 上下文位置编码
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基于多方位感知深度融合检测头的目标检测算法
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作者 包晓安 彭书友 +3 位作者 张娜 涂小妹 张庆琪 吴彪 《浙江大学学报(工学版)》 北大核心 2026年第1期32-42,共11页
针对传统目标检测头难以有效捕捉全局信息的问题,提出基于多方位感知深度融合检测头的目标检测算法.通过在检测头部分设计高效双轴窗口注意力编码器(EDWE)模块,使网络能够深度融合捕获到的全局信息与局部信息;在特征金字塔结构之后使用... 针对传统目标检测头难以有效捕捉全局信息的问题,提出基于多方位感知深度融合检测头的目标检测算法.通过在检测头部分设计高效双轴窗口注意力编码器(EDWE)模块,使网络能够深度融合捕获到的全局信息与局部信息;在特征金字塔结构之后使用重参化大核卷积(RLK)模块,减小来自主干网络的特征空间差异,增强网络对中小型数据集的适应性;引入编码器选择保留模块(ESM),选择性地累积来自EDWE模块的输出,优化反向传播.实验结果表明,在规模较大的MS-COCO2017数据集上,所提算法应用于常见模型RetinaNet、FCOS、ATSS时使AP分别提升了2.9、2.6、3.4个百分点;在规模较小的PASCAL VOC2007数据集上,所提算法使3种模型的AP分别实现了1.3、1.0和1.1个百分点的提升.通过EDWE、RLK和ESM模块的协同作用,所提算法有效提升了目标检测精度,在不同规模的数据集上均展现了显著的性能优势. 展开更多
关键词 检测头 目标检测 Transformer编码器 深度融合 大核卷积
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基于文本引导的轻量异构编码多模态图像融合
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作者 王传云 周明奇 +3 位作者 孙冬冬 王田 高骞 李照奎 《工程科学学报》 北大核心 2026年第2期346-359,共14页
针对资源受限的无人机平台对红外与可见光图像的融合效率与感知性能需求,本文提出一种基于文本引导的轻量异构编码多模态图像融合网络.该网络设计了一种面向红外与可见光图像信息表达功能互补的轻量化双分支异构编码,红外图像编码分支... 针对资源受限的无人机平台对红外与可见光图像的融合效率与感知性能需求,本文提出一种基于文本引导的轻量异构编码多模态图像融合网络.该网络设计了一种面向红外与可见光图像信息表达功能互补的轻量化双分支异构编码,红外图像编码分支强调热目标与边缘响应,可见光图像编码分支侧重于纹理与细节信息建模,从而有效避免同构编码器带来的特征冗余与性能瓶颈.同时,引入轻量级跨模态特征融合模块,增强多模信息之间的互补性与融合表达能力.进一步,通过预训练视觉语言模型结合语义文本特征对融合过程进行引导与调控,提升融合图像的语义一致性与环境适应性.在三个公开多模态图像数据集TNO、LLVIP与M3FD上,本文方法与九种代表性图像融合算法进行了系统对比实验与综合评估,结果显示本文网络在互信息、结构相似性等多个主流评价指标上均表现优越,融合图像在细节清晰度、边缘结构一致性与目标可辨性方面优于现有方法.同时,消融实验表明所提出模型的推理时间相较基线方法减少约50%,且在不显著牺牲性能的前提下实现了更高的效率.除定量评估外,本文还开展了基于文本指令的定性实验,结果显示模型可根据不同语义指令灵活调整红外与可见光特征融合策略,适应低光、过曝、低对比、噪声等多种任务场景.在保证语义一致性的同时,有效增强了热源感知、结构清晰度与抗干扰能力,展现出传统无引导方法难以实现的语义可控性与内容适应性. 展开更多
关键词 多模态图像融合 双分支异构编码 文本引导 轻量化网络 注意力机制
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基于线性注意和类别关联特征学习的在线动作检测
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作者 詹永照 孙慧敏 +1 位作者 夏惠芬 任晓鹏 《江苏大学学报(自然科学版)》 北大核心 2026年第1期39-47,63,共10页
为了在在线动作检测中充分合理利用动作的上下文特征、与类别关联的特征和预测的未来特征快速检测相应动作,提出基于线性注意和类别关联特征学习的在线动作检测方法.该方法改进了Transformer构架,采用哈达玛积的轻型线性自注意实现Trans... 为了在在线动作检测中充分合理利用动作的上下文特征、与类别关联的特征和预测的未来特征快速检测相应动作,提出基于线性注意和类别关联特征学习的在线动作检测方法.该方法改进了Transformer构架,采用哈达玛积的轻型线性自注意实现Transformer视频上下文特征学习,以减少计算开销;其次对训练样本动作特征进行聚类,将视频序列上下文特征与动作类别特征进行关联学习,有效获得与类别关联的特征表达;最后融合动作的上下文特征、与类别关联的特征和预测的未来特征检测相应时刻动作,以提升动作鉴别性.在典型数据集上进行性能试验,完成了超参取值分析,对比了不同方法的工作精度和运行效率.给出了消融试验和可视化分析.结果表明:在Thumos14(TSN-Anet)、Thumos14(TSN-Kinetics)和HDD数据集上,所提出方法的mAP比Colar方法分别提高了0.2、0.5、0.2百分点,可见新方法优于目前较先进的Colar方法. 展开更多
关键词 在线动作检测 深度学习 注意力机制 编码 上下文特征 TRANSFORMER 类别关联特征学习
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基于门控循环单元的局域网络总线入侵智能检测研究
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作者 张国志 《现代电子技术》 北大核心 2026年第2期54-58,共5页
为提高实验室局域网络总线入侵检测的时效性与准确性,设计一种基于门控循环单元的总线入侵智能检测方法。对仅包含两种状态的定性特征进行二值化处理,对包含三种或更多类别的特征,通过one-hot编码将其转换为向量特征;再对数据集进行规... 为提高实验室局域网络总线入侵检测的时效性与准确性,设计一种基于门控循环单元的总线入侵智能检测方法。对仅包含两种状态的定性特征进行二值化处理,对包含三种或更多类别的特征,通过one-hot编码将其转换为向量特征;再对数据集进行规范化调整,平衡不同量级的数据特征。为提高检测上限,使用结合聚类的欠采样算法构建平衡数据集,融合门控循环单元(GRU)与卷积神经网络(CNN)构建CNN-GRU入侵检测模型,以实现局域网络总线入侵的智能、高效检测。实验测试结果表明,在检测不同攻击时,所设计方法的Micro-F_(1)和Macro-F_(1)指标均较高,对于不同攻击的检测耗时均低于0.2 s。 展开更多
关键词 入侵检测 局域网络总线 门控循环单元 卷积神经网络 混合采样 one-hot编码
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基于空间通道自适应特征的肝脏病理图像分割网络
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作者 王建宇 王朝立 +1 位作者 孙占全 刘晓虹 《电子科技》 2026年第1期9-17,共9页
针对肝脏病理图像中病变区域与周围组织相似度高、对比度低以及边界模糊等问题,文中提出了一个基于空间通道自适应特征的肝脏病理分割网络。通过混合校准注意力使网络能够自适应地选择经空间和通道校准过的特征信息,有利于编码器捕获与... 针对肝脏病理图像中病变区域与周围组织相似度高、对比度低以及边界模糊等问题,文中提出了一个基于空间通道自适应特征的肝脏病理分割网络。通过混合校准注意力使网络能够自适应地选择经空间和通道校准过的特征信息,有利于编码器捕获与肝脏病灶相关的重要特征,并在编码器最深层引入空洞空间金字塔池化模块来弥补高级特征所缺失的多尺度信息,提高模型的分割精度。在私有肝脏数据集、公开肝脏数据集以及其他两种公开病理数据集对所提网络进行对比实验和消融实验。实验结果表明,相较于其他方法,所提网络的分割结果较佳,且有效解决了肝细胞癌分割问题。 展开更多
关键词 肝细胞癌 病理图像 编解码架构 混合校准注意力模块 空间注意力 通道注意力 空洞空间金字塔池化模块 多尺度信息
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Continuous Pseudocolor Encoding of Thermal Image Display 被引量:6
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作者 李为 《Journal of Beijing Institute of Technology》 EI CAS 1997年第1期37-42,共6页
The visual features of continuous pseudocolor encoding is discussed and the optimiz- ing design algorithm of continuous pseudocolor scale is derived.The algorithm is restricting the varying range and direction of ligh... The visual features of continuous pseudocolor encoding is discussed and the optimiz- ing design algorithm of continuous pseudocolor scale is derived.The algorithm is restricting the varying range and direction of lightness,hue and saturation according to correlation and naturalness,automatically calculating the chromaticity coordinates of nodes in uniform color space to get the longest length of scale path,then interpolating points between nodes in equal color differences to obtain continuous pseudocolor scale with visual uniformity.When it was applied to the pseudocolor encoding of thermal image displays,the results showed that the correlation and the naturalness of original images and cognitive characteristics of target pattern were reserved well;the dynamic range of visual perception and the amount of visual information increased obviously;the contrast sensitivity of target identification improved;and the blindness of scale design were avoided. 展开更多
关键词 thermal image display pseudocolor encoding OPTIMIZATION color vision
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基于Filter Encoding的GML空间数据查询 被引量:3
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作者 苗立志 张书亮 +2 位作者 伍蓝 闾国年 焦东来 《计算机工程》 CAS CSCD 北大核心 2008年第3期59-61,共3页
随着地理数据网络化程度的提高和GML空间数据的应用越来越广泛,如何从海量的GML空间数据中检索出符合特定条件的地理要素数据成为目前GML研究的焦点问题之一。该文根据OGC制定的过滤编码执行规程,应用规程中的谓词作为查询关键字,结合GM... 随着地理数据网络化程度的提高和GML空间数据的应用越来越广泛,如何从海量的GML空间数据中检索出符合特定条件的地理要素数据成为目前GML研究的焦点问题之一。该文根据OGC制定的过滤编码执行规程,应用规程中的谓词作为查询关键字,结合GML空间数据的特点,通过查询转译器和优化器实现了一种应用于GML空间数据查询的可行性方法。 展开更多
关键词 查询转译器 查询优化器 过滤编码
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Delay and Energy Efficient Design of an On-Chip Bus with Repeaters Using a New Spatial and Temporal Encoding Technique
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作者 张庆利 王进祥 +1 位作者 喻明艳 叶以正 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第4期724-732,共9页
On-chip global buses in deep sub-micron designs consume significant amounts of energy and have large propagation delays. Thus, minimizing energy dissipation and propagation delay is an important design objective. In t... On-chip global buses in deep sub-micron designs consume significant amounts of energy and have large propagation delays. Thus, minimizing energy dissipation and propagation delay is an important design objective. In this paper, we propose a new spatial and temporal encoding approach for generic on-chip global buses with repeaters that enables higher performance while reducing peak energy and average energy. The proposed encoding approach exploits the benefits of a temporal encoding circuit and spatial bus-invert coding techniques to simultaneously eliminate opposite transitions on adjacent wires and reduce the number of self-transitions and coupling-transitions. In the design process of applying encoding techniques for reduced bus delay and energy, we present a repeater insertion design methodology to determine the repeater size and inter-repeater bus length, which minimizes the total bus energy dissipation while satisfying target delay and slew-rate constraints. This methodology is employed to obtain optimal energy versus delay trade-offs under slew-rate constraints for various encoding techniques. 展开更多
关键词 on-chip buses DELAY energy encoding REPEATERS
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Parallel Distributed CFAR Detection Optimization Based on Genetic Algorithm with Interval Encoding
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作者 于泽 周荫清 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2010年第3期351-358,共8页
Aiming at parallel distributed constant false alarm rate (CFAR) detection employing K/N fusion rule,an optimization algorithm based on the genetic algorithm with interval encoding is proposed. N-1 local probabilitie... Aiming at parallel distributed constant false alarm rate (CFAR) detection employing K/N fusion rule,an optimization algorithm based on the genetic algorithm with interval encoding is proposed. N-1 local probabilities of false alarm are selected as optimization variables. And the encoding intervals for local false alarm probabilities are sequentially designed by the person-by-person optimization technique according to the constraints. By turning constrained optimization to unconstrained optimization,the problem of increasing iteration times due to the punishment technique frequently adopted in the genetic algorithm is thus overcome. Then this optimization scheme is applied to spacebased synthetic aperture radar (SAR) multi-angle collaborative detection,in which the nominal factor for each local detector is determined. The scheme is verified with simulations of cases including two,three and four independent SAR systems. Besides,detection performances with varying K and N are compared and analyzed. 展开更多
关键词 parallel processing systems synthetic aperture radar detectors genetic algorithms OPTIMIZATION encoding
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基于时序数据库的棒线材连轧过程数据编码优化
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作者 张东 李铁 《控制工程》 北大核心 2026年第1期49-56,共8页
为了提升高频时序数据的存储效率和提取性能,结合应用数据的特点和时序数据库(time series database,TSDB)的编码方法,对棒线材连轧过程数据编码进行了联合优化。首先,为了优化应用端,针对棒线材连轧过程数据的结构特点和应用特点,建立... 为了提升高频时序数据的存储效率和提取性能,结合应用数据的特点和时序数据库(time series database,TSDB)的编码方法,对棒线材连轧过程数据编码进行了联合优化。首先,为了优化应用端,针对棒线材连轧过程数据的结构特点和应用特点,建立了基于工作模式的复合信源模型;然后,为了优化TSDB端,针对在InfluxDB存储复合信源数据时定长划分数据块引起的时间戳编码冗余问题,提出了基于变长数据块的编码优化方法;最后,为了保证优化后系统的稳定性,提出了重写时间结构合并树(time-structured merge-tree,TSM)文件的非源码改造方案。使用实际轧机的棒材连轧过程数据进行测试,测试结果表明,经过编码优化后,TSM文件的总编码长度和时间戳的编码长度分别降低了37.6%和91.3%,所提方法不仅提升了数据存储效率,而且大幅度提高了数据提取性能。 展开更多
关键词 棒线材 InfluxDB 编码优化 时序数据 复合信源
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