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Embedded RF fingerprint interpretation:multi-channel complex residual networks with adaptive sphere space decision boundaries
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作者 DUAN Yongsheng ZHANG Junning +1 位作者 XUE Lei XU Ying 《Journal of Systems Engineering and Electronics》 2026年第1期137-147,共11页
Despite the superior advantages of specific emitter identification in extracting emitter features from in-phase and quadrature(I/Q)signals,challenges persist due to signal-type confusion and background noise interfere... Despite the superior advantages of specific emitter identification in extracting emitter features from in-phase and quadrature(I/Q)signals,challenges persist due to signal-type confusion and background noise interference.To address those limitations,this paper proposes a multi-channel contrast prediction coding and complex-valued residuals network(MCPC-MCVResNet)framework.This model employs contrast prediction techniques to directly extract discriminative features from electromagnetic signal sequences,effectively capturing both amplitude and phase information within I/Q data.A core innovation of this approach is the sphere space softmax(SS-softmax)loss,which optimizes intra-class clustering density of while establishing well-defined boundaries between distinct emitters.The SS-softmax mechanism significantly enhances the model's capacity to discern subtle variations among radiation emitters.Experimental results demonstrate superior identification accuracy,rapid convergence,and exceptional robustness in low signal-to-noise ratio environments. 展开更多
关键词 specific emitter identification(SEI) multi-channel complex-valued residual network(MCVResNet) sphere spacesoftmax(SS-softmax)
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Dynamic terahertz multi-channel beam steering with dual-frequency multiplexing based on magneto-optical metasurfaces
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作者 Dan Zhao Fei Fan +5 位作者 Hao Wang Pengxuan Li Zhen Xu Jining Li Yunyun Ji Shengjiang Chang 《Advanced Photonics Nexus》 2025年第3期149-157,共9页
With the urgently increasing demand for high-speed and large-capacity communication trans-mission,there remains a critical need for tunable terahertz(THz)devices with multi-channel in 5G/6G communication systems.A mag... With the urgently increasing demand for high-speed and large-capacity communication trans-mission,there remains a critical need for tunable terahertz(THz)devices with multi-channel in 5G/6G communication systems.A magnetic phase-coding meta-atom(MPM)is formed by the heterogeneous integration of La:YIG magneto-optical(MO)materials and Si microstructures.The MPM couples the magnetic induction phase of spin states with the propagation phase and can simultaneously satisfy the required output phase for dual frequencies under various external magnetic fields to realize the dynamic beam steering among multiple channels at 0.25 and 0.5 THz.The energy ratio of the target direction can reach 96.5%,and the nonreciprocal one-way transmission with a max isolation of 29.8 dB is realized due to the nonreciprocal phase shift of the MO layer.This nonreciprocal mechanism of magnetic induction reshaping of wavefront significantly holds promise for advancing integrated multi-functional THz devices with the characteristics of low-crosstalk,multi-channel,and multi-frequency,and has great potential to promote the development of THz large-capacity and high-speed communication. 展开更多
关键词 TERAHERTZ multi-channel DUAL-FREQUENCY nonreciprocal transmission beam steering dynamics
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Terahertz active multi-channel vortices with parity symmetry breaking and near/far field multiplexing based on a dielectric-liquid crystal-plasmonic metadevice
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作者 Yiming Wang Fei Fan +3 位作者 Huijun Zhao Yunyun Ji Jing Liu Shengjiang Chang 《Opto-Electronic Advances》 2025年第5期48-58,共11页
Vortex beams carrying orbital angular momentum(OAM)are of great significance for high-capacity communication and super-resolution imaging.However,there is a huge gap between the free-space vortices(FVs)and plasmonic v... Vortex beams carrying orbital angular momentum(OAM)are of great significance for high-capacity communication and super-resolution imaging.However,there is a huge gap between the free-space vortices(FVs)and plasmonic vortices(PVs)on chips,and active manipulation as well as multiplexing in more channels have become a pressing demand.In this work,we demonstrate a terahertz(THz)cascaded metadevice composed of a helical plasmonic metasurface,a liquid crystal(LC)layer,and a helical dielectric metasurface.By spin-orbital angular momentum coupling and photon state superposition,PVs and FVs are generated with mode purity of over 85%on average.Due to the inversion asymmetric design of the helical metasurfaces,the parity symmetry breaking of OAM is realized(the topological charge numbers no longer occur in positive and negative pairs,but all are positive),generating 6 independent channels associated with the decoupled spin states and the near-/far-field positions.Moreover,by the LC integration,dynamic mode switching and energy distribution can be realized,finally obtaining up to 12 modes with a modulation ratio of above 70%.This active tuning and multi-channel multiplexing metadevice establishes a bridge connection between the PVs and FVs,exhibiting promising applications in THz communication,intelligent perception,and information processing. 展开更多
关键词 TERAHERTZ optical vortex plasmonic metasurface near/far field multi-channel liquid crystal
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Multi-Channel Electrolyte Supply for Electrochemical Trepanning of Blisks Using Rotational Feeding Combined with Shift Feeding
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作者 Gaopan Lei Dong Zhu +3 位作者 Mingzhu Ren Erhao Jiao Yongquan Xie Mingfu Li 《Chinese Journal of Mechanical Engineering》 2025年第2期440-458,共19页
Rotational feeding combined with shift feeding electrochemical trepanning(RF-SF ECTr)is an effective method for machining aeroengine blisks.However,given the variable relative motion of the electrodes and the complex ... Rotational feeding combined with shift feeding electrochemical trepanning(RF-SF ECTr)is an effective method for machining aeroengine blisks.However,given the variable relative motion of the electrodes and the complex flow channels around the bending and twisting blades,the accessibility and uniformity of the flow field are poor in blisk RF-SF ECTr using the traditional electrolyte supply(TES)mode,resulting in poor machining stability and low machining efficiency.To improve the distribution of the flow field,a new multi-channel electrolyte supply(MCES)mode is proposed for blisk RF-SF ECTr,in which the position and volume of the electrolyte supply are controlled effectively by setting multiple inlet channels in the liquid inlet area.A flow-field simulation comparison between TES and MCES shows that better accessibility and uniformity of the flow-field distribution are achieved under MCES.To clarify further the flow-field distribution characteristics under RF-SF ECTr,a series of flow-field simulations was conducted at different machining depths.Based on the obtained dynamic change law for the flow field,to enhance further its uniformity and accessibility,a global coverage strategy for the electrolyte supply and a flow-field structure optimization method for MCES are proposed,which involve optimizing the number,diameter,and location of the inlet channels.After many simulations,the optimal MCES structure was achieved whereby the electrolyte covers all positions effectively in the processing area.To verify the proposed method as effective and correct,a series of RF-SF ECTr experiments was carried out.Under the optimized MCES mode,the feeding rate was increased from 0.8 mm/min with the TES mode to 2.0 mm/min,and the processing stability and efficiency were improved significantly.The methods presented here offer an effective guide for flow-field optimization when machining other components with complex spatial structures. 展开更多
关键词 Electrochemical trepanning Blisk Rotational feeding Flow field optimization multi-channel electrolyte supply
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Analysis of the effect of multi-channel continuous nursing intervention on patients post-radical gastrectomy
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作者 Huan-Li Luo Huan-Ling Luo 《World Journal of Gastrointestinal Surgery》 2025年第4期110-119,共10页
BACKGROUND Radical gastrectomy(RGE)for gastric carcinoma(GC)has exerted definite therapeutic efficacy in treating patients with GC.However,a notable risk of postoperative complications(POCs)persists among middle-aged ... BACKGROUND Radical gastrectomy(RGE)for gastric carcinoma(GC)has exerted definite therapeutic efficacy in treating patients with GC.However,a notable risk of postoperative complications(POCs)persists among middle-aged and elderly patients with compromised physiological functions.Hence,developing and implementing reliable nursing interventions to optimize the comprehensive management of these patients is deemed imperative.AIM To analyze the association of multi-channel continuous nursing intervention with POCs,negative emotions(NEs),and quality of life(QoL)of patients undergoing RGE for GC.METHODS This retrospective study selected 99 patients who underwent RGE for GC in our hospital from May 2020 to May 2023.Participants were categorized into the control(n=49 cases)and research groups(n=50 cases)receiving routine and multi-channel continuous nursing care,respectively.Comparative analysis involved data on postoperative rehabilitation(time to first anal exhaust,oral feeding and ambulation,and hospital stay),complications(nausea and vomiting,delayed gastric emptying,and abdominal distension),NEs[Self-rating Anxiety(SAS)/Depression Scale(SDS)],treatment compliance,self-efficacy,and QoL[World Health Organization QoL Brief Version(WHOQOL-BREF)].RESULTS Compared to the control group,the research group demonstrated earlier first postoperative anal exhaust,oral feeding,and ambulation,shorter hospital stay,lower POC rate,and more reduced SAS and SDS scores postintervention,which was significantly lower than the baseline.The treatment compliance scores were significantly higher in the research group than in the control group in terms of medication adherence,daily exercise,reasonable diet,and regular review.Further,the research group demonstrated increased self-efficacy scores in terms of positive attitude,self-stress relief,and self-decision-making,as well as the overall score postintervention,which were higher than the control group.Moreover,the research group reported notably higher WHOQOL-BREF scores in domains such as physiology,psychology,social relations,and environment.CONCLUSION Multi-channel continuous nursing intervention prevents POCs in patients undergoing RGE for GC as well as significantly alleviates patients’NEs and boosts their QoL. 展开更多
关键词 Radical gastrectomy multi-channel continuous nursing Postoperative complications Negative emotions Quality of life
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AMSA:Adaptive Multi-Channel Image Sentiment Analysis Network with Focal Loss
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作者 Xiaofang Jin Yiran Li Yuying Yang 《Computers, Materials & Continua》 2025年第12期5309-5326,共18页
Given the importance of sentiment analysis in diverse environments,various methods are used for image sentiment analysis,including contextual sentiment analysis that utilizes character and scene relationships.However,... Given the importance of sentiment analysis in diverse environments,various methods are used for image sentiment analysis,including contextual sentiment analysis that utilizes character and scene relationships.However,most existing works employ character faces in conjunction with context,yet lack the capacity to analyze the emotions of characters in unconstrained environments,such as when their faces are obscured or blurred.Accordingly,this article presents the Adaptive Multi-Channel Sentiment Analysis Network(AMSA),a contextual image sentiment analysis framework,which consists of three channels:body,face,and context.AMSA employs Multi-task Cascaded Convolutional Networks(MTCNN)to detect faces within body frames;if detected,facial features are extracted and fused with body and context information for emotion recognition.If not,the model leverages body and context features alone.Meanwhile,to address class imbalance in the EMOTIC dataset,Focal Loss is introduced to improve classification performance,especially for minority emotion categories.Experimental results have shown that certain sentiment categories with lower representation in the dataset demonstrate leading classification accuracy,the AMSA yields a 2.53%increase compared with state-of-the-art methods. 展开更多
关键词 Image sentiment analysis adaptive multi-channel class imbalance
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基于多通道耦合的时空增强异常行为检测
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作者 章东平 潘鑫 +2 位作者 马道滨 米红妹 林丽莉 《北京航空航天大学学报》 北大核心 2026年第1期73-79,共7页
针对现有异常行为检测模型在特征提取方面存在局限、对动态时序特征建模不足的问题,提出一种基于多通道耦合的时空增强异常行为检测方法。该方法以SlowFast网络为基础,在慢路径中引入多通道耦合的空间增强模块以强化静态特征建模,在快... 针对现有异常行为检测模型在特征提取方面存在局限、对动态时序特征建模不足的问题,提出一种基于多通道耦合的时空增强异常行为检测方法。该方法以SlowFast网络为基础,在慢路径中引入多通道耦合的空间增强模块以强化静态特征建模,在快路径中引入多通道耦合的时间增强模块以提升动态时序特征的判别能力。在Violent Flow、Hockey Fight和Real-life Violence Situations 3个基准数据集上的实验表明,所提方法的预测准确率分别达到95.3%、97.3%和94%,优于现有主流方法。结果验证了所提方法在异常行为检测任务中具有更强的特征表达能力和泛化性能。 展开更多
关键词 SlowFast 时空增强 异常行为检测 多通道耦合 注意力机制
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基于FreeRTOS的检测仪通道扩展系统设计
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作者 唐俊 王喆 +1 位作者 徐立浩 张心静 《工业控制计算机》 2026年第2期39-40,43,共3页
针对传统单通道或少通道检测仪暴露出的局限性,提出基于FreeRTOS的检测仪通道扩展系统设计。软件方面,相较于裸机,FreeRTOS拥有更好的实时性,配合链表存储结构,提高效率;硬件方面选用继电器矩阵实现测试仪与测试通道间的切换。通过软件... 针对传统单通道或少通道检测仪暴露出的局限性,提出基于FreeRTOS的检测仪通道扩展系统设计。软件方面,相较于裸机,FreeRTOS拥有更好的实时性,配合链表存储结构,提高效率;硬件方面选用继电器矩阵实现测试仪与测试通道间的切换。通过软件与硬件的结合,实现对不同通道数产品的检测需求,不需对原测试仪和被测品进行过多修改。实验验证结果表明该设计具有较高的可靠性与稳定性。 展开更多
关键词 FREERTOS 链表存储 多通道
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HM-YOLO:融合多尺度特征的轻量化航拍图像检测算法
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作者 李珺 丁彬彬 +1 位作者 史维娟 杨琳 《计算机工程与应用》 北大核心 2026年第1期87-100,共14页
针对无人机航拍图像检测任务中,存在目标尺寸微小、背景环境复杂和特征提取困难等问题,在YOLOv11的基础上提出了一种轻量化的航拍图像检测算法HM-YOLO。对骨干网络中不同尺度的特征进行下采样和上采样,扩展了不同特征通道之间的信息交互... 针对无人机航拍图像检测任务中,存在目标尺寸微小、背景环境复杂和特征提取困难等问题,在YOLOv11的基础上提出了一种轻量化的航拍图像检测算法HM-YOLO。对骨干网络中不同尺度的特征进行下采样和上采样,扩展了不同特征通道之间的信息交互,同时优化了浅层特征图的大小以适应航拍图像中的微小目标;设计了高效特征提取模块C3k2_MSEE,先利用自适应平均池化对特征图进行划分,再通过边缘增强模块来突出边缘信息,避免小目标特征信息在深层网络中丢失;提出了层次注意力融合模块HAFB,通过构建局部与全局双路注意力网络,强化了模型对上下文信息的整合能力;引入了具有多重注意力机制的动态检测头DyHead,进一步优化了对小目标特征信息的感知能力。并且使用LAMP剪枝方法和BCKD知识蒸馏策略对HM-YOLO进行了轻量化处理,显著压缩了模型的体积。在Visdrone2019数据集上的实验结果表明,改进后算法的准确率、召回率和mAP@50,分别提升了8.4、5.7和8.4个百分点,能够有效应对无人机航拍图像目标检测任务中的挑战。 展开更多
关键词 YOLOv11 小目标检测 多尺度特征 通道剪枝 知识蒸馏 轻量化
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对比学习引导的双通道自适应融合网络多视图聚类方法
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作者 周丽娟 刘子源 +1 位作者 许鑫航 张志鸿 《小型微型计算机系统》 北大核心 2026年第1期229-239,共11页
近年来,图卷积网络在多视图聚类中表现突出,但其侧重节点间结构信息建模,而属性信息仅通过简单的线性变换进行更新,限制了模型对节点属性信息的学习能力.为此,本文提出了对比学习引导的双通道自适应融合网络多视图聚类方法.首先,结合自... 近年来,图卷积网络在多视图聚类中表现突出,但其侧重节点间结构信息建模,而属性信息仅通过简单的线性变换进行更新,限制了模型对节点属性信息的学习能力.为此,本文提出了对比学习引导的双通道自适应融合网络多视图聚类方法.首先,结合自编码器与图自编码器构建双通道网络,分别编码节点属性和结构信息,并设计通道自适应融合模块,利用注意力机制自适应融合不同通道网络在同一神经网络层中学习的属性与结构信息,以及不同神经网络层间的嵌入表示,以获得每个视图的嵌入表示.在此基础上,进一步利用注意力机制对多个视图的嵌入表示进行加权融合获得全局嵌入表示.最后,通过跨视图对比损失与自监督聚类损失迭代优化全局嵌入表示,强化视图间一致性信息学习,并生成了面向聚类任务的高质量嵌入表示.在3个公开数据集和3个来自郑州商品交易所的期货数据集上进行的实验表明,该方法在聚类任务中表现优异. 展开更多
关键词 多视图聚类 自编码器 图自编码器 双通道网络
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Development of multi-channel observation and inversion for IP electrical sounding method 被引量:8
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作者 刘海飞 柳建新 +3 位作者 郭荣文 童孝忠 龚露 彭艳华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期816-823,共8页
In order to improve the exploration effect of deep non-ferrous mineral resources, multi-channel observation methods for induced polarization (IP) electrical sounding data and their inversion imaging technology are s... In order to improve the exploration effect of deep non-ferrous mineral resources, multi-channel observation methods for induced polarization (IP) electrical sounding data and their inversion imaging technology are studied. First of all, four multi-channel observation methods are developed based on conventional IP electrical method, namely three-electrode and four-electrode arrays of unilateral and bilateral current transmitting. Then the maximum smoothness constrained inversion method of the least squares sense for IP electrical sounding data is proposed, and the inversion software is programmed. Finally, the simulation and inversion results of geo-electrical model for the proposed observation methods are analyzed. And the comparison results show that three-electrode array of bilateral current transmitting gives the best result, but the intensity in field work is larger than others; unilateral three-electrode and four-electrode arrays give the better results. Taking detection results and convenience of field exploration work into consideration, these two methods are more suitable for practical application; bilateral observation method of four-electrode array is not suitable for the detection of the steep ore bodies. 展开更多
关键词 IP electrica-1 sounding multi-channel observation deep exploration inversion imaging
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高速嫁接机多路供夹机构试验研究 被引量:1
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作者 李慧文 林承蔚 +4 位作者 杨旭 黄思 初麒 陈治盛 辜松 《农机化研究》 北大核心 2026年第3期78-84,共7页
针对现有嫁接机存在作业生产效率不理想的问题,提出了一种茄果类高速嫁接机嫁接夹多路供夹机构。基于贴接嫁接法使用嫁接夹固定嫁接幼苗的方法,以一体式嫁接夹为研究对象,设计了一种主要由振动盘、精量排夹装置、直线模组、落夹轨道、... 针对现有嫁接机存在作业生产效率不理想的问题,提出了一种茄果类高速嫁接机嫁接夹多路供夹机构。基于贴接嫁接法使用嫁接夹固定嫁接幼苗的方法,以一体式嫁接夹为研究对象,设计了一种主要由振动盘、精量排夹装置、直线模组、落夹轨道、嫁接夹开夹手和对位针等组成的嫁接夹多路供夹机构,在嫁接机一个嫁接作业循环中可同时提供6个嫁接夹,完成6株嫁接苗切口的同时固定。对供夹机构进行了落夹作业性能试验,探究落夹轨道宽度与嫁接夹宽度的相对差、落夹轨道高度与嫁接夹高度的相对差、对位针直径对落夹成功率的影响,结果表明:落夹轨道宽度与嫁接夹宽度的相对差为1 mm、落夹轨道高度与嫁接夹高度的相对差为1.5 mm、对位针直径为1.5 mm时,多路供夹机构的落夹性能最好,落夹成功率可达98%以上,此时多路供夹机构作业效率达3 240个/h,可满足高速嫁接作业的要求。研究结果可为高速嫁接机的研制与开发提供技术参考。 展开更多
关键词 高速嫁接机 嫁接夹 贴接法 供夹机构 多路 轨道
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多通道卷积神经网络预测MOFs对C_(3)F_(6)/C_(3)F_(8)吸附性能
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作者 海广通 郑芳 +6 位作者 陈俐吭 夏伟 盛良正 杨启炜 张治国 鲍宗必 任其龙 《化工学报》 北大核心 2026年第1期459-469,共11页
多孔材料单组分吸附量的准确预测对评估分离性能及指导吸附剂开发至关重要。本文提出多通道卷积神经网络模型,通过特征交叉机制实现金属有机框架材料(MOFs)对C_(3)F_(6)/C_(3)F_(8)吸附量的快速预测。对165844种MOFs进行结构筛选,经高... 多孔材料单组分吸附量的准确预测对评估分离性能及指导吸附剂开发至关重要。本文提出多通道卷积神经网络模型,通过特征交叉机制实现金属有机框架材料(MOFs)对C_(3)F_(6)/C_(3)F_(8)吸附量的快速预测。对165844种MOFs进行结构筛选,经高通量巨正则Monte Carlo(GCMC)模拟获得76438组有效数据。以孔结构及能量描述符为输入,模型仅需2个隐藏层(神经元数分别为8和10)即实现高精度预测(R^(2)≥0.98,MAE≤0.33 mmol·g^(-1))。迁移至CO_(2)体系后保持R^(2)=0.97,验证其优异泛化能力,有望为多孔材料高效筛选提供新工具。 展开更多
关键词 金属有机框架 多通道卷积 神经网络 吸附 计算机模拟
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Design of multi-channel data acquisition system based on LabVIEW and NI PXI-5105 被引量:4
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作者 解亚妮 张志杰 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第1期7-12,共6页
A data acquisition system based on LabVIEW and NI PXI-5105 is presented for multi-channel data acquisition. It can realize the functions of parameter setting, data acquisition and storage, waveform display and data an... A data acquisition system based on LabVIEW and NI PXI-5105 is presented for multi-channel data acquisition. It can realize the functions of parameter setting, data acquisition and storage, waveform display and data analysis using LabVIEW and NI-SCOPE device driver. The advantages of the system are that the setting is convenient, the operation is easy, the interface is friendly and the functions are practical. The experiment results show that the system has good stability and high reliability and is a powerful tool for multi-channel data acquisition. 展开更多
关键词 LABVIEW multi-channel data acquisition PXI-5105
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基于多传感器融合的农业机械轴承半监督故障诊断方法
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作者 李嘉琪 夏尚飞 李东民 《农机化研究》 北大核心 2026年第3期94-102,共9页
针对传统图神经网络只基于单传感器通道建立样本关联图,易受噪声和采集方式的干扰导致样本间关联关系欠缺的问题,提出了基于多传感器融合的农业机械轴承半监督故障诊断方法(MSF-MCGCN)。基于轴承样本的时域、频域特征,采用基于多个传感... 针对传统图神经网络只基于单传感器通道建立样本关联图,易受噪声和采集方式的干扰导致样本间关联关系欠缺的问题,提出了基于多传感器融合的农业机械轴承半监督故障诊断方法(MSF-MCGCN)。基于轴承样本的时域、频域特征,采用基于多个传感器通道的农业机械滚动轴承样本关联图构建方法,从各传感器提取样本之间的关联信息,起到了样本间关联关系互补作用,克服了由于噪声和采集方式的干扰导致单一通道下样本关联关系欠缺的问题;通过多通道图卷积网络完成各传感器特征之间的信息融合,最终得到包含样本间关联信息和多传感器信号的样本特征表示,有效克服了样本间的多通道完备关联关系难以有效融合的问题;在轴承数据集上对MSF-MCGCN方法进行了实验验证,结果表明,MSF-MCGCN在仅使用5%的有标签数据进行训练时,模型诊断准确率达96.19%,为有限样本标签下农业机械轴承的故障诊断提供了新思路。 展开更多
关键词 轴承 故障诊断 多传感器融合 多通道图卷积网络 农业机械运维
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基于微波光子技术的宽带多通道射频前端设计
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作者 高福 张晓玲 +4 位作者 王迪 惠金鑫 李政凯 乔文昇 刘高见 《空间电子技术》 2026年第1期100-107,共8页
跨频段、多通道、可重构射频收发前端是多功能一体化综合射频系统的重要组成部分。为克服传统电子技术的“电子瓶颈”并提升本振泄露抑制能力,本文创新性地提出了一种基于并联型微波光子变频技术与双级微环滤波的跨K-Ka频段多通道射频... 跨频段、多通道、可重构射频收发前端是多功能一体化综合射频系统的重要组成部分。为克服传统电子技术的“电子瓶颈”并提升本振泄露抑制能力,本文创新性地提出了一种基于并联型微波光子变频技术与双级微环滤波的跨K-Ka频段多通道射频前端方案。该方案利用宽范围可调谐光滤波器,在18 GHz~40 GHz范围内实现了工作频率的连续调谐与上下变频功能的灵活切换,并支持四通道射频信号的并行处理。仿真结果表明,相较于单级滤波方案,所提出的双级滤波结构可将本振泄露信号的抑制比提升约15.2 dB。同时,链路仿真获得了约102 dB·Hz^(2/3)以上的无杂散动态范围。本文工作为高性能、可重构射频前端的实现提供了一种有效技术途径。 展开更多
关键词 射频前端 微波光子 跨频段 多通道 可重构
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电阻式半导体气体传感器多通道接口电路设计
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作者 刘东明 韩丹 +3 位作者 王宇轩 段奇 李栋辉 桑胜波 《太原理工大学学报》 北大核心 2026年第1期212-218,共7页
【目的】针对基于纳米材料制备的电阻式半导体气体传感器应用特点,设计了一种原理简单、测量精准、便携性强且适用性广的多通道采样接口电路。【方法】硬件部分以STM32处理器作为主控芯片,采用两级比例运放、挡位切换、ADC采样实现多通... 【目的】针对基于纳米材料制备的电阻式半导体气体传感器应用特点,设计了一种原理简单、测量精准、便携性强且适用性广的多通道采样接口电路。【方法】硬件部分以STM32处理器作为主控芯片,采用两级比例运放、挡位切换、ADC采样实现多通道采集传感器电阻值;软件部分采用加权平均滤波的算法补偿消除物理误差干扰,再与上位机连接实时传输测量数据;通过定值电阻的模拟传感器和实际半导体传感器两种方式进行测试。【结果】电路系统能够精准快速完成对定值电阻和半导体气体传感器的测量,且具有较小的误差,同时设计集成电路可以将传感器封装转化成为可实际测量系统,有效填补了该领域的空白。 展开更多
关键词 气体传感器 多通道 接口电路 加权平均滤波
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基于多通道U-Net的室内电磁波传播路径损耗预测方法
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作者 关策 宋欣蔚 岳云涛 《电波科学学报》 北大核心 2026年第1期79-88,共10页
精准高效的室内电磁波传播预测是无线通信系统规划与优化的关键基础。传统的方法在高频段因电磁波传播特性复杂、计算复杂度剧增,难以满足实时性需求;而现有深度学习模型在高频段适配性与预测精度上也存在一定的局限性。本文提出一种多... 精准高效的室内电磁波传播预测是无线通信系统规划与优化的关键基础。传统的方法在高频段因电磁波传播特性复杂、计算复杂度剧增,难以满足实时性需求;而现有深度学习模型在高频段适配性与预测精度上也存在一定的局限性。本文提出一种多通道U-Net的深度学习预测模型(mU-Net),其将天线方向特性、反射通道贡献、透射通道贡献及自由空间路径损耗(free space path loss, FSPL)分别建模为4个独立特征通道,通过多通道输入U-Net网络捕捉不同传播机制的差异化影响,mU-Net非对称编码器-解码器结构进一步融合多源特征,解析复杂结构散射与绕射细节,从而输出高分辨率路径损耗(path loss, PL)预测图。该模型能深度融合高频段特征信息,解决了现有方法实时性差、精度不足的问题。3种场景下的PL预测结果显示,所提出的mU-Net模型在精度、结构相似性及预测效率等关键指标上均显著优于现有的典型预测方法,在高频段场景下性能提升尤为明显,为高频段室内电磁波传播预测提供了兼具高精度与高效率的解决方案。 展开更多
关键词 室内电磁波传播 路径损耗(PL) 高频段 深度学习 多通道 U-Net
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风电机组试验平台五自由度电液伺服控制系统设计
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作者 王甲 张永明 +1 位作者 陈国初 祝慧林 《轴承》 北大核心 2026年第1期50-57,共8页
风电轴承试验平台电液伺服控制系统通常采用PLC,DSP或成熟的信号采集卡与运动控制卡作为电控系统的核心,当需要控制的液压缸数量较多时会存在液压缸之间协同控制比较困难的问题。提出了一种基于Zynq的电液伺服加载控制系统:采用MKZ801F... 风电轴承试验平台电液伺服控制系统通常采用PLC,DSP或成熟的信号采集卡与运动控制卡作为电控系统的核心,当需要控制的液压缸数量较多时会存在液压缸之间协同控制比较困难的问题。提出了一种基于Zynq的电液伺服加载控制系统:采用MKZ801F.14型伺服阀放大器并设计了基于DAC71408芯片的多通道模数转换单元进行CSDM631型射流管电液伺服阀的驱动,解决了六轴同步驱动控制的问题;采用Block Design的方式设计控制系统,对多通道同步数据采集、多通道驱动信号同步发生单元进行了IP核设计;通过AMESim与Simulink联合仿真验证后,采用基于模型设计的方法进行自动代码生成并设计了API接口以配合多通道模数/数模单元的IP核,实现了复杂控制算法以及载荷模型的快速部署验证。试验结果表明,基于Zynq的电液伺服控制系统能够满足风电轴承试验平台5个自由度的电控要求。 展开更多
关键词 滚动轴承 风力发电机组 伺服控制系统 模型设计 多通道 数模转换
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基于噪声反馈的MVDR-MTGAN多通道语音增强
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作者 王霄雪 刘拓 +1 位作者 江志健 郑能恒 《深圳大学学报(理工版)》 北大核心 2026年第1期93-100,I0003,I0004,共10页
目前主流的多通道语音增强系统大多采用波束形成-后滤波级联架构.在非稳态噪声场景下,波束形成因噪声估计偏差易导致空域滤波失效,而基于深度学习的后滤波虽能改善残留噪声抑制,但计算复杂度高.提出融合最小方差无畸变响应(minimum vari... 目前主流的多通道语音增强系统大多采用波束形成-后滤波级联架构.在非稳态噪声场景下,波束形成因噪声估计偏差易导致空域滤波失效,而基于深度学习的后滤波虽能改善残留噪声抑制,但计算复杂度高.提出融合最小方差无畸变响应(minimum variance distortionless response,MVDR)和多目标生成对抗网络(multi-target generative adversarial network,MTGAN)的闭环增强框架,采用噪声估计反馈机制实现空频域联合优化.通过构建MTGAN的双分支生成器架构同步实现后滤波和噪声估计,并将估计噪声动态反馈至MVDR的协方差矩阵更新过程,形成闭环迭代优化.基于公开的多环境多通道噪声数据集(diverse environments acoustic noise database,DEMAND)的仿真实验表明,噪声反馈机制能有效提升MVDR输出性能;与现有MVDR-CRUSE系统相比,所提MVDR+MTGAN方法保持较低模型复杂度(参数量减少10.5%)的同时,在语音质量评价指标上均获得显著提升,平均分段信噪比提高6.56 dB,整体效果预测得分提升了0.17.该方法为复杂声学场景下的多通道语音增强提供了高效的解决方案. 展开更多
关键词 语音处理 多通道语音增强 最小方差无畸变响应 多目标生成对抗网络 噪声反馈
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