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A review of encapsulation methods and geometric improvements of perovskite solar cells and modules for mass production and commercialization
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作者 Wending Yang Yubo Zhang +2 位作者 Chengchao Xiao Jingxuan Yang Tailong Shi 《Nano Materials Science》 2025年第6期790-809,共20页
Owing to the outstanding optoelectronic properties of perovskite materials,perovskite solar cells(PSCs)have been widely studied by academic organizations and industry corporations,with great potential to become the ne... Owing to the outstanding optoelectronic properties of perovskite materials,perovskite solar cells(PSCs)have been widely studied by academic organizations and industry corporations,with great potential to become the next-generation commercial solar cells.However,critical challenges remain in preserving high efficiency practical large-scale commercialized PSCs:a)the long-term stability of the cell materials and devices,b)lead leakage,and c)methods to scale the cells for larger area applications.This paper summarizes the prior-art strategies to address the above challenges,including the latest studies on the traditional glass-glass and thin-film encapsulation methods to better improve the reliability of PSCs,new technologies for preventing lead leakage,and geometric improvement strategies to enhance the reliability,efficiency,and performance of perovskite solar modules(PSMs).Through these strategies,the device achieved enhanced performance in long-term stability tests.The encapsulation resulted in a high lead leakage inhibition rate of up to 99%,and the PSMs possessed a geometric fill factor of 99.6%and a power conversion efficiency(PCE)of 20.7%.The dramatic improvement of efficiency and reliability of perovskite solar cells and modules indicate the great potential for mass production and commer-cialization of perovskite solar applications in the near future. 展开更多
关键词 Perovskite solar modules ENCAPSULATION Geometric improvement Stability COMMERCIALIZATION
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Single-Channel Speech Enhancement Based on Improved Frame-Iterative Spectral Subtraction in the Modulation Domain 被引量:2
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作者 Chao Li Ting Jiang Sheng Wu 《China Communications》 SCIE CSCD 2021年第9期100-115,共16页
Aiming at the problem of music noise introduced by classical spectral subtraction,a shorttime modulation domain(STM)spectral subtraction method has been successfully applied for singlechannel speech enhancement.Howeve... Aiming at the problem of music noise introduced by classical spectral subtraction,a shorttime modulation domain(STM)spectral subtraction method has been successfully applied for singlechannel speech enhancement.However,due to the inaccurate voice activity detection(VAD),the residual music noise and enhanced performance still need to be further improved,especially in the low signal to noise ratio(SNR)scenarios.To address this issue,an improved frame iterative spectral subtraction in the STM domain(IMModSSub)is proposed.More specifically,with the inter-frame correlation,the noise subtraction is directly applied to handle the noisy signal for each frame in the STM domain.Then,the noisy signal is classified into speech or silence frames based on a predefined threshold of segmented SNR.With these classification results,a corresponding mask function is developed for noisy speech after noise subtraction.Finally,exploiting the increased sparsity of speech signal in the modulation domain,the orthogonal matching pursuit(OMP)technique is employed to the speech frames for improving the speech quality and intelligibility.The effectiveness of the proposed method is evaluated with three types of noise,including white noise,pink noise,and hfchannel noise.The obtained results show that the proposed method outperforms some established baselines at lower SNRs(-5 to +5 dB). 展开更多
关键词 short-time modulation domain single-channel speech enhancement modulation improved frame iterative spectral subtraction low SNRs
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Design of high phase-sensitivity BlueP/TMDC heterostructure-based SPR biosensor using improved artificial bee colony algorithm
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作者 Chong Yue Mantong Chen +1 位作者 Yaopu Lang Qinggang Liu 《Nanotechnology and Precision Engineering》 2025年第2期113-122,共10页
This paper uses an innovative improved artificial bee colony(IABC)algorithm to aid in the fabrication of a highly responsive phasemodulation surface plasmon resonance(SPR)biosensor.In this biosensor’s sensing structu... This paper uses an innovative improved artificial bee colony(IABC)algorithm to aid in the fabrication of a highly responsive phasemodulation surface plasmon resonance(SPR)biosensor.In this biosensor’s sensing structure,a double-layer Ag-Au metal film is combined with a blue phosphorene/transition metal dichalcogenide(BlueP/TMDC)hybrid structure and graphene.In the optimization function of the IABC method,the reflectivity at resonance angle is incorporated as a constraint to achieve high phase sensitivity.The performance of the Ag-Au-BlueP/TMDC-graphene heterostructure as optimized by the IABC method is compared with that of a similar structure optimized using the traditional ABC algorithm.The results indicate that optimization using the IABC method gives significantly more phase sensitivity,together with lower reflectivity,than can be achieved with the traditional ABC method.The highest phase sensitivity of 3.662×10^(6) °/RIU is achieved with a bilayer of BlueP/WS2 and three layers of graphene.Moreover,analysis of the electric field distribution demonstrates that the optimal arrangement can be utilized for enhanced detection of small biomolecules.Thus,given the exceptional sensitivity achieved,the proposed method based on the IABC algorithm has great promise for use in the design of high-performance SPR biosensors with a variety of multilayer structures. 展开更多
关键词 SPR Phase modulation Sensitivity improved artificial bee colony algorithm BlueP/TMDC HETEROSTRUCTURE
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SPD-YOLO:A Method for Detecting Maize Disease Pests Using Improved YOLOv7
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作者 Zhunruo Feng Ruomeng Shi +3 位作者 Yuhan Jiang Yiming Han Zeyang Ma Yuheng Ren 《Computers, Materials & Continua》 2025年第8期3559-3575,共17页
In this study,we propose Space-to-Depth and You Only Look Once Version 7(SPD-YOLOv7),an accurate and efficient method for detecting pests inmaize crops,addressing challenges such as small pest sizes,blurred images,low... In this study,we propose Space-to-Depth and You Only Look Once Version 7(SPD-YOLOv7),an accurate and efficient method for detecting pests inmaize crops,addressing challenges such as small pest sizes,blurred images,low resolution,and significant species variation across different growth stages.To improve the model’s ability to generalize and its robustness,we incorporate target background analysis,data augmentation,and processing techniques like Gaussian noise and brightness adjustment.In target detection,increasing the depth of the neural network can lead to the loss of small target information.To overcome this,we introduce the Space-to-Depth Convolution(SPD-Conv)module into the SPD-YOLOv7 framework,replacing certain convolutional layers in the traditional system backbone and head network.This modification helps retain small target features and location information.Additionally,the Efficient Layer Aggregation Network-Wide(ELAN-W)module is combined with the Convolutional Block Attention Module(CBAM)attention mechanism to extract more efficient features.Experimental results show that the enhanced YOLOv7 model achieves an accuracy of 98.38%,with an average accuracy of 99.4%,outperforming the original YOLOv7 model.These improvements represent an increase of 2.46%in accuracy and 3.19%in average accuracy.The results indicate that the enhanced YOLOv7 model is more efficient and real-time,offering valuable insights for maize pest control. 展开更多
关键词 Deep learning improved YOLOv7 attention mechanism SPD-Conv module insect pest detection
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Solving Job-Shop Scheduling Problem Based on Improved Adaptive Particle Swarm Optimization Algorithm 被引量:3
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作者 顾文斌 唐敦兵 郑堃 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2014年第5期559-567,共9页
An improved adaptive particle swarm optimization(IAPSO)algorithm is presented for solving the minimum makespan problem of job shop scheduling problem(JSP).Inspired by hormone modulation mechanism,an adaptive hormonal ... An improved adaptive particle swarm optimization(IAPSO)algorithm is presented for solving the minimum makespan problem of job shop scheduling problem(JSP).Inspired by hormone modulation mechanism,an adaptive hormonal factor(HF),composed of an adaptive local hormonal factor(H l)and an adaptive global hormonal factor(H g),is devised to strengthen the information connection between particles.Using HF,each particle of the swarm can adjust its position self-adaptively to avoid premature phenomena and reach better solution.The computational results validate the effectiveness and stability of the proposed IAPSO,which can not only find optimal or close-to-optimal solutions but also obtain both better and more stability results than the existing particle swarm optimization(PSO)algorithms. 展开更多
关键词 job-shop scheduling problem(JSP) hormone modulation mechanism improved adaptive particle swarm optimization(IAPSO) algorithm minimum makespan
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Modified Omega-K algorithm for processing helicopter-borne frequency modulated continuous waveform rotating synthetic aperture radar data 被引量:2
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作者 Dong Li Guisheng Liao +1 位作者 Yong Liao Lisheng Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第3期476-485,共10页
With appropriate geometry configuration, helicopter- borne rotating synthetic aperture radar (ROSAR) can break through the limitations of monostatic synthetic aperture radar (SAR) on forward-looking imaging. With ... With appropriate geometry configuration, helicopter- borne rotating synthetic aperture radar (ROSAR) can break through the limitations of monostatic synthetic aperture radar (SAR) on forward-looking imaging. With this capability, ROSAR has extensive potential applications, such as self-navigation and self-landing. Moreover, it has many advantages if combined with the frequency modulated continuous wave (FMCW) technology. A novel geometric configuration and an imaging algorithm for helicopter-borne FMCW-ROSAR are proposed. Firstly, by per- forming the equivalent phase center principle, the separated trans- mitting and receiving antenna system is equalized to the case of system configuration with antenna for both transmitting and receiving signals. Based on this, the accurate two-dimensional spectrum is obtained and the Doppler frequency shift effect in- duced by the continuous motion of the platform during the long pulse duration is compensated. Next, the impacts of the velocity approximation error on the imaging algorithm are analyzed in de- tail, and the system parameters selection and resolution analysis are presented. The well-focused SAR image is then obtained by using the improved Omega-K algorithm incorporating the accurate compensation method for the velocity approximation error. FJnally, correctness of the analysis and effectiveness of the proposed al- gorithm are demonstrated through simulation results. 展开更多
关键词 helicopter-borne rotating synthetic aperture radar(ROSAR) frequency modulated continuous wave (FMCW) improved Omega-K algorithm two-dimensional spectrum.
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Modeling and Analysis of Pulse Skip Modulation 被引量:2
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作者 罗萍 张波 《Journal of Electronic Science and Technology of China》 2006年第1期1-7,共7页
The state space average model and the large signal models of Pulse Skip Modulation (PSM) mode are given in this paper. Farther more, based on these models and simulations of PSM converter circuits, the analysis of t... The state space average model and the large signal models of Pulse Skip Modulation (PSM) mode are given in this paper. Farther more, based on these models and simulations of PSM converter circuits, the analysis of the characteristics of PSM converter is described in this paper, of which include efficiency, frequency spectrum analysis, output voltage ripple, response speed and interference rejection capability. Compared with PWM control mode, PSM converter has high efficiency, especially with fight loads, quick response, good interference rejection and good EMC characteristic. Improved PSM slightly, it could be a kind of good independent regulating mode during the whole operating process for a DC-DC converter. Finally, some experimental results are also presented in this paper. 展开更多
关键词 Pulse Skip modulation (PSM) state space averaged model large signalmodel efficiency Electro Magnetic Interference (EMI) output voltage ripple improved PSM
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A Dual Arm Complementary Hybrid Modulation Strategy Combining NL-SPWM for MMC Applications
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作者 Mingwan Mei Ping Wang +3 位作者 Yanbo Che Zihan Lv Zmarrak Wali Khanand Chao Xing 《Energy Engineering》 EI 2022年第2期591-607,共17页
In the medium voltage direct current(MVDC)transmission system,a small number of MMC sub modules will reduce the power quality.In this paper,based on the research background of Photovoltaic Medium VoltageDirect Current... In the medium voltage direct current(MVDC)transmission system,a small number of MMC sub modules will reduce the power quality.In this paper,based on the research background of Photovoltaic Medium VoltageDirect Current(PV-MVDC)system,aHybrid Modulation Strategy based on theDecoupledDouble SynchronousReference Frame(DDSRF)control strategy is proposed.The dual armcomplementary hybrid modulation combining nearest-level-SPWM(NL-SPWM)can keep the number of SMs in the ON state constant.Then,the corresponding voltage sharing control algorithm of sub module(SM)is introduced.Through theoretical calculation,the modulation strategy can be found to stabilize the DC voltage and reduce the harmonic content.A32-level MMC systemhas been developed to verity that the proposed hybrid modulation strategy and its SM voltage sharing algorithm have the advantages of restraining circulating current and maintaining capacitor voltage balance. 展开更多
关键词 modular multilevel converter modulation strategy dual arm complementary nearest-level-modulation harmonics improvement
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基于改进SegFormer的超声影像分割方法研究
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作者 王高才 杨满 张晓洁 《现代电子技术》 北大核心 2025年第23期17-24,共8页
针对SegFormer网络分层的Transformer编码器逐级递减图像分辨率,提取图像多尺度特征的特点,文中提出一种边缘提取模块(EEM),该模块能更好地注意到超声影像的边界信息。为了解决超声图像中出现的复杂边界问题,在SegFormer编码层和解码层... 针对SegFormer网络分层的Transformer编码器逐级递减图像分辨率,提取图像多尺度特征的特点,文中提出一种边缘提取模块(EEM),该模块能更好地注意到超声影像的边界信息。为了解决超声图像中出现的复杂边界问题,在SegFormer编码层和解码层之间加入空洞空间卷积金字塔池化(ASPP)模块,确保其在获取较大感受野的同时不会发生网格效应。结合EEM和ASPP模块的SegFormer能够在保持低级边缘细节特征的同时进一步提取抽象特征,使得超声影像分割的精度进一步提升。将EEM连接在SegFormer编码器之前,再和解码器进行特征融合之后,与ASPP模块的输出特征做拼接并预测分割掩码,在甲状腺结节超声影像、乳腺结节超声影像和白细胞数据集上取得了较好的效果。经实验验证,该模型的mIoU分别提高了1.25%、2.2%和0.13%,证明了改进方法的有效性。 展开更多
关键词 图像分割 改进的SegFormer 超声影像 混合空洞卷积 混合通道注意力 边缘提取模块
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基于改进ConvNeXt网络和全景视觉技术的主动式矿井目标定位
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作者 刘毅 郭冠哲 +2 位作者 高宇翔 田子建 张力腾 《煤炭科学技术》 北大核心 2025年第11期185-200,共16页
针对井下无线定位系统部署成本高、抗灾变能力差的问题,提出了一种基于改进Conv NeXt网络和全景视觉技术的主动式井下目标定位方法。该方法分为离线训练和在线定位2个阶段:离线训练阶段,首先对井下环境进行区域划分并采集全景图像数据,... 针对井下无线定位系统部署成本高、抗灾变能力差的问题,提出了一种基于改进Conv NeXt网络和全景视觉技术的主动式井下目标定位方法。该方法分为离线训练和在线定位2个阶段:离线训练阶段,首先对井下环境进行区域划分并采集全景图像数据,通过数据增强构建多尺度训练集;然后基于改进的ConvNeXt网络分别训练区域定位模型和细致定位模型,其中区域定位模型实现粗粒度位置估计,细致定位模型完成精确定位;在线定位阶段,部署在移动设备上的全景相机实时采集环境图像,经图像拼接和增强预处理后,先通过区域定位模型确定目标所在区域范围,再调用对应区域的细致定位模型实现实时定位。试验结果表明:在0.5 m区域定位和0.1 m细致定位的组合下,定位准确率达到94%;通过引入CoordAttention模块,准确率进一步提升至95%,较传统单步方法提升14.67%。与MobileNetV3(91%)和ResNet(92.33%)相比,改进的ConvNeXt网络展现出更优的性能。此外,该方法对光照变化、运动模糊、人员走动、粉尘干扰等井下典型干扰表现出较强的鲁棒性,在国家能源集团宁夏煤业有限公司羊场湾煤矿井下616巷道数据集上的准确率达95.33%。研究为井下无人驾驶车辆和机器人等智能移动设备提供了一种低成本、高鲁棒性且易于实施的定位解决方案。 展开更多
关键词 井下目标定位 改进ConvNeXt网络 全景视觉技术 主动式定位 CoordAttention模块
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基于INC4-YOLO的菌落计数方法研究
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作者 陈教料 王振舵 潘立 《高技术通讯》 北大核心 2025年第8期901-910,共10页
针对菌落图像中小菌落易漏检的问题,提出了一种基于INC4-YOLO(you only look once)的计数方法,实现精准的菌落计数。采用带残差结构的Inception模块(Inception module with residual connection,IncRes)替换YOLOv5骨干网络中的Bottlenec... 针对菌落图像中小菌落易漏检的问题,提出了一种基于INC4-YOLO(you only look once)的计数方法,实现精准的菌落计数。采用带残差结构的Inception模块(Inception module with residual connection,IncRes)替换YOLOv5骨干网络中的Bottleneck模块,以增强图像特征提取能力。从网络的浅层特征中引出一个小目标检测头,以增强算法在训练过程中对小菌落的注意力。分别在标注微生物自动识别数据集(annotated germs for automated recognition,AGAR)和真实菌落计数场景下对INC4-YOLO进行计数性能测试。实验结果表明,在AGAR测试集中,提出的算法在小菌落的平均百分比绝对值计数误差(mean absolute percentage error,MAPE)比其他先进目标检测算法降低了2%;真实菌落计数场景下,INC4-YOLO的MAPE相比YOLOv5降低了7%,表明该算法可帮助菌落计数设备实现精准计数。 展开更多
关键词 菌落计数 目标检测 改进YOLOv5 Inception模块 小目标检测
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基于道路拓扑关联特征的城乡道路面精细提取网络
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作者 王艳军 唐徐超 +1 位作者 王成 蔡恒藩 《测绘学报》 北大核心 2025年第1期75-89,共15页
深度学习方法已成为基于遥感影像数据的城乡道路网分类提取的主流技术。然而,现有方法存在邻近地物(如植被和建筑物等)混杂遮挡、模型训练时间长、计算复杂度高等问题,并且大多仅关注道路面、边缘线和中心线等独立目标,导致道路分类提... 深度学习方法已成为基于遥感影像数据的城乡道路网分类提取的主流技术。然而,现有方法存在邻近地物(如植被和建筑物等)混杂遮挡、模型训练时间长、计算复杂度高等问题,并且大多仅关注道路面、边缘线和中心线等独立目标,导致道路分类提取结果精度不高。为了充分利用道路边缘与道路面之间的空间拓扑关系约束特征,本文提出了一种基于道路拓扑关联特征信息的道路面提取网络,记作CAS-DeepNet。首先,基于DeepLabV3+网络架构,改进轻量级MobileNetV2特征提取网络,嵌入基于残差连接的边缘增强模块以捕获道路边缘信息;其次,设计基于密集连接的CS-ASPP结构以提高模型性能;然后,引入通道注意力机制,有效地融合图像中的多分支通道,以提高特征表征能力;最后,通过道路边缘拓扑关联信息构建道路连通性约束,以提升道路网提取结果完整性。在CHN6-CUG和DeepGlobe等数据集进行试验,结果表明,本文设计的CAS-DeepNet与当前流行的U-Net++、DeepLabV3+、D-LinkNet、RoadNet、ACNet和SDUNet等方法相比,在准确率、召回率、F_(1)值和总体精度等评价指标方面更具优势,能够明显提升道路路网提取结果精度与完整性。本文方法可为自然资源调查监测和地理空间环境感知建模提供基础支撑。 展开更多
关键词 道路提取 边缘增强模块 改进DeepLabV3+ CS-ASPP 注意力机制
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转镜磁滞电动机低谐波设计及性能分析
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作者 杜怿 窦罗均 《江苏大学学报(自然科学版)》 北大核心 2025年第4期444-451,共8页
为提高磁滞电动机运行效率,提出不等匝同心式绕组(unequal turns concentric winding,UTCW)的低谐波设计方案.对磁滞电动机的基本结构和运行原理进行了讨论,基于磁场调制原理对气隙磁场进行了分析,从而揭示出气隙磁场高次谐波是降低磁... 为提高磁滞电动机运行效率,提出不等匝同心式绕组(unequal turns concentric winding,UTCW)的低谐波设计方案.对磁滞电动机的基本结构和运行原理进行了讨论,基于磁场调制原理对气隙磁场进行了分析,从而揭示出气隙磁场高次谐波是降低磁滞电动机运行效率和转矩密度的根本原因;对UTCW设计进行了理论推导,并获得了一台18/2极磁滞电动机的低谐波绕组设计方案;建立了磁滞电动机有限元模型,对磁滞电动机的性能进行了计算;试制了磁滞电动机样机,并进行了测试.结果表明,相比于传统分布式绕组电动机,UTCW电动机的转矩可提升11.4%,转矩脉动降低5.5百分点,运行效率提升9百分点,可见所提出的UTCW可有效改善磁滞电动机性能. 展开更多
关键词 磁滞电动机 不等匝同心式绕组(UTCW) 低谐波 磁场调制 有限元模型 转矩提升
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改进YOLOv8的城市行车道路障碍物检测算法研究 被引量:6
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作者 向雷 蒋文波 《电子测量技术》 北大核心 2025年第1期29-38,共10页
针对目前城市道路复杂环境下障碍物检测精度不足、检测速度慢、模型参数量大和小目标障碍物检测效果不佳的问题,提出一种改进的YOLOv8n轻量级城市行车道路障碍物检测算法。首先,制作MRObstacle城市道路障碍物目标检测数据集,扩展了障碍... 针对目前城市道路复杂环境下障碍物检测精度不足、检测速度慢、模型参数量大和小目标障碍物检测效果不佳的问题,提出一种改进的YOLOv8n轻量级城市行车道路障碍物检测算法。首先,制作MRObstacle城市道路障碍物目标检测数据集,扩展了障碍物检测种类与数量;其次,设计全新的SPS_C2f改进主干网络,降低网络参数量与提升检测速度,添加M_ECA注意力模块至网络的Neck部分,提升网络检测速度与特征表达能力;再次,融合BiFPN特征金字塔和添加小目标检测头,更好地捕捉小尺寸障碍物的特征;最后,使用可优化边界框宽度与高度值的损失函数MPDIoU,提升网络边界框回归性能。相比于原YOLOv8n算法,该算法的mAP0.5指标提升2.04%,达到97.12%;FPS值提升12.08 fps,达到107.45 fps;网络参数量减少10%,降低至2.73 MB。该算法在减少参数量的同时提高了检测精度和速度,可更好应用于城市行车道路障碍物检测任务。 展开更多
关键词 障碍物检测 YOLOv8 改进C2f模块 改进注意力机制 损失函数
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基于非气隙侧调制的永磁电机绕组因数提升机理 被引量:1
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作者 贾晨 吉敬华 +3 位作者 凌志健 赵文祥 曾煜 罗泽宇 《中国电机工程学报》 北大核心 2025年第4期1260-1270,I0004,共12页
磁场调制电机因具有高转矩密度而受到广泛关注。首先,以12槽19对极传统磁场调制电机为研究对象,讨论定子开空气槽对绕组因数的影响。结果表明,将空气槽开在绕线齿处可以使绕组原始磁动势变化,进而导致绕组因数变化。通过推导模块化张角... 磁场调制电机因具有高转矩密度而受到广泛关注。首先,以12槽19对极传统磁场调制电机为研究对象,讨论定子开空气槽对绕组因数的影响。结果表明,将空气槽开在绕线齿处可以使绕组原始磁动势变化,进而导致绕组因数变化。通过推导模块化张角变化对工作谐波绕组因数的影响,演化出一种绕组因数提升型磁场调制电机。其次,基于能量法分析对比绕组因数提升型结构和传统结构的谐波对转矩的贡献,并利用有限元进行验证。研究表明,绕组因数提升型结构可进一步提升工作谐波的绕组因数,进而实现转矩的提升。最后,制造了样机,通过实验验证了解析计算和有限元仿真的合理性。 展开更多
关键词 非气隙侧磁场调制 绕组因数提升 磁场调制电机 能量法
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基于多状态耦合的退役动力电池模组双阶段分选方法 被引量:1
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作者 李春生 王生春 +2 位作者 宋驰 刘立海 颜宁 《储能科学与技术》 北大核心 2025年第2期822-830,共9页
为有效降低退役动力电池梯次利用寿命损耗,提高电池模组运行过程中功能状态的一致性,本工作提出了考虑电池能量状态(state of energy,SOE)、健康状态(state of health,SOH)及功率状态(state of power,SOP)的多状态耦合的电池模组分选方... 为有效降低退役动力电池梯次利用寿命损耗,提高电池模组运行过程中功能状态的一致性,本工作提出了考虑电池能量状态(state of energy,SOE)、健康状态(state of health,SOH)及功率状态(state of power,SOP)的多状态耦合的电池模组分选方法。首先,提取退役动力电池基本电性能参数(如容量、电压、内阻等),建立了电池模组SOE、SOH及SOP多状态耦合表征模型;其次,估计电池模组SOE特性,预测梯次利用电池模组SOH一致性,采用改进K-means聚类算法对电池模组进行了第一阶段的动态分选。最后,建立了电池模组耦合多参量的SOP表征模型,估计了电池模组中电池之间SOP偏差,对电池模组进行了第二阶段的动态分选。通过仿真算例分析验证该方法有效提高了退役动力电池梯次利用过程中模组的一致性,降低了系统运行的寿命损耗,为梯次利用储能大规模应用提供理论基础。 展开更多
关键词 多状态耦合 退役动力电池模组 双阶段分选 改进K-means聚类 动态一致性
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考虑零件重用的复杂产品模块划分方法
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作者 郝娟 高新勤 +2 位作者 刘永 韩周鹏 宋恩恩 《现代制造工程》 北大核心 2025年第5期20-26,52,共8页
针对复杂产品设计周期长、成本高的问题,提出了一种考虑零件重用的模块划分方法。首先,对复杂产品零件的功能、物理和重用性3种关联度属性进行分析,构建零件间综合关联关系矩阵,并结合复杂网络理论,映射为关联关系网络模型。然后,提出... 针对复杂产品设计周期长、成本高的问题,提出了一种考虑零件重用的模块划分方法。首先,对复杂产品零件的功能、物理和重用性3种关联度属性进行分析,构建零件间综合关联关系矩阵,并结合复杂网络理论,映射为关联关系网络模型。然后,提出改进的Louvain社区发现算法,通过选取种子节点的方式解决小社区过多的问题,实现复杂产品模块划分。最后,以排屑机为例进行模块划分,并与Louvain社区发现算法和谱聚类算法获得的划分方案进行比较,验证所提方法的有效性和可行性。 展开更多
关键词 复杂产品 零件重用 改进的Louvain社区发现算法 模块划分
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级联型风电系统四有源桥变换器绕组电流偏置特性分析及改进调制策略
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作者 彭新 张永磊 +2 位作者 原熙博 覃育焕 李炎 《电工技术学报》 北大核心 2025年第20期6658-6671,共14页
基于四有源桥变换器隔离的级联型风力发电变流器具有模块化结构且高电压的特点,通过瞬时功率的聚合传输可以直接消除低频电压脉动,大幅减小直流侧电容,在20 MW及以上功率等级的海上风力发电系统中具有重要的应用前景。然而四有源桥变换... 基于四有源桥变换器隔离的级联型风力发电变流器具有模块化结构且高电压的特点,通过瞬时功率的聚合传输可以直接消除低频电压脉动,大幅减小直流侧电容,在20 MW及以上功率等级的海上风力发电系统中具有重要的应用前景。然而四有源桥变换器传输脉动功率时,其输入绕组电流出现偏置问题,增大了电流应力和系统损耗。该文以四有源桥变换器解耦等效模型和单移相调制策略为基础,分析瞬时功率聚合传输过程中绕组电流偏置的原因,揭示电流幅值的波动特性。并提出一种改进调制方法,在保留原有移相角的基础上,增加内移相角来平衡输入绕组电压正、负极性占空比,实现变换器一次侧漏感伏秒平衡,绕组电流的正、负幅值对称波动,进而消除绕组电流的偏置,降低变换器的电流应力和损耗。通过仿真和实验结果,验证了所提改进移相调制策略的正确性。 展开更多
关键词 级联型风力发电变流器 四有源桥变换器 绕组电流偏置 改进移相调制
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一种基于改进YOLOv8n的蜗杆表面缺陷检测方法
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作者 张豪杰 郑鹏 +2 位作者 乔王威 王明基 李季村 《机床与液压》 北大核心 2025年第16期10-17,共8页
小模数蜗杆是工业中常用的机械零件,但其表面结构复杂且几何尺寸较小,导致表面缺陷检测难度大,检测精度和效率均较低。为解决这一问题,提出一种基于改进YOLOv8n模型的蜗杆表面缺陷检测方法。针对蜗杆的缺陷特点和材料特性,设计图像采集... 小模数蜗杆是工业中常用的机械零件,但其表面结构复杂且几何尺寸较小,导致表面缺陷检测难度大,检测精度和效率均较低。为解决这一问题,提出一种基于改进YOLOv8n模型的蜗杆表面缺陷检测方法。针对蜗杆的缺陷特点和材料特性,设计图像采集装置。通过引入C2fCIB模块,有效降低YOLOv8n模型的参数量和计算复杂度;结合高效通道注意力(ECA)机制,在不增加模型规模的前提下提升特征提取能力。此外,引入Focaler-CIoU损失函数,有效缓解困难样本与简单样本分布不平衡的问题,进一步提高检测精度。最终,通过继续训练方法优化模型。实验结果表明:该方法在检测精度、mAP@50、FPS等方面均优于现有主流算法,检测精度达到91.4%,mAP@50达到91.8%,FPS达到191.6,参数量和浮点运算次数分别为2.79×10^(6)和7.9×10^(9),基本能够满足工业实际应用需求。 展开更多
关键词 小模数蜗杆 缺陷检测 改进YOLOv8n模型 注意力机制 损失函数
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基于CELMDAN与IMOMEDA的微弱机械特征增强方法 被引量:1
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作者 顾张清 黄清岩 +1 位作者 任世锦 郝国生 《常州大学学报(自然科学版)》 2025年第3期75-86,92,共13页
针对设备背景噪声影响机械故障检测的问题,提出一种融合自适应噪声完全集成局部均值分解(Complete Ensemble Local Mean Decomposition with Adaptive Noise,CELMDAN)与改进的多点最优最小熵去卷积调整(Improved Multipoint Optimal Min... 针对设备背景噪声影响机械故障检测的问题,提出一种融合自适应噪声完全集成局部均值分解(Complete Ensemble Local Mean Decomposition with Adaptive Noise,CELMDAN)与改进的多点最优最小熵去卷积调整(Improved Multipoint Optimal Minimum Entropy Deconvolution Adjusted,IMOMEDA)的微弱机械特征增强方法。该方法首先利用CELMDAN方法把复杂振动信号分解为多个单模态的乘积函数(Product Functions,PFs),解决了集成局部均值分解(Ensemble Local Mean Decomposition,ELMD)对信号施加噪声幅值和试错次数难以确定的问题。其次,提出一种具有鲁棒性较强、物理意义明确以及尺度不变性的周期调制强度(Periodic Modulation Intensity,PMI),以筛选出有效的PFs。接着,针对所选PFs中的噪声,提出IMOMEDA方法进行消除,该方法通过迭代估计最优模型参数,自适应地提取振动信号中的周期性故障瞬态特征,能够在频域中定位瞬态的谱峭度,从而抽取被背景噪声淹没的微弱故障特征。最后,以煤矿提升机为研究对象,设计了多种振动信号特征增强方法对比实验、机械运行状态诊断性能实验以及信号特征增强算法性能对比实验,多角度验证了本文方法的有效性。 展开更多
关键词 微弱故障信号增强 改进的多点最优最小熵去卷积调整 自适应噪声完全集成局部均值分解 周期调制强度 煤矿提升机
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