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Weak Co-AB-context for G_(C)-χ-injective Modules
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作者 YANG Qiang 《数学进展》 北大核心 2026年第1期103-119,共17页
In this paper,we introduce the notion of G_(C)-X-injective modules,where X denotes a class of left S-modules and C represents a faithfully semidualizing bimodule.Under the condition that X satisfies certain hypotheses... In this paper,we introduce the notion of G_(C)-X-injective modules,where X denotes a class of left S-modules and C represents a faithfully semidualizing bimodule.Under the condition that X satisfies certain hypotheses,some properties and some equivalent characterizations of G_(C)-X-injective modules are investigated,and we also show that the triple(■,cores■,■)is a weak co-AB-context.As an application,two complete cotorsion pairs and a new model structure in Mod S are given. 展开更多
关键词 C-X-injective module G_(C)-X-injective module cotorsion pair weak co-ABcontext
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Enhancing Lightweight Mango Disease Detection Model Performance through a Combined Attention Module
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作者 Wen-Tsai Sung Indra Griha TofikIsa Sung-Jung Hsiao 《Computers, Materials & Continua》 2026年第2期986-1016,共31页
Mango is a plant with high economic value in the agricultural industry;thus,it is necessary to maximize the productivity performance of the mango plant,which can be done by implementing artificial intelligence.In this... Mango is a plant with high economic value in the agricultural industry;thus,it is necessary to maximize the productivity performance of the mango plant,which can be done by implementing artificial intelligence.In this study,a lightweight object detection model will be developed that can detect mango plant conditions based on disease potential,so that it becomes an early detection warning system that has an impact on increasing agricultural productivity.The proposed lightweight model integrates YOLOv7-Tiny and the proposed modules,namely the C2S module.The C2S module consists of three sub-modules such as the convolutional block attention module(CBAM),the coordinate attention(CA)module,and the squeeze-and-excitation(SE)module.The dataset is constructed by eight classes,including seven classes of disease conditions and one class of health conditions.The experimental result shows that the proposed lightweight model has the optimal results,which increase by 13.15% of mAP50 compared to the original model YOLOv7-Tiny.While the mAP50:95 also achieved the highest results compared to other models,including YOLOv3-Tiny,YOLOv4-Tiny,YOLOv5,and YOLOv7-Tiny.The advantage of the proposed lightweightmodel is the adaptability that supports it in constrained environments,such as edge computing systems.This proposedmodel can support a robust,precise,and convenient precision agriculture system for the user. 展开更多
关键词 Mango lightweight model combined attention module C2S module precision agriculture
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An attention module integrated hybrid model for recognizing microseismic signals induced by high-pressure grouting in deep rock layers
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作者 Yongshu Zhang Lianchong Li +2 位作者 Wenqiang Mu Jian Chen Peng Chen 《International Journal of Mining Science and Technology》 2026年第3期595-613,共19页
Microseismic(MS)monitoring is an effective technique to detect mining-induced rock fractures.However,recognizing grouting-induced signals is challenging due to complex geological conditions in deep rock plates.Therefo... Microseismic(MS)monitoring is an effective technique to detect mining-induced rock fractures.However,recognizing grouting-induced signals is challenging due to complex geological conditions in deep rock plates.Therefore,a hybrid model(WM-ResNet50)integrating data enhancement,a deep convolutional neural network(CNN),and convolutional block attention modules(CBAM)was proposed.Firstly,an MS system was established at the Xieqiao coal mine in Anhui Province,China.MS waveforms and injection parameters were acquired during grouting.Secondly,signals were categorized based on time-frequency characteristics to build a dataset,which was divided into training,validation,and test sets at a ratio of 4:1:1.Subsequently,the performance of WM-ResNet50 was evaluated based on indices such as individual precision,total accuracy,recall,and loss function.The results indicated that WMResNet50 achieved an average recognition accuracy of 94.38%,surpassing that of a simple CNN(90.04%),ResNet18(91.72%),and ResNet50(92.48%).Finally,WM-ResNet50 was applied to monitor the whole process at laboratory tests and field cases.Both results affirmed the feasibility and effectiveness of MS inversion in predicting actual slurry diffusion ranges within deep rock layers.By comparison,it was revealed that the MS sources classified by WM-ResNet50 matched grouting records well.A solution to address insufficient diffusion under long-borehole grouting has been proposed.WM-ResNet50′s accuracy was validated through in-situ coring and XRD analysis for cement-based hydration products.This study provides a beneficial reference for similar rock signal processing and in-field grouting practices. 展开更多
关键词 Attention module Convolutional neural network Microseismic ROCK Grouting-induced signals Slurry diffusion
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微课驱动小学生英语自主学习能力提升的探究——以Module 5 Unit 9 Where will you go?第一课时自主学习为例
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作者 张兴 《视周刊》 2026年第1期34-35,共2页
一、微课设计:从知识传递到认知建构的范式转变1.微课定义微课是一种以短小精悍的数字视频为主要载体,围绕某个知识点、教学环节或特定教学主题而设计的结构化、情境化教学资源。其时长通常在5-10分钟之间,内容高度聚焦,重点突出,针对性... 一、微课设计:从知识传递到认知建构的范式转变1.微课定义微课是一种以短小精悍的数字视频为主要载体,围绕某个知识点、教学环节或特定教学主题而设计的结构化、情境化教学资源。其时长通常在5-10分钟之间,内容高度聚焦,重点突出,针对性强,符合学生的认知负荷与注意力特点,旨在通过精炼的内容和生动的呈现方式,激发学生学习兴趣,支持个性化、碎片化学习,促进自主探究与合作交流,是现代教育信息化背景下一种重要的教学辅助手段与课程资源形态。 展开更多
关键词 英语 module 5 Unit 9 能力提升 自主学习 微课
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An RMD-YOLOv11 Approach for Typical Defect Detection of PV Modules
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作者 Tao Geng Shuaibing Li +3 位作者 Yunyun Yun Yongqiang Kang Hongwei Li unmin Zhu 《Computers, Materials & Continua》 2026年第3期1804-1822,共19页
In order to address the challenges posed by complex background interference,high miss-detection rates of micro-scale defects,and limited model deployment efficiency in photovoltaic(PV)module defect detection,this pape... In order to address the challenges posed by complex background interference,high miss-detection rates of micro-scale defects,and limited model deployment efficiency in photovoltaic(PV)module defect detection,this paper proposes an efficient detection framework based on an improved YOLOv11 architecture.First,a Re-parameterized Convolution(RepConv)module is integrated into the backbone to enhance the model’s sensitivity to fine-grained defects—such as micro-cracks and hot spots—while maintaining high inference efficiency.Second,a Multi-Scale Feature Fusion Convolutional Block Attention Mechanism(MSFF-CBAM)is designed to guide the network toward critical defect regions by jointly modeling channel-wise and spatial attention.This mechanism effectively strengthens the specificity and robustness of feature representations.Third,a lightweight Dynamic Sampling Module(DySample)is employed to replace conventional upsampling operations,thereby improving the localization accuracy of small-scale defect targets.Experimental evaluations conducted on the PVEL-AD dataset demonstrate that the proposed RMDYOLOv11 model surpasses the baseline YOLOv11 in terms of mean Average Precision(mAP)@0.5,Precision,and Recall,achieving respective improvements of 4.70%,1.51%,and 5.50%.The model also exhibits notable advantages in inference speed and model compactness.Further validation on the ELPV dataset confirms the model’s generalization capability,showing respective performance gains of 1.99%,2.28%,and 1.45%across the same metrics.Overall,the enhanced model significantly improves the accuracy of micro-defect identification on PV module surfaces,effectively reducing both false negatives and false positives.This advancement provides a robust and reliable technical foundation for automated PV module defect detection. 展开更多
关键词 Photovoltaic(PV)modules YOLOv11 re-parameterization convolution attention mechanism dynamic upsampling
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Human Activity Recognition Using a CNN with an Enhanced Convolutional Block Attention Module
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作者 HU Biling TONG Yu 《Wuhan University Journal of Natural Sciences》 2026年第1期10-24,共15页
WiFi-based human activity recognition(HAR)provides a non-intrusive approach for ubiquitous monitoring;however,achieving both high accuracy and robustness simultaneously remains a significant challenge.This paper propo... WiFi-based human activity recognition(HAR)provides a non-intrusive approach for ubiquitous monitoring;however,achieving both high accuracy and robustness simultaneously remains a significant challenge.This paper proposes a Convolutional Neural Network with Enhanced Convolutional Block Attention Module(CNN-ECBAM)framework.The approach systematically converts raw Channel State Information(CSI)into pseudo-color images,effectively preserving essential signal characteristics for deep neural network processing.The core innovation is an Enhanced Convolutional Block Attention Module(ECBAM),tailored to CSI data characteristics,which integrates Efficient Channel Attention(ECA)and Multi-Scale Spatial Attention(MSSA).By employing learnable adaptive fusion weights,it achieves dynamic synergy between channel and spatial features,enabling the network to capture highly discriminative spatiotemporal patterns.The ECBAM module is integrated into a unified Convolutional Neural Network(CNN)to form the overall CNN-ECBAM model.Experimental results on the UT-HAR and NTU-Fi_HAR datasets demonstrate that CNN-ECBAM achieves competitive performance in recognition accuracy and outperforms mainstream baseline models.Specifically,it attains 99.20%accuracy on UT-HAR(surpassing ResNet-18 at 98.60%)and achieves 100%accuracy on NTU-Fi_HAR(exceeding GAF-CNN at 99.62%).These results validate the effectiveness of the proposed method for high-precision and reliable WiFi-based HAR. 展开更多
关键词 human activity recognition deep learning channel state information Enhanced Convolutional Block Attention module(ECBAM) pseudo-color images
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一种高增益软开关准Z源DC-DC变换器
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作者 张涛 白文龙 +3 位作者 张丽 韩庆林 李云飞 张亚飞 《太阳能学报》 北大核心 2026年第2期8-17,共10页
针对传统准Z源DC-DC变换器存在电压增益低和器件电压应力高的问题,提出一种高增益软开关准Z源DC-DC变换器(HGSS-QZS)。通过三绕组耦合电感匝比和开关管占空比共同调节,可提高升压能力和增益调节的自由度;并利用钳位电路吸收耦合电感的... 针对传统准Z源DC-DC变换器存在电压增益低和器件电压应力高的问题,提出一种高增益软开关准Z源DC-DC变换器(HGSS-QZS)。通过三绕组耦合电感匝比和开关管占空比共同调节,可提高升压能力和增益调节的自由度;并利用钳位电路吸收耦合电感的漏感能量,降低漏感引起的电压尖峰。首先详细分析HGSS-QZS变换器的工作原理,推导出电压增益、器件电压电流应力和效率损耗,其次进行参数设计并与现有变换器对比。表明HGSS-QZS变换器具有电压增益高、器件电压应力低、软开关和效率高的优点。最后搭建200 W实验样机,结合仿真与实验对比验证了HGSS-QZS变换器的有效性和可行性。 展开更多
关键词 dc-dc变换器 准Z源 高增益 光伏发电 软开关 耦合电路 三绕组
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基于TD3强化学习的光储微网双向DC-DC变换器自抗扰控制研究
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作者 马幼捷 胡钰 +3 位作者 周雪松 闫凤祥 白鑫 陶珑 《太阳能学报》 北大核心 2026年第1期202-213,共12页
考虑到高比例新能源接入带来的不确定性问题会导致微电网直流母线电压的大幅波动难以平抑,该文提出一种基于双延迟深度确定性策略梯度算法(TD3)强化学习的双向DC-DC变换器的自抗扰控制策略。首先,利用线性扩张状态观测器进行系统重构来... 考虑到高比例新能源接入带来的不确定性问题会导致微电网直流母线电压的大幅波动难以平抑,该文提出一种基于双延迟深度确定性策略梯度算法(TD3)强化学习的双向DC-DC变换器的自抗扰控制策略。首先,利用线性扩张状态观测器进行系统重构来实现对总扰动的估计补偿,并就控制策略的跟踪性和抗扰性进行频域分析。接着,通过大量的仿真交互自学习获得观测器参数来智能调节神经网络的权值更新方式,优化奖励函数形式,并在线利用网络进行参数实时调度,使其充分训练以实现近似最优控制律。最后,利用数字仿真平台和小功率实验验证了在多工况下所提控制策略较双闭环PI控制和传统线性自抗扰控制具有更小的电压偏差及更快的响应速度等优越的动稳态性能,有效提升了直流母线电压的抗扰能力。 展开更多
关键词 双向dc-dc变换器 光储微电网 自抗扰控制 TD3深度强化学习算法
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隔离型三有源桥DC-DC变换器端口解耦及回流功率优化控制
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作者 陶海军 宋佳瑶 +1 位作者 赵蒙恩 张晨杰 《电机与控制学报》 北大核心 2026年第1期107-116,共10页
三有源桥DC-DC变换器广泛应用于光伏发电、电动汽车等高功率输电场合。然而,功率在传输过程中会在端口间产生耦合现象,这不仅降低了系统动态性能,还会导致功率流失。为此,设计一种三有源桥DC-DC变换器性能优化策略。该策略对移相方式进... 三有源桥DC-DC变换器广泛应用于光伏发电、电动汽车等高功率输电场合。然而,功率在传输过程中会在端口间产生耦合现象,这不仅降低了系统动态性能,还会导致功率流失。为此,设计一种三有源桥DC-DC变换器性能优化策略。该策略对移相方式进行优化,在传统双重移相的基础上进行改进,通过控制各端口全桥电压移相比的重合,提出一种新型双重移相控制方法。在此基础之上,引入模拟退火粒子群混合优化算法,以回流功率最小化为目标函数,经过对各个移相角的迭代筛选,最终计算出使回流功率达到全局最优的移相角组合。仿真和实验结果表明,该控制策略有效消除了端口间的耦合功率,显著降低了回流功率,提升了变换器的整体效率和动态响应速度,从而增强了系统的可靠性与工程适用性。 展开更多
关键词 三有源桥dc-dc变换器 新双重移相控制 解耦 回流功率 模拟退火粒子群算法
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Remaining Life Prediction Method for Photovoltaic Modules Based on Two-Stage Wiener Process 被引量:1
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作者 Jie Lin Hongchi Shen +1 位作者 Tingting Pei Yan Wu 《Energy Engineering》 EI 2025年第1期331-347,共17页
Photovoltaic (PV) modules, as essential components of solar power generation systems, significantly influence unitpower generation costs.The service life of these modules directly affects these costs. Over time, the p... Photovoltaic (PV) modules, as essential components of solar power generation systems, significantly influence unitpower generation costs.The service life of these modules directly affects these costs. Over time, the performanceof PV modules gradually declines due to internal degradation and external environmental factors.This cumulativedegradation impacts the overall reliability of photovoltaic power generation. This study addresses the complexdegradation process of PV modules by developing a two-stage Wiener process model. This approach accountsfor the distinct phases of degradation resulting from module aging and environmental influences. A powerdegradation model based on the two-stage Wiener process is constructed to describe individual differences inmodule degradation processes. To estimate the model parameters, a combination of the Expectation-Maximization(EM) algorithm and the Bayesian method is employed. Furthermore, the Schwarz Information Criterion (SIC) isutilized to identify critical change points in PV module degradation trajectories. To validate the universality andeffectiveness of the proposed method, a comparative analysis is conducted against other established life predictiontechniques for PV modules. 展开更多
关键词 Photovoltaic modules DEGRADATION stochastic processes lifetime prediction
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A review of encapsulation methods and geometric improvements of perovskite solar cells and modules for mass production and commercialization 被引量:1
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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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基于扩展移相的双有源桥DC-DC变换器电流应力优化与模型预测混合控制
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作者 邹梓洋 张长征 +1 位作者 张杰 袁雷 《太阳能学报》 北大核心 2026年第1期386-394,共9页
为提升双有源桥DC-DC变换器在直流微电网发生扰动下的性能,该文针对双有源桥DC-DC变换器动态响应性能与应力优化问题展开研究,并提出一种新型混合控制策略。该策略融合了扩展移相调制和模型预测控制,旨在降低变换器电流应力,并通过优化... 为提升双有源桥DC-DC变换器在直流微电网发生扰动下的性能,该文针对双有源桥DC-DC变换器动态响应性能与应力优化问题展开研究,并提出一种新型混合控制策略。该策略融合了扩展移相调制和模型预测控制,旨在降低变换器电流应力,并通过优化控制提升动态响应与稳态精度。此外,鉴于模型预测控制对参数的敏感性,引入误差校正方法作为反馈校正环节,以消除因参数失配所引起的稳态误差,从而提高系统的控制精度与系统鲁棒性。仿真与实验均验证了所提控制策略的实用性与优越性。 展开更多
关键词 dc-dc变换器 模型预测控制 微电网 电流应力优化 扩展移相
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A Two-Stage Wiener Degradation Model-Based Approach for Visual Maintenance of Photovoltaic Modules 被引量:1
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作者 Jie Lin Hongchi Shen +1 位作者 Tingting Pei Yan Wu 《Energy Engineering》 2025年第6期2449-2463,共15页
This study proposes a novel visual maintenance method for photovoltaic(PV)modules based on a two-stage Wiener degradation model,addressing the limitations of traditional PV maintenance strategies that often result in ... This study proposes a novel visual maintenance method for photovoltaic(PV)modules based on a two-stage Wiener degradation model,addressing the limitations of traditional PV maintenance strategies that often result in insufficient or excessive maintenance.The approach begins by constructing a two-stage Wiener process performance degradation model and a remaining life prediction model under perfect maintenance conditions using historical degradation data of PV modules.This enables accurate determination of the optimal timing for postfailure corrective maintenance.To optimize the maintenance strategy,the study establishes a comprehensive cost model aimed at minimizing the long-term average cost rate.The model considers multiple cost factors,including inspection costs,preventive maintenance costs,restorative maintenance costs,and penalty costs associated with delayed fault detection.Through this optimization framework,the method determines both the optimal maintenance threshold and the ideal timing for predictive maintenance actions.Comparative analysis demonstrates that the twostage Wiener model provides superior fitting performance compared to conventional linear and nonlinear degradation models.When evaluated against traditional maintenance approaches,including Wiener process-based corrective maintenance strategies and static periodic maintenance strategies,the proposed method demonstrates significant advantages in reducing overall operational costs while extending the effective service life of PV components.The method achieves these improvements through effective coordination between reliability optimization and economic benefit maximization,leading to enhanced power generation performance.These results indicate that the proposed approach offers a more balanced and efficient solution for PV system maintenance. 展开更多
关键词 Photovoltaic module remaining life maintenance strategy Wiener modeling
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EL-DenseNet:Mushroom Recognition Based on Erasing Module Using DenseNet
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作者 WANG Yaojun ZHAO Weiting +1 位作者 BIE Yuhui JIA Lu 《农业机械学报》 北大核心 2025年第9期628-637,共10页
Target occlusion poses a significant challenge in computer vision,particularly in agricultural applications,where occlusion of crops can obscure key features and impair the model’s recognition performance.To address ... Target occlusion poses a significant challenge in computer vision,particularly in agricultural applications,where occlusion of crops can obscure key features and impair the model’s recognition performance.To address this challenge,a mushroom recognition method was proposed based on an erase module integrated into the EL-DenseNet model.EL-DenseNet,an extension of DenseNet,incorporated an erase attention module designed to enhance sensitivity to visible features.The erase module helped eliminate complex backgrounds and irrelevant information,allowing the mushroom body to be preserved and increasing recognition accuracy in cluttered environments.Considering the difficulty in distinguishing similar mushroom species,label smoothing regularization was employed to mitigate mislabeling errors that commonly arose from human observers.This strategy converted hard labels into soft labels during training,reducing the model’s overreliance on noisy labels and improving its generalization ability.Experimental results showed that the proposed EL-DenseNet,when combined with transfer learning,achieved a recognition accuracy of 96.7%for mushrooms in occluded and complex backgrounds.Compared with the original DenseNet and other classic models,this approach demonstrated superior accuracy and robustness,providing a promising solution for intelligent mushroom recognition. 展开更多
关键词 mushroom recognition erase module label smoothing DenseNet
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基于自适应二次斜坡补偿的高效峰值电流模式Buck DC-DC
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作者 李旭阳 周晓笛 +2 位作者 吴燕文 郝松茂 石春琦 《华东师范大学学报(自然科学版)》 北大核心 2026年第2期95-107,共13页
本文提出了一种自适应二次斜坡补偿的高效率峰值电流模式(Peak Current Mode, PCM)的Buck DC-DC芯片,通过自适应二次斜坡补偿技术,使该芯片在宽输入电压、宽输出电压、宽负载电流、宽开关频率范围内均能实现不同的自适应斜坡电压,具有... 本文提出了一种自适应二次斜坡补偿的高效率峰值电流模式(Peak Current Mode, PCM)的Buck DC-DC芯片,通过自适应二次斜坡补偿技术,使该芯片在宽输入电压、宽输出电压、宽负载电流、宽开关频率范围内均能实现不同的自适应斜坡电压,具有优秀的瞬态响应.该芯片采用55 nm BCD工艺设计,核心面积仅为0.186 mm^(2).可以在输入电压为3.7~5.0 V,输出电压为1.5~3.5 V,最大负载电流为1.00 A以及开关频率为1.0~4.0 MHz的条件下工作,峰值效率高达96.0%,输出电流为1.00 A时效率超过93.0%,在0.03~1.00 A负载电流范围内效率均大于90.0%.后仿真结果表明,所提出的补偿方法对不同应用配置均具有良好的适应性. 展开更多
关键词 自适应斜坡补偿 高效率 峰值电流模式 Buck dc-dc转换器
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燃料电池集成在线EIS检测的DC-DC转换技术研究进展
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作者 高天乐 杨亚红 何小斌 《粘接》 2026年第4期1174-1178,共5页
在燃料电池系统中,集成在线电化学阻抗谱(EIS)检测的DC-DC变换器技术是一条极具吸引力的技术路线。该技术将功率变换器用于燃料电池运行状态的检测,利用其开关特性注入交流激励信号,并同步采集响应以实时获取燃料电池阻抗谱,克服了传统... 在燃料电池系统中,集成在线电化学阻抗谱(EIS)检测的DC-DC变换器技术是一条极具吸引力的技术路线。该技术将功率变换器用于燃料电池运行状态的检测,利用其开关特性注入交流激励信号,并同步采集响应以实时获取燃料电池阻抗谱,克服了传统离线EIS设备昂贵、无法实时监测的问题。本综述对燃料电池集成在线EIS检测的DC-DC变换器技术的研究现状进行了系统性的梳理和综述,首先介绍了电化学阻抗谱检测的基本原理,然后重点剖析与对比了基于不同扰动方式的实现方案,并深入探讨相关技术细节,最后总结当前所面临的挑战,并指出其未来潜在的研究的方向。 展开更多
关键词 燃料电池 dc-dc变换器 在线EIS检测 集成化
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一种零输入电流纹波高升压软开关DC-DC变换器
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作者 周明珠 刘超 +2 位作者 庄一展 毛行奎 张艺明 《仪器仪表学报》 北大核心 2026年第1期25-36,共12页
高升压DC-DC变换器广泛应用于光伏(PV)发电、燃料电池、直流微电网和混合动力电动汽车等领域。本研究提出了一种零输入电流纹波(ZICR)高升压软开关DC-DC变换器。其通过将输入电感电压箝位在零电压的方式实现ZICR,有效消除输入电流纹波;... 高升压DC-DC变换器广泛应用于光伏(PV)发电、燃料电池、直流微电网和混合动力电动汽车等领域。本研究提出了一种零输入电流纹波(ZICR)高升压软开关DC-DC变换器。其通过将输入电感电压箝位在零电压的方式实现ZICR,有效消除输入电流纹波;较低的输入电流纹波可提高光伏电池板和燃料电池的发电效率和使用寿命。该变换器通过引入耦合电感和开关电容升压技术来实现高电压增益,利用开关管导通占空比和耦合电感匝比灵活调节输出电压。同时,该变换器中所有开关都实现了零电压开关(ZVS),所有二极管都实现了零电流开关(ZCS),这样可以降低开关的开关损耗和二极管的反向恢复损耗,进而降低开关器件的损耗来提高变换器的工作效率。详细分析了变换器的工作原理、ZICR特性、电压电流应力和软开关特性,并将所提ZICR变换器与其它相似的高升压DC-DC变换器进行了性能参数比较。最后,搭建了一台100 kHz、200 W、38~380 V的实验样机,验证了所提ZICR变换器在额定功率下的拓扑结构性能和理论分析的正确性。同时,在额定功率下具有ZICR和不具有ZICR的变换器的实验效率分别为95.4%和96.1%。实验结果表明该ZICR变换器具有良好的稳态性能,能够实现高电压增益和高效率输出,满足新能源与直流微电网之间的功率变换应用需求,是一种性能优越的高升压DC-DC变换器拓扑。 展开更多
关键词 高升压dc-dc变换器 零输入电流纹波 耦合电感 零电压开关 零电流开关
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基于SEPIC的新型高增益DC-DC变换器
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作者 全以恒 魏业文 +1 位作者 贺晓倩 周志鹏 《自动化与仪表》 2026年第3期96-101,共6页
针对新能源系统中变换器存在电压增益受限与功率器件电压应力过高问题,该文提出了一种基于SEPIC拓扑的级联型高增益DC-DC变换器。在传统SEPIC变换器中引入了开关电容网络,通过叠加多个电容电压,不仅实现了高增益,还有效减少了输入电流纹... 针对新能源系统中变换器存在电压增益受限与功率器件电压应力过高问题,该文提出了一种基于SEPIC拓扑的级联型高增益DC-DC变换器。在传统SEPIC变换器中引入了开关电容网络,通过叠加多个电容电压,不仅实现了高增益,还有效减少了输入电流纹波,并显著降低半导体器件的电压应力。该文对CCM与DCM两种导通模式下,所提新型变换器的工作原理及运行特性进行相关分析。通过搭建400 V/200 W实验样机,验证了该文提出的拓扑结构在外部升压的工况下可实现较高的电压增益。 展开更多
关键词 dc-dc变换器 SEPIC变换器 高增益 级联 低电压应力
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Hydrophobic surface release and energy-level alignment of PTAA enables stable flexible perovskite solar modules
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作者 Hua Zhong Jianxing Xia +2 位作者 Hao Tian Chuanxiao Xiao Fei Zhang 《Journal of Energy Chemistry》 2025年第10期448-454,共7页
The fabrication of efficient and stable flexible perovskite solar modules(F-PSMs)using poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine](PTAA)remains a significant challenge due to its hydrophobic properties and the mis... The fabrication of efficient and stable flexible perovskite solar modules(F-PSMs)using poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine](PTAA)remains a significant challenge due to its hydrophobic properties and the mismatch in interface energy-level alignment.Here,we introduced[2-(3,6-dimethoxy-9H-carba zol-9-yl)ethyl]phosphonic acid(MeO-2PACz)to modify the PTAA layer,which effectively suppressed surface potential fluctuations and aligned energy levels at the interface of PTAA/perovskite.Additionally,MeO-2PACz enhanced the hydrophilicity of PTAA,facilitating the fabrication of dense,uniform,and pinhole-free perovskite films on large-area flexible substrates.As a result,we achieved an F-PSM with a power conversion efficiency(PCE)of 16.6% and an aperture area of 64 cm^(2),which is the highest reported value among F-PSMs with an active area exceeding 35 cm^(2)based on PTAA.Moreover,the encapsulated module demonstrated outstanding long-term operational stability,retaining 90.2% of its initial efficiency after 1000 bending cycles(5 mm radius),87.2% after 1000 h of continuous illumination,and 80.3% under combined thermal and humid conditions(85℃ and 85% relative humidity),representing one of the most stable F-PSMs reported to date. 展开更多
关键词 FLEXIBLE Perovskite solar modules STABILITY
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Two-tailed modification module tuned steric-hindrance effect enabling high therapeutic efficacy of paclitaxel prodrug nanoassemblies
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作者 Wenfeng Zang Yixin Sun +9 位作者 Jingyi Zhang Yanzhong Hao Qianhui Jin Hongying Xiao Zuo Zhang Xianbao Shi Jin Sun Zhonggui He Cong Luo Bingjun Sun 《Chinese Chemical Letters》 2025年第5期453-459,共7页
Self-assembled prodrug nanomedicine has emerged as an advanced platform for antitumor therapy,mainly comprise drug modules,response modules and modification modules.However,existing studies usually compare the differe... Self-assembled prodrug nanomedicine has emerged as an advanced platform for antitumor therapy,mainly comprise drug modules,response modules and modification modules.However,existing studies usually compare the differences between single types of modification modules,neglecting the impact of steric-hindrance effect caused by chemical structure.Herein,single-tailed modification module with low-steric-hindrance effect and two-tailed modification module with high-steric-hindrance effect were selected to construct paclitaxel prodrugs(P-LA_(C18)and P-BAC18),and the in-depth insights of the sterichindrance effect on prodrug nanoassemblies were explored.Notably,the size stability of the two-tailed prodrugs was enhanced due to improved intermolecular interactions and steric hindrance.Single-tailed prodrug nanoassemblies were more susceptible to attack by redox agents,showing faster drug release and stronger antitumor efficacy,but with poorer safety.In contrast,two-tailed prodrug nanoassemblies exhibited significant advantages in terms of pharmacokinetics,tumor accumulation and safety due to the good size stability,thus ensuring equivalent antitumor efficacy at tolerance dose.These findings highlighted the critical role of steric-hindrance effect of the modification module in regulating the structureactivity relationship of prodrug nanoassemblies and proposed new perspectives into the precise design of self-assembled prodrugs for high-performance cancer therapeutics. 展开更多
关键词 Prodrug nanoassemblies Two-tailed modification module Steric-hindrance PACLITAXEL Anticancer
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