针对复合材料电池包下箱体的树脂传递模塑(Resin Transfer Molding,RTM)成型进行了方案设计,基于PAM-RTM软件对其充模过程进行仿真分析及孔隙缺陷预测。首先,对比了两种方案在三种出胶口状态下充模时间,分析了注胶压力及树脂黏度对RTM...针对复合材料电池包下箱体的树脂传递模塑(Resin Transfer Molding,RTM)成型进行了方案设计,基于PAM-RTM软件对其充模过程进行仿真分析及孔隙缺陷预测。首先,对比了两种方案在三种出胶口状态下充模时间,分析了注胶压力及树脂黏度对RTM成型时间的影响规律;其次,分析了充模过程中注胶口附近位置的压力变化情况;最后,预测了宏观/微观两种尺度孔隙缺陷在构件中分布及注胶压力对孔隙含量的影响规律,并结合流速优化理论控制树脂前沿流速以降低孔隙含量。结果表明,模腔内注胶与出胶口压力差越大,成型用时越少,且受到注胶位置影响。注胶压力与充模时间呈线性关系,压力越低,充模时间缩短效果越明显,且黏度越大,充模时间越长。孔隙含量与前沿流速有关,注胶压力越大导致流速越快,宏观孔隙随之减少,微观孔隙相应增多;且流速优化方式注胶能够显著降低总体孔隙率水平,但会延长成型周期。展开更多
树脂传递模塑成型(Resin transfer molding,RTM)工艺仿真对于提高成型质量,降低RTM工艺成本至关重要。将人工智能方法引入RTM工艺仿真中,可以不必求解复杂的多尺度渗流模型就能够获得对RTM模具设计的指导性意见。本文综述了以遗传算法...树脂传递模塑成型(Resin transfer molding,RTM)工艺仿真对于提高成型质量,降低RTM工艺成本至关重要。将人工智能方法引入RTM工艺仿真中,可以不必求解复杂的多尺度渗流模型就能够获得对RTM模具设计的指导性意见。本文综述了以遗传算法和机器学习方法为主的人工智能方法在RTM工艺仿真中的研究现状,并讨论了该领域存在的问题及发展方向。遗传算法主要被应用于注胶口及流道配置优化方面,但在复杂问题中收敛性较差,与其他局部搜索算法结合的方法展现出解决复杂问题的潜力;机器学习方法的应用研究处于起步阶段,目前主要被应用于注射压力、浸渍质量、渗透率预测等方面,只对简单二维充模问题进行了研究;其他人工智能方法通常计算成本低,但难以验证最优性。人工智能方法的问题集中在迭代/训练所需的数据集的获取成本方面。其在三维复杂几何结构及非均匀渗透率制件方面的应用是未来的重要发展方向。展开更多
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
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
本文公开了一种适用于HP-RTM(High Pressure Resin Transfer Molding)工艺的高强度阻燃环氧树脂组合物,包含A、B两个组分,其中A组分包含基体树脂、阻燃剂、稀释剂和助剂,B组分包含胺类固化剂和促进剂,阻燃剂为磷酸酯类化合物和四溴双酚...本文公开了一种适用于HP-RTM(High Pressure Resin Transfer Molding)工艺的高强度阻燃环氧树脂组合物,包含A、B两个组分,其中A组分包含基体树脂、阻燃剂、稀释剂和助剂,B组分包含胺类固化剂和促进剂,阻燃剂为磷酸酯类化合物和四溴双酚A环氧树脂的组合物。研究了基体树脂、阻燃剂、稀释剂的种类和含量对HP-RTM环氧树脂强度和阻燃性的影响,以及胺类固化剂的种类和含量对HP-RTM环氧树脂凝胶时间的影响。结果表明,基体树脂、反应型阻燃剂、稀释剂对力学强度共同影响,阻燃剂对阻燃性能起主要影响作用,固化剂对凝胶时间起主要影响作用。展开更多
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
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
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
文摘针对复合材料电池包下箱体的树脂传递模塑(Resin Transfer Molding,RTM)成型进行了方案设计,基于PAM-RTM软件对其充模过程进行仿真分析及孔隙缺陷预测。首先,对比了两种方案在三种出胶口状态下充模时间,分析了注胶压力及树脂黏度对RTM成型时间的影响规律;其次,分析了充模过程中注胶口附近位置的压力变化情况;最后,预测了宏观/微观两种尺度孔隙缺陷在构件中分布及注胶压力对孔隙含量的影响规律,并结合流速优化理论控制树脂前沿流速以降低孔隙含量。结果表明,模腔内注胶与出胶口压力差越大,成型用时越少,且受到注胶位置影响。注胶压力与充模时间呈线性关系,压力越低,充模时间缩短效果越明显,且黏度越大,充模时间越长。孔隙含量与前沿流速有关,注胶压力越大导致流速越快,宏观孔隙随之减少,微观孔隙相应增多;且流速优化方式注胶能够显著降低总体孔隙率水平,但会延长成型周期。
文摘树脂传递模塑成型(Resin transfer molding,RTM)工艺仿真对于提高成型质量,降低RTM工艺成本至关重要。将人工智能方法引入RTM工艺仿真中,可以不必求解复杂的多尺度渗流模型就能够获得对RTM模具设计的指导性意见。本文综述了以遗传算法和机器学习方法为主的人工智能方法在RTM工艺仿真中的研究现状,并讨论了该领域存在的问题及发展方向。遗传算法主要被应用于注胶口及流道配置优化方面,但在复杂问题中收敛性较差,与其他局部搜索算法结合的方法展现出解决复杂问题的潜力;机器学习方法的应用研究处于起步阶段,目前主要被应用于注射压力、浸渍质量、渗透率预测等方面,只对简单二维充模问题进行了研究;其他人工智能方法通常计算成本低,但难以验证最优性。人工智能方法的问题集中在迭代/训练所需的数据集的获取成本方面。其在三维复杂几何结构及非均匀渗透率制件方面的应用是未来的重要发展方向。
文摘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.
基金supported by National Science and Technology Council(NSTC)Taiwan,Grant No.NSTC 113-2221-E-167-023.
文摘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.
文摘本文公开了一种适用于HP-RTM(High Pressure Resin Transfer Molding)工艺的高强度阻燃环氧树脂组合物,包含A、B两个组分,其中A组分包含基体树脂、阻燃剂、稀释剂和助剂,B组分包含胺类固化剂和促进剂,阻燃剂为磷酸酯类化合物和四溴双酚A环氧树脂的组合物。研究了基体树脂、阻燃剂、稀释剂的种类和含量对HP-RTM环氧树脂强度和阻燃性的影响,以及胺类固化剂的种类和含量对HP-RTM环氧树脂凝胶时间的影响。结果表明,基体树脂、反应型阻燃剂、稀释剂对力学强度共同影响,阻燃剂对阻燃性能起主要影响作用,固化剂对凝胶时间起主要影响作用。
基金financial support from the National Natural Science Foundation of China(Nos.52204089,52374082)the Young Elite Scientists Sponsorship Program(No.2023QNRC001)by China Association for Science and Technology(CAST).
文摘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.
基金supported by the Gansu Provincial Department of Education Industry Support Plan Project(2025CYZC-018).
文摘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.
基金Supported by Anhui Provincial Engineering Research Center for Sports and Health Information Monitoring Technology(KF2023012)。
文摘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.
