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Tea Leaf Disease Diagnosis Based on Improved Lightweight U-Net3+
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作者 HU Yumeng GUAN Feifan +5 位作者 XIE Dongchen MA Ping YU Youben ZHOU Jie NIE Yanming HUANG Lüwen 《智慧农业(中英文)》 2026年第1期15-27,共13页
[Objective]Leaf diseases significantly affect both the yield and quality of tea throughout the year.To address the issue of inadequate segmentation finesse in the current tea spot segmentation models,a novel diagnosis... [Objective]Leaf diseases significantly affect both the yield and quality of tea throughout the year.To address the issue of inadequate segmentation finesse in the current tea spot segmentation models,a novel diagnosis of the severity of tea spots was proposed in this research,designated as MDC-U-Net3+,to enhance segmentation accuracy on the base framework of U-Net3+.[Methods]Multi-scale feature fusion module(MSFFM)was incorporated into the backbone network of U-Net3+to obtain feature information across multiple receptive fields of diseased spots,thereby reducing the loss of features within the encoder.Dual multi-scale attention(DMSA)was incorporated into the skip connection process to mitigate the segmentation boundary ambiguity issue.This integration facilitates the comprehensive fusion of fine-grained and coarse-grained semantic information at full scale.Furthermore,the segmented mask image was subjected to conditional random fields(CRF)to enhance the optimization of the segmentation results[Results and Discussions]The improved model MDC-U-Net3+achieved a mean pixel accuracy(mPA)of 94.92%,accompanied by a mean Intersection over Union(mIoU)ratio of 90.9%.When compared to the mPA and mIoU of U-Net3+,MDC-U-Net3+model showed improvements of 1.85 and 2.12 percentage points,respectively.These results illustrated a more effective segmentation performance than that achieved by other classical semantic segmentation models.[Conclusions]The methodology presented herein could provide data support for automated disease detection and precise medication,consequently reducing the losses associated with tea diseases. 展开更多
关键词 disease diagnosis semantic segmentation u-net3+ multi-scale feature fusion attention mechanism conditional random fields
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A Novel Improved Puma Optimizer to Boost Photovoltaic Array Production in Partially Shaded Environments
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作者 Nagwan Abdel Samee Ahmed Fathy +2 位作者 Mohamed A.Mahdy Maali Alabdulhafith Essam H.Houssein 《Computer Modeling in Engineering & Sciences》 2026年第2期737-771,共35页
This research proposes an improved Puma optimization algorithm(IPuma)as a novel dynamic recon-figuration tool for a photovoltaic(PV)array linked in total-cross-tied(TCT).The proposed algorithm utilizes the Newton-Raph... This research proposes an improved Puma optimization algorithm(IPuma)as a novel dynamic recon-figuration tool for a photovoltaic(PV)array linked in total-cross-tied(TCT).The proposed algorithm utilizes the Newton-Raphson search rule(NRSR)to boost the exploration process,especially in search spaces with more local regions,and boost the exploitation with adaptive parameters alternating with random parameters in the original Puma.The effectiveness of the introduced IPuma is confirmed through comprehensive evaluations on the CEC’20 benchmark problems.It shows superior performance compared to both established and modern metaheuristic algorithms in terms of effectively navigating the search space and achieving convergence towards near-optimal regions.The findings indicated that the IPuma algorithm demonstrates considerable statistical promise and surpasses the performance of competing algorithms.In addition,the proposed IPuma is utilized to reconfigure a 9×9 PV array that operates under different shade patterns,such as lower triangular(LT),long wide(LW),and short wide(SW).In addition to other programmed approaches,such as the Whale optimization algorithm(WOA),grey wolf optimizer(GWO),Harris Hawks optimization(HHO),particle swarm optimization(PSO),gravitational search algorithm(GSA),biogeography-based optimization(BBO),sine cosine algorithm(SCA),equilibrium optimizer(EO),and original Puma,the indicated method is contrasted to the traditional configurations of TCT and Sudoku.In addition,the metrics of mismatch power loss,maximum efficiency improvement,efficiency improvement ratio,and peak-to-mean ratio are calculated to assess the effectiveness of the indicated approach.The proposed IPuma improved the generated power by 36.72%,28.03%,and 40.97%for SW,LW,and LT,respectively,outperforming the TCT configuration.In addition,it achieved the best maximum efficiency improvement among the algorithms considered,with 26.86%,21.89%,and 29.07%for the examined patterns.The results highlight the superiority and competence of the proposed approach in both convergence rates and stability,as well as applicability to dynamically reconfigure the PV system and enhance its harvested energy. 展开更多
关键词 Photovoltaic partial shade RECONFIGURATION improved puma METAHEURISTIC
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PEMFC Performance Degradation Prediction Based on CNN-BiLSTM with Data Augmentation by an Improved GAN
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作者 Xiaolu Wang Haoyu Sun +1 位作者 Aiguo Wang Xin Xia 《Energy Engineering》 2026年第2期417-435,共19页
To address the issues of insufficient and imbalanced data samples in proton exchange membrane fuel cell(PEMFC)performance degradation prediction,this study proposes a data augmentation-based model to predict PEMFC per... To address the issues of insufficient and imbalanced data samples in proton exchange membrane fuel cell(PEMFC)performance degradation prediction,this study proposes a data augmentation-based model to predict PEMFC performance degradation.Firstly,an improved generative adversarial network(IGAN)with adaptive gradient penalty coefficient is proposed to address the problems of excessively fast gradient descent and insufficient diversity of generated samples.Then,the IGANis used to generate datawith a distribution analogous to real data,therebymitigating the insufficiency and imbalance of original PEMFC samples and providing the predictionmodel with training data rich in feature information.Finally,a convolutional neural network-bidirectional long short-termmemory(CNN-BiLSTM)model is adopted to predict PEMFC performance degradation.Experimental results show that the data generated by the proposed IGAN exhibits higher quality than that generated by the original GAN,and can fully characterize and enrich the original data’s features.Using the augmented data,the prediction accuracy of the CNN-BiLSTM model is significantly improved,rendering it applicable to tasks of predicting PEMFC performance degradation. 展开更多
关键词 PEMFC performance degradation prediction data augmentation improved generative adversarial network
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Harness the wild:progress and perspectives in wheat genetic improvement
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作者 Xiubin Tian Ziyu Wang +1 位作者 Wenxuan Liu Yusheng Zhao 《Journal of Genetics and Genomics》 2026年第1期1-15,共15页
Bread wheat(Triticum aestivum L.)is a staple hexaploid crop with numerous wild relatives.However,domestication and modern breeding have significantly narrowed its genetic diversity,diminishing its capacity to adapt to... Bread wheat(Triticum aestivum L.)is a staple hexaploid crop with numerous wild relatives.However,domestication and modern breeding have significantly narrowed its genetic diversity,diminishing its capacity to adapt to climate change.Wild relatives of wheat serve as a vital reservoir of genetic diversity,offering traits thatenhance its resistance to various biotic and abiotic stresses.Over recent decades,remarkable progress has been made in utilizing superior genes from wild relatives to bolster wheat's defenses against diseases and pests,though the exploration of genes conferring abiotic stress tolerance has lagged behind.In this review,we summarize key advancements in the utilization of wild relatives for wheat enhancement over the past century,emphasizing both theoretical and technological innovations.Furthermore,we evaluate the potential contributions of wild relatives to address production challenges posed by climate change.We also explore strategies for isolating superior genes and developing prebreeding germplasm to support the future development of climate-resilient wheat varieties. 展开更多
关键词 Bread wheat Wild relatives Biotic stress Abiotic stress Genetic improvement Climate change
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Quantitative Detection of Micro Hole Wall Roughness in PCBs Based on Improved U-Net Model
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作者 Lijuan Zheng Yonghao Li +5 位作者 Zhuangzhuang Sun Yangquan Luo Ying Xu Jun Wang Chengyong Wang Xin Wei 《Chinese Journal of Mechanical Engineering》 2025年第3期1-11,共11页
The current method for inspecting microholes in printed circuit boards(PCBs)involves preparing slices followed by optical microscope measurements.However,this approach suffers from low detection efficiency,poor reliab... The current method for inspecting microholes in printed circuit boards(PCBs)involves preparing slices followed by optical microscope measurements.However,this approach suffers from low detection efficiency,poor reliability,and insufficient measurement stability.Micro-CT enables the observation of the internal structures of the sample without the need for slicing,thereby presenting a promising new method for assessing the quality of microholes in PCBs.This study integrates computer vision technology with computed tomography(CT)to propose a method for detecting microhole wall roughness using a U-Net model and image processing algorithms.This study established an unplated copper PCB CT image dataset and trained an improved U-Net model.Validation of the test set demonstrated that the improved model effectively segmented microholes in the PCB CT images.Subsequently,the roughness of the holes’walls was assessed using a customized image-processing algorithm.Comparative analysis between CT detection based on various edge detection algorithms and slice detection revealed that CT detection employing the Canny algorithm closely approximates slice detection,yielding range and average errors of 2.92 and 1.64μm,respectively.Hence,the detection method proposed in this paper offers a novel approach for nondestructive testing of hole wall roughness in the PCB industry. 展开更多
关键词 PCB CT image segmentation improved u-net model Hole wall roughness Micro-CT non-destructive testing
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Performance improvement method of new R&D institutions considering Bayesian network
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作者 ZHU Jianjun JIANG Lin 《Journal of Systems Engineering and Electronics》 2026年第1期257-271,共15页
A performance improvement model of research and development(R&D)institutions based on evolutionary game and Bayesian network is proposed.First,the nature and performance factors of new R&D institutions are sys... A performance improvement model of research and development(R&D)institutions based on evolutionary game and Bayesian network is proposed.First,the nature and performance factors of new R&D institutions are systematically analyzed,the appropriate factor model is found,and the sharing of performance benefits between institutions and employees,the change in distribution proportion,and the risk of institutional improvement and employee cooperation are considered.Second,based on the mechanism improvement and employee cooperation,the payment matrix is given and evolutionary game analysis is carried out to obtain a stable and balanced institutional improvement probability and employee cooperation probability.These two probability values are substituted into the Bayesian network model of performance improvement of new R&D institutions,and the posterior probability of performance improvement is predicted by Bayesian network reasoning and diagnosis to find effective improvement measures.Finally,practical case analysis is given to verify the effectiveness and practicability of the proposed method. 展开更多
关键词 new research and development(R&D)institution performance improvement evolutionary game Bayesian network conditional probability
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An improved conditional denoising diffusion GAN for Mach number field reconstruction in a multi-tunnel combined inlet based on sparse parameter information
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作者 Ke MIN Fan LEI +2 位作者 Jiale ZHANG Chengxiang ZHU Yancheng YOU 《Chinese Journal of Aeronautics》 2026年第1期169-190,共22页
The internal flow fields within a three-dimensional inward-tunning combined inlet are extremely complex,especially during the engine mode transition,where the tunnel changes may impact the flow fields significantly.To... The internal flow fields within a three-dimensional inward-tunning combined inlet are extremely complex,especially during the engine mode transition,where the tunnel changes may impact the flow fields significantly.To develop an efficient flow field reconstruction model for this,we present an Improved Conditional Denoising Diffusion Generative Adversarial Network(ICDDGAN),which integrates Conditional Denoising Diffusion Probabilistic Models(CDDPMs)with Style GAN,and introduce a reconstruction discrimination mechanism and dynamic loss weight learning strategy.We establish the Mach number flow field dataset by numerical simulation at various backpressures for the mode transition process from turbine mode to ejector ramjet mode at Mach number 2.5.The proposed ICDDGAN model,given only sparse parameter information,can rapidly generate high-quality Mach number flow fields without a large number of samples for training.The results show that ICDDGAN is superior to CDDGAN in terms of training convergence and stability.Moreover,the interpolation and extrapolation test results during backpressure conditions show that ICDDGAN can accurately and quickly reconstruct Mach number fields at various tunnel slice shapes,with a Structural Similarity Index Measure(SSIM)of over 0.96 and a Mean-Square Error(MSE)of 0.035%to actual flow fields,reducing time costs by 7-8 orders of magnitude compared to Computational Fluid Dynamics(CFD)calculations.This can provide an efficient means for rapid computation of complex flow fields. 展开更多
关键词 Flow field reconstruction improved Conditional Denoising Diffusion Generative Adversarial Network(ICDDGAN) Mode transition Sparse parameter information Three-dimensional inward-tunning combined inlet
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Enhancing 3D U-Net with Residual and Squeeze-and-Excitation Attention Mechanisms for Improved Brain Tumor Segmentation in Multimodal MRI
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作者 Yao-Tien Chen Nisar Ahmad Khursheed Aurangzeb 《Computer Modeling in Engineering & Sciences》 2025年第7期1197-1224,共28页
Accurate and efficient brain tumor segmentation is essential for early diagnosis,treatment planning,and clinical decision-making.However,the complex structure of brain anatomy and the heterogeneous nature of tumors pr... Accurate and efficient brain tumor segmentation is essential for early diagnosis,treatment planning,and clinical decision-making.However,the complex structure of brain anatomy and the heterogeneous nature of tumors present significant challenges for precise anomaly detection.While U-Net-based architectures have demonstrated strong performance in medical image segmentation,there remains room for improvement in feature extraction and localization accuracy.In this study,we propose a novel hybrid model designed to enhance 3D brain tumor segmentation.The architecture incorporates a 3D ResNet encoder known for mitigating the vanishing gradient problem and a 3D U-Net decoder.Additionally,to enhance the model’s generalization ability,Squeeze and Excitation attention mechanism is integrated.We introduce Gabor filter banks into the encoder to further strengthen the model’s ability to extract robust and transformation-invariant features from the complex and irregular shapes typical in medical imaging.This approach,which is not well explored in current U-Net-based segmentation frameworks,provides a unique advantage by enhancing texture-aware feature representation.Specifically,Gabor filters help extract distinctive low-level texture features,reducing the effects of texture interference and facilitating faster convergence during the early stages of training.Our model achieved Dice scores of 0.881,0.846,and 0.819 for Whole Tumor(WT),Tumor Core(TC),and Enhancing Tumor(ET),respectively,on the BraTS 2020 dataset.Cross-validation on the BraTS 2021 dataset further confirmed the model’s robustness,yielding Dice score values of 0.887 for WT,0.856 for TC,and 0.824 for ET.The proposed model outperforms several state-of-the-art existing models,particularly in accurately identifying small and complex tumor regions.Extensive evaluations suggest integrating advanced preprocessing with an attention-augmented hybrid architecture offers significant potential for reliable and clinically valuable brain tumor segmentation. 展开更多
关键词 3D MRI artificial intelligence deep learning AI in healthcare attention mechanism u-net medical image analysis brain tumor segmentation BraTS 2021 BraTS 2020
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基于改进U-Net的铜合金晶界识别方法
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作者 靖青秀 刘卫辉 +4 位作者 常琪琪 谢伟滨 张志聪 吴瑞洋 黄晓东 《有色金属(中英文)》 北大核心 2026年第2期198-206,共9页
晶粒度评级精度高度依赖于准确的晶粒尺寸与形状表征,而晶界分割是界定晶粒范围的关键预处理步骤。针对铜合金显微图像中晶界对比度低、边缘模糊导致的检测困难,以及现有高精度分割算法参数量大、计算复杂度高、难以满足工业实时检测需... 晶粒度评级精度高度依赖于准确的晶粒尺寸与形状表征,而晶界分割是界定晶粒范围的关键预处理步骤。针对铜合金显微图像中晶界对比度低、边缘模糊导致的检测困难,以及现有高精度分割算法参数量大、计算复杂度高、难以满足工业实时检测需求等问题,本文提出一种基于MobileNetV2的轻量化U-Net改进方法。通过将MobileNetV2作为主干网络解决特征丢失问题,并引入集成深度可分离卷积的ASPP模块,有效增强了多尺度语义特征提取能力。实验结果表明,改进后的模型在保持轻量化的同时,在晶界分割任务中取得了mIOU 87.66%、精确率93.50%、平均像素准确率92.79%的优异性能,显著优于传统U-Net模型,为工业现场实时晶界识别提供了可靠解决方案。 展开更多
关键词 铜合金 晶粒度 深度学习 u-net 轻量化
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基于多尺度特征提取的U-Net网络微地震定位方法
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作者 黄建平 王秋阳 +6 位作者 李媛媛 黎国龙 苏来源 路依霖 李三福 段文胜 雷刚林 《中国石油大学学报(自然科学版)》 北大核心 2026年第1期1-11,共11页
微地震定位是微地震监测的核心任务,面对当前海量的地震数据,传统的定位方法已无法满足实时定位的需求。为此,利用深度学习技术,提出一种基于U-Net网络为主要架构的微地震震源定位方法,通过融合双交叉注意力模块和空间空洞金字塔池化模... 微地震定位是微地震监测的核心任务,面对当前海量的地震数据,传统的定位方法已无法满足实时定位的需求。为此,利用深度学习技术,提出一种基于U-Net网络为主要架构的微地震震源定位方法,通过融合双交叉注意力模块和空间空洞金字塔池化模块,增强网络对微震数据中波形特征的提取能力,提升震源位置预测精度。最后,利用简单层状和复杂速度模型生成合成数据进行实验测试,并与U-Net和Att-Unet网络对震源位置预测误差精度进行对比分析。结果表明,所构建的网络模型在震源预测精度以及网络性能上均优于其他网络模型,并且对低信噪比的微地震数据也有较好的预测效果。 展开更多
关键词 微震定位 水力压裂 多尺度特征提取 u-net网络 注意力机制
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基于改进U-Net网络和知识蒸馏的三维断层识别方法
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作者 王莉利 梁云虎 高新成 《石油物探》 北大核心 2026年第1期21-30,共10页
深度学习方法在三维地震资料断层识别中得到了广泛应用,但方法的应用面临数据集质量欠佳、资源消耗过高以及训练周期长等问题。为此,提出了一种融合改进U-Net网络和知识蒸馏的三维断层识别方法。该方法先将改进的U-Net网络模型作为教师... 深度学习方法在三维地震资料断层识别中得到了广泛应用,但方法的应用面临数据集质量欠佳、资源消耗过高以及训练周期长等问题。为此,提出了一种融合改进U-Net网络和知识蒸馏的三维断层识别方法。该方法先将改进的U-Net网络模型作为教师模型,将空洞空间金字塔池化(ASPP)结构与U-Net网络模型相融合,构建轻量级学生模型,然后引入知识蒸馏技术对学生模型进行优化,并调整网络训练超参数和知识蒸馏损失参数,使学生模型获取更丰富的断层信息,提升学生模型的网络性能。该方法通过将复杂的教师模型的知识迁移到轻量级学生模型,显著降低了模型的计算复杂度,同时保持了较高的识别精度。测试结果表明,在合成测试集和实际地震数据的断层识别中,经过知识蒸馏训练的学生模型在识别精度和连续性上均优于未经过蒸馏的学生模型和单独训练的教师模型,充分验证了方法的可行性和有效性。 展开更多
关键词 断层识别 知识蒸馏 u-net 教师模型 学生模型
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融合对抗自编码器和U-net的非侵入式负荷分解方法
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作者 王凌云 朱倍萱 +1 位作者 张涛 罗明天 《电力系统及其自动化学报》 北大核心 2026年第2期59-68,共10页
为了提高非侵入式负荷分解模型的分解效果和泛化性能,并针对现有生成式模型在非侵入式负荷分解任务中存在的一些局限性,提出一种引入变分推理思想和联合对抗机制的对抗自编码器非侵入式负荷分解方法。为保证负荷分解的实时性,采用序列... 为了提高非侵入式负荷分解模型的分解效果和泛化性能,并针对现有生成式模型在非侵入式负荷分解任务中存在的一些局限性,提出一种引入变分推理思想和联合对抗机制的对抗自编码器非侵入式负荷分解方法。为保证负荷分解的实时性,采用序列到序列映射模型。基于U-net框架构建对抗自编码器模型,在编码器与解码器之间添加跳跃连接,使模型可以同时捕获电器特征的局部细节和全局信息,实现多特征融合,避免特征丢失,同时引入实例-批归一化网络,提高模型的分解性能以及泛化性能。最后将所提模型与几种代表性模型在UK-DALE数据集上进行对比实验。结果表明:所提模型具有优秀的分解性能和泛化能力,并且更加轻量化。 展开更多
关键词 非侵入式负荷分解 对抗自编码器 深度学习 序列到序列 u-net 实例-批归一化
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Application of the improved dung beetle optimizer,muti-head attention and hybrid deep learning algorithms to groundwater depth prediction in the Ningxia area,China 被引量:1
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作者 Jiarui Cai Bo Sun +5 位作者 Huijun Wang Yi Zheng Siyu Zhou Huixin Li Yanyan Huang Peishu Zong 《Atmospheric and Oceanic Science Letters》 2025年第1期18-23,共6页
Due to the lack of accurate data and complex parameterization,the prediction of groundwater depth is a chal-lenge for numerical models.Machine learning can effectively solve this issue and has been proven useful in th... Due to the lack of accurate data and complex parameterization,the prediction of groundwater depth is a chal-lenge for numerical models.Machine learning can effectively solve this issue and has been proven useful in the prediction of groundwater depth in many areas.In this study,two new models are applied to the prediction of groundwater depth in the Ningxia area,China.The two models combine the improved dung beetle optimizer(DBO)algorithm with two deep learning models:The Multi-head Attention-Convolution Neural Network-Long Short Term Memory networks(MH-CNN-LSTM)and the Multi-head Attention-Convolution Neural Network-Gated Recurrent Unit(MH-CNN-GRU).The models with DBO show better prediction performance,with larger R(correlation coefficient),RPD(residual prediction deviation),and lower RMSE(root-mean-square error).Com-pared with the models with the original DBO,the R and RPD of models with the improved DBO increase by over 1.5%,and the RMSE decreases by over 1.8%,indicating better prediction results.In addition,compared with the multiple linear regression model,a traditional statistical model,deep learning models have better prediction performance. 展开更多
关键词 Groundwater depth Multi-head attention improved dung beetle optimizer CNN-LSTM CNN-GRU Ningxia
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Improved methods,properties,applications and prospects of microbial induced carbonate precipitation(MICP)treated soil:A review 被引量:2
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作者 Xuanshuo Zhang Hongyu Wang +3 位作者 Ya Wang Jinghui Wang Jing Cao Gang Zhang 《Biogeotechnics》 2025年第1期34-54,共21页
Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vi... Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vironment and intensify carbon emissions.However,the use of microbially induced calcium carbonate pre-cipitation(MICP)to obtain bio-cement is a novel technique with the potential to induce soil stability,providing a low-carbon,environment-friendly,and sustainable integrated solution for some geotechnical engineering pro-blems in the environment.This paper presents a comprehensive review of the latest progress in soil improvement based on the MICP strategy.It systematically summarizes and overviews the mineralization mechanism,influ-encing factors,improved methods,engineering characteristics,and current field application status of the MICP.Additionally,it also explores the limitations and correspondingly proposes prospective applications via the MICP approach for soil improvement.This review indicates that the utilization of different environmental calcium-based wastes in MICP and combination of materials and MICP are conducive to meeting engineering and market demand.Furthermore,we recommend and encourage global collaborative study and practice with a view to commercializing MICP technique in the future.The current review purports to provide insights for engineers and interdisciplinary researchers,and guidance for future engineering applications. 展开更多
关键词 Soil improvement Bio-cement MICP improved methods Field application cases
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融合多源特征与注意力机制的改进U-Net鱼鳞坑遥感提取方法
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作者 魏敬志 黄骁力 +4 位作者 江岭 梁明 张大鹏 王莎莎 宋音 《农业工程学报》 北大核心 2026年第2期214-224,共11页
鱼鳞坑是黄土高原典型的小型水土保持措施,由于其尺度小、分布不均,传统卫星遥感方法难以实现高精度识别。为此,该研究提出一种融合多源特征与注意力机制的深度学习鱼鳞坑遥感提取方法,构建了“特征重要性分析+注意力增强U-Net结构设计... 鱼鳞坑是黄土高原典型的小型水土保持措施,由于其尺度小、分布不均,传统卫星遥感方法难以实现高精度识别。为此,该研究提出一种融合多源特征与注意力机制的深度学习鱼鳞坑遥感提取方法,构建了“特征重要性分析+注意力增强U-Net结构设计”的技术框架。基于无人机获取的高分辨率多光谱影像与数字高程模型(digital elevation model,DEM),该研究综合运用Spearman相关系数与SHAP(Shapley additive explanations)可解释性分析方法,对光谱与地形特征进行重要性评估与冗余剔除,最终优选出4类关键特征,并据此设计了9种特征组合方案。在此基础上,采用UNet、DeepLabV3+、SegNet与FCN四种语义分割模型开展对比试验,结果表明以RGB+Slope的特征组合方案在UNet模型中识别效果最优。在模型结构方面,该研究以U-Net为基础,融合金字塔压缩注意力模块(pyramid squeeze attention module,PSAM)与多级特征注意力上采样模块(multi-scale feature attention upsampling module,MFAU),增强模型对鱼鳞坑边缘与空间结构的感知能力,并设计消融试验验证改进效果。试验结果表明,在最优特征组合的数据输入下,改进模型在测试区交并比提升2.47个百分点,F1分数提升1.34个百分点,召回率提升2.72个百分点,精确率提升1.02个百分点,表现出良好的提取精度与区域泛化能力。研究表明,特征重要性分析与注意力增强结构设计的融合策略可有效提升模型对小尺度地貌目标的识别性能,为鱼鳞坑等微地形构筑物的高精度遥感提取提供技术支撑,也为多源信息融合与深度学习模型构建提供了理论参考。 展开更多
关键词 无人机 遥感 语义分割 鱼鳞坑提取 u-net改进 注意力机制
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基于改进U-Net的人工光植物工厂生菜图像分割方法
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作者 李文豪 金文帅 +3 位作者 高晟 薛岳 毛罕平 左志宇 《农机化研究》 北大核心 2026年第6期157-163,共7页
针对植物工厂内作物在人工光环境下图像分割精度不足的问题,提出了一种改进的U-Net神经网络模型,以实现对作物图像的高精度分割。首先通过对比试验,系统比较了传统图像分割方法(如阈值、聚类和区域等)与神经网络方法在人工光环境下的分... 针对植物工厂内作物在人工光环境下图像分割精度不足的问题,提出了一种改进的U-Net神经网络模型,以实现对作物图像的高精度分割。首先通过对比试验,系统比较了传统图像分割方法(如阈值、聚类和区域等)与神经网络方法在人工光环境下的分割效果,结果表明:与传统方法相比,U-Net神经网络在分割精度和模型稳定性方面具有明显优势。然而,进一步分析U-Net模型的分割结果发现,其在复杂光照条件下的分割精度和泛化能力仍有提升空间,主要体现在边界细节处理和小目标分割的准确性不足。为此,针对性地提出3种改进策略:一是通过数据增强技术扩展训练数据集,以提升模型的鲁棒性;二是对U-Net模型的结构进行优化,改进金字塔结构以增强多尺度特征融合能力;三是采用坐标注意力机制,有效提升模型对目标区域的聚焦能力,特别是在背景复杂或光线不均的情况下。基于此,进行试验验证,结果表明:结合改进金字塔结构和坐标注意力机制的U-Net模型在分割平均精确率和平均交并比上分别达到98.19%和96.86%,相比原始U-Net模型分别提高了4.01、3.02个百分点。所提方法显著改善了人工光环境下对植物工厂作物的图像分割性能,为植物工厂内作物生长监测与精准信息采集提供了技术支持,同时为未来智能农业领域的相关研究奠定了基础。 展开更多
关键词 生菜图像分割 植物工厂 人工光 改进u-net 注意力机制 神经网络
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The genetic basis and improvement of photosynthesis in tomato 被引量:1
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作者 Haiqiang Dong Fangman Li +7 位作者 Xiaoxiao Xuan John Kojo Ahiakpa Jinbao Tao Xingyu Zhang Pingfei Ge Yaru Wang Wenxian Gai Yuyang Zhang 《Horticultural Plant Journal》 2025年第1期69-84,共16页
Photosynthesis is one the most important chemical reaction in plants,and it is the ultimate energy source of any living organisms.The light and dark reactions are two essential phases of photosynthesis.Light reaction ... Photosynthesis is one the most important chemical reaction in plants,and it is the ultimate energy source of any living organisms.The light and dark reactions are two essential phases of photosynthesis.Light reaction harvests light energy to synthesize ATP and NADPH through an electron transport chain,and as well as giving out O_(2);dark reaction fixes CO_(2) into six carbon sugars by utilizing NADPH and energy from ATP.Subsequently,plants convert optical energy into chemical energy for maintaining growth and development through absorbing light energy.Here,firstly,we highlighted the biological importance of photosynthesis,and hormones and metabolites,photosynthetic and regulating enzymes,and signaling components that collectively regulate photosynthesis in tomato.Next,we reviewed the advances in tomato photosynthesis,including two aspects of genetic basis and genetic improvement.Numerous genes regulating tomato photosynthesis are gradually uncovered,and the interaction network among those genes remains to be constructed.Finally,the photosynthesis occurring in fruit of tomato and the relationship between photosynthesis in leaf and fruit were discussed.Leaves and fruits are photosynthate sources and sinks of tomato respectively,and interaction between photosynthesis in leaf and fruit exists.Additionally,future perspectives that needs to be addressed on tomato photosynthesis were proposed. 展开更多
关键词 PHOTOSYNTHESIS TOMATO GENETICS improveMENT LEAF FRUIT
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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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Intelligent Factory Vehicle Detection Algorithm Based on Improved YOLOv8 被引量:1
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作者 Qiannian Miao Tianhu Wang Rong Wang 《Instrumentation》 2025年第2期60-70,共11页
Aiming at the problem that the existing algorithms for vehicle detection in smart factories are difficult to detect partial occlusion of vehicles,vulnerable to background interference,lack of global vision,and excessi... Aiming at the problem that the existing algorithms for vehicle detection in smart factories are difficult to detect partial occlusion of vehicles,vulnerable to background interference,lack of global vision,and excessive suppression of real targets,which ultimately cause accuracy degradation.At the same time,to facilitate the subsequent positioning of vehicles in the factory,this paper proposes an improved YOLOv8 algorithm.Firstly,the RFCAConv module is combined to improve the original YOLOv8 backbone.Pay attention to the different features in the receptive field,and give priority to the spatial features of the receptive field to capture more vehicle feature information and solve the problem that the vehicle is partially occluded and difficult to detect.Secondly,the SFE module is added to the neck of v8,which improves the saliency of the target in the reasoning process and reduces the influence of background interference on vehicle detection.Finally,the head of the RT-DETR algorithm is used to replace the head in the original YOLOv8 algorithm,which avoids the excessive suppression of the real target while combining the context information.The experimental results show that compared with the original YOLOv8 algorithm,the detection accuracy of the improved YOLOv8 algorithm is improved by 4.6%on the self-made smart factory data set,and the detection speed also meets the real-time requirements of smart factory vehicle detection and subsequent vehicle positioning. 展开更多
关键词 smart factory vehicle detection improved YOLOv8 vehicle positioning
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Weld defects detection method based on improved YOLOv5s 被引量:1
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作者 Runchao Liu Jiyang Qi +1 位作者 Dongliang Shui Tang Ebolo Micheline Hortense 《China Welding》 2025年第2期119-131,共13页
To solve the problem of low detection accuracy for complex weld defects,the paper proposes a weld defects detection method based on improved YOLOv5s.To enhance the ability to focus on key information in feature maps,t... To solve the problem of low detection accuracy for complex weld defects,the paper proposes a weld defects detection method based on improved YOLOv5s.To enhance the ability to focus on key information in feature maps,the scSE attention mechanism is intro-duced into the backbone network of YOLOv5s.A Fusion-Block module and additional layers are added to the neck network of YOLOv5s to improve the effect of feature fusion,which is to meet the needs of complex object detection.To reduce the computation-al complexity of the model,the C3Ghost module is used to replace the CSP2_1 module in the neck network of YOLOv5s.The scSE-ASFF module is constructed and inserted between the neck network and the prediction end,which is to realize the fusion of features between the different layers.To address the issue of imbalanced sample quality in the dataset and improve the regression speed and accuracy of the loss function,the CIoU loss function in the YOLOv5s model is replaced with the Focal-EIoU loss function.Finally,ex-periments are conducted based on the collected weld defect dataset to verify the feasibility of the improved YOLOv5s for weld defects detection.The experimental results show that the precision and mAP of the improved YOLOv5s in detecting complex weld defects are as high as 83.4%and 76.1%,respectively,which are 2.5%and 7.6%higher than the traditional YOLOv5s model.The proposed weld defects detection method based on the improved YOLOv5s in this paper can effectively solve the problem of low weld defects detection accuracy. 展开更多
关键词 Weld defects detection improved YOLOv5s scSE-ASFF Feature fusion
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