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农户分化对耕地碳生产率的影响研究——以常德市为例

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湖南师范大学自然科学学报 2024年第2期47卷 29-37页

作者：张凤张馨瑶文高辉湖南师范大学地理科学学院长沙410081

在社会经济高速发展、追求绿色低碳农业的背景下,提高耕地碳生产率是实现社会经济可持续发展的有效的途径。研究基于2020年湖南省常德市农户调研数据,运用Tobit模型实证检验了农户分化对耕地碳生产率的影响。研究结果表明:在表征农民分... 详细信息

在社会经济高速发展、追求绿色低碳农业的背景下,提高耕地碳生产率是实现社会经济可持续发展的有效的途径。研究基于2020年湖南省常德市农户调研数据,运用Tobit模型实证检验了农户分化对耕地碳生产率的影响。研究结果表明:在表征农民分化特征的两个变量中,农户职业分化程度对耕地碳生产率有显著的负向影响,且收入分化强化了职业分化对偏非农型农户耕地碳生产率的负向影响效应;收入分化对耕地碳生产率的影响效应受到农户职业分化程度的制约,收入分化对偏农型农户耕地碳生产率有正向影响,职业分化强化了收入分化对偏农型农户耕地碳生产率的正向影响效应;职业分化削弱了收入分化对偏非农型农户耕地碳生产率的影响效应;此外,在其他控制变量中,受教育程度和集镇距离对耕地碳生产率也存在显著的正向影响。

关键词：农户分化耕地碳生产率碳排放 Tobit模型交互效应

Fine-Grained Ship Recognition Based on Visible and Near-Infrared Multimodal Remote Sensing Images: Dataset,Methodology and Evaluation

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Computers, Materials & Continua 2024年第6期79卷 5243-5271页

作者： Shiwen Song Rui zhang Min Hu Feiyao Huang Department of Aerospace Science and Technology Space Engineering UniversityBeijing101416China

Fine-grained recognition of ships based on remote sensing images is crucial to safeguarding maritime rights and interests and maintaining national ***,with the emergence of massive high-resolution multi-modality images,the use of multi-modality images for fine-grained recognition has become a promising ***-grained recognition of multi-modality images imposes higher requirements on the dataset *** key to the problem is how to extract and fuse the complementary features of multi-modality images to obtain more discriminative fusion *** attention mechanism helps the model to pinpoint the key information in the image,resulting in a significant improvement in the model’s *** this paper,a dataset for fine-grained recognition of ships based on visible and near-infrared multi-modality remote sensing images has been proposed first,named Dataset for Multimodal Fine-grained Recognition of Ships(DMFGRS).It includes 1,635 pairs of visible and near-infrared remote sensing images divided into 20 categories,collated from digital orthophotos model provided by commercial remote sensing *** provides two types of annotation format files,as well as segmentation mask images corresponding to the ship ***,a Multimodal Information Cross-Enhancement Network(MICE-Net)fusing features of visible and near-infrared remote sensing images,has been *** the network,a dual-branch feature extraction and fusion module has been designed to obtain more expressive *** Feature Cross Enhancement Module(FCEM)achieves the fusion enhancement of the two modal features by making the channel attention and spatial attention work cross-functionally on the feature map.A benchmark is established by evaluating state-of-the-art object recognition algorithms on ***-Net conducted experiments on DMFGRS,and the precision,recall,mAP0.5 and mAP0.5:0.95 reached 87%,77.1%,83.8%and 63.9%,*** experiments demons

关键词： Multi-modality dataset ship recognition fine-grained recognition attention mechanism

Proof of Aerobically Autoxidized Self-Charge Concept Based on Single Catechol-Enriched Carbon Cathode Material

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Nano-Micro Letters 2024年第4期16卷 1-13页

作者： Junyan Wang Wanchun Guo Kesong Tian xinta Li xinyu Wang Panhua Li Yu zhang Bosen zhang Biao zhang Shuhu Liu Xueai Li Zhaopeng Xu Junjie Xu Haiyan Wang Yanglong Hou State Key Laboratory of Metastable Materials Science and Technology Hebei Key Laboratory of Heavy Metal Deep‑Remediation in Water and Resource ReuseSchool of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao 066004People’s Republic of China Beijing Key Laboratory for Magnetoelectric Materials and Devices Beijing Innovation Centre for Engineering Science and Advanced TechnologySchool of Materials Science and EngineeringPeking UniversityBeijing 100871People’s Republic of China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049People’s Republic of China Xi’an Rare Metal Materials Institute Co.Ltd Xi’an 710016People’s Republic of China

The self-charging concept has drawn considerable attention due to its excellent ability to achieve environmental energy harvesting,conversion and storage without an external power ***,most self-charging designs assembled by multiple energy harvesting,conversion and storage materials increase the energy transfer loss;the environmental energy supply is generally limited by climate and meteorological conditions,hindering the potential application of these selfpowered devices to be available at all *** on aerobic autoxidation of catechol,which is similar to the electrochemical oxidation of the catechol groups on the carbon materials under an electrical charge,we proposed an air-breathing chemical self-charge concept based on the aerobic autoxidation of catechol groups on oxygen-enriched carbon materials to ortho-quinone *** harvesting,conversion and storage functions could be integrated on a single carbon material to avoid the energy transfer loss among the different ***,the assembled Cu/oxygen-enriched carbon battery confirmed the feasibility of the air-oxidation self-charging/electrical discharging mechanism for potential *** air-breathing chemical self-charge concept could facilitate the exploration of high-efficiency sustainable air self-charging devices.

关键词： Carbon material Oxygen functionality Air oxidation self-charge

Cell Consistency Evaluation Method Based on Multiple Unsupervised Learning Algorithms

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Big Data Mining and Analytics 2024年第1期7卷 42-54页

作者： Jiang Chang Xianglong Gu Jieyun Wu Debu zhang Stellantis China Technology Center Shanghai 200233China

Unsupervised learning algorithms can effectively solve sample *** address battery consistency anomalies in new energy vehicles,we adopt a variety of unsupervised learning algorithms to evaluate and predict the battery consistency of three vehicles using charging fragment data from actual operating *** extract battery-related features,such as the mean of maximum difference,standard deviation,and entropy of batteries and then apply principal component analysis to reduce the dimensionality and record the amount of preserved *** then build models through a collection of unsupervised learning algorithms for the anomaly detection of cell consistency *** also determine whether unsupervised and supervised learning algorithms can address the battery consistency problem and document the parameter tuning *** addition,we compare the prediction effectiveness of charging and discharging features modeled individually and in combination,determine the choice of charging and discharging features to be modeled in combination,and visualize the multidimensional data for fault *** results show that the unsupervised learning algorithm is effective in visualizing and predicting vehicle core conformance faults,and can accurately predict faults in real ***“distance+boxplot”algorithm shows the best performance with a prediction accuracy of 80%,a recall rate of 100%,and an F1 of *** proposed approach can be applied to monitor battery consistency faults in real time and reduce the possibility of disasters arising from consistency faults.

关键词： battery consistency charging segment data unsupervised learning

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复杂背景条件下的电气设备图像实例分割算法

电子测量技术 2024年第1期47卷 110-117页

作者：张志君张惊雷贾鑫天津理工大学电气工程与自动化学院天津300384 天津市复杂系统控制理论及应用重点实验室天津300384 天津理工大学工程训练中心天津300384

变电站巡检拍摄的电气设备可见光图像存在背景杂乱、目标轮廓不规则等特点,造成设备分割精度不高,影响智能巡检系统设备识别效果。基于此,提出一种改进的YOLACT++模型,实现设备目标精确实例分割。首先,设计了电气设备特征提取主干网络DA... 详细信息

变电站巡检拍摄的电气设备可见光图像存在背景杂乱、目标轮廓不规则等特点,造成设备分割精度不高,影响智能巡检系统设备识别效果。基于此,提出一种改进的YOLACT++模型,实现设备目标精确实例分割。首先,设计了电气设备特征提取主干网络DAGNet,提升了网络对复杂背景下重要特征的关注度;同时在原型网络分支引入3D注意力模块SimAM,降低混乱背景对目标分割的干扰。使用某市8个区域58座110 kV变电站和86座35 kV变电站巡检所得避雷器、断路器等6类电气设备的1730张可见光图像的标记数据集对该模型进行验证,实验结果表明,改进YOLACT++模型分割的AP_(all)指标为84.1%,相较原模型提高了4.4%,与YOLACT、Mask R-CNN和YOLOv8模型相比分别高出4.0%、9.3%、1.6%,较好地实现了6类电气设备的识别,可满足电力巡检中准确性和快速性的要求。

关键词：电气设备识别实例分割 YOLACT++ 可见光图像

Repositioning fertilizer manufacturing subsidies for improving food security and reducing greenhouse gas emissions in China

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Journal of Integrative Agriculture 2024年第2期23卷 430-443页

作者： Zongyi Wu Xiaolong Feng Yumei zhang Shenggen Fan Academy of Global Food Economics and Policy China Agricultural UniversityBeijing 100083China College of Economics and Management China Agricultural UniversityBeijing 100083China

China removed fertilizer manufacturing subsidies from 2015 to 2018 to bolster market-oriented reforms and foster environmentally sustainable ***,the impact of this policy reform on food security and the environment remains inadequately ***,although green and low-carbon technologies offer environmental advantages,their widespread adoption is hindered by prohibitively high *** study analyzes the impact of removing fertilizer manufacturing subsidies and explores the potential feasibility of redirecting fertilizer manufacturing subsidies to invest in the diffusion of these *** the China Agricultural University Agri-food Systems model,we analyzed the potential for achieving mutually beneficial outcomes regarding food security and environmental *** findings indicate that removing fertilizer manufacturing subsidies has reduced greenhouse gas(GHG)emissions from agricultural activities by 3.88 million metric tons,with minimal impact on food *** fertilizer manufacturing subsidies to invest in green and low-carbon technologies,including slow and controlled-release fertilizer,organic-inorganic compound fertilizers,and machine deep placement of fertilizer,emerges as a strategy to concurrently curtail GHG emissions,ensure food security,and secure robust economic ***,we propose a comprehensive set of government interventions,including subsidies,field guidance,and improved extension systems,to promote the widespread adoption of these technologies.

关键词： food security fertilizer manufacturing subsidies agri-food systems greenhouse gas emissions

Distributed Dynamic Load in Structural Dynamics by the Impulse-Based Force Estimation Algorithm

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2865-2891页

作者： Yuantian Qin Yucheng zhang Vadim V.Silberschmidt College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing210016China Wolfson School of Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughboroughLE113TUUK

This paper proposes a novel approach for identifying distributed dynamic loads in the time *** polynomial andmodal analysis,the load is transformed intomodal space for coefficient *** allows the distributed dynamic load with a two-dimensional form in terms of time and space to be simultaneously identified in the form of modal force,thereby achieving dimensionality *** Impulse-based Force Estimation Algorithm is proposed to identify dynamic loads in the time ***,the algorithm establishes a recursion scheme based on convolution integral,enabling it to identify loads with a long history and rapidly changing forms over ***,the algorithm introduces moving mean and polynomial fitting to detrend,enhancing its applicability in load *** aforementioned methodology successfully accomplishes the reconstruction of distributed,instead of centralized,dynamic loads on the continuum in the time domain by utilizing acceleration *** validate the effectiveness of the method,computational and experimental verification were conducted.

关键词： Distributed force estimation time domain deconvolution recursion

Total Synthesis of Laurane and Guaiane Sesquiterpenoids via Oxidative Nazarov Reaction

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Chinese Journal of Chemistry 2024年第11期42卷 1267-1274页

作者： Yuye Chen Wenqing Chen Zhiting zhang Jing Xu Shenzhen Grubbs Institute and Department of Chemistry and Guangming Advanced Research Institute and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis Southern University of Science and TechnologyShenzhenGuangdong518055 China

As one of the most common structural motifs in natural products,cyclopentenones usually can be fabricated by Nazarov cyclization using divinyl ketones or functionalized tertiary divinyl carbinols(TDCs)as ***,straightforward method for transforming unfunctionalized TDCs to their corresponding cyclopentenones is currently ***,we wish to report the total syntheses of four structurally distinct terpenoids,namely laurane-type marine sesquiterpenoids isolaurene,debromoaplysin and aplysin,and guaiane sesquiterpenoid guaiadienone A,all using a novel synthetic method,named oxidative Nazarov cyclization,as the key *** work demonstrated our robust method is suitable for synthesizing various highly substituted cyclopentenones.

关键词： Total synthesis Synthetic methods Sesquiterpenoids Oxidative Nazarov reaction Electrocyclization Oxoammonium salt Pericyclic reaction Annulation

IN783低膨胀高温合金的热变形行为和组织演变

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稀有金属材料与工程 2024年第7期53卷 2006-2017页

作者：苏海王晨罗通黄海亮张华张尚洲江亮周鑫烟台大学精准材料高等研究院山东烟台264005 贵州安大航空锻造有限责任公司贵州安顺561005

通过热压缩试验研究了IN783低膨胀高温合金在温度为1000~1120℃、应变速率为0.01~10 s^(-1)条件下的热变形行为,并采用电子背散射衍射(EBSD)研究了不同变形参数下合金的组织演变规律。结果表明,IN783合金的流变应力随着温度的升高和应... 详细信息

通过热压缩试验研究了IN783低膨胀高温合金在温度为1000~1120℃、应变速率为0.01~10 s^(-1)条件下的热变形行为,并采用电子背散射衍射(EBSD)研究了不同变形参数下合金的组织演变规律。结果表明,IN783合金的流变应力随着温度的升高和应变速率的减小而显著降低。基于Arrhenius方程和Zener-Hollomon参数模型,建立了该合金的本构方程为:ε=3.58237×10^(15)[sinh(0.00495724σ)]^(3.99121)exp(-417.146551/RT),可以很好地描述热变形过程中流变应力与变形温度和应变速率的关系。基于动态材料模型绘制了IN783合金的热加工图,并根据热加工图和微观组织分析,确定IN783镍基高温合金热加工的安全区间为:1000~1080℃/0.1~10 s^(-1),以及1000~1040℃/0.01~0.1 s^(-1)。此外,在高温低速率条件下(1060~1120℃、0.01 s^(-1)),尽管合金具有较高的功率耗散值,但会出现混晶组织和晶粒粗化现象,也不适合作为IN783合金的热加工区间。

关键词： IN783高温合金热变形行为热加工图组织演变