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Bearing capacity,shear band evolution,and deformation characteristics of slopes reinforced by root-inspired anchors using transparent soil model testing
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作者 Ruijie Huang Wengang Zhang +6 位作者 Jiaying Xiang Ningning Zhang Matteo Oryem Ciantia Jian Yin Leilei Liu Jushan Wang Anzhai Fei 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期457-471,共15页
Root-inspired anchorage systems in the field of bio-inspired geotechnics are renowned for enhancing the pullout capacity of traditional geotechnical anchorage systems by simulating the morphology and architecture of p... Root-inspired anchorage systems in the field of bio-inspired geotechnics are renowned for enhancing the pullout capacity of traditional geotechnical anchorage systems by simulating the morphology and architecture of plant root systems.However,limited studies have explored their practical applications,particularly in improving slope stability.To fill this gap,this study investigates the reinforcement effect of root-inspired anchors on slope stabilization using transparent soil modeling and 3D-printed anchors,and examines the impact of anchor branching patterns(i.e.branching numbers,branching angle,and branching nodes)on slope bearing capacity,shear band evolution,and temporal and spatial variation of slope deformation.The results show that peak slope bearing capacity increases with branching numbers and branching angles,correlating with the envelope area of the curved shear band.Upper anchors result in step-like deflections in the shear band near the trailing edge,while lower anchors convert the upward concave shear band into an upward convex one,thus increasing the slope bearing capacity.Slope deformation is minimized with intermediate branching parameters,such as a branching number of 4 and a branching angle of 45°.The anchor reinforcement mechanisms,i.e.anchor rod shear resistance,interface friction,anchor pullout capacity,and plate tightening effects,are comprehensively discussed,and the installation effects resulting from compromise slope modeling are identified as the contributors.These findings shed light on the failure process of root-inspired anchors reinforced slopes and provide a preliminary reference for potential applications,especially for the tradeoff between anchor branching,slope deformation,and slope stability. 展开更多
关键词 Bio-inspired geotechnics Root-inspired anchors Transparent cemented soil Slope bearing capacity Shear band evolution
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农户耕地轮作决策的前因条件与组态路径 被引量:1
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作者 杜国明 李升生 卢汇川 《东北农业大学学报(社会科学版)》 2025年第2期64-73,共10页
为推动农户落实耕地轮作政策、健全我国耕地轮作制度,文章运用模糊集定性比较分析(fsQCA)方法,深入探讨了农户在耕地轮作决策中的前因条件及组态路径。研究表明,农户轮作行为受多因素叠加形成的复合效应影响,主要可归纳为三种路径类型,... 为推动农户落实耕地轮作政策、健全我国耕地轮作制度,文章运用模糊集定性比较分析(fsQCA)方法,深入探讨了农户在耕地轮作决策中的前因条件及组态路径。研究表明,农户轮作行为受多因素叠加形成的复合效应影响,主要可归纳为三种路径类型,即“耕地资源+思想认识驱动型”“人力资源+思想认识驱动型”以及“双重资源+技能提升引领型”。上述路径与农户生计特征密切相关,不同类型农户在轮作路径选择上差异显著。此外,对轮作政策的理解、生态保护意识以及技术培训是增强轮作采纳意愿的关键激励因素。基于此,提出分层协同策略:针对家庭农场和种粮大户通过智能设备与服务补贴以及合理规划提升轮作效率;针对小农户通过土地流转与社会化服务降低轮作参与门槛;针对农业生产合作社选拔骨干参与人才培训发挥示范作用。同时,需完善政策支撑体系,差异化配置补贴、信贷与基础设施资源,深化政策宣导的靶向性与实操性,最终形成农业生产提质、农户增收与耕地可持续利用的共赢格局。 展开更多
关键词 耕地保护 耕地轮作 模糊集定性比较分析 组态路径
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中国茶产业对区域经济发展贡献研究 被引量:7
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作者 李梓萌 张婉洁 《云南农业大学学报(社会科学版)》 2025年第1期45-53,共9页
本研究全面评估中国茶产业的现状及其对区域经济的多维贡献。采用定性与定量相结合的混合研究方法,分析茶产业对区域经济的直接(如GDP、税收、农民收入)与间接(如旅游促进、文化传承)贡献。研究发现,中国茶产业规模不断扩大,区域分布广... 本研究全面评估中国茶产业的现状及其对区域经济的多维贡献。采用定性与定量相结合的混合研究方法,分析茶产业对区域经济的直接(如GDP、税收、农民收入)与间接(如旅游促进、文化传承)贡献。研究发现,中国茶产业规模不断扩大,区域分布广泛,贸易活跃,市场消费趋势多元化。茶产业不仅显著促进了地方GDP增长、增加了政府税收、提高了农民收入,还在促进就业、文化保护、生态环境保护等方面展现了非经济但至关重要的价值。然而,茶产业也面临市场竞争加剧、自然灾害频发和国际市场不确定性等挑战。为此,本研究提出加强科技创新与品牌建设、完善风险管理与应急机制、深化国际合作等策略,推动茶产业的转型升级与可持续发展。为政策制定、行业实践和学术研究提供有益参考,并有望推动中国茶产业在全球化背景下实现高质量发展,进一步促进区域经济繁荣。 展开更多
关键词 茶产业 区域经济 茶叶贸易
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中国服装制造企业数字化转型路径组态分析
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作者 吕洁 Tianyi Cui 王保鲁 《丝绸》 北大核心 2025年第10期1-11,共11页
作为劳动密集型产业的典型代表,服装制造业急需通过数字化转型提升其国际竞争力。因技术基础、资源禀赋、外部环境差异,服装制造企业数字化转型具有显著的个体差异性与情境复杂性,而现有研究多局限于线性视角,缺乏对转型驱动因素组态效... 作为劳动密集型产业的典型代表,服装制造业急需通过数字化转型提升其国际竞争力。因技术基础、资源禀赋、外部环境差异,服装制造企业数字化转型具有显著的个体差异性与情境复杂性,而现有研究多局限于线性视角,缺乏对转型驱动因素组态效应的关注。为此,本文基于技术-组织-环境理论框架,运用模糊集定性比较分析方法,对18家服装制造企业的71组样本数据进行分析,识别企业数字化转型的组态路径。研究发现,服装制造企业存在复合驱动型、策略引领型和技术主导型三种数字化转型路径,揭示了技术能力、组织变革和环境支撑三要素之间的非线性交互作用。研究结果可为企业制定差异化转型策略及政府优化产业政策提供理论依据和实践参考。 展开更多
关键词 数字化转型 服装制造 组态分析 TOE框架 fsQCA 企业转型路径
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Transcriptional profiling during infection of potato NLRs and Phytophthora infestans effectors using cDNA enrichment sequencing 被引量:1
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作者 Amanpreet Kaur Vikrant Singh +6 位作者 Stephen Byrne Miles Armstrong Thomas M.Adams Brian Harrower Eleanor Gilroy Ewen Mullins Ingo Hein 《The Crop Journal》 2025年第1期31-40,共10页
An accurate assessment of host and pathogen gene expression during infection is critical for understanding the molecular aspects of host-pathogen interactions.Often,pathogen-derived transcripts are difficult to ascert... An accurate assessment of host and pathogen gene expression during infection is critical for understanding the molecular aspects of host-pathogen interactions.Often,pathogen-derived transcripts are difficult to ascertain at early infection stages owing to the unfavourable transcript representation compared to the host genes.In this study,we compare two sequencing techniques,RNAseq and enrichment sequencing(RenSeq and PenSeq)of cDNA,to investigate gene expression patterns in the doubled monoploid potato(DM)infected with the late blight pathogen Phytophthora infestans.Our results reveal distinct advantages of cDNA RenSeq and PenSeq over traditional RNAseq in terms of target gene representation and transcriptional quantification at early infection stages.Throughout the infection time course,cDNA enrichment sequencing enables transcriptomic analyses for more targeted host and pathogen genes.For highly expressed genes that were sampled in parallel by both cDNA enrichment and RNAseq,a high level of concordance in expression profiles is observed,indicative of at least semi-quantitative gene expression representation following enrichment. 展开更多
关键词 RxLR effector NLRS Late blight POTATO cDNA sequencing RenSeq PenSeq RNASEQ
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High-Precision and Ultraspeed Monitoring of Melt-Pool Morphology in Laser-Directed Energy Deposition Using Deep Learning 被引量:2
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作者 Jiayu Yang Guan Liu +4 位作者 Wei Zhu Yingjie Zhang Wenbin Zhou Defu Liu Yongcheng Lin 《Additive Manufacturing Frontiers》 2025年第2期81-89,共9页
Laser-directed energy deposition(L-DED)is an advanced additive manufacturing technology primarily adopted in metal three-dimensional printing systems.The L-DED process is characterized by various defects,thus necessit... Laser-directed energy deposition(L-DED)is an advanced additive manufacturing technology primarily adopted in metal three-dimensional printing systems.The L-DED process is characterized by various defects,thus necessitating the extensive use of in-situ monitoring to enable real-time adjustments of process parameters by detecting molten-pool features.To address the challenge of accurately extracting the molten-pool morphology from an undetached spatter,an innovative monitoring method based on the U-Net(U-shaped network)is proposed herein.A lightweight architecture accelerates the processing speed,whereas an enhanced loss function incorporating weight maps augments the segmentation precision.The model performance is evaluated by comparing its segmentation accuracy and processing speed with those of the conventional U-Net,using the mean intersection over union(MIoU)as the segmentation metric.The improved model demonstrates superior segmentation accuracy at the interface between the molten pool and spatter,with a peak MIoU of 0.9798 achieved on the test set.Furthermore,this model processes each image in an extremely short time of 17.9 ms.Using this segmentation algorithm,the error in extracting the molten-pool width from single-track experiments is within 0.1 mm.The proposed method for monitoring the molten-pool morphology is suitable for deployment in online monitoring systems,thus providing a foundation for subsequent process-parameter regulation. 展开更多
关键词 Laser-directed energy deposition Molten-pool morphology Semantic segmentation Mean intersection over union(MIoU)
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近现代高等教育促进我国社会流动的演进分析及启示探讨
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作者 夏思雨 《大学》 2025年第4期55-58,共4页
教育是振兴民族的基石,是培养优质人才的重要渠道。随着我国近代逐渐和西方接轨,先进的社会制度和教育机制开始在国内出现并不断发展。高等教育正是在这一时代背景下得以建立并逐步壮大的教育形式。高等教育的发展对一个国家、一个社会... 教育是振兴民族的基石,是培养优质人才的重要渠道。随着我国近代逐渐和西方接轨,先进的社会制度和教育机制开始在国内出现并不断发展。高等教育正是在这一时代背景下得以建立并逐步壮大的教育形式。高等教育的发展对一个国家、一个社会有着非常重大的影响。这种影响主要表现在两个方面:一方面是固化,高等教育在一定程度上导致社会阶层固化、教育体系规划和就业市场显著提升;另一方面则是延伸和拓展,高等教育实现了知识与技能的传递,构建了丰富的社会网络,同时促进了文化资本的积累。因此,综合高等教育对社会发展的认知,可以明确未来的社会发展中应当进一步维护高等教育公平,加速推进高等教育的去分层化,也要确保高等教育和市场需求协同。 展开更多
关键词 高等教育 近现代 社会流动 去分层化 市场需求
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抖音平台《红楼梦》的大众传播生态与经典重构研究--兼论短视频平台对古代文学传播的启示
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作者 高斯可 《艺术科技》 2025年第10期146-148,共3页
目的:文章旨在探讨抖音平台《红楼梦》的大众传播生态与经典重构,分析短视频平台对古代文学传播的启示。方法:以抖音平台《红楼梦》传播现象为研究对象,结合具体案例分析其传播生态革新,包括传播主体去中心化、接受方式互动化、传播功... 目的:文章旨在探讨抖音平台《红楼梦》的大众传播生态与经典重构,分析短视频平台对古代文学传播的启示。方法:以抖音平台《红楼梦》传播现象为研究对象,结合具体案例分析其传播生态革新,包括传播主体去中心化、接受方式互动化、传播功能媒介化延伸等特征,并探讨传播中的误读错解与娱乐化倾向。选取“米三汉解读《红楼梦》”“甜甜老师讲文学”等典型传播样本,解析其内容生产机制、用户参与模式及社会话题衍生路径;运用文本分析法,对2000多条用户弹幕、评论进行情感倾向与主题聚类,揭示受众认知偏差与娱乐化倾向的深层动因;结合传播学理论,构建“技术赋能—内容重构—文化反馈”三维分析框架,探讨短视频平台对古代文学经典传播范式的颠覆性影响。结果:抖音重塑了《红楼梦》的传播范式,但也带来学术严谨性与大众解读冲突、严肃文学与娱乐化传播博弈等问题。结论:文章提出从传播者、平台、受众三方面协同发力的优化路径,包括强化专业引导、规范传播生态、提升受众素养等,以实现《红楼梦》等古代文学经典在短视频时代的良性传播。研究不仅为《红楼梦》的良性传播提供理论支撑,也为短视频时代古代文学经典的重构与跨媒介传承提供了可复制的实践框架,揭示了技术驱动下文化传播“破圈”与“守正”的动态平衡机制。 展开更多
关键词 抖音 《红楼梦》 大众传播
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高等教育快速发展对社会就业观念的多元影响:机遇、挑战与重构
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作者 夏思雨 《大学》 2025年第2期25-28,共4页
我国高等教育始终迈进在快速发展的道路上,这对社会就业观念产生了多方面的影响。拓宽就业者的就业视野、提升就业竞争力认知是高等教育发展为就业观念带来的机遇。就业期望与现实的落差、职业稳定性的改变、就业市场供需结构失衡和社... 我国高等教育始终迈进在快速发展的道路上,这对社会就业观念产生了多方面的影响。拓宽就业者的就业视野、提升就业竞争力认知是高等教育发展为就业观念带来的机遇。就业期望与现实的落差、职业稳定性的改变、就业市场供需结构失衡和社会分层与就业观念的扭曲是高等教育发展给就业观念带来的挑战。对此,文章从个人层面、高校教育层面、社会层面提出重构建议。 展开更多
关键词 高等教育扩张 社会就业观念 机遇和挑战 就业观念重构
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中韩高校国际学生趋同化管理对我国来华留学教育管理的启示
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作者 夏欣欣 程子墨 《现代商贸工业》 2025年第4期43-45,共3页
近年来,趋同化管理已成为国内外高校培养留学生的主要模式和提高国际学生教学质量的根本措施。随着新时代我国来华留学事业飞速发展,虽已从规模扩张阶段步入全新的提质增效阶段,但我国高校趋同化管理尚处于发展期。本研究发现当前我国... 近年来,趋同化管理已成为国内外高校培养留学生的主要模式和提高国际学生教学质量的根本措施。随着新时代我国来华留学事业飞速发展,虽已从规模扩张阶段步入全新的提质增效阶段,但我国高校趋同化管理尚处于发展期。本研究发现当前我国部分高校对趋同化管理理念、来华留学生教学管理、日常管理服务等方面仍然存在着认识不足、协同不强、支持不够的问题。基于此,本研究从对韩国高校对待国际学生的管理模式入手,结合国内外学生管理特色经验,从中提炼出我国高校来华留学趋同化管理的提升对策,旨在实现来华留学教育管理与我国教育体系的有机融合。 展开更多
关键词 中韩高校 趋同化管理 来华留学 教育管理
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Coin impact on cross‑crypto realized volatility and dynamic cryptocurrency volatility connectedness
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作者 Burak Korkusuz Mehmet Sahiner 《Financial Innovation》 2025年第1期3732-3763,共32页
This study evaluates the predictive accuracy of traditional time series(TS)models versus machine learning(ML)methods in forecasting realized volatility across major cryptocurrencies—Bitcoin(BTC),Ethereum(ETH),Litecoi... This study evaluates the predictive accuracy of traditional time series(TS)models versus machine learning(ML)methods in forecasting realized volatility across major cryptocurrencies—Bitcoin(BTC),Ethereum(ETH),Litecoin(LTC),and Ripple(XRP).Employing high-frequency data,we analyze cross-cryptocurrency volatility dynamics through two complementary approaches:volatility forecasting and connectedness analysis.Our findings reveal three key insights:(i)TS models,particularly the heterogeneous autoregressive(HAR)model,exhibit superior predictive performance over their ML counterparts,with the long short-term memory(LSTM)model providing competitive yet inconsistent results due to overfitting and short-term volatility challenges;(ii)including lagged realized volatility of large-cap coins improves predictive accuracy for mid-cap coins,especially XRP,whereas forecasts for largecap coins remain stable,indicating more resilient volatility patterns;and(iii)volatility connectedness analysis reveals substantial spillover effects,particularly pronounced during market turmoil,with large-cap assets(BTC and ETH)acting as primary volatility transmitters and mid-cap assets(XRP and LTC)serving as volatility receivers.These results contribute to the understanding of volatility forecasting and risk management in cryptocurrency markets,offering implications for investors and policymakers in managing market risk and interdependencies in digital asset portfolios. 展开更多
关键词 Volatility forecasting Realized volatility Bitcoin Cross-cryptocurrency impact Dynamic connectedness Machine learning Network analysis Econometric models
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Evaluation of soil metazoan communities under short-term elevated CO_(2)and O_(3)concentrations in a paddy soil
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作者 Jianqing WANG Jiaoyan MAO +5 位作者 Manuel Esteban LUCAS-BORJA Yunyan TAN Yajun SHAO Roy NEILSON Xiuzhen SHI Guoyou ZHANG 《Pedosphere》 2025年第3期560-568,共9页
Soil biota mediates key ecological processes and delivers a range of societally important ecosystem services.However,the impacts of atmospheric changes on soil metazoans have been understudied.To address this knowledg... Soil biota mediates key ecological processes and delivers a range of societally important ecosystem services.However,the impacts of atmospheric changes on soil metazoans have been understudied.To address this knowledge gap,we evaluated the short-term responses of soil metazoans to elevated carbon dioxide(CO_(2))and ozone(O_(3))with two commonly grown rice varieties(Nanjing 5055 and Wuyujing 3)in a paddy soil.A simultaneous increase of CO_(2)and O_(3)concentrations had a negligible effect on the diversity of Annelida,Mollusca,Porifera,and total soil metazoans,suggesting that soil metazoan taxa had an inherent resilience to atmospheric changes.However,elevated CO_(2)alone significantly enhanced the diversity and relative abundances of Craniata and Platyhelminthes for Wuyujing 3 under ambient O_(3)conditions.However,elevated O_(3)decreased the diversity and relative abundance of Craniata by 42.7%and 47.7%,respectively,especially under elevated CO_(2)conditions for Wuyujing 3,demonstrating significant interactive effects.Furthermore,soil NO_(3)^(-)-N and NH_(4)^(+)-N contents mostly shaped the changes in the diversity and composition of soil metazoan communities.These results highlight the crucial role of rice variety regulating soil metazoan communities under the complex interaction between short-term elevated CO_(2)and O3.Thus,to better understand the mechanisms and processes within soil food webs,future studies should include the combined effects of various climate change factors and different crop varieties on soil metazoan communities. 展开更多
关键词 climate change CO_(2)enrichment enhanced ozone environmental DNA rice varieties soil fauna soil food web
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Role of root morphological and architectural traits:Insights into root-inspired anchorage and updates foundation systems
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作者 Wengang Zhang Ruije Huang +5 位作者 Jiaying Xiang Ningning Zhang Matteo Oryem Ciantia Leilei Liu Jian Yin Changbing Qin 《Biogeotechnics》 2025年第1期72-74,共3页
Plant root systems,a crucial component of biogeotechnics,have been recognized as a promising and sustainable strategy to address novel challenges in geotechnical engineering,i.e.,climate change(Ng et al.,2022).Root-so... Plant root systems,a crucial component of biogeotechnics,have been recognized as a promising and sustainable strategy to address novel challenges in geotechnical engineering,i.e.,climate change(Ng et al.,2022).Root-soil composite and root-reinforced slopes have re-ceived widespread attention in recent decades,due to the ability of root to regulate soil properties through mechanical reinforcement and hy-draulic transpiration(Li&Duan,2023;Ni et al.,2024).Fig.1 provides a co-occurrence network plot of plant root-based soil reinforcement strategies published over the last decade,where three clusters are identified with different colors.On the left of the network map,clusters in red and blue are primarily driven by geotechnical investigations of vegetated slopes(i.e.,plant root reinforced slopes)and root-soil com-posite/root-permeated soils,as denoted by the terms like"model","test","slope","strength"and"vegetation",while the green cluster on the right side demonstrates botany-related domains,for instance,"plant growth",Indeed,the reinforcement of vegetated soil strength is com-plex and varies significantly with an abundance of factors,both me-chanically and hydraulically.Particularly,the impact of root mor-phology and architecture cannot be negligible,including keywords"root area ratio"root distribution""root morphology"root diame-ter"root density"in Fig.1 with the root size and root depth ranking foremost. 展开更多
关键词 root architecture regulate soil properties root morphology plant root systemsa root soil composite plant root geotechnical engineeringieclimate change ng mechanical reinforcement
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Reconstruction of pile-up events using a one-dimensional convolutional autoencoder for the NEDA detector array
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作者 J.M.Deltoro G.Jaworski +15 位作者 A.Goasduff V.González A.Gadea M.Palacz J.J.Valiente-Dobón J.Nyberg S.Casans A.E.Navarro-Antón E.Sanchis G.de Angelis A.Boujrad S.Coudert T.Dupasquier S.Ertürk O.Stezowski R.Wadsworth 《Nuclear Science and Techniques》 2025年第2期62-70,共9页
Pulse pile-up is a problem in nuclear spectroscopy and nuclear reaction studies that occurs when two pulses overlap and distort each other,degrading the quality of energy and timing information.Different methods have ... Pulse pile-up is a problem in nuclear spectroscopy and nuclear reaction studies that occurs when two pulses overlap and distort each other,degrading the quality of energy and timing information.Different methods have been used for pile-up rejection,both digital and analogue,but some pile-up events may contain pulses of interest and need to be reconstructed.The paper proposes a new method for reconstructing pile-up events acquired with a neutron detector array(NEDA)using an one-dimensional convolutional autoencoder(1D-CAE).The datasets for training and testing the 1D-CAE are created from data acquired from the NEDA.The new pile-up signal reconstruction method is evaluated from the point of view of how similar the reconstructed signals are to the original ones.Furthermore,it is analysed considering the result of the neutron-gamma discrimination based on charge comparison,comparing the result obtained from original and reconstructed signals. 展开更多
关键词 1D-CAE Autoencoder CAE Convolutional neural network(CNN) Neutron detector Neutron-gamma discrimination(NGD) Machine learning Pulse shape discrimination Pile-up pulse
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Cost and benefit analysis of Climate-Smart Agriculture interventions in the dryland farming systems of northern Ghana
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作者 Felix KPENEKUU Philip ANTWI-AGYEI +7 位作者 Fred NIMOH Andrew DOUGILL Albert BANUNLE Jonathan ATTA-AIDOO Frank BAFFOUR-ATA Thomas Peprah AGYEKUM Godfred ADDAI Lawrence GUODAAR 《Regional Sustainability》 2025年第1期49-62,共14页
There is a need for more focus in understanding the economic benefits of Climate-Smart Agriculture(CSA)interventions,particularly in sub-Saharan Africa,where extreme climate events are significantly affecting agricult... There is a need for more focus in understanding the economic benefits of Climate-Smart Agriculture(CSA)interventions,particularly in sub-Saharan Africa,where extreme climate events are significantly affecting agriculture and rural livelihoods.This study used the Net Present Value(NPV),Internal Rate of Return(IRR),Benefit-Cost Ratio(BCR),and payback period to evaluate the economic viability of the adopted CSA interventions in the three villages(Doggoh,Jeffiri,and Wulling)of the dryland farming systems of northern Ghana,where CSA interventions were mostly practiced.Data were collected from 161 farm households by the questionnaire survey.The results showed that CSA interventions including livestock-crop integration,mixed cropping,crop rotation,nutrient integration,and tie ridging enhanced crop yield and the household income of smallholder farmers.The five CSA interventions selected by smallholders were in the following order of priority:livestock-crop integration(BCR=2.87),mixed cropping(BCR=2.54),crop rotation(BCR=2.24),nutrient integration(BCR=1.98),and tie ridging(BCR=1.42).Results further showed that livestock-crop integration was the most profitable CSA intervention even under a pessimistic assumption with a long payback period of 5.00 a.Moreover,this study indicated that the implementation of CSA interventions,on average,was relatively profitable and had a nominal financial risk for smallholder farmers.Understanding the economic viability of CSA interventions will help in decision-making process toward selecting the right CSA interventions for resilience development. 展开更多
关键词 Climate-Smart Agriculture(CSA) Economic viability Internal Rate of Return(IRR) Benefit-Cost Ratio(BCR) Payback period Climate change
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Zeeman splitting observations in laser-produced magnetized blast waves
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作者 A.Triantafyllidis J.-R.Marquès +10 位作者 S.Ferri A.Calisti Y.Benkadoum Y.De León A.Dearling A.Ciardi J.Béard J.-M.Lagarrigue N.Ozaki M.Koenig B.Albertazzi 《Matter and Radiation at Extremes》 2025年第4期70-79,共10页
We report the observation of Zeeman splitting in multiple spectral lines emitted by a laser-produced,magnetized plasma(1–3×10^(18)cm^(-3),1–15 eV)in the context of a laboratory astrophysics experiment under a c... We report the observation of Zeeman splitting in multiple spectral lines emitted by a laser-produced,magnetized plasma(1–3×10^(18)cm^(-3),1–15 eV)in the context of a laboratory astrophysics experiment under a controlled magneticfield up to 20T.Nitrogen lines(NII)in the visible range were used to diagnose the magneticfield and plasma conditions.This was performed by coupling our data with(563–574 nm)the Stark–Zeeman line-shape code PPPB.The excellent agreement between experiment and simulations paves the way for a non-intrusive experimental platform to get time-resolved measurements of the local magneticfield in laboratory plasmas. 展开更多
关键词 laboratory astrophysics experiment zeeman splitting diagnose magnetic eld plasma conditionsthis Zeeman splitting controlled magnetic eld nitrogen lines coupling our data laser produced magnetized plasma
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模拟库水位变化的抗滑桩加固边坡离心模型试验研究 被引量:17
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作者 李邵军 KNAPPETT J A +1 位作者 冯夏庭 陈静 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2009年第5期939-946,共8页
抗滑桩是边坡深层抗滑最为有效的措施之一,以三峡库区边坡抗滑桩加固工程为背景,利用离心模型试验手段,模拟库区蓄水和水位循环变化条件下失稳边坡的抗滑桩加固机制。详细介绍相应的离心模型试验方法,通过对一系列自然边坡和不同桩间距... 抗滑桩是边坡深层抗滑最为有效的措施之一,以三峡库区边坡抗滑桩加固工程为背景,利用离心模型试验手段,模拟库区蓄水和水位循环变化条件下失稳边坡的抗滑桩加固机制。详细介绍相应的离心模型试验方法,通过对一系列自然边坡和不同桩间距条件下的模型试验,获得库水位变化影响下的边坡变形、破坏模式和抗滑桩受力,探讨滑坡推力的分布以及不同桩间距条件下的抗滑桩-边坡相互作用机制。测试结果表明,受抗滑桩加固的边坡在水位升降作用下仍发生一定程度的变形并产生裂缝,随着抗滑桩的直接支挡和桩后土体由于不均匀位移产生土拱效应后,边坡变形逐渐得到较好的控制。在本试验条件下,随着桩间距的增大,边坡变形总体上表现为增大趋势,但抗滑桩的受力呈现出先增大后减小的抛物线型变化形态,在某一最适桩间距情况下抗滑桩的抗滑性能得到了最充分的发挥,而滑坡推力表现出复合三角形分布特征。该研究结果为桩土相互作用和库区边坡抗滑桩加固机制分析提供了直接的试验依据,对丰富抗滑桩设计理论和库区边坡的防灾减灾研究具有较为重要的意义。 展开更多
关键词 边坡工程 库区边坡 库水位变化 抗滑桩加固 离心模型试验 最适桩间距
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钢筋混凝土结构锈蚀损伤的解析解 被引量:53
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作者 郑建军 周欣竹 LI Chun-qing 《水利学报》 EI CSCD 北大核心 2004年第12期62-68,共7页
分析了钢筋混凝土结构由于钢筋锈蚀所引发的损伤全过程。假设钢筋周围铁锈层厚相等并考虑混凝土的软化特性,提出了混凝土保护层锈蚀损伤模型,该模型将混凝土保护层的损伤全过程分为弹性变形和部分开裂两个阶段,通过建立和求解各阶段的... 分析了钢筋混凝土结构由于钢筋锈蚀所引发的损伤全过程。假设钢筋周围铁锈层厚相等并考虑混凝土的软化特性,提出了混凝土保护层锈蚀损伤模型,该模型将混凝土保护层的损伤全过程分为弹性变形和部分开裂两个阶段,通过建立和求解各阶段的微分方程,给出了每一时刻混凝土保护层中各点的位移和应力。基于这些解析解,获得了初裂时间、完全开裂时间和每一时刻的锈胀力。对不同的保护层厚度和锈蚀率将本文解析解与实验结果进行了比较,从而证实了本文解的有效性。最后,对计算结果进行了详细的讨论。 展开更多
关键词 混凝土 锈蚀损伤 初裂 完全开裂 锈胀力
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水锤诱发弱约束管道流固耦合振动频谱分析 被引量:16
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作者 张立翔 黄文虎 A.S.Tijsseling 《工程力学》 EI CSCD 北大核心 2000年第1期1-12,共12页
本文在充分利用现有MOC法优点的基础上,提出一种与其十分相似的频谱分析法。该方法能解析分析水锤诱发作用下输流管道流固耦合振动的频谱特性,并能直接考虑色散和能量耗散对系统运动的影响。使用该方法能在任意激源和各种边界条件... 本文在充分利用现有MOC法优点的基础上,提出一种与其十分相似的频谱分析法。该方法能解析分析水锤诱发作用下输流管道流固耦合振动的频谱特性,并能直接考虑色散和能量耗散对系统运动的影响。使用该方法能在任意激源和各种边界条件下得到管道频谱和色散曲线。文中以英国丹迪大学流体力学实验室的标准试验装置为例,说明了该方法的应用。 展开更多
关键词 频谱分析 水锤 管道 流固耦合 振动
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土壤食细菌线虫的原位富集培养方法 被引量:6
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作者 毛小芳 胡锋 +2 位作者 陈小云 Griffiths Bryan 李辉信 《生态学报》 CAS CSCD 北大核心 2007年第2期650-654,共5页
采用两种孔径的尼龙网袋(1mm和5μm),将盆钵供试土壤分成内外两层,内层土壤混合猪粪或稻草,并以不添加猪粪和稻草的供试土壤作为空白;外层直接接入供试土壤,进行培养,以获取土著食细菌线虫大量富集的试验土壤。结果表明:添加基质(猪粪... 采用两种孔径的尼龙网袋(1mm和5μm),将盆钵供试土壤分成内外两层,内层土壤混合猪粪或稻草,并以不添加猪粪和稻草的供试土壤作为空白;外层直接接入供试土壤,进行培养,以获取土著食细菌线虫大量富集的试验土壤。结果表明:添加基质(猪粪和稻草)显著地促进了土壤线虫的繁殖,大量繁殖的线虫通过1mm网袋迁移至外层未加基质的土壤,而采用5μm网袋则限制了线虫向外层土壤的迁移。添加猪粪的1mm网袋处理经过28d培养后,外层土壤线虫数是空白处理的9.1倍;添加稻草的1mm网袋处理经过35d培养后,外层土壤线虫数是空白处理的5.9倍。添加两种基质的5μm网袋处理,外层土壤线虫数和空白处理差异不大。添加基质主要是促进了食细菌线虫的繁殖,在培养结束时,添加猪粪的1mm网袋处理的食细菌线虫比例达到98.2%,添加稻草的1mm网袋处理的食细菌线虫比例达到90.5%,两个处理食细菌线虫的总数分别是空白处理的14.8倍和8.9倍,并且主要是Protorhabditis sp.线虫的增加。 展开更多
关键词 食细菌线虫 原位富集培养 猪粪 稻草
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