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Early-Holocene Paleo-Tropical Cyclone Activity Inferred from a Sedimentary Sequence in South Yellow Sea,East Asia

Journal of Earth Science 2022年第3期33卷 789-801页

作者： Geng Liu xibin han Yanping Chen Jun Li Lehui Song Xin Zhou Bangqi Hu Liang Yi MNR Key Laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Zhejiang Academy of Marine Sciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China MNR Key Laboratory of Marine Hydrocarbon Resources and Environmental Geology Qingdao Institute of Marine GeologyChina Geological SurveyQingdao 266071China School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Laboratory for Marine Mineral Resources Pilot National Laboratory for Marine Science and TechnologyQingdao 266071China State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China Wuhan Center China Geological SurveyWuhan 430205China

Although tropical cyclones play a critical role in global climate changes,their long-term variations in the past are not well documented.In this article,a sediment core from the South Yellow Sea was studied in order to reveal the influence of tropical cyclones on depositional processes.Integrating the results of radiocarbon dating and sediment grain-size analysis,we show that the studied sequence was deposited during the Holocene and the sedimentary dynamics were stable and at a relatively low level,with a median grain-size range of 5.3-8.7μm.It is found that coarse particles were likely transported by highly dynamic depositional events.Based on the findings,a record of paleo-tropical cyclones was derived for the Early Holocene,and several intervals with a reduced influence of tropical cyclones were identified.In addition,it reveals a good agreement between the grain-size results and the changes in solar activity,monsoonal intensity,and the El Ni?o-Southern Oscillation.Overall,it can be concluded that the influence of tropical cyclones on the sedimentary evolution of the muddy zone of the South Yellow Sea was substantial during the Early Holocene on centennial timescales,and that solar maxima may control the intensity of tropical cyclones via strengthening the walker circulation over the tropical Pacific.

关键词： the Yellow Sea Early Holocene tropical cyclone sedimentary process sediment grain size solar activity

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Biomarker records of D5-6 columns in the eastern Antarctic Peninsula waters:responses of planktonic communities and bio-pump structures to sea ice global warming in the past centenary

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Advances in Polar Science 2021年第1期32卷 28-41页

作者： YANG Dan ZhanG Haisheng han Zhengbing HAN Xibin ZhanG Yicheng CHEN Wensheng LIU Qian PAN Jianming FAN Gaojing LE Fengfeng LU Bing HUANG Jing Key Laboratory of Marine Ecosystem and Biogeochemistry Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Key Laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Zhuhai Central Station of Marine Environmental Monitoring State Oceanic AdministrationZhuhai 519015China Polar Research Institute of China Shanghai 200136China*

Molecular biomarkers(e.g.,isoprenoid glycerol dialkyl glycerol tetraethers(iGDGTs)and proxies,such as di-unsaturated to tri-unsaturated highly branched isoprenoids(D/T)ratio,total organic carbon,δ^(13)C and ice-rafted debris(IRD))were used to reconstruct the dominant phytoplankton(diatoms,dinoflagellates and coccolithophores),phytoplankton and zooplankton productivity,biological pump structure,and archaea assemblage(Euryarchaeota and Crenarchaeota)from a marine sediment core(D5-6)dated with^(210)Pb(1922–2012).We characterized the environmental response to sea ice variations/global warming off the eastern Antarctic Peninsula.The results showed that(1)the biomarkers brassicasterol(average=519.79 ng·g^(-1)),dinosterol(average=129.68 ng·g^(-1))and C37 alkenones(average=40.53 ng·g^(-1))reconstructed phytoplankton(average=690.00 ng·g^(-1))and zooplankton(cholesterol average=669.25 ng·g^(-1))productivity.The relative contribution to productivity by different phytoplankton groups was diatoms>dinoflagellates>coccolithophores.This is consistent with field surveys showing that diatoms dominate the phytoplankton in waters adjacent to the Antarctic Peninsula.(2)The relative abundances of different highly branched isoprenoids reflected the contributions of sea ice algae and open water phytoplankton(D/T=1.2–30.15).Phytoplankton productivity and sea ice showed a good linear relationship with a negative correlation,indicating that more open water during periods of warming and reduced sea ice cover led to an enhanced biological pump.(3)Over the past 100 years,phytoplankton productivity and zooplankton biomass increased.This trend was particularly evident in the last 50 years,corresponding to increased global warming,and showed a negative correlation with IRD and D/T.This suggests that with decreasing sea ice coverage in a warming climate,diatom biomass greatly increased.Coccolithophore/diatom values and the ratio of C37 alkenones to total phytoplankton productivity decreased,indicating the proportion of coccolithophores in the phy

关键词： global warming phytoplankton productivity zooplankton productivity archaea iGDGTs sea ice proxy D/T eastern Antarctic Peninsula

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浅析人工挖孔桩在中分化泥岩中的应用

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工程质量 2023年第7期41卷 46-50,59页

作者：韩喜斌甘肃省核地质二一二大队核工业武威工程勘察有限公司甘肃武威733000

随着建筑工程和科学技术的发展与进步,桩基工程先进的设计思路和施工技术得到广泛推广,在工程中的应用也越来越多,对复杂地层的基础施工也越来越成熟。论文通过实践工程,论述了人工挖孔桩在中分化泥岩中的应用,分析了人工挖孔在工程中... 详细信息

随着建筑工程和科学技术的发展与进步,桩基工程先进的设计思路和施工技术得到广泛推广,在工程中的应用也越来越多,对复杂地层的基础施工也越来越成熟。论文通过实践工程,论述了人工挖孔桩在中分化泥岩中的应用,分析了人工挖孔在工程中的专业技术要求。

关键词：建筑工程设计思路桩基工程挖孔桩泥岩

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信息时代职业教育混合教学要素及其关系

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电化教育研究 2022年第2期43卷 19-25,41页

作者：王雯韩锡斌中国教育科学研究院北京100088 清华大学教育研究院北京100084

职业教育“三教”(即教师、教材、教法)改革是职业教育深化内涵建设的切入点和突破口,但教学是个多要素的复杂系统,教学系统内部的矛盾性和信息时代外部环境的变化,都要求对教学系统各要素及其关系进行整体化认识。综合已有理论和相关... 详细信息

职业教育“三教”(即教师、教材、教法)改革是职业教育深化内涵建设的切入点和突破口,但教学是个多要素的复杂系统,教学系统内部的矛盾性和信息时代外部环境的变化,都要求对教学系统各要素及其关系进行整体化认识。综合已有理论和相关研究成果,阐明了信息时代职业教育混合教学具有七个要素,包括学生、教师两个主体要素,教学目标、教学内容、教学方法、教学反馈四个过程要素,教学环境一个环境要素。与基础教育和高等教育相同的是,这些要素的内涵在信息时代混合教学中向虚实融合方向拓展;不同的是,这些要素蕴含着职业教育“校企合作、产教融合、工学结合”的显著特征,七个要素间存在既相互支撑又相互约束的辩证关系。应以信息时代技术技能人才培养目标作为职业教育“三教”改革的出发点,立足“互联网+职业教育”的工学环境,面向职教学生的特点和学习需要,提升教师信息化“双师”教学能力,建设活页式、工作手册式、融媒体教材,选择恰当的混合教法,以数据化绩效考核的教学反馈连通教学改革的闭环,实现教学系统的有效运转与行动优化。

关键词：职业教育混合教学教学要素信息时代 “三教”改革

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国家中小学智慧教育平台赋能农村义务教育高质量发展

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中国电化教育 2023年第8期 7-17页

作者：杜江韩锡斌宜宾学院教育学部四川宜宾644000 清华大学教育研究院北京100084

教育数字化转型已成为化解人民日益增长的优质教育需求与不平衡不充分的教育发展之间矛盾的重要突破口。作为国家教育数字化战略行动的重要抓手,国家中小学智慧教育平台的建设和应用,为加速推进农村义务教育优质均衡发展和城乡一体化提... 详细信息

教育数字化转型已成为化解人民日益增长的优质教育需求与不平衡不充分的教育发展之间矛盾的重要突破口。作为国家教育数字化战略行动的重要抓手,国家中小学智慧教育平台的建设和应用,为加速推进农村义务教育优质均衡发展和城乡一体化提供了新的机遇。该文通过文献研究、理论分析和经验总结等方法,在明晰农村义务教育基本情况,分析农村义务教育信息化研究与实践状况,梳理国家中小学智慧教育平台建设成就与优势的基础上,以创新扩散理论和扩展的技术接受和使用统一理论为分析框架,构建了国家中小学智慧教育平台赋能农村义务教育发展的框架,讨论了平台赋能农村义务教育发展的关键路径。

关键词：教育数字化转型国家中小学智慧教育平台农村义务教育框架构建关键路径

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Distribution and Sources of Polycyclic Aromatic Hydrocarbons in the Sediment Cores M2 from the Prydz Bay and Implications for Sedimentary Environment

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Meteorological and Environmental Research 2019年第4期10卷 15-22页

作者： Yang Dan HAN Xibin Zhang Haisheng Zhang Yicheng Xu Xudan Zhang Huijuan Key Laboratory of Marine Ecosystem and Biogeochemistry Second Institute of Oceanography Ministry of Natural Resources Hangzhou 310012 China Key Laboratory of Submarine Geosciences Second Institute of Oceanography Ministry of Natural Resources Hangzhou 310012 China

In this study, the polycyclic aromatic hydrocarbons (PAHs) from the sediment cores M2 in the Pryza Bay of the Antarctica were quantitatively measured using GC-MS analysis, and it is found that the PAHs mainly included bicyclic naphthalene compounds, tricyclic phenanthrene and fluorine series (dibenzofuran and dibenzothiophene), and tetracyclic fluoranthene, pyrene and chrysene series. The results showed that the phenanthrene series with low molecular weight (tricyclic compounds) had a relatively higher content than the series with high molecular weight (tetracyclic compounds). The fluoranthene/(fluoranthene and pyrene) ratio of M2 varied from 0.46 to 0.54. Integrated with the content of 1,7-dimethylphenanthrene and terrigenous chrysene, it is inferred that PAHs in the sediments from the Pryzd Bay were originated from a mixed source of the products of petroleum, refined products and coal combustion, natural source and terrigenous higher plants. Complete methyl dibenzothiophene and dimethyldibenzothiophene series compounds were detected in the sediment cores, which are closely associated with a reducing environment. The ratio of dibenzothiophene to dibenzofuran was between 0.46 and 3.21, mostly greater than 0.7. Combined with the oxidation/reduction index (Pr/Ph) ranging from 0.45 to 0.61 for the sediment cores, it is indicated that these compounds were formed in a normal reducing environment. Geochemical parameters of PAHs such as TNR-1 (0.53-1.57), MPI (0.24-1.21), MDR (1.83-5.57), and MDBI (0.41-0.93), and maturity parameters such as C 29 /C 29 (+), C 31 22S/C 31 (22S+22R), C 32 22S/C 32 (22S+22R) and Ts/(Tm+Ts) were all indicative of high maturity. However, all the above parameters were significantly deviated from those of modern sediments and modern organisms, which undoubtedly shows the input of exogenous mature organic matter.

关键词： Antarctica Sediment core Polycyclic aromatic hydrocarbons Material source Sedimentary environment

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Application o f 210 Pb, Carbon and Nitrogen Isotope in Tracing of Changes and Burial Effect of Endogenous and Terrigenous Organic Matter in the Bering Sea over the Past 100 Years

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Meteorological and Environmental Research 2017年第5期8卷 111-117页

作者： Zhang Haisheng Chen Jianfang han Zhengbing HAN Xibin Xu Xudan Fan Gaojing Lu Bing Second Institute of Oceanography State Oceanic AdministrationHangzhou 310012China Key Laboratory of Marine Ecosystem and Biogeochemistry State Oceanic AdministrationHangzhou 310012China Key Laboratory of Submarine Geosciences State Oceanic AdministrationHangzhou 310012China

By using the multi-tube sediment samples collected from NB01 station in the Bering Sea during the period of the fourth Chinese Arctic research expedition in 2010,as well as the dating technique of radioisotope ^(210)Pb in sedimentary strata,based on the exponential decay trend of ^(210)Pb exwith the column sample depth,relative stable modern sedimentary environment in the investigation area was reflected. The results show that the deposition rate of modern marine sediment S was 0. 27 cm/a,and correlation coefficient R was 0. 96( n = 17),while time span was 107 a(1903-2010). Meanwhile,carbon,nitrogen and isotopes were used to trace the sources of materials in the Bering Sea. It is found that the content of organic carbon and nitrogen in the column samples from NB01 station in the Bering Sea was 1. 18%-1. 80% and 0. 16%-0. 28% respectively,and C/N ratio ranged from 5. 13 to 8. 31. Total organic carbon( TOC) and total organic nitrogen( TON) were preserved well in sedimentary strata and had good consistency,showing that sources of organic matter were consistent. Moreover,their changes positively correlated with^(210)Pb. Organic carbon isotope( δ13 C) ranged from-22. 45‰ to-21. 82‰,and its changing trend was similar to that of C/N ratio; organic nitrogen isotope(δ15 N) varied from 7. 53‰ to 8. 54‰,indicating that organic matter was mainly from remaining marine organisms after being decomposed,into which a certain quantity of terrigenous materials were mixed. In the 100 years,the overall trend of terrigenous materials became increasingly obvious,showing that the input and burial of organic carbon from seas and land in the Bering Sea were changing. According to the burial rate of surface sediment and content of organic carbon,the apparent burial flux of sedimentary organic carbon in the column sample from NB01 station in the Bering Sea was estimated,about 1 450 mmol C/( m^2·a). It is suggested that the high burial flux of sedimentary organic carbon in the regions was mainly related to the high primary productivity of th

关键词： The Arctic The Bering Sea 210Pb Deposition rate Organic carbon and nitrogen isotope Sources of materials

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混合课程学生成绩预测模型的可解释性探究

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中国远程教育 2022年第6期 46-55页

作者：罗杨洋韩锡斌兰州大学高等教育研究院 730000 清华大学教育研究院 100084

机器学习技术的可解释性是人工智能与教育教学深度融合的关键所在。打开机器学习模型的“黑箱”,理解机器学习模型结构的教育意义、推理的机制和预测结果的应用条件是实现人机互信的基础,也是促进人工智能在教育教学中应用的前提条件。... 详细信息

机器学习技术的可解释性是人工智能与教育教学深度融合的关键所在。打开机器学习模型的“黑箱”,理解机器学习模型结构的教育意义、推理的机制和预测结果的应用条件是实现人机互信的基础,也是促进人工智能在教育教学中应用的前提条件。本研究以五种基于机器学习算法构建的学生成绩预测模型为例,分析了混合教学场景中解释学生成绩预测模型主要关注的三个方面:预测模型结构所代表的教育意义、预测模型内在推理机制所揭示的预测关系和预测结果对教学实践的启示。结果发现:(1)只采用学生的部分学习过程数据预测学习成绩时,学生的行为模式与学习成绩的映射关系存在多种模式,试图构建学生在线行为与学生成绩一一对应关系的预测模型难以获得较好的预测结果;(2)本研究中的预测模型最高可预测正确所有混合课程中74.7%的学生,不同学习成绩组学生的预测准确率差异较大,成绩为A和B的学生预测准确率较高,达到80.6%和85.3%,成绩为C及以下的学生预测准确率最高只达到63%;(3)本研究中的预测模型对学生个体的预测结果只有当学生积极参加所有在线学习活动时才具有较高可信度,当学生个体出现在线学习活动缺失时预测结果可信度较低。研究还对教师在混合课程场景下如何应用成绩预测模型提供了建议:(1)针对混合课程的特点应用预测结果;(2)理解模型的推理机制以灵活切换预测模型;(3)依据学生在线学习行为参与的完整性判断预测结果是否可信。

关键词：学习分析混合课程机器学习算法预测模型可解释性逻辑回归多层感知器随机森林多核支持向量机朴素贝叶斯

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Shifting from homogeneous to heterogeneous surfaces in estimating terrestrial evapotranspiration: Review and perspectives

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Science China Earth Sciences 2022年第2期65卷 197-214页

作者： Yuanbo LIU Guoyu QIU Hongsheng ZhanG Yonghui YANG Yinsheng ZhanG Quan WANG Wenzhi ZHAO Li JIA xibin JI Yujiu XIONG Chunhua YAN Ning MA Shumin han Yifan CUI Nanjing Institute of Geography and Limnology Chinese Academy of SciencesNanjing 210008China School of Environment and Energy Peking University Shenzhen Graduate SchoolShenzhen 518055China Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100081China Key Laboratory for Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050022China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China Faculty of Agriculture Shizuoka UniversityShizuoka 422-8529Japan Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China Key Laboratory of Ecohydrology of Inland River Basin Chinese Academy of SciencesLanzhou 730000China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China School of Civil Engineering Sun Yat-Sen UniversityGuangzhou 510275China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Terrestrial evapotranspiration(ET)is a crucial link between Earth’s water cycle and the surface energy budget.Accurate measurement and estimation remain a major challenge in geophysical,biological,and environmental studies.Pioneering work,represented by Dalton and Penman,and the development of theories and experiments on turbulent exchange in the atmospheric boundary layer(ABL),laid the foundation for mainstream methodologies in ET estimation.Since the 1990s,eddy covariance(EC)systems and satellite remote sensing have been widely applied from cold to tropical and from arid to humid regions.They cover water surfaces,wetlands,forests,croplands,grasslands,barelands,and urban areas,offering an exceptional number of reports on diverse ET processes.Surface nocturnal ET,hysteresis between ET and environmental forces,turbulence intermittency,island effects on heterogeneous surfaces,and phase transition between underlying surfaces are examples of reported new phenomena,posing theoretical and practical challenges to mainstream ET methodologies.Additionally,based on non-conventional theories,new methods have emerged,such as maximum entropy production and nonparametric approaches.Furthermore,high-frequency on-site observation and aerospace remote sensing technology in combination form multi-scale observations across plant stomata,leaves,plants,canopies,landscapes,and basins.This promotes an insightful understanding of diverse ET processes and synthesizes the common mechanisms of the processes between and across spatial and temporal scales.All the recent achievements in conception,model,and technology serve as the basis for breaking through the known difficulties in ET estimation.We expect that they will provide a rigorous,reliable scientific basis and experimental support to address theoretical arguments of global significance,such as the water-heat-carbon cycle,and solve practical needs of national importance,including agricultural irrigation and food security,precise management of water resources and eco-environmental prot

关键词： Evapotranspiration Atmospheric boundary layer Heterogeneous surface Uncertainty

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高校教师信息化教学能力培训迁移的分析框架

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中国电化教育 2018年第4期 17-25页

作者：姜蔺韩锡斌清华大学教育研究院北京100084

对在职教师而言,教师培训是促进教师专业发展的一种有效途径,教师培训的有效性直接影响教师信息化教学能力的提升效果及专业发展水平。大多数教师培训研究更多关注培训结束时教师的学习结果和主观感受,然而教师培训后是否能够真正学以致... 详细信息

对在职教师而言,教师培训是促进教师专业发展的一种有效途径,教师培训的有效性直接影响教师信息化教学能力的提升效果及专业发展水平。大多数教师培训研究更多关注培训结束时教师的学习结果和主观感受,然而教师培训后是否能够真正学以致用,即培训迁移问题尚有待深入研究。该文借鉴企业人力资源管理领域的研究成果,系统梳理了培训迁移的概念、过程、影响因素以及效果评价,并综述了高校教师信息化教学能力培训迁移的研究现状。文章进一步界定了高校教师信息化教学能力培训迁移过程的范围,并从培训迁移的过程、影响因素、培训效果评价三个方面提出了高校教师信息化教学能力培训迁移的分析框架,其中培训迁移的过程不仅要包括学习结束后的教学应用阶段,还要包括培训学习阶段这一前提且贯穿教学应用过程的阶段;影响因素方面主要包括教师特征、培训干预、学校环境三部分;培训效果评价方面主要包括培训学习结果评价与教学应用结果评价;在分析框架中,迁移动机既是培训学习阶段与教学应用阶段的中间结果,又是影响因素与教学应用阶段的中间环节。

关键词：教师信息化教学能力教师培训培训迁移文献综述

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