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Carbon allocation in Picea jezoensis:Adaptation strategies of a non-treeline species at its upper elevation limit

Forest Ecosystems 2024年第3期11卷 347-357页

作者： Renkai Dong Na Li Mai-He Li Yu Cong haibo du Decai Gao Hong S.He Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun130024China School of Natural Resources University of MissouriColumbiaMO65211USA Swiss Federal Institute for Forest Snow and Landscape Research WSL8903BirmensdorfSwitzerland Northeast Institute of Geography and Agricultural Ecology Chinese Academy of SciencesChangchun130102China School of Life Science Hebei UniversityBaoding071002China

Understanding the physiological adaptations of non-treeline trees to environmental stress is important to understand future shifts in species composition and distribution of current treeline *** aim of the present study was to elucidate the mechanisms of the formation of the upper elevation limit of non-treeline tree species,Picea jezoensis,and the carbon allocation strategies of the species on Changbai *** employed the^(13)C in situ pulse labeling technique to trace the distribution of photosynthetically assimilated carbon in Picea jezoensis at different elevational positions(tree species at its upper elevation limit(TSAUE,1,700 m a.s.l.)under treeline ecotone;tree species at a lower elevation position(TSALE,1,400 m a.s.l.).We analyzed^(13)C and the non-structural carbohydrate(NSC)concentrations in various tissues following *** findings revealed a significant shift in carbon allocation in TSAUE compared to *** was a pronounced increase inδ^(13)C allocation to belowground components(roots,soil,soil respiration)in TSAUE compared to ***,the C flow rate within the plant-soil-atmosphere system was faster,and the C residence time in the plant was shorter in *** trends indicate enhanced C sink activity in belowground tissues in TSAUE,with newly assimilated C being preferentially directed there,suggesting a more conservative C allocation strategy by *** at higher elevations under harsher *** a strategy,prioritizing C storage in roots,likely aids in withstanding winter cold stress at the expense of aboveground growth during the growing season,leading to reduced growth of TSAUE compared to *** results of the present study shed light on the adaptive mechanisms governing the upper elevation limits of non-treeline trees,and enhances our understanding of how non-treeline species might respond to ongoing climate change.

关键词： ^(13)C pulse labeling Carbon distribution Non-structural carbohydrates(NSC) Non-treeline species Sink activity Stressful environments Upper elevation limit

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长三角城市快递物流联系网络及空间平衡格局研究

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地理科学进展 2024年第7期43卷 1307-1319页

作者：葛迎遨杨山杜海波南京师范大学地理科学学院南京210023 江苏省地理信息资源开发与利用协同创新中心南京210023

伴随着全球化和信息化的加速发展,快递物流联系网络已经成为城市网络的重要组成部分。论文基于不同月份(6、8、11月)的城市快递物流数据,运用PageRank算法、节点对称性、链接对称性、QAP分析法等方法,从城市联系、城市节点的层级差异特... 详细信息

伴随着全球化和信息化的加速发展,快递物流联系网络已经成为城市网络的重要组成部分。论文基于不同月份(6、8、11月)的城市快递物流数据,运用PageRank算法、节点对称性、链接对称性、QAP分析法等方法,从城市联系、城市节点的层级差异特征、空间平衡格局,城市联系网络的影响因素方面对长三角城市快递物流联系网络进行了探究,得出以下结论:①长三角城市快递物流联系网络的时空差异特征明显,其在空间分布上具有层级性,呈现以苏州—上海、上海—苏州、杭州—上海、上海—杭州、金华—杭州、金华—上海等城市联系为核心的“核心—边缘”格局;在时间分布上具有波动性,11月的城市联系强度大于6月与8月。②根据三个时段的城市节点PageRank平均值大小,长三角城市可划分为三个层级,以上海为中心的包含杭州、苏州、南京、合肥、金华、宁波等城市在内的第一层级城市在空间上呈“弓”字形分布。③从城市节点空间平衡格局来看,长三角城市节点平衡类型以流入型为主,三个时段中流入型城市占比均超过60%。④从城市链接空间平衡格局来看,不同平衡等级下城市链接的空间分布情况存在一定差异。在一级平衡的城市链接中,区域南北方向间的平衡程度大于东西方向间的平衡程度;在五级平衡的城市链接中,区域中形成了以金华为主的快递物流辐射中心。⑤根据QAP分析结果,年末常住人口、第三产业增加值、城镇常住居民人均可支配收入对城市快递物流联系具有正向影响。研究可为有向加权的城市网络研究及长三角快递物流一体化发展提供参考依据。

关键词：快递物流城市联系网络空间平衡格局长三角

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矿用烟雾传感器的抗干扰设计与试验研究

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煤矿机械 2024年第3期45卷 51-54页

作者：杜海波中煤科工集团杭州研究院有限公司杭州311201

针对传统技术路线矿用烟雾传感器工作在高尘工作面环境易受干扰发出误报警的问题,分析了现有技术路线的局限,提出使用双波长光电感烟敏感元件作为检测核心,采集散射光响应及其比例值作为原始数据,以烟雾气溶胶粒径尺寸为判据判定其性质... 详细信息

针对传统技术路线矿用烟雾传感器工作在高尘工作面环境易受干扰发出误报警的问题,分析了现有技术路线的局限,提出使用双波长光电感烟敏感元件作为检测核心,采集散射光响应及其比例值作为原始数据,以烟雾气溶胶粒径尺寸为判据判定其性质是否为火灾烟雾气溶胶。通过双阈值判断算法实现了在提升样机抗干扰性能的同时保证其检测的高灵敏度,并优化了气室设计以提升其防护能力。经实验室测试,传感器样机具备高灵敏度和对短暂扫过喷水流的防护能力。样机在工业现场高尘工作面环境实际测试中未出现误报警现象,可正确响应标校烟雾试剂,能够满足高尘工作面火灾烟雾检测的需求。

关键词：矿用烟雾传感器高尘工作面双波长光电感烟抗干扰试验研究

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中医住培基地住培医生纯中医诊疗能力培养的问题与对策

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中国中医药现代远程教育 2024年第2期22卷 194-196页

作者：杜海波长春中医药大学附属医院心病中心吉林长春130021

全国268家中医住院医师规范化培训(以下简称“住培”)基地、协同单位和基层培养基地是培养中医临床医生的摇篮。中医住培自开展以来,取得了丰硕的成果,但同时也暴露出一些问题,尤其是中医住培基地在培养住培医生纯中医诊疗能力方面面临... 详细信息

全国268家中医住院医师规范化培训(以下简称“住培”)基地、协同单位和基层培养基地是培养中医临床医生的摇篮。中医住培自开展以来,取得了丰硕的成果,但同时也暴露出一些问题,尤其是中医住培基地在培养住培医生纯中医诊疗能力方面面临一些问题与挑战,需要制定相应的对策予以解决,以全面提升住培医生的纯中医诊疗能力。

关键词：中医住培基地住培医生纯中医诊疗能力

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Global finite-time attitude regulation using bounded feedback for a rigid spacecraft

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Control Theory and Technology 2017年第1期15卷 26-33页

作者： Yusong ZHOU Wenwu ZHU haibo du Anhui Vocational College of Press and Publishing Hefei Anhui 230601 China School of Electrical Engineering and Automation Hefei University of Technology Hefei Anhui 230009 China

This paper investigates the problem of global attitude regulation control for a rigid spacecraft under input saturation. Based on the technique of finite-time control and the switching control method, a novel global bounded finite-time attitude regulation controller is proposed. Under the proposed controller, it is shown that the spacecraft attitude can reach the desired attitude in a finite time. In addition, the bound of a proposed attitude controller can be adjusted to any small level to accommodate the actuation bound in practical implementation.

关键词： Global attitude regulation finite-time control bounded feedback

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Finite-Time Output Feedback Control for DC-DC Buck Power Converters System

Finite-Time Output Feedback Control for DC-DC Buck Power Con...

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第36届中国控制会议

作者： Yeyuan Xu haibo du School of Electrical Engineering and Automation Hefei University of Technology

ISBN: (纸本)9781538629185

This paper investigates the finite-time output feedback control problem for DC-DC buck converter systems. By using the techniques of finite-time controller and finite-time convergent observer, a new fast voltage regulation control algorithm is designed which can guarantee that the output voltage converges to the reference voltage in the finite time. An inductive current convergent observers has been designed to estimate the unknown current in the finite time. Compared with the PI control algorithm, simulation results show that the proposed algorithm has a faster regulation performance under the condition of loadvariation and reference voltage change.

关键词： DC-DC Buck Converter Finite-time Control Output Feedback Control Inductive Current Observer

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Finite-Time Position Tracking Control of a Quadrotor Aircraft

Finite-Time Position Tracking Control of a Quadrotor Aircraf...

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第36届中国控制会议

作者： Di Wu haibo du Wenwu Zhu School of Electrical Engineering and Automation Hefei University of Technology

ISBN: (纸本)9781538629185

This paper proposes a finite-time control law for quadrotor aircraft to achieve position tracking control in a finite ***, the position dynamical equation and the attitude dynamical equation are introduced respectively. Secondly, based on the technique of finite-time control, a finite-time position controller is designed to ensure the desired trajectory can be tracked by the real position in a finite time. Then, a finite-time attitude controller is designed which can guarantee that the desired attitude can be tracked in a finite time. Finally, to show effectiveness of the proposed method, a simulation example is given.

关键词： Quadrotor aircraft Tracking Control Finite-time control

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Impact of historical pattern of human activities and natural environment on wetland in Heilongjiang River Basin

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Frontiers of Environmental Science & Engineering 2023年第12期17卷 123-136页

作者： Chaoxue Song Hong S.He Kai Liu haibo du Justin Krohn Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun 130024China School of Natural Resources University of MissouriColumbiaMO 65211USA Center for Applied Research and Engagement Systems University of MissouriColumbiaMO 65211USA

Mid and high latitude wetlands are becoming fragmented and losing ecosystem functions at a much faster rate than many other *** is due in part to increasing human activities and climate *** this study,we analyzed wetland distribution and spatial pattern changes for the Heilongjiang River Basin over the past 100 *** identified the driving factors and quantified the relative importance of each factor based on landscape pattern metrics and machine learning *** results show that wetlands have been fragmented into smaller and regular patches with dominant factors that varied at different *** features play the most important role in patterns of wetland change for the entire basin(with 50%-60%of relative importance).Human activities are more important than climate change at the century scale,but less important when magnified at the decadal *** the early 1900s,human activities were relatively low and localized and remained that way in the subsequent ***,the effect of human activities on wetland area of the entire basin is weaker when examined at the magnified decadal *** results also show that human activities are more important on the Chinese side of the Heilongjiang River Basin,in the ZeyaBureya Plain on the Russian side,and at lower altitudes(0-100 m).Revealing the spatial and temporal processes and driving factors over the past 100 yr helps researchers and policymakers understand and anticipate wetland change and design effective conservation and restoration policies.

关键词： Wetland change Human activities Climate change Driving mechanism Heilongjiang River Basin

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高铁精品站房施工实践

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铁路技术创新 2024年第3期 82-90页

作者：张卫红刘洪河杜海波中铁北京工程局集团有限公司北京102308 中铁北京工程局集团北京有限公司北京100070

按照中国国家铁路集团有限公司“畅通融合、绿色温馨、经济艺术、智能便捷”建设新理念,我国建造了一批精美的铁路客站精品工程和示范工程。基于潜山站、河池西站、鄱阳站等中小型高铁客站施工建设经验,总结打造精品站房的施工组织管理... 详细信息

按照中国国家铁路集团有限公司“畅通融合、绿色温馨、经济艺术、智能便捷”建设新理念,我国建造了一批精美的铁路客站精品工程和示范工程。基于潜山站、河池西站、鄱阳站等中小型高铁客站施工建设经验,总结打造精品站房的施工组织管理措施,通过强化施工过程管理,保证精品工程质量;将地域文化元素分为自然、历史、民俗和建筑4类,阐述地域文化元素精准融入高铁站房中的施工方法,精准呈现设计意图,弘扬地域文化;围绕“重结构、轻装饰、简装修”建筑做法要求,介绍部分精细化施工工程经验,保证站房美观兼具实用;提出站房工艺工法创新,从科技创新角度助力实现站房精品。

关键词：高铁精品站房地域文化中小型客站精细化施工

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Power in Job Interview

Power in Job Interview

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作者： du haibo 广东外语外贸大学

学位级别：硕士

Based upon the theoretical framework of critical discourse analysis put forward by Fairclougb., the present work attempts to study power in job interviews, or we can say that it t... 详细信息

Based upon the theoretical framework of critical discourse analysis put forward by Fairclougb., the present work attempts to study power in job interviews, or we can say that it tries to approach job interviews in terms of power. The research is based upon authentic data recorded on-site. 13 job interviews are recorded. All of the interviewees are university graduates, and the interviewers represent organizations in different circles of business in Ciuangzhou. during the process of analyzing data, we noticed the distinctions among job interviews, which led us to categorize them into what we call preliminary job interviews and official job interviews. The findings are: （i） The role as questioner or responder shifts in preliminary job interviews and stays largely unchanged in official job interviews, and the interviewer and the interviewee’s length of turns are closely related with that;（ii） The interviewee’s one-way promotion features official job interviews, and mutual promotion is often found in preliminary job interviews;（iii） There is the influence of knowledge in job interviews. The following socially orienied leads us to draw the three conclusions below: （i） The existence of relations of power is evident in job interviews

关键词： Pro

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