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Hydrologic balance, net primary productivity and water use efficiency of the introduced exotic Eucalyptus grandis × Eucalyptus urophylla plantation in south-western China

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Journal of Plant Ecology 2019年第6期12卷 982-992页

作者： Yanting Hu Ping Zhao Yuqing huang Liwei Zhu Guangyan Ni Xiuhua Zhao Zhihong huang Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of Sciences723 Xingke RoadTianhe DistrictGuangzhou 510650China Guangdong Provincial Key Laboratory of Applied Botany South China Botanical GardenChinese Academy of Sciences723 Xingke RoadTianhe DistrictGuangzhou 510650China Key Laboratory of Beibu Gulf Environment Change and Resource Use Ministry of Education and Guangxi Key Laboratory of Earth Surface Processes and Intelligent SimulationNanning Normal University175 Mingxiu East RoadNanningGuangxi 530001China Department of Forest Ecology College of Life Science and TechnologyCentral South University of Forestry and Technology498 Shaoshan South RoadChangshaHunan 410004China

Aims Land cover changes can disrupt water balance and alter the partitioning of precipitation into surface runoff,evapotranspiration and groundwater *** widely planted Eucalyptus trees in south-western China have the potential to bring about hydrologic *** research aims to elucidate the hydrologic balance characteristics of the introduced exotic Eucalyptus grandis×Eucalyptus urophylla plantation and to assess whether its high productivity results from high water use efficiency(WUE)or large water *** A 400-m^(2) experimental plot was established in an ***×*** plantation in south-western *** balance components,including stand transpiration(T_(r)),evapotranspiration(E_(t))and runoff(R)were obtained as follows:T_(r) was estimated based on sap flow measurements,E_(t) was estimated as the average of surface transpiration and evaporation weighted by the fractional green vegetation cover using a modeling approach,and R was collected using the installed metal *** primary productivity(NPP)was obtained from allometric equation and annual diameter at breast height(DBH)increment *** Findings Annual E_(t) and T_(r) were 430±31 and 239±17 mm,*** T_(r) accounts for 56±8%of total evapotranspiration on ***(NPP/T_(r))of the ***×*** was estimated to be 3.3–3.9 mmol·mol^(−1).Based on the comparative analysis of T_(r) and WUE,***×*** had a high productivity due to its high WUE without exhibiting prodigal water *** factors including vapor pressure deficit and global solar radiation(R_(s))were key factors regulating E_(t) and T_(r) in our research *** surface runoff,E_(t) and canopy interception occupied 7%,27–30%and 16%of total precipitation,while the remaining 46–50%of precipitation was used for sustaining groundwater recharge and altering soil water *** higher runoff coefficient(7.1%)indicated the weaker capability of ***

关键词： water balance evapotranspiration water use efficiency sap flow runoff

HTDcr:a job execution framework for high-throughput computing on supercomputers

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Science China(Information Sciences) 2024年第1期67卷 69-85页

作者： Jiazhi JIANG Dan huang Hu CHEN Yutong LU Xiangke LIAO School of Computer Science and Engineering Sun Yat-sen University School of Software Engineering South China University of Technology

High-throughput computing(HTC) is a computing paradigm that aims to accomplish jobs by easily breaking them into smaller,independent ***,it requires a large amount of computing power for a long *** existing HTC frameworks are job-oriented without support for coscheduling with hardware architecture and task-level ***,most of the frameworks reach a limited scale,and their usability needs further ***,we present HTDcr,a job execution framework for the HTC on *** study aims to improve the throughput,task dispatching,and usability of the *** detail,the throughput optimizations include a sophisticated designed task management system,a hierarchical scheduler,and the co-optimization of the task-scheduling strategy with the application and hardware *** optimizations for usability include a programable execution workflow,mechanisms for more robust and reliable service qualities,and a fine-grained resource allocation system for the colocation of multiple *** to our evaluations,HTDcr can achieve outstanding scalability and high throughput on large-scale clusters for the HTC *** evaluate HTDcr with several microbenchmarks and real-world applications on tianhe-2 and Sunway TaihuLight to demonstrate its effects on existing design *** instance,the task scheduling for two real-world applications integrated with the application and hardware characteristics achieves 1.7× and 1.9× speedups over the basic task-scheduling strategy.

关键词： high-throughput computing supercomputer task scheduling middleware password guessing

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基于SVG的林业信息发布系统研究

测绘信息与工程 2005年第6期30卷 24-25页

作者：黄瑞垠邬群勇池天河陈传彬福州大学福建省空间信息工程研究中心福州市软件大道89号350003

论述了SVG这一基于XML的网络图像技术在WebGIS中的应用,设计和建立了基于SVG的林业信息发布系统的框架,并以福建省漳浦县绥安镇的林业数据为例,对系统加以实现。

关键词：信息发布系统 WebGIS 可伸缩矢量图形林业信息

近距离煤层同采工作面顺槽合理位置的模拟研究

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煤矿安全 2014年第7期45卷 20-22页

作者：李政康官先黄志明康天合太原理工大学采矿工艺研究所山西太原030024

通过数值模拟对华苑煤业9#、10#近距离煤层上部煤层回采形成的侧向支承应力在底板煤岩层中的传递与分布规律及其对下部煤层应力分布的影响进行了研究。研究结果表明,下部煤层工作面顺槽为内错布置时,应布置在距上部煤层侧向煤壁水平距离... 详细信息

通过数值模拟对华苑煤业9#、10#近距离煤层上部煤层回采形成的侧向支承应力在底板煤岩层中的传递与分布规律及其对下部煤层应力分布的影响进行了研究。研究结果表明,下部煤层工作面顺槽为内错布置时,应布置在距上部煤层侧向煤壁水平距离25 m以外;下部煤层工作面顺槽为外错布置时,应布置在距上部煤层侧向煤壁水平距离15 m以外。

关键词：近距离煤层同采顺槽布置侧向应力数值模拟

基于多源数据的城市绿地开放空间体力活动与夏季热环境协同优化研究——以广州为例

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城市发展研究 2022年第11期29卷 27-32+41页

作者：许翔黄鼎曦廖绮晶陈天鹤梁伟东华南理工大学建筑学院广州市城市规划勘测设计研究院广州市城市规划协会广州市从化区人民政府广州市城市规划设计有限公司

健康促进和应对气候变化是当前生态韧性城市建设的两大关注点，城市绿地开放空间在其中发挥了重要的作用，但在规划建设中两者的协同优化研究与实践仍基本处于空白。利用细粒度、长时间序列的多源数据，对广州市夏季代表月开展实证研究... 详细信息

健康促进和应对气候变化是当前生态韧性城市建设的两大关注点，城市绿地开放空间在其中发挥了重要的作用，但在规划建设中两者的协同优化研究与实践仍基本处于空白。利用细粒度、长时间序列的多源数据，对广州市夏季代表月开展实证研究，辨识户外体力活动高吸引地区“体力活动—热环境—空间及形态”耦合特征，发现：（1）降温潜力较大的临湖型公园和高林木覆盖公园对慢速长跑活动吸引度较大，并协同发挥了一定的夏季城市不利热环境缓解作用；室外体育场跑径和高密度城区内一般公园对中短距离跑步活动吸引明显，但仍处于夏季城市不利热环境之中；因此部分绿地开放空间可实现户外体力活动和热环境的协同优化，但此类空间供给不足。（2）样本手机软件用户对热环境舒适度和热环境健康风险不敏感，各聚类代表样本地点承载的超过62%的体力活动的热环境健康风险较高，室外体育场跑径处于“危险”分级的活动占比最高，高密度城区内一般公园处于“极度预警”的活动占比最高，临湖型公园绿地相对最为安全，但日间高温高湿度时段风险比较显著。最后，基于研究发现，对优化城市绿地开放空间的规划建设模式提出策略建议。

关键词：冬暖夏热地区绿地开放空间户外体力活动城市降温健康风险

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高应力大采高厚煤层综采工作面矿压规律研究

矿业安全与环保 2014年第2期41卷 20-23,27页

作者：胡红伟李政康天合黄志明山西长平煤业有限责任公司山西晋城048400 太原理工大学采矿工艺研究所山西太原030024

通过对长平矿4303工作面矿压实测结果的分析,系统研究了大采高工作面的矿压显现规律。研究结果表明：周期来压期间动载系数为1.04~2.01,平均1.35；工作面支架平均工作阻力主要分布在4000~9000 kN,支架增阻效果良好,支架完全能够满足顶... 详细信息

通过对长平矿4303工作面矿压实测结果的分析,系统研究了大采高工作面的矿压显现规律。研究结果表明：周期来压期间动载系数为1.04~2.01,平均1.35；工作面支架平均工作阻力主要分布在4000~9000 kN,支架增阻效果良好,支架完全能够满足顶板支护的要求；提高支架初撑力,有助于提高顶板稳定性。

关键词：大采高综采工艺矿压规律矿压实测高应力厚煤层

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《医学纂要》治咳学术思想探析

山东中医药大学学报 2017年第1期41卷 40-41,44页

作者：凌天和黄振炎广州中医药大学广东广州510405 广州中医药大学附属中山中医院广东中山528400

总结刘渊《医学纂要》治疗咳嗽的学术思想。咳嗽的病因为外感与内伤,无论外感还是内伤咳嗽多伴有咳痰,刘氏在其《痰证辨》中详细阐述了如何辨痰论治咳嗽,对各种咳嗽咳痰的诊治均理法方药具备。其治疗咳嗽又结合岭南人"脾气虚弱兼有痰湿... 详细信息

总结刘渊《医学纂要》治疗咳嗽的学术思想。咳嗽的病因为外感与内伤,无论外感还是内伤咳嗽多伴有咳痰,刘氏在其《痰证辨》中详细阐述了如何辨痰论治咳嗽,对各种咳嗽咳痰的诊治均理法方药具备。其治疗咳嗽又结合岭南人"脾气虚弱兼有痰湿"的体质,因地制宜地辨证论治,提出"治表宜发散外邪,又佐以温解之药;治内伤宜养阴,又兼以纳气温化"的独到见解。

关键词：医学纂要刘渊辨痰咳嗽温热药

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列车信号系统安全距离分析

城市轨道交通研究 2024年第2期27卷 83-87,94页

作者：黄文杰鄢艳丽马天和翟耕慰中车南京浦镇车辆有限公司南京210031 同济大学铁道与城市轨道交通研究院上海201804

[目的]为了解决目前移动闭塞信号系统安全距离计算未考虑故障及低黏着系数等恶劣工况,导致安全距离计算时真实性较差、计算精度较低等问题,需研究不同故障类型和低黏着等恶劣工况对列车信号系统安全距离的影响。[方法]建立了信号系统安... 详细信息

[目的]为了解决目前移动闭塞信号系统安全距离计算未考虑故障及低黏着系数等恶劣工况,导致安全距离计算时真实性较差、计算精度较低等问题,需研究不同故障类型和低黏着等恶劣工况对列车信号系统安全距离的影响。[方法]建立了信号系统安全距离模型,分析了影响列车安全距离的主要因素;综合考虑列车制动系统、列车纵向动力学及轮轨黏着条件,利用MATLAB/Simulink软件搭建包含车载ATP(列车自动防护)触发紧急制动阶段、牵引切除阶段、惰行阶段、紧急制动建立阶段及紧急制动阶段的安全距离仿真平台;结合列车实际参数及相关标准,对超低黏着工况、部分车辆制动力丧失故障工况和不同列车运行速度工况下的信号系统安全距离进行仿真研究。[结果及结论]紧急停车距离是影响信号系统安全距离的主要因素,其与轮轨黏着条件、线路允许最大运行速度和列车可能发生的故障类型有关。当黏着系数为0.03、列车运行速度为120 km/h时,列车正常工况时的安全距离为1520.7 m,最不利工况(故障车为重车、其余为空车时,切除2个转向架)下的安全距离为2196.7 m。实际应用时应考虑测速误差和位置不确定性,为信号系统安全距离留出一定裕量,以保障列车的运行安全。

关键词：轨道交通信号系统安全距离

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Storage wall for exascale supercomputing

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Frontiers of Information Technology & Electronic Engineering 2016年第11期17卷 1154-1175页

作者： Wei HU Guang-ming LIU Qiong LI Yan-huang JIANG Gui-lin CAI College of Computer National University of Defense TechnologyChangsha 410073China National Supercomputer Center in Tianjin Tianjin 300457China

The mismatch between compute performance and I/O performance has long been a stumbling block as supercomputers evolve from petaflops to exaflops. Currently, many parallel applications are I/O intensive,and their overall running times are typically limited by I/O performance. To quantify the I/O performance bottleneck and highlight the significance of achieving scalable performance in peta/exascale supercomputing, in this paper, we introduce for the first time a formal definition of the ‘storage wall' from the perspective of parallel application scalability. We quantify the effects of the storage bottleneck by providing a storage-bounded speedup,defining the storage wall quantitatively, presenting existence theorems for the storage wall, and classifying the system architectures depending on I/O performance variation. We analyze and extrapolate the existence of the storage wall by experiments on tianhe-1A and case studies on Jaguar. These results provide insights on how to alleviate the storage wall bottleneck in system design and achieve hardware/software optimizations in peta/exascale supercomputing.

关键词： Storage-bounded speedup Storage wall High performance computing Exascale computing