检索结果-南通市图书馆

Hotspots of the sensitivity of the land surface hydrological cycle to climate change

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2013年第28期58卷 3682-3688页

作者： HUA WenJian CHEN HaiShan zhu siguang SUN ShanLei YU Miao ZHOU LiMing Key Laboratory of Meteorological Disaster Ministry of EducationNanjing University of Information Science & Technology College of Global Change and Earth System Science Beijing Normal University Applied Hydrometeorological Research Institute Nanjing University of Information Science & Technology Department of Atmospheric and Environmental Sciences University at AlbanyState University of New York

Due to the shortage of the global observational data of the terrestrial hydrological variables,the understanding of how surface hydrological processes respond to climate change is still limited.In this study,the Community Land Model(CLM4.0)with high resolution atmospheric forcing data is selected to simulate the global surface hydrological quantities during the period 1948–2006and to investigate the spatial features of these quantities in response to climate change at the regional scales.The sensitivities of evaporation and runoff with respect to the dominant climate change factors(e.***.temperature and precipitation)derived from the concept of climate elasticity are introduced.Results show that evaporation has a declining trend with a rate of 0.7 mm per decade,while runoff shows a weak increasing trend of 0.15 mm per decade over the global land surface.Analyses of the hotspots in the hydrological cycle indicate that the spatial distributions for evaporation and runoff are similar over many areas in central Asia,Australia,and southern South America,but differ largely in high latitudes.It is also found that,the evaporation hotspots in arid regions are mainly associated with the changes in precipitation.Our sensitive analysis suggests that the hydrological quantities show a rather complicated spatial dependency of response of the water cycle to the different climate factors(temperature and precipitation).

关键词：敏感性分析气候变化水文循环陆地表面空间特征高纬度地区蒸发率水文变量

再分析资料和CESM模式模拟的表层土壤湿度次季节变率

在线全文

学校读者我要写书评

暂无评论

Atmospheric and Oceanic Science Letters 2020年第1期13卷 34-40页

作者： WANG Yudan CHEN Haishan ZHOU Yang DONG Xuan zhu siguang Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of EducationNanjing University of Information Science&TechnologyNanjingChina

利用欧洲中心(ERA-Interim)和美国气候预测系统(CFSR)再分析资料,结合地球系统模式CESM的模拟结果,考察了1979–2016年全球表层土壤湿度次季节变率的基本特征。在各个季节和所有资料中,土壤湿度均有明显的次季节变率,且有明显的区域和... 详细信息

利用欧洲中心(ERA-Interim)和美国气候预测系统(CFSR)再分析资料,结合地球系统模式CESM的模拟结果,考察了1979–2016年全球表层土壤湿度次季节变率的基本特征。在各个季节和所有资料中,土壤湿度均有明显的次季节变率,且有明显的区域和季节性差异。在中国东部、北美、南非、澳大利亚的夏季,土壤湿度有较大的次季节方差,CFSR和CESM中的土壤湿度变率强于ERA-Interim。通过谱分析,发现中国东部和南非的土壤湿度主要为10–30天的周期,北美和澳大利亚的土壤湿度同时具有10–30天和30–50天的周期。

关键词：土壤湿度次季节变率陆–气相互作用

Congestion Relief in Downlink OFDMA Cellular System Using Inter-Cell Relay

在线全文

学校读者我要写书评

暂无评论

China Communications 2019年第4期16卷 35-46页

作者： Weifeng Lu Mingqi zhu Jia Xu siguang Chen Lijun Yang Jian Xu School of Computer Science Nanjing University of Posts and Telecommunications Jiangsu Key Laboratory of Big Data Security & Intelligent Processing Nanjing University of Posts and Telecommunications College of Internet of Things Nanjing University of Posts and Telecommunications School of Computer Science and Engineering Nanjing University of Science and Technology

This paper proposes the concept of inter-cell relay for downlink orthogonal frequency division multiple access(OFDMA) cellular systems, which uses multi-hop to relay calls from overloaded cells to light-load neighboring cells. It is shown that when using inter-cell relay, the number of calls in the congestion cell can be significantly increased. The congestion cell is divided into two parts. One is called non-relay area(NRA), in which a call directly communicates with the base station(BS) of a congested cell. The other is called relay area(RA), in which a call communicates with the BS of a neighboring cell through a relay station(RS). The two parts have different user-call densities. By adjusting the densities of two parts, we will maximize the number of supported calls inside a congested cell. The results show the benefits gained from inter-cell relay in congestion relief, which can reduce cell congestion by fully utilizing the available resources in the neighboring cells.

关键词： OFDMA cellular system congestion relief optimization problem inter-cell relay

Regional Features and Seasonality of Land–Atmosphere Coupling over Eastern China

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2018年第6期35卷 689-701页

作者： Chujie GAO Haishan CHEN Shanlei SUN Bei XU Victor ONGOMA siguang zhu Hedi MA Xing LI Key Laboratory of Meteorological Disaster Ministry of Education (KLME)/International Joint Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)Nanjing University of Information Science and Technology College of Atmospheric Science Nanjing University of Information Science and Technology Department of Meteorology South Eastern Kenya University

Land-atmosphere coupling is a key process of the climate system, and various coupling mechanisms have been proposed before based on observational and numerical analyses. The impact of soil moisture（SM） on evapotranspiration（ET） and further surface temperature（ST） is an important aspect of such coupling. Using ERA-Interim data and CLM4.0 offline simulation results, this study further explores the relationships between SM/ST and ET to better understand the complex nature of the land-atmosphere coupling（i.e., spatial and seasonal variations） in eastern China, a typical monsoon area. It is found that two diagnostics of land-atmosphere coupling（i.e., SM-ET correlation and ST-ET correlation） are highly dependent on the climatology of SM and ST. By combining the SM-ET and ST-ET relationships, two ＂hot spots＂ of land-atmosphere coupling over eastern China are identified： Southwest China and North China. In Southwest China, ST is relatively high throughout the year, but SM is lowest in spring, resulting in a strong coupling in spring. However, in North China, SM is relatively low throughout the year, but ST is highest in summer, which leads to the strongest coupling in summer. Our results emphasize the dependence of land-atmosphere coupling on the seasonal evolution of climatic conditions and have implications for future studies related to land surface feedbacks.

关键词： soil moisture surface temperature land-atmosphere interaction evapotranspiration coupling

基于AHP-DEMATEL的融合创新制度性障碍分析

在线全文

学校读者我要写书评

暂无评论

哈尔滨工程大学学报 2022年第6期43卷 900-906页

作者：李四光马永红朱恩加哈尔滨工程大学经济管理学院黑龙江哈尔滨150001 山东科技大学马克思主义学院山东青岛266590

针对我国融合创新制度存在的问题,本文构建融合创新制度性障碍评价指标体系,通过127份融合创新相关企业问卷数据,运用AHP-DEMATEL法对融合创新制度性障碍进行实证分析。研究发现:保密制度与知识产权制度存在较大的障碍度;重定密轻解密... 详细信息

针对我国融合创新制度存在的问题,本文构建融合创新制度性障碍评价指标体系,通过127份融合创新相关企业问卷数据,运用AHP-DEMATEL法对融合创新制度性障碍进行实证分析。研究发现:保密制度与知识产权制度存在较大的障碍度;重定密轻解密、成果奖励机制缺陷、组织机构设置不健全、定密解密问责力度不大是融合创新的最主要制度性障碍因素;重定密轻解密表现为结果型因素,容易受到其他因素的影响。

关键词： AHP-DEMATEL法融合创新制度障碍指标体系保密制度知识产权制度重定密轻解密成果奖励机制缺陷

Evaluating Common Land Model Energy Fluxes Using FLUXNET Data

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2017年第9期34卷 1035-1046页

作者： Xiangxiang ZHANG Yongjiu DAI Hongzhi CUI Robert E.DICKINSON siguang zhu Nan WEI Binyan YAN Hua YUAN Wei SHANGGUAN Lili WANG Wenting FU College of Global Change and Earth System Science Beijing Normal University School of Atmospheric Sciences Sun Yat-sen University Department of Geological Sciences the University of Texas at Austin

Given the crucial role of land surface processes in global and regional climates, there is a pressing need to test and verify the performance of land surface models via comparisons to observations. In this study, the eddy covariance measurements from 20 FLUXNET sites spanning more than 100 site-years were utilized to evaluate the performance of the Common Land Model （CoLM） over different vegetation types in various climate zones. A decomposition method was employed to separate both the observed and simulated energy fluxes, i.e., the sensible heat flux, latent heat flux, net radiation, and ground heat flux, at three timescales ranging from stepwise （30 rain） to monthly. A comparison between the simulations and observations indicated that CoLM produced satisfactory simulations of all four energy fluxes, although the different indexes did not exhibit consistent results among the different fluxes, A strong agreement between the simulations and observations was found for the seasonal cycles at the 20 sites, whereas CoLM underestimated the latent heat flux at the sites with distinct dry and wet seasons, which might be associated with its weakness in simulating soil water during the dry season. CoLM cannot explicitly simulate the midday depression of leaf gas exchange, which may explain why CoLM also has a maximum diurnal bias at noon in the summer. Of the eight selected vegetation types analyzed, CoLM performs best for evergreen broadleaf forests and worst for croplands and wetlands.

关键词： model evaluation Common Land Model FLUXNET

CT骨性影像学参数于胸腰椎骨折后方韧带复合体损伤诊断中价值及危险因素分析

在线全文

学校读者我要写书评

暂无评论

影像科学与光化学 2021年第4期39卷 589-594页

作者：朱思光孙涛上海宝山区仁和医院/华山医院宝山分院放射科上海200431 江苏省人民医院放射科江苏南京210029

选取380例胸腰椎骨折患者作为研究对象,168例胸腰椎骨折后方韧带复合体(PLC)损伤患者为观察组,212例非PLC损伤患者为对照组。通过统计比较发现,两组的载荷分享评分系统(LCS)评分、胸腰椎损伤分类及严重程度(TLICS)评分、Cobb角度、椎体... 详细信息

选取380例胸腰椎骨折患者作为研究对象,168例胸腰椎骨折后方韧带复合体(PLC)损伤患者为观察组,212例非PLC损伤患者为对照组。通过统计比较发现,两组的载荷分享评分系统(LCS)评分、胸腰椎损伤分类及严重程度(TLICS)评分、Cobb角度、椎体楔变角(SIEA)、局部后凸角(LK)、棘突间距增加值(IISD)相比,差异有统计学意义(P<0.05);CT骨性影像学参数联合诊断胸腰椎骨折PLC损伤的敏感度为72.41%、特异度为87.33%;预后不良患者术前及术后3 d的SIEA、LK、IISD均高于预后良好患者(P<0.05);术后3 d,SIEA、LK、IISD的AUC值均高于术前,且联合预测胸腰椎骨折PLC损伤患者预后的AUC值最高,为0.869。SIEA、LK、IISD为胸腰椎骨折PLC损伤的危险影响因素,三者结合可为临床诊断胸腰椎骨折PLC损伤及预测预后提供参考。

关键词：胸腰椎骨折后方韧带复合体损伤 CT骨性影像学椎体楔变角局部后凸角棘突间距增加值危险因素预后

18氟-氟代脱氧葡萄糖-正电子发射体层显像/计算机体层成像测定密度比在诊断非小细胞肺癌纵隔淋巴结转移中的应用价值

在线全文

学校读者我要写书评

暂无评论

实用临床医药杂志 2019年第1期23卷 18-21,24页

作者：朱思光孙倩上海宝山区仁和医院放射科上海200431 江苏省人民医院放射科江苏南京210029

目的探讨18氟-氟代脱氧葡萄糖(18F-FDG)-正电子发射体层显像(PET)/计算机体层成像(CT)测定密度比在诊断非小细胞肺癌(NSCLC)纵隔淋巴结转移中的应用价值。方法回顾性分析68例NSCLC患者18F-FDG-PET/CT检查结果,测量淋巴结短径、标准化摄... 详细信息

目的探讨18氟-氟代脱氧葡萄糖(18F-FDG)-正电子发射体层显像(PET)/计算机体层成像(CT)测定密度比在诊断非小细胞肺癌(NSCLC)纵隔淋巴结转移中的应用价值。方法回顾性分析68例NSCLC患者18F-FDG-PET/CT检查结果,测量淋巴结短径、标准化摄取值(SUV)、CT密度及纵隔血池CT密度等,计算淋巴结与纵隔血池密度比。以手术和病理学结果为对照,分析PET/CT综合分析法和密度比对NSCLC纵隔淋巴结转移的诊断价值。结果本研究68例NSCLC患者中,共有398枚淋巴结,纵隔淋巴结转移64枚。纵隔淋巴结转移者淋巴结短径、淋巴结SUVmax和病灶SUVmax高于未转移者,转移者淋巴结与纵隔血池密度比低于未转移者,差异有统计学意义(P <0. 01)。ROC曲线分析结果显示,在诊断NSCLC纵隔淋巴结转移的敏感度、特异度、准确度方面,PET/CT综合分析法为78. 13%、80. 24%、79. 90%,淋巴结与纵隔血池密度比以<0. 85为临界值时为75. 00%、76. 95%、76. 63%,二者联合时为93. 75%、86. 23%、87. 44%,二者联合时诊断效能显著高于二者单独时(P <0. 01)。结论 PET/CT综合分析法和密度比均可作为诊断NSCLC纵隔淋巴结转移的有效方法,且二者联合时具有更高的诊断效能。

关键词： 18氟-氟代脱氧葡萄糖正电子发射体层显像计算机体层成像密度比非小细胞肺癌纵隔淋巴结转移诊断

初中学生情绪调控策略与学业自我效能感、学习成绩关系的研究

在线全文

学校读者我要写书评

暂无评论

教育学术月刊 2015年第10期 53-57页

作者：陈四光余仙平朱荣安献丽扬州大学教育科学学院江西中医药大学

通过随机抽样的方法对来自江苏一所中学的228名初中生进行问卷调查,采用认知情绪调节问卷和学业自我效能感问卷研究初中生情绪调控策略与学业自我效能感、学习成绩的关系。研究结果表明:学习自我效能感及积极的情绪调控策略均能很好地... 详细信息

通过随机抽样的方法对来自江苏一所中学的228名初中生进行问卷调查,采用认知情绪调节问卷和学业自我效能感问卷研究初中生情绪调控策略与学业自我效能感、学习成绩的关系。研究结果表明:学习自我效能感及积极的情绪调控策略均能很好地预测学生的学习成绩,但消极情绪调控策略与学习成绩之间不存在显著相关。自我责备、接受、沉思、积极关注、重新规划、积极评价等积极情绪调控策略在学业自我效能感和学习成绩之间存在显著的中介效应。

关键词：情绪调控策略学业自我效能感学习成绩初中生