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GEOLOGICAL MARKS OF A POSSIBLE EXTRATERRESTRIAL IMPACT EVENT ON THE BOUNDARY BETWEEN SINIAN/CAMBRIAN IN TIANMENSHAN IN WESTERN HUNAN
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作者 HUANG Huaiyong WANG Daojing CHEN Guanghao YIN Hanhui 《Geotectonica et Metallogenia》 2004年第1期43-52,共10页
Geologic marks related to extraterrestrial impact events, such as impact split gravels, impact brecciate layers, impact dikes, microirghizites, microtektites, especially meteoritic residues, were discovered on the bou... Geologic marks related to extraterrestrial impact events, such as impact split gravels, impact brecciate layers, impact dikes, microirghizites, microtektites, especially meteoritic residues, were discovered on the boundary between Sinian/Cambrian at Tianmenshan of Western Hunan, which may possibly demonstrate that an extraterrestrial impact event has ever occurred there on the S/C boundary. 展开更多
关键词 Tianmenshan the BOUNDARY BETWEEN Sinian/Cambrian microtektite meteoritic FRAGMENT extraterrestrial impact event
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The impact analysis of policy events on China's carbon market
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作者 Bo Chen Chenyu Bian Wei Shen 《Chinese Journal of Population,Resources and Environment》 2018年第4期289-298,共10页
This paper interrogates the impact of policy events on the efficiency of carbon market in China.The analysis covers five piloting emission trading schemes(Beijing, Shanghai, Guangdong,Shenzhen and Hubei), particularly... This paper interrogates the impact of policy events on the efficiency of carbon market in China.The analysis covers five piloting emission trading schemes(Beijing, Shanghai, Guangdong,Shenzhen and Hubei), particularly focusing on Guangdong pilot for its weak form efficiency and the richness of policy events. Twenty-five policy events between 2014 and 2016 are categorized into seven groups. The efficiency test indicates that only Guangdong ETS has reached weak form efficiency. After exploring the policy events occurred in Guangdong ETS, it finds that although a clear long-term climate policy has been set up over the country, China's carbon market still has a conservative risk appetite and its governing institutions still needs further development. The policy makers need to be aware of and avoid the negative impacts of policy events to the market evolvement, by introducing effective consultancy process with the stakeholders and nurturing market expectations in the long run. We also find that events like allowance auctions have considerably less impacts than previously expected and argue that auction approach should be considered a preferable option over a free allocation system in the future policy design. 展开更多
关键词 Carbon MARKET China POLICY impact MARKET efficiency event ANALYSIS
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The Impacts of International Sport Events:Case Studies of Two Hungarian Cities,Gyor and Székesfehérvár
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作者 Tünde Máté 《Economics World》 2018年第5期401-414,共14页
After the period between 1998 and 2002, sport has again and continuously been considered as a priority strategicsector in Hungary since the year 2010. Hungary has demonstrated remarkable performance in organisinginter... After the period between 1998 and 2002, sport has again and continuously been considered as a priority strategicsector in Hungary since the year 2010. Hungary has demonstrated remarkable performance in organisinginternational sport events. The FINA World Championships and the European Youth Olympic Festival, both heldin 2017, as well as the annual GyulaiIstván Memorial Athletics Hungarian Grand Prix have profound worldwidesignificance. The objective of the study is to give an insight into how the two host cities (Gyor and Székesfehérvár)and their residents perceive these international sport events and their impacts in Hungary. 展开更多
关键词 residents perceive international sport events impacts strategic planning urban development
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计及高影响天气事件的风光长期时间序列预测研究现状与关键技术展望
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作者 白婕 秦晓辉 +2 位作者 安鹏 吴涛 侯翔天 《电网技术》 北大核心 2026年第2期829-848,共20页
随着风光并网规模逐步扩大,风光所带来的不确定性给新型电力系统运行带来极大挑战。与此同时,风光受天气影响颇深,近年来频发的高影响天气事件加剧了风光资源的波动性,进一步加剧新型电力系统的不确定性。提高风光时间序列的预测精度是... 随着风光并网规模逐步扩大,风光所带来的不确定性给新型电力系统运行带来极大挑战。与此同时,风光受天气影响颇深,近年来频发的高影响天气事件加剧了风光资源的波动性,进一步加剧新型电力系统的不确定性。提高风光时间序列的预测精度是有效应对不确定性挑战的关键技术。然而,当前研究多注重正常运行情况下风光时间序列的中短期预测,针对高影响天气的风光长期时间序列预测鲜有研究。为弥补这方面的空白,针对新型电力系统中计及高影响天气的风光长期时间序列预测开展系统性分析和综述。首先,分析典型高影响天气事件对新型电力系统的影响及其预测方法;然后,分别从正常情况以及高影响天气情况对风光长期时间序列预测方法进行梳理;其次,对风光长期时间序列预测应用场景进行概述并给出具体的应用示例;最后,对现有研究中存在的研究难点进行了归纳,并对未来的发展前景进行展望,为未来新型电力系统在高影响天气条件下的长期规划及韧性提升提供支撑。 展开更多
关键词 时间序列预测 高影响天气事件 长期时间序列 可再生能源
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重庆市近年典型特大暴雨过程对比分析
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作者 张宏伟 《中国防汛抗旱》 2026年第2期64-69,共6页
重庆市近年来特大暴雨过程发生频繁,由暴雨直接引发的山洪、地质灾害等给各地造成较为严重的损失。通过收集典型案例复盘资料,梳理有关研究成果,并结合近年应对工作实际,对2020—2025年重庆市8场特大暴雨过程的典型性、特征值、成因及... 重庆市近年来特大暴雨过程发生频繁,由暴雨直接引发的山洪、地质灾害等给各地造成较为严重的损失。通过收集典型案例复盘资料,梳理有关研究成果,并结合近年应对工作实际,对2020—2025年重庆市8场特大暴雨过程的典型性、特征值、成因及其灾害影响、典型事件、致灾因素等进行对比分析,归纳特大暴雨过程及暴雨灾害的典型特征与规律,进而提出针对性防控对策与建议,以期为提升防汛救灾工作能力提供参考。 展开更多
关键词 特大暴雨过程 暴雨灾害影响 对比分析 重庆市
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大型体育赛事的成本与收益之争
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作者 刘东锋 《首都体育学院学报》 北大核心 2026年第1期1-12,47,共13页
全面地认识大型体育赛事的收益与成本是提高办赛效益的前提。以奥林匹克运动会为例,运用文献研究法、案例分析法、逻辑分析法等方法分析大型体育赛事的成本与收益,并从体育设施遗产、城市更新等维度分析大型体育赛事对举办地产生的影响... 全面地认识大型体育赛事的收益与成本是提高办赛效益的前提。以奥林匹克运动会为例,运用文献研究法、案例分析法、逻辑分析法等方法分析大型体育赛事的成本与收益,并从体育设施遗产、城市更新等维度分析大型体育赛事对举办地产生的影响,为大型体育赛事的申办与举办提供理论参考。从经济成本分析,举办大型体育赛事需要财政资金投入,赛事的经济效益也并不一定显著。而在体育设施遗产、城市更新、主办地城市形象塑造、心理收入、体育发展等方面,同样是机遇与挑战并存。分析后提出,大型体育赛事申办之前应做好充分的评估,审慎选择赛事再作出是否申办的决定;主办方向赛事所有权机构争取赛事举办成本分摊与收益分配的最大可能的比例;通过遗产战略规划和赛事市场开发策略,提高赛事综合效益,减少各种潜在的不确定性风险。 展开更多
关键词 大型体育赛事 奥林匹克运动会 成本效益 经济影响 遗产
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The Last 15,000 Years: Climate-Controlled and “Rare-Event”-Triggered/Rise and Fall of Holocene Cultures in the Near/Middle East and in Central Europe—Evidence and Background 被引量:2
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作者 Werner Schneider Elias Salameh 《Open Journal of Geology》 2015年第11期743-769,共27页
Pushed by the results of a preceding publication on the possibly Quaternary Jebel Waqf as Suwwan Meteorite Crater, Jordan [5], where an amazing coincidence of Rapid Climate Changes (RCCs) with Rise and Fall of Neolith... Pushed by the results of a preceding publication on the possibly Quaternary Jebel Waqf as Suwwan Meteorite Crater, Jordan [5], where an amazing coincidence of Rapid Climate Changes (RCCs) with Rise and Fall of Neolithic and Bronze Age Cultures became evident for the Near/Middle East, this paper deals with the same subject, however, relating to the complete Holocene period in the same area and, additionally, in Central Europe as well. By application of modern climatic data [6] comprising isotope analysis (δ18O, 14C, 10Be), acid and aerosol events, and greenhouse gases (CO2, CH4) Greenland ice cores as well as other astro-/geophysical and geological parameters, an overwhelming coincidence/relation/interdependence of both natural and cultural evidences becomes obvious throughout the last 15,000 years across the Northern Hemisphere. Apart from solar output and other astrophysical processes, most important climate- and Earth-related parameters are Mega-Volcanism (i.e.Santorini Greece: ~3640 yr cal. B. P.), Impact Events (i.e. during Mesolithic: ~9600 yr cal. B. P), rapid oceanic current change (DO-Events), and Plate Tectonics (possibly Atlantis-Event: ~11,500 yr cal. B.P. = Pleistocene/Holocene boundary). The most essential parameter is a significant temperature change related to more or less restricted latitude realms of the Northern Hemisphere. Thus, glacier advance/retreat controls the mobility of peoples (i.e. Nations' Migration, Teutonic Empires) and the access to ore deposits (Au, Ag, Cu, Sn, Zn, Pb, Fe) located in Alpine Mountain Ranges (i.e. End-Neolithic, Early Bronze Age). Myths like the Gilgamesh Epos and John Apocalypse convincingly reveal realistic contents relating to natural hazards like tsunamis, impact and flooding events. They unmisunderstandably make obvious that Myths may provide valuable contributions, especially to Geosciences. Some of the controlling parameters interrelate with others or present a kind of hierarchy: Mega-Volcanism/impact events à ejecta à wildfires, heat storms à cosmic winter, sint winter à stop of photosynthesis à mass extinction environmental pollution à greenhouse effects. Significant events (21 cases in total) occurred on i.e. 展开更多
关键词 Climate RARE eventS Mega-Volcanism impact-events Comets Interdependence/Relationship Myths CULTURES HOLOCENE Near/Middle East Central Europe
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Palaeoclimatic Cycles, Global Environmental Changes and New Glacial Periods Induced by the Impact of Extraterrestrial Bodies
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作者 王世杰 欧阳自远 肖志峰 《Chinese Journal Of Geochemistry》 EI CAS 1999年第4期298-304,共7页
In terms of Earth\|Sun geometry, the Milankovitch theory has successfully explained most of the cyclic palaeoclimatic variations during the history of the Earth, especially in the Quaternary. In this paper, the author... In terms of Earth\|Sun geometry, the Milankovitch theory has successfully explained most of the cyclic palaeoclimatic variations during the history of the Earth, especially in the Quaternary. In this paper, the authors suggest that the impact of extraterrestrial bodies on the Earth may be another mechanism to cause palaeoclimatic cycles, global environmental changes and new glacial periods. Based on geological and geochemical records in the boundary layers produced by six huge Cenozoic bolide\|impact events (65, 34, 15, 2.4, 1.1, 0.73 Ma B.P.), including those at 34, 15, 1.1 and 0.73 Ma B.P. which are represented by four famous tektite\|strewn fields, the process and mechanics of palaeoclimatic cycles and global environmental catastrophes induced by extraterrestrial impact are discussed in detail. Impact\|generated dust, soot and aerosol floating in the stratosphere could result in short\|term (<1 year), rapid drop in temperature immediately after impact. Through self\|regulation of the Earth’s climate system, the temperature at the surface slowly went up within 100a and maintained stable for a long time at 250K. If there were no other factors leading to the break\|down of the newly\|established equilibrium, a new glacial period would be initiated. Estimating from the thickness of \{δ\{\}\+\{13\}C\} and \{δ\{\}\+\{18\}O\} anomalies in sediments across the impact boundary layer and deposition rate, the duration of two stages of the palaeoclimate cycle in the form of cold weather—greenhouse effect—normal weather was 10\+4-10\+5a, respectively. The conclusion deduced from the above model is supported by palaeotemperature change recorded by oxygen isotope in sediments across the impact boundary layer. 展开更多
关键词 古气候 地球环境 流星事件 新生代 新冰河时期
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Regional Tourism Resilience under Crisis Impacts:The Cases of Yangtze River Delta and Pearl River Delta
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作者 Yi Liu Liaofan Chen +1 位作者 Fangfei Han Tong Zhang 《Journal of Geographical Research》 2023年第4期11-25,共15页
Since the beginning of the 21st century,various crisis events have occurred frequently,inflicting substantial impacts on the tourism sector,which has garnered considerable scholarly and policy attention.Nevertheless,l... Since the beginning of the 21st century,various crisis events have occurred frequently,inflicting substantial impacts on the tourism sector,which has garnered considerable scholarly and policy attention.Nevertheless,limited research has systematically explored tourism resilience at the urban scale,and there is a paucity of studies comparing regional differences in tourism resilience under distinct crisis scenarios and their underlying causes.Thus,this study focuses on the Yangtze River Delta and the Pearl River Delta,employing Martin’s regional economic resilience measurement method.It assesses the tourism resilience of the two regions under the impact of the 2008 financial crisis and the COVID-19 pandemic,subsequently visualizing the data results using ArcGIS software.The study also endeavors to unveil potential causes for disparities in urban tourism resilience.The main conclusions are as follows:Firstly,regions with higher economic development exhibit relatively weaker tourism resilience during economic crises,yet demonstrate comparatively stronger resilience during public crises.Secondly,distinct differentiations exist both between and within the Yangtze River Delta and the Pearl River Delta,primarily stemming from variations such as geographical positioning,tourism resource endowments,and industrial and economic structures,both regionally and within individual cities.Thirdly,the determination of regional tourism resilience is intricate and cannot be restricted to a single dimension;multidimensional indicators better encapsulate the essence of regional tourism resilience. 展开更多
关键词 Tourism resilience Financial crisis COVID-19 impact of crisis events Spatial differences
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Investigation on flood event variations at space and time scales in the Huaihe River Basin of China using flood behavior classification 被引量:8
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作者 ZHANG Yongyong CHEN Qiutan XIA Jun 《Journal of Geographical Sciences》 SCIE CSCD 2020年第12期2053-2075,共23页
Flood is one of the severest natural disasters in the world and has caused enormous causalities and property losses.Previous studies usually focus on flood magnitude and occurrence time at event scale,which are insuff... Flood is one of the severest natural disasters in the world and has caused enormous causalities and property losses.Previous studies usually focus on flood magnitude and occurrence time at event scale,which are insufficient to contain entire behavior characteristics of flood events.In our study,nine behavior metrics in five categories(e.g.,magnitude,duration,timing,rates of changes and variability)are adopted to fully describe a flood event.Regional and interannual variations of representative flood classes are investigated based on behavior similarity classification of numerous events.Contributions of geography,land use,hydrometeorology and human regulation on these variations are explored by rank analysis method.Results show that:five representative classes are identified,namely,conventional events(Class 1,61.7% of the total),low discharge events with multiple peaks(Class 2,5.3%),low discharge events with low rates of changes(Class 3,18.1%),low discharge events with high rates of changes(Class 4,10.8%)and high discharge events with long durations(Class 5,4.1%).Classes 1 and 3 are the major flood events and distributed across the whole region.Class 4 is mainly distributed in river sources,while Classes 2 and 5 are in the middle and down streams.Moreover,the flood class is most diverse in normal precipitation years(2006,2008-2010 and 2015),followed by wet years(2007,2013-2014),and dry years(2011 and 2012).All the impact factor categories explain 34.0%-84.1% of individual flood class variations.The hydrometeorological category(7.2%-56.9%)is the most important,followed by geographical(1.0%-6.3%),regulation(1.7%-5.1%)and land use(0.9%-2.2%)categories.This study could provide new insights into flood event variations in a comprehensive manner,and provide decision-making basis for flood control and resource utilization at basin scale. 展开更多
关键词 flood events behavior metrics CLASSIFICATION regional and interannual variations potential impacts
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阿勒泰阿克布拉克(Akebulake)铁陨石撞击熔融花岗岩的冲击变质特征研究
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作者 缪秉魁 王茜 夏志鹏 《矿物学报》 北大核心 2025年第6期1212-1231,共20页
阿克布拉克(Akebulake)铁陨石重达18 t,是中国新疆阿勒泰铁陨石雨中第二大的铁陨石单体。在回收过程中,陨石下方发现了一些玻璃质冲击岩,在随后野外调查中还发现了一块冲击引起的部分熔融花岗岩。然而,由于高山冰川雪山对花岗岩体的风... 阿克布拉克(Akebulake)铁陨石重达18 t,是中国新疆阿勒泰铁陨石雨中第二大的铁陨石单体。在回收过程中,陨石下方发现了一些玻璃质冲击岩,在随后野外调查中还发现了一块冲击引起的部分熔融花岗岩。然而,由于高山冰川雪山对花岗岩体的风化和破坏,该陨石四周没有发现典型的撞击坑构造。因此,本文仅介绍样品的显微结构和冲击变质效应,然后,进一步讨论和确认阿克布拉克铁陨石撞击事件及其冲击条件。基于光学显微镜、电子显微镜和电子探针分析的岩石学观察,阿克布拉克铁陨石的冲击岩经历了严重的冲击变质作用,其冲击变质特征、阶段和效应如下:1)通过丰富的冲击变质现象,确认了阿克布拉克铁陨石造成了强烈的冲击事件;2)阿克布拉克铁陨石的目标岩石靶岩是黑云母花岗岩,其冲击岩的冲击阶段发生了瞬时变化,从F-S5到F-S7;3)玻璃质冲击岩是一种完全熔化的流动玻璃,其冲击阶段为F-S7,而部分熔融花岗岩(ALT-01)两端的冲击程度不同,表现出从F-S5(冲击花岗岩)到F-S6(部分熔融花岗岩)的压力逐渐过渡;4)在阿克布拉克铁陨石的冲击下,矿物显示出不同的冲击诱导变质反应,其中长石更容易被压碎,而石英更难熔融;5)石英表现出不均匀的冲击变质作用,即石英斑晶显示出马赛克裂纹并在颗粒边界处熔化,而在内部裂纹处形成压碎玻璃。根据冲击实验校准和地球陨石坑的自然冲击变质作用,阿克布拉克的冲击效应表明最大峰值压力约为60 GPa,冲击后峰值温度约为1700℃。因此,18 t的阿克布拉克铁陨石直接击中花岗岩目标岩石,很好地记录了冲击条件信息,是一个理想的天然撞击实验。 展开更多
关键词 阿勒泰阿克布拉克铁陨石 冲击变质 撞击作用 花岗岩 陨石坑
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Risk Assessment of Extreme Events along a River Flow
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作者 Ivan K. Diadovski Maya P. Atanassova Vasil Simeonov 《Journal of Water Resource and Protection》 2010年第5期455-461,共7页
The present work considers the Struma River water flow on Bulgarian territory as a starting point for evalua-tion of maximum and minimum water flow using an original integral method. The risk assessment is deter-mined... The present work considers the Struma River water flow on Bulgarian territory as a starting point for evalua-tion of maximum and minimum water flow using an original integral method. The risk assessment is deter-mined by specific indices like the index Mmax,i for the deviation of the maximum water flow from the calcu-lated norm of the maximum flow Qmax,0 and the index Mmin,i for the deviation of the minimum water flow from calculated norm of the minimum flow Qmin,0. The new integral approach introducing specific indicators for risk assessment like the indices Mmin,i and Mmax,i has been checked at three sampling locations of the Na-tional monitoring net along the Struma River: Pernik (in the beginning), Krupnik (in the middle) and Marino pole (at the border in Greece) for the period 1948-2006. A significant trend towards decreasing of Mmax,i in-dex is outlined for the three points. On contrary, a significant trend towards increasing of Mmin,i index is found at Krupnik and Marno pole sampling points. 展开更多
关键词 INTEGRAL Indices CLIMATE impact Water Quality River Flow EXTREME eventS
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Effects on Sedimentary Processes via Upper Triassic Climate Forcing Caused by Multiple Impacting and Large Igneous Provinces (LIP)-Rifting/Degassing: Jordanian Platform/Arabian Plate and Germanic Basin/Central Europe
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作者 Werner Schneider Elias Salameh 《Open Journal of Geology》 CAS 2023年第2期136-170,共35页
Upper Triassic sedimentary systems of both the Arabian Plate and the Germanic Basin reveal climate- and plate tectonic-forced effects through certain time-intervals experienced by architectural elements, lithofacies t... Upper Triassic sedimentary systems of both the Arabian Plate and the Germanic Basin reveal climate- and plate tectonic-forced effects through certain time-intervals experienced by architectural elements, lithofacies types, unconformities, flash flood deposits, maximum flooding surfaces/sequence boundary (MFS/SB), mineralogy, and isotope anomalies. Further, Moon recession and changes of Earth’s rotation velocity (core/mantle boundary) are associated with multiple impacting and large igneous provinces/Mid Oceanic Ridge Basalt, LIP/MORB-rifting/degassing. While acidification (by degassing, sturz-rain) does influence tectosilicates and carbonates, montmorillonite represents a key mineral as transformation of volcanic/impact glass (Tephra) to be found as co-components in and in certain pelite units as “boundary clay-suspicions” (mixture of eolian paleoloess, pelite, paleosol, and tephra → tuffite). Obviously, unconformities and sequence boundaries of both study areas separate and dislocate interrupted ∂<sup>13</sup>C and <sup>87</sup>Sr/<sup>86</sup>Sr-data groups along the isotope curves. Both Proto-Arctic Ocean rifting/degassing comprising kimberlitic pyroclastic eruptions and Neotethys rifting/degassing as well as multiple impacting played the most important role during the Norian, followed by the incipient Central Atlantic Magmatic Provinces rifting since the Rhaetian. The following associations are encountered and dealt with in this study: Sequence boundaries-∂<sup>13</sup>C, maximum flooding surfaces-(FUCs)-∂<sup>13</sup>C, unconformities-plate motion, tephra-pelite-tuffite-montmorillonite. Norian: maximum flooding surfaces (MFSs)-“paleosol”/boundary clay?-rifting-volcanism, Moon/Earth data change. So the Norian (~221 - 206 Ma) hosts anomalous “amalgamated maximum flooding surfaces (MFSs)”, amalgamated paleosol (Jordanian Platform), multiple impacting (~219 - 214 Ma), the maximum opening of the Proto-Arctic Ocean (PAO) (~230 - 200 Ma), Neo-Tethys (NT)-subvolcanic (sills, dikes) in the NE Dead Sea area prior the Rhaetian, and a significant change of Earth/Moon relation data. The study concludes that rare and extreme events are very strongly shaping the geologic constellations in the Earth System. 展开更多
关键词 Endogenic and impact Drivers Sedimentary Effects Interplay Processing event-Stratigraphy
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创伤性骨折患者创伤后成长特点与事件冲击、自我效能感相关性研究
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作者 张莉 王辉 +2 位作者 金明霞 彭灵智 周禹君 《中国医药科学》 2025年第12期96-99,共4页
目的了解创伤性骨折患者创伤后成长(PTG)特点,分析PTG特点与事件冲击、自我效能感的相关性。方法选择2018年1—12月在甘肃省人民医院骨科住院的177例创伤性骨折患者进行问卷调查,分析创伤性骨折患者PTG特点及与事件冲击、自我效能感的... 目的了解创伤性骨折患者创伤后成长(PTG)特点,分析PTG特点与事件冲击、自我效能感的相关性。方法选择2018年1—12月在甘肃省人民医院骨科住院的177例创伤性骨折患者进行问卷调查,分析创伤性骨折患者PTG特点及与事件冲击、自我效能感的相关性。结果创伤性骨折患者PTGI总分为(54.49±22.38)分,处于中等水平;PTG得分与一般自我效能呈正相关,与事件冲击得分呈负相关。结论护理人员应在心理医生的指导下,应用现有量表对创伤性骨折患者早期开展动态评估与干预工作,重点关注创伤性事件的冲击程度以及自我效能情况,以提高患者PTG水平。 展开更多
关键词 创伤性骨折 创伤后成长 事件冲击 自我效能感
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EI Niño对黄河流域次年5~9月降水的影响分析
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作者 刘和远 赵世斗 +1 位作者 陈涛 赵云天 《水电能源科学》 北大核心 2025年第5期25-28,共4页
基于1961~2020年黄河流域5~9月降水数据,利用EOF经验正交函数分析了1980年前后EI Niño发生次年黄河流域的降水差异,并对降水差异对应的大气环流差异进行对比。结果表明,1980年前后,El Niño发生次年黄河流域5~9月降水主模态发... 基于1961~2020年黄河流域5~9月降水数据,利用EOF经验正交函数分析了1980年前后EI Niño发生次年黄河流域的降水差异,并对降水差异对应的大气环流差异进行对比。结果表明,1980年前后,El Niño发生次年黄河流域5~9月降水主模态发生了显著变化,地区分布上显著差异区位于兰州以上的黄河源头和黄河下游地区。时间演变上,1980年后黄河上游降水较之前异常偏多,下游降水较之前异常偏少。500 hPa场上,1980年前中纬度西风带我国大陆表现为异常东高西低形势场分布,水汽在黄河下游呈辐合形势,1980年后表现为西太平洋副高异常偏强偏北,黄河上游为水汽辐合区。 展开更多
关键词 EI Niño事件 降水差异 黄河流域 影响分析
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灾变风险动态演化下量子-经典混合驱动的电力系统弹性评估方法 被引量:2
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作者 付炜 谢海鹏 +2 位作者 辛宇 陈晨 别朝红 《中国电机工程学报》 北大核心 2025年第15期5771-5783,I0004,共14页
极端灾害风险动态演化下,新型电力系统弹性评估面临高维场景生成及遍历分析效率低、小概率-高损失事件风险量化精度不足等挑战,而量子计算并行计算处理能力强、潜力巨大,有望突破经典计算瓶颈。该文提出量子-经典混合驱动的电力系统弹... 极端灾害风险动态演化下,新型电力系统弹性评估面临高维场景生成及遍历分析效率低、小概率-高损失事件风险量化精度不足等挑战,而量子计算并行计算处理能力强、潜力巨大,有望突破经典计算瓶颈。该文提出量子-经典混合驱动的电力系统弹性评估方法,构建融合风险动态更新与量子计算的弹性评估框架。首先,构建台风预警信息动态更新下线路故障概率的量子计算模型,利用量子叠加态生成风速场景,并行化估计潜在风险分布下的故障概率,克服经典方法场景遍历计算效率低的困难;进而,设计量子线路驱动的弹性评估模型与架构,对条件风险价值等刻画尾部风险指标实现二次收敛加速计算,解决厚尾分布下风险高效量化难题;然后,提出量子-经典混合弹性评估流程,结合量子电路优化与蒙特卡洛灾损模拟,实现系统损失风险的短时滚动快速评估和全过程模拟评估。最后,基于IBM Qiskit量子模拟器,利用IEEE 33节点系统验证所提方法有效性。 展开更多
关键词 量子计算 弹性评估 量子振幅估计 条件风险价值 小概率-高损失事件
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台风灾害影响的产业链跨部门传导机制——以台风“天鸽”为例 被引量:2
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作者 林舒婷 夏琳琳 +1 位作者 王晓明 梁赛 《灾害学》 北大核心 2025年第1期213-219,共7页
极端天气事件会通过产业链对经济系统产生级联影响,现有研究聚焦极端天气事件影响评估,但仍未明晰极端天气事件影响在经济系统产业链的跨部门传导机制。该文通过整合自适应区域投入产出模型、结构路径分析和介数中心性分析方法,以台风... 极端天气事件会通过产业链对经济系统产生级联影响,现有研究聚焦极端天气事件影响评估,但仍未明晰极端天气事件影响在经济系统产业链的跨部门传导机制。该文通过整合自适应区域投入产出模型、结构路径分析和介数中心性分析方法,以台风“天鸽”为例,揭示了台风灾害影响对广东省产业链的跨部门传导机制。研究发现,台风“天鸽”造成广东省经济损失共310亿元,其中间接损失占13%。在台风灾害发生阶段,造成经济损失的关键传导路径与建筑业紧密相关,如非金属矿物制品业→建筑业;关键传输部门包括通信设备、计算机和其他电子设备制造业,金属冶炼和压延加工业等;典型的关键部门间关联包括金属冶炼和压延加工业→建筑业等。在重建阶段,金属矿采选业、金融业、房地产业等部门从重建需求中获得较多经济收益。研究为提高产业链适应能力和灾后资金分配提供决策支持。 展开更多
关键词 极端天气事件 台风 经济影响 投入产出分析 产业链
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面向台风灾害影响预报的知识集成框架 被引量:1
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作者 叶鹏 张雪英 《自然灾害学报》 北大核心 2025年第3期34-47,共14页
台风灾害影响预报是以灾害后果为重点、以公众感受为牵引的一种新型台风灾害预报方式。台风灾害影响的领域众多,还具有高度动态性,使得影响预报所需的领域知识来源分散且不断变化。“人-物-网”全方位的灾害大数据能够探测到台风灾害过... 台风灾害影响预报是以灾害后果为重点、以公众感受为牵引的一种新型台风灾害预报方式。台风灾害影响的领域众多,还具有高度动态性,使得影响预报所需的领域知识来源分散且不断变化。“人-物-网”全方位的灾害大数据能够探测到台风灾害过程变化,而灾害机理中蕴含了影响预报所需的丰富领域知识,亟需通过知识集成实现二者优势的深度耦合。因此,文中将机理和过程作为台风灾害影响预报的理论基础和关键线索,构建基于机理的台风灾害影响预报知识体系,研究基于状态的台风灾害过程识别方法,提出过程引导的台风灾害影响预报知识聚合方法。文中方法不仅提升了台风灾害影响预报中知识服务的针对性,也增强了台风灾害影响预报结果的可解释性,有利于推动防灾减灾知识服务的情境化与智能化。 展开更多
关键词 台风灾害 影响预报 灾害机理 事件过程 知识集成 台风“贝碧嘉”
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肾移植术后患者创伤后应激症状与脑灰质体积减小的相关性研究:基于体素形态学测量方法
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作者 王昕怡 朱昕怡 +5 位作者 穆俊娅 欧阳远朔 王雨晨 关楚欣 麻少辉 张明 《西安交通大学学报(医学版)》 北大核心 2025年第5期860-864,共5页
目的探讨肾移植术后患者(KTRs)脑灰质体积的变化及其与KTRs创伤后应激症状(PTSS)的相关性,以期为早期识别和干预KTRs的PTSS提供神经影像学依据。方法46名KTR患者和年龄、性别、教育水平匹配的46名健康对照(HCs)均接受了颅脑MRI 3D-T1加... 目的探讨肾移植术后患者(KTRs)脑灰质体积的变化及其与KTRs创伤后应激症状(PTSS)的相关性,以期为早期识别和干预KTRs的PTSS提供神经影像学依据。方法46名KTR患者和年龄、性别、教育水平匹配的46名健康对照(HCs)均接受了颅脑MRI 3D-T1加权结构像扫描,并应用基于体素的形态学测量(VBM)方法,比较两组间脑灰质体积的差异,进一步对KTRs与HCs之间存在差异的脑区灰质体积与用于评估PTSS的严重程度的修订版事件影响量表(IES-R)评分进行相关性分析。结果与HCs组相比,KTRs组患者双侧中央前回、额中回、补充运动区、内侧旁扣带回及双侧颞中回的灰质体积显著减小,差异均有统计学意义(P<0.05,TFCE-FWE校正)。KTRs的左侧额中回灰质体积与其IES-R量表评分呈负相关(r=-0.235,P=0.022)。结论KTRs存在脑灰质体积的异常,且其左侧额中回灰质体积与PTSS相关。 展开更多
关键词 肾移植 创伤后应激症状 脑灰质体积 事件影响量表(IES) 磁共振成像
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以品牌学术活动促进理工类高校学报影响力提升的实践与思考——以《上海交通大学学报》“作者沙龙”为例
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作者 王历历 李博文 蒋霞 《编辑学报》 北大核心 2025年第3期296-300,共5页
打造品牌学术活动是促进理工类高校学报影响力提升的有利措施之一。本文总结了《上海交通大学学报》举办“作者沙龙”系列学术活动的实践经验,指出该活动架构特色体现在管理运作中人员分工明确、活动内容策划主次分明、活动宣传与实施... 打造品牌学术活动是促进理工类高校学报影响力提升的有利措施之一。本文总结了《上海交通大学学报》举办“作者沙龙”系列学术活动的实践经验,指出该活动架构特色体现在管理运作中人员分工明确、活动内容策划主次分明、活动宣传与实施得到“平台+策略”配套保障,并证实该活动的举办促使本刊新媒体平台关注度稳步攀升、相关论文使用数据提升、相应专栏稿源增加。研究揭示了本刊作为高校学报,成功利用品牌学术活动扩大知名度并增强影响力的核心要素,包括内容策划突出专业特色、服务对象以青年学者为先、重视“平台+策略”的宣发体系构建,为期望通过举办学术活动提升影响力的高校学报提供有益参考。 展开更多
关键词 科技期刊 高校学报 学术活动 期刊品牌 影响力
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