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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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台风灾害影响的产业链跨部门传导机制——以台风“天鸽”为例
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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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突发公共卫生事件下投资者情绪对股票市场的影响研究
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作者 于慧佳 《江苏商论》 2025年第1期77-82,共6页
2019年12月底,由美国暴发的新冠疫情传入中国,疫情对全球、全国的经济造成了显著影响,全球股市也进入寒冬。股市是经济的晴雨表,在中国的股票市场中,有超过九成的投资者属于个人投资者,个人投资者的情绪反映与股票市场的涨跌息息相关。... 2019年12月底,由美国暴发的新冠疫情传入中国,疫情对全球、全国的经济造成了显著影响,全球股市也进入寒冬。股市是经济的晴雨表,在中国的股票市场中,有超过九成的投资者属于个人投资者,个人投资者的情绪反映与股票市场的涨跌息息相关。基于此,论文选取换手率、成交量、腾落比例、融资融券余额和百度搜索指数这5个单项指标通过主成分分析法建立投资者情绪综合指标。同时选取相关指标构建疫情综合指标,并通过VAR模型、Granger因果检验、脉冲响应分析、方差分解等方法考察二者与股票收益率之间的关系,同时,提出建议。 展开更多
关键词 冲击事件 投资者情绪 主成分分析 VAR 脉冲响应
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基于P6进度延误分析的工期索赔方法研究及应用
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作者 高琰哲 黄雁飞 《中国港湾建设》 2025年第2期98-102,共5页
科学的工期管理能够保障业主按期投产运营,产生良好的经济效益和社会效益。由于国际工程项目涉及外部环境复杂,技术重难点多,管理协调难度大,在实际实施过程中往往存在工期延误。为探明工期索赔计算方法,本研究基于Primavera 6软件,通... 科学的工期管理能够保障业主按期投产运营,产生良好的经济效益和社会效益。由于国际工程项目涉及外部环境复杂,技术重难点多,管理协调难度大,在实际实施过程中往往存在工期延误。为探明工期索赔计算方法,本研究基于Primavera 6软件,通过“影响事件插入+计划与实际对比”延误分析方法,并依托阿尔及利亚某油气港口改扩建项目进行工期索赔方法研究及应用。结果表明,采取决策矩阵的方式选用延误分析方法;同时采用“影响事件插入+计划与实际对比法”进行P6进度延误分析,可有力支撑工期索赔。该研究内容为解决关键路线上的进度延误,避免不必要的赶工,合理高效地组织后续施工提供了参考。 展开更多
关键词 工期索赔 Primavera 6 项目延误分析 影响事件插入
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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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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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基于儿童认知心理的盐业历史博物馆体验设计研究
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作者 张玉萍 丁亚玲 《创意设计源》 2024年第5期74-79,共6页
自贡市盐业历史博物馆是集教育、审美和互动为一体的公共文化场所,是儿童接收井盐文化教育的关键途径。基于儿童认知心理和体验EEI模型,梳理儿童认知下的体验设计框架,并结合盐业历史博物馆体验现状,归纳运算阶段儿童的体验形式,并同时... 自贡市盐业历史博物馆是集教育、审美和互动为一体的公共文化场所,是儿童接收井盐文化教育的关键途径。基于儿童认知心理和体验EEI模型,梳理儿童认知下的体验设计框架,并结合盐业历史博物馆体验现状,归纳运算阶段儿童的体验形式,并同时辅助非结构式访谈和用户旅程图,提炼儿童认知下的盐业历史博物馆体验需求和体验痛点。最后,从感知、思维、记忆三个认知层次出发,提出面向儿童的盐业博物馆体验设计策略,旨在提升其教育功能,促进运算阶段儿童深化对井盐文化的感知与理解,全面深化井盐文化的体验。 展开更多
关键词 儿童认知心理 体验EEI模型 盐业历史博物馆
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拦截机动目标的固定时间事件触发协同制导律
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作者 王鹏 何智川 +3 位作者 李军智 李虹言 耿宝魁 范卫鹏 《北京理工大学学报》 EI CAS CSCD 北大核心 2024年第10期1040-1050,共11页
针对无向通信拓扑结构下的多枚导弹考虑角度约束同时攻击机动目标的问题,提出一种事件触发控制下的固定时间收敛分布式多弹协同制导律.首先,建立导弹-目标相对运动学模型,在视线坐标系下解耦为沿视线和垂直视线两个方向.其次,在视线切... 针对无向通信拓扑结构下的多枚导弹考虑角度约束同时攻击机动目标的问题,提出一种事件触发控制下的固定时间收敛分布式多弹协同制导律.首先,建立导弹-目标相对运动学模型,在视线坐标系下解耦为沿视线和垂直视线两个方向.其次,在视线切向考虑时间约束,提出一种基于事件触发机制的固定时间收敛协同制导律,保证攻击时间的一致性;在视线法向上考虑空间角度约束,提出一种基于固定时间收敛理论的分布式空间协同制导律,使视线角和视线角速率快速收敛到期望值,以满足脱靶量和终端角度约束;同时,针对目标机动引起的系统扰动,采用固定时间收敛的观测器进行在线估计与补偿.利用Lyapunov理论,证明了所提出协同制导律的稳定性.最后,通过数学仿真,验证了所提出的协同制导律的有效性. 展开更多
关键词 协同制导 事件触发控制 固定时间收敛 攻击时间及攻击角度约束 机动目标
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伦理敏感性在护理大专实习生死亡应对自我效能与心理压力间的中介效应
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作者 李鹏 张源慧 +4 位作者 唐龙 陈雪蕾 刘杉 郑晓妮 王武江 《护理管理杂志》 CSCD 2024年第11期973-978,共6页
目的探讨伦理敏感性在护理大专实习生死亡应对自我效能与心理压力间的中介效应。方法采用便利抽样法,于2023年7月至8月选取长沙市、益阳市和桂林市共6所三级甲等医院的216名全日制护理大专实习生作为研究对象。采用一般资料问卷、死亡... 目的探讨伦理敏感性在护理大专实习生死亡应对自我效能与心理压力间的中介效应。方法采用便利抽样法,于2023年7月至8月选取长沙市、益阳市和桂林市共6所三级甲等医院的216名全日制护理大专实习生作为研究对象。采用一般资料问卷、死亡应对自我效能量表、护理学生伦理敏感性问卷、事件影响量表进行调查。结果护理大专实习生的死亡应对自我效能、伦理敏感性、心理压力得分分别为(90.83±17.14)分、(39.54±5.99)分、(29.81±13.04)分;心理压力与死亡应对自我效能、伦理敏感性均呈负相关(r_(1)=-0.221,r_(2)=-0.442;P<0.01),死亡应对自我效能与伦理敏感性呈正相关(r=0.288,P<0.01);伦理敏感性在其死亡应对自我效能与心理压力间发挥完全中介效应,效应值为-1.099,占总效应的99.46%。结论护理大专实习生普遍存在心理压力,伦理敏感性在其死亡应对自我效能与心理压力间发挥完全中介效应。学校教育和临床教学中应注意多维度干预提升护理学生的伦理敏感性,以提高其死亡应对自我效能,降低心理压力。 展开更多
关键词 护理实习学生 心理压力 事件影响 伦理敏感性 死亡应对自我效能 中介效应
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综合交通运输服务指数构建与应用研究 被引量:3
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作者 李蓁 段雅馨 +3 位作者 成宇飞 赵剑楠 马宁远 孙璐 《铁道运输与经济》 北大核心 2024年第3期198-206,共9页
交通运输作为国民经济和社会发展的“先行官”,是经济社会发展的重要标志。而综合交通运输体系发展是当代交通运输发展的新趋势、新方向。为健全和完善综合交通运输体系,提出构建综合交通运输服务指数方法,并以陕西省为例,选取铁路、公... 交通运输作为国民经济和社会发展的“先行官”,是经济社会发展的重要标志。而综合交通运输体系发展是当代交通运输发展的新趋势、新方向。为健全和完善综合交通运输体系,提出构建综合交通运输服务指数方法,并以陕西省为例,选取铁路、公路、水运、航空、邮政五大运输领域运量数据,通过对缺失值补充、季节调整、无量纲化、熵权法确定权重,进而使用Fisher-ideal方法构建陕西省综合交通运输服务指数,并结合HP滤波处理的周期性分析、重大事件影响分析验证其合理性。结果表明:构建的综合交通运输服务指数能在一定程度上发挥宏观经济的先行指标功能,可展现不同阶段重大事件对交通运输业的影响,具有适用性。 展开更多
关键词 综合交通运输服务指数 熵权法 Fisher-ideal方法 周期性分析 重大事件影响分析
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考虑交通事件影响的高速公路短时行程时间预测
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作者 潘杰 石京 《交通工程》 2024年第8期45-53,74,共10页
本研究目的是基于历史行程数据并考虑交通事件,构建可提高高速公路短时行程时间预测精度的方法。基于深层机器学习理论,设计加权均方根相似(Weighted-RMSS)模型,利用经纬度将行程分段,考虑高速公路车辆时空流动性的时间传递,计算当前行... 本研究目的是基于历史行程数据并考虑交通事件,构建可提高高速公路短时行程时间预测精度的方法。基于深层机器学习理论,设计加权均方根相似(Weighted-RMSS)模型,利用经纬度将行程分段,考虑高速公路车辆时空流动性的时间传递,计算当前行程时间和历史案例行程时间的相似性,提高了行程时间预测精确度。在此基础上,结合交通事件数据建立交通事件影响矩阵,建立LGBM模型(Light Gradient Boosting Machine)用于短时行程时间预测,并利用广州高速公路平沙至机场南路段实测数据进行验证。研究结果表明,开发2个模型效果均优于传统KNN模型,且考虑了交通事件影响的LGBM模型的预测精度高于Weighted-RMSS模型,达到95.68%,比较不同未来预测时间得出预测5 min效果最佳,精度可达96.18%。本研究在短时行程时间预测上有显著的优越性,有助于为驾驶人提供准确的出行时间,有利于高速公路的交通管理。 展开更多
关键词 高速公路 行程时间预测 时空流动性 加权均方根相似模型 交通事件影响 LGBM模型
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气候变化对园艺作物生产的影响 被引量:1
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作者 杨飞雪 《农机使用与维修》 2024年第6期133-135,共3页
近年来随着极端天气事件频率和强度的增加,对园艺作物的生长、产量和品质都造成了不同程度的影响。该文通过综述和分析文献资料,基于气候变化中气温升高、降水变化、极端天气事件增加等情况,探讨相关因素对园艺作物的生长发育和产量稳... 近年来随着极端天气事件频率和强度的增加,对园艺作物的生长、产量和品质都造成了不同程度的影响。该文通过综述和分析文献资料,基于气候变化中气温升高、降水变化、极端天气事件增加等情况,探讨相关因素对园艺作物的生长发育和产量稳定性的影响,以及气候变化对园艺作物生长环境中土壤水分、温度、光照等因素的变化对不同作物的适应性和产量的影响及当前研究的不足,总结应对气候变化的关键策略并提出未来研究的方向,如优化种植结构、调整栽培措施、采用抗逆性强的品种、改善耕作管理等措施,以提高园艺作物对气候变化的适应能力和生产稳定性,并不断开发更加适应性强的新品种、建立全面有效的气候调控技术体系等,通过综合利用技术手段和管理措施,可以有效减轻极端天气对园艺作物生产的影响,保障农业生产的稳定性和可持续发展。 展开更多
关键词 极端天气事件 园艺作物生产 影响 应对策略 抗逆性品种
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高校大面积停电事件情景构建及应急处置
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作者 付春岚 成连华 +3 位作者 邓伟杰 马翠英 郭慧敏 曹东强 《西安科技大学学报》 CAS 北大核心 2024年第4期680-687,共8页
高校作为一个独特的社区,对大面积停电事件的敏感性较高。此类事件不仅影响教学和生活,还可能威胁到高校的安全稳定。为全面探究大面积停电事件对高校安全稳定的影响及应急处置策略,首先通过分析近年来国内外高校大面积停电事件,归纳出... 高校作为一个独特的社区,对大面积停电事件的敏感性较高。此类事件不仅影响教学和生活,还可能威胁到高校的安全稳定。为全面探究大面积停电事件对高校安全稳定的影响及应急处置策略,首先通过分析近年来国内外高校大面积停电事件,归纳出人为、技术和设备、系统设计、自然环境等影响因素,从电网、基础设施、服务保障、社会影响4个层面建立影响模型,分析了高校电力系统的整体性及脆弱性;然后结合霍尔三维结构理论,从风险演化、事件分类、应急响应3个维度构建了高校大面积停电事件情景构建分析模型,对高校大面积停电重点关注事件、情景处置和应急任务进行分类、分层阐释;最后基于西安某高校停电事件,对情景构建分析模型和应急任务的可行性进行了验证。结果表明:列出的不同时段重点关注事件有助于识别高校大面积停电事件突发应对关键脆弱点,建立的情景构建分析模型和应急任务是可行的。研究结果能为高校有效应对大面积停电事件、保障校园安全稳定提供参考。 展开更多
关键词 大面积停电事件 情景构建 应急管理 电力系统影响 应急处置
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高校体育赛事对学生体育参与度的影响分析
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作者 杨璇 《当代体育科技》 2024年第9期159-162,共4页
该研究旨在研究高校体育赛事对学生体育参与度的影响,并就此提出合理的解决方案。正面影响方面,体育赛事能够促进学生身体健康、培养运动习惯、加强团队协作和领导能力,同时提高社交能力。然而,负面影响涉及学业压力、时间管理、竞争压... 该研究旨在研究高校体育赛事对学生体育参与度的影响,并就此提出合理的解决方案。正面影响方面,体育赛事能够促进学生身体健康、培养运动习惯、加强团队协作和领导能力,同时提高社交能力。然而,负面影响涉及学业压力、时间管理、竞争压力和心理健康问题。解决方案包括合理安排赛事时间、提供学业与体育平衡培训、强调心理健康支持,并持续评估与改进整合系统,以促进学生的全面发展。 展开更多
关键词 高校 体育赛事 学生体育参与度 影响分析
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青藏高原隆升动力学与阿尔金断裂 被引量:71
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作者 葛肖虹 刘永江 任收麦 《中国地质》 CAS CSCD 2002年第4期346-350,共5页
青藏高原最晚一期也是最强烈的一期隆升发生在1~0.8Ma,与印度洋中脊三联点附近的“亚澳”陨击事件有关。陨击事件引起印度洋的快速扩张并导致印度板块在锡瓦利克带的强烈(A型)俯冲,正是这次俯冲引起了青藏高原及其外围山脉的快速隆升,... 青藏高原最晚一期也是最强烈的一期隆升发生在1~0.8Ma,与印度洋中脊三联点附近的“亚澳”陨击事件有关。陨击事件引起印度洋的快速扩张并导致印度板块在锡瓦利克带的强烈(A型)俯冲,正是这次俯冲引起了青藏高原及其外围山脉的快速隆升,中国西北的盆-山地貌因此而形成,其中东昆仑山推覆隆升近3000m,向北推挤近400km,是柴达木盆地、河西走廊新生界构造变形的主因。因此,“亚澳”陨击事件的影响,提供了青藏高原最晚一期隆升和中亚与中国西部大陆构造形成的大陆动力学背景;根据近年对阿尔金断裂带内同变形期新生矿物的激光微区40Ar/39Ar测年结果,阿尔金断裂走滑变形有可能起始于97~89Ma,它与喜马拉雅“西构造结”的形成(102~85Ma)近于同步,其累积错距达350~400km,晚白垩世—新生代同步错移了两侧原有的构造带和原型盆地,这为中国西部找矿、找油气的的战略评估提供了一个新的思路。 展开更多
关键词 青藏高原隆升 隆升动力学 “亚澳”陨击事件 阿尔金断裂 同步错移
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