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Analysis of the Spatial and Temporal Characteristics of Extreme Precipitation Events in Liaoning Province 被引量:5
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作者 王震 王颖 《Meteorological and Environmental Research》 CAS 2010年第10期39-42,共4页
Daily precipitation amounts from 1961 to 2005 in 35 observation stations in Liaoning Province were selected in order to study the temporal and spatial distribution of extreme precipitation events.By dint of EOF,REOF,m... Daily precipitation amounts from 1961 to 2005 in 35 observation stations in Liaoning Province were selected in order to study the temporal and spatial distribution of extreme precipitation events.By dint of EOF,REOF,mean-square-error and other ways,the changes in different regions of extreme precipitation and distribution were reflected.The analysis showed that,extreme precipitation in Liaoning Province could be divided into three areas,which were western Liaoning mountains and parts of northern areas,eastern Liaoning mountainous,near-coastal areas of Liaohe River Plain.In the relatively large precipitation areas,extreme precipitation threshold was also higher,and vice versa.The lower frequency of extreme precipitation events had a greater contribution to total precipitation;extreme precipitation,total precipitation and total rain days had the greatest changes in the summer,and the least changes in the winter;number of days of extreme precipitation changes in each season were not great;the change of extreme precipitation was not obvious in the long term. 展开更多
关键词 Extreme precipitation event spatial and temporal characteristic Twiddle factor Liaoning Province China
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Spatial-temporal Variation of Extreme Precipitation Events in Northwest China During 1961-2010 被引量:5
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作者 Lian Lishu Xu Shujing +1 位作者 Li Zhifu Sun Xiaoyin 《Meteorological and Environmental Research》 CAS 2014年第1期12-19,23,共9页
Using the daily precipitation data of 118 meteorological stations in Northwest China from January 1, 1961 to December 31,2010, we analyzed extreme precipitation events from prime precipitation data by applying R-langu... Using the daily precipitation data of 118 meteorological stations in Northwest China from January 1, 1961 to December 31,2010, we analyzed extreme precipitation events from prime precipitation data by applying R-language Climate Index (RClimDex). The spatial-temporal change characteristics in the past 50 years have been examined using the method of trend analysis, Mann-Kendall and the spatial analysis module of Arcgis9.2. The results show that the spatial distribution of the indices for extreme precipitation in Northwest China is greatly influenced by geographic location, atmospheric circulation and topography, and the spatial difference of extreme precipitation events is very evident, while the indices reduce from the southeast to the northwest except Consecutive Dry Days (CDD). In Xinjiang region, high values appear in Tianshan Mountains and decrease towards the south and north respectively. In the past 50 years, the temporal variation tendency of the indices for extreme precipitation in Northwest China has a great spatial distinction. It shows that the variation tendency is opposite between the east (decrease) and the west (increase), and CDD has a decreasing tendency while other indices increase. For each region, it is found that the indices for extreme precipitation in Xinjiang and Qinghai Province shows an increasing trend, and it is remarkable in Tianshan Mountains, the north of Xinjiang and the northeast of Qinghai Province. The temporal variation tendency of the indices for extreme precipitation in Ningxia, Shaanxi and Gansu has a large spatial distinction. The stations which have an increasing tend are mainly found in the north of Ningxia, south of Shaanxi and Hexi Corridor of Gansu. However, the south of Ningxia, north of Shaanxi and Longnan of Gansu Province mainly present a decreasing trend. The temporal variation tendency of the indices for extreme precipitation in Inner Mongolia is not obvious. Overall, the east part of Northwest China has a dry tendency, while the west part has an opposite trend. 展开更多
关键词 Northwest China Extreme precipitation events spatial-temporal variation characteristics Mann-Kendall method China
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Spatial and Temporal Variations of Extreme Climate Events in Xinjiang, China during 1961-2010 被引量:5
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作者 Xiangling Tang Xin Lv Yineng Ouyang 《American Journal of Climate Change》 2016年第3期360-372,共14页
Daily maximum/minimum temperature and precipitation data from 35 weather stations in Xinjiang during 1961-2010 were examined using kriging spatial analysis, linear tendency estimation, and correlation analysis. Tempor... Daily maximum/minimum temperature and precipitation data from 35 weather stations in Xinjiang during 1961-2010 were examined using kriging spatial analysis, linear tendency estimation, and correlation analysis. Temporal trends and spatial distribution patterns of extreme temperature and precipitation in this area were then analyzed using 12 extreme temperature and 7 extreme precipitation indices. The following results were obtained. 1) Over the past 50 years, extreme cold indices, excepting the monthly maximum temperature minimum value and monthly extreme minimum temperature, showed slight decreasing trends. These indices include the maximum number of consecutive frost days, icy days, cold-nighttime days, and cold-daytime days. 2) Extreme warm events generally showed significant increasing trends (P < 0.01), including the indices of summertime days, warm-nighttime days, warm-daytime days, monthly extreme maximum temperature, and monthly minimum temperature maximum value. 3) The spatial distributions of threshold values of extreme warm and cold events showed notable regional differences. A reducing trend of extreme cold events and an increase in extreme warm events has occurred mainly in northern Xinjiang. 4) For the past 50 years, six extreme precipitation indices, aside from consecutive dry days, showed significant increasing trends in Xinjiang (P < 0.05) and notable differences in spatial distribution. The increase in extreme precipitation events was more rapid at northern than at southern sites. Extreme precipitation intensity was greater in mountainous areas, and precipitation frequency increased in the plain region. 5) Factor analysis revealed good correlations among extreme temperature indices, excepting extreme temperature days. 展开更多
关键词 Xinjiang Area Extreme Climatic event spatial Change
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Effect of Neurofeedback on Visual-Spatial Attention in Male Children with Reading Disabilities: An Event-Related Potential Study
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作者 Neda Sadeghi Mohammad Ali Nazari 《Neuroscience & Medicine》 2015年第2期71-79,共9页
Recent studies describe a number of difficulties associated with attention deficit in children with reading disabilities. Information about visual-spatial attention mainly arises from studies using event-related poten... Recent studies describe a number of difficulties associated with attention deficit in children with reading disabilities. Information about visual-spatial attention mainly arises from studies using event-related potentials (ERPs) during Posner’s spatial cueing paradigm. This study aims to use neurofeedback with a special protocol for treating children with reading disabilities, and moreo-ver, to evaluate visual-spatial attention ability by means of Posner paradigm task and ERPs. The study was conducted in a single subject design in 20 sessions. Participants were 2 male children, aged between 10 - 12 years old, who completed twelve 30-min neurofeedback sessions. Repeated measurements were performed during the baseline, treatment, and post treatment phases. Results showed some improvement in Posner paradigm parameters (correct response, valid and invalid reaction times). Furthermore, grand average ERPs for both of the participants in each of the four conditions (Valid-right, Invalid-right, Valid-left and Invalid-left) were analyzed. The analysis of P3 component showed a reduction in latency, indicating an improvement in the timing of cognitive processes. In addition, the graphs showed a decrease in amplitude level, which meant easier processing than before. 展开更多
关键词 NEUROFEEDBACK READING DISABILITY Visual-spatial Attention ERP event-RELATED POTENTIALS
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Analysis on Spatial and Temporal Changes of Extreme Precipitation Events in Ningxia in Recent 50 Years
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作者 LI Xin ZHENG Guang-fen +1 位作者 NA Li WANG Su-yan 《Meteorological and Environmental Research》 2012年第6期22-25,29,共5页
[ Objective] The aim was to study the spatial and temporal changes of extreme precipitation events in Ningxia in recent 50 years. [ Method] Using dally precipitation data at 20 stations in Ningxia from 1961 to 2010, a... [ Objective] The aim was to study the spatial and temporal changes of extreme precipitation events in Ningxia in recent 50 years. [ Method] Using dally precipitation data at 20 stations in Ningxia from 1961 to 2010, and defining the threshold value of extreme precipitation in each sta- tion by percentage method, choosing indicators such as precipitation, frequency and intensity of extreme precipitation events, the characteristics of the spatial and temporal distribution and linear trend of extreme precipitation events in Ningxia were analyzed based on linear regression and M-K non-parameter statistical test method. [ Result] The percentage method suggested the threshold value of average extreme precipitation in Ningxia in recent 50 years decreased from south to north. The large threshold value was in southern Haiyuan, Tongxin and northern Yancheng, which was similar to the distribution of mean annual precipitation in Ningxia. In recent 50 years, extreme precipitation frequency and extreme precipitation de- creased in most part of Ningxia but the intensity tended to strengthen. Study of extreme precipitation in Mahuang Mountain and Liupan Mountain in- dicated that precipitation frequency, intensity and extreme precipitation reduced. Annual extreme precipitation frequency narrowed and then in- creased after 1994 and had mutation in 2003. Annual extreme precipitation intensity enhanced since 1984. Mutation took place in 1984. Intensity in Liupan Mountain had weakened since 1978. [ Conclusion] The study provided theoretical basis for the mutation of climate in Ningxia. 展开更多
关键词 Extreme precipitation events spatial and temporal changes Ningxia China
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THE TEMPORAL AND SPATIAL PATTERNS OF ENVIRONMENTAL RISK EVENTS IN THE PAST 30 YEARS IN SHENYANG CITY
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作者 Bi Jun Tang Yijian Zhang Shen(Institute of Geography, CAS, Beijing 100101People’s Republic of China)Wang Huadong(Institute of Environmental Sciences, Beijing Normal University, Beijing 100875People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1995年第1期76-86,共11页
The index of Risk Frequency (RF) and other relative indices are used to analyze the temporal and spatial patterns of environmental riskevents in the past 30 years in Shenyang city. The results show that thereexists si... The index of Risk Frequency (RF) and other relative indices are used to analyze the temporal and spatial patterns of environmental riskevents in the past 30 years in Shenyang city. The results show that thereexists significant difference of the RFs between periods of 1966-1977 and1978-1991 (t=7.353**, t0.01=2.807). During the past 30 years, there areno significant changes of the spatial patterns of the environmental risk,while the proportions of environmental risk among the districts are extremely different. In Shenyang city, there exists a series of high riskenterprises, and the chemical industry is the one with highest risk. 展开更多
关键词 environmental risk events temporal and spatial patterns risk frequency
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Study on Temporal-spatial Change Characteristics of the Extremely Low Temperature Climate Event in Winter of China
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作者 Zhonghong Luo Hangdong Jiang +1 位作者 Jiangyong Pan Jiayou Huang 《Meteorological and Environmental Research》 CAS 2013年第4期10-13,16,共5页
[ Objective] The research aimed to study temporal-spatial change characteristics of the extremely low temperature climate event in winter of China. [MethodI By using actual probability distribution threshold value met... [ Objective] The research aimed to study temporal-spatial change characteristics of the extremely low temperature climate event in winter of China. [MethodI By using actual probability distribution threshold value method, EOF analysis method and the daily minimum temperature data in winter of 1961 -2008 at 195 observatories of China, temporal-spatial change characteristics of the extremely low temperature climate event in win- ter of China in 48 years were analyzed. [ Result] Threshold value calculated by actual probability distribution was higher than that by traditional method, and increase magnitude in east was bigger than that in west, which could describe climatic change situation in China in 48 years better than traditional method. Cold night number in winter of China did not decrease as latitude declined, and it was more in south and north and was less in Yellow River basin and northwest China. Cold night number was the most in northeast Inner Mongolia. Interannual change of the cold night number presented decline tendency. From the 1960s to the eady 1970s, cold night number consistently increased, and change in middle and late periods of the 1960s was severe. From the early 1970s to the middle 1980s, fluctuation of the cold night number was bigger, and increase of the cold night number was the most in 1976. Cold night number from 1986 to the 21= century continuously declined. Change of the cold night number was the most obvious in east region, Guizhou and north Guangxi. Cold night number in northeast China and north Inner Mongolia presented inverting change relationship with that in Yunnan - Kweichow Plateau and Hexi Corridor. [ Conclusion] The research provided reference for eady warning of the extremely low temoerature event in China. 展开更多
关键词 Minimum temperature Extremely low temperature event Cold night Temporal-spatial change characteristics China
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Spatial Analysis of Affected Areas by Extreme Hydrological Events in Rio de Janeiro (The Host City for the 2016 Olympic Games)—Brazil
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作者 Leandro Andrei Beser de Deus Camilla Silva Motta Santos +2 位作者 Patricia Gomes da Silveira Marcos Aurélio Vasconcelos Freitas Paulo Márcio Leal Menezes 《Journal of Geographic Information System》 2013年第4期337-346,共10页
The most frequent types of disasters in Brazil are associated with extreme hydrological events. Adding to this situation, in Brazil, there are the extreme sociospatial discrepancies that are historically constructed. ... The most frequent types of disasters in Brazil are associated with extreme hydrological events. Adding to this situation, in Brazil, there are the extreme sociospatial discrepancies that are historically constructed. They leave marks in space, making specific areas, for political interest or not, more vulnerable to the different mentioned processes. To this extent, the public management should plan actions and, also, it may act in a more holistic way adding new trends, such as, the use of geotechnologies that are applied to environmental management in the realm of urban planning. From a case study in the city of Rio de Janeiro, this paper aims to contribute and draw attention to such issues. It may reach its target through pointing and spatially analyzing which areas are in the most critical situation related to the occurrence of extreme hydrological events. To achieve this goal, it was proposed a methodology to inventory the occurrence of inundation/flooding for a certain period, in this case 2001-2008. Besides, the methodology could systematize data and integrate them with other important issues for supporting the process of identification and analysis of the most critical areas. Historical aspects of occupation and the most vulnerable socio-environmental aspects were raised, too, in order to validate the highlighted areas. This integration was enabled concerning the support of geoprocessing techniques. The results of this integration subsidized the mapping and spatial analysis of the affected areas in the city and the criticality in relation to the extreme hydrological events. Finally, it was possible to observe that the identification of the most critical affected areas does not mean the exhaustion of the subject. The location of these areas is directly linked to the sample that was used as the basis for analyses. This data set only represents recorded events by the Municipal Civil Defense respecting the studied time frame. However, the results permit to take notes and raise relevant environmental questions about the roots and the occurred impacts that were originated from the extreme hydrological events, which have been observed in recent decades. 展开更多
关键词 EXTREME eventS FLOOD Hazards GIS Hydric RESOURCES spatial Analysis
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Identifying the Spatial Structure of Black Hole and Tropical Cyclone Based on a Theoretical Analysis of Orthogonal Interaction
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作者 Weihong Qian 《Journal of Modern Physics》 CAS 2023年第6期933-952,共20页
Black holes are recognized by Newton’s gravitational theory and Einstein’s general relativity, but there is still a lack of understanding the spatial structure of events, especially the nature of event horizon. In t... Black holes are recognized by Newton’s gravitational theory and Einstein’s general relativity, but there is still a lack of understanding the spatial structure of events, especially the nature of event horizon. In this paper, a theoretical analysis is used to compare the structures of tropical cyclone in the atmosphere and black hole in the astronomy so that five results are: 1) Both of them share the similar spatial structure, with tropical cyclone and black hole having the outflow cloud shield and the horizon sphere in the central part, respectively, while four spiral material bands exist in the rotating plane around them;2) In theoretically, the energy density formed by the orthogonal interaction of the four spiral material bands is as times as the total kinetic energy of the head-on interaction;3) This region of high energy density can lead to the conversion from mass to energy and the creation of new physical states of matter, which is a black hole event;4) The outer horizon of a black hole is the outermost interface of events, or the orthogonal interaction interface of particles;5) High-speed plasma jets extended at the poles of the black hole are directly associated with the shear stress of orthogonal interaction. 展开更多
关键词 Black Hole event Horizon Tropical Cyclone spatial Structure Orthographic Interaction
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体育赛事、环境规制与城市环境治理效率——基于中国百强城市的实证研究 被引量:1
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作者 李军林 路嘉明 +1 位作者 王禹辰 李树旺 《天津体育学院学报》 CAS 北大核心 2024年第3期258-266,共9页
大型体育赛事具有广泛的社会、经济影响力。如何利用举办体育赛事促进城市发展、改善生态环境是建设体育强国,促进体育事业高质量发展的重要一环。新时代以来,在绿色新发展理念的指导下,环保和可持续发展成为体育赛事的重要目标,地方政... 大型体育赛事具有广泛的社会、经济影响力。如何利用举办体育赛事促进城市发展、改善生态环境是建设体育强国,促进体育事业高质量发展的重要一环。新时代以来,在绿色新发展理念的指导下,环保和可持续发展成为体育赛事的重要目标,地方政府也因此以举办大型体育赛事为契机,提升环境规制水平,以期体育赛事成为推动城市绿色发展的动力之一。使用DEA-SBM模型测算我国百强城市的环境治理效率,并使用空间双重差分法分析我国百强城市2010—2019年申办的国家以上级别综合性体育赛事对城市环境治理、环境规制以及绿色创新的影响。结果表明,大型赛事的申办会显著提高举办城市的环境治理效率,该结果在控制城市产业结构、人力资本水平、工业行业规模、环境治理支出等有可能造成影响的变量后依然成立。通过机制检验发现,大型体育赛事能够通过提高举办地的环境规制强度和绿色创新强度两条路径提高环境治理效率。研究证明,中国的体育赛事已经成为积极、高效的环境治理方式之一,能够长期促进城市新质绿色生产力的发展。 展开更多
关键词 体育赛事 绿色创新 环境治理效率 空间DID 新质生产力
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抽象性位移事件及其汉语编码的认知阐释
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作者 张克定 《天津外国语大学学报》 2024年第5期10-19,111,共11页
作为认知主体的人不仅有能力识解出抽象性位移事件,而且有能力将其编码为特定的语言结构并用于交际。作为一种特殊的位移事件,抽象性位移事件的形成是有认知理据的,这一认知理据就是抽象实体的可动化机制。该机制有其自身的认知特性,其... 作为认知主体的人不仅有能力识解出抽象性位移事件,而且有能力将其编码为特定的语言结构并用于交际。作为一种特殊的位移事件,抽象性位移事件的形成是有认知理据的,这一认知理据就是抽象实体的可动化机制。该机制有其自身的认知特性,其使用会受到一定的条件限制。编码抽象性位移事件的语言表达式可以叫作抽象性空间位移关系构式。汉语抽象性空间位移关系构式的构成既要受到整体性限制条件的制约,又要受到局部性限制条件的制约。 展开更多
关键词 抽象性位移事件 编码 汉语抽象性空间位移关系构式 认知机制 限制条件
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VR音频技术在体育赛事节目制作中的应用研究
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作者 黄子轩 胡泽 《中国传媒大学学报(自然科学版)》 2024年第2期52-59,共8页
随着广播电视相关技术的不断成熟,对电视画面质量的探索经历了从标清技术到高清技术的转变,4K、8K等高清视频技术发展的同时,声音技术也在不断发展。全景声、三维声、空间音频的出现,让受众逐渐不满足于立体声甚至环绕声这类平面的声音... 随着广播电视相关技术的不断成熟,对电视画面质量的探索经历了从标清技术到高清技术的转变,4K、8K等高清视频技术发展的同时,声音技术也在不断发展。全景声、三维声、空间音频的出现,让受众逐渐不满足于立体声甚至环绕声这类平面的声音呈现方式,对定位的精确度、空间的还原度提出了更高的要求与期望。在媒介环境学视域下,人们的注意力从单一的视觉中心转向听觉,进一步追求感官上的和谐平衡。本文围绕体育赛事节目中VR音频(又被称为空间音频)的制作,对体育赛事节目中音频带来的多维沉浸进行了分析,并进一步探讨技术变革带来的审美变迁。最后设想了在体育转播声音制作中建立以人的感知为中心的声场,充分利用听觉元素调动多个感官,使观众整体沉浸于比赛之中。打破体育赛事节目中观众传统的听觉习惯是值得尝试的,声音创作在未来将朝着更加自由且人性化的方向发展。 展开更多
关键词 VR音频 空间音频 体育赛事 沉浸感
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1981-2020年沂沭河流域极端降水事件特征及环流背景 被引量:1
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作者 刘婷婷 申高航 谢晓华 《沙漠与绿洲气象》 2024年第3期69-77,共9页
利用1981-2020年沂沭河流域12个气象台站逐日降水观测资料,西太平洋副热带高压(WPSH)指数、太平洋年代际振荡指数(PDO)以及NCEP/NCAR逐日再分析资料,采用统计分析、合成分析等方法,研究沂沭河流域极端降水事件的时空变化特征,研究极端... 利用1981-2020年沂沭河流域12个气象台站逐日降水观测资料,西太平洋副热带高压(WPSH)指数、太平洋年代际振荡指数(PDO)以及NCEP/NCAR逐日再分析资料,采用统计分析、合成分析等方法,研究沂沭河流域极端降水事件的时空变化特征,研究极端降水指数与气候因子之间的相关性以及极端降水事件的异常环流背景。结果表明:沂沭河流域的极端降水事件整体上呈增多且强度增强的趋势,空间分布上南多北少,中部和北部的增速明显高于南部。极端降水频次和年极端降水量均在1989和2002年左右突增;极端降水强度在1989年突增,2000年左右突减。极端降水的频次、强度和年极端降水量分别以22、10、22 a的周期波动为主。西太平洋副热带高压的脊线位置与频次和年极端降水量呈正相关,PDO与频次和年极端降水量呈负相关。东亚夏季风强度和西太平洋副热带高压的位置是影响沂沭河流域极端降水事件的重要因素,可为预测该流域极端降水提供参考。 展开更多
关键词 沂沭河流域 极端降水事件 时空分布 环流特征
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考虑地震事件内空间相关性的区域概率地震危险性分析
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作者 丁佳伟 吕大刚 曹正罡 《工程力学》 EI CSCD 北大核心 2024年第S01期117-128,共12页
一次地震事件不同地点的地震动强度参数与结构响应参数之间是空间相关的,相关的地震效应将导致地震损失急剧集中与积累,从而造成灾难性事件,但是现有的区域尺度地震风险评估并没有考虑地震动的空间相关性。该文采用地统计学方法表征地... 一次地震事件不同地点的地震动强度参数与结构响应参数之间是空间相关的,相关的地震效应将导致地震损失急剧集中与积累,从而造成灾难性事件,但是现有的区域尺度地震风险评估并没有考虑地震动的空间相关性。该文采用地统计学方法表征地震事件内地震动强度参数的空间相关性,提出了理论半变异函数的几何稳健估计方法,并采用加权最小二乘法实现对短距离空间相关性的准确高效评估。以新潟越冲地震为例,基于指数半变异函数模型,采用加权最小二乘法对几何稳健估计半变异函数值进行拟合,得到了PGA、PGV和0 s~10 s谱加速度的空间相关性函数,提出了变程b值的预测模型,结果表明:相比于短周期谱加速度,长周期谱加速度的空间相关性衰减速率更小,且在T=0.45 s处存在拐点。将所开发的空间相关性模型应用于区域概率地震危险性分析,采用Monte Carlo方法实现了空间相关随机场的区域地震动强度参数的模拟,改进了传统区域地震危险性分析的方法,发现绝大多数情况下考虑空间相关性的年超越概率大于未考虑空间相关性的年超越概率,表明考虑空间相关性对于建筑群落及基础设施风险评估、韧性城市建设等具有重要的指导意义。 展开更多
关键词 事件内残差 空间相关性 几何稳健估计 加权最小二乘法 半变异函数 区域危险性分析
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开源文本中军事目标动向事件抽取方法研究
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作者 张宇恒 郑胜 陈晓玥 《武汉工程大学学报》 CAS 2024年第3期299-303,共5页
从海量非结构化的开源军事目标动向文本中抽取指定军事目标的事件信息以及运动轨迹,是识别和预测军事目标的行动意图、挖掘战场动态信息的基础工作。针对目前事件抽取研究中忽略地点论元之间空间关系信息从而导致无法抽取移动目标的运... 从海量非结构化的开源军事目标动向文本中抽取指定军事目标的事件信息以及运动轨迹,是识别和预测军事目标的行动意图、挖掘战场动态信息的基础工作。针对目前事件抽取研究中忽略地点论元之间空间关系信息从而导致无法抽取移动目标的运动轨迹问题,提出划分细粒度空间关系标签的方法来识别空间关系,通过序列标注方法进行事件抽取,使用预训练语言模型进行底层语义编码、双向长短时记忆网络进行深层次特征提取、条件随机场进行标签分类的联合事件抽取模型以完成动向事件抽取。在动向事件抽取结果的基础上,使用运动轨迹抽取算法来加强空间关系信息。通过在自建的真实军事目标动向新闻数据集上进行实验,获取了84.0%的F1分数值。 展开更多
关键词 开源军事情报 事件抽取 空间关系识别 深度学习
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多套降水产品在海南岛的适用性评估
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作者 李世禧 廖玮杰 +4 位作者 尚明 郭建超 施晨晓 杨岳 白磊 《热带地理》 CSCD 北大核心 2024年第9期1588-1601,共14页
使用卫星遥感技术进行全球范围的降水观测已成为当前热点。然而,热带海岛地区因其气候特殊和地形复杂,遥感降水数据的精度评估尚未充分研究。文章以海南岛为研究区,利用小时尺度的站点数据对CMORPH、CHIRPS、GsMAP、GPM、MSWEP、ERA5-L... 使用卫星遥感技术进行全球范围的降水观测已成为当前热点。然而,热带海岛地区因其气候特殊和地形复杂,遥感降水数据的精度评估尚未充分研究。文章以海南岛为研究区,利用小时尺度的站点数据对CMORPH、CHIRPS、GsMAP、GPM、MSWEP、ERA5-Land和PERSIANN进行多尺度系统评估,分析各类产品在该区域的降水探测能力。结果表明:1)相比于其他5种降水产品,GsMAP和GPM在不同时间尺度上均具有更优表现,相关性强,误差小,对各级降水的探测成功率较高。在3 h尺度上,GPM和GsMAP的相关系数分别为0.53和0.52;在日尺度上,GPM和GsMAP的相关系数分别为0.73和0.74。2)在年降水量对比中,过去20年海南岛的年平均降水量呈现波动中变化趋势,平均值为1776.4 mm/a。CMORPH的年平均值为1765.1 mm/a,与CHM-PRE数据集最为接近,误差较小。3)在空间分布格局研究中,GsMAP的降水量范围为1337.9~2287.0 mm,与站点观测数据(996.9~2368.9 mm)最为接近,呈现东部多于西部,西南山区多于东北平原的环状分布格局,尤其在海南岛东南部的高值中心区域,二者较吻合。4)在降水趋势分析中,CMORPH、ERA5-Land、GPM、MSWEP、CHIRPS和PERSIANN在海南岛部分地区呈现增加趋势,而GsMAP呈现较为强烈的增加趋势。5)在极端降水事件分析中,GPM能较好地模拟海南岛台风降水事件的时空演变特征。因此,在开展海南岛降水研究工作时,GsMAP和GPM是比较合适的选择。 展开更多
关键词 时空格局 极端降水事件 气候变化 多尺度 海南岛
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松花江流域NPP时空演变及其对极端气候的响应机制
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作者 贾朝阳 郭亮 +2 位作者 崔嵩 付强 刘东 《南水北调与水利科技(中英文)》 CAS CSCD 北大核心 2024年第1期131-147,共17页
为探究全球气候变化条件下松花江流域陆地生态系统健康程度的变化特征,基于2000—2020年MODIS MOD17A3HGF数据集,采用趋势分析、相关性分析、M-K检验、地理探测器和相对重要性分析等方法,结合气象站点数据和土地利用数据,分析植被净初... 为探究全球气候变化条件下松花江流域陆地生态系统健康程度的变化特征,基于2000—2020年MODIS MOD17A3HGF数据集,采用趋势分析、相关性分析、M-K检验、地理探测器和相对重要性分析等方法,结合气象站点数据和土地利用数据,分析植被净初级生产力(net primary productivity,NPP)时空演变特征及其对极端气候事件的响应机制。结果表明:松花江流域年均NPP值为407.45 g/m^(2)(以C计,下同),以年均4.82 g/m的速率显著上升(p<0.01);极端降水事件对植被NPP空间分异性的影响强于极端气温事件,极端气候指数间交互作用的影响大于单一极端气候指数的影响,流域及农田和草地生态系统NPP主要受总降水量(PRCPTOT)与年平均最低气温(TMIN)交互作用的影响,森林、湿地和聚落生态系统NPP分别受中雨日数(R10 mm)与年平均最高气温(TMAX)交互作用、强降水量(R95P)与TMIN交互作用和R10 mm与暖夜日数(TN90P)交互作用的影响;时间尺度上PRCPTOT、TMAX和TMIN是植被NPP的主要影响因素,空间尺度上PRCPTOT和TMIN是多年平均NPP的主要影响因素。研究结果可为量化气候变化背景下区域生态系统健康程度和应对极端气候事件措施的制定提供科学依据。 展开更多
关键词 松花江流域 净初级生产力 极端气候事件 陆地生态系统 时空演变规律 驱动因素 地理探测器
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基于标准化指数的中国东北地区复合高温干旱事件时空变化特征分析
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作者 张雪玲 朱美琪 李颖 《河北省科学院学报》 CAS 2024年第1期1-10,共10页
干旱和极端高温事件会对人类社会和生态环境造成严重影响,当两种极端事件同时发生时会造成更大的威胁。本文利用1961-2020年网格化的月值降水和气温数据,计算标准化降水蒸散发指数(SPEI)和标准化温度指数(STI),在界定复合事件的基础上... 干旱和极端高温事件会对人类社会和生态环境造成严重影响,当两种极端事件同时发生时会造成更大的威胁。本文利用1961-2020年网格化的月值降水和气温数据,计算标准化降水蒸散发指数(SPEI)和标准化温度指数(STI),在界定复合事件的基础上分析不同干热阈值下中国东北地区复合高温干旱事件的时空演变特征,探究复合事件的空间相关性。结果表明,中国东北地区复合高温干旱事件发生频率在空间分布表现出东部及东南部低、西部及西北部高的特点;分析复合事件的历史演变发现Mi-Mi以0.02/a速率上升,且在20世纪90年代之后大幅度升高;总体复合事件影响面积呈现显著的上升趋势,幅度为1.02%/a,不同类型复合事件影响面积均显著升高且在20世纪90年代大幅度上升达到峰值;复合事件的高频区聚集在西部和西北部,低频区聚集在东南部及东部。研究成果可为东北地区防灾减灾、农业规划、水资源配置等提供参考。 展开更多
关键词 复合高温干旱事件 时空特征 空间相关性 SPEI STI
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陕西秦岭以北地区清代霜雪灾害与寒冷气候事件研究
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作者 李嘉宁 岳大鹏 +1 位作者 赵景波 杨天宇 《地域研究与开发》 北大核心 2024年第4期174-180,共7页
运用灾害等级法、数理统计法、小波分析法等对清代陕西秦岭以北地区的霜雪灾害等级、时空分布、周期性及致灾因子进行研究。结果表明:(1)陕西秦岭以北地区清代(1644—1911年)268年内共发生霜雪灾害97次,1644—1703年和1864—1911年为高... 运用灾害等级法、数理统计法、小波分析法等对清代陕西秦岭以北地区的霜雪灾害等级、时空分布、周期性及致灾因子进行研究。结果表明:(1)陕西秦岭以北地区清代(1644—1911年)268年内共发生霜雪灾害97次,1644—1703年和1864—1911年为高频期,1704—1783年和1784—1863年为较低频期,且存在3年、7年、11年、28年的准周期。(2)霜雪灾害频次和等级存在季节性特征。霜灾在春秋两季最为频繁,雪灾在冬春季节发生最多,冻灾几乎仅在冬季发生。中度等级灾害多发生于春秋两季,重度等级灾害常发生于秋冬之际。(3)霜雪灾害的强弱与频次在空间上有较好一致性,多集中于陕北黄土高原北部和西北部以及关中盆地东南部。(4)霜雪灾害发生高频期对应气候更为寒冷干燥。冬季风强度是决定霜雪灾害发生的直接因素。(5)小冰期气候在清代最突出的特点是在较暖或炎热月份发生降温达15~20℃的灾难性降温事件,并导致灾难性天气过程。(6)清代陕西秦岭以北地区发生两次极端寒冷气候事件,分别在1662—1692年和1861—1900年,后者指示清代气温最低的时期。 展开更多
关键词 清代 霜雪灾害 时空变化 寒冷气候事件 陕西秦岭以北地区
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现象学视域下高校典型外部空间场所氛围研究
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作者 喻冬冬 于涵 《建筑与文化》 2024年第6期34-36,共3页
在梳理现象学相关概念与内容的基础上,文章试图从两个方面建立现象学与场所氛围关联的研究框架,从“身体-空间-氛围”和“行为-事件-场所”两个方面去讨论氛围与场所的关系,并尝试用场所氛围的概念解读校园中心广场等外部交往空间,以此... 在梳理现象学相关概念与内容的基础上,文章试图从两个方面建立现象学与场所氛围关联的研究框架,从“身体-空间-氛围”和“行为-事件-场所”两个方面去讨论氛围与场所的关系,并尝试用场所氛围的概念解读校园中心广场等外部交往空间,以此探讨现象学思想对于当代校园外部交往空间的内在影响与启发价值。 展开更多
关键词 现象学 空间氛围 场所事件 身体 行为
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