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31.
运用大数据文本挖掘和分析工具,对比新冠疫情期间武汉和非武汉地区居民所发布的微文,探究了武汉樱花在不同居民群体间情感效应的作用机制,研究发现:1)本地居民樱花微文的关注点多而分散,非本地居民的关注点少而集中;2)武汉樱花对不同地区居民情感的影响与疫情发展状况紧密相关;3)武汉樱花在疫情期间对武汉居民具有情感支持效应,对非武汉地区居民具有情感凝聚效应;4)疫情改变人的情感和景观解读背景,并赋予景观新的意义,新的景观意义反作用于居民,构成情感闭合回路。最后提出建议,抗疫恢复工作应多关注居民心理层面的缺失,从居民与城市、景观的情感关系入手,向武汉居民传达城市美好生活理念。 相似文献
32.
Wenwen Li Sizhe Wang 《International journal of geographical information science》2017,31(8):1562-1582
The increasing research interest in global climate change and the rise of the public awareness have generated a significant demand for new tools to support effective visualization of big climate data in a cyber environment such that anyone from any location with an Internet connection and a web browser can easily view and comprehend the data. In response to the demand, this paper introduces a new web-based platform for visualizing multidimensional, time-varying climate data on a virtual globe. The web-based platform is built upon a virtual globe system Cesium, which is open-source, highly extendable and capable of being easily integrated into a web environment. The emerging WebGL technique is adapted to support interactive rendering of 3D graphics with hardware graphics acceleration. To address the challenges of transmitting and visualizing voluminous, complex climate data over the Internet to support real-time visualization, we develop a stream encoding and transmission strategy based on video-compression techniques. This strategy allows dynamic provision of scientific data in different precisions to balance the needs for scientific analysis and visualization cost. Approaches to represent, encode and decode processed data are also introduced in detail to show the operational workflow. Finally, we conduct several experiments to demonstrate the performance of the proposed strategy under different network conditions. A prototype, PolarGlobe, has been developed to visualize climate data in the Arctic regions from multiple angles. 相似文献
33.
Impacts of Climatic Factors on Runoff Coefficients in Source Regions of the Huanghe River 总被引:4,自引:0,他引:4
CHEN Liqun LIU Changming LI Yanping WANG Guoqiang 《中国地理科学(英文版)》2007,17(1):047-055
Runoff coefficients of the source regions of the Huanghe River in 1956–2000 were analyzed in this paper. In the 1990s runoff of Tangnaihai Hydrologic Station of the Huanghe River experienced a serious decrease, which had at- tracted considerable attention. Climate changes have important impact on the water resources availability. From the view of water cycling, runoff coefficients are important indexes of water resources in a particular catchment. Kalinin baseflow separation technique was improved based on the characteristics of precipitation and streamflow. After the separation of runoff coefficient (R/P), baseflow coefficient (Br/P) and direct runoff coefficient (Dr/P) were estimated. Statistic analyses were applied to assessing the impact of precipitation and temperature on runoff coefficients (including Dr/P, Br/P and R/P). The results show that in the source regions of the Huanghe River, mean annual baseflow coefficient was higher than mean annual direct runoff coefficient. Annual runoff coefficients were in direct proportion to annual pre- cipitation and in inverse proportion to annual mean temperature. The decrease of runoff coefficients in the 1990s was closely related to the decrease in precipitation and increase in temperature in the same period. Over different sub-basins of the source regions of the Huanghe River, runoff coefficients responded differently to precipitation and temperature. In the area above Jimai Hydrologic Station where annual mean temperature is –3.9oC, temperature is the main factor in- fluencing the runoff coefficients. Runoff coefficients were in inverse relation to temperature, and precipitation had nearly no impact on runoff coefficients. In subbasin between Jimai and Maqu Hydrologic Station Dr/P was mainly affected by precipitation while R/P and Br/P were both significantly influenced by precipitation and temperature. In the area be-tween Maqu and Tangnaihai hydrologic stations all the three runoff coefficients increased with the rising of annual precipitation, while direct runoff coefficient was inversely proportional to temperature. In the source regions of the Huanghe River with the increase of average annual temperature, the impacts of temperature on runoff coefficients be-come insignificant. 相似文献
34.
GM4型磁通门磁力仪性能检验方法 总被引:5,自引:0,他引:5
目前,磁通门磁力仪广泛应用于观测地球磁场相对变化的仪器。相对于应用,仪器的性能测试不为人们所熟悉。本文针对GM4型磁通门磁力仪的噪声特性,频率特性,线性度,温度特性等关键性能指标的测试依据、测试方法及流程给予详细的阐述。 相似文献
35.
川西北地区是国内重要的岩金普查靶区。本文对松潘地区的地质特征,泛克立格法原理,及在本区的应用情况作了介绍,对主要计算步骤,给出基本结果,对计算获得的有意义异常区,进行地质解释,并将此方法与趋势面分析进行对比。 相似文献
36.
安徽铜陵新桥矿区二叠系栖霞组底部和石炭系黄龙组—船山组之间产出层状、似层状菱铁矿矿层。开展菱铁矿矿层成因研究对于深入剖析区域层控矽卡岩型铜铁矿床成矿机制具有重要意义。本文利用粉晶X射线衍射(XRD)、扫描电镜(SEM)对菱铁矿矿石进行矿物学研究,结果发现菱铁矿矿石主要由菱铁矿、石英、伊利石和有机质等组成,菱铁矿颗粒粒径较小,表面具有成岩自生的自形石英硬模的微结构,SEM原位微区成分分析显示菱铁矿中除了主量元素铁,还含有大量的锰、锌和钙。矿石中存在两种微结构和不同成因的石英:表面具菱铁矿硬模和次生加大结构的碎屑石英;具六方双锥、单锥以及生物成因球形的自生石英。菱铁矿矿石的组成和矿物表面微结构表明其为沉积成因,非岩浆热液起源。富有机质和亚铁的沉积菱铁矿层和沉积胶状黄铁矿层协同作用,可能是铜陵地区乃至长江中下游成矿带层状铜铁矿床层控性重要制约因素,以及可能作为燕山期中酸岩浆演化的氧化性含铜成矿流体卸载成矿的地球化学还原障。
相似文献37.
Zhao Kang Zhou Yun Yu Xiang Yan Yajing Song Yufeng Wang Junqiang Suo Tianyuan Guo Xiao 《Natural Resources Research》2021,30(5):3839-3852
Natural Resources Research - Depletion of shallow mineral resources caused by deep mining has become an inevitable trend, and deep mining can increase safety accidents and geological hazards.... 相似文献
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40.
Effect of a thermokarst lake on soil physical properties and infiltration processes in the permafrost region of the Qinghai-Tibet Plateau,China 总被引:1,自引:0,他引:1
Changes in the hydrological processes in alpine soil constitute one of the several key problems encountered with studying watershed hydrology and ecosystem stability against the background of global warming. A typically developing thermokarst lake was chosen as a subject for a study using model simulation based on observations of soil physical properties, infiltration processes, and soil moisture. The results showed that the selected thermokarst lake imposed certain changes on the soil infiltration processes and, with the degree of impact intensifying, the initial infiltration rate decreased. The greatest reduction was achieved in the area of moderate impact. However, the stable infiltration rate and cumulative infiltration gradually increased in the surface layer at a depth of 10 and 20 cm, both decreasing initially and then increasing, which is correlated significantly with soil textures. Moreover, the cumulative infiltration changed in line with steady infiltration rate. Based on a comparative analysis, the Horton model helps better understand the effect on the soil infiltration processes of the cold alpine meadow close to the chosen thermokarst lake. In conclusion, the formation of the thermokarst lake reduced the water holding capacity of the alpine meadow soil and caused the hydraulic conductivity to increase, resulting in the reduction of runoff capacity in the area of the thermokarst lake. 相似文献