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41.
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
42.
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
43.
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
44.
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
45.
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46.
The Upper Middle Rhine Valley, granted the status of a World Heritage site, is well known for its unique inner narrow valley
of Quaternary age with its historical legacy of numerous medieval castles and old towns. Less known is that this has always
been a risk area of floods and gravitative mass movements. Up to the recent past, mainly ice floods caused enormous damage.
The inhabitants of the valley were well aware that they lived in a risk area, but they had learned to handle the flood hazard.
With the demise of ice floods over the last 40 years, due to climate change and because of the additional heating of the river
water by power plants, the awareness of flood hazards has been much diminished, in contrast to that of potential damage by
rockfalls and landslides which were also much feared in the past, though at the local level only. Still in the people’s memory
is the Kaub catastrophe of March 10, 1876, when 28 persons were killed by a landslide. Nowadays, even minor rockfalls are
a major threat, as they will affect the much-used traffic lines on both banks of the river, in particular the railroads. Therefore,
since 2002, on behalf of German Rail (Deutsche Bahn, DB), all problematic slopes have been protected by costly steel-ring nets, although they are an aesthetic problem by UNESCO
standards. The feeling of absolute safety created among the public is only subjective, though, as planners are well aware
of. Moreover, the impact of modern climate change on slope stability is nearly unknown. Therefore, it is still necessary to
develop a risk map for the narrow valley, with emphasis on gravitational hazards. 相似文献
47.
48.
Temporal and spatial dynamical simulation of groundwater characteristics in Minqin Oasis 总被引:3,自引:0,他引:3
XIAO DuNing LI XiaoYu ? SONG DongMei & YANG GuoJing Cold Arid Regions Environmental Engineering Research Institute Chinese Academy of Sciences Lanzhou China Institute of Applied Ecology Chinese Academy of Sciences Shenyang China Institute of Geographic Sciences Natural Resources Research Chinese Academy of Sciences Beijing China 《中国科学D辑(英文版)》2007,50(2):261-273
Application scope of geostatistics has been gradually extended from original geologic field to soil science and ecological field, etc. and its successful application results have been widely demonstrated. But little information is reported as to the direct use of geostatistical method to work out the distribu- tion map of groundwater characteristics. In this paper the semivariogram of geostatistics, in combina- tion with GIS, was used to quantitatively study the spatial variation characteristics of groundwater table depth and mineralization degree and their relation to the landuse changes. F test of the used spherical model reached a very significant level, and the theoretical model can well reflect the spatial structural characteristics of groundwater table depth and mineralization degree and achieve an ideal result. This shows that the application of the method in the dynamical simulation of groundwater is feasible. And this paper also provides useful reference for the application of geostatistics in the study of the dy- namical variations of groundwater resources in the oasis. 相似文献
49.
Power spectra of segmentation-cell length (a dominant length scale of EUV emission in the transition region) from full-disk He?ii extreme ultraviolet (EUV) images observed by the Extreme ultraviolet Imaging Telescope (EIT) onboard the Solar and Heliospheric Observatory (SOHO) and the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO) during periods of quiet-Sun conditions for a time interval from 1996 to 2015 were analyzed. The spatial power as a function of the spatial frequency from about 0.04 to 0.27 (EIT) or up to 0.48 (AIA) Mm?1 depends on the distribution of the observed segmentation-cell dimensions – a structure of the solar EUV network. The temporal variations of the spatial power reported by Didkovsky and Gurman (Solar Phys. 289, 153, 2014) were suggested as decreases at the mid-spatial frequencies for the compared spectra when the power curves at the highest spatial frequencies of 0.5 pix?1 were adjusted to match each other. This approach has been extended in this work to compare spectral ratios at high spatial frequencies expressed in the solar spatial frequency units of Mm?1. A model of EIT and AIA spatial responses allowed us to directly compare spatial spectral ratios at high spatial frequencies for five years of joint operation of EIT and AIA, from 2010 to 2015. Based on this approach, we represent these ratio changes as a long-term network transformation that may be interpreted as a continuous dissipation of mid-size network structures to the smaller-size structures in the transition region. In contrast to expected cycling of the segmentation-cell dimension structures and associated spatial power in the spectra with the solar cycle, the spectra demonstrate a significant and steady change of the EUV network. The temporal trend across these structural spectra is not critically sensitive to any long-term instrumental changes, e.g. degradation of sensitivity, but to the change of the segmentation-cell dimensions of the EUV network structure. 相似文献
50.
根据琼东南盆地深水区高分辨率2D/3D地震资料精细解释,和基于三维地震资料的相干分析,在琼东南盆地中央峡谷区发现了多期次的块体搬运沉积体系(MTDs)。研究表明,该区域块体搬运沉积体系包括3个主要的结构单元,即头部拉张区、体部滑移区和趾部挤压区,不同位置地震特征不同。大规模的块体搬运沉积体系构成了琼东南盆地中央峡谷区新近系以来地层中的重要沉积单元,并对深海沉积物的空间展布有重要的控制作用。上新世发育的一期块体搬运沉积体系,分布面积达300 km2,厚度达240 m,平面展布形态似扇形。高沉积物供给速率和不断的构造活动可能是该区域MTDs发育的主要原因。此外,地震活动、海平面变化也间接影响了MTDs的发育。 相似文献