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121.
气象部门素来有通过视频会议进行天气会商的传统,但受限于技术条件,多年以来天气会商只能在气象部门内网环境中进行。为满足用户基于互联网接入天气会商的需要,国家气象信息中心于2019年建设完成了气象云会商系统。该系统依托国产的互联网视频会议产品,采用专有云方式进行了部署,并实现了与气象部门已有的基于H.323协议视频会议系统的融合对接。通过在多个云会商系统间设置友好企业方式,不仅满足了气象部门系统分级和属地化管理的要求,也极大的提升了跨部门会商联动的简便性。本文对该系统的设计方案及关键技术进行了阐述,并介绍了其在重大活动气象服务及气象部门迎战新冠肺炎疫情过程中的应用效果,也提出了下一步云会商业务的发展方向。  相似文献   
122.
ABSTRACT

This research examines how people subjectively perceive the disclosure risk of a map using original data collected in an online survey with 856 participants. The results indicate that perceived disclosure risk increases as the amount of locational information displayed on a map increases. Compared to point-based maps, perceived disclosure risk is significantly lower for kernel density maps, convex hull maps, and standard deviational ellipse maps. The results also revealed that perceived disclosure risk is affected by map scale and the presence of information of other people on a map. For geomasking methods, perceived disclosure risk decreases as aggregation level increases and as relocation distance increases. However, aggregation methods (point to polygon) are more effective in preventing the re-identification of individuals when compared to relocation methods (point to point). Lastly, the perceived disclosure risk of a map that displays socially-vulnerable people is significantly higher than that of a map that displays non-vulnerable groups. Specifically, a map displaying the private locations of elementary school students has the highest perceived disclosure risk. Based on the results, a set of geoprivacy protection guidelines for mapping people’s private locations to minimize people’s perceived disclosure risk is proposed. Implications for mapping infectious diseases like the COVID-19 are also discussed.  相似文献   
123.
Conclusions are divided regarding the role of the variations of thermodynamics in the monsoon activity for the South China Sea region. In this study, primary eigenvectors are studied for the SSTA from East Asia to the tropical eastern Indian Ocean in May. The results show that temperature anomalies that center on Sumatra are closely related with the outbreak of the South China Sea monsoon. When the SST is warmer (cooler) than average year, it is likely that the monsoon set in late (early). It may be caused by the changes in meridional difference in thermodynamics between the Indochina Peninsula and its southern tropical oceans. Studying the temporal and spatial evolution of primary eigenvector distribution of the SSTA in the South China Sea-tropical eastern Indian Ocean from winter to summer, we find that the temperature anomalies that center around Sumatra in late spring and early summer can be traced back to the variations of the SST fields in the South China Sea in the preceding winter. Being well associated with the outbreak of the South China Sea monsoon, the latter is a signifi-cant index for it. The work helps understanding the atmospheric and oceanic background against which the South China Sea monsoon breaks out and behaves.  相似文献   
124.
气候变化影响下高山区泥石流形成机制研究及展望   总被引:3,自引:1,他引:2  
全球范围内高海拔或高纬度山区(以下简称高山区),尤其高山冰川冻土急剧消退地区,广泛发育泥石流灾害。在全球气候变暖的大背景下,高山区泥石流的现实危害和潜在风险日渐凸显。与其他环境条件下泥石流过程主要由降雨激发不同,高山区泥石流的暴发多受降雨和温度条件的共同影响,其形成机制更为复杂,预测预警十分困难,因此加强高山区泥石流研究具有重要的科学价值和实践意义。通过述评近期高山区泥石流起动研究的主要进展,包括泥石流暴发与气象条件的关系,典型高山区泥石流事件成因,冰川冻土体消融破坏机制,以及冰碛土泥石流起动特征,认为未来高山区泥石流研究应加强高时空分辨率气象数据获取和物源动态变化分析研判,并从动力学机制层面进一步明晰高山区泥石流起动条件和发育过程。  相似文献   
125.
Ongoing uncertainty over the relative importance of aerosol transmission of COVID-19 is in part rooted in the history of medical science and our understanding of how epidemic diseases can spread through human populations. Ancient Greek medical theory held that such illnesses are transmitted by airborne pathogenic emanations containing particulate matter (“miasmata). Notable Roman and medieval scholars such as Varro, Ibn al-Khatib and Fracastoro developed these ideas, combining them with early germ theory and the concept of contagion. A widely held but vaguely defined belief in toxic miasmatic mists as a dominant causative agent in disease propagation was overtaken by the science of 19th century microbiology and epidemiology, especially in the study of cholera, which was proven to be mainly transmitted by contaminated water. Airborne disease transmission came to be viewed as burdened by a dubious historical reputation and difficult to demonstrate convincingly. A breakthrough came with the classic mid-20th century work of Wells, Riley and Mills who proved how expiratory aerosols (their “droplet nuclei”) could transport still-infectious tuberculosis bacteria through ventilation systems. The topic of aerosol transmission of pathogenic respiratory diseases assumed a new dimension with the mid-late 20th century “Great Acceleration” of an increasingly hypermobile human population repeatedly infected by different strains of zoonotic viruses, and has taken centre stage this century in response to outbreaks of new respiratory infections that include coronaviruses. From a geoscience perspective, the consequences of pandemic-status diseases such as COVID-19, produced by viral pathogens utilising aerosols to infect a human population currently approaching 8 billion, are far-reaching and unprecedented. The obvious and sudden impacts on for example waste plastic production, water and air quality and atmospheric chemistry are accelerating human awareness of current environmental challenges. As such, the “anthropause” lockdown enforced by COVID-19 may come to be seen as a harbinger of change great enough to be preserved in the Anthropocene stratal record.  相似文献   
126.
《China Geology》2022,5(3):402-410
This study investigated water samples collected from the surface water and groundwater in Wuhan City, Hubei Province, China in different stages of the outbreak of the coronavirus disease 2019 (hereinafter referred to as COVID-19) in the city, aiming to determine the distribution characteristics of antiviral drugs in the city’s waters. The results are as follows. The main hydrochemical type of surface water and groundwater in Wuhan was Ca-HCO3. The major chemical components in the groundwater had higher concentrations and spatial variability than those in the surface water. Two antiviral drugs and two glucocorticoids were detected in the surface water, groundwater, and sewage during the COVID-19 outbreak. Among them, chloroquine phosphate and cortisone had higher detection rates of 32.26% and 25.80%, respectively in all samples. The concentrations of residual drugs in East Lake were higher than those in other waters. The main drug detected in the waters in the later stage of the COVID-19 outbreak in Wuhan was chloroquine phosphate, whose detection rates in the surface water and the groundwater were 53.85% and 28.57%, respectively. Moreover, the detection rate and concentration of chloroquine phosphate were higher in East Lake than in Huangjia Lake. The groundwater containing chloroquine phosphate was mainly distributed along the river areas where the groundwater was highly vulnerable. The residual drugs in the surface water and the groundwater had lower concentrations in the late stage of the COVID-19 outbreak than in the middle of the outbreak, and they have not yet caused any negative impacts on the ecological environment.©2022 China Geology Editorial Office.  相似文献   
127.
《China Geology》2022,5(3):411-420
A large number of antibiotics have been discharged into rivers by human activities, posing a threat to aquatic ecosystems. The surface water of the Yellow River Basin also suffers antibiotic pollution, which hinders the improvement in the aquatic ecological environment. This study investigated and analyzed the characteristics and assessed the ecological risks of antibiotic pollution in surface water bodies such as canals, rivers and fish ponds in Kaifeng, Henan Province, which is a key city along the lower reaches of the Yellow River. The test results are as follows. A total of 15 types of antibiotics were detected in the surface water. They had a total antibiotic concentration of 12.2–249.9 μg/L, of which tetracyclines (TCs) and quinolones accounted for the highest percentages. Six types of quinolones had detection rates of up to 100%, and doxycycline (DC) and oxytetracycline (OTC) had average concentrations of 29.52 μg/L1 and 13.71 μg/L, respectively. The major canals with water diverted from the Yellow River had total concentrations of quinolones and TCs of 22. 0 μg/L and 14.9 μg/L, respectively, which were higher than those in previous studies. This phenomenon may be related to the decrease in the water flow of the Yellow River during the dry season and the increase in the antibiotic consumption of residents in the context of the Covid-19 outbreak. The upper reaches of the Huiji River in the Xiangfu District had higher antibiotic content than other districts in Kaifeng. Specifically, TCs accounted for 72.38%–91.84% of all antibiotics, and the DC and OTC concentrations were significantly higher than other antibiotics in the upper reaches. As indicated by the ecological risk assessment results, TCs had the highest ecological risks to green algae. Among them, DC had medium-high risks; TC, OTC, and chlortetracycline (CTC) had medium-high risks; trimethoprim (TMP) and lomefloxacin (LOM) had low risks; other TC antibiotics had no risk. Compared with green algae, most antibiotics showed higher ecological risks to daphnia and lower ecological risks to fish. DC and OTC dominate antibiotic pollutants in the surface water in Kaifeng City, and especially in Xiangfu District, where DC and OTC have medium-high risks. The TCs in the major Yellow River showed medium risks to both green algae and daphnia. It can be speculated that the antibiotic pollution in the Yellow River might pose a certain threat to the ecological security of water in Kaifeng City.©2022 China Geology Editorial Office.  相似文献   
128.
李涛  李宇  戴靓  王姣娥 《地理研究》2021,40(11):3225-3241
科学评估重大公共卫生事件扰动对节假日城际出行活动的影响对于科学预防疫情传播、提升城际出行安全性具有重要意义。文章利用百度迁徙平台提供的城际出行数据,系统探讨了COVID-19疫情影响下的“五一”小长假城际出行规模时序变化、格局变化与出行流格局特征,并基于空间计量模型剖析了疫情与节假日叠加背景下的城际出行影响因素。结果表明:受COVID-19疫情影响,2020年“五一”小长假期间的城际出行规模同比下降达46.0%,时段波动主要表现为省内波动,省外城际出行总体较为平稳;COVID-19疫情对城际出行的影响呈现出东北>东中部>西部的特征;COVID-19疫情显著降低了“五一”小长假城际出行范围,相较于正常期70%的城际出行联系集中在400km范围内,疫情影响下的70%的城际出行联系集中在250 km范围以内;GDP、城镇化率、行政等级等城市规模吸引力因素,公路密度与高铁等交通变量是影响“五一”期间城际出行的主要因素,但各变量对城际出行的影响在“五一”不同时段具有时间异质性。公路密度与有无高铁具有显著的正向作用;城镇化率在出行期与返程期对城际出行分别起到了显著负向与正向作用;旅游资源丰富度仅在出行期显著。  相似文献   
129.
新冠肺炎(COVID-19)疫情给农户生计发展带来了重大风险,而生计资本是抵御疫情冲击、阻断返贫危机的关键。论文以重点疫区湖北省及周边地区为研究区域,基于可持续生计分析框架,从生计资本“结构—存量”多维视角出发,采用内生转换回归模型分析疫区465户农户生计资本对疫情风险的抵御作用。研究发现:① 重点疫区农户生计资本总量不高,疫情可能诱发生计脆弱性但不是唯一要素,基层公共卫生建设也极为重要;② 生计资本对疫情风险有显著抵御效应,人力资本维度作用更为凸显,物质资本占比过高反而会削弱疫情应对能力;③ 农户生计资本结构与存量分布不均,家庭劳动力、健康投入、财富积累、居住环境、社会阅历等是核心要素;④ 疫后生计恢复主要依赖于人力与金融资本的积累,而帮扶关键在于应急和兜底保障,要根据区域农户生计特征拟定差异化的疫情常态防控举措。  相似文献   
130.
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