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131.
陈福江 《测绘与空间地理信息》2012,(2):87-89
"数字城市"是城市新的增长点,这一概念的提出源于"数字地球",是城市化进程加快、可持续发展的必然要求。Skyline是当前世界应用较为广泛的3维软件之一,它能够快速地融合数据,更新场景数据库,展现3维地理空间数据,功能强大。文章探讨并实现了通过收集资料、数据预处理、建立3维地形空间数据库、快速3维建模、空间数据整合、系统集成等一系列步骤建立起的基于Skyline、以辽宁省某市景观带为项目区的3维漫游系统关键技术。 相似文献
132.
汶川地震重灾区泥石流沟内崩滑物空间分布的RS-GIS定量方法 总被引:1,自引:0,他引:1
汶川地震在山区引发大量崩塌、滑坡,形成大量的固体松散碎屑物质堆积在沟谷内(CLCAR,崩滑碎屑区),使得地震山区泥石流活动性增强。以岷江上游四川省汶川县银杏乡、映秀镇的15条泥石流沟的SPOT遥感影像为基础,利用GIS技术对CLCAR空间分布进行分析。建立CLCAR与流域高程、主沟侧距和沟口纵距的分布函数T(x)、M(x)和G(x),对CLCAR的空间分布特征进行描述;并计算其积分(DT、DM和DG)作为CLCAR空间分布特征的定量化参数。结果表明,函数T(x)、M(x)和G(x)能够较全面描述CLCAR的空间分布特征,DT、DM和DG能够作为CLCAR空间分布特征的定量化参数。泥石流沟谷内CLCAR的空间分布对泥石流的形成及规模具有一定的影响;在对灾区泥石流研究时有必要考虑泥石流沟内CLCAR空间分布特征。 相似文献
133.
Landslides are an increasing problem in Nepal’s Middle Hills due to both natural and human phenomena: mainly increasingly intense monsoon rains and a boom in rural road construction. This problem has largely been neglected due to underreporting of losses and the dispersed nature of landslides. Understanding how populations cope with landslides is a first step toward developing more effective landslide risk management programs. The present research focuses on two villages in Central-Eastern Nepal, both affected by active landslides but with different coping strategies. Research methods are interdisciplinary, based on a geological assessment of landslide risk and a socio-economic study of the villages using household questionnaires, focus group discussions and transect walks. Community risk maps are compared with geological landslide risk maps to better understand and communicate community risk perceptions, priorities and coping strategies. A modified typology of coping strategies is presented, based on previous work by Burton, Kates, and White (1993) that is useful for decision-makers for designing more effective programs for landslide mitigation. Main findings underscore that coping strategies, mainly seeking external assistance and outmigration, are closely linked to access to resources, ethnicity/social status and levels of community organization. Conclusions include the importance of investing in organizational skills, while building on local knowledge about landslide mitigation for reducing landslide risk. There is great potential to increase coping strategies by incorporating skills training on landslide mitigation in existing agricultural outreach and community forest user group training. 相似文献
134.
To begin exploring the underlying mechanisms that couple vegetation to cloud formation processes, we derive the lifting condensation
level (LCL) to estimate cumulus cloud base height. Using a fully coupled land–ocean–atmosphere general circulation model (HadCM3LC),
we investigate Amazonian forest feedbacks on cloud formation over three geological periods; modern-day (a.d. 1970–1990), the last glacial maximum (LGM; 21 kya), and under a future climate scenario (IS92a; a.d. 2070–2090). Results indicate that for both past and future climate scenarios, LCL is higher relative to modern-day. Statistical
analyses indicate that the 800 m increase in LCL during the LGM is related primarily to the drier atmosphere promoted by lower
tropical sea surface temperatures. In contrast, the predicted 1,000 m increase in LCL in the future scenario is the result
of a large increase in surface temperature and reduced vegetation cover. 相似文献
135.
《地震研究进展(英文)》2021,1(3):100031
In order to study the overall deformation of geotechnical model conveniently, the worksite of landslide bridge foundation reinforced by the front and rear row anti-slide piles in Chenglan railway was taken as an example. On the basis of shaking tabe test of a 1/40 reduced scale model, the landslide deformation caused by vibration waves was monitored through burying self-made phosphor bronze strips in soil. Combined with the horizontal and vertical coordinates of the bending strain points on the phosphor bronze strips, the digital matrix was converted by applying Renka Cline random matrix generation method, and the two-dimensional contour plots were drawn based on it. The results showed that the two-dimensional contour plots reflected the basic law of landslide deformation reasonably, and it revealed the evolution process of landslide deformation and failure. The research conclusions were consistent with the test phenomenon, which met the basic requirements of overall deformation analysis of landslide model. This proposed method can monitor multiple cross sections and was practical for model test. 相似文献
136.
《地震研究进展(英文)》2021,1(3):100059
At present, substantial scientific research achievements have been made in the research on landslide occurrence, movement mechanism, mitigation measures, and structural stability during tunnel excavation. However, the interaction mechanism of a tunnel under-traversing a slope body with potential landslides is still not well understood. Based on the field data provided by previous investigations in the study area, six sets of 1:100 laboratory experiment model tests were conducted to study the stability of the landslide-prone zone of the slope body with an under-traversing tunnel. The selected distances between the tunnel and the sliding surface are 1.5, 3, and 5 times of the tunnel diameter, respectively. The experiment results show the interaction between the landslide-prone zone and the tunnel, elucidating the effect of potential landslides during the tunnel excavation process and the reaction of the landslide slip on the tunnel structure. Several conclusions are obtained: ① During the process of tunnel excavation, the vertical displacement of the tunnel vault decreases with the increase of the buried depth. ② The vertical displacement of the sliding surface increases with the increase of the buried depth of the tunnel. The horizontal displacement of sliding surface decreases with the increase of the buried depth. ③ After the occurrence of a rainfall-induced landslide, the vertical displacement of the tunnel vault in the 1.5-diameter-distance case is 57.29% greater than that in the 3.0-dismeter-distance case.④ For a two-cave tunnel, it is suggested that the cave farther from the landslide toe should be firstly excavated since it may generate less structural deformation. 相似文献
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140.
A modified approach for semi-quantitative estimation of physical vulnerability of buildings exposed to different landslide intensity scenarios 总被引:1,自引:0,他引:1
Aditi Singh Shilpa Pal 《Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards》2019,13(1):66-81
Landslides are the most common natural disasters in mountainous regions, being responsible for significant loss of life as well as damage to critical infrastructure and properties. As the world population grows, people tend to move to higher locations to construct buildings, thereby making structures vulnerable due to landslides. This paper discusses previous research on the vulnerability assessment of structures exposed to landslides and presents a modified semi-quantitative approach to assess the scenario-based physical vulnerability of buildings based on their resistance ability and landslide intensity. Resistance ability is determined by integrating expert knowledge-based resistance factors assigned to five primary building parameters. Landslide intensity matrix defining different intensity levels is proposed based on combinations of landslide velocity and volume. Physical vulnerability of buildings is estimated and classified as class I, II or III for scenario-based low to very high landslide intensity. Finally, the application of the model is illustrated with a case study of 71 buildings from Garhwal Himalayas, India. 相似文献