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11.
Comparison of numerical models of two debris flows in the Cortina d’ Ampezzo area,Dolomites, Italy 总被引:2,自引:0,他引:2
The accurate prediction of runout distances, velocities and the knowledge of flow rheology can reduce the casualties and property
damage produced by debris flows, providing a means to delineate hazard areas, to estimate hazard intensities for input into
risk studies and to provide parameters for the design of protective measures. The application of most of models that describe
the propagation and deposition of debris flow requires detailed topography, rheological and hydrological data that are not
always available for the debris-flow hazard delineation and estimation. In the Cortina d’Ampezzo area, Eastern Dolomites,
Italy, most of the slope instabilities are represented by debris flows; 325 debris-flow prone watersheds have been mapped
in the geomorphological hazard map of this area. We compared the results of simulations of two well-documented debris flows
in the Cortina d’Ampezzo area, carried on with two different single-phase, non-Newtonian models, the one-dimensional DAN-W
and the two-dimensional FLO-2D, to test the possibility to simulate the dynamic behaviour of a debris flow with a model using
a limited range of input parameters. FLO-2D model creates a more accurate representation of the hazard area in terms of flooded
area, but the results in terms of runout distances and deposits thickness are similar to DAN-W results. Using DAN-W, the most
appropriate rheology to describe the debris-flow behaviour is the Voellmy model. When detailed topographical, rheological
and hydrological data are not available, DAN-W, which requires less detailed data, is a valuable tool to predict debris-flow
hazard. Parameters obtained through back-analysis with both models can be applied to predict hazard in other areas characterized
by similar geology, morphology and climate. 相似文献
12.
良好植被区泥石流防治初探 总被引:10,自引:0,他引:10
通过对近年来发生在良好植被区的几次重大泥石流、滑坡灾害的考察,发现植被在泥石流、滑坡形成中的作用有待于进一步认识。通过分析,当中小强度降雨激发下,植被能够削减泥石流、滑坡灾害的规模,甚至抑制泥石流、滑坡灾害的发生;当降雨超过一定阀值后,在水作用下,植被不但不能削减灾害规模,反而增大灾害的规模。在这类地区,简单地使用一般的防治措施,已经不能满足防灾、减灾的需要,客观要求针对这些地区泥石流灾害的形成原因、危害特征,研究防治对策。经初步研究提出3点防治措施:1)加强泥石流滑坡灾害的预测预报工作;2)在重点区域设置自动雨量记录报警装置;3)特别针对漂木拦挡,采取新型结构减轻泥石流的危害。 相似文献
13.
A multi-method approach to study the stability of natural slopes and landslide susceptibility mapping 总被引:8,自引:0,他引:8
In this paper, a multi-method approach for the assessment of the stability of natural slopes and landslide hazard mapping applied to the Dakar coastal region is presented. This approach is based on the effective combination of geotechnical field and laboratory works, of GIS, and of mechanical (deterministic and numerical) stability analysis. By using this approach, valuable results were gained regarding instability factors, landslide kinematics, simulation of slope failure and coastal erosion. This led to a thorough assessment and strong reduction in the subjectivity of the slope stability and hazard assessment and to the development of an objective landslide danger map of the SW coast of Dakar. Analysis of the results shows that the slides were influenced by the geotechnical properties of the soil, the weathering, the hydrogeological situation, and the erosion by waves. The landslide susceptibility assessment based on this methodological approach has allowed for an appropriate and adequate consideration of the multiple factors affecting the stability and the optimization of planning and investment for land development in the city. 相似文献
14.
The increasing natural disasters, especially floods during the last quarter century, are raising the economic losses in Taiwan.
The most severe hazard in Taiwan is flooding induced by typhoons and storms in summer and autumn. By comparing the rivers
around the world, the ones in Taiwan have the steepest slopes, the largest discharge per unit drainage area, and the shortest
time of concentrations. Rapid urbanization without proper land uses managements usually worsen the flood problems. Consequently,
flood hazards mitigation has become the most essential task for Taiwan to deal with. Although the government keeps improving
flood defense structures, the flood damage grows continuously. In this article, possible flood mitigation strategies are identified
for coping with complex environmental and social decisions with flood risk involved. 相似文献
15.
Matthew J. Spittal Frank H. Walkey John McClure Richard J. Siegert Kimberley E. Ballantyne 《Natural Hazards》2006,39(1):15-29
Preparedness is a key dependent variable in many studies examining people’s response to disasters such as earthquakes. A feature
of many studies on this issue, however, is the lack of attention given to psychometric issues when constructing measures of
preparedness. With regard to earthquake preparation, for example, many studies could be greatly improved by the use of a valid
and reliable measure of preparedness. This research developed such a measure that assessed both low-level preparedness, such
as having an emergency kit, and high-level preparedness, such as altering home structures to mitigate damage. Studies of Wellington
(New Zealand) residents using two samples totalling n=652 showed that 23 items measuring these different aspects of earthquake preparation could be combined into a reliable, valid,
unifactorial scale. This brief scale should have utility in multivariate studies of earthquake preparation, either as a dependent
variable, where preparation is the outcome variable of primary interest, or as one of several independent variables, where
preparation and other measures predict another outcome variable. 相似文献
16.
我国煤炭资源开发利用中某些问题的探讨 总被引:3,自引:0,他引:3
针对我国煤炭资源开发利用中存在的诸如煤炭资源的低效率应用、无序开采、生态环境恶化等问题,指出了我国煤炭资源管理法规中存在的问题,提出了加强煤炭资源开发管理、构建煤炭循环经济体系、加大安全投入、加强煤炭矿区环境的治理和保护、健全有偿使用资源法规制度等对策。 相似文献
17.
Midstream of the Keelung River Basin in Northern Taiwan has become highly urbanized and densely populated area. Flood inundation
along riversides frequently occurred during typhoons or rainstorms. Three protection measures, including constructions of
high-level protection levees, a diversion channel, and a detention reservoir, were proposed for flood mitigation. The main
purpose of this study is to evaluate the flood mitigation performance of the three proposed structural measures by using combined
hydrologic analyses and hydraulic routings. A semi-distributed parallel-type linear reservoirs rainfall-runoff model was used
for estimating the surface runoff. Furthermore, a 1-D dynamic channel routing model was coupled with a two-dimensional inundation
model to simulate the hydraulic characteristics of river flooding and overland flow. Simulation results of flood stages, runoff
peak discharges, and inundation extent under design rainfall scenarios were chosen as the criteria for evaluation. The results
showed a diversion channel is superior to the other two measures for flood mitigation of the study area. After the process
of environmental impact assessment, a revised diversion channel approach has been approved for construction as the major structural
measure. 相似文献
18.
现阶段地表油气化探技术难题与发展对策 总被引:2,自引:1,他引:2
虽然地表油气化探方法技术已取得显著的应用效果, 但是由于成功率计算标准不同及方法技术本身的缺陷, 导致人们对方法的认同度较低。当前, 地表油气化探技术的发展, 一方面要以可靠的实验依据、严谨的数理推导及理论模型应对来自方法技术本身的挑战, 另一方面也要利用其快速、廉价和直接的优势, 加强与地质、遥感、非震物探等方法综合应用。 相似文献
19.
列举了企业内邵会计控制存在的内部会计系统控制机制不健全,监督、考核机制乏力,财务控制存在漏洞、公司企业治理结构不完善等目前企业内部会计控制现状及重点存在问题。提出了完善企业的内部会计控制环境.不相容职务必须分离,强化监督,督促实施,加强会计基础工作,完善会计电算化管理,规范业务处理程序等具体改进建议。 相似文献
20.