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Within the engineering profession and natural sciences, vulnerability is widely accepted to be defined as the degree of loss
(or damage) to a given element or set of elements within the area affected by a threat. The value of vulnerability is expressed
nondimensionally between 0 and 1. It is a fundamental component in the evaluation of landslide risk, and its accurate estimation
is essential in making a reasonable prediction of the landslide consequences. Obviously, vulnerability to landslides depends
not only on the characteristics of the element(s) at risk but also on the landslide intensity. This paper summarizes previous
research on vulnerability to landslides and proposes a new quantitative model for vulnerability of structures and persons
based on landslide intensity and resistance of exposed elements. In addition, an approximate function is suggested for estimating
the vulnerability of persons in structures. Different methods for estimating the vulnerability of various elements to slow
or rapid landslides are discussed. Finally, the application of the new model is illustrated through an example. 相似文献
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Selecting the correct resolution in distributed hydrological modelling at the watershed scale is essential in reducing scale-related errors. The work presented herein uses information content (entropy) to identify the resolution which captures the essential variability, at the watershed scale, of the infiltration parameters in the Green and Ampt infiltration equation. A soil map of the Little Washita watershed in south-west Oklahoma, USA was used to investigate the effects of grid cell resolution on the distributed modelling of infiltration. Soil-derived parameters and infiltration exhibit decreased entropy as resolutions become coarser. This is reflected in a decrease in the maximum entropy value for the reclassified/derived parameters vis a vis the original data. Moreover, the entropy curve, when plotted against resolution, shows two distinct segments: a constant section where no entropy was lost with decreasing resolution and another part which is characterized by a sharp decrease in entropy after a critical resolution of 1209 m is reached. This methodology offers a technique for assessing the largest cell size that captures the spatial variability of infiltration parameters for a particular basin. A geographical information system (GIS) based rainfall-runoff model is used to simulate storm hydrographs using infiltration parameter maps at different resolutions as inputs. Model results up to the critical resolution are reproducible and errors are small. However, at resolutions beyond the critical resolution the results are erratic with large errors. A major finding of this study is that a large resolution (1209 m for this basin) yields reproducible model results. When modelling a river basin using a distributed model, the resolution (grid cell size) can drastically affect the model results and calibration. The error structure attributable to grid cell resolution using entropy as a spatial variability measure is shown. 相似文献
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Zhongqiang Liu Farrokh Nadim Alexander Garcia-Aristizabal Arnaud Mignan Kevin Fleming Byron Quan Luna 《Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards》2015,9(2):59-74
The effective management of the risks posed by natural and man-made hazards requires all relevant threats and their interactions to be considered. This paper proposes a three-level framework for multi-risk assessment that accounts for possible hazard and risk interactions. The first level is a flow chart that guides the user in deciding whether a multi-hazard and risk approach is required. The second level is a semi-quantitative approach to explore if a more detailed, quantitative assessment is needed. The third level is a detailed quantitative multi-risk analysis based on Bayesian networks. Examples that demonstrate the application of the method are presented. 相似文献
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Finn Løvholt Sylfest Glimsdal Carl B. Harbitz Natalia Zamora Farrokh Nadim Pascal Peduzzi Hy Dao Helge Smebye 《Earth》2012,110(1-4):58-73
In the aftermath of the 2004 Indian Ocean tsunami, a large increase in the activity of tsunami hazard and risk mapping is observed. Most of these are site-specific studies with detailed modelling of the run-up locally. However, fewer studies exist on the regional and global scale. Therefore, tsunamis have been omitted in previous global studies comparing different natural hazards. Here, we present a first global tsunami hazard and population exposure study. A key topic is the development of a simple and robust method for obtaining reasonable estimates of the maximum water level during tsunami inundation. This method is mainly based on plane wave linear hydrostatic transect simulations, and validation against results from a standard run-up model is given. The global hazard study is scenario based, focusing on tsunamis caused by megathrust earthquakes only, as the largest events will often contribute more to the risk than the smaller events. Tsunamis caused by non-seismic sources are omitted. Hazard maps are implemented by conducting a number of tsunami scenario simulations supplemented with findings from literature. The maps are further used to quantify the number of people exposed to tsunamis using the Landscan population data set. Because of the large geographical extents, quantifying the tsunami hazard assessment is focusing on overall trends. 相似文献
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Farhad Nadim Amvrossios C. Bagtzoglou Jamshid Iranmahboob 《Ocean & Coastal Management》2008,51(7):556-565
Persian Gulf is a semi-enclosed sea located in the Middle East and is connected to oceans through the narrow 55-km Strait of Hormuz. The Persian Gulf holds an estimated 57–66% of the world's known reserves of oil. The occurrence of three major battles in the Gulf region during the past three decades has created an atmosphere of commotion and uncertainty. Because of its marine geology, geographical location, and geopolitical sensitivity, coastal management in the Gulf region cannot be considered independently of its vast oil and natural gas reserves and environmentally related matters. The Regional Organization for Protection of Marine Environment (ROPME) forum was established in Kuwait in 1979 and quickly ratified by seven new member states (Bahrain, Iran, Iraq, Oman, Qatar, Saudi Arabia and the United Arab Emirates). Rapid growth of ROPME and shared coastal and marine environmental issues among littoral States have resulted in numerous successful plans laying the basis for future coastal management and development in the Persian Gulf region.Different plans were investigated to reach sustainable coastal management and environmental pollution prevention programmes in the Persian Gulf region and it was concluded that such plans could only be implemented when littoral states prioritize the management schemes in the Persian Gulf region and incorporate them into their own national legislation.Similar to many Regional Sea Programmes, ROPME has faced many drawbacks since its inception. Military conflicts, poor enforcement of protocols, lack of adequate coordination, disharmony among littoral states and lack of sufficient funding have put many coastal management programmes on hold.Demilitarization, enforcement of ROPME resolutions, and implementation of long-term economical growth planning are all part of an integrated coastal management programme that can bring about significant changes in the Persian Gulf area. Despite all existing differences and difficulties, many important tasks have been accomplished in the past two decades. Coastal management issues have been analyzed and well documented by ROPME. With the existing situation in the Gulf region, ROPME can effectively coordinate and implement the following tasks: monitor water quality and coastal habitat, develop and implement a comprehensive pollution prevention scheme, educate the public in terms of coastal preservation, train technical staff, put in place an effective pollution prevention and waste management programme, and establish the basis for an integrated regional coastal zone management plan. 相似文献
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A mechanism of horizontal floor response spectra amplification in the vicinity of higher modes' frequencies is investigated. It is demonstrated, by means of a simple two‐degrees‐of‐freedom model, that in the case of unsymmetrical superstructure, such amplification may occur because of the coupling between vertical excitation and horizontal response of the non‐isolated modes. This phenomenon is further illustrated by the results of analyses of a model of a nuclear plant. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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A novel methodology for the interpretation of pumping tests in leaky aquifer systems, referred to as the double inflection point (DIP) method, is presented. The method is based on the analysis of the first and second derivatives of the drawdown with respect to log time for the estimation of the flow parameters. Like commonly used analysis procedures, such as the type-curve approach developed by Walton (1962) and the inflection point method developed by Hantush (1956), the mathematical development of the DIP method is based on the assumption of homogeneity of the leaky aquifer layers. However, contrary to the two methods developed by Hantush and Walton, the new method does not need any fitting process. In homogeneous media, the two classic methods and the one proposed here provide exact results for transmissivity, storativity, and leakage factor when aquifer storage is neglected and the recharging aquifer is unperturbed. The real advantage of the DIP method comes when applying all methods independently to a test in a heterogeneous aquifer, where each method yields parameter values that are weighted differently, and thus each method provides different information about the heterogeneity distribution. Therefore, the methods are complementary and not competitive. In particular, the combination of the DIP method and Hantush method is shown to lead to the identification of contrasts between the local transmissivity in the vicinity of the well and the equivalent transmissivity of the perturbed aquifer volume. 相似文献
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