• Earthquakes and Structures
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• v.2 no.1
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• pp.25-42
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• 2011

This paper discusses a mechanical model for the vulnerability assessment of old masonry building aggregates that takes into account the uncertainties inherent to the building parameters, to the seismic demand and to the model error. The structural capacity is represented as an analytical function of a selected number of geometrical and mechanical parameters. Applying a suitable procedure for the uncertainty propagation, the statistical moments of the capacity curve are obtained as a function of the statistical moments of the input parameters, showing the role of each one in the overall capacity definition. The seismic demand is represented by response spectra; vulnerability analysis is carried out with respect to a certain number of random limit states. Fragility curves are derived taking into account the uncertainties of each quantity involved.

• Journal of Climate Change Research
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• v.5 no.2
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• pp.165-178
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• 2014

National and local governmental adaptation plan for climate change will become mandatory in 2015. In order to establish the plan, assessment of vulnerability to climate change needs to be preceded. LCCGIS, a toolkit for vulnerability assessment, has been widely used by many local governments. However, assessment results by LCCGIS are not yet reliable because most of the vulnerability indices applied to LCCGIS　have the same value for almost all administrative units in Korea. In this study, proxy variables for hard-collectable indices were introduced, and the results were compared with those without any proxy variables. Vulnerability assessment could be conducted subjectively due to uncertainty. Thus, determination of objective indices, understanding the available data, and changes of indices in local conditions were organized. Results from this study are expected to make vulnerability assessment reliable and contribute to assessing vulnerability to climate change reflecting on local governmental characteristics.

• Structural Engineering and Mechanics
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• v.64 no.2
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• pp.213-223
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• 2017

Bridges are lifeline and integral components of transportation system that are susceptible to seismic actions, their vulnerability assessment is essential for seismic risk assessment and mitigation. The vulnerability assessment of bridges common in Pakistan is very important as it is seismically very active region and the available code for the seismic design of bridges is obsolete. This research presents seismic vulnerability assessment of three real case simply supported multi-span reinforced concrete bridges commonly found in northern Pakistan, having one, two and three bents with circular piers. The vulnerability assessment is carried through the non-linear dynamic time history analyses for the derivation of fragility curves. Finite element based numerical models of the bridges were developed in MIDAS CIVIL (2015) and analyzed through with non-linear dynamic and incremental dynamic analyses, using a suite of bridge-specific natural spectrum compatible ground motion records. Seismic responses of shear key, bearing pad, expansion joint and pier components of each bridges were recorded during analysis and retrieved for performance based analysis. Fragility curves were developed for the bearing pads, shear key, expansion joint and pier of the bridges that first reach ultimate limit state. Dynamic analysis and the derived fragility curves show that ultimate limit state of bearing pads, shear keys and expansion joints of the bridges exceed first, followed by the piers ultimate limit state for all the three bridges. Mean collapse capacities computed for all the components indicated that bearing pads, expansion joints, and shear keys exceed the ultimate limit state at lowest seismic intensities.

• Journal of Environmental Impact Assessment
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• v.18 no.6
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• pp.347-357
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• 2009

This study conducted a vulnerability assessment on Korea's physical infrastructure to provide base data for developing strategies to strengthen Korea's ability to adapt to climate change. The assessment was conducted by surveying professionals in the field of infrastructure and climate change science. A vulnerability assessment was carried out for seven climate change events: average temperature increases, sea level rise, typhoons and storm surges, floods and heavy rain, drought, severe cold, and heat waves. The survey asked respondents questions with respect to the consequences of each climate change event, the urgency of adaptation to climate change, and the scale of investment for adaptation to each climate change event. Thereafter, management priorities for infrastructure were devised and implications for policy development were suggested. The results showed that respondents expected the possibility of "typhoons and storm surges" and "floods and heavy rain" to be the most high. Respondents indicated that infrastructure related to water, transportation, and the built environment were more vulnerable to climate change. The most vulnerable facilities included river related facilities such as dams and riverbanks in the "water" category and seaports and roads in the "transport and communication" category. The results found were consistent with the history of natural disasters in Korea.

• Structural Engineering and Mechanics
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• v.43 no.1
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• pp.127-145
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• 2012

One of the most important and challenging steps in seismic vulnerability and performance assessment of highway bridges is the determination of the bridge component damage parameters and their corresponding limit states. These parameters are very essential for defining bridge damage state as well as determining the performance of highway bridges under a seismic event. Therefore, realistic damage limit states are required in the development of reliable fragility curves, which are employed in the seismic risk assessment packages for mitigation purposes. In this article, qualitative damage assessment criteria for ordinary highway bridges are taken into account considering the critical bridge components in terms of proper engineering demand parameters (EDPs). Seismic damage of bridges is strongly related to the deformation of bridge components as well as member internal forces imposed due to seismic actions. A simple approach is proposed for determining the acceptance criteria and damage limit states for use in seismic performance and vulnerability assessment of ordinary highway bridges in Turkey constructed after the 1990s. Physical damage of bridge components is represented by three damage limit states: serviceability, damage control, and collapse prevention. Inelastic deformation and shear force demand of the bent components (column and cap beam), and superstructure displacement are the most common causes for the seismic damage of the highway bridges. Each damage limit state is quantified with respect to the EDPs: i.e. curvature and shear force demand of RC bent components and superstructure relative displacement.

• Journal of Korea Water Resources Association
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• v.48 no.8
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• pp.647-657
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• 2015

This study assessed the water use vulnerability for 12 basins of South Korea. The annual runoff of 12 basins are derived using a Soil and Water Assessment Tool (SWAT) and the calculated runoff per unit area and population are compared with each basin. The 18 indicators are selected in order to assess the vulnerability. Those are classified by aspects of demand, loss and supply of water use. Their weighting values used Entropy method to determine objective weights. To quantitatively assess the water use vulnerability, the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) based on multi-criteria decision making are applied. The results show that the water availability vulnerability of Hyeongsan River has the highest value followed by Sapgyo River; Dongjin River; Seomjin River; Anseong River; Mangyung River; Nakdong River; Tamjin River; Youngsan River, Geum River; Taehwa River; and Han River. The result of this study has a capability to provide references for the index deveopment of climate change vulnerability assessment.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.4
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• pp.129-143
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• 2014

The purpose of this study is to evaluate flooding vulnerability considering spatial characteristics focused on Changwon-si, Gyeongsangnam-do. Assessment Factors are water cycle area ratio, surface runoff, and precipitation. And construction of assessment factors and vulnerability was analyzed by GIS program. Water cycle ratio and surface runoff were vulnerable in urban area. Precipitation was often distributed in agriculture of the northern region. Results of flooding vulnerability were low in agriculture and forest of the northern region. In contrast, urban area was high because there has covered impervious land cover. Analytical results of flooding vulnerability density using hotspot spatial cluster analysis were high in urban area. And these areas were situated in down stream so flooding were generated. Therefore, flooding vulnerability assessment of this study can help for selecting construction sites of pervious land cover and rainwater management facilities in urban and environmental planning.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.22 no.5
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• pp.1079-1090
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• 2012

As the number of information asset and their vulnerabilities are increasing, it becomes more difficult for network security administrators to assess security vulnerability of their system and network. There are several researches for vulnerability analysis based on quantitative approach. However, most of them are based on experts' subjective evaluation or they require a lot of manual input for deriving quantitative assessment results. In this paper, we propose HRMS(Hacking and Response Measurement System) for enumerating attack path using automated vulnerability measurement automatically. HRMS can estimate exploitability of systems or applications based on their known vulnerability assessment metric, and enumerate attack path even though system, network and application's information are not fully given for vulnerability assessment. With this proposed method, system administrators can do proactive security vulnerability assessment.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.6
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• pp.39-44
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• 2012

Water supply capacity and operational capability in agricultural reservoirs are expressed differently in the limited storage due to seasonal and local variation of precipitation. Since agricultural water supply and demand basically assumes the uncertainty of hydrological phenomena, it is necessary to improve probabilistic approach for potential risk assessment of water supply capacity in reservoir for enhanced operational storage management. Here, it was introduced the irrigation vulnerability characteristic curves to represent the water supply capacity corresponding to probability distribution of the water demand from the paddy field and water supply in agricultural reservoir. Irrigation vulnerability probability was formulated using reliability analysis method based on water supply and demand probability distribution. The lower duration of irrigation vulnerability probability defined as the time period requiring intensive water management, and it will be considered to assessment tools as a risk mitigated water supply planning in decision making with a limited reservoir storage.

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.194-194
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• 2017