• Journal of the Korean Geotechnical Society
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• v.34 no.6
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• pp.25-36
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• 2018

Soil liquefaction is one of the types of major seismic damage. Soil liquefaction is a phenomenon that can cause enormous human and economic damages, and it must be examined before designing geotechnical structures. In this study, we proposed a practical method of developing a multi-hazard fragility surface for liquefaction of levee considering earthquake magnitude and water level. Limit state for liquefaction of levee was defined by liquefaction potential index (LPI), which is frequently used to assess the liquefaction susceptibility of soils. In order to consider the uncertainty of soil properties, Monte Carlo Simulation based probabilistic analysis was performed. Based on the analysis results, a 3D fragility surface representing the probability of failure by soil liquefaction as a function of the ground motion and water level has been established. The prepared multi-hazard fragility surface can be used to evaluate the safety of levees against liquefaction and to assess the risk in earthquake and flood prone areas.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09a
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• pp.66-67
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• 2005

• Journal of the Korean Society of Safety
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• v.9 no.1
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• pp.95-99
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• 1994

Recently, there has been considerable concern about waste water discharges of chromium. The Chromium(IV) is of particular concern because this form has been demonstrated to be public health hazard. Chromium(IV) could be removed by the method of electrolysis from plating waste water. It was found that almost all of chromium(IV) present could be treated by electrolysis at current, 3A and pH 8.

• 한국방재학회:학술대회논문집
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• 2009.02b
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• pp.156.1-156.1
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• 2009

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.2
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• pp.111-122
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• 2010

As the Jamsu-bridge and the floodplains of the Han River can be flooded during the rainy season, the exact prediction of the peak flood time is very important for mitigation of flood hazard. This study analyzes the effect of outflow of Paldang Dam and tide of Yellow Sea on the Han River. A target area is from the Paldang dam to Jeonryu gauging station. Water level of Jeonryu as a downstream boundary condition was estimated through multi linear regression analysis with outflow of Paldang dam and tide level of Incheon, because it was influenced by both a tide of Yellow Sea and outflow of Paldang dam. In this study, Water Level Rising Travel Time of the Jamsu-bridge and some floodplains in the Han River are estimated. Also, The second order polynomial expressions for relationships of outflow of Paldang Dam and Water Level Rising Travel Time were developed considering the outflow of Paldang dam and tide of Yellow Sea.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.4
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• pp.135-144
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• 2010

Many plans of ecologic streams are developed and performed in several regions. In spite of obtaining of instream water is most important problem to composite an ecologic stream, assessment methods for instream water are too various to estimate an optimal result. This study shows practical assessment method which add regional needs such as stream view and necessary water quality level to the traditional method considering water shortage, water quality, ecologic system and necessary flows. It also shows a feasibility of instream water obtaining project in Daejeon city.

• 한국방재학회:학술대회논문집
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• 2009.02b
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• pp.124.1-124.1
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• 2009

• 한국방재학회:학술대회논문집
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• 2009.02b
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• pp.158.1-158.1
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• 2009

• Wind and Structures
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• v.31 no.4
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• pp.321-334
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• 2020

Engineering type tropical cyclone (TC) wind field models are used to estimate TC wind hazard. Some of the models are well-calibrated using observation data, while others are not extensively compared and verified. They are all proxies to the real TC wind fields. The computational effort for their use differs. In the present study, a comparison of the predicted wind fields is presented by considering three commonly used models: the gradient wind field model, slab-resolving model, and a linear height-resolving model. These models essentially predict the horizontal wind speed at a different height. The gradient wind field model and linear height-resolving model are simple to use while the nonlinear slab-resolving model is more compute-intensive. A set of factors is estimated and recommended such that the estimated TC wind hazard by using these models becomes more consistent. The use of the models, including the developed set of factors, for estimating TC wind hazard over-water and over-land is presented by considering the historical tracks for a few sites. It is shown that the annual maximum TC wind speed can be adequately modelled by the generalized extreme value distribution.

• Korean journal of food and cookery science
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• v.19 no.2
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• pp.231-240
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• 2003

The purpose of this study was to evaluate the effect of implementing the HACCP system on foodservice establishments. At first, the hygienic conditions were measured by microbiological hazard analyses of the cooking utensils and working areas. In order to solve the detected problems, the HACCP system was implemented, after what was considered a sufficient settlement period following the initial assessment, then microbiological verification was performed again. In relation to the cooking utensils and equipment(kitchen knives, cutting boards, knives for shredding vegetables, refrigerators, baskets, barts, working tables, preparation tables, tungs, dish-clothes and drains) the microbiological inspection on the Total Plate Count, Coliforms, Staphylococcus aureus and Listeria monocytogenes, were conducted with regard to the working areas(working tables, preparation tables, seasoning's shelves, serving tables, drinking water tables, refrigerators, storage rooms and dining tables), the Total Plate Count and Fungi were also examined. According to the microbiological hazard analyses there were many problems, especially with cutting boards, baskets, barts, dish-clothes and sinkballs. However, by introducing the HACCP system, the microbiological hazard levels were able to be controlled and lowered, and the total aerial bacteria in the working areas of the foodservice establishments were detected at levels below 6 CFU/plate.