• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.595-598
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• 2007

Urban storm water collection and conveyance systems are critical components of the urban infrastructures. During a storm event, street grate inlets are usually loaded with debris by the first-flush runoff volume. Grate inlets are subject to clogging effects. Effective interception area of grate inlets was decreased by clogging. It also decreased the interception capacity of grate inlets and increased the inundation area in street. Therefore, it is necessary to analyze the clogging characteristics and interception capacity change by clogging for appropriate design and management of grate inlets. In this study, field survey was executed to investigate debris and clogging pattern of grate inlet in 9 areas. The clogging factor with consideration of urban area characteristics was estimated with the field survey results.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.775-778
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• 2008

In general, forecast tsunami heights announced for tsunami warning are computed by using a linear tsunami model with coarse grids which leads the underestimation of inundation area. Thus, an accurate tsunami inundation map corresponding to the forecast tsunami height is indispensible for an emergency evacuation plan. A practical way to construct a relatively accurate tsunami inundation map was proposed in this study for the quantitative forecast of inundation area. This procedure can be introduced as in the followings: The fault dislocations of potential tsunami sources generating a specific tsunami height near an interested area are found by using a linear tsunami model. Based on these fault dislocations, maximum inundation envelops of the interested area are computed and illustrated by using nonlinear inundation numerical model. In this study, the tsunami inundation map for Imwon area was constructed according to 11 potential tsunami sources, and the validity of this process was examined.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.4
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• pp.389-395
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• 2014

This technical note describes about the base stages of technology implementation for establishing "Early Warning System for Weather Hazard Management in Climate-smart Agriculture" to national onsite service. First of all, a special weather report service at catchment was represented sequential risk of 810 units of catchment by spatial statistical methods to existing 150 counties units special weather report released in KMA. The second, chronic hazard alarm service based on daily data of 76 Synoptic stations was monitor about 810 Catchment of mid-long term lapse weather and represented as a relative risk index chronic hazard risk of this time in preparation for the climatological normal conditions in the same period. Finally, we establish the foundation for delivering individually calculated field specific in hazard risk about volunteer farmer of early warning service demonstration area in seomjin downstream watershed. These three types of information were built a near real-time map service on the VWORLD background map of Ministry of Land as superposed layers nationwide catchment and demonstration areas within the farm unit weather hazard.

• Journal of the Korean Institute of Gas
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• v.16 no.1
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• pp.15-21
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• 2012

An analysis was completed of the hazards distance of hydrogen accidents such as jet release, jet fire, and vapor cloud explosion(VCE) of hydrogen gas, and simplified equations have been proposed to predict the hazard distances to set up safety distance by the gas dispersion, fire, and explosion following hydrogen gas release. For a small release rate of hydrogen gas, such as from a pine-hole, the hazard distance from jet dispersion is longer than that from jet fire. The hazard distance is directly proportional to the pressure raised to a half power and to the diameter of hole and up to several tens meters. For a large release rate, such as from full bore rupture of a pipeline or a large hole of storage vessel, the hazard distance from a large jet fire is longer than that from unconfined vapor cloud explosion. The hazard distance from the fire may be up to several hundred meters. Hydrogen filling station in urban area is difficult to compliance with the safety distance criterion, if the accident scenario of large hydrogen gas release is basis for setting up the safety distance, which is minimum separation distance between the station and building. Therefore, the accident of large hydrogen gas release must be prevented by using safety devices and the safety distance may be set based on the small release rate of hydrogen gas. But if there are any possibility of large release, populated building, such as school, hospital etc, should be separated several hundred meters.

• Journal of the Korean Association of Geographic Information Studies
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• v.10 no.3
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• pp.1-12
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• 2007

This study was conducted in order to analyze a flooded area by the overflow of a stream using hydrological and hydraulic models and to estimate the utility of the SAR satellite image by comparing a protected lowland inundation area with a past inundation area map. The research area selected for this study is Sapkyocheon, which was flooded in August 1999. The flood stage was analyzed to select an inundation area by applying flood events in August 1999. By importing analyzed flood stage data into TIN data of WMS, the inundation area of a protected lowland was selected and then compared with an flood hazard map of WAMIS. An inundation area is selected by the SAR satellite image in comparing the image of August 4, 1999 (inundation time) with the image of September 8, 2002 (after inundation). The method of selecting an inundation area with the hydraulic model of HEC-RAS can be used to select an inundation area of external overflow, but it has the limit of selecting an inundation area concerning the internal drainage. The method of using the SAR satellite image can complement the limit of an inundation area of an internal drainage but accuracy of inundation area depends on using SAR satellite image acquired at time of maximum depth.

• Journal of Preventive Medicine and Public Health
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• v.43 no.2
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• pp.166-173
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• 2010

Objectives: On December 7, 2007, the Hebei Spirit oil tanker spilled out 12,547 kl of crude oil on the Yellow Sea 10 km away from the cost of Taean Province, Korea. As the coastline has been contaminated, local residents have been exposed to crude oil. Because the residents were showing many symptoms, we investigated the acute health effects of this oil spill on them. Methods: We conducted a cross-sectional study consisting of the heavy and moderately oil soaked area in Taean and the lightly oil soaked area in Seocheon. Ten seashore villages were selected from each area, and 10 male and female adults were selected from each village. We interviewed the subjects using a structured questionnaire on the characteristics of residents, the cleanup activities, the perception of oil hazard, depression and anxiety, and the physical symptoms. The odds ratios and 95% confidence intervals were analyzed using logistic regression analysis. The logistic regression model was adjusted for age, gender, education, smoking, the perception of oil hazard and anxiousness. Results: The more highly contaminated the area, the more likely it was for residents to be engaged in cleanup activities and have a greater chance of exposure to oil. The indexes of anxiety and depression were higher in the heavy and moderately oil soaked areas. The increased risks of headache, nausea, dizziness, fatigue, tingling of limb, hot flushing, sore throat, cough, runny nose, shortness of breath, itchy skin, rash, and sore eyes were significant. Conclusions: The results suggest that exposure to crude oil is associated with various acute physical symptoms. Long-term investigation is required to monitor the residents' health.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.4
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• pp.59-66
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• 2007

The bridge crossing river is the one of the major factors causing backwater level rising. Furthermore, the bridges in the mountainous areas increase the flood damage in the upstream of the bridge due to the blockage by debris. In this research, the effects of debris to the magnitude of flood damage in the study river basin were simulated by using HEC-RAS and HEC-GeoRAS models. With assumption that the backwater caused by debris blocking the space between bridge piers is the only factor causing inundation, the unsteady flow simulation was carried out with various case studies. The potential inundation area with the overflow locations and volumes could be estimated as the results of simulation. However, the simulation results also reveal the limitations of inaccurate estimation of inundation area and depth. To overcome these hindrances, DEM and satellite images were applied to the simulation. By readjusting the inundation area using digital maps and satellite images and calibrating overflow volume and depth using DEM, the accuracy of simulation could be increased resulting more accurate flood damage estimation.

• Journal of the Korean Society of Hazard Mitigation
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• v.2 no.3 s.6
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• pp.109-117
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• 2002

An analysis to allocate storage space for sediment accumulation during the economic life of the reservoir is required in the planning or design of a reservoir. This analysis has been the most difficult and tedious aspect to deal with reservoir sedimentation because of the interaction between the various parameters related to the hydraulics of flow, reservoir operating policy, inflowing sediment load. The approach to analyzing spatial distribution of deposits has relied on empirical methods, all of which required a great deal of simplification from the actual physical phenomena. For the purpose of this study, reservoir sedimentation rate computed by Empirical Area Reduction Method is compared with measuring rate along the Soyang-gang Dam. As a conclusion, reservoir sedimentation rate can be estimated exactly by Empirical Area Reduction Method.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.3
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• pp.71-75
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• 2010

In this study, we have assessed the fire risk of Buddhist temples located in Youngdong area by means of fire loads of components. First, we categorized the components into Buddhist temples (Dae-Ung-Jeon, Pal-Sang-Jeon), Sam-Seong-Gak (Chil-Seong-Gak, San-Sin-Gak), a Buddhist temple dormitory (Sim-Geom-Dang, Seol-Seon-Dang), Lu, Il-Ju-Mun and then carried out a field survey. Then, we examined the area of each room, types as well as quantity and dimension of combustibles. The fire loads calculated in this way were 446.96 $kg/m^2$ for Buddhist temples, 331.71 $kg/m^2$ for Sam-Seong-Gak, 164.14 $kg/m^2$ for the Buddhist temple dormitory, 463.91 $kg/m^2$ for Lu and 1042.14 $kg/m^2$ for Il-Ju-Mun, thus showing Il-Ju-Mun with the biggest fire load. We speculate that this is because construction materials were similar in size and quantity to others albeit the area of Il-Ju-Mun is smallest.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.5
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• pp.67-73
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• 2010

Relatively high density of population and buildings exists in urban area mainly because of broad job opportunities and conveniences available. In other words, if happened, there might be high possibility of disaster which can not be easily recovered. The purpose of this study is to show evaluation approach of the risk degree resulted from the disaster, which considers the attributes of urban area. Cheongju-city in Chungcheongbuk-do is selected as sample district to be estimated. The degree of overall risk including fire risk, building collapse risk, evacuation risk and gas explosion risk etc. is analyzed in the designated area. The analysis suggests the highest risk degree in Bukmun-ro district which also shows CBD decline phenomenon. Therefore, it can be not only predicted that this area as old downtown has not been provided with disaster prevention operation and urban renewal project, but also judged that administrative assistances for the disaster are required possibly soon.