• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.163-163
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• 2023

Flooding has become an increasing event which is one of the major natural disasters responsible for direct economic damage in South Korea. Driven by climate change, precipitation extremes play significant role on the flood damage and its further increase is expected to exacerbate the socioeconomic impact in the country. However, the empirical evidence associating changes in precipitation extremes to the historical flood damage is limited. Thus, there is a need to assess the causal relationship between changes in precipitation extremes and flood damage, especially in agricultural region like Chungcheong region in South Korea. The spatial and temporal changes of precipitation extremes from 10 synoptic stations based on daily precipitation data were analyzed using the ClimPACT2 tool and Mann-Kendall test. The four precipitation extreme indices consisting of consecutive wet days (CWD), number of very heavy precipitation wet days (R30 mm), maximum 1-day precipitation amount (Rx1day), and simple daily precipitation intensity (SDII), which represent changes in intensity, frequency, and duration, respectively, and the time series data on flooded area and flood damage from 1985 to 2020 were used to investigate the causal relationship in the ARDL-ECM framework and pairwise Granger causality analysis. The trend results showed that majority of the precipitation indices indicated positive trends, however, CWD showed no significant changes. ARDL-ECM framework showed that there was a long-run relationship among the variables. Further analysis on the empirical results showed that flooded area and Rx1day have significant positive impacts on the flood damage in both short and long-runs while R30 mm only indicated significant positive impact in the short-run, both in the current period, which implies that an increase in flooded area, Rx1day, and R30 mm will cause an increase in the flood damage. The pairwise Granger analysis showed unidirectional causality from the flooded area, R30 mm, Rx1day, and SDII to flood damage. Thus, these precipitation indices could be useful as indicators of pluvial flood damage in Chungcheong region of South Korea.

• Corrosion Science and Technology
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• v.21 no.2
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• pp.147-157
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• 2022

Electrochemical characteristics and damage behavior of 6061-T6 aluminum alloy used as a battery housing material for electric vehicles were investigated in solution simulating the acid rain environment with chloride concentrations. Potentiodynamic polarization test was performed to analyze electrochemical characteristics. Damage behavior was analyzed through Tafel analysis, measurement of damage area, weight loss, and surface observation. Results described that corrosion current density was increased rapidly when chloride concentration excceded 600 PPM, and it was increased about 7.7 times in the case of 1000 PPM compared with 0 PPM. Potentiodynamic polarization experiment revealed that corrosion damage area and mass loss of specimen increased with chloride concentrations. When chloride concentration was further increased, the corrosion damage area extended to the entire surface. To determine damage tendency of pitting corrosion according to chloride concentration, the ratio of damage depth to width was calculated. It was found that the damage tendency decreased with chloride concentrations. Thus, 6061-T6 aluminum alloy damage becomes larger in the width direction than in the depth direction when a small amount of chloride is contained in an acid rain environment.

• Journal of Korea Water Resources Association
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• v.47 no.8
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• pp.717-728
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• 2014

In this study, we developed a depth-damage function based on flood damage survey with focusing on building damage in urban area. We designed items for the questionnaire survey to develop a depth-damage function which estimates the amount of damage based on inundation depth targeting Dongducheon, Korea, which has experienced severe inundation damage due to significant flooding in July 2011. Based on the survey of the area, we developed a depth-damage function and used this to estimate the real amount of damage on buildings in the inundation area. To assess the damage on buildings, we categorized buildings into two groups; namely residential buildings and commercial buildings. Also, in order to calculate the real amount of damage caused by flooding, properties and detailed damaged items were sub-divided into two groups for the survey; facilities loss (wall paper, floor paper, painting, electrical facilities, and boilers) and furnishing loss (furniture, electronic products, and daily necessities. We expect this study on the process for developing depth-damage function and on the investigation research for flooded area to help in the efficient implementation of all kinds of disaster management policies and the attainment of a society safe from disaster.

• Journal of the Society of Naval Architects of Korea
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• v.55 no.3
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• pp.274-280
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• 2018

This paper deals with the calculation of vulnerable areas of critical components required for the assessment of naval ship's vulnerability. Taking into account the effectiveness of threatening weapons, the probability density function of damage was used to assess vulnerable areas or vulnerabilities of critical components. It is shown that the vulnerable area of critical component can be simply computed from the damage function. Considering the weapon effectiveness of fragmentation and explosion on the target, both Carleton Damage Function and Rectangular Cookie Cutter Function representing the probability of damage are applied to the vulnerable area assessment. Carleton damage function is utilized to describe the weapon-target interaction in the vulnerability analyses. A problem of blast effect against an assumed naval ship is chosen as a case study. Vulnerability is evaluated by applying the suggested method to the equipments arranged in the engine room of the virtual ship.

• The Korean Journal of Ecology
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• v.1 no.2
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• pp.66-71
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• 1977

The growth of red and black pines in Muan, Seochen, Gapyeong and Kochang areas was compared by means of the growth of annual ring width and stem analysis to study the process of damages caused by pine needle gall midge. Red pine forest of Seocheon area began to suffer by pine needle gall midge from 1961 and the damage was to becoming severe from 1967. The damage became so intense tha tmany forests are withering to death from spring of 1975. Black pine forest also began to suffer from 1973. Red pine forest of Muan area was supposed to be suffered from 1973. Red pine forest of Kochang area suffered by pine needle gall midge from 1967. It seems that the damage became severe from 1973 and that black pine forest was also badly damaged from that time. Red pine forest of the control plot, Gapyeong area, began to suffer from 1967 and it also became intense from 1973. Although the areas of Seocheon, Muan, Kochang, and Gapyeong are different from each other in terms of locality and the infitration period of pine needle gall equally from 1967 due to mass development of population or other factors and the damage became more intense from 1973. Black pine forest was also badly damaged from that time. Black pine seems to be stronger in insect resistant than red pine. This can be justified by the fact that it began to suffer belatedly in each area and the degree of damage is moderate. The damage of Seocheon area is the severest following Kochang. Muan area is relatively moderate but the forest becoming decrease in growth.

• Journal of the Korean Institute of Gas
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• v.7 no.4 s.21
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• pp.53-60
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• 2003

Accident occurred by gas explosion in house or building causes damage on lives and properties. To avoid secondary damage, this study drew area ratio of vent area with the experiment for pressure variation with vent area versus building volume by selection of model for different size and shapes of vent area generated by explosion. In addition, Appropriate model was chosen to predict the damage by minimum pressure with the experiment of opening are shapes. This model can prevent secondary damage with the selected vent area and shape to guarantee building safety.

• Journal of Navigation and Port Research
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• v.43 no.3
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• pp.209-218
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• 2019

Coastal cities suffer a great deal of storm and wind damage. The storm and wind characteristics vary between cities. Therefore, a storm and wind damage management system suited for specific characteristics is required for each coastal city. In this study, we analyze the current situation and establish the problem of storm and wind damage management system in regards to urban management, coastal management and disaster management. We also review the storm and wind damage management system for the USA and Japan. We consequently propose a plan to improve the storm and wind damage management system. As a result of the study, in terms of city management, we recommend the compulsory identification of disaster prevention districts, implementation of the integrated coastal city management plan, designation of natural disaster risk mitigation area as disaster prevention district, the division of disaster prevention district into wind damage prevention district, storm damage prevention district, erosion damage prevention district, the building of restrictions at the disaster prevention district by ordinance, etc. In regards to coastal management, we suggest the delegation of authority to delegate coastal erosion management area to the local government, the subdivision of coastal erosion management area into erosion serious area, erosion progress area, erosion concern area, the building restrictions at coastal erosion management area by ordinance, development of erosion prediction chart, etc. In relation to disaster management, we recommend the integration of "countermeasures against natural disasters act" and "disasters and safety management basic act", the local government-led disaster prevention system, the local disaster management network, and the customized local disaster prevention plan, etc.

• Journal of Korean Society for Atmospheric Environment
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• v.3 no.1
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• pp.47-54
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• 1987

A new method for designing air pollution monitoring newtork is presented in this study. In this method, the magnitudes and the correlation coefficients of predicted concentrations in each grid points are examined and the monitoring stations are assigned to those stations which cover the damage cost the most. This method was applied to the Ulsan-Onsan Industrial Complex. This method turned out to be much more efficient than the method of TM coordinates and the method of concentric circles prescribed in the Standard Methods for Pollution Measurement as well as the existing monitoring system established in the area. The 21 stations selected by the method of TM coordinates could cover only 64.4% of the damage cost in the area, the 16 stations by the method of concentric circles 72.1%, and the existing 21 stations 67.8%, while 11 stations were enough to cover 90% of the damage cost in the area with this method. It also was found that this method required only 24 stations to cover the entire area.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.35 no.2
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• pp.113-122
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• 2017

Natural disasters caused by climate change are increasing globally. There are few studies on the quantitative analysis methods for predicting damages in the island area due to sea level rise. Therefore, it is necessary to study the damage prediction analysis method using the GIS which can quantitatively analyze. In this paper, we analyze the cause and status of sea level rise, quantify the vulnerability index, establish an integrated terrestrial modeling method of the ocean and land, and establish a method of analyzing the damage area and damage scale due to sea level rise using GIS and the method of making the damage prediction figure was studied. In order to extract the other affected areas to sea level rise are apart of the terrain model is generated by one requires a terrain modeling of target areas are offshore and vertical reference system differences in land, found the need for correction by a tidal observations and geoid model there was. Grading of terrain, coastline erosion rate, coastal slope, sea level rise rate, and even average by vulnerable factors due to sea level rise indicates that quantitative damage prediction is possible due to sea level rise in the island area. In the case of vulnerable areas extracted by GIS, residential areas and living areas are concentrated on the coastal area due to the nature of the book area, and field survey shows that coastal changes and erosion are caused by sea level rise or tsunami.

• Earthquakes and Structures
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• v.7 no.4
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• pp.449-462
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• 2014

Seismically induced structural damage, as well as any damage caused by a natural catastrophic event, covers a wide area. This suggests to supervise the event consequences by vision tools. This paper reports the evolution from the results obtained by the project RADATT (RApid Damage Assessment Telematics Tool) funded by the European Commission within FP4. The aim was to supply a rapid and reliable damage detector/estimator for an area where a catastrophic event had occurred. Here, a general open-source methodology for the detection and the estimation of the damage caused by natural catastrophes is developed. The suitable available hazard and vulnerability data and satellite pictures covering the area of interest represent the required bits of information for updated telematics tools able to manage it. As a result the global damage is detected by the simple use of open source software. A case-study to a highly dense agglomerate of buildings is discussed in order to provide the main details of the proposed methodology.