• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.2001-2005
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• 2006

우리나라는 매년 집중호우로 인한 산사태로 인해 인적, 물질적 피해를 일으킨다. 반복적인 산사태의 피해를 방지 하기위해서는 산사태 예측 시스템이 필요하다. 본 연구에서는 안성시를 대상으로 GIS와 RS 자료를 활용하여 산사태 위험지를 분석하고자 Logistic 회귀분석 방법과 AHP 기법을 이용하였다. Logistic 회귀분석과 AHP 기법에는 6개의 인자(경사, 경사향, 고도, 토양배수, 토심, 토지이용)를 사용하여, 7등급으로 산사태 위험도를 분류하였다. Logistic 회귀분석 방법과 AHP 기법을 이용한 산사태 위험지도를 표본 자료와 비교하면 산사태가 발생한 표본에서 산사태 위험성이 높은(1-2등급)지역이 Logistic 회귀분석에서는 46.1% AHP 기법은 48.7%로 분류되어 AHP 기법이 분류도가 높다고 분석 되었다. 하지만 Logistic 회귀분석과 AHP 기법은 서로 분석 과정의 차이를 가지고 있기 때문에 Logistic 회귀분석과 AHP기법을 적용한 결과에 동일 가중치를 부여한 후 7개 등급으로 재분류(reclass)하여 산사태 위험지역을 추출 할 수 있는 방법론을 제시하였다. 그 결과 산사태가 발생한 표본에서 1-2등급지역이 58.9%로 분석되어 분류정확도를 높일 수 있었다.

• Journal of Korean Society of Forest Science
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• v.97 no.3
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• pp.332-339
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• 2008

This study was carried out to develop the score table for prediction of landslide hazard in Gyeongsangbuk-Do province. It was studied to 172 places landslided in 23 cities and counties of Gyeongsangbuk-Do province. An analyze of the score table for landslide hazard was carried out through the multiple statistics of quantification method (I) by the computer. Factors effected to landslide occurrence quantity were shown in order of slope position, slope length, bedrock, aspect, forest age, slope form and slope. As results of the development of score table for prediction of landslide hazard in Gyeongsangbuk-Do province, total score range was divided that 107 under is stable area (IV class), 107~176 is area with little susceptibility to landslide (III class), 177~246 is area with moderate susceptibility to landslide (II class), above 247 area with severe susceptibility to landslide (I class).

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.2
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• pp.7-21
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• 2008

Foundation failure due to bridge scour during floods is the leading cause of bridge failure. Performed were the evaluation of bridge scour vulnerability and prioritization on real bridges registered in the National Highway Bridge Inventory of the capital region. The case studies for 30 national highway bridges consist of site investigation including boring test, bridge scour analysis fur the design flood, bearing capacity evaluation of the bridge foundation before and after scour, comprehensive evaluation of bridge scour vulnerability, and prioritization. Nine of 26 spread (feting bridges showed the potential future vulnerability to scour with significant decrease in the bearing capacity of foundations due to scour and the remaining 17 spread footing bridges were expected to maintain their stability to resist the effects of scour. Three of 4 pile foundation bridges exhibited considerable decrease in the bearing capacity of foundation after scour.

• Fire Science and Engineering
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• v.26 no.2
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• pp.1-10
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• 2012

While a performance based sprinkler design method has been widely used in UK and USA according to fire hazards of occupancies, Korean fire safety industry could not yet accept it due to nonstandardization on risk level of various occupancy. Even only two or three spray pattern sprinkler was produced in Korea fire safety industry, therefore, various spray pattern sprinklers have not yet introduced to major occupancies. Spray pattern sprinklers with one of two K value have been used in all occupancies in Korea Market. UK and USA's Fire industry should produced the spray sprinklers with various K-factors and protection area due to performance based sprinkler design requirement. Therefore the fire load density for main occupancies has been investigated in order to compare with installation standard in advanced countries. Eventually a lot of variations in orifice and K factors of standard heads were set up including special heads needed for high hazard areas such as large drop type, enlarged orifice type and early suppression fast response.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.6
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• pp.809-818
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• 2018

In this paper, in order to evaluate the impact of future climate change in North Korea, we collected the climate data of each station in North Korea provided by WMO and expanded the lack of time series data. Using the RCP climate change scenario, And the impact of climate change on disasters using local vulnerability to disasters in the event of a disaster. In order to evaluate this, the 11 cities in North Korea were evaluated for Design Rainfall Load, human risk index (HRI), and disaster impact index (DII) at each stage. As a result, Jaffe increased from C grade to B grade in the Future 1 period. At Future 2, North Hwanghae proved to be dangerous as it was, and Gangwon-do and Hwanghae-do provincial grade rose to C grade. In the case of Future 3, Pyongyang City dropped from C grade to D grade, Hamgyong and Gyeongsang City descend from B grade to C grade, Gangwon-do and Jagangdo descend from C grade to D grade and Pyongyang city descend from C grade to D grade. Respectively.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.5
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• pp.9-17
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• 2016

Vehicle collision to bridges has been known as one of the causes of bridge collapse, and the emergency plans and disaster management has been recently emphasized to secure public safety. This study conducted risk assessment of vehicular collision to bridges for highway bridges in Korea. Risk assessment consists of three steps; preliminary risk analysis(PRA), simplified risk analysis(SRA) and detailed risk analysis(DRA). The PRA firstly screens out the possibility of occurrence of the event. The SRA identifies influencial factors to risk of the event and evaluates risk scores to determine risk levels and necessity of DRA that investigates the risk of the bridge in detail. This study focuses on the methodology of the risk assessment, especially the SRA, and the stratification methods which evaluate risk levels of vehicular collision. The analysis results were compared to the reported vehicular collision accidents. The proposed method can be utilized in similar disaster management area.

• Applied Chemistry for Engineering
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• v.35 no.1
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• pp.29-36
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• 2024

The fire risk and fire safety of four types of wood were comprehensively evaluated according to Chung's equation-XII. White ash, willow, fraxinus mandshurica, and sagent cherry trees were selected as test specimens. A cone calorimetery (ISO 5660-1) was used to examine the combustion characteristics of the test piece, and finally, the fire risk rating (FRR) was predicted using the fire risk index-XII (FRI-XII). The predicted fire performance index-X (FPI-X) and fire growth index-X (FGI-X) ranged from 469.03 to 1109.73 s²/kW and 0.0009 to 0.0280 kW/s², respectively. Additionally, the fire performance index-XI (FPI-XI) and fire growth index-XI (FGI-XI) ranged from 0.41 to 0.97 and 1.11 to 3.11, respectively. The fire risk index-XII (FRI-XII), representing a fire risk rating, showed that the fire risk of frasxinus mandsurica tree (FM) was very high at 7.60 (fire risk rating: D). And it was compared with Chung's equation-IX, fire risk index-IX (FRI-IX). The fire risk ratings according to FRI-IX and FRI-XII were generally high for willow and frasxinus mandsurica trees. Additionally, the results of FRI-XII and FRI-IX had a similar relationship, and the size of each fire safety rating closely matched each other.

• Journal of Korean Society of societal Security
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• v.4 no.2
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• pp.29-40
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• 2011

The objective of this paper is to develop an intelligent decision support system that is able to advise disaster countermeasures and degree of incidents on the basis of the collected and analyzed signs of disasters. The concepts derived from ontology, text mining and case-based reasoning are adapted to design the system. The functions of this system include term-document matrix, frequency normalization, confidency, association rules, and criteria for judgment. The collected qualitative data from signs of new incidents are processed by those functions and are finally compared and reasoned to past similar disaster cases. The system provides the varying degrees of how dangerous the new signs of disasters are and the few countermeasures to the disaster for the manager of disaster management. The system will be helpful for the decision-maker to make a judgment about how much dangerous the signs of disaster are and to carry out specific kinds of countermeasures on the disaster in advance. As a result, the disaster will be prevented.

• The Journal of the Korea Contents Association
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• v.16 no.3
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• pp.81-90
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• 2016

This study aims to investigate the association between stock performance and credit ratings, and credit rating changes using a sample of 1,691 KRX firm-years that acquire equity in the form of long-term bonds from 2002 to 2013. Previous U.S. literature is mixed with regard to the relation between credit ratings and stock price. On one hand, there is evidence of a positive relation between credit ratings and stock prices, an anomaly established in U.S. studies. On the other hand, the CAPM model suggests a negative relation between stock prices and credit ratings, implying that investors expect financial rewards for bearing additional risk. To our knowledge, we are the first to examine the relationship between stock price and default risk proxied by credit ratings in period t+1. We find a negative (positive) relation between credit ratings (risk) in period t+1 and stock returns in period t, suggesting that credit rating agencies do not consider stock returns as a metric with the potential to influence default risk. Our results suggest that market participants may prefer firms with higher credit risk because of expected higher returns.

• Spatial Information Research
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• v.17 no.3
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• pp.261-268
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• 2009

This study accomplished to draw a soil erosion map and a grade map of soil loss hazard in Korea. RUSLE and Rainfall-runoff (R) factor, which was estimated by using the rainfall data observed in 59 meteorological stations from 1977 to 2006 (for 30 years). FARD was used to analyze the frequency, and the whole country R factor was estimated according to the frequency. In the analysis of estimating the whole country R factor, Nakdong river has the smallest vaule, but Han river has the biggest value. According to the result of analyzing soil loss, soil loss occurred in a grass land, a bare land and a field in size order, and also approximately 17.2 ton/ha soil loss happened on the whole area. The average soil loss amount by the unit area takes place in a bare land and a grass land a lot. The total amount of soil loss in 5-year-frequency rainfall yields 15,000 ton and, what is more, a lot of soil loss happens in a paddy field, a forest and a crop field. The grade map of soil loss hazard is drawn up by classifying soil loss hazard grade by 5. As a result of analyzing soil loss, the moderate area which is the soil loss hazard grade 2 takes up the largest part, 72.8% of the total soil loss hazard area, on the contrary, the severe soil loss hazard area takes up only $1,038km^2$ (1.1%) of the whole area. The severe soil loss hazard area by land cover shows $93.5km^2$ in a bare land, $168.1km^2$ in a grass land and $327.4km^2$ in a crop field respectively.