• Proceedings of the Korea Water Resources Association Conference
• /
• 2020.06a
• /
• pp.389-389
• /
• 2020

최근 이상기후의 영향으로 게릴라성 호우 및 태풍과 같은 자연재해의 발생 요인이 증가하고 있다. 특히 여름철 집중호우는 농경지의 범람, 도심지역 저지대의 침수피해 유발, 하천 주변 저지대 및 수공구조물의 안전을 위협하고 있다. 이에 따라 본 연구에서는 HEC-RAS 5.0.3을 활용하여 금강 유역의 2차원 침수 모의를 수행하고, 그 적용성을 평가하고자 한다. 대상지역은 금강 수계 하천기본계획 보고서의 하천 횡단면도와 평면도를 활용하여 모형을 구축하였으며, 강우자료는 인근 기상관측소의 관측자료를 수집하였다. HEC-HMS를 이용하여 강우에 의한 유출량을 산정하였으며, 산정된 유출량을 HEC-RAS에 입력하여 수위를 계산하고 2차원 모의기능을 이용하여 침수해석을 수행하였다. HEC-RAS의 2차원 침수 모의 기능은 기존 1차원 하천 수위 모의와의 연계하여 하천기본계획 수립을 위한 침수 해석 등에 널리 활용될 수 있을 것이라 판단되고, 본 연구의 결과는 침수 모의 적용성 분석의 기초자료로 활용될 수 있을 것으로 기대된다.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2021.06a
• /
• pp.121-121
• /
• 2021

기후변화의 영향으로 국내의 강우량과 강우패턴의 변화가 나타나고 있다. 최근 30년 여름철 집중호우의 평균강수량은 1980년 694.5 mm에서 2000년대 768.7 mm로 평균강수량이 74.2 mm 증가하였다. 평균강수일수는 36일에서 40일로 약 4일 증가하였다. 집중호우의 증가로 국소적 홍수에 의한 재해규모가 증가하고 있는 실정이다. 토양침식은 물의 순환과정에서 있어 나타나는 하나의 현상으로 토양손실을 의미한다. 강우량과 지형 및 토양특성이 토양침식량을 결정하는 주요한 요인이다. 토양침식은 농경지 감소, 고탁수 하천유입, 하천 및 호소내 퇴적으로 인한 수생태환경 변화 등의 다양한 문제를 발생시키고 있다. 그동안 우리나라는 토양침식량을 예측하기 위해 연평균 토양침식예측모형을 적용하고 있으며, 최근에 강우강도를 고려한 토양침식모형에 관한 연구가 진행되고 있다. 본 연구는 동일한 강우량을 Huff 방법을 이용하여 24시간 강수량 자료를 만들고 물리적기반 토양침식모형에 적용하여 나타나는 토양침식과 퇴적 공간분포에 대하여 분석하고자 한다.

• Journal of the Society of Disaster Information
• /
• v.19 no.3
• /
• pp.519-531
• /
• 2023

With the aim of preventing safety accidents at construction sites, the company aims to create safe behaviors intended through variables called smart safety and health activities to help reduce industrial accidents. Purpose: It analyzes how smart safety and health activities affect accidents caused by unsafe behavior and changes in worker behavior, which is the root cause, and verifies the hypothesis that it helps prevent safety accidents and protect workers' lives. Method: Smart safety and health activities were selected as independent variables (X), and intended safety and anxiety, which are workers' behavioral intentions, were set as dependent variables (Y), attitude and subjective norms, and planned behavioral control as parameters (M). Exploratory factor analysis, discriminant validity analysis, and intensive validity analysis of safety and health activities were used to analyze the scale's reliability and validity. To verify the hypothesis of behavior change, the study was verified through Bayesian model analysis and MC simulation's probability density distribution. Result: It was found that workers who experienced smart safety and health activities at construction sites had the highest analysis of reducing unstable behavior and performing intended safety behavior. The research hypothesis that this will affect changes in worker behavior has been proven, the correlation between variables has been verified in the structural equation and path analysis of the research analysis, and it has been confirmed that smart safety and health activities can control and reduce worker instability. Conclusion: Smart safety and health activities are a very important item to prevent accidents and change workers' behavior at construction sites.

• Journal of the Korea Institute of Building Construction
• /
• v.16 no.4
• /
• pp.349-357
• /
• 2016

Recently, the quantity of risk in construction project has been inflated due to the fact that current construction projects have been large and complicated. Therefore, a study on the risk management methods is necessary that can predict and respond to the need in complicated modern construction projects. In this study, the objective is to analyze the cause of accident in actual construction sites and develop a risk assessment model based on insurance claims records. To reach the goal of this study, first, the frequency and severity of accidents are analyzed the causes of accidents based on the classification; progress rate, season, and total construction costs. Second, a risk assessment model is developed by utilizing a multiple regression analysis. The dependent variable is loss ratio of material damage and three categories; natural hazards, geographic information, and construction method & ability, are used as the independent variables. The model's adjusted R-square is 0.455. The contributions of this study will be used as a material for a quantitative risk analysis model development and review of the construction risk factors for future study.

• Korean Journal of Construction Engineering and Management
• /
• v.10 no.5
• /
• pp.37-46
• /
• 2009

This research will focus on the public agencies, designers, supervisors, building cooperation, and contractor who involved in urban development plan. By understanding the complexity and the priorities in urban development process, all problems of the urban development projects can be solved or improved. These priorities are specified using AHP (Analytic Hierarchy Process). A questionnaire survey is employed to identify the problems of urban development process and the methods of revitalizing urban in this research. Through the survey, 35 issues are drawn out. Factor analysis technique is applied to extract the underlying interrelationships possibly existing. Using latent root criterion and varimax rotation method, 9 factors are extracted(by using 34 issues after deleting 1 issue less than 0.4 of factor loading) These 9 factors named as PIF (Problem Improvement Factor) consist of integration estimation (PIF1), cooperation operation capability (PIF2), contractor corporation capability (PIF3), capital for infrastructure investment (PIF4), misunderstanding of effective land use (PIF5), financial capability (PIF6), obscure goal of project (PIF7), shortage of cooperation expertise (PIFS), administrative procedures (PIF9). PIF 6 is the most important factor and PIF 1 is the most widely effective factor to succeed urban land development projects. It is recognized that administrative office is most responsible for PIF1 cooperation is most responsible for PIF2, 7, 8 and 9; contractors is most responsible for PIF3 and PIF6; administrative agencies is most responsible for PIF4; cooperation and consultants are responsible for PIF5. From findings in this study, some suggestions are proposed for the revitalization methods of urban development projects through the land readjustment method.

• Journal of the Korea Institute of Building Construction
• /
• v.20 no.3
• /
• pp.297-304
• /
• 2020

Design for Safety(DfS) at the design stage is introduced and executed in order to fundamentally reduce the occurrence of construction safety accidents in Korea. Therefore, in this study, the construction method selected by Design for Safety can reduce safety accidents, but the effects on construction duration and costs were examined to confirm the effectiveness of various aspects. The construction method of the structural frame for the exterior wall cladding of the building, which have the factors for the fall accident, was selected for construction safety and compared and analyzed in terms of construction duration and costs. As a result, it was found to be effective not only in terms of safety, but also in terms of construction duration and costs. Therefore, it is considered that the construction method selected by the Design for Safety at the design stage will have a positive effect on the entire construction project.

• Journal of the Society of Disaster Information
• /
• v.17 no.2
• /
• pp.306-318
• /
• 2021

The dispatch law has a negative impact on safety management at construction sites as the command and command relationship to safety assistants of the original contractor are applied to the dispatch law. Purpose: The purpose is to study the importance and impact of safety management according to the dispatch law, and to propose a direction for safety management so that safety assistants can actively and proactively prevent accidents. In this study, we used AHP analysis techniques for experts to achieve the final goal and verified the suitability through logistic regression. Method: AHP analysis technique is used for experts and workers and logistic regression analysis is conducted. Result: The result of analyzing scenario data where the dispatch method can be applied showed the importance in the order of education (SkillUp education), management (work-time management) and direct instructions (feedback instruction). In logistic regression analysis, feedback is the factor that affects direct instruction, and in education management, the ratio of education management is 3.42 times lower than that of other groups when only the team leader of the company gives work instructions. Conclusion: The management of feedback and education is more important than anything else within the range in which the dispatch method is not applied, and the expansion of non-face-to-face online education is judged to avoid the violation of dispatch method because the expansion of non-face-to-face online education due to covid 19 recently has brought more various target for safety education.

• Journal of Korean Society of Disaster and Security
• /
• v.13 no.4
• /
• pp.25-36
• /
• 2020

An increasing frequency and intensity of natural disasters have been observed due to climate change. To better prepare for these, the MOIS (ministry of the interior and safety) announced a comprehensive plan for minimizing damages associated with natural disasters, including drought and heavy snowfall. The spatial-temporal pattern of snowfall is greatly influenced by temperature and geographical features. Heavy snowfalls are often observed in Gangwon-do, surrounded by mountains, whereas less snowfall is dominant in the southern part of the country due to relatively high temperatures. Thus, snow depth data often contains zeros that can lead to difficulties in the selection of probability distribution and estimation of the parameters. A generalized mixture distribution approach to a maximum snow depth series over the southern part of Korea (i.e., Changwon, Tongyeoung, Jinju weather stations) are located is proposed to better estimate a threshold (𝛿) classifying discrete and continuous distribution parts. The model parameters, including the threshold in the mixture model, are effectively estimated within a Bayesian modeling framework, and the uncertainty associated with the parameters is also provided. Comparing to the Daegwallyeong weather station, It was found that the proposed model is more effective for the regions in which less snow depth is observed.

• Journal of the Korean Institute of Gas
• /
• v.17 no.4
• /
• pp.18-25
• /
• 2013

It may occur health hazards or death by suffocation or acute poisoning in case of oxygen deficiency in ambient or exposure to harmful gas. As a part of accident prevention, we studied the change of activity and lethal dose by changing the concentration of several hazardous gas with inhalation exposure chamber and laboratory animals. We investigated the lethality and motility change during either the 4 hrs whole body exposure to oxygen, nitrogen, toluene, $H_2S$, CO and 48 recovery. As results, it is estimated that 5% oxygen concentration as lethal concentration and 5.5% as $LC_{50}$ (rat, 4 hrs) with statistics for dose-response. The results of lethality in oxygen deficient condition (approximately 6%), the lethalities were 40%, 20% with 20 ppm $H_2S$, 600 ppm CO respectively, and was not increased the lethality with 8% CO. Thus, it was confirmed that the $H_2S$, CO had influence to lethal dose, while toluene had low fluence.

• Journal of Korea Water Resources Association
• /
• v.55 no.6
• /
• pp.421-435
• /
• 2022

As natural disasters have been increasing due to climate change, sustainable solutions are in need to alleviate the degree of drought hazard, assess and project the drought influence based on future climate change scenarios. In assessing drought risk, socio-economic factors of the region must be considered along with meteorological factors. This study categorized drought hazard, exposure, and vulnerability as three major components of drought risk according to the Intergovernmental panel on Climate Change (IPCC) risk assessment framework, and selected indices for each component to quantify the drought risk in South Korea according to the mid-size basins. Combinations of climate scenarios (Representative Concentration Pathway; RCP 2.6 and RCP 8.5) and socio-economic scenarios (Shared Socio-economic Pathways; SSP 1, SSP2 and SSP3) for the near future (2030-2050) ant the far future (2080-2099) were utilized in drought risk analysis, and results were compared with the historical data (1986-2005). In general, the drought risks for all scenarios shows large increases as time proceeds to the far furture. In addition, we analyzed the rank of drought hazard, exposure, vulnerability for drought risk, and each of their contribution. The results showed that the drought hazard is the most contributing component to the increase of drought risk in future and each basin shows varying contributing components. Finally, we suggested countermeasures for each basin according to future climate change scenarios, and thus this study provides made the basis for establishing drought management measures.