• Journal of Environmental Impact Assessment
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• v.26 no.4
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• pp.242-256
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• 2017

In this paper, dispersion scenarios concerning various meteorological conditions and real urban structures were made to estimate the impacts of hazardous substance leakage accidents and to reduce damages. Based on the scenario of the hazardous substance dispersion, the characteristics of the risk in the pedestrian environment were analyzed in Gangnam, Seoul. The scenarios are composed of 48 cases according to the meteorological conditions of wind direction and wind speed. In order to analyze the dispersion characteristics of the hazardous substances, simulations were conducted using a computational fluid dynamic (CFD) model with hydrogen fluoride releases. The validation for the simulated wind was conducted at a specific period, and all the calculated verification indices were within the valid range. As a result of simulated dispersion field at pedestrian level, it was found that the dispersion pattern was influenced by the flow, which was affected by the artificial obstacles. Also, in the case of the weakest wind speed of the inflow, the dispersion of the hazardous substance appeared in the direction of the windward side at the pedestrian level due to the reverse flow occurred at lower layers. Through this study, it can be seen that the artificial structures forming the city have a major impact on the flow formed in urban areas. The proposed approach can be used to simulate the dispersion of the hazardous substances and to assess the risk to pedestrians in the industrial complexes dealing with actual hazardous substances in the future.

• Journal of the Korean Society for Marine Environment & Energy
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• v.1 no.1
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• pp.56-65
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• 1998

An oil spill model, Green Sea Ranger(GSR) based on trajectory and fate modeling of spilt oil behavior is introduced. The various physical models on weathering processes are reviewed and those adopted by GSR are described. A database for currents, which is necessary for the real-time simulation of oil spill, is generated on the south sea of Korea. The real-time prediction of tidal currents in the South Sea of Korea is carried out. Four major constituents (M₂, S₂, K₁, O₁ tide) are employed in the prediction, and those angular speeds and phases are determined from the astronomical arguments. The harmonic constants of the constituents are computed by solving shallow-water tide equations. The GSR has user-freiendly GUI and flexible framework which makes it easy to expand the database for sea environments in Korean coastal waters. The GSR is validated by the simulation of O-Sung oil spill caused by a grounded oil tanker in coastal sea near Maemol-do. The simulated trajectory is compared with observed one and it is shown that the GSR gives reasonable estimation on spilt oil bahavior.

• Korean Chemical Engineering Research
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• v.55 no.1
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• pp.48-53
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• 2017

Since the number and the amount of toxic substances handled by domestic companies have been increased, the possibility of serious chemical accidents has become severe. According to Chemistry Safety Clearing-house (CSC), the number of chemical accidents for the last five years has been rapidly raised. A representative example which shows the serious impact of a chemical accident is HF (Hydrogen Fluoride) accident generated in Gumi in 2012. In order to make effective responses for mitigating losses of accidents, the most suitable consequence model has to be selected and implemented throughout the considerations of chemical properties and environments. Even if each consequence model has been verified by the results of experiments, it is necessary to analyze and compare the usability of them according to various scenarios. In this study, the Gumi HF accident is simulated by HGSYSTEM, which is the most specialized model for the release and dispersion of HF. It is found that the ending point of ERPG-2 is about 1 km from the accident point. In order to investigate the usability of the most representative consequence models (ALOHA and CARIS), the results of them are compared with one of HGSYSTEM.

• Proceedings of The KACE
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• 2018.01a
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• pp.63-67
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• 2018

미래형 인재의 필요성과 시대의 변화 및 요구를 반영하여 전 세계적으로 메이커 운동이 일어나고 메이커 활동의 교육적 가치를 인정받아 새로운 교육방법이자 패러다임으로서 우리나라의 메이커 교육도 점차 확산되고 있다. 하지만 학교 교육과정에서 활용할 메이커 교육 콘텐츠는 부족한 실정이며 2015 개정교육과정에 따라 소프트웨어 교육을 뒷받침하고, 초등학교에서 학교 교육과정의 변화를 받아들이면서 창의융합형 인재를 양성할 수 있는 소프트웨어 교육이 이루어질 수 있도록 디자인 사고 기반 메이커 교육프로그램을 개발하고자 한다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1999.04a
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• pp.4-4
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• 1999

최근 충남대에서는 다양한 추진제와 연소 조건으로 액체로켓 연소 실험이 진행되고 있으며 그에 비례하여 많은 사고들이 발생하고 있다. 한 예로 GO$_2$/kerosene을 추진제로 하는 노즐삭마 시험용 로켓엔진(추력 1001bf, 연소실 압력 600psia) 개발 중에 화염이 인젝터면에 형성되어 인젝터면을 손상시키는 사고를 여러 번 경험하게 되었다. 본 연구는 인젝터 손상의 원인을 규명하여 안정적인 인젝터 설계에 도움을 주기 위한 목적으로 실험용 동축 인젝터를 제작하여 화염 부상 특성을 실험적으로 연구하였다. 사용된 인젝터는 연료인 Kerosene을 접선형 선회기로부터 90$^{\circ}$의 원뿔 각을 가지고 분무되도록 설계하였으며, 그 주위로 산하제인 GO$_2$가 연소실의 축방향에 수평하게 분무되도록 설계하였다. 2-유체 동축 인젝터의 난류 확산 화염에서 연료와 산화제의 혼합은 화염 특성을 결정하는 주요 변수이므로 인젝터로부터 분무되는 추진제간의 유량을 변화시켜 화염 부상 특성을 연구하였다.

• The Journal of the Korea Contents Association
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• v.15 no.9
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• pp.662-669
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• 2015

The purpose of this study is to explore plan for increasing the analysis and understanding skills of literary works by using systemic thinking technique. This study used a literatures analysis method. The concrete study contents are as follows; First, it is centered on presenting values of literary education through analysing fairy tales conditions in Korean textbooks in relation to national curriculum for elementary and middle school. Second, it is to explore the features of systemic thinking technique. Third, it is to draw the instruction design model and application. Main expected effects of this study are breakaway from habitual routine, developing comprehensive and logical thinking ability, expanding fancy and imagination, cultivating innovative problem solving skill, inducing interest in literature, and increasing linguistic skills. That is, it is to be effective instruction strategy to enhance creativity and to cultivate character in classroom.

• Korean Journal of Cognitive Science
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• v.26 no.4
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• pp.393-433
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• 2015

Creativity refers to the ability to generate novel and useful ideas. Understanding the mechanism of creativity and its enhancement is important in order to solve major problems of the modern society and to improve the wellness of mankind. Creativity is a highly heterogeneous and complex ability which should not be conceptualized as a single entity. Thus, the current literature on creativity is based on a component process approach to creativity. The present study introduces cognitive neuroscience research studying the mechanism of divergent thinking, insight, relational thinking and artistic creativity which are the major components of creativity. Based on an expansive review, the early hypothesis of hemispheric asymmetry emphasizing the importance of the right as opposed to the left hemisphere is not supported by scientific evidence. In addition, there is no consensus or consistency on which specific brain region is related to a certain component of creativity. In fact, there is a mixture of studies reporting involvement of various brain regions across all four lobes of the brain. This inconsistency in the literature most likely reflects heterogeneity of the component processes of creativity and sensitivity of the neural response to differences across tasks and cognitive strategy. The present study introduces examples of representative studies reporting seminal findings on the neural basis and the enhancement of creativity based on innovative methodology. In addition, we discuss limitations of the current cognitive neuroscience approach to creativity and present directions for future research.

• Korean Chemical Engineering Research
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• v.54 no.4
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• pp.582-585
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• 2016

This study intends to provide initial evacuation distances for the public in case of accidental releases of hydrogen fluoride (HF). HF is a very toxic chemical that is widely used in the chemical, electrical, and electronics industries. Consequence modeling programs, such as ALOHA and PHAST, were used to help formulate a contingency plan in case of an HF leak. For the purpose of this study, the release of entire quantity of HF in 10 min is defined as a worst-case scenario and the release from a partial line rupture is used as an alternative case scenario as National Institute of Chemical Safety (NICS) guidelines. Once the discharge rates were calculated based on the scenarios, the ERPG-2 endpoint distances have been obtained for representative daytime and nighttime weather conditions. This paper presents graphs that can be used to enact swift evacuation orders and emergency response plans in the case of accidental releases of HF.

• Journal of Convergence for Information Technology
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• v.11 no.3
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• pp.147-158
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• 2021

The purpose of this study is to perform of composition of young children teacher's verbal interactions and problem solving strategies by semantic network analysis. The data was collected the narrative of teacher in young children's environmental education. Additionally, this study used categories as a unit of analysis in order to find out structural characteristics. The results of this study were as follows. First, teacher's verbal interactions, providing information was the most cental, high influence appeared along with integration. Second, teacher's problem solving strategies, suggestion was the most cental, high influence appeared along with divergent thinking. Third, teacher's verbal interactions and problem solving strategies, suggestion was the most cental, providing information and divergent thinking appeared a strong connection. Besides, suggestion and decision were mediated by concern of problem, assessment appeared connection. Through these results from this study it is suggested that in order to interact and support problem solving process in young children's environmental education, teacher education to respond and understand contextually with young children is necessary.

• Fire Science and Engineering
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• v.16 no.4
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• pp.49-58
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• 2002

A large number of accidents at an underground place have been happening, including the gas explosion under construction of subway; the fires of underground utility and underground shopping malls, and other explosion, at home and abroad recently. These accidents make the function of a city ineffective due to the paralyses of electricity and communications net as well as the loss of property and cause people to feel unsecured with accompaniment of a heavy of toll of lives. This research will show evaluation methods of a numerical value of expected average loss space of combustion with the use of probability in order to present potential risk of combustion growth that underground space might cause, and how designer decides a system that enables us to compare and evaluate relatively the effectiveness of measures for preventing burning by calculating the expansion route and the damage size of burning in case of fire.