• Composites Research
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• v.18 no.1
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• pp.55-66
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• 2005

Beside fire resistance, for Phenolic Composites(here-in-after PCs), in actual, moisture resistance are also needed when they are applied to components in wet uses such as in Naval vessels and in off-shore operations where direct water contact may be expected. PCs have so-called 'Micro-porous' when they are made by normal GRP manufacturing techniques, which causes much larger amounts of water absorption in them to higher level of around $7\%$. So, this figure, which indicate impending disaster in a polyester matrix laminate, has made some specifiers suspicious of the effect of the water on mechanical performance of PC in 'wet' service. To solve this problem, a large amount work has been carried out by workers in UK and US. This paper is an attempt to explain that the effect of the high water absorption of PCs is not the disaster that some 'prophets' may foretell. Let's open our next door fur better society much safetyfied by our own efforts with PCs. like in UK.

• Journal of the Korean Institute of Gas
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• v.24 no.5
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• pp.74-81
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• 2020

In general, when manufacturing a semiconductor, a number of hazardous and dangerous substances such as flammability, toxic, and corrosiveness are used. In particular, semiconductors are manufactured using specialty gas in processes such as CVD and etching. The specialty gas is filled in a container in the state of compressed or liquefied gas, and a gas cylinder cabinet is used as a facility for supplying this specialty gas to the semiconductor manufacturing process. When a accident occurs in the gas supply system, gas is released through a pressure release device installed in the gas cylinder to secure the safety of the supply system. In this case, the gas released inside the gas cabinet, there is a risk of leaking to the outside. After that, by analyzing the gas flow in the gas cabinet, it is intended to identify the risk associated with leak and to provide measures to prevent accidents.

• Journal of the Korean Society for Nondestructive Testing
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• v.29 no.2
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• pp.162-170
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• 2009

As one of promising solutions to overcome high oil price and energy crisis, the construction market of high value-added LNG plants is spotlighted world widely. The purpose of this manuscript is to introduce domestic activities to develop risk assessment technology against overseas monopolization. After analyzing relevant specific features and their technical levels, risk assessment program, non-destructive reliability evaluation strategy and safety criteria unification class are derived as core technologies. These IT-based convergence technologies can be used for enhancement of LNG plant efficiency, in which the modular parts are related to a system with artificial optimized algorithms as well as diverse databases of facility inspection and diagnosis fields.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.189-189
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• 2011

최근 공동주택은 보편적인 도시주거 유형으로 자리매김 하고 있지만, 성장 위주의 경제 산업 정책에 따른 안전의식미약, 사회구조개편에 따른 급격한 증가, 생활환경 변화와 에너지 사용 증가 등 화재 유발인자의 다양화로 인해 인적 물적 피해가 증가하고 있는 실정이다. 특히 다른 건물들과는 달리 공동주택의 거주자가 유아, 노인, 신체장애자 등 다양한 인적 구성의 형태로 이루어져 있어서 화재 발생 건수에 비해 인명피해가 월등히 높은 편이다. 공동주택에서의 화재에 대한 위험성을 인식하고, 그에 대한 인적 물적 피해를 최소화하기 위한 대책 마련이 시급하다. 본 논문은 CFAST(Consolidated Model of Fire Growth and Smoke Transport)를 사용하여 공동주택을 대상으로 실물 화재 실험을 실시하고 공간화재에서의 화재 성상을 파악하여 화재 시 개구부의 개폐 여부에 따라 발생되는 산소와 이산화탄소의 농도와 온도가 인체에 미치는 영향에 대해 알아본다. 개구부를 개방 했을 경우에 외부창문의 개폐 여부에 상관없이 모든 방의 온도 분포가 뚜렷하게 나타났지만 개구부를 폐쇄 할 경우에는 발화지점인 거실의 온도 분포만 나타났다. Flashover현상과 Back Draft현상은 개구부의 개폐여부에 상관없이 외부 창문을 폐쇄 했을 경우에 나타났지만 특히 모든 개구부와 외부창문을 폐쇄 했을 경우에 더욱 뚜렷하게 나타났다. 각 실은 점화 후 4분경에 최고 온도를 보였으며 다른 방에 비해 발화지점인 거실의 온도가 가장 높게 나타났다. 온도에 의해서는 두 가지 영향이 일어날 수 있는데, 하나는 비교적 장시간에 걸쳐 발생하는 열응력이고, 다른 하나는 짧은 시간에 발생할 수 있는 화상이다. 만약 피부온도가 $45^{\circ}C$에 이르면 인체는 고통을 느끼게 되며, 이보다 더 높은 온도에서는 깊은 피부조직까지 손상을 줄 수 있다. 움직이지 않는 사람에 대한 고통 유발 임계온도는 약 $200^{\circ}C$이며, 인체는 땀의 발산으로 온도에 대한 내성이 증가하지만 이체가 장시간 열을 받으면 사망에 이를 수 있다. 결론적으로 공동 주택을 대상으로 CFAST를 이용해 분석한 결과 플래쉬오버 현상으로 인해 화재가 성장하여 급격히 온도가 상승하다가, 산소 부족으로 인해 화재가 성장하지 않고 온도가 떨어지는 것을 알 수 있다. 화재 시 온도, 산소, 이산화탄소를 고려하였을 때 약 3분 이내에 대피해야 온도 및 가스로 인한 피해를 줄일 수 있을 것으로 판단된다.

• Journal of the Korean Institute of Gas
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• v.16 no.4
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• pp.32-37
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• 2012

The aim of this study is to evaluate the characteristics of explosion and flame velocity that can be utilized to factories where Mg-Al alloy metal powders are handled in the form of raw materials, products or by-product for similar dust explosion prevention and mitigation. Because the strength of the blast pressure is the result due to flame propagation, flame velocity in dust explosion can be utilized as a valuable information for damage prediction. An experimental investigation was carried out on the influences of content ratio of Mg-Al alloy (mean particle size distribution of 151 to 161 ${\mu}m$). And a model of flame propagation velocity based on the time to peak pressure and flame arrival time in dust explosion pressure, assuming the constant burning velocity, leads to a representation of flame velocity during dust explosion. As the results, the maximum flame velocity of Mg-Al(60:40 wt%), Mg-Al(50:50 wt%) and Mg-Al(40:60 wt%) was estimated 15.5, 18 and 15.2 m/s respectively, and also tend to change with content ratio of Mg-Al.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.23 no.3
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• pp.239-249
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• 2005

It is the general consensus that korea is safe from some disasters, particularly earthquake. However, it is not difficult to see the countries considered as safety zones have occasionally experienced a severe earthquakes. In this case, damages and casualties are much serious because they were not prepared for the earthquakes. Therefore, it is necessary to establish a counterplan about an earthquake. In this paper, we analyzed several damages by earthquakes using GIS based methods, and derived a counterproposal. The disasters caused by earthquakes are categorized into three riskiness factors, that is, a building destruction riskiness, a blaze riskiness and a refuge riskiness. Then, it is quantitatively analyzed by the degree of damage so that overall riskiness of the earthquake are assigned. In addition, it was shown that the analysis can be utilized to establish the escape route from the earthquake. It is expected that this study shows an good example of GIS application especially for preventing disasters.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.15 no.1
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• pp.21-28
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• 1997

Since beginning of subway construction in 1974, for supplying the demand for increasing urban traffic and solving the traffic jam due to expansion of society and elevation of an individual income, the $1^{st}\;and\;2^{nd}$ construction have been almost done and $3^{rd}$ has been driving forward. However, according to an increment of com-mon usage with the passage of time, structures are superannuated and the amount of improvement and repairs keeps on increasing continuous. And many problems are taking place at underground space because of new constructions for underground facilities such as urban gas, electric power, waterworks, and sewerage. In consequence. The consideration of a counterplan for safety is required deeply This study analyzed problems on maintenance of structure about $1^{st}$ class subway, and will present means that a manage civil structures scientifically and systematically by using GSIS concept that imported into several organizations for facility management recently as making digital graphic elements and historic data into a database rather than using an old method - documents and paper drawings.

• Journal of Korean Tunnelling and Underground Space Association
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• v.4 no.3
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• pp.247-260
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• 2002

This paper presents the design case of the 3-arch tunnel under Daejeon railroad station building. The original construction method was the underpinning method supported by pipe-roof, but it was changed to the mined tunnelling method because of the complex construction condition and the safety problem. This 3-arch tunnel has a width of 28 meters and a height of 10 meters. Overburden is only 23m and the ground around the tunnel is a weathered rock. The allowable settlements for the station building and some railroads are very strict. Accordingly, various measurements for the tunnel stability and the settlement minimization was applied and they were reviewed by 2-D and 3-D numerical analysis.

• The Journal of the Korea Contents Association
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• v.18 no.4
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• pp.1-9
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• 2018

The worldwide population is aging rapidly. In this circumstance, Korean society is in need of the urgent comprehensive countermeasures that will help the elderly with their health problems and infection control in their daily life. Universal design has supportive, adaptable, accessible and safety-oriental design standards for the elderly. Is this study, we propose the guidelines of the mobile application development based on the application of the universal design for infection control in the elderly. From the perspective of the universal design, there are several important guidelines including 'generalized access', 'simple and intuitive usage', 'low physical effort', and 'visualized language' based on the KCDC(Korea centers for disease control and prevention) principles for the elderly. These findings show that the guidelines for improving the health literacy of the mobile application via universal design are necessary to enhance the health behavior of infection control for the elderly.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.2
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• pp.195-206
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• 2020

Although the national radiological emergency response system has been improved by incorporating lessons from the Fukushima nuclear power plant accident and recent domestic natural disasters, it has not fully incorporated these lessons. In addition, it cannot deal with a variety of aftermath of the radiological disaster. Even for the same disaster, the national emergency response system should comply with multiple domestic laws in our country. Furthermore, there are a few discrepancies between the articles of the domestic laws that the national radiological emergency response system should address. Therefore, this study investigates the characteristics of radiological disasters, examines articles on the domestic laws related to the national radiological emergency response system, and analyses the Japanese government's responses to the Fukushima nuclear power plant accident. Based on the results of the review, suggestions for the improvement of the national radiological emergency response system in terms of response organization and framework have been proposed in this study.