• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.10a
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• pp.207-210
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• 2010

원자력발전소 화재방호 규정이 제정되기 이전에 설계되어 방화벽 관통부 내화성능 인증자료가 미흡하였던 국내 일부 가동원전들은 최근 성능인증이 완료되었거나 진행 중이다. 성능인증이 완료된 방화벽 관통부는 발전소 운영기간 동안 요구성능이 유지되도록 적합한 관리방안이 필요하다. 본 논문에서는 성능인증이 완료된 가동원전을 대상으로 방화벽 관통부 관리현황의 적합성을 평가하고 관리방법 및 절차를 향상시키기 위한 향후 과제를 제안하였다.

• Fire Science and Engineering
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• v.20 no.4 s.64
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• pp.98-104
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• 2006

The Fire Protection Regulatory documents require the fire-resistive rating of fire barrier penetration seals be same as that of fire barriers. Pilot application of penetration seal evaluation for K nuclear plant, built before penetration seal requirements were made, was done. In this evaluation, visual inspection and estimating fire rating by comparing installed configuration with tested configuration of penetration seals, called bounding approach method, were applied. Further improvements for retrofit and maintenance are recommended with penetration seal evaluation results also. The practical use of the methodology adopted in this study and the evaluation result of K nuclear plant will be anticipated for other plant's penetration seal evaluation.

• Journal of the Korean Institute of Gas
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• v.20 no.6
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• pp.80-88
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• 2016

A fire station and scuba have operated filling facilities for respiratory high-pressure cylinder without getting authority or reporting according to High-Pressure Gas Safety Control Act. They need facility improvement and special management to make provision for the time of accident during filling process. The Government have strived to correct illegal operations and suggested an alternative, establishing and operating the safety cabinet. It insures a safety being distance from danger caused by overpressure and a safety provoked by the protective wall equals or superiors. The safety cabinet is required to have an internal structure that smoothly distribute overpressure at the time of rupture. Plus, it needs to minimize fragments. It is also equipped with the performance of protective wall that makes overpressure to outside vent on the place where there is no person (top or bottom). This study calculated the consequence of physical explosion damage and built a prototype of safety cabinet. In addition, through the gas burst test, it derives for the ways to mitigate the physical explosion damage.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.6
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• pp.17-25
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• 2010

This paper studied on stability of the U-channel segmental concrete bridge under vehicle-impact loads. The U-channel bridge has advantages in that it reduces an additional dead load and the edge beams role as a barrier. But it has a dangerous factor which collapses the bridge structure when the edge beams are ruptured. Therefore, it is necessary to verify behaviors of the bridge system under vehicle-impact loads. Static and dynamic vehicle impact simulations were carried out on the basis of AASHTO LRFD design specifications. In case of the static analysis, equivalent static loads specified in the AASHTO codes are loaded on the edge beams and in case of the dynamic analysis, FEM vehicle models are modeled by applying the dynamic test specifications of AASHTO codes. As a result, it is shown that U-channel bridge system has sufficient safety against static and dynamic impact loads specified in the AASHTO LRFD design specifications.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3A
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• pp.323-330
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• 2008

The ship collision analysis of steel pile group as protection system of bridge in navigable waterways was performed to analyze the structural characteristics of protective structure during ship collision. The analysis encompassed finite element modeling of ship and pile, modeling of material non-linearity, hard impact analysis, displacement-based analysis and soft impact analysis for collision scenarios. Through the analysis of hard impact with a rigid wall, impact load for each collision type of ship bow was estimated. In the displacement-based analysis the estimate of energy which protection system can absorb within its maximum horizontal clearance so as to secure bridge pier from vessel contact during collision was performed. Soft impact analysis for various collision scenarios was conducted and the collision behaviors of vessel and pile-supported protection system were reviewed for the design of protection system. The understanding of the energy dissipation mechanism of pile supported structure and colliding vessel would give us the optimized design of protective structure.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.204-209
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• 1998

핵연료 펠렛이 장입되어 있는 원전연료봉 피복관은 핵분열성 물질의 외부 유출에 대한 일차 방호벽 역할을 하므로 원전의 안전성을 위해서는 피복관의 구조건전성 확보가 매우 중요하다. 고온, 고압의 운전 조건 속에서 연료봉 피복관은 산화막이 생성 상장하여 연료봉을 취성 파괴시킬 가능성이 있으므로 이를 가동중에 비파괴적으로 측정할 수 있는 방법을 개발할 필요가 있다. 산화막이 존재하는 지르칼로이 피복관에 대한 음파의 공명산란을 이론적으로 모델링하고 수치해석을 수행하였다. 산화막이 피복된 원통형 쉘의 공명산란에서 공명 원주파의 전파 특성은 산화막의 존재 여부와 그 두께 증가에 따라 크게 변화한다. 수치 해석 결과 제 1차 반대칭 (A$_1$) 원주파의 특정 부분파의 경우에는 산화막의 존재에도 불구하고 위상속도가 일정한 특이성을 보였다. 이러한 위상속도 특성을 실험을 통하여 확인하였으며 이 현상을 이용하여 산화막의 두께를 측정할 수 있는 새로운 비파괴 평가 방법을 제안하였다.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.613-618
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• 2007

The real vehicle crash experiment is the best way to evaluate the performance of a guardrail. However the experiment is very expensive because of high cost of vehicles and guardrail installation. Thus in this study, crash simulation of a vehicle against a steel guardrail is performed using LS-DYNA. There are many researches on the impact of a vehicle against a guardrail. However the friction between a vehicle and a guardrail is not considered, although it affects considerably the behavior of a guardrail. In this paper, the friction coefficient is applied to evaluate correctly the performance of a guardrail.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.05c
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• pp.2217-2220
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• 2003

정보의 편리성 및 효용성에 따라 점차적으로 생활의 일부가 되었으며, 이에 따라 타인의 정보에 접근하여 악용하는 피해사례가 늘고 있다 따라서, 인증되지 않은 외부 침입자로부터 시스템의 정보보호를 위한 많은 노력과 연구가 병행되어왔다. 즉, 침입탐지 시스템 및 암호화, 복호화 알고리즘을 적용하여 소프트웨어 측면에서의 보안기법과 방호벽 통의 하트웨어적인 보안기술이 도입 및 실용화 되고있는 것이다. 그러나, 이를 적용하기 위해서는 많은 전문전인 지식과 기술이 필요하여 일반적으로 쉽게 적용하기 어렵다. 따라서, 본 논문은 간단히 사용자의 정보를 변형함으로서 사용자정보를 갖는 데이터베이스가 노출되어도 이를 보호할 수 있도록 하였다. 즉, 정보 보호 방안으로 내부적 안전을 위한 프로그램적 기법으로 데이터를 저장할 때 중요한 자료들 데이터베이스 혹은 Mapping Array에 보관된 임의의 암호화 코트를 이용하여 암호화하여 서장하고 필요할 때 복호화 하는 시스템 내부적인 보안 방법을 제시하고자 한다.

• International Journal of Highway Engineering
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• v.10 no.4
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• pp.235-245
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• 2008

Since rapidly increase of tunnel with increasing of expressway, the study on safety improvement of safety device at entrance of expressway tunnels is necessary. The existence of tunnel occurs more speed reduction than an upward slope by itself, the collision accident of tunnel entrance causes heavier damage than that of general accident on the road. So, many kinds of safety devices such as poly-ethylene barrier, guard-rail are placed on the road side. But these devices affect the drivers as an obstacle. Although there are various safety devices that are placed at tunnel entrance, this study is related to following 2-cases. One is that the poly-ethylene barrier is placed and the other is that a safety devices is not placed. The reason that these two cases are selected, is that poly-ethylene barrier is usually placed at many tunnel entrances and safety devices can affect the drivers as an obstacle. This study is related to the difference of right-hand side clearance between inside tunnel and outside tunnel, too. The average difference observed car speed and VDS(vehicle detect system) speed nearby the tunnel is analysed. Through the statistical analysis of the average difference, this study suggests an alternatives on safety improvement of safety devices at entrance of expressway tunnels. It is concluded that the small difference of right-hand side clearance is desirable to drivers when a poly-ethylene barrier is placed. And when the difference of right-hand side clearance is large, no safety devices is desirable, and when the difference of right-hand side clearance is small, poly-ethylene barrier should be placed to improve safety.

• Journal of the Society of Disaster Information
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• v.16 no.3
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• pp.421-429
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• 2020

Purpose: The purpose of this study is to present step-by-step countermeasures to prevent fires in sandwich panel warehouses and to enhance on-site fire response capabilities. Method: Interviews of firefighters related to fire sites, advice from fire experts, and experiments on protection performance were conducted to draw up measures for each element to strengthen on-site response capabilities. Result: The fire safety management checklist for warehouse fire safety managers and the installation standards for wall protection of sandwich panel warehouses are presented. In addition, Standard Operational Procedures(SOP) for fire application of sandwich panel warehouses were established for firefighters on-site. Conclusion: Through this study, step-by-step fire safety measures were established for preventing, protecting and suppressing fires in sandwich panel warehouses.