• Industry Promotion Research
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• v.8 no.4
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• pp.37-46
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• 2023

Due to the aging, advancement, and complexity of chemical facilities, non-routine work such as facility inspection, repair, or maintenance work is increasing. Of the 1,483 accidents that occurred over the past 10 years at chemical product manufacturing sites subject to PSM, accidents that occurred during non-routine work accounted for 56% (932 Cases) of the total. It can be seen that more accidents occur during non-routine work than during routine work. In particular, in order to improve the economy and efficiency of factory operation, there are cases where some facilities are stopped without stopping the entire factory and then inspection, repair, or maintenance work is performed while isolated from the operating facilities. Therefore, first, a safe isolation method must be selected by establishing an isolation standard (Baseline Isolation Standard) based on the chemicals handled, operating conditions, and risk level of the equipment in the chemical plant. Second, since current domestic laws and standards do not suggest the need for specific quarantine standards, it is necessary to institutionalize the preparation of quarantine standards. Technical and institutional improvements are needed to prevent fires, explosions, and poisoning accidents caused by leaks of chemical substances.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.1005-1008
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• 2007

모바일 네트워크 환경은 언제 어디서나 네트워크를 사용하는 모바일 서비스를 편리하게 사용할 수 있도록 해준다. 그러나 언제 어디서나 서비스를 제공받을 수 있다는 것은 언제 어디서든지 정보가 누출되거나 왜곡될 위험성 또한 존재하기 마련이다. 특히, 프라이버시 문제가 해결되지 않고서는 우리 일상생활과 융합되어 편리함을 제공해주는 모바일 네트워크 환경이 오히려 모바일 네트워크 감시 체제를 구축하는 심각한 역기능을 초래하게 될 것이다. 모바일 단말기들은 크기와 모양이 다양하고 컴퓨팅 연산 능력이 적은 저성능 휴대 장치들이 많기 때문에, 컴퓨팅 연산이 많이 요구되는 공개키 암호 기술을 저성능 모바일 단말기에 적용하기는 힘든 상황이다. 이에 본 논문에서는 프라이버시 문제를 해결하면서, 컴퓨팅 연산 능력이 적은 저성능 모바일 단말기에 적용할 수 있는 자바 기반의 암호 모듈 및 PKI 기반의 사용자 인증을 제안하고자 한다. 국내 표준 암호 알고리즘(SEED)과 인증서를 기반으로 세션키와 공개키를 조합함으로서 최소한의 암복호화 연산을 통해 인증 및 전자 서명을 제공하며, 이를 대표적인 모바일 단말기인 PDA 환경에서 세션키 분배 및 사용자 인증이 안전하게 이루어짐을 확인할 수 있었다.

• Journal of the Korean Institute of Gas
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• v.10 no.1 s.30
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• pp.48-55
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• 2006

In order to establish the comprehensively, quantitatively predictable program to the fire and explosion accidents in the urban gas system, and to set up domestic criteria of societal risk, the collected urban gas accident data have been deeply analyzed. The Poisson probability distribution functions with t=5 for the database of the gas accidents in recent 11 year shows that 'careless work-explosion-pipeline' item has the lowest frequency, whereas 'joint loosening & erosion-release-pipeline' item has the highest frequency. And thus the proper counteractions must be carried out. The further works requires setting up successive database on the fire and explosion accidents systematically to obtain reliable analyses.

• Nuclear Engineering and Technology
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• v.27 no.6
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• pp.870-876
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• 1995

In this paper, a new three-dimensional nodal diffusion code which is based on the AFEN methodology is described and tested. The method expands the homogeneous flux within a node in ter-ms of eighteen analytic basis functions satisfying the diffusion equation at any point of the node. And the nodal coupling equations are derived such that nodal balance, current continuity and leakage balance within an infinitesimally small box around the edge are satisfied. To verify its accuracy, the code was applied to the well-known static LMW benchmark problem and a small core benchmark problem that has the same material properties as the three-dimensional IAEA benchmark problem and compared with two other codes (QUANDRY, VENTURE). The results show that the code provides good accuracy both in the power distribution and in the effective multiplication factor.

• Journal of Korean Society of societal Security
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• v.1 no.1
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• pp.53-62
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• 2008

Recently, the potential risks of tank lorry transportation from the petrochemical plant have been increasing, so the research was performed to build up the evaluation criterion of the transportation safety, as well as aggressive risk+assessment of a variety of chemical materials. This research was applied to the Maximum Credible Accident Analysis technique and modeled on the risk management of chemical transportation using the following four steps for risk evaluation, firstly the comparison of representative fype and standard of hand ling chemical materials transported by tank vehicles secondly, specific classification of potential hazards thirdly, grasp and recognition of virtual accident scenario at last, the risk evaluation of virtual accident scenario(qualitative/quantitative - chemical release modeling).

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.2
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• pp.77-86
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• 2010

This paper presents an efficient secure scan design technique which is based on a fake key and IEEE 1149.1 instruction to protect secret key from scan-based side channel attack for an Advanced Encryption Standard (AES) core embedded on an System-on-a-Chip (SoC). Our proposed secure scan design technique can be applied to crypto IP core which is optimized for applications without the IP core modification. The IEEE 1149.1 standard is kept, and low area, low power consumption, very robust secret-key protection and high fault coverage can be achieved compared to the existing methods.

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.162-163
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• 2017

해양 HNS(Hazardous and Noxious Substances)의 유출 사고 시, 막대한 인명 피해와 환경 훼손을 피하기 위해 유출 사고 조기 예측과 정확한 확산 경로를 예측하는 것이 필수적이다. 본 연구의 최종목적은 전산유체역학을 이용하여 HNS사고가 발생하였을 때 위험구역을 적절히 예측할 수 있는 수치해석기법을 개발하고, 다양한 해양사고조건과 환경영향을 고려하여 근접역에서의 2차원 확산 특성을 고찰하고 확산 현상을 예측하기 위한 모델을 개발하는 것이다. 본 연구에서는 상용코드인 ANSYS FLUENT(V. 17.2)을 사용하여 근접역에서의 2차원 확산특성을 모사하고 분석하였다. 특히, 누출된 HNS의 위치별 농도를 예측하기 위해 종수송방정식(Species Transport Equation)을 이용하였으며 RANS(Reynolds-Averaged Navier-Stokes) 방정식과 표준 $k-{\varepsilon}$ 모델을 이용하여 난류유동을 모사하였다. 해석된 결과는 문헌에서 얻어진 실험데이터와 상호비교하였으며 해수의 유속, HNS의 밀도에 따른 유층 두께, 해수면 HNS 평균 농도 그리고 HNS 전파 속도를 분석하였다. 유층 두께는 해류 유속에 따라 변화하며 변화 경향에 따라 두 구간으로 나눌 수 있다. 해류 전파 속도는 대체로 해류 유속과 선형적 비례관계를 갖는 것으로 나타났다. 해수면 평균 HNS 농도는 해류 유속에 선형적으로 비례하여 감소하며, HNS 밀도가 큰 경우 해수면 평균 HNS 체적 농도는 더 빠르게 감소하게 된다. 이러한 결과는 HNS 확산 특성을 분석하고 관련된 예측모델을 개발하는 데에 기여할 수 있다.

• Journal of the Korean GEO-environmental Society
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• v.18 no.10
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• pp.23-34
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• 2017

As the electrical property of fully saturated soils is dependent on the pore water, it has been commonly used for the detection of the contamination into the ground. The objective of this study is to investigate the electrical characteristics according to the salinity and the lead concentration in fully saturated soils. Fresh water and saline water with the salinity of 1%, 2% and 3%, which are mixed with 6 different lead solutions with the range of 0~10 mg/L, are prepared in the cylindrical cell incorporated with sensors for measuring electrical resistance and time domain reflectometry signal. Then, the dried sands are water-pluviated into the cell. The electrical resistance and the time domain reflectometry signal are used to estimate the electrical conductivity. Test results show that electrical conductivity determined from electrical resistance at the frequency of 1 kHz continuously increases with an increase in the lead concentration, thus it may be used for the estimation of the contaminant level. In addition, the electrical conductivity estimated by the time domain reflectometry changes even at very low concentration of lead, the variation rate decreases as the lead concentration increases. Thus, the time domain reflectometry can be used for the investigation of the heavy metal leakage. This study demonstrates that complementary characteristics of electrical resistance and time domain reflectometry may be used for the detection of the leakage and contamination of heavy metal in coastal and marine environments.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.308-316
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• 2020

This study attempted to derive an equation for calculating the damage impact distance using CARIS so that local governments can quickly determine evacuation and notification of residents in the event of an ammonia-release accident. Ammonia is an accident-causing substance and one of 16 substances to prepare for resident evacuation. It is the most frequently occurring chemical with 58 chemical accidents from 2014~2019. The study derives an equation for calculating the damage impact distance according to the exposure time of ammonia based on AEGL, an acute exposure standard applicable to the general population, which is includes vulnerable groups such as infants, children and the elderly and designated by the EPA. The calculation formulas for each concentration and exposure time to classify the hazardous area according to AEGL-3 and the semi-dangerous area according to AEGL-2 were derived. A comparison of the relative standard deviation between the damage impact distance values of CARIS revealed that is was in the range of 0~2%. Local governments should consider the actual accident situation and apply the appropriate damage-affected distance calculation formula derived from the study to evacuate residents near the origin of the accident or use for protective measures such as indoor evacuation notification.

• Fire Science and Engineering
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• v.30 no.5
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• pp.1-8
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• 2016

Safety management in hazardous areas with potentially explosive gas atmospheres (here in after referred to as hazardous areas) in large scale facilities dealing with combustible or flammable materials at home and abroad is very important (significant) for the coexistence of the company and local society based on business continuity management (BCM) and reliance. For the safety management in hazardous areas, two systems are mainly used: (1) the control system for the prevention of combustible or flammable substances and (2) the explosion proof system for the elimination of ignition sources when flammable gases are leaked to inhibit the transition to fire or explosion accidents. While technology and regulations on explosion proof facilities or devices for electrical ignition sources are well developed and defined, those for thermal ignition sources need to be more developed and established. In this study, the internal combustion engine in hazardous areas was investigated to determine the risk of ignition. For this purpose, document searches were conducted on the relevant international standards and accidents cases and risk analysis reports. In addition, this study assessed the application cases of the diesel engine's safety equipment, such as spark arresters regarding the site of process safety management (PSM) system in central Korea. To practically apply these results to the hydrocarbon industry, the safety management method for explosion prevention in hazardous areas was provided by risk identification for ignition sources of internal combustion engines, such as diesel engines.