• Journal of the Korean Society of Safety
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• v.10 no.1
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• pp.56-63
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• 1995

Two methods of the numerical method of CPQRA(Chemical Process Quantitative Risk Analysis) and the manual method of IAEA(International Atomic Energy Agency) were used to estimate the individual risk and societal risk around the chemical plant. Where, the CPQRA is introduced to verify the theoritical background of the manual of international atomic energy agency. The Gaussian plume model which has a weather stability class D with velocity of 5m/s was applied to calculate dispersion of hazard material. Also, 8-point method was employed to the effects of accidents for wind distribution. Furthermore, historical record, FTA(Fault Tree Analysis) and ETA(Event Tree Analysis) were used to estimate the probability or frequency of accidents. Eventually, the individual risk shows isorisk contour and the societal risk shows F-N curve around hazard facility, especially in chemical plants. Caulculated results, which both individual and societal risk, by using IAEA manual show simillar results to those of calculation by numerical method of CPQRA.

• Structural Engineering and Mechanics
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• v.66 no.1
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• pp.75-84
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• 2018

This study presents the reliability-based analysis of nonlinear structures using the analytical fragility curves excited by random earthquake loads. The stochastic method of ground motion simulation is combined with the random vibration theory to compute structural failure probability. The formulation of structural failure probability using random vibration theory, based on only the frequency information of the excitation, provides an important basis for structural analysis in places where there is a lack of sufficient recorded ground motions. The importance of frequency content of ground motions on probability of structural failure is studied for different levels of the nonlinear behavior of structures. The set of simulated ground motion for this study is based on the results of probabilistic seismic hazard analysis. It is demonstrated that the scenario events identified by the seismic risk differ from those obtained by the disaggregation of seismic hazard. The validity of the presented procedure is evaluated by Monte-Carlo simulation.

• Journal of the Korean Society of Safety
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• v.10 no.2
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• pp.97-104
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• 1995

To evaluate readily the effect of unconfined vapor cloud explosion(UVCE) having high possibility of accident and risk in chemical industries, the expert system of UVCE was developed and its applicability on a real accident was analyzed. We found that the hazard of UVCE could be well evaluated from the TNT equivalency model and the empirical loss data produced by overpressure for chemical facilities. By using the developed expert system, the size of vapor cloud, the quantity of vaporization, the released energy, the overpressure range from explosion point, and the impact damage of each installation could be estimated respectively. Also, probable maximum loss and catastrophic loss potential for real accident( cyclohexane release in Flixborough Nypro company) were estimated and compared with damages of the accident. As a result, the developed expert system could be well applicable to real accident.

• Journal of the Korean Society of Safety
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• v.27 no.5
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• pp.70-76
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• 2012

For the safe handling of n-tetradecane, the lower flash points and the upper flash point, fire point, AITs (auto-ignition temperatures) by ignition delay time were experimented. Also lower and upper explosion limits by using measured the lower and upper flash points for n-tetradecane were calculated. The lower flash points of n-tetradecane by using closed-cup tester were measured $104^{\circ}C$ and $112^{\circ}C$. The lower flash points and fire point of n-tetradecane by using open cup tester were measured $113^{\circ}C$ and $115^{\circ}C$, respectively. This study measured relationship between the AITs and the ignition delay times by using ASTM E659 apparatus for n-tetradecane. The experimental AIT of n-tridecane was $207^{\circ}C$. The calculated lower and upper explosion limit by using measured lower $104^{\circ}C$ and upper flash point $140^{\circ}C$ for n-tetradecane were 0.63 Vol.% and 3.18 Vol%.

• Journal of Dairy Science and Biotechnology
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• v.14 no.1
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• pp.1-15
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• 1996

With the starting of Uruguay Round(UR) and World Trade Organization(WTO), the direction of trade in world market has been setting up with the beginning of an opening age. However, world nations has been expressed a deep concern on the marketing and the circulations of unsafe foods, especially in the international trade of food products. Therefore, administration of most countries are taking a firm step on the safety of imported food products. The implementation of hazard analysis critical control point(HACCP) system in food industry is strongly appeared on the world stage at this point. Major international organizations, such as WHO, WTO, and EC have been recognized the importance of HACCP and already documented on their future plan for standardization of food safety in the international trade of food products by means of the this system. Several advanced countries have already developed HACCP system for the food industry and have been producing food products under this system. Now they have proposed rulemakings on a mandatory HACCP program in the production of domestic and imported food products. However, with the lacking of knowledge and information on the HACCP, there has been no actions for applying this system in the food industry of Korea. It is a very clear fact that Korean dairy and food industry will be faced on serious problems in exporting food products without applying HACCP system in the very near future. The objective of this article is to introduce the world trend. necessity, and application of HACCP system in food and dairy industry. Also a HACCP system developed by one dairy processing plant in Europe will be demonstrated as a moldel system.

• Journal of the Korean Society of Hazard Mitigation
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• v.2 no.1 s.4
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• pp.119-126
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• 2002

This paper presents the appropriateness for using high strength reinforcement according to the use of high strength concrete. Nine flexural tests were conducted on full-scale beam specimens according to the concrete strength, reinforcement strength and reinforcement ratio as main variable. The structural behavior was analyzed due to the flexural strength, stress-strain curve, deflections at yielding and fracture point, crack appearance and ductility factor. The member with high-strength reinforcements showed large deflection at yielding point and this was analyzed as a main cause to decrease the ductility factor. Structural behavior after yielding point, however, showed similarity to behavior of members with normal strength reinforcements of same stiffness. It was found that in the case of using reinforcements of $5500kgf/cm^2$ strength, the combination with concrete of $800kgf/cm^2$ strength demonstrated the great appropriateness which can increase the flexural capacity without any reduction of maximum reinforcement ratio.

• Journal of the Korean Institute of Gas
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• v.17 no.4
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• pp.9-17
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• 2013

Butanethiol is known as a typical odorant with hydrogen sulfide, methyl mercaptan, methyl sulfide, but on the physical and chemical properties and biological hazard assessment, including inhalation toxicity data are very scarce. Butanethiol as a colorless transparent liquid, and has physic-chemical characteristics with flash point as $-23^{\circ}C$ and strong fire risk, boiling point $84-85^{\circ}C$, vapor pressure 80.71 mmHg ($25^{\circ}C$), freezing point $-140.14^{\circ}C$. From whole body exposure with SD rats, the $LC_{50}$ is above 2,500 ppm (9.22mg/L), and then it is classified as the acute toxic chemical (inhalation) category 4 according to the governmental notification No. 2012-14.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.04a
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• pp.214-221
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• 2002

This study introduces a method to generate artificial earthquakes in Korean Peninsular using historical earthquake catalogues and point source model. For this purpose, three earthquake catalogues compiled by different researchers are compared to each other. And epicenters and magnitudes of future earthquakes are generated based on those catalogues. In generating ground motion accelertation, point source model proposed by Boore and Atkinson was adopted. Parameters of the model for South-Eastern part of Korean Peninsular was proposed by Noh and kn. From the epicenters, magnitudes, and ground motion models, possible earthquakes for 50,000 years are generated. Using these generated earthquakes ground accelrations and uniform hazard response spectra (UHRS) having 2%, 5%, and 10% exceedance probability in 50 years are proposed.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.783-786
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• 2008

The main goal of this study is to understand the effects of direct-runoff of chemistry and organic fertilizers which are adsorbing to sediment from farmland and non-point source discharge characteristics which are discharged to stream with soil erosion when rainfalls. pollutographs of TSS, BOD, COD, TN, and TP were measured for 10 rainfall events at watershed. EMC (Event Mean Concentration) were calculated for each rainfall event using quality and quantity measured. The result shows that the EMC ranges of 95% confidence intervals are 50.5-203 mg/L for TSS, 0.8-14.2 mg/L for $BOD_5$, 4.2-20.7 mg/L for $COD_{Mn}$, 0.2-0.5 mg/L for TP, 2.4-4.5 mg/L for TN, 1.36-3.04 mg/L for NO3--N, 0.13-0.42 mg/L for NH4+-N and 0.82-1.77 mg/L for TKN.

• Spatial Information Research
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• v.17 no.2
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• pp.243-249
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• 2009

Damages from typhoon events have contributed more than 60 percent of total economic and social loss and the size of loss have been increased up to 800 million dollars per year in Korea, It is therefore necessary to make an effort to mitigate the loss of natural disasters. To facilitate the evaluation of damages in advance and to support the decision making to recover the damages, scientific methods have been adopted. With the effort, GIS data can provide various tools. Three components of hazard mapping are estimation of hazard, inventory for vulnerable features, and fragility of each feature. Vulnerability of natural disaster can be obtained by relation between loss and meteorological data such as precipitation and wind speed. Features can be categorized from other GIS data of public facilities and private properties, and then social and economic loss can be estimated. At this point, GIS data conversions for each model are required. In this study, we build a method to estimate typhoon risk based on GIS data such as DEM, land cover and land use map, facilities.