• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2022.04a
• /
• pp.79-80
• /
• 2022

In December 2017, a fire at the Jecheon Sports Center caused 29 deaths and 40 injuries, and about 2 billion won in property damage. It is a facility used by unspecified people as a publicly used establishment with a piloti structure. The damage was expanded due to the ignition of combustible exterior materials, Lack of fire protection in horizontal and vertical penetrations. Although legislation has improved since the fire, it is not retroactively applied, increasing the risk of fire in existing buildings. Accordingly, it is necessary to examine the case of the Jecheon Sports Center fire and draw out the problems. In this study, the fire simulation results and the Jecheon Sports Center fire are comparatively analyzed and used as basic data for fire reduction measures in publicly used establishment. As a result of the fire simulation drive, in the case of the second floor, the room temperature exceeded the human life safety standard of 60 ℃ after about 700 seconds had passed. In the case of three floor, it is predicted that the indoor temperature will exceed about 350 ℃. and temporary complexation will occur in the indoor combustibles.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.28 no.6
• /
• pp.625-633
• /
• 2015

In this study, a coupled probabilistic framework is developed to assess wind risk on apartment buildings by using the convolution of wind hazard and fragility functions. In this framework, typhoon induced extreme wind is estimated by applying the developed Monte Carlo simulation model to the climatological data of typhoons affecting Korean peninsular from 1951 to 2013. The Monte Carlo simulation technique is also used to assess wind fragility function for 4 different damage states by comparing the probability distributions of the window system's resistance performance and wind load. Wind hazard and fragility functions are modeled by the Weibull and lognormal probability distributions based on simulated wind speeds and failure probabilities. The modeled functions are convoluted to obtain the wind risk for the different damage levels. The developed probabilistic framework clearly shows that wind risk are influenced by various important characteristics of terrain and apartment building such as location of building, exposure category, topographic condition, roof angle, height of building, etc. The risk model presented in this paper can be used as tools to predict economic loss estimation and to establish wind risk mitigation plan for the existing building inventory.

• Proceedings of the Korean Society of Agricultural Engineers Conference
• /
• 2005.10a
• /
• pp.661-666
• /
• 2005

Wastewater reuse are exposed public health risk by pathogens. Therefore, this study was examined for microbial risk assessment after irrigation as treated wastewater in paddy rice plots. Five treatments were used: biofilter effluent, UV disinfected water, pond treatment, wetland treatment and conventional irrigation water. Risk assessment was calculated based on the beta-Poisson model by concentration of E. coli from 2003 to 2005. Monte-Carlo simulation (n=10,000) was used to estimate the risk characterization of uncertainty. The risk range was from $10^{-5}$ to $10^{-8}$ except biofilter effluent was $10^{-4}$ in June. The USEPA(1992) has recommended that risk of < $10^{-4}$ is acceptable level of safety for potable waters. In 2005, risk value was lower than 2003, 2004 because of the first irrigation for plowing water is lower E. coli concentration used tap water. It is shown that the first irrigation water quality was important for wastewater irrigation in paddy. UV disinfection and natural treatment used pond and wetland were thought to be an effective for wastewater reuse.

• Journal of the Korea Institute of Building Construction
• /
• v.14 no.5
• /
• pp.443-449
• /
• 2014

Although risk reduction of construction projects have been continued, the risk of fatal accident has been increased. The purpose of this paper is to reduce the cause of the essential risk factors. Questionnaire survey of construction companies in domestic was conducted and the Multiple Regression Analysis of statistics program was used to grasp effective factors among the risk factors of construction companies in domestic. Development of the essential risk factors and its application to projects could lead to improvements such as compression of network, reduction of cost, improvement of quality and reduction of safety accident.

• Journal of the Korea Society for Simulation
• /
• v.28 no.3
• /
• pp.65-74
• /
• 2019

For many years, it has been widely studied on fork-join production systems but there is not much literature focusing on the finite buffer(s) of either individuals or shared, and generally distributed processing times. Usually, it is difficult to handle finite buffer(s) through a standard queueing theoretical approach. In this study, by using the max-plus algebraic approach we studied buffer-shared fork-join production systems with general processing times. However, because it cannot provide proper computational ways for performance measures, we developed simulation models using @RISK software and the expressions derived from max-plus algebra. From the simulation experiments, we compared some properties on waiting time with respect to a buffer capacity under two blocking policies: BBS (Blocking Before Service) and BAS (Blocking After Service).

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.189-189
• /
• 2000

A controller test on a sounding rocket using a testbed is discussed in the paper. Because of the high cost and the risk for the flight test the hardware simulation on the ground is performed. In this paper the conventional On/Off Controller is applied to the attitude control of a sounding rocket. The hardware simulation results are compared with those of the software simulation.

• 한국방재학회:학술대회논문집
• /
• 2008.02a
• /
• pp.513-516
• /
• 2008

The development of crash cushions is finally completed by full-scale vehicle crash tests. Since the current development of crash cushions is achieved by numerous repeated full-scale vehicle crash tests based on empirical and irrational methods, it requires a great amount of costs. In this research, the more rational procedure based on prototype design by static tests and computer simulation is suggested and it can minimize the number of full-scale vehicle crash tests.

• Journal of Korean Society of societal Security
• /
• v.2 no.1
• /
• pp.57-64
• /
• 2009

With the increase in construction of long railway tunnel, social interest in the railway tunnel fire risk has also increased. However, quantitative fire risk research on this topic is still lacking, especially in terms of consideration of uncertainty of each variables used in risk analysis. Hence, in this study, to improve the overall performance of fire risk analysis technique for railway tunnel, Monte-Carlo simulation method is added to the traditional probabilistic risk analysis based on event tree approach and its validity is investigated by applying it to the real railway tunnel project.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.4
• /
• pp.2933-2939
• /
• 2015

Premium rate should be applied the insurance objects are classified reasonably, depending on the degree of exposure to disaster risk. But the existing premium rate is applied same basic rate each cities and districts without the degree of exposure to disaster risk. In this study, we analyzed the exposure to flood risk using channel buffering and suggested way to classify the premium rate by reflecting the analysis results in order to improve its. It is determined that this study would contribute to calculate the storm and flood insurance basic rate reflected risk and make and analysis of flood risk of the local river that conditions of inundation simulation is insufficient.

• Environmental Analysis Health and Toxicology
• /
• v.12 no.3_4
• /
• pp.31-41
• /
• 1997

Public concerns about hazardous health effect from the exposure to organic by-products of the chlorination have been increased. There are numerous studies reporting that chlorination of drinking water produces numerous chlorinated organic by-products including THMs, HAAs, HANs. Some of these products are known to be animal carcinogens. The purpose of this study was to estimate health risk of DBPs by chlorinated drinking water ingestion in Seoul based on methodologies that have been developed for conducting risk assessment of complex-chemical-mixture. The drinking water sample was collected seperately at six water treatment plant in Seoul at March, April, 1996. In tap water of households in Seoul, DBPs were measured wilfh the mean value of 36.6 $\mu$g/L. Risk assessment processes,. which include processes for the estimation of human cancer potency using animal bioassay data and calculation of human exposure, entail uncertainties. In the exposure assessment process, exposure scenarios with various assumptions could affect the exposure amount and excess cancer risk. The reference dose of haloacetonitriles was estimated to be 0.0023 mg/kg/day by applying dibromoacetonitrile NOAEL and uncertainty factor to the mean concentration. In the first case, human excess cancer risk was estimated by the US EPA method used to set the MCL (maximum contaminant level). In the second and third case, the risk was estimated for multi-route exposure with and without adopting Monte-Carlo simulation, respectively. In the second case, exposure input parameters and cancer potencies used probability distributions, and in the third case, those values used point estimates (mean, and maximum or 95% upper-bound value). As a result, while the excess cancer risk estimated by US EPA method considering only direct ingestion tended to be underestimated, the risk which was estimated by considering multi-route exposure without Monte-Carlo simulation and then using the maximum or 95% upper-bound value as input parameters tended to be overestimated. In risk assessment for Trihalomethanes, considering multi-route exposure with adopting Monte-Carlo analysis seems to provide the most reasonable estimations.