• Journal of Korean Public Health Nursing
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• v.17 no.1
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• pp.96-112
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• 2003

The purpose of this study was to determine how often toddlers and preschoolers in kindergartens have accidents and what factors affect the accident rate. The study population consisted of 150 children who were attending at nursery schools and 150 children who were attending at kindergartens. The data was collected from ten nursery schools and five kindergartens from five districts in Daegu. The questionnaires were distributed to teachers of participating nursery schools and kindergartens to be completed using nursing care records in the institutions and by interviewing children's parents about all of the accidents happened in a previous year. Data were collected during the period of August 1 through 31, 2002. The results of the study are as follow: 1. Among 300 children, 282 had 506 accidental injuries during the study period. 2. The month, the day and the time with the highest accident rate were April. Monday, and between 2 and 4 o'clock in the afternoon, respectively. 3. Locations where the injury took place most included nursery schools or kindergartens, around the homes of the children, and inside the home. 4. Most accidents were occurred due to lack of carefulness of the children, and the most prevalent forms of injury was abrasions. 5. Most frequently injured part of the body was legs of the children. 6. Most injuries were healed within three days and required first aid measures to disinfect the wound. Mostly, these were performed by family members at home. Some children go to the hospital to suture the open wound. Most frequent type of complication was scar formation and the cost of the treatment ranged from 9,000 to 30,000 won. 7. Children's age. sex, birth order. personality. type of family composition. type of residency. father's occupation, father's age, and mother's age were significantly related to the frequency of injury among children. Children who were in nursery schools and kindergartens need their assessment for accident involving condition according to seasons, time. place. This study provided a very useful and important data to prepare accident prevention education program and accident prevention strategies, and to develop Injury Surveillance System.

• Nuclear Engineering and Technology
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• v.47 no.1
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• pp.26-32
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• 2015

During the course of a severe accident in a light water nuclear reactor, large amounts of hydrogen can be generated and released into the containment during reactor core degradation. Additional burnable gases [hydrogen ($H_2$) and carbon monoxide (CO)] may be released into the containment in the corium/concrete interaction. This could subsequently raise a combustion hazard. As the Fukushima accidents revealed, hydrogen combustion can cause high pressure spikes that could challenge the reactor buildings and lead to failure of the surrounding buildings. To prevent the gas explosion hazard, most mitigation strategies adopted by European countries are based on the implementation of passive autocatalytic recombiners (PARs). Studies of representative accident sequences indicate that, despite the installation of PARs, it is difficult to prevent at all times and locations, the formation of a combustible mixture that potentially leads to local flame acceleration. Complementary research and development (R&D) projects were recently launched to understand better the phenomena associated with the combustion hazard and to address the issues highlighted after the Fukushima Daiichi events such as explosion hazard in the venting system and the potential flammable mixture migration into spaces beyond the primary containment. The expected results will be used to improve the modeling tools and methodology for hydrogen risk assessment and severe accident management guidelines. The present paper aims to present the methodology adopted by Institut de Radioprotection et de $S{\hat{u}}ret{\acute{e}}$ $Nucl{\acute{e}}aire$ to assess hydrogen risk in nuclear power plants, in particular French nuclear power plants, the open issues, and the ongoing R&D programs related to hydrogen distribution, mitigation, and combustion.

• Journal of Korean Institute of Industrial Engineers
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• v.41 no.3
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• pp.296-304
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• 2015

Vessel Traffic Service (VTS) is the service that provides ships navigating on a sea transportation route with guidance and advice about geographical environment and other attentive information for their safety. In this study we point out that currently, constructing additional VTSs is required to prevent ships from unexpected accident on their navigation. We first select several candidate locations for constructing VTSs, based on the amount of marine transportation and its potential development possibility. Then, we present an optimization model in which the maximum area coverage is achieved by determining new locations of VTS subject to budget limitation. The problem can be modeled as a binary integer program and it provides an optimal solution for new VTS locations to be constructed under the consideration of the currently located VTSs in Korea.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.19 no.4
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• pp.117-122
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• 2011

EMSS is the organic system offering quick and efficient transfer and treatment for those who need an emergency service. For EMS aviation operation is the important transportation for the common benefits. There are several types of aviation operation. Among the different types of the operations, helicopter operation is very common because it is free from any locations. Notwithstanding the benefit, various types of EMS helicopter accidents and incidents are occurred because of its poor operation condition. In South Korea, even though so much effort was put to decrease the accidents rates, there are still many accidents happening by fire helicopters and the forest service helicopters. Therefore, in order to regularize the EMSH operation, measures for the aviation safety have to be prepared. This research is, related to the EMSH, focused on the suggestion of safety measure for the EMSH in Korea based on the accidents analysis in various countries.

• Nuclear Engineering and Technology
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• v.49 no.2
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• pp.434-441
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• 2017

Containment venting is one of several essential measures to protect the integrity of the final barrier of a nuclear reactor during severe accidents, by which the uncontrollable release of fission products can be avoided. The authors seek to develop an optimization approach to venting operations, from a simulation-based perspective, using an integrated severe accident code, THALES2/KICHE. The effectiveness of the containment-venting strategies needs to be verified via numerical simulations based on various settings of the venting conditions. The number of iterations, however, needs to be controlled to avoid cumbersome computational burden of integrated codes. Bayesian optimization is an efficient global optimization approach. By using a Gaussian process regression, a surrogate model of the "black-box" code is constructed. It can be updated simultaneously whenever new simulation results are acquired. With predictions via the surrogate model, upcoming locations of the most probable optimum can be revealed. The sampling procedure is adaptive. Compared with the case of pure random searches, the number of code queries is largely reduced for the optimum finding. One typical severe accident scenario of a boiling water reactor is chosen as an example. The research demonstrates the applicability of the Bayesian optimization approach to the design and establishment of containment-venting strategies during severe accidents.

• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.408-418
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• 2022

Marine accidents involving the entanglement of marine litter have continued to increase, with over 300 to 400 cases per year according to the statistical agency. Entanglement of marine litter may also lead to large-scale marine accidents which cause capsizing and sinking, thereby further causing detrimental casualties and material damages, and thus exceptional attention and care are required. In this study, Incheon, Busan, and Geoje and Tongyeong were found to be the high-frequency locations for accidents, which were selected by considering the ArcGIS analysis about the marine accidents of entanglement of marine litter and the occurrence frequency by the standard. The characteristics of the multiple accident areas involving entanglement of marine litter were the coastal cities where fishing facilities or marine leisure related conditions were activated, with the port which handles much of the traffic of outbound and inbound vessels located nearby. Marine plastic pollution impacts not only the marine ecosystem and food chain, but also the hull and engine of ships, and may further pose threats to the safety of vessels and crews. It is necessary to find a common link between the relevant areas and to strive to remove the root causes of marine accidents by reducing marine litter.

• Journal of the Korean Society of Safety
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• v.33 no.6
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• pp.144-156
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• 2018

Level 3 Probabilistic Safety Assessment (PSA) is performed for the risk assessment that calculates radioactive material dispersion to the environment. This risk assessment is performed with a tool of MELCOR Accident Consequence Code System (MACCS2 or WinMACCS). For the off-site consequence analysis of multi-unit nuclear power plant (NPP) accident, the single location (Center Of Mass, COM) method has been usually adopted with the assumption that all the NPPs in the nuclear site are located at the same COM point. It was well known that this COM calculation can lead to underestimated or overestimated radionuclide concentration. In order to overcome this underestimation or overestimation of radionuclide concentrations in the COM method, Multiple Location (ML) method was developed in this study. The radionuclide concentrations for the individual NPPs are separately calculated, and they are summed at every location in the nuclear site by the post-processing of radionuclide concentrations that is based on two-dimensional Gaussian Plume equations. In order to demonstrate the efficiency of the ML method, radionuclide concentrations were calculated for the six-unit NPP site, radionuclide concentrations of the ML method were compared with those by COM method. This comparison was performed for conditions of constant weather, yearly weather in Korea, and four seasons, and the results were discussed. This new ML method (1) improves accuracy of radionuclide concentrations when multi-unit NPP accident occurs, (2) calculates realistic atmospheric dispersion of radionuclides under various weather conditions, and finally (3) supports off-site emergency plan optimization. It is recommended that this new method be applied to the risk assessment of multi-unit NPP accident. This new method drastically improves the accuracy of radionuclide concentrations at the locations adjacent to or very close to NPPs. This ML method has a great strength over the COM method when people live near nuclear site, since it provides accurate radionuclide concentrations or radiation doses.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.4
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• pp.1279-1287
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• 2014

The purpose of this study is to develop the U-turn accident model at signalized intersections in urban areas. The characteristics of the accidents which are associated with U-turn operation at 3 and 4-legged signalized intersections was analyzed and the U-turn accident model was developed by regression analysis in Changwon city. First, in order to analyze the effectiveness on traffic accidents by U-turn installation, the difference of mean of traffic accident number are measured between two groups which are composed by whether or not U-turn installation the groups by Mann-Whitney U test. The result of significance test showed that intergroup comparison on mean by accident types made difference except rear-end accident type and by accident locations exit section only showed difference in significance level at 4-legged intersections, so the accident number have more where the U-turn is permitted than not. Response measures about the number of accidents were classified by whether accidents occurred and accident model were constructed using binomial logistic regression analysis method. The developed models show that the variables of conflict traffic, number of opposing lane are adopted as independent variable for both intersections. The variables of longitudinal grade for 3-legged signalized intersection and number of crosswalk for 4-legged signalized intersection at which the U-turn is permitted is adopted as independent variable only. These study results suggest that U-turn would be permitted at the intersection where the number of opposing lane is more than 3.5 each, the longitudinal grade of opposing road is upward flow and there is need to establish the U-turn traffic sign at signalized intersections.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.2
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• pp.33-43
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• 2022

The number of car crashes increases along with the increasing number of vehicles. Hence, diverse initiatives on traffic accidents have been implemented, targeting zero crash fatalities. According to the 3rd Traffic Safety Master Plan of 2016, the current standard selecting road accident black spots prioritizes locations with the high cumulative death toll. While this standard is suitable for roads that a city government manages to some extent, it is not suitable for roads less than 20 meters that a borough (Gu) handles. The roads under the supervision of a borough do not have enough death toll, and thus improvements on its road accident black spots are highly limited. In addition, discovering the causes of traffic accidents is not easy when the number of car accidents is obtained by considering only fatal accidents, which are relatively low in number. Therefore, including all traffic accidents might identify causes of accidents and result in better advancements. Therefore, this research follows rational decision-making and suggests new National Traffic Safety Master Plan standards. These new standards are obtained by comparing accident costs between the location of fatal crashes and road accident black spots. The analysis result shows that considering all types of accidents yields better results. For example, a Three-way Intersection in front of Zion Day Care Center, one of the selected spots under the current standard, has lower road crash costs than Sinchon Intersection, a selected spot under a new standard. Therefore, the study concludes that the standards to select road accident black spots need to include traffic accident severity and road crash costs.

• Journal of Korean Public Health Nursing
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• v.12 no.1
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• pp.55-74
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• 1998

In the past most major accidents resulted in death, but today there is a dramatic increase in the number of people who survive such accidents but who are left with permanent injury. Particularly, children who are inquisitive about their surroundings but immature in their ability to assess danger, are more vulnerable to accidents and their causes as well as to determine attitudes towards prevention. The main objective of the study was to assess the effectiveness of using an accident prevention manual for accident for accident prevention education. The study was a quasi-experimental study using a questionnaire format. The subjects of the study were 393 mothers of children attending six day care centers in Seoul. Data collection was done between May 1 and June 15, 1997. The tools used for the study were a questionnaire developed the researchers and a manual for accident prevention. The collected data were analyzed using SPSS. The results of the study are as follows: 1. Types of accidents included stabbing, bums, falls from heights, choking, falls on slippery surfaces, traffic accidents, drowning, poisoning, and electrical shock in that order of frequency. 2. The main causes of accidents in children were from cosmetics and household medications. 3. The most frequent locations of accidents in the home were the bathroom, kitchen, and stairways in that order. 4. For $90.4\%$ of children safety seats were not used when the ridding in a car. 5. In examining the parents' accident prevention practices, it was found that many parents used only . one electrical outlet for many appliances, tending to overload the electricity lines and that they were not practically concerned bout the flammability of children's pajamas, indicating a less than positive attitude towards fire prevention. 6. The parents had not provided their children with any instruction on accident prevention or on what to do after an accident had occurred. 7. After the use of pamphlet in an accident prevention education program, it was found that there was a statistically significant difference in the degree to which children carried out safety measures (t=14.96, p=.000) and in their safety habits (t=-1.67, p<.1) indicating an effectiveness in this method of education. The results of this study showed that there are many things in a child's environment that can cause accidents and that the possibility of an accident occurring is high. So nurses looking after children should be aware of the need for safety education to prevent accidents in the home and plan to provide appropriate educational material to help parents with this education.