• Nuclear Engineering and Technology
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• v.18 no.3
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• pp.200-208
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• 1986

The loss of coolant accident based on a double-ended cold leg break is analyzed with the discharge coefficient (Ca) of 0.4. This analysis covers the whole transient period from the start of depressurization to the complete refilling of the core by using RELAP4/MOD6-EM and RELAP4/ MOD6-HOT CHANNEL for the system thermal-hydraulics and the fuel performance during the blowdown phase respectively, and RELAP4/MOD6-FLOOD and TOODEE2 during the reflood phase. A simple analytical method has been developed to account for the lower plenum filling by approximating steam-water countercurrent flows and superheated wall effects at the downcomer during the refill period. Based on the informations. at the time of EOB (end-of-bypass), the refill duration time and the initial reflooding temperature were estimated and compared with the results from the RELAP4/MOD6, resulting in a good agreement. In addition, some parametric studies on the EOB were performed. The form loss coefficient between upper head and upper downcomer was found to be sensitive to the occurrence of the spurious EOB. Appropriate form loss coefficients should be taken into account to avoid the flow oscillations at the downcomer. The analyses with the six and three volume core nodalizations, respectively, show much similar trends in the system thermal-hydraulic performance, but the former case is recommended to obtain good results.

• Journal of Digital Convergence
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• v.15 no.11
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• pp.245-250
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• 2017

Flash floods is defined as the flooding of intense rainfall over a relatively small area that flows through river and valley rapidly in short time with no advance warning. So that it can cause damage property and casuality. This study is to establish the flash-flood warning system using 38 accident data, reported from the National Disaster Information Center and Land Surface Model(TOPLATS) between 2009 and 2012. Three variables were used in the Land Surface Model: precipitation, soil moisture, and surface runoff. The three variables of 6 hours preceding flash flood were reduced to 3 factors through factor analysis. Decision tree, random forest, Naive Bayes, Support Vector Machine, and logistic regression model are considered as big data methods. The prediction performance was evaluated by comparison of Accuracy, Kappa, TP Rate, FP Rate and F-Measure. The best method was suggested based on reproducibility evaluation at the each points of flash flood occurrence and predicted count versus actual count using 4 years data.

• Journal of the Korean Institute of Gas
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• v.22 no.5
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• pp.1-17
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• 2018

Related incidents and accidents are frequent after 2000 years, such as the outbreak of the Taian peninsula crude oil spillage and Gumi hydrofluoric acid leakage accident. In the wake of such environmental pollution accidents, Consensus has been formed to enact legislation on liability for the compensation of environmental pollution in 2014 and the rescue, and has been in force since January 2016. Therefore, in the domestic insurance industry, the introduced environmental liability insurance system needs to be managed through the standardization formula of a new insurance model for managing the environmental risk. This study has been carried out by the emergence of a safe insurance model with a risky nature of the risk type, which is one of the services of the knowledge base. The verification of the six assurance media on the occurrence of environmental pollution such as chemical, waste, marine, soil, etc. is expressed through semantic interoperability through this possible ontology. The insurance model was designed and presented by deducing the relationship between the amount of money and the amount of money that was written in the area of existing expertise, In order to exclude the possible consequences, the concept of abstract is conceptualized in the form of a customer, and a plan for the future development of an ontology-based decision support system is proposed to reduce the cost and resources consumed every year. It is expected that standardization of the verification standard of the mass of mass will minimize errors and reduce the time and resources required for verification.

• Journal of the Korean Institute of Gas
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• v.22 no.4
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• pp.74-81
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• 2018

The Korean Government has proceeded petroleum gas pipeline construction business since 2014 for rural districts. The operating pressure of petroleum gas pipeline are from 25kPa to 75kPa which are different from that of natural gas pipeline. Petroleum gas pipeline pressure is ten or forty times higher than natural gas operating pressure. For this reason, petroleum gas pipeline has higher probability of accident occurrence from massive gas leakage. Korea Gas Safety Corporation begins to development excess flow valves and their performance testing equipment since 2017. The excess flow valves stop the gas flow when a overflow happened in gas pipeline. The excess flow valves are generally not installed in main pipeline, because that may block massive gas supply. So, the valves are installed in starting points of branch pipes. According to the number of house and amount of gas use, a shut-off point of exxcess flow valve is determined called as Trip Flow. The trip point is the most important thing of excess flow valve, so, it is required a equipment testing the performances of excess flow valve as trip point.

• Journal of Korean Physical Therapy Science
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• v.6 no.1
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• pp.905-913
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• 1999

The hand is a part of the body which has various functions and a sophisticated structures bone, Joint, tendon, ligament and logical nerve organ are aggregated densely in the hand of anatomy its functions are delicate. The hand's functions are very important for doing ADL and a worker's As the hand is structure which is used often and commonly it is a site that can be easily damaged by a accident on work. This study was investigated and analyzed by the results from 238 workers who had hand injury and physical therapy from January, 1997 to June, 1998 at Shin-Pung, Jang-Lim industrial complex which is located in Pusan. 1. A hand injury most frequertly happened in worker in their 30's and 20's(66 case, 28%), second was 57 case(24%) their 40's. 2. Among workers suffering from injury, who had one or less than 2 years on the job, a injury most frequently occurred. 3. Scale of workers, A injury most frequently happend in a place where had workers from 10 to 50. 99 workers from that place were 42% of total. 4. Month of occurrence rate in March were the highest compared to other months 40 injury workers in march were 17% of the total. Second was July, and the least was April that injury appeared with 10 workers. (4.2% of the total) 1. Frocture was the most common lesion 82 workers had that lesion(34%) soft tissue rupture was 71 workers who were 30% of total in type of lesion. 2. Of the site of lesion multiple case was the most common in which 57 workers had that lesion it were 24% of the total. The next was the index finger site in which 44 workers were 19% of the total. The index finger was the most common mono-site that can be lesion 36 workers were the middle finger lesion workers who were 15% of the total. Of the joint lesion, PIP was the most in which 76 workers were 44% and in MC 27 workers were 15% of the total. 3. Interval of physical therapy 79 workers from one month to 2 months, was 33% of the total and 174 workers who had therapy below 3 months were 71% 4. Post injury of disablity of the site, phalangeous disability was the most in which 148 workers had that injury and they were 62% of the total of the grade of disability 110 workers who were 46% of the total state from less than 25% disability in hand-function and 59 patients who were 25% had no disability. There were 6 workers (3% of the total) who had over -75%-dibability in the hand-function.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.5
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• pp.1115-1125
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• 2009

Purpose: The purpose of this study was to investigate the Safety-practice and Its Related Factors among Elementary students in rural area, to provide the basic data for prevention for safety accident occurrence in order to improve the QOL. Methods: The subjects of this study were 549 elementary students using self-report questionnaires. The collected data was analyzed using descriptive statistics, t-test, ANOVA, Scheffe's test, Pearson correlation coefficient and stepwise multiple regression with SPSS 12.0 Program. Results: The mean score for level of the safety awareness was 3.55(${\pm}.36$) and of the safety practice, 2.98(${\pm}.48$). The score of Safety-practice was statistically significant difference according to students' gender(p= .028) and students' grade(p= .004), the number of friends(p= .002), the level of school life adaptation(p= .000), recognized learning proficiency(p= .000), personality(p= .005), curiosity(p= .003), the level of demand for safety education(p= .000), the level of safety-education conducted by parents(p= .000), the level of safety-education conducted by teacher(p= .000). Stepwise multiple regression analysis for Safety-practice revealed that the most powerful predictor was level of Safety-awareness and self-esteem, the level of safety-education conducted by parents explained 28.8% of the variance. Conclusions: Therefore, it is necessary to develop safety practice promotion program in order to enhance the quality of life of elementary students. Future studies need to be pursued to find various variances.

• Journal of the Korean Society of Hazard Mitigation
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• v.3 no.1 s.8
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• pp.149-155
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• 2003

The reason of source for a tragic death by the occurrence of an event is $\ulcorner$unobservant of safety rule,$\lrcorner$ $\ulcorner$negligence of staff,$\lrcorner$ $\ulcorner$deficiency of responsibility$\lrcorner$ and $\ulcorner$deficiency of safety value$\lrcorner$ and for certain reason that is insufficiency of space for safety education also think little of a people, unobservant of safety rule, selfishness and so on. It makes new and specific plan that is simulation room before I compare the inside and outside of the country for a nation the reform of consciousness. Next, go ahead with a plan for about safety-simulation room. The Government can support to plan if it make a proposal to center of Government. It should be make a people of safety system, and it build the safety-simulation room $1{\sim}2$ in the city or county. And, the city cannot build the big safety-simulation room the reason are size of building and money. Accordingly, it will be make a system and installation for different type of safety-simulation room for about calamity, disaster and different type of accident in Korea. It must be build the building of space that should be make a space of knowledge and information by many books and media, develop of education program from life-safety.

• Journal of Navigation and Port Research
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• v.32 no.8
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• pp.569-576
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• 2008

By the development of international trade in last decades, Korean International Trade has been grown rapidly and Korean Port and Port facilities have been improved stimultaneously: finally volume of the marine traffic increased rapidly. Presently, 15 VTS centers have serving in Korean waters and since the introduction of the first VIS Center in Korea there is no quantitative analysis to find workload of VIS operator. After that Port-MIS and De-brief data have been gathered for 7 days and inbound-outbound vessels time-g/t table prepared and traffic volume examined for each V1S center. Hence $L^2$ conversion traffic volume and dangerous vessel ratio obtained Later on conversion controlled number obtained by denoting ratio 1.0 to directly controlled vessels by VTSO and denoting ratio 0.3 to indirectly controlled vessels by VTSO. Traffic volume, large vessel ratio, dangerous vessel ratio, dimension of VTS controlled area, marine accident occurrence frequency and communication volume of comm. log can be counted as a factor which influence to workload of VTSO. All those factors have been examined and analyzed. Finally, ship's size and dangerous vessel ratio have been chosen to derive the Number of composite conversion control for workload formula.

• Journal of Navigation and Port Research
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• v.44 no.4
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• pp.275-282
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• 2020

Recently, the occurrence of a ship capsizing was analyzed as the main cause of the lack of stability or loss because of the improper management of the center of gravity, the movement of cargo or heavy weight when excessive steering occurs or when navigating during bad weather. Thus, to prevent a ship from capsizing, it is necessary to secure stability to enable the ship's return to its upright position, even if a dangerous heel occurs. The GM is a crucial evaluation factor regarding stability, which the navigation officer uses to preserve stability. In this study, based on the stability data collected from the operating of ships for five years, The GM by ship's type according to the operating status was analyzed specifically such as a ship's length, breadth, and gross tonnage. The feature of the GM distribution according to a ship's length was confirmed, and after performing the correlation analysis between the breadth and the GM, the ratio of the GM to breadth was calculated, and the result was compared with the previous ratio. Additionally, a simple approximation formula and minimum GM for the estimation of the GM by ship type were proposed by the regression analysis of the GM using the gross tonnage (GT)/breadth (B) to reflect the trend of larger ships being built. The results of this study are expected to be used as data for the review of securing a stable GM on ships.

• Journal of the Korea Convergence Society
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• v.8 no.5
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• pp.61-68
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• 2017

This study investigates the differences in medical practices and medical cost according to auto insurance companies based on 8,589,602 cases that were treated by auto insurance corporation for the year of 2015, from the beginning of January to the end of December. The results of this study can be summarized following. First, in terms of the general characteristic in medical treatment, especially the age, the highest figure in both non-life insurance and mutual aid cooperative was shown in the age of 50 to 59 at 22.8 per cent(p<0.001). Second, in terms of a medical cost per a hospital care, classified by clinic, the costs in the department of internal medicine were much higher than those in the surgical department, and the thoracic surgery among parts of the surgical department showed the highest figures in both non-life insurance and mutual aid cooperative. According to the above summarized results of this study, it can be concluded that Health Insurance Review and Assessment Service has to address the problem on the increase of unnecessary costs and the occurrence of social expenses caused by the delay of patients' rehabilitation and return to their daily lives, by carrying out the evaluation for the appropriateness to organizations that ask for payments of auto insurance.