• Journal of Korean Society of Industrial and Systems Engineering
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• v.19 no.37
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• pp.31-40
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• 1996

The amount of safety stock is decided from various information such as the forecasted demand, the lead time, the size of the order quantity and the desired service level. There are two cases to consider the problem of setting safety stock when both the demand in a period and the lead time are characterized as random variables: the first case is the parameters of the demand and lead time distributions are known, the second case is they are unknown and must be estimated. The objective of this study is to present the procedure for setting safety stocks in the case the parameters of the demand and lead time distributions are unknown and must be estimated. In this study, a simple exponential smoothing model is used. to generate the estimates of demand in each period and a discrete distribution of the lead time is developed from historical data, and the optimal service level is used which determined to consider both of a backorder and lost sale.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.2074-2075
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• 2007

본 연구에서는 침수된 저압 지중함에서 발생될 수 있는 누전 사고시 지중함내의 접지조건이 주변의 대지전위분포에 미치는 영향을 고찰하였다. 저압 지중함 실증실험장을 설계 구축하였으며 3가지 접지조건의 경우에 대해 대지전위 측정 실험을 실시하였다. case 1과 case2와 같은 실증실험을 통해 저압 지중함에 설치되어 있는 접지선은 저압 지중함에서 대지전위 분포에 거의 영향이 없음을 확인하였으며, case 3과 같은 실증실험을 통해 저압 지중함 철재틀에 접지단자를 본딩 할 경우 저압 지중함 주변의 대지전위 상승이 거의 발생되지 않음을 확인하였다. 따라서 저압 지중함 철재틀에 접지단자를 본딩 할 경우 혹시 발생될 수 있는 지중함의 누전에 의한 감전사고를 매우 효과적으로 방지할 수 있을 것이다.

• Journal of the Korean Society of Safety
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• v.32 no.2
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• pp.27-33
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• 2017

This study is intended to identify issues on the basis of investigating the actual state of laboratory environment and outlet circuit, and derive end states by expressing sequences from the initiating event of disaster to accident in leakage current, poor contact and overload through ETA(event tree analysis). To this end, this study investigated the actual state of electric equipment of laboratory at universities in all parts of country. And it is shown that most of them are failure in electric work and user negligence in the investigation of actual state. It is found that there is earth fault and defect in wire diameter in the failure of electric work and the problem of partial disconnection due to wire bundling and poor contact in user negligence. Outlet-related component, failure rate and initiating events are composed of a total of 41 initiating events, i.e., 30 internal initiating events and 11 external initiating events. And end states are composed of a total of 15 parts, i.e., 3 electric power parts and 12 safety parts. Earthing class 3 is the most important safety device against leakage current (initiating event). And in case of poor contact, it is necessary for manager to check thoroughly because there is no safety device. In case of overload/overcurrent, when high-capacity equipment is connected, a molded case circuit breaker, safety device, worked. However, in most cases, it is verified that this doesn't work. This study can be utilized as electric equipment safety guide for laboratory safety manager and managers.

• Economic and Environmental Geology
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• v.56 no.5
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• pp.565-580
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• 2023

In this study, we reviewed and summarized comprehensive roles and importance of natural analogue studies for demonstrating the safety and improving the reliability of the safety for the deep geological disposal of high-level radioactive waste. We also investigated domestic and foreign status of natural analogue studies in order to study and substantiate complex and various radionuclide behaviors in subsurface disposal environments. In addition, we investigated and uranium behaviors in groundwater and rock in uranium deposits including domestic uranium deposits in Ogcheon Metamorphic Belt and biogeochemical interactions in geological environments. Although there are many limitations and uncertainties in directly using the information and data for uranium behaviors obtained from uranium deposits in the disposal safety assessment, the information and data can be utilized in the disposal safety assessment and safety case construction both in qualitative and partly quantitative ways.

• IE interfaces
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• v.15 no.2
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• pp.114-125
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• 2002

The objective of this paper is to describe a systematic accident scenario analysis method(SASA) adept at creating accident scenarios for the design of safer products. This approach was inspired by the Quality Function Deployment(QFD) method, which is conventionally used in quality management. In this study, the QFD provides a formal and systematic scheme to devise accident scenarios while maintaining objectivity. SASA consists of three key stages to be broken down into a series of consecutive steps:(1) developing an accident analysis tableau,(2) devising the accident scenarios using the accident analysis tableau,(3) performing a feasibility test, a clustering process and a patterning process, and finally(4) performing quantitative evaluation of each accident scenario. The SASA was applied to a case study of child safety seats. The accident analysis tableau devised 2828(maximum) accident scenarios from all possible relationships between the hazard factors and situation characteristics. Among them, 270 scenarios were devised through the feasibility test and the clustering process. The patterning process reduced them to 29 patterns representative of all accident scenarios. Based on an intensive analysis of the accident patterns, design guidelines for a safer child safety seat were recommended. The implications of the study on the child safety seat case were then discussed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.5342-5348
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• 2014

Slope stability analyses were conducted to investigate the limitations of application of the standard inclination of slope and the effects of the berm width on the slope stability. The standard slope inclination could be applied to the basic slope sections that were considered for the analyses, whereas additional slope stability analysis should be performed for the case of considering ground water. A comparison of the factors of safety between the case of installing a berm and the case of letting the grading have an equivalent section area with the case of installing the berm, the factors of safety in the case of installing a berm were greater than those for the case of allowing grading, and the differences between the factors of safety increase with increasing berm width. For all the sections considered in the analyses, the increments of the safety factor were proportional to the width of the berm and those corresponding to the embankment slope and cut slope with a berm width of 7m were 34.5% and 48%, respectively.

• Proceedings of KOSOMES biannual meeting
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• 2018.06a
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• pp.117-117
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• 2018

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.spc
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• pp.63-74
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• 2020

The operational safety assessment is an important part of a safety case for the deep geological repository of spent fuels. It consists of different stages such as the identification of initiating events, event tree analysis, fault tree analysis, and evaluation of exposure doses to the public and radiation workers. This study develops a probabilistic safety assessment method for the operational safety assessment and establishes an assessment framework. For the event and fault tree analyses, we propose the advanced information management system for probabilistic safety assessment (AIMS-PSA Manager). In addition, we propose the Radiological Safety Analysis Computer (RSAC) program to evaluate exposure doses to the public and radiation workers. Furthermore, we check the applicability of the assessment framework with respect to drop accidents of a spent fuel assembly arising out of crane failure, at the surface facility of the KRS⁺ (KAERI Reference disposal System for SNFs). The methods and tools established through this study can be used for the development of a safety case for the KRS⁺ system as well as for the design modification and the operational safety assessment of the KRS⁺ system.

• Child Health Nursing Research
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• v.15 no.2
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• pp.145-154
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• 2009

Purpose: The purpose of this study was to develop a guide book on safety education for teachers to use in education classes for elementary school students. Methods: Dick & Carey's teaching model and Keller's ARCS theory were used in the development of this guide book. Results: This guide book was developed for lower grade (1st$\sim$3rd) and higher grade (4th$\sim$6th) elementary school students. The content consisted of subjects, worksheets, content for teachers, statistical data, case studies, and a safety letter to the parents. The 10 subjects were as follows: "Importance of injury prevention", "Safety at home", "Accident prevention at school", "Violence prevention", "Vehicles safety", "Water safety", "Prevention of Fires & Burns", "Safety of Toys & home supplies", "Safety in Sports & Recreation activity", "Prevention of injury caused by animals". Statistical data was presented by graphs and case studies were presented of cases of real occurrences of accidents. Worksheets contain various activities for students. Safety letters were composed for each student's parents. Conclusion: This guide book presents effective material for safety education classes in elementary school and the authors hope it will be widely used in elementary schools.

• Journal of the Korea Safety Management & Science
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• v.15 no.2
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• pp.39-45
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• 2013

Occupational injury rate of Korea recently slides slightly downward after stagnating around 0.7%'s for more than 10 years. To accelerate this trend, injury prevention for small enterprises is crucially important because vast majority of injuries take place in small enterprises. Considering huge number of small enterprises, we need to focus our efforts to type of riskier industries. By analysing detailed injury data, we select type of industries which need our concentrated prevention efforts. Several preventive measures are recommended, after we made literature survey of case studies for small enterprises. The result identifies riskier type of industries including transportation machinery manufacturing industry type(B), woods & veneer manufacturing industry, etc. Safety of machinery, new enterprises less than 2 years in service and new employees serving less than 6 months are in need for focused prevention efforts. To cope with these vulnerable spots, recommended preventive measures include strengthening of machinery safety standards, early assistance for safety to new enterprises, mandatory safety education before employment, etc.