• Journal of the Korean Society for Precision Engineering
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• v.15 no.4
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• pp.51-57
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• 1998

It is common to assume identical allowable safety factors in static strength defined by mean stress and in fatigue, defined by stress amplitude. Under the load with asymmetrical cycles the safety factor is not the same. In this paper, with the consideration of unequal allowable safety (actors a general method for estimating fatigue reliability of a machine element under a combined state of stress is derived based on the theory proposed by Prof. Kececioglu and a normal distribution. The calculation of fatigue reliability fur limited life is discussed with example.

• Journal of the Korea Safety Management & Science
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• v.16 no.3
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• pp.145-154
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• 2014

Performance based design(PBD) is the method to make a fire safety design against them after predicting the factors of fire risk in a building. Therefore, predicting fire risk in a building is very important process in PBD. For predicting fire risk of a building, an engineer of PBD must consider various factors such as ignition location, ignition point, ignition source, first ignited item, second ignited item, flash over, the state of door and fire suppression system. But, it is difficult to trust fire safety capacity of the design because the process in Korea' PBD is unprofessional and unreasonable. This paper had surveyed some cases of PBD that had been made in Korea to find the problems of the process to predict fire risk. And it have proposed the improvements of process to predict fire risk of a building.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1569-1570
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• 2015

몰드변압기는 유입변압기와 달리 구조적으로 복잡하고 밀폐된 구조로 되어 있어서 사용기간 동안 고신뢰성을 확보하기 위해서 예방진단기술이 필요하다. 그러나 공장이나 빌딩 현장에서 몰드변압기의 열화상태 관리하는 방법은 온도관리, 소음진동관리 등의 수준으로 활선상태에서 사고를 예측하기에는 많은 한계가 있다. 이러한 문제점을 해결하고자 본 논문에서는 몰드변압기의 부분방전 측정을 중심으로 활선상태에서 열화 진단기술이 중요하다. 특히, 몰드변압기의 절연열화 진단을 위해서 상호보완적인 측정방법이 필요하고, 몰드변압기의 절연상태의 유무를 판정할 수 있는 분석방법을 개발하고자 하였다.

• Nuclear Engineering and Technology
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• v.46 no.5
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• pp.707-718
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• 2014

As a result of conducting a 45 minute-long seminar on the principles, state of use, advantages, and disadvantages of nuclear power generation for Korean elementary, middle, and high school students, the levels of perception including the necessity (p<0.017), safety (p<0.000), information acquisition (p<0.000), and subjective knowledge (p<0.000), objective knowledge (p<0.000), attitude (p<0.000), and behavior (p<0.000) were all significantly higher. This indicates that education can be effective in promoting widespread social acceptance of nuclear power and its continued use. In order to induce behavior change toward positive judgments on nuclear power generation, it is necessary to focus on attitude improvement while providing the information in all areas related to the perception, knowledge, attitude, and behavior. Here, the positive message on the convenience and the safety of nuclear power generation should be highlighted.

• Journal of the Korea Safety Management & Science
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• v.15 no.1
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• pp.121-132
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• 2013

The objective of this study is to maintain the same frequency as the electrode material, concentration, duration of decomposition efficiency, power consumption and voltage measurements using a composite catalyst according to the change of process parameters to obtain the optimum state of the process and the maximum decomposition efficiency. In this paper, known as a major cause of air pollution, such as NO, NO2, SO2, frequency, flow rate, concentration, the material of the electrodes, and using TiO2 catalyst reactor with surface discharge caused by discharging the reactor plasma NOx, SOx decompose the harmful gas want to remove.

• Journal of the Korea Safety Management & Science
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• v.8 no.2
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• pp.13-23
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• 2006

The present study has investigated the patterns and the causes of safety -accidents on the accident-data in semiconductor Industries through near miss report the cases in the advanced companies. The ratio of incomplete actions to incomplete state was 4 to 6 as the cases of accidents in semiconductor industries in the respect of Human-ware, Hard- ware, Environment-ware and System-ware. The ratio of Human to machine in the attributes of semiconductor accident was 4 to 1. The study also investigated correlation among the system related to production, accident, losses and time. In semiconductor industry, we found that pattern of safety-accident analysis is organized potential, interaction, complexity, medium. Therefore, this study find out that semiconductor model consists of organization, individual, task, machine, environment and system.

• Journal of the Ergonomics Society of Korea
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• v.20 no.2
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• pp.99-111
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• 2001

Human factors is a key issue in the maritime industry including ship design and navigation safety. Human factors for ship design is to optimize safety and convenience of crews and passengers. And human factors for navigation safety is to minimize marine accident occurrence by human and organizational error. There are several technical requirements to incorporate human factors and marine system Risk analysis. human behaviour analysis and human M&S(modeling and simulation) are examples of technical requirements. This paper provides the key issues and technologies of human factors for ship design and navigation safety.

• Wind and Structures
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• v.24 no.3
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• pp.249-265
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• 2017

An efficient and accurate algorithm is proposed to estimate flutter safety factor of suspension bridges satisfying prescribed reliability levels. Uncertainties which arise from the basic wind speed at the bridge deck location, critical flutter velocity, the wind conversion factor from a scaled model to the prototype structure and the gust speed factor are incorporated. The proposed algorithm integrates the concepts of the inverse reliability method and the calculation method of the critical flutter velocity of suspension bridges. The unique feature of the proposed method is that it offers a tool for flutter safety assessment of suspension bridges, when the reliability level is specified as a target to be satisfied by the designer. Accuracy and efficiency of this method with reference to three example suspension bridges is studied and numerical results validate its superiority over conventional deterministic method. Finally, the effects of various parameters on the flutter safety factor of suspension bridges are also investigated.

• Journal of the Korean Society of Safety
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• v.23 no.5
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• pp.79-83
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• 2008

The corrugated stainless steel tubing(CSST) for the fuel gas piping system can be installed easily and quickly. It is often constructed under the ceiling and the wall which has a good flexibility and installation in comparison with iron pipe. However, the quality of the CSST is determined to depend upon the welding skill of stainless steel tubing. In this study, it is tested by controlling jet point of Ar as inert and cooling gas, and also compared with the bead state of welding point and the performance. As a result, it has the best condition when the jet point of Ar is located behind $5{\sim}10mm$ of the welding point.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.26 no.4
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• pp.149-154
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• 2018

Risk Based Oversight is a way of performing oversight, where planning is driven by the combination of risk profile and safety performance. Risk Based Oversight enables prioritization and allocation of State's safety management resources commensurate with the safety risk profile of each service provider. This paper presents the concept of Risk Based Oversight and applies it to the current Korean aviation safety oversight process. In particular, this study presents a method for generating operating profiles, one of the key concepts of Risk Based Oversight. Operations Specifications of Part 121 Airlines can generate operating profiles. In this study, a practical study was conducted to generate the operating profile and scoped DCTs using Part 121 Airlines's Operations Specifications.