• 한국산업보건학회지
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• 제17권2호
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• pp.120-130
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• 2007

A oxygen generating closed-circuit SCBA for escape from fire will be newly developed and then a program for estimating service time for it should be required. A SCBA made on an experimental basis consisted of five components such as half facepiece (mask), $KO_2$ box, oxygen reservoir, $CO_2$ remover and hood. The half mask had a good fitting performance since fit factors for 10 subjects were all above 100. It was found that height of subjects should be the best variable to estimate service time. Measured service time was inversely correlated with height of subjects. Service life time could be estimated by interpolation and extrapolation using inverse relationship between height and measured service time, for example, 28 minutes for male and female of 170 cm during resting, 10 minutes at the walk of 4 km/h and 5 minutes at the walk of 6 km/h considering safety margin of 20%. The study implies that program for estimating service time for the SCBA should require subject's height, speed of walk (4 km/h and 6 km/h) and fit testing. Considering safety margin, selecting younger subjects would be better. The study on the number of subjects and selecting facial dimensions should be more needed for the final program.

• 항공우주기술
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• 제8권2호
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• pp.105-112
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• 2009

위성발사체(KSLV)발사에 있어서 Telemetry data는 발사임무수행 및 비행안전통제를 위해서 매우 중요한 자료이다. 따라서 발사체의 전체 비행구간 동안에 Telemetry 신호를 안정적으로 수신하는 것은 매우 중요하며, 이를 위하여 우주센터에서는 고흥 센터, 제주추적소 및 해상의 다운레인지를 운용하고 있다. 본 문서에서는 발사임무설계에 따른 예상비행궤적 및 발사체 자세, 추적소 위치를 고려하여 각 추적소의 임무구간에 신호를 안정적으로 수신할 수 있는지를 판단하는 Link Margin 및 통신신뢰도를 분석한다. 보다 정확한 분석을 위해서는 예상비행궤적 및 추적소 위치를 고려하여 발사체기준의 추적소방향(Aspect angle 및 roll angle)에 대한 탑재송신부 유효방사전력(EIRP: Effective Isotropic Radiation Power) 특성을 사용하여야 하나, 본 분석에서는 가용자료의 한계로 95% spatial coverage 유효방사전력을 사용하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 A
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• pp.196-200
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• 1992

Transmission loss retains a complete set of system state information. If we could exploit its behavior, we could find various useful applications. This study is a such exploitation to find same possibilities of the loss application. It seems to have very prospective possibilities. It has been tried to establish some network indices to indicate operation margin. And further some prospective applications are suggested.

• Nuclear Engineering and Technology
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• 제31권6호
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• pp.66-82
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• 1999

The national long-term R&D program, updated in 1997, requires Korea Atomic Energy Research Institute(KAERI) to complete by the year 2006 the basic design of Korea Advanced Liquid Metal Reactor(KALIMER), along with supporting R&D work, with the capability of resolving the issue of spent fuel storage as well as with significantly enhanced safety. KALIMER is a 150 MWe pool-type sodium cooled prototype reactor that uses metallic fuel. The conceptual design is currently under way to establish a self-consistent design meeting a set of major safety design requirements for accident prevention. Some of the current emphasis includes those for inherent and passive means of negative reactivity insertion and decay heat removal, high shutdown reliability, prevention of and protection from sodium chemical reaction, and high seismic margin, among others. All of these requirements affect the reactor design significantly and involve extensive supporting R&D programs. This paper summarizes some of the results of conceptual engineering and design analyses performed for the safety of HAMMER in the area of inherent safety, passive decay heat removal, sodium water reaction, and seismic isolation.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2009년도 춘계학술대회
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• pp.489-499
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• 2009

Through the process of HALT (Highly Accelerated Life Test) between 2003 to 2008, we are about to research on the design method for minimum test for all error modes that are classified and analyzed to obtain more margin able product.

• 풍력에너지저널
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• 제14권3호
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• pp.109-119
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• 2023

A structural safety evaluation was conducted for the stabbing system for the pre-piling jacket substructure currently being developed in South Korea, considering pile construction errors due to its lateral movement that may occur during construction in the ocean. Based on (1) the maximum stress generated by the stabbing system, (2) the maximum rotational displacement of the guide cone, and (3) the maximum stress generated by the horizontal hydraulic pressure cylinder, the structural safety of the stabbing system was examined under the initial loading condition and three possible load combinations during its construction. In order to evaluate the structural safety of the stabbing system, a concept of stress safety factor (= Yield stress / Max. Von-Mises stress) was used. It was found that the stabbing system considered in this study has a sufficient margin of safety.

• International Journal of Railway
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• 제5권2호
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• pp.84-88
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• 2012

Derailment due to wheel failure would cause a tremendous social and economical cost in service operation. It is necessary to evaluate quantitatively the safety with respect to high-speed train. Although the safety of railway wheel has been ensured by an regular inspection, all critical defects cannot be detected in inspection cycles and the wheel has been replaced because a defect quickly become critical for safety. Therefore, it is important to calculate quantitatively the fracture limit and remnant life of damaged railway wheel in wheel-rail system. In present paper, the critical crack size of wheel for high-speed train is simulated based on fracture scenario and the safety of wheel is evaluated.

• 수산해양기술연구
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• 제33권1호
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• pp.76-83
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• 1997

To investigate a safety margin in the design of structural plant, plastic collaspse behaviors of statically indeterminate beams were numerically as the preliminary study. Through the calculations, it was revealed that the ultimate strength of statically indeterminate beams is much higher than that of statically determinate beams.

• 한국해양공학회지
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• 제3권2호
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• pp.645-645
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• 1989

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.913-914
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• 2011