• Journal of the Society of Disaster Information
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• v.18 no.4
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• pp.746-753
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• 2022

Purpose: The purpose of this study is to review the safety of small tunnels for food storage excavation in the 1960s~1970s and to improve the stability of small tunnels. Method: A visual inspection and a hammer test were used to conduct safety tests, and the visual inspection is one of the tests conducted for non-destructive testing, and the hammer test is one of the types of hitting methods of rebound hardness. Result: According to the integrated analysis of the survey area data, there are generally good appearance, but there are many small cracks and complex geological conditions, requiring continuous observation and attention. Seven of the 23 tunnels require safety diagnosis, one collapse, one safe, and 14 require continuous observation and attention. Conclusion: All parts of small tunnels should be checked and recorded from time to time, and stability is expected to be improved when reinforcing small tunnels proposed in this study.

• Tunnel and Underground Space
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• v.9 no.4
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• pp.337-349
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• 1999

There are many difficulties to the engineers in the assessment of tunnel safety. Consequently, objective assessment of concrete lining is hard even by the experts of tunnel assessment. Of several difficulties in the assessment of tunnel safety, in this study, tunnel concrete lining was focussed iud evaluated quantitatively and objectively using the Fuzzy theory which it generally considered to be appropriate for the assessment, control and judgment. T-FLAS based on fuzzy theory was developed in this study for the quantitative and objective assessment of the concrete lining in tunnels. Based on the application of T-FLAS on the evaluated field data, it was shown that the assessment system using fuzzy theory(T-FLAS) can be the effective and objective method for the assessment of concrete lining.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1998.05a
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• pp.339-345
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• 1998

원자력발전소는 발전소의 안전성 확보를 위해 대기중인 계통의기기(component)들을 가동중에 주기적으로 시험하고 있다. 시험 대상은 주로 미국 기계학회(The American Society of Mechanical Engineers: ASME)에서 정해진 안전등급 1.2,3급의 밸브나 펌프 등으로서, 원자력 발전소를 안전하게 정지시키거나 정지상태를 유지시기는 또는 사고를 완화시키는 기능과 관련돼 있는 기기들이다. 국.내외 원자력 발전소의 안전성 관련 기기들에 대해 수행되는 가동중시험(In-Service Test: IST)의 요건 및 주기 등은 대부분 ASME코드 규정을 근거로 하고있다. (중략)

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.70-70
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• 2004

국내 도시철도차량의 운행이 지속되면서 차량 사고가 발생함에 따라 차량복구의 안전성 확보와 복구보수비용 절감 등에 기여할 수 있는 안전진단 수행체계의 법제화를 통한 도시철도차량의 안전운행 확보가 절실하다. 그러므로 도시철도차량 안전진단은 차량을 복구하기 전 복구 가능여부를 확인하기 위하여 상태평가, 안전성평가 등을 실시하는 것이다.(중략)

• The Korean Journal of Food And Nutrition
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• v.24 no.4
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• pp.777-785
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• 2011

For the purpose of develop semi-solid baby food, we investigated ingredients, processing aids as a thickener, processing suitability test, natural antibrowning agent, packing method, novel preservation technology, storage test and quality evaluation. In results, semi-solid baby food was developed. It's formulation is eco-friendly apple as a main ingredients, natural rhubarb extract 5% and thickener 4%. Thickener was used brown rice puffing powder and sweet pumpkin puffing powder. High pressure processing(HPP) and pouch packaging was used as processing and novel preservation technology. In results of storage test and quality evaluation, shelf-life of semi-solid baby food was 15 days in $5^{\circ}C$ cold storage and hedonic score of sensory evaluation was 4.3/5.0. Taste of them was fresh and sweet.

• Journal of the Korean Geotechnical Society
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• v.28 no.9
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• pp.31-45
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• 2012

This study was conducted to estimate the stability of a quay wall in case of wave overtopping under the combined action of an earthquake and tsunami using limit equilibrium method. The tsunami force was calculated by using a numerical program called TWOPM-3D (3-D one-field Model for immiscible TWO-Phase flows). Especially, the wave force acting behind the quay wall after a tsunami wave overtopping was estimated by treating back fill as a permeable material. The stability of the quay wall was assessed for both the sliding and overturning modes under passive and active conditions. The variation in the stability of the quay wall with time was determined by parametric studies, including those for the tsunami wave height, seismic acceleration coefficient, internal friction angle of the soil, wall friction angle, and pore water pressure ratio. When the earthquake and tsunami were considered simultaneously, the tsunami induced wave overtopping increased the stability of the quay wall under the passive condition, but in the active condition, the safety factors decreased.

• Journal of Korean Society of Transportation
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• v.28 no.1
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• pp.157-163
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• 2010

It is well known that weather conditions are closely related with the number and severity of traffic accidents. At present, installation of safety countermeasures including systems is common approach to reduce the damage of traffic accidents at expressways. In this study, the differences of causation factors to influence traffic accidents considering road alignment characteristics and weather conditions. In order to identify the relationship between road and weather conditions, discriminant analysis has been performed with 500 traffic accident data at expressways. Weather conditions are divided into several categories such as snow, sunny, rain, fog, and cloud. Also, road conditions such as types of pavements, grades are analyzed. As the results, major impacting road conditions to traffic accidents are concrete pavement and 3% or more down grades. In these road conditions, visible distance will be reduced and actual braking distances will be increased. This study shows that the expressway sections under concrete pavement and down grades should be more cautious than other sections. It also shows that fog condition is the mose dangerous situation in terms of traffic accidents.

• Proceedings of the Korea Contents Association Conference
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• 2016.05a
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• pp.195-196
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• 2016

본 연구는 건설된 구조물의 주요 구조부재에 각종 계측 Sensor를 설치하여 이로부터 다양한 정보를 제공받아 Monitoring하는 계측 System은 대형구조물의 구조적 응답을 계측하여 분석하고, 구조물의 위험요소를 사전에 발견하고 분석하여 적절한 대책을 수립함으로써 대형 시설물의 수명연장 및 유지관리 비용의 효율성을 높이고, 구조물의 사용성 및 안전성을 확보하고, 그 설계수명을 유지할 수 있는 것이다. 계측전 초기치와의 비교 및 시간 경과에 따른 추이 분석을 통해 이상상태를 발견하는 신호 기반 감시 수행하고 있고, 상태판정 및 손상도 추정이 가능하므로 향후 계속해서 발전시켜 나갈 수 있는 지식기반 감시시스템이 필요하므로 본 연구에서는 공간 정보기반의 정보를 재생하여 GNSS/USN기술을 접목시켜감으로 대형시설물 안전관리가 매우 용이하게 적용할 수 있도록 하였다.

• Journal of Advanced Navigation Technology
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• v.22 no.3
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• pp.179-188
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• 2018

In developing avionics systems, safety analysis and evaluation specified in SAE ARP4761 (Methods and Guidelines for Civil Aviation System and Equipment Safety Assessment Process) are carried out to prevent air accidents. Safety analysis requires knowledge of the abnormal state of the system, not its normal state, and its interrelationships with other standards. Therefore, a tool that automatically outputs data which proves compliance with safety certification standards is required. In this study,In this study, Schematized the safety analysis procedure of the specification and studied the method of applying the safety analysis CAD tools to individual procedure. As an example study, ARP4761 analysis was performed on the wheel brake system (WBS) of the ARP4761 appendix.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.04a
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• pp.745-745
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• 2012

원자력발전소에서 비상디젤발전기는 노심의 안전성을 지키는 매우 중요한 역할을 담당하고 있다. 이를 위해 디젤발전기는 신뢰성능 높게 유지하도록 규제요건이 마련되어 있다. 디젤발전기의 엔진 상태를 주기적으로 감시하고 평가하기 위해서는 엔진 상태 신호 분석 기술이 필요하다. 엔진 상태 신호 분석에는 연소분석과 진동 및 초음파 측정 및 분석기술이 중요한 비중을 차지한다. 연소 분석은 디젤 엔진의 개별 실린더에 대한 연소 성능에 대한 정보를 제공한다. 진동 및 초음파 분석은 이벤트 타이밍과 기계적 상태에 대한 정보를 알려준다. 이들 신호는 정상적인 부하로 운전하는 디젤엔진의 가동에 영향을 미치지 않고 수집할 수 있다. 엔진 상태 신호 분석을 이용하는 주요 동기는 전통적으로 장비 제작자의 권고에 따라 수행되는 분해-검사 유지 보수 프로그램을 일부 대체하고 예측정비를 통해 신뢰도를 유지하기 위함이다. 상태 진단정비는 엔진 상태 신호분석을 주로 이용하여 엔진의 신뢰도와 이용률을 증가시킬 수 있다. 본 논문에서는 국내외서 경험한 엔진상태신호 측정 및 분석 사례를 기술하였다.