• Journal of the Society of Disaster Information
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• v.18 no.2
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• pp.252-260
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• 2022

Purpose: As the intensity and frequency of natural hazards are increasing due to climate change, external events that affecting nuclear power plants(NPPs) may increase. NPPs must be protected from external events such as natural hazards and human-induced hazards. External events that may occur in NPPs should be identified, and external events that may affect NPPs should be identified. This study introduces the methodology of identification and screening methods for external events by literature review. Method: The literature survey was conducted on the identification and screening methods of external events for probabilistic safety assessment of NPPs. In addition, the regulations on the identification and screening of external events were investigated. Result: In order to minimize the cost of external event impact analysis of nuclear power plants, research on identifying and screening external events is being conducted. In general, in the identification process, all events that can occur at the NPPs are identified. In the screening process, external events are selected based on qualitative and quantitative criteria in most studies. Conclusions: The process of identifying and screening external events affecting NPPs is becoming important. This paper, summarize on how to identify and screen external events for a probabilistic safety assessment of NPPs. It is judged that research on bounding analysis and conservative analysis methods performed in the quantitative screening process of external events is necessary.

• Journal of Environmental Impact Assessment
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• v.30 no.6
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• pp.393-412
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• 2021

This study examines the assessment systems of LEED v4.1, an eco-friendly building evaluation system in the United States, and SITE v2, an assessment system for sustainable outdoor spaces, and then compares and examines them from the perspective ofrelevant laws and institutional guidelines and standards in Korea. The conclusion is as follows. First, the US eco-friendly certification system basically not only establishes an independent evaluation system according to the field of expertise, but also provides a sustainable city and community through response to the climate crisis and the comfort of the external space environment. It can be evaluated that securing the quality of life of healthy and happy city dwellers is the top priority. Second, Korea's Green Building Certification System (G-LEED) was basically based on the American LEED system, but it was judged that there was a fundamental difference. It was judged that there is a limitation in not being able to achieve an integrated approach through the participation of various expert groups and stakeholders, but also in the accumulation of more scientific and reliable data and information through the application of cutting-edge information and communication equipment. Third, in the case of external space in Korea, a sustainable assessment system has not been established, and not only is it dispersed in various legal and institutional guidelines, but also its effectiveness is judged to be very low. Therefore, it is judged that it is urgent to introduce and secure the applicability of SITES v2, a sustainable outdoor space assessment system in the United States. It was judged that the effectiveness should be secured through the upward adjustment of the minimum Ecological Area Ratio.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.10a
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• pp.101-106
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• 2003

항공기 외부 장착물인 POD는 전자전 방해장치(ECM, electronic counter measures)로서 전자방해 장비 및 부분 부품인 전ㆍ후방 러그(lug)와 외부 케이스로 이루어져 있다. POD는 항공기 외부 동체 하단부 및 파일런(pylon)에 장착되어 작동하므로 항공기의 운용중 이륙부터 착륙간의 기동에 의한 피로하중을 주로 받게 되므로 POD 부품들에 대한 구조 건전성 확보하기 위해서는 MIL-STD-1530의 요구에 따라 내구성(durability) 및 손상허용설계(damage tolerance design) 의 평가가 요구되고 있다.(중략)

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.3
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• pp.56-64
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• 2016

While many assessment systems for buildings and indoor environment have been created with increasing interest in sustainable development, assessments for sustainable landscaping and outdoor environments have received less attention. Recently, the Sustainable Site Initiatives(SITES) was developed in the USA in order to evaluate and certify sustainable landscape design projects. The purposes of this study are to analyze sustainable landscape strategies and to review the certification system through case studies of SITES certified projects. Three certified projects in Texas were selected and literature review, site visits and interview were conducted. The results indicated that various sustainable and practical strategies were applied including soil preservation, use of native plants and recycled materials, and water harvesting. Also, SITES has benefits to encourage an integrated design process, community participation, and environmental education for the public. This suggests that a certification system for landscaping and outdoor environments needs to be developed to ensure sustainable site development, which helps extend the roles of the landscape architecture profession in sustainable design.

• Proceedings of KOSOMES biannual meeting
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• 2006.05a
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• pp.59-64
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• 2006

In this study, the risk of SRRs was assessed upon the scale of the damage of marine accidents. For the risk assessment, inner-outer dependence methods and special knowledge-based fuzzy logic were introduced. Also, in order to calculate the importance of assessment value in this study, a max min composition method was used for fuzzy logic based on the principle of fuzzy extension and the centroid of gravity method was used for non-fuzzy formation. In order to produce the importance of assessment items, the inner-outer dependence methods were used for assessment items, and markov analysis method was used for the importance of the final comprehensive assessment. As a result, the risk of SRR of Tongyoung and Yeosu was proven relatively higher, thus, it needs to have more rescue ships and rescue devices for relieving the risk in the future.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6A
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• pp.809-817
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• 2008

Recently, the external prestressing method is being much frequently used in strengthening reinforced concrete structures because of it's excellent load resistance and serviceability increases comparing to other strengthening methods. However, it is true that the research on fatigue performance of concrete structures strengthened by the external prestressing using FRP tendons is rare. Therefore, the purpose of this study is to evaluate the safety and feasibility of the external prestressing method by analyzing the characteristics of the reinforced concrete beam strengthening using FRP tendons under repeated loads. Test variables adopted in this experimental study are the types of external prestressing material (steel or FRP tendon) and the repeated load ranges. The repeated load range have the minimum 50% of yield load of reinforced concrete beam and the maximum 70-85%. The test beams are loaded by 4 point loadings with 3 Hz sine wave. From this experimental study, it is confirmed that the reinforced concrete beams strengthened using FRP tendons have sufficient safety against fatigue, especially in FRP tendon itself, tendon at deviators and tendon at anchorages.

• Proceedings of the Korean Society of Computer Information Conference
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• 2017.07a
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• pp.392-393
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• 2017

본 연구에서는 에너지 저장시스템인 ESS 에너지 분배에 관한 시스템을 설계 및 제작하고 성능을 평가하였다. ESS에 충전하는 방법은 현재 기존의 상용전원을 전지에 충전하는 방식과(연계형) 태양광 에너지를 이용한 방법(독립형)으로 나누어져 있다. 본 연구에서는 어느 한쪽을 선택해야하는 번거로움을 줄여 상용전원과 태양광을 동시에 충전할 수 있는 시스템으로 설계하였다. 이러한 방법은 날씨 및 기타 외부적 환경이 좋지 않을 경우 일반 상용전원(AC 220V)를 이용하며 외부적 환경이 좋을 때는 태양전지로 충전이 가능하도록 연계형과 독립형이 동시에 가능하도록 구성하였다. 또한 출력에서 기존의 AC 220V 출력뿐만 아니라 DC12V, 24V의 전압과 USB(5V)도 동시에 출력이 가능하게 설계하므로 필요한 전압을 외부의 인버터나 컨버터가 필요 없이 바로 사용할 수 있도록 배분하였다. 따라서 본 연구에서는 ESS의 전력을 효율적으로 배분하므로 효율성을 증가시키고 내부의 배터리를 보호하는 시스템을 구성하여 그 성능평가를 실시하였으며 실험결과 효율적으로 배분된 전력을 얻을 수 있음을 검증하였다.

• Korean Journal of Culture and Social Issue
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• v.21 no.3
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• pp.457-479
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• 2015

This study investigated the differential effects of subjective evaluation for attention and situation adaptability, and motivation on driving mobility as a function of driver's age. The results can be summarized as followings. First, subjective capability evaluation tended to decrease as the drivers' age increased, and lower evaluation for situation adaptability seemed to be recognized earlier than attentional ability in middle-aged drivers. Second, although subjective evaluation for attentional ability predicted positively driving mobility of all age groups, but only subjective evaluation for situation adaptability predicted positively driving mobility of older drivers. Third, among motivational elements, BAS predicted positively driving mobility of young and middle-aged driviers, whereas BIS predicted positively driving mobility of older drivers. Finally, middle-aged drivers tended show increased driving mobility when their attentional ability score and BAS were high, whereas older drivers showed lowest level of driving mobility when their situation adaptability score and BIS were low. These results suggest importance of integrated consideration for drivers' subjective evaluation for attention and situation adaptability, and motivation to understand characteristics of driving mobility in different age groups.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1440-1442
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• 2002

폴리머 애자는 여러 가지의 외부환경에 의하여 시간의 경과에 따라서 재료의 열화가 진행된다. 폴리머 애자를 평가하는 방법으로 기계적 특성, 전기적 특성, 환경적 특성 등의 평가방법이 있으나 각각의 특성평가에 있어서 국제, 국가 및 단체에 따라서 서로 다르다. 신뢰성 평가기준도 서로 달라 국내 실정에 맞는 폴리머 애자의 신뢰성 향상에 어려움이 있었다. 이러한 문제를 해결하기 위하여 폴리머 애자의 신뢰성 평가기준을 표준화할 필요성이 있다. 본 원고에서는 특고압 가공배전선로에 사용하는 폴리머 현수애자의 신뢰성 평가기준에 대하여 설명하였다. 장기신뢰성 평가를 위하여 다양한 외부환경을 모의하여 복합적인 스트레스를 가할 수 있는 복합가속열화설비에 대하여 설명하고 복합가속열화시험법을 결정하였다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.6
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• pp.68-75
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• 2021

In this study, the anchoring performance of 57mm headed bars anchored at the external beam-column joint under cyclic loading was evaluated. A total of 6 external beam-column joint test specimens were planned, and anchorage performance was evaluated by setting concrete compressive strength, side covering thickness, lateral reinforcement ratio, and fracture type as major experimental variables. As result of cyclic loading test, it was found that the factors that had the greatest influence on the anchoring capacity of the large-diameter headed bar anchored at the joint were the side cover thickness and the transverse reinforcing bar. It was confirmed that the 57mm large-diameter headed bar anchored at the external beam-column joint showed sufficient anchoring capacity even under cyclic loading.