• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.23-29
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• 2008

Most VE operation related to construction project is progressed in stage of planing or design phase, especially in case of domestic. It is encouraging fact and if you have VE process in stage of planning and design, you'll have experience a reduction of about 70% of total saving cost in which total construction process may occurred. However, recently the work of construction in overseas increase and almost is only construction-work, except planning and design process. As this reason, VE process for construction-work phase only is demanded in high necessity. VE in construction phase comes to accomplish intensively in the part which the design change does not follow, through know-how, equipment operating method and method of temporary-structure erection at the established construction-site learned, builders will be the possibility of reduction from 3% to 10% in constructive expense. This paper describes VE performing example in OO company's construction-work phase, and propose the methodology of VE performance in the phase of construction. And also it is aimed to extending VE applications into the overseas construction enterprise.

• 한국지반공학회논문집
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• 제38권1호
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• pp.35-45
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• 2022

개착공법으로 원형 수직구 건설 시, 가시설 흙막이 벽체는 일정 수준의 변위를 허용하는 연성벽체로 설계된다. 합리적이고 경제적인 연성벽체의 구조 설계를 위해서는 벽체에 작용하는 토압을 정확히 평가할 필요가 있다. 원형 수직구 벽체에 작용하는 토압은 주변 지반의 소성 변형과 밀접하게 연관되어 있으나, 이에 대한 연구는 부족한 상황이다. 본 연구는 원형 수직구의 단계 굴착을 원심모형시험을 통해 모사하고, 원심모형시험 중 촬영된 이미지에 이미지 해석 기법을 적용하여 원형 수직구 굴착 시 주변 지반에 발생하는 변형을 평가하였다.

• International Journal of Knowledge Content Development & Technology
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• 제12권4호
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• pp.41-65
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• 2022

This study would understand the overall perception of our society about public libraries, analyzing the texts related to public libraries, utilizing the semantic connection network & sentiment analysis. For this purpose, this study collected data from the last five years with keywords, 'Library' and 'Lifelong Learning Center' from January 1, 2016 through November 30, 2020 through the blogs and cafés of major domestic portal sites. With the collected data, text mining, centrality of keywords, network structure, structural equipotentiality, and sensitivity analyses were conducted. As a result of the analysis, First, 'reading' and 'book' were identified as representative keywords that form the social perception of public libraries. Second, it turned out that there were keywords related to the use of the library and the untact service due to the recent spread of COVID-19. Third, in seeking a plan for the development of public libraries through the keywords drawn to have positive meanings, it is necessary to create continuous services that can form a new image of the library, breaking away from the existing fixed role and image of the library and increase the convenience of use. Fourth, facilities and facilities for library services were recognized from a neutral point of view. Fifth, the spread of infectious diseases, social distancing, and temporary closure and closure of libraries are negatively related to public libraries, and awareness of librarians has been identified as negative keywords.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.79-80
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• 2022

In December 2017, a fire at the Jecheon Sports Center caused 29 deaths and 40 injuries, and about 2 billion won in property damage. It is a facility used by unspecified people as a publicly used establishment with a piloti structure. The damage was expanded due to the ignition of combustible exterior materials, Lack of fire protection in horizontal and vertical penetrations. Although legislation has improved since the fire, it is not retroactively applied, increasing the risk of fire in existing buildings. Accordingly, it is necessary to examine the case of the Jecheon Sports Center fire and draw out the problems. In this study, the fire simulation results and the Jecheon Sports Center fire are comparatively analyzed and used as basic data for fire reduction measures in publicly used establishment. As a result of the fire simulation drive, in the case of the second floor, the room temperature exceeded the human life safety standard of 60 ℃ after about 700 seconds had passed. In the case of three floor, it is predicted that the indoor temperature will exceed about 350 ℃. and temporary complexation will occur in the indoor combustibles.

• 한국표면공학회지
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• 제57권1호
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• pp.49-56
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• 2024

Superhydrophobic surfaces have been expected to be able to provide considerable performance improvements and introduce innovative functions across diverse industries. However, representative methods for fabricating superhydrophobic surfaces include etching the substrate or attaching nanosized particles, but they have been limited by problems such as applicability to only a few materials or low adhesion between particles and substrates, resulting in a short lifetime of superhydrophobic properties. In this work, we report a novel coating technique that can achieve superhydrophobicity by electrophoretic deposition of aluminum nitride (AlN) nanopowders and their self-bonding to form a surface structure without the use of binder resins through a hydrolysis reaction. Furthermore, by using a water-soluble adhesive as a temporary shield for the electrophoretic deposited AlN powders, hierarchical aluminum hydroxide structures can be strongly adhered to a variety of electrically conductive substrates. This binder-free technique for creating hierarchical structures that exhibit strong adhesion to a variety of substrates significantly expands the practical applicability of superhydrophobic surfaces.

• 정보처리학회논문지C
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• 제10C권2호
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• pp.163-170
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• 2003

본 논문에서는 에드-혹 네트워크에서 조합가중치 클러스터링 알고리즘을 적용하여 강건하고 신뢰성 있는 클러스터 기반의 그룹 멀티캐스트 방식을 제안한다. 에드-혹 네트워크는 고정된 통신 하부 구조의 도움 없이 이동 단말기로만 구성된 무선 네트워크이다. 제한된 대역폭과 높은 이동성으로 인하여 에드-혹 네트워크에서의 라우팅 프로토콜은 강건하고, 간단하면서 에너지 소비를 최소화하여야 한다. WCGM(Weighted Cluster Group Multicast)방식은 조합 가중치 다중 클러스터 기반 구조를 이용하고 기존의 FGMP(forwarding Group Multicast Protocol)방식의 장점인 제한적인 플러딩에 의한 데이터 전달방식은 유지하면서 클러스터 헤드 선출시 조합가중치를 적용한다. 이것은 안정적이며 강건한 데이터 전달 구조를 가지기 때문에 데이터 전달 구조를 유지하기 위한 오버헤드(Overhead)와 데이터 전달을 위한 오버헤드를 모두 줄이는 효과가 있었다.

• 한국전자통신학회논문지
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• 제9권7호
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• pp.767-772
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• 2014

임시망으로서 애드-혹 네트워크는 네트워크가 설치된 환경이나 구조에 의하여 많은 영향을 받는다. 본 논문에서는 센서 네트워크나 IoT(Internet of Things)와 같은 특수한 통신 환경에서 사용될 것으로 예상되는 격자구조 애드-혹 네트워크의 전송성능을 정보침해가 발생되는 측면에서 분석하고 대응 방안으로 모색하여 본다. 본 논문은 NS-2를 기반으로 한 컴퓨터 시뮬레이션을 사용하여 수행하였으며, 성능측정은 응용 서비스로 널리 사용되는 VoIP(Voice over Internet Protocol) 서비스를 대상으로 하였다. 성능 파라미터로는 MOS(Mean Opinion Score)와 호연결율을 사용하였다. 성능분석 결과 침해가 발생되는 애드-혹 네트워크에서 MOS의 경우 랜덤구조가 격자구조에 비하여 성능이 다소 높았고, 호연결율의 경우는 격자구조가 랜덤구조에 비하여 우수한 성능을 보였다.

• 한국강구조학회 논문집
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• 제27권4호
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• pp.371-376
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• 2015

현수교 주케이블 가설을 위한 임시 구조물인 캣워크의 비틀림 거동에 대해 연구를 수행하였다. 캣워크의 비틀림 변형은 작업원의 안전성과 작업성에 중요한 영향을 미친다. 이러한 이유로 설계단계에서는 크로스 브릿지의 간격을 조정하여 캣워크의 비틀림 변형이 일정 수준이하가 되도록 고려하고 있다. 이 연구에서는 캣워크의 비틀림 안전성과 관련된 크로스 브릿지의 설치 간격에 따른 영향을 분석하였다. 해석적 접근을 위해 크로스 브릿지를 포함한 상세 부분해석 모델을 작성하였다. 작성된 해석모델을 이용하여 크로스 브릿지 설치 간격에 따른 영향을 Prefabricated Parallel Wire Strand의 편심하중과 가설이 가능한 풍속 영역에서의 풍하중에 대해 검토를 수행하였다. 검토 결과 크로스 브릿지의 설치 간격이 캣워크의 비틀림 거동에 큰 영향을 줌을 확인하였으며, 검토 대상 교량의 캣워크는 비틀림 변형에 대해 안전성을 확보하고 있는 것으로 확인되었다.

• 한국건축시공학회지
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• 제6권1호
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• pp.87-91
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• 2006

Since water leakage and cracks are not the source of serious problems such as long-term lowering of performance and durability of a stricture, including damages to operating facilities of a structure, damages to internal finishing materials, exhibition, and goods, and pollution of residential environment, they might have led to development of positive coping skills; however, an instant loss of lives or property due to earthquake, explosion, typhoon, or a fire was indeed neglected. In these days, repair materials for leakage cannot help but being taken in temporary way without any noticeable countermeasure. This kind of repair is socially criticized many times that is defective construction even if this costs a lot. It was not arrange the standard for construction methods of sealer of injection type for leakage maintenance, even it has been used various type of construction methods for leakage part. In conclusion, we suggest that the construction methods of sealer of injection type for leakage maintenance for leakage to establish the leakage repairing technology as increase of structure demand. Therefore, it would be possible to provide a stage-by-stage solution by developing systematic research activities among the industry, schools, and research institutes to spread maintenance management techniques globally through technical solution to water leakage and cracks, acquisition of structural safety with prolonged durability for life cycle, reduction of water leakage repair expense s, and so on.

• Journal of the korean society of oceanography
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• 제33권1-2호
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• pp.35-40
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• 1998

In February and April 1997, three temporary interruptions of electric power production at the Uljin Nuclear Power Plant in the east coast of Korea were caused by the malfunction of the cool-ing-water supply unit. The clogging of the drum screens inside the unit caused by the surface swarm of the euphausiid Euphausia pacifica Hansen might be responsible for the malfunction. These incidents were of particular interest since such interruption of reactors' operation by krill swarms had not previously been reported. Using samples caught by the drum screens inside the cooling water-supply unit, we investigated the population structure of surface swarms. One occasion of nighttime and three occasions of daytime surface swarms were found in February and April 1997, respectively. The foreguts of more than 60% of E. pacifica in nighttime surface swarm were in full condition. This evidence suggests that E. pacifica aggregates to the surface water at night for feeding. In daytime surface swarms consisting of mature E. pacifica, however, foreguts in full condition were only found in less than 10eio of krill examined, suggesting that daytime surface swarms are closely related to breeding activity. During the study period, the growth rate of mature females was more than twice higher than that of mature males. Analyses of the sex-ratio and length-frequency data show a decrease in the portion of males with increasing size. There was a decline in the number of males of 19 mm in length. Energy loss during spermatophore transfer may result in the death of male E. pacifica, as found in male E. superba.