• 비파괴검사학회지
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• 제33권6호
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• pp.519-523
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• 2013

A steam generator (SG) tube is an important component of a nuclear power plant (NPP). It works as a pressure boundary between the primary and secondary systems. The integrity of a SG tube can be assessed by an eddy current test every outage. The eddy current technique(adopting a bobbin probe) is currently the main technique used to assess the integrity of the tubing of a steam generator. An eddy current signal analyst for steam generator tubes continuously analyzes data over a given period of time. However, there are possibilities that the analyst conducting the test may get tired and cause mistakes, such as: missing indications or not being able to separate a true defect signal from one that is more complicated. This error could lead to confusion and an improper interpretation of the signal analysis. In order to avoid these possibilities, many countries of opted for automated analyses. Axial ODSCC (outside diameter stress corrosion cracking) defects on the tubes of OPR1000 steam generators have been found on the tube that are in contract with tube support plates. In this study, automated analysis software called CDS (computer data screening) made by Zetec was used. This paper will discuss the results of introducing an automated analysis system for an axial ODSCC on the tubes of an OPR1000 steam generator.

• 융복합기술연구소 논문집
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• 제2권2호
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• pp.13-19
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• 2012

This Design research is a design of rescue equipment combined with beach garbage can for prompt rescue at the time of the accident in water. As a usual, it is used as garbage can hanging a garbage bag on the holders located in both sides, and it can be used to rescue drowning men promptly taking out a rescue tube located inside of the equipment at the time of the accident in water. Support is consisted of beach one, wall-hanging one and pipe one, and it could be installed to match the situation because it can be combined with all main frames. As a usual, it is used as garbage can in seaside, but it can be used to rescue drowning men promptly taking out a rescue tube after pulling the handle located in front of main frame at the time of the accident in water, and it can be used to pull drowning men out of the water because rope is kept in rescue tube.

• Advances in concrete construction
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• 제6권5호
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• pp.485-507
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• 2018

Concrete-Filled Steel Tube (CFST) columns are an increasingly popular means to support great compressive loads in buildings. The residual strength capacity of CFST stub columns may be utilized to assess the potential damage caused by fire and calculate the structural fire protection for least post-fire repair. Ten specimens under room conditions and 10 specimens under fire exposure to the Eurocode smouldering slow-growth fire were tested to examine the effects of diameter to thickness D/t ratio and reinforcing bars on residual strength capacity, ductility and stiffness of CFST stub columns. On the other hand, in sixteen among the twenty specimens, three or six reinforcing bars were welded inside the steel tube. The longitudinal strains in the steel tube and load-displacement relationships were recorded throughout the subsequent compressive tests. Corresponding values of residual strength capacity calculated using AISC 360-10 and EC4 standards are presented for comparison purposes with the experimental results of this study. The test results showed that after exposure to $750^{\circ}C$, the residual strength capacity increased for all specimens, while the ductility and stiffness were slightly decreased. The comparison results showed that the predicted residual strength using EC4 were close to those obtained experimentally in this research.

• 대한소화기학회지
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• 제72권6호
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• pp.308-312
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• 2018

Percutaneous endoscopic gastrostomy (PEG) is widely used to provide nutritional support for patients with dysphagia and/or disturbed consciousness preventing oral ingestion, and PEG tube placement is a relatively safe and convenient non-surgical procedure performed under local anesthesia. However, the prevention of PEG-insertion-related complications is important. A 64-year-old man with recurrent pneumonia underwent tracheostomy and nasogastric tube placement for nutritional support and opted for PEG tube insertion for long-term nutrition. However, during the insertion procedure, needle puncture had to be attempted twice before successful PEG tube placement was achieved, and a day after the procedure his hemoglobin had fallen and he developed hypotension. Abdominal computed tomography revealed injury to a pancreatic branch of the superior mesenteric artery (SMA) associated with bleeding, hemoperitoneum, and pancreatitis. Transarterial embolization was performed using a microcatheter to treat hemorrhage from the injured branch of the SMA, and the acute pancreatitis was treated using antibiotics and supportive care. The patient was discharged after an uneventful recovery. Clinicians should be mindful of possible pancreatic injury and bleeding after PEG tube insertion. Possible complications, such as visceral injuries or bleeding, should be considered in patients requiring multiple puncture attempts during a PEG procedure.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.50-52
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• 2005

In this paper, the analysis of the eddy current testing(ECT) signals under thc Influence of the ferromagnetic support plate was performed in steam generator(SG) tube of nuclear power plant. In order to remove the influence of the ferromagnetic support plate, a multi-frequency ECT was used. The models which was established for the analysis of the signals is calculated using numerical analysis of finite element method. Through the result of numerical analysis, improved signals is acquired considering the influence of the ferromagnetic support plate using mixing of multi-frequency This paper is presented the residual errors and the phase changes for analysis of the defect signals which should be considered when conducting a ECT using multi-frequency.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2008년도 추계학술발표대회 및 제15회 신소재 심포지엄
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• pp.35.2-35.2
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• 2008

• 한국콘텐츠학회논문지
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• 제21권3호
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• pp.752-760
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• 2021

본 연구는 정보통신기술의 발달로 직업으로서의 선호도가 높아지고 있는 유튜브 크리에이터 종사 의향의 예측 요인을 검증하는 데 목적을 두었다. 이를 확인하기 위해 Z세대(20세~24세)의 직업 가치관, 관심과 인식, 자아존중감, 종사 의향 등을 조사하였다. 다중 회귀분석을 실시한 결과, 실재형(-), 예술형(+), 기업형(+)의 직업 가치관이 유의한 영향력을 보였고, 유튜브에 관한 관심도 역시 정적으로 유의한 영향을 미쳤다. 즉, 실재형의 직업적 성격을 가진 사람들일수록 유튜브 크리에이터 종사 의향이 낮은 것으로 나타났으며, 예술형, 기업형 점수가 높은 사람들은 유튜브 크리에이터로 종사할 의향이 높은 것으로 나타났다. 더불어 유튜브에 대한 관심이 높을수록 종사 의향이 높은 것으로 나타났는데, 본 연구는 이러한 결과를 기반으로 직업으로서 유튜브 크리에이터에 대한 진로 지원 서비스 구축의 필요성, 직업 가치관이나 개인의 성향에 따른 차별화된 접근의 필요성 등의 시사점들을 논의하였다. 본 연구는 최근 증가하고 있는 유튜브 크리에이터에 대한 관심도를 반영하여 직업적 관점에서 유튜브 크리에이터에 대한 종사 의향, 그리고 영향요인을 확인하였다는 점에서 의의를 갖는다.

• Journal of Advanced Marine Engineering and Technology
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• 제31권4호
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• pp.363-369
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• 2007

Probably the most significant heat transfer in the cryogenic liquid hydrogen storage tank from the atmosphere may occur through its support system. In this paper the efficient support system for the cryogenic storage vessel was newly developed and analysed. The support system was composed of a spherical ball as a supporter to reduce the contact area. which is located between two supporting SUS tubes inserted SUS and PTFE blocks. Numerical analyses for temperature distribution, and the thermal stress and strain of the support system were performed by the commercial codes FLUENT and ANSYS. The heat transfer rate of the supporter was evaluated by the thermal boundary potential method which can consider the variation of thermal conductivity with temperature. The results showed that the heat transfer rate through the developed supporter compared with the common SUS tube supporter was significantly reduced. The thermal stress and strain were obtained well below the limited values. It was found that the developed supporter can be one of the most efficient support systems for cryogenic liquid storage vessel.

• 해양환경안전학회지
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• 제24권6호
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• pp.803-809
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• 2018

갭색법(gap & sag method)은 선박 건조과정에서 축을 조립하기 전 최종적으로 축이 축계정렬 설계치와 동일한 위치에 거치되었는지의 여부를 확인하기 위해 사용되고 있는 방법이며, 조립 전 프로펠러축을 기준축으로 하여 양 축의 플랜지에서 축 자중에 의해 발생하는 갭색값을 통해 나머지 축계의 위치를 순차적으로 확정해 나간다. 만일 설계치와 다르게 기준축이 거치되는 경우 연쇄적으로 나머지 축의 거치에 영향을 주게 된다. 또한, 축 조립 후 검증과정에서 측정된 베어링 반력이 설령 설계치를 만족하더라도 선미관 후부측에서의 프로펠러축과 베어링간 상대적경사각을 추정할 수 없게 됨으로써 결과적으로 축계의 안정성에 부정적인 영향을 미칠 수 있다. 이러한 문제를 해결하기 위하여 본 연구에서는 실제 선미관 베어링 발열 및 개방검사 사례를 통해 선미관 베어링 유효지지점에 관한 이론계산 및 실측치분석 연구를 수행하고 이를 바탕으로 축계 정렬오차를 최소화하기 위한 축계 시공방법을 제안하였다.

• KSTLE International Journal
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• 제3권1호
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• pp.68-73
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• 2002

A fretting wear experiment in roam temperature air was performed to evaluate the wear mechanism of fuel rod using a fretting wear tester, which has been developed for experimental study, The main focus was to compare the wear behaviors of fuel rod against support springs with different contact contours (i.e. concave and convex). Wear volume, degree or surface hardening and adhesion tendency of wear particle were examined by the surface roughness tester. The result indicated that with a change of contact condition from contact force of 5 N to 0.1 mm gap, the wear volume of tube increased in the condition of concave spring, but slowly decreased in convex spring. From the results of SEM observation, wear mechanism of each test condition was also dependent on the spring shapes. The wear mechanism of each test condition in room temperature air is discussed.