• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.87.1-87.1
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• 2015

우리나라는 세계적으로 보기 드문 조류발전의 적지이며, 특히 진도 울돌목, 장죽수도, 맹골수도, 완도 횡간수도 등 서남해안에 조류에너지 여건이 좋은 상태이다. 조류발전시스템은 물속에 잠겨서 동작하는 형태이므로, 대형 고정 설비가 요구되어 높은 부대비용 발생과 이상유무 발생시 유지보수가 어려운 문제가 있다. 이를 위해 설비 및 설치비용을 줄이는 부유식 형태와 유지보수가 용이한 구조 설계를 적용한 실용적인 조류발전시스템 개발하며, 주요 적용처로 관심이 높아져 가는 에너지자립섬 적용을 목표로 섬내 전기 수요에 부합되는 15 kW급 조류발전을 공급하고자 하며, 이외 다양한 해양에너지를 활용한 에너지 자립화 방향을 제시하고자 한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.06a
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• pp.516-518
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• 2012

해상에서 선박의 충돌확률을 평가하는 것은 해당해역의 잠재적인 해상교통 위험성을 평가하는데 있어 중요하다. 서남해권 해상교통에 중요한 요충지인 완도해역은 동서방향으로는 횡간수도 통과선박들이 항해를 하며, 남북방향으로는 완도항 입출항 선박과 다도해 섬들을 입출항하는 여객선들이 통항을 이루고 있다. IALA 정량적인 해상안전 평가방법인 IWRAP은 통항량, 선속, 길이, 선박의 통항분포로부터 해상에서 통항의 위험도를 평가하므로 인적, 지리적, 환경적 등 주관적인 요소들이 많은 정성적인 평가방법에 비해 적용이 간단하다. 본 연구에서는 VTS 섹터 관제의 관점에서 항로구간별 해상교통의 특징과 개선책을 세우기 위해 IWRAP을 활용하여 완도 해역의 충돌확률을 산출하고자 한다.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.608-609
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• 2011

In this study, we tried to validate FLUENT solver model and domain setting for the problem of convective heat transfer in multiple tube bank under transitional zone. We have paid special attention to verify proper boundary conditions and the grid convergence. Through validation work, it is found that unsteady solution method with two-dimensional simulation domain can produce reasonable accurate results compared with existing experimental data. Simulation results with steady solution generates relatively large error. We found that both steady and unsteady method for three-dimensional domain shows acceptable accuracy. Further parametric study for deriving correlation from transverse and longitudinal pitch is currently underway.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.10a
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• pp.157-159
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• 2012

해상 교통량 증가에 따른 연안해역 해상교통밀집도가 증가되고 있다. 그러므로 해상교통안전관리를 위해 실 해역의 해상교통패턴을 파악하여 해상교통지수를 평가하는 것이 중요하다. 분석대상해역의 실제 선박위치, 속력, 침로를 고려한 CPA-TCPA분석은 통계적인 선박데이터에 의한 분석보다 해당해역의 실제적인 VTS영향 등 교통환경을 반영한다. 본 연구에서는 횡간수도와 완도진입수로의 항로가동률을 분석하고, 해당 해역에서 교차되는 선박들의 CPA, TCPA 등을 분석하여 해상교통안전지수를 평가하고자 한다. 또한 산출된 해상교통안전지수를 해당 해역의 통계적인 해상교통안전지수와 비교 및 분석하고자 한다.

• Journal of computational fluids engineering
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• v.17 no.3
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• pp.39-44
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• 2012

In this study, a longitudinal pitch effect on in-line tube bank heat transfer has been analyzed numerically. To verify the accuracy of the solver model and boundary conditions, global Nusselt number(Nu) and pressure drop across the 2 row tube bank are compared with the existing experimental correlations under 500 ~ 2,000 Reynolds number(Re) range. By changing transverse pitch($S_T$) or longitudinal pitch($S_L$) separately in tube bank, we're trying to identify the each effect on heat transfer. We found that the effect of transverse pitch can be accounted for Reynolds number evaluated with maximum velocity($V_{max}$) at the smallest flow area similar to most existing correlations. Variation of the longitudinal pitch($S_L$) has a greater impact on the heat transfer compared to the transverse pitch($S_T$). Overall Nusselt number increases with larger longitudinal pitch($S_L$), however individual Nusselt number of the tube row has significant difference after the first row.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.12
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• pp.1815-1819
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• 2009

Based on the soft and rigid extents, tissues are mainly divided into two groups in mammals, soft tissues including heart, lung, kidney and brain, and hard tissues including tendon, cartilage, teeth and bone. Among various tissues, bone, a dynamic rigid organ, is continuously remodeled by the opposing functional activity between bone formation by osteoblasts and bone destruction by osteoclasts. Bone protects the soft tissues and provides mineral reservoirs, which can supply the mineral needs of other soft tissues to normally maintain cellular function. While calcification in bone is an important action to fundamentally support the body and protect the soft tissues, calcification in soft tissues, including the heart, aorta, kidney, lung and spleen, results in severe organ damages, eventually causing sudden death. A growing body of evidence indicates that the osteoporotic patient who are aging, post-menopausal, diabetes and chronic kidney disease simultaneously represent a high clinical incidence of soft tissue calcification, illustrating a link between soft tissue calcification and bone decalcification (osteoporosis). This study will review what is currently known about the connection between bone decalcification and soft tissue calcification.

• Journal of Practical Engineering Education
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• v.14 no.3
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• pp.593-600
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• 2022

Various sensors such as lidar, radar, and camera are fused and used in autonomous vehicles. Rider and radar sensors are difficult to popularize because they are expensive equipment. In order to popularize autonomous vehicles, research that can replace expensive equipment is continuously being conducted. In this paper, we use a single camera that is inexpensive and can be easily mounted. We propose a method for detecting the wheels and adjacent lanes of a front-side vehicle of a driving vehicle and estimating distances. Our proposed method detects lanes and wheels from frame images after frame extraction via input images. In addition, the distance is measured and compared with the actual distance measured in the actual road environment. The distance could be calculated relatively accurately within the error range of ± 3 cm. Through this, it is expected that the camera can be used as an alternative means when the cost of autonomous vehicles is reduced or when the lidar or radar sensor fails.