• Journal of the Korean Society of Marine Environment & Safety
• /
• v.1 no.1
• /
• pp.9-25
• /
• 1995

Although the studies carried out in recent years have provied much new information about channel widths and alignment, they are not consistent in their results. In addition, as a result of variations in local condition and type of traffic accommodated, the dimensions of the channel widths vary over a wide range. Therefore, the recommendation made by the maritime engineering organizations over the world, do not offer detailed and decisive optimal design criteria and are all different. It, therefore, was attempted in this paper to draw a decisive guideline on the optimal widths and alignment of the navigational channels, which can be utilized by the port designers at the stage of the planning. The guideline was drawn through the comparison and analysis of the existing guidelines of the U.S.A, Japan and PIANC and simulation experiment. The simulation experiment was carried out using the "Off Line Port and Waterway Design Simulator" to find the optimal dimensions of the widths of the navigational channels. 90 different simulation runs were conducted at the 3 different secenario channels. New guidelines, the result of the study, is expected to be used usefully by the Korean port designers when designing the rapodly developing ports in Korea. in Korea.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2018.05a
• /
• pp.65-66
• /
• 2018

국내 항만의 건설 및 확장 보수를 위한 설계 단계에서의 평면배치 검토시 항내측으로 내습하는 파랑변형특성에 대한 정밀한 평가는 필수적이다. 이에 따라 많은 수학적 모델들이 연안역과 항만에서의 파랑전파와 변형에 대해 개발되어 왔다. 특히 항내정온도의 해석은 항만 사용성 측면에서 매우 중요하며 실제 해상의 파랑상태와 유사한 불규칙파로의 해석이 요구되어 지고 있다. 항내정온도 해석에 있어서 항내파랑장 형성에 크게 영향을 미치는 구조물의 반사율을 효과적으로 적용하는 것은 매우 중요하다. 하지만, 구조물의 반사율은 이론계산이 어렵고, 일반적으로는 모형실험 혹은 현지관측에 의해 추정된다. 따라서, 일반적인 경우 비용 및 시간상의 제약으로 인해 평면 파랑모형으로 정온도 해석시 반사율의 적용은 구조형식별로 연구자들에 의해 개략 제시된 반사율을 적용하고 있다. 특히, 다방향 불규칙파의 적용시에 경계조건으로는 다방향 불규칙파를 효과적으로 제어할 수 있는 부분반사 경계면과 계산영역 밖으로 나가는 파랑에 대해서 인공적인 흡수층 또는 감쇠층(artificial damping layer)을 설정하여 반사를 제어하는 기법을 많이 적용하고 있다. 이때 항만구조물의 부분반사는 파랑제원에 따른 damping layer의 parameter의 조정에 의해 구조물의 구조형식별 반사율을 적절히 재현할 필요성이 있다. 본 연구에서는 불규칙파를 대상으로 damping layer의 parameter(무차원 감쇠계수, 감쇠층의 두께)등의 변화에 따른 반사율의 변화특성을 고찰하고, 향후 부분반사 경계면으로 damping layer가 적용되는 평면 파랑모형의 정온도 해석시 부분반사의 적용에 대한 기초자료를 제공하고자 한다.

• Journal of the Korean Applied Science and Technology
• /
• v.29 no.2
• /
• pp.175-183
• /
• 2012

This study was evaluated the antiatopic activity of cream containing a herb extracts mixed with Houttuynia cordata in DNCB-induced BALB/c atopy mouse. The randomized complete block design was done by BALB/c mouse into two groups, of which the control group with atopy and the cream treatment group. It was found that each level of IgE and histamine in blood was significantly decreased in the cream treatment group, compared with the DNCB-induced atopy control group. When the cream was applied to the atopy mouse, it could be observed that its skin recovered to normal condition with the skin surface being clean and smooth without any horny tissue. The results suggest that the application of herb extracts mixed with Houttuynia cordata has an antiatopic activity through a inhibition of histamin emissions with reducing the levels of blood IgE in BALB/C atopy mouse.

• Journal of Korea Port Economic Association
• /
• v.25 no.2
• /
• pp.201-230
• /
• 2009

There are few studies on the human resource development and management of container terminal in Korea. In this situation, we try to analyze the training and education of Busan port container terminals. This study took a close look at present condition of training and education of container terminals in Busan and compared it with foreign advanced port. And conducted a questionnaire survey on the actural condition and system of it. Based on the survey result, we examine the problems and suggest an alternative plan to improve the training and edcation of Busna Port container terminals.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.28 no.1
• /
• pp.72-82
• /
• 2022

The anchorage among harbour facilities should ensure sufficient water surface area for safe anchoring. A general method is to consider the L.O.A of the target ship and the depth and bottom quality of anchorage to calculate the water surface area of anchorage. However, the gross tonnage is used as a unit of the ship capacity standard of anchorage based on the detailed rules for harbour facilities operation in Korea. In this study, the gross tonnage is converted to L.O.A to calculate the actual anchoring radius of the target ship. This actual anchoring radius exceeds at 25 anchorages (among 90 anchorages) compared with the designated water surface area. Therefore, as an improvement plan of the ship capacity standard for anchorage, L.O.A should be used as a unit for anchorage based on the detailed rules for harbour facilities operation and related Korean maritime laws.

• Korean Journal of Heritage: History & Science
• /
• v.55 no.1
• /
• pp.5-34
• /
• 2022

The purpose of this study is to investigate the unique contrasting landscape characteristics of imperial tombs of Qing dynasty by examining the characteristics of facility layout in which location, Feng shui, and siblings are harmonized with the 12 Qing Dynasty Hwanggyeongchim. Through literature surveys, field observation and interviews, videos and drawing comparison, and inductive contrast analysis, the contrasting landscape characteristics of imperial tombs in the Qing Dynasty were analyzed by classifying them into natural environment, location, Feng shui, and formal esthetics. As a result, the characteristics of the location type and the layout plan of the Qing dynasty imperial tombs were derived from the analysis of Feng shui shape, axis extension distance along the midaxial line, the width of the ridge, the formality of the facility layout according to the difference between the height of the starting point and the end point, the leftward direction of the tomb, and the space ratio of the 'entry space' - 'ritual space' - 'burial mound space', etc. In addition, it was possible to derive the facility arrangement characteristics of tombstones through the analysis of the types and the arrangement order of tombs facilities, as well as the distribution, quantity and types of stone figures, while also revealing some contrasting characteristics different from those of the Ming Dynasty. In addition, it was confirmed that the spatial division effect through the water system and the view effect of the view from the midaxial line and the vista are the representative view effect found in the Qing Dynasty imperial tombs along with the density contrast.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.32 no.6
• /
• pp.496-505
• /
• 2020

In the previous research, the effectiveness of resonator was confirmed through the numerical analysis on two cases with the use of existing resonator at the Mukho and Imwon ports located in the eastern coast of South Korea by discussing the reduction rates of 1983 Central East Sea tsunami, and 1993 Hokkaido Southwest off tsunami, respectively. In this study, the reduction rates of tsunami height with three different resonators, Type I, II-1, and II-2, at the Samcheok port were examined respectively through the numerical analysis using COMCOT model under the same condition as the previous study. It was discussed the spatial distribution of maximum height of tsunami, change of water level, and effectiveness of resonator with the presence of new types of resonator, and change of their sizes. As a result, the effectiveness of resonator was verified through the application of new types of resonator reducing about maximum 40% of tsunami height. In order to design the optimal resonator for the variety of site condition, it is necessary to research about the various cases applying different shape, arrangement, and size of resonator as further study.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.14 no.2
• /
• pp.50-54
• /
• 2010

Purpose: The uptake of $^{18}F$-FDG is often observed in normal cell of colon to patients who have non-insulin-dependent diabetes mellitus and had taken anti-diabetic drugs including Metformin in PET/CT scan. In this study, the region of colon was compared between the patients who took anti-diabetic drugs including Metfomin and other patients who took the other anti-diabetic drugs through SUV measurements. Materials and Methods: A hundred eighty patients were studied. 120 patients who have non-insulin-dependent diabetes mellitus (Including Metformin: 60, Excluding Metformin: 60) and 60 patients as a control group were composed. The patient fasted at least 6 hours before receiving an intravenous injection of 370-592 MBq (10-16 mCi) of $^{18}F$-FDG. Scanning from the base of the skull though the mid thigh was performed using the Discovery STe PET/CT Equipment (GE Healthcare, Milwaukee, WI, USA). The highest uptake region was measured SUV among ascending, transverse and descending colon. Results: The values of patients who took the anti-diabetic drugs including Metformin were $6.16{\pm}3.64$ g/mL, $4.41{\pm}2.94$ g/mL, and $5.46{\pm}2.44$ g/mL. The patients who took the anti-diabetic drugs which does not have Metformin were $3.05{\pm}1.39$ g/mL, $2.08{\pm}0.97$ g/mL and $3.15{\pm}1.85$ g/mL. The control group were $2.02{\pm}0.88$ g/mL, $1.68{\pm}0.87$ g/mL and $2.19{\pm}1.88$ g/mL. Conclusion: The effect of the intake of Metformin was observed from the SUV on region of large bowel in this study. Thus, it could be helpful for the results by identifying the ingredient of anti-diabetic drug before the examination and the possibility of interpretation of false positive will be reduced.

• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.1005_1006
• /
• 2009

본 논문에서는 단독부하형 삼상인버터의 디지털 전압제어기를 설계한다. 단독부하운전은 선형부하의 변동이나 비선형 부하에서도 안정적인 전압을 공급하는 것이 목적이다. 삼상 인버터를 선형 제어기로 제어하기 위해서 이상동기회전자표계로 제어하지만 두 개의 간섭항 때문에 MIMO 시스템으로 되어 해석적인 제어기를 설계하기 어려워 대부분의 연구에서는 시행착오법으로 제어기를 설계하였다. 본 논문에서는 삼상 인버터의 축변환시에 발생하는 간섭항의 영향을 상대이득행렬로 분석하여 간섭항의 영향을 분석하고 삼상 인버터 시스템을 SISO 시스템으로 만들어 전압제어기만을 갖는 최소 차수의 제어기를 해석적으로 설계하며 응답속도를 향상시키기위해서 오버슈트와 정정시간을 조절할 수 있는 극배치기법으로 설계한다. 설계한 제어기는 시뮬레이션과 실험을 통해서 강인성을 보인다.

• 전기의세계
• /
• v.34 no.1
• /
• pp.19-23
• /
• 1985

LQG로 설계된 시스템이 LQR의 보증된 안정감도를 갖도록 $K_{f}$를 조정하는 한 LTR기법을 살펴보았다. q가 0이라면 필터는 실제의 프로세서 잡음의 Q = Q$_{0}$라는 점에서 최적이다. 그러나 q의 값이 증가함에 따라 $K_{f}$는 증가되고 x over ^에 따라서 시스템의 동특성은 관측에 의해 수정되는 항보다 상대적으로 소홀히 취급되어진다. 따라서 출력 y에 포함되어 지지않는 x의 추정치 xover^은 그 실제값과 차이가 많이 나타날 우려가 생긴다. 또한 관측잡음이 xover^에 크게 영향을 미치므로 잡음을 배척하는 필터의 성질도 모호해질 우려가 있다. 그러나 안정강도의 관점에서는 크게 개선되어진다는 것을 알 수 있다. 실제 설계에 있어서는 이 장점과 단점들을 잘 trade off시키는 단계가 필요할 것이다. 또한 추정치 xover^를 얻는데 정상상태의 칼만 필터를 이용하지 않고 극배치(Pole Placement)방법을 사용함도 고려할 수 있으며 이에 따른 LTR도 흥미있는 분야가 될 수 있을 것이다.다.