• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2001년도 춘계학술대회 논문집
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• pp.43-48
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• 2001

Price of Used Vessel is Key-point of Ship trading but it is very troublesome part. Because it is different from the Seller and the Buyer's caculated price, It is appropriated by The Sellers and The Buyers' mutual agreement. In case of the Buyers. it is difficult in calculating price of used ship without entrusting the ship broker, beca- use evaluation method of secondhanded vessel has not formulated and the ship broker has experientially computed Remain Value of used vessel. For this work, structure of ship trading market, trading flow, the factor of price composition and Affecting factor of price is reviewed, and it examined relationship with price. On these base, a computer software integrated database system and object-oriented technique is developed. The developed system is expected helpful to evaluation of remain value of the used vessel.

• Journal of Multimedia Information System
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• 제7권4호
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• pp.269-276
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• 2020

The small craft including jet-board for leisure are commonly smaller than the general commercial vessels. For the floating vessel, the motion analysis is significantly important component to design the shape. It is, however, hardly predicting its behavior by using conventional boundary element method due to violating small amplitude assumption for potential theory. The computational fluid dynamics method can afford to simulate such small craft, but its grid system was not able to calculate motion, because movable body disturbs the grid system by confliction. The dynamics fluid body interaction model with over-set mesh system can be dealt with movable floating body under irregular ocean wave. In this study, several cases were considered to reveal that DFBI is essential method to predict floating body motion. The single phase simulate was conducted to establish the shape perfection, and then the validated vessel was simulated with ocean waves weather DFBI option on or off. Through the comparison, the results between the cases of DFBI on and off shows significantly difference. It was claimed that the DFBI was necessary not only to calculation body motion, but also to predict accurate drag and lift force on the floating body for small size craft.

• 대한한의학회지
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• 제28권1호통권69호
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• pp.224-236
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• 2007

Background : Chunghyul-dan is a combinatorial herbal medicine; previous studies reported it had therapeutic effects for microangiopathy, a major part in the progression of small vessel disease, as well as having anti-hypertensive, anti-hyperlipidemic, anti-apoptotic, anti-oxidative, and anti-inflammatory activities. Therefor, we examined the inhibitory effect of Chunghyul-dan on stroke recurrence in patients with small vessel disease. Methods : We prescribed Chunghyul-dan at 600 mg a day to patients with small vessel disease, and monitored stroke recurrence, drug compliances, and adverse effect for 1 year. We then performed follow-up brain MRI to find new vascular lesions after 1 year of Chunghyul-dan medication. For the subjects lost to follow-up, we assessed their prognosis after 1 year by telephone. Results : There were 73 subjects treated with Chunghyul-dan for 1 year; new vascular events were found in 3. Of the 85 subjects lost to follow-up, fifty four could be contacted, and eight of them had stroke recurrence. One year of Chunghyul-dan medication reduced the odds ratio of stroke recurrence by 75% compared to the subjects lost to follow-up and the rate increased to 88%, when adjusted for other relevant risk factors for stroke recurrence. These reductions were much higher than those of aspirin and other kinds of conventional anti-platelets. There was no adverse effect in any of the study subjects. Conclusions : We suggest Chunghyul-dan could be useful for inhibition of stroke recurrence. Further study with a randomized controlled trial is needed to confirm this suggestion.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 추계학술대회 논문집
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• pp.527-532
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• 2011

Whirling vibration in severe cases may result in shaft cracking and typically gap sensors are utilized to confirm its values under the outside underwater of ship. The bending stress value causing whirling vibration on the propulsion shafting system of a 40-ton small vessel was verified by theoretical analysis and its vibration measurement. However, because of underwater condition, the accuracy for this measurement method is presumed low. In this study, the strain gauge basic principle and the bending stress calculation method are considered. The relationships are then applied for obtaining the whirling vibration of the 40-ton small vessel. As a result, a new method in estimation of whirling vibration is reached and suggested.

• 해양환경안전학회지
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• 제25권7호
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• pp.867-873
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• 2019

2019년 8월을 기준으로 우리나라에서 소형선박의 범주에 포함될 수 있는 30톤 미만의 선박은 3,782척으로 전체 등록선박 8,890척 대비 42.5 %를 차지한다. 문제는 소형선박의 종사자들이 주로 외래어에서 기형적으로 파생된 비표준어를 많이 사용함으로써 선내 의사소통의 단절, 해기사 면허시험이나 해기 관련 교육수강 시 의사소통의 어려움을 겪는 등 많은 문제에 직면하고 있으며, 이는 소형선박 종사자들의 직무능력 저하로 이어지고 있다는 점이다. 이에 본 연구에서는 소형선박 종사자들의 사용용어를 면밀히 분석하고, 이를 바탕으로 표준화 방안을 제안하였다. 사용용어 분석을 위하여 해기사 면허시험의 기출용어, 소형선박 교육교재의 다빈도 용어를 식별하였고, 이에 해당하는 비표준어를 조사하였다. 조사된 내용을 토대로 전문가 회의를 개최하여, 주요 용어에 대한 잘못된 일본식표기, 영어표기, 표준어를 제시하여 어느 표기에 가장 친숙한지에 관해 설문을 시행하여 분석하였다. 설문 분석결과 항해 용어의 경우 비교적 표준어 사용의 비율이 높으나, 기관 용어의 경우 잘못된 일본식 표기를 더 많이 사용하고 있으며, 연령별, 톤수별 분석결과도 일본식 표기를 전반적으로 많이 사용하며, 영어식 표기의 사용빈도는 낮은 것으로 분석되었다. 이를 토대로 소형선박 종사자의 표준어 사용을 위한 단기 및 장기방안을 제안하였고, 이에는 소형선박 종사자들이 사용하는 용어에 대한 표준어사전의 제작, 표준어 사용에 대한 중요성 홍보, 교육기관을 통한 적극적인 교육, 외국인 선원들을 대상으로 하는 한국어교육에 대한 체계적인 준비 및 이행 등이 포함된다.

• 한국인터넷방송통신학회논문지
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• 제17권2호
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• pp.69-74
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• 2017

최근 연안지역에 선박 통항량이 증가하고 있어, 그에 따른 해양사고도 증가하고 있다. IMO에서 안전운항을 위하여 안전 장비를 의무적으로 장착하도록 권고하고 있다. 대부분의 중대형 선박은 거의 안전운항 장비를 구비하고 있지만, 소형 선박은 선주의 재정상 어려움 또는 무관심 때문에 구비하지 않는 경우가 많이 있다. 그러므로 여안 지역에서 소형선박의 안전을 위하여, 좌초, 침몰, 그리고 충돌 등과 같은 해양 사고를 미리 예방하거나 또는 사고 발생 시 신속히 대처할 수 있어야 한다. 이 논문에서는 이와 같은 기능을 수행하는 소형선박용 안전 장비를 개발하였다. 이 장비는 선원의 스마트폰 및 저렴한 전용 단말상에 이런 상태를 표시해 주고 동시에 이런 상태를 제어센터와 인근에 있는 선박에 전송함으로써 무방비 상태에 있는 소형 선박의 안전을 상당히 보장해 줄 수 있다.

• 해양환경안전학회지
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• 제27권7호
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• pp.1023-1030
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• 2021

중앙해양안전심판원(2019)에서 발표한 최근 5년의 해양사고통계자료에 따르면 충돌사고의 대부분은 20톤 미만의 어선에서 발생하고 있으며 전방 부주의, 경계 소홀 등의 운항과실로 인한 사고가 주요 원인으로 나타나고 있다. 이러한 사고 방지를 위해 운항자를 대상으로 훈련 및 교육을 강화하고 있지만 충돌사고는 빈번히 발생되고 있으며 충돌 사고를 줄이기 위한 기술적인 방안 또한 지속적으로 개발중에 있다. 본 연구에서는 고속 활주형 소형 선박에 WAVE 통신 기술을 적용하여 선박 간 거리, 속도, 방위에 기반한 조우 상황을 고려하여 충돌 회피 동작이 가능한 제어 알고리즘을 개발하였으며, WAVE 통신-제어기를 결합하여 충돌 회피 시스템을 구축하였다. 그리고 충돌 회피 동작의 검증을 위해 두 소형 선박간의 정면, 추월, 교차의 3가지의 조우 시나리오에 대해서 시뮬레이션을 수행하고 실선 시험을 통해서 충돌 회피 알고리즘을 검증하였다.

• Journal of Forest and Environmental Science
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• 제8권1호
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• pp.51-66
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• 1992

This study was carried out to investigate the micromorphology of vessel wall sculpture such as shape of perforation plate, perforation rim, steepness of perforation plate, occurrence of vestured pit, warty layer and ray-vessel pitting on 13 species of Fagaceae in Korea. The results were summarized as follows ; 1. In the species examined, all sample species except Fagus crenata var. multinervis have simple perforation plate. But Fagus crenata var. multinervis has simple and scalariform perforation plate (it was called to combination perforation plate) in a tree stem. 2. The shapes of perforation rim could be classified into five types; Type A without tail, Type B with small tail on both sides, Type C with long tail on both sides, Type D with tail only one side and Type E with the very short interval between perforations. Among five types, Type Band C have higer frequency of distribution than the others. 3. The steepness of perforation plate measured was about 20 degree on pore zone and 43 degree on outside parts of pore zone. 4. Species with vestured pit were Q. aliena, Q, dentata, Q. variabilis, Fagus crenata var. multinervis, Castanopsis cuspidata var sieboldii, Q. acuta, Q. stenophylla, and Q. glauca. But the extent of vesturing was very slight and vestured pits were observed mainly in ray-vessel pit of some vessel elements. 5. Species with warty layer on the inner surface wall of all vessel elements were Q. acuta, Q. stenophylla, Q. glauca, Fagus crenata var. multinervis and species with warty layer of some vessel elements were Q. aliena, Q, dentata, Q. variabilis, Castanopsis cuspidata var. sieboldii. 6. Species with palisade ray-vessel pit were Q. acuta, Q. stenophylla, Q. glauca, Castanea crenata, Castanea bungeana, Q. aliena, Q. serrata, Q. mongolica, and species with scalariform ray-vessel pit was Fagus crenata var. multinervis and species with oval ray-vessel pit were Q, dentata, Castanopsis cuspidata var sieboldii.

• International Journal of Naval Architecture and Ocean Engineering
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• 제12권1호
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• pp.491-500
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• 2020

The present study proposes a time domain model for the Vortex-induced Vibration (VIV) simulation of a catenary riser under the combination of the current and oscillatory flow induced by vessel motion. In this model, the hydrodynamic force of VIV comprises excitation force, hydrodynamic damping and added mass, which are taken as functions of the non-dimensional frequency and amplitude ratio. The non-dimensional frequency is related with the response frequency, natural frequency, lock-in range and the fluid velocity. The relatively oscillatory flow induced by vessel motion is taken into account in the fluid velocity. Considering that the added mass coefficient and the non-dimensional frequency can affect each other, an iterative analysis is conducted at each time step to update the added mass coefficient and the natural frequency. This model is in detail validated against the published test models. The results show that the model can reasonably reflect the effect of the added mass coefficient on the VIV, and can well predict the riser's VIV under stationary and oscillatory flow induced by vessel motion. Based on the model, this study carries out the VIV simulation of a catenary riser with harmonic vessel motion. By analyzing the bending moment near the touchdown point, it is found that under the combination of the ocean current and oscillatory flow the vessel motion may decrease the VIV response, while increase the excited frequencies. In addition, the decreasing rate of the VIV under vessel surge is larger than that under vessel heave at small vessel motion velocity, while the situation becomes opposite at large vessel motion velocity.

• 한국산업융합학회 논문집
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• 제24권6_2호
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• pp.899-908
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• 2021

It is expected that the global market for vessel repair and remodeling will grow up to the scale of about 25 billion dollars by 2023. Korea's shipbuilding industry is leading the world with its international competitiveness in design and production technology. The actual status of vessel repair industry, however, is poor as there are only two or three companies for vessel repair that can deal with large vessels in the area of Gyeongnam. The reason is that civil complaints are filed severely about environmental problems and environment-related regulations are so strict that it is fairly hard to get governmental approval for the operation of a vessel repair workplace. Domestic vessel repair companies mainly target small- and medium-sized vessels. There are only few workplaces that can carry out regular examination or repair work on large vessels such as LNG vessels, and due to the high price of vessel repair, most of the domestic repair work on large vessels including LNG vessels tends to be snatched by markets in Southeast Asia or China. Despite the tremendous domestic demand of Korea that has established the world's first shipbuilding industry and world's sixth biggest harbor infrastructure, its vessel repair industry can be said to be in very poor condition. In order to vitalize vessel repair industry, this study is aimed to analyze the environmental influence of vessel repair workplaces in Gyeongnam where vessel repair companies are concentrated and suggest standard processes by analyzing vessel repair processes precisely.