• 한국식생활문화학회지
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• 제29권6호
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• pp.499-510
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• 2014

This study examined the food culture of the Koryo Dynasty during the early 13th century based on the records of wooden tablets and marine relics from the 1st and 2nd ships of Mado wrecked at sea off Taean while sailing for Gaegyeong containing various types of grain paid as taxes and tributes. The recipients of the cargo on the 1st ship of Mado were bureaucrats living in Gaegyeong during the period of the military regime of the Koryo Dynasty, and the place of embarkation was the inlet around Haenam (Juksan Prefecture) and Naju (Hoijin Prefecture) in Jolla-do. On wooden tablets were recorded 37 items of rice, cereal, and fermented foods. The measures used in the records were seok [石-20 du (斗)] for cereal, seok [15 du, 20 du] for fermented soybean paste, and pot (缸) and volume (斗) for salted fish. The places of embarkation on the 2nd ship of Mado were Jeongeup (Gobu Prefecture), Gochang (Jangsa Prefecture, Musong Prefecture), etc. On wooden tablets were recorded 29 items of rice, cereal, fermented foods, seasame oil, and honey. The volume measure for yeast guk (麴), the fermentative organism for rice wine, was nang [囊-geun (斤)], and the measure for sesame oil and honey, which were materials of oil-and-honey pastries and confections, was joon (樽-seong, 盛). Honey and sesame oil were luxury foods for the upper-class people of the Koryo Dynasty, and they were carried in high-quality inlaid celadon vases in Meibyung style. Food names and measures written on wooden tablets and actual artifacts found in the 1st and 2nd ships of Mado are valuable materials for research into agriculture, cereal, and fermented foods of the Koryo Dynasty in the early 13th century. Besides, relics such as grains and bones of fish and animals from the Koryo Dynasty are expected to provide crucial information usable in studies on food history of the Korean Peninsula.

• 한국항해학회지
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• 제1권1호
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• pp.27-44
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• 1977

The Maneuvering Indices of a ship are the values that decide the quantity of her motion in turning when her rudder is turned over to an angle to the starboard or the port. They consist of two kinds of indices, one of which is called index K and the other, index T. Index K decides a ship's turning ability and index T does the length of time delay of a normal turning motion after her rudder has finished the turn of an ordered angle. Generally, the values of the indices are calculated through some mathematic formulas with figures of her heading degrees recorded at a fixed time intervals during her Z test. The values of the same kind index of a ship appear differently according to the ship'sspeed, trim, rudder angle and loaded condition, etc. In this paper, the author analyzed all the amthematic formulas required to calculate the values of the indices in their forming process and examined them from the point of mathematics and dynamics and also actually figured out the values of maneuvering indices of the M.S. "HANBADA", the training ship of Korea Merchant Marine College through her Z test. The author supposed a case in which two same typed ships as the "HANBADA" in size, shape and conditions were approaching each other in meeting end on situation and each ship turned her rudder hard over to the starboard respectively when they approached to the distance of 3 times as long as the ship's length. The author worked out mathematic formulas calculating forward and transverse ship's motions within the above mentioned situation for the quantative analysis of the collision avoding action to certify whether they are in collision status or not. Applying the calculated values of the maneuvering indices of the "HANBADA" to the motion calculating formulas, the author found out the two ships were passing over each other with the clearing distance o 39m between their port quarters. With the above mentioned examinations and explanations, the author demonstrated that a ship's motion in any collision avoiding action can be shown with quantities of time and distance within reliable limit.istance within reliable limit.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 Asia Navigation Conference
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• pp.113-120
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• 2004

Considering the present and expected demand for human resources by the maritime community, its quantity and quality depend on the number of the ships and the technology applied to them. Scientific and economic developments in this community bring the intensive use of modem technology for many of ships operation. Generally it effects to reduce the quantity of manpower, while it increases the requirement of qualifications of human resources to utilize such advanced technology. Considering above, the maritime education, training and research activities should be revised and updated according to the demand of the community. Because of a difference between the transition of the demand for the human resources and development of the maritime education, training and research activities, there are two most common questions as “What to teach” and “How to teach”. The first question has been asked for many years. The contents of maritime education and training are always related to the existing maritime knowledge and technology and should be updated with consideration of changes of the demand namely “Globalisation of maritime community”. It brings globalisation of the maritime education, training and research activities. The second question is still keeping us busy to look for the best way. Presently traditional methods are used together with new system, while the use of sophisticated simulation, communication and information systems etc. and it is changing our understanding on teaching. This paper introduces the new role of Maritime Institutions from the viewpoints of the maritime education. training and research activities. The role of guide for seafarers and maritime companies is always essential and the concepts such as “Refreshment Training”, “On the Job Training”, “Lifelong” or “Continuous Training” bring new understanding to the training period, trainee's age and position. As a result, the maritime institutions should be ready for their new role, which is, in brief, guiding the maritime society, recommending and providing new learning environments, organising research and developments, performing the education, training and assessment, improving existing methods and developing new methods of the education, training and assessment.

• 수산해양기술연구
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• 제43권3호
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• pp.222-231
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• 2007

This paper represents a basic statistical examination on the navigability of ocean-going ship from the point of estimating the time lasting period when propeller racing occurred by using the basic probability theory and the statistics. The propeller racing is one of the most important seakeeping qualities in relation to the safety of the main engine and shafting system. The trend of the racing has been mainly investigated in order to estimate allowable maximum propeller diameter, operation of ocean-going ships, etc.. In those studies, the propeller racing generally and mainly means the situation (propeller exposed) in which the relative motion amplitude between ship hull and wave surface would exceed a depth of point in rotary disk propeller. Therefore, it seems that the magnitude of the amplitude and its exceeding frequency of propeller racing have been examined as a principal subject of study as usual. However, the time during which the amplitude exceeds the depth of point, that is, the propeller exposes in the air, must be also one of most important factor affecting the trend of propeller racing. Then, this paper proposes a new practical method for estimating the time lasting of exposed propeller related to propeller racing in rough-confused seas on the basis of the linear strip theory and the statistics. And, numerical examples of estimating the propeller racing probability are given for four wide ship forms. Finally the usefulness of the proposed method for predicting propeller racing based on the time lasting period is discussed.

• 대한조선학회논문집
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• 제32권4호
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• pp.27-37
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• 1995

본 연구에서는 대양을 항행하는 선박의 자동조타 시스템의 정량적 평가, 해석을 위해서 추진 에너지 손실의 관점에서 성능평가지수를 도출하였다. 그 결과 성능평가지수는 침로편차, 타각, 회두각속도의 제곱평균치로써 구성됨을 밝혔고, 아울러 각 제곱평균치의 계수는 선박의 유체역학적 특성에 의해서 결정됨을 알 수 있었다. 또한 성능평가지수는 자동조타 시스템에 불규칙 외란이 입력으로 작용하였을 때, 주파수 응답법과 시뮬레이션 기법에 의해서 정도 높게 계산될 수 있음을 밝혔다. 대표적 해상 상태에서 광석운반선과 소형 어선에 대한 시계산 결과, 주파수 응답법은 작은 외란하에서 시스템이 선형인 경우에는 유용하지만, 비교적 큰 외란하에서 또는 시스템 내부에 비선형 요소가 있는 경우에는 시뮬레이션 기법이 보다 정확하고 유용함을 알 수 있었다.

• 대한조선학회논문집
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• 제47권5호
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• pp.689-696
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• 2010

Bulbous bow is one of the important design factors on the design of fore-body hull form. Using the interference technique of ship waves, the bulbous bow can decrease the wave resistance of ship. Recently, the goose neck bulb is applied mainly for high speed vessels like passenger ships and ferries etc.. Also, the goose neck bulb is applied for relatively high speed merchant vessels like container ships and LNG carriers. However, existing research papers about the goose neck bulb are not enough as reference data for the design of bow hull form. In this study, numerical calculations are carried out to investigate the bow wave characteristics of a high speed ferry with a normal high nose bulb or a goose neck bulb. By comparing the pressure distributions on the hull surface and the wave systems near the bow, the features of wave resistance reduction are discussed. Also, Numerical calculations were carried out for a series of goose neck bulbs to figure out the optimum bulb size. The maximum reduction rate of pressure resistance for the fore-body is achievable up to 8% by adopting the goose neck bulb in the present calculation.

• 수산해양기술연구
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• 제44권3호
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• pp.229-238
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• 2008

This paper describes on the consolidation of AIS and ARPA radar positions by comparing the AIS and ARPA radar information for the tracked ship targets using a PC-based ECDIS in Busan harbor, Korea. The information of AIS and ARPA radar target was acquired independently, and the tracking parameters such as ship's position, COG, SOG, gyro heading, rate of turn, CPA, TCPA, ship s name and MMSI etc. were displayed automatically on the chart of a PC-based ECDIS with radar overlay and ARPA tracking. The ARPA tracking information obtained from the observed radar images of the target ship was compared with the AIS information received from the same vessel to investigate the difference in the position and movement behavior between AIS and ARPA tracked target ships. For the ARPA radar and AIS targets to be consolidated, the differences in range, speed, course, bearing and distance between their targets were estimated to obtain a clear standards for the consolidation of ARPA radar and AIS targets. The average differences between their ranges, their speeds and their courses were 2.06% of the average range, -0.11 knots with the averaged SOG of 11.62 knots, and $0.02^{\circ}$ with the averaged COG of $37.2^{\circ}$, respectively. The average differences between their bearings and between their positions were $-1.29^{\circ}$ and 68.8m, respectively. From these results, we concluded that if the ROT, COG, SOG, and HDG informations are correct, the AIS system can be improved the prediction of a target ship's path and the OOW(Officer of Watch) s ability to anticipate a traffic situation more accurately.

• 한국컴퓨터정보학회논문지
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• 제25권11호
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• pp.147-155
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• 2020

체계지원 소프트웨어는 함정 전투관리체계를 구성하는 소프트웨어 중의 하나로 모든 함정의 전투관리체계에 탑재되지만 기능 변경이 거의 일어나지 않는 특성을 가진다. 하지만, 이러한 특성에도 실제로는 신규함정 적용 시 장비 변경 등으로 인한 소프트웨어 수정이 불가피하게 이루어진다. 이러한 소프트웨어의 수정은 소프트웨어 신뢰성 시험 등의 작업을 초래하며, 개발 비용 증가의 핵심요인으로 작용한다. 본 논문에서는 기존 체계지원 소프트웨어의 구조를 분석하여 이를 보완할 수 있는 체계지원 표준화 아키텍처를 설계하였다. 휘처 모델(Feature Model)을 통해 체계지원 소프트웨어의 공통요소와 가변요소를 도출하고, 화이트 박스 재사용(White-Box Reuse)을 적용하여 소프트웨어 설계를 개선하였다. 또한, 기존 체계지원 소프트웨어와 개발 요소 및 신뢰성 시험 수행 시간을 비교하여 새로운 아키텍처의 효과성을 검증한 결과를 제시하였다.

• 수산해양기술연구
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• 제56권2호
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• pp.163-171
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• 2020

Engaged in trawling in limited fishing grounds with a number of fish schools could cause collisions between fishing vessels. Therefore, providing accurate maneuver information according to the situation could be regarded as essential for improving seafarers safety and fishing efficiency as well as safety of navigation. It is difficult to obtain all maneuver information through sea trial tests only, so a method through empirical formula is necessary. Since most empirical formulas are developed for merchant ship types, especially the characteristics of hull shape parameter like C_bB/L and dC_b/B etc. are clearly different between fishing vessels and merchant ships, this could occur estimation errors. Therefore, in this study, the authors have selected target fishing vessels and merchant ships and analyzed the characteristics of hull shape parameter according to the ship types. Based on this analysis, the empirical formula developed for the merchant ship type has applied to the target fishing vessels; it has verified through the turning motion simulation that the estimation error could be generated. In conclusion, it is necessary to include the characteristics of the hull shape parameter of fishing vessels in the empirical formula in order to apply the empirical formula has developed for merchant ship types to fishing vessel types.

• 한국음향학회지
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• 제29권8호
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• pp.497-503
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• 2010

본 논문은 여객선용 HVAC 시스템 목업을 구축하여 HVAC 요소의 성능평가를 수행한 결과를 다루었다. 측정은 룸 유니트 (Room Unit), 소음기 등 6가지 종류에 대해 이루어졌으며 여러 유량에 대해 삽입손실을 측정하였다. 소음기 직경이 작고 유량이 클수록 유동소음이 커져서 소음저감효과를 방해하지만, 직경이 커질수록 유동소음의 효과는 작아지고 삽입손실은 최대 25 dB까지 나타남을 확인하였다. 디퓨저 형태의 룸 유니트는 대체로 삽입손실이 0 - 10 dB 이지만 노즐 형태는 삽입손실이 최대 -15 dB 까지 소음이 커질 수 있음을 확인하였다. 또한 덕트 배열에 따라 최대 2 dB 까지 실내소음이 차이날 수 있음을 보였으며 각 룸 유니트에 동일한 유량이 배출하도록 조절하는 것이 보다 낮은 소음레벨을 얻을 수 있음을 확인하였다.