• International Journal of Naval Architecture and Ocean Engineering
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• 제10권3호
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• pp.235-249
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• 2018

The Artificial Neural Network (ANN) model has been known as one of the most effective theories for automatic ship berthing, as it has learning ability and mimics the actions of the human brain when performing the stages of ship berthing. However, existing ANN controllers can only bring a ship into a berth in a certain port, where the inputs of the ANN are the same as those of the teaching data. This means that those ANN controllers must be retrained when the ship arrives to a new port, which is time-consuming and costly. In this research, by using the head-up coordinate system, which includes the relative bearing and distance from the ship to the berth, a novel ANN controller is proposed to automatically control the ship into the berth in different ports without retraining the ANN structure. Numerical simulations were performed to verify the effectiveness of the proposed controller. First, teaching data were created in the original port to train the neural network; then, the controller was tested for automatic berthing in other ports, where the initial conditions of the inputs in the head-up coordinate system were similar to those of the teaching data in the original port. The results showed that the proposed controller has good performance for ship berthing in ports.

• 한국항만경제학회지
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• 제20권2호
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• pp.35-52
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• 2004

The purpose of this paper is to measure the competition power of administration service in Korean Seaports by using the scores of customer satisfaction for administration service investigated yearly from 2000 to 2003 by Ministry of Maritime Affairs & Fisheries. And also, this paper shows the competition power of Korean seaports in terms of efficiency by using DEA(data envelopment analysis) method after measuring the change of productive efficiency scores subject to including and excluding the scores of customer satisfaction for administration service as output variable. The empirical main results of this paper are as follows: First, the efficiency scores of the Ports of Donghae, Gunsan, Jeju, Yeosu, Masan, and Pohang have worsened if the customer satisfaction score is excluded as output variable. Therefore these ports have been influenced by the score of customer satisfaction more positively. Second, the changes of the ranking order by measuring the average efficiency scores of each ports subject to including and excluding the scores of customer satisfaction for administration service as output variable are as follows: Busan(9-->7), Incheon(6-->6), Yeosu(1-->4), Gwangyang(4-->3), Masan (10-->9), Ulsan(5-->5), Donghae(8-->11), Gusan(12-->12), Mogpo(3-->2), Pohang(11-->10), Jeju(7-->8), Daesan(2-->1).

• 한국안전학회지
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• 제21권4호
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• pp.7-12
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• 2006

Recently, the application of transverse ventilation system with oversized exhaust ports has been increased in bidirectional road tunnel in order to improve smoke exhaust ability. Therefore, in this study, for decision of the optimal smoke exhaust rates in the transverse ventilation system, several standards of nations are compared and numerical simulations with variations of exhaust flow rates are carried out in terms of smoke spread distance by FDS ver. 3.1. As results, in the case of no internal longitudinal air velocity in tunnel, the smoke exhaust rate of $80m^{3}/s$ (the smoke generation rate at HRR of 20MW) is sufficient enough to limit the smoke spread within 250m in 6 minutes after the fire. However, in the case of the internal longitudinal air velocity at 2.5m/s, the smoke exhaust rate should be increased $130m^{3}/s$.

• 응용통계연구
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• 제22권6호
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• pp.1167-1176
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• 2009

항만이나 공항의 소유구조에 대한 효율성 분석은 지금까지 서로 엇갈리는 결과를 제시하고 있다. 즉, 민영화 또는 공영화로 인한 효율성 효과가 자료 또는 분석 방법에 따라서 일치된 결과를 보여주지 않고 있다. 본 논문은 국내의 항만이 포함된 국제 항만 교역데이터베이스를 기반으로 베이지안 확률적 프런티어 모형을 적용하여 항만의 소유 구조에 따른 효율성 분석을 하였다. 소유 구조는 Tongzon과 Heng (2005)의 방법을 따랐으며 제안된 몇 가지 모형과 그들의 모형을 DIC 통계량을 이용하여 비교하였다. 베이지안 추론에 필요한 MCMC 방법은 Griffin과 Steel (2007)에서 소개된 WinBUGS 프로그램을 이용하여 구현하였다.

• 한국항만경제학회:학술대회논문집
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• 한국항만경제학회 2007년도 정책세미나 및 국제학술대회
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• pp.493-514
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• 2007

A Port is, one of the important infrastructures, the terminal to connect between land and sea and exerts influences on the development of nation and local area. Accordingly government and privates are making an investment in port facilities in order to raise its competitive power. Due to the economic growth of China and the geographic advantage that Gunsan and Janghang port are close to China, recently traffic with China is rapidly increasing and the role of Gunsan & Janghang ports as a gateway port of west costbecame more important. There, however, remains that Gunsan and Janhang port still don't equipped with enough facilities and strategies to handle increasing traffic. The purpose of this paper is to analyze O/D data of Gunsan-Janghang Port and present the result of O/D as preliminary data. O/D data of Gunsan and Janghang had been analyzed by kinds of cargoes and from/to China's ports and this paper suggests to the competitive strategies of Gunsan and Janghang port to attract cargoes from/to China particularly.

• 한국해양공학회지
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• 제13권3B호
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• pp.29-37
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• 1999

Ventilation of the marine engine room is very important for the health of the workers as well as the normal operation of machines. To find proper ventilation conditions of this engine room, numerical simulation with standard k-${\epsilon}$ model was carried out. In the present study, the marine engine room is separated to two floors with porus horizontal partition and considered as a closed space with a heat source and forced ventilation ducts. The porosity of horizontal partition is found to be important. For the engine room with 2 supply ports & 2 exhaust ports, the increasing of the porosity of horizontal partition is effective to reduce the recirculation flow zone in the second floor. When the engine room is ventilated with three supply air ports & one exhaust port, the increasing of the porosity of horizontal partition is effective to reduce the recirculating flow zone in the exhaust air area, but there is a possibility of local extreme heating at the lower side of engine near bottom.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 Asia Navigation Conference
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• pp.203-207
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• 2004

Yangtze River channel is in natural condition for a long time. There are more to be done in grade of navigation and transport. Since 1980's the rate of vessel in JiangSu channel is going up every year, especially for ocean vessels. Meanwhile, the serious factors such as no sailing at night have become a battlement causing the long period for vessels, high cost for shipowners, lower competitiveness for JiangSu ports along the Yangtze River. It also can not meet the port logistic development. After the Ships' Routeing in JiangSu has been carried out. It has improved the safety of navigation in JiangSu area and reduced the risk of pollution or other damage to the marine environment caused by ships colliding or anchoring in or near JiangSu channel. By analyzing, compareing, calculating and model forecasting. The main focus of the paper is put on the study the development of port, channel in JiangSu and efficiency in many fields. Navigation efficiency of the sailing at night; Safety efficiency of reducing the risk by ships; More efficiency of the higher cargo volumes of the other ports in Yangtze River with the increase cargo volume of JiangSu ports along Yangtze River. The purpose of this study is: To get the social and economical efficiency after the Ships' Routeing in JiangSu has been carried out. Also the role of the Ships' Routeing of JiangSu in the development of Port and Channel.

• 한국화재소방학회논문지
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• 제22권2호
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• pp.38-43
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• 2008

최근에 양방향 도로터널에서 배연효율의 증가가 요구됨에 따라 대배기에 의한 횡류식 양방향터널 배연시스템 적용이 증가되었다. 본 연구에서는 FDS Ver4.0을 사용한 수치해석을 통해 배연량과 화재강도를 변화시켜 최적배연조건을 도출하였다. 결과로, 터널 내부로 외부기류가 유입되는 경우에는 배연량을 증가시켜야 하는 것으로 나타났으며 화재지점으로 2.5m/s의 속도로 외기가 불어올 때 연기가 250m 이내로 제어되는 대배기구의 배연용량은 $244.8m^3/s$의 값으로 제어되어야 한다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2007년도 제29회 추계학술대회논문집
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• pp.233-236
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• 2007

멀티포트 하이브리드 로켓 고체연료 그레인의 열민감도에 관한 연구를 수행하였다. 고온의 비반응 유동의 포트를 통과하며 연료 그레인으로 열전달 시, 연료 그레인 내부의 온도 분포 변화를 비정상 열해석을 통해 계산하였다. 계산은 총 9개의 포트 반경에서 수행되었으며, 연료 내부 온도가 민감하게 거동하는 임계 포트 반경을 결정하였다. 열에 민감하게 반응하는 임계 포트반경 이후는 고체 폴리머 연료의 구조상의 취약점이 발생할 것으로 판단되므로, 임계 포트반경은 설계 시 중요한 고려대상으로 사용될 것으로 예상된다.

• 한국항만경제학회지
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• 제24권3호
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• pp.125-146
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• 2008

본 연구에서는 광양항이 동북아 물류중심항만으로 성장하기 위한 하나의 방안으로 e-비즈니스 환경에 따른 웹사이트를 활용한 항만마케팅 전략을 제시하고자 한다. 즉, 항만을 e-비즈니스 관점에서 접근하여 단순히 웹사이트를 구축하여 대(對)고객 서비스를 지향하는 것이 아니라, 웹사이트 6C 요소에 따른 효율적인 운영방안을 제시하는데 목적이 있다. 반면, e-비즈니스 환경에서 웹사이트를 활용한 항만 활성화 방안에 관한 연구는 매우 드문 실정이다. 일부 항만마케팅에 관한 선행연구의 경우 이론적인 전개와 Off-line적 4P 전략을 제시하고 있어 e-비즈니스 환경에 따른 한계점을 가지고 있다. 그리고 6C 전략도 모델의 설정과 비교분석 과정에 있어 다소 구체성이 부족함을 보이고 있다. 이에 본 연구에서는 선행연구의 한계점을 보완하여 체계적으로 이론을 정립했으며, 현재 광양항 관련 3개의 웹사이트 운영 현황을 6C를 중심으로 비교 분석하였다. 그리고 분석결과를 토대로 6C 전략별 운영방안을 제시하고자 한다.