• 해양환경안전학회지
• /
• 제27권1호
• /
• pp.67-73
• /
• 2021

본 연구는 충돌 사고 중에서 정박지에서 대기하고 있는 선박과 이 정박지를 통항하는 선박 간 충돌사고가 자주 발생함에 따라, 정박선 사이를 통항하는 선박의 충돌위험을 예측할 수 있는 모델을 개발하기 위한 기초 연구로 통항 선박의 안전 영역을 도출하는 것이 목적이다. 이를 위해 우리나라 최대 항만인 부산항 남외항 정박지를 대상 해역으로 선정하고 정박선이 가장 많이 대기한 기간 VTS(Vessel Traffic Service) 항적 자료를 추출하여 분석하였다. 정박선 사이를 통항하는 선박의 길이(L)를 기준으로 정박선과 어느 정도의 안전한 거리(D)를 두고 통과하는지를 알기 위하여 통항 선박의 방위별 D/L 비를 구하였다. D/L 비 분포의 평균 domain을 기준으로 기존 선박 domain 범위 안으로 정박선이 존재할 비율을 분석하여 VTS 관제사의 위험 정도를 반영한 domain을 도출하였다. 추후 연구로는 정박선 사이의 최소 안전거리인 Domain-watch와 정박지 통항 선박의 안전 domain을 활용한 정박지 통항 선박의 충돌위험도 평가 및 분석을 하고, 이를 통해 VTS가 정박지를 좀 더 효율적이고 안전하게 관리하기 위한 모델을 개발하고자 한다.

• 해양환경안전학회지
• /
• 제26권5호
• /
• pp.445-453
• /
• 2020

선박의 안전한 접·이안을 담당하는 예선은 항만의 안전하고 효율적인 운영을 위한 여러 요소들 중 무엇보다 중요한 사항이라고 할 수 있다. 그러나 항만의 특징에 따라 보유해야 하는 적정 예선 척수 및 규모에 대한 연구가 부족한 상황이고, 이로 인하여 관계자 간 분쟁이 자주 발생하고 있는 실정이다. 이에 본 연구에서는 울산항을 중심으로 시뮬레이션 기법을 사용하여 예선의 적정 척수 및 예선 마력 비율을 제시하였다. 먼저, 시뮬레이션 구축을 위한 첫 번째 과정으로 항만 입·출항 및 예선 운영 시스템을 설계하였다. 다음으로, 모델링 시 정의한 입력 변수는 울산항의 2019년 선박 입·출항 데이터를 조사하여 도출하였으며, ARENA 소프트웨어에 입력 가능한 형태로 표준화하였다. 그리고 선박의 입·출항 프로세스를 설계하고, 이를 ARENA 모델로 구현하였다. 마지막으로 6가지의 시나리오에 대한 시뮬레이션 수행 결과, 울산항의 예선 척수를 42척으로 조정할 경우 효과적인 예선 운영이 가능한 것으로 도출되었다.

• 한국항해항만학회지
• /
• 제30권9호
• /
• pp.755-762
• /
• 2006

When we consider to develop a new harbor, the most important factor, we think, is the lowest water depth of waterway and approaching channel for safe navigation of vessel. The existing harbors have been being dredged to meet the international trend of jumbo sized vessels by adopting the new design criteria. As the dredged materials over the expected at the design level were common and there are still lack of land based reclamation area, we have no choice to discharge the dredged materials in open sea area In this study, we analysed the behavior of discharged materials at the dumping area of offshore, which were collected from the dredging work at the waterway in Busan New Port. We measured the tidal currents and analyzed the waters of dumping site after the dumping work. These were used to evaluate the numerical models. Suspended Solids(SS) were introduced to the diffusion model. Because of the characteristic of the dumping site, the speed of initial diffusion and settle down of the discharged materials was so fast. Therefore, we believe that the dumped materials do not cause a significant impact to the marine environment.

• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 2014년도 춘계학술대회
• /
• pp.68-69
• /
• 2014

우리나라 관할해역까지 확장된 해상교통 모니터링이 필요하여, 장기적으로는 전 세계 원하는 해역의 선박 모니터링이 요구되는 시점이다. 이를 통해서만 우리의 Sea Line의 확보가 가능하며, 해양 경제영토의 확장이 가능하기 때문이다. 이와 같은 목표를 위한 초기 단계로, 경기만 연안 통합모니터링 시험을 거쳐 2013년 11월에는 이어도해양과학기지에서 실험이 이루어졌으며, 이 결과를 이번 학술대회에서 소개하고자 한다.

• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 2000년도 추계학술대회논문집
• /
• pp.95-107
• /
• 2000

The primary purpose of dredging work is to maintain navigational readiness and to increase environmental amenity, so that the dredging project which is composed of excavating, removing, transporting, storing and disposing dredged material must be carefully managed to insure that dredging works are completed in a cost-effective and environmentally safe manner. The most important point in dumping operations is an estimating and reducing the impacts of discharges at the dumping area. One of the most effective method for the reduction of ecological impacts at dumping area is using the schematic process composed of the sophisticated plan, precise work and predicting/reducing the impacts based on the numerical model and field observation. In this study, the numerical model is used to predict the near-field spatial fate and begavior of effluent discharged from Confined Dumping Facility(CDF) located near coastal area. To to this purpose, reappearing of tidal current was preceded. The model is then applied to Mokpo harbor, where capital dredging and maintenance dredging are conducted simultaneously and the CDF is under construction;. In the series of model case study, we found that the near-field behavior of effluent discharged from CDF was governed by the receiving water condition, outfall geometry, characteristics of efflent and CDF operating conditions.

• 무역상무연구
• /
• 제57권
• /
• pp.111-135
• /
• 2013

This study analyzes some important spin-off effects of the provision, UCP600 Article 14(6), through the methodology of the expected utility maximization theory based on the state-contingent commodities model. Some technical implications of this study are as follows. First, the risk-averse beneficiary will choose to present his documents more than 5 days before expiry date by paying a higher risk premium (so-called cure period) for full assurance to cure documentary discrepancies, if expressed economically, he pursues loss reducing activities to the point where the expected marginal product of his activities is less than its marginal cost. Secondly, where the effectiveness of securing cure period is uncertain, the risk-averse beneficiary will choose to present documents just on the expiry date without securing any cure period by paying no risk premium. This study finally suggests the safe harbor standard should be optimal solution only if it is supplemented by the hidden reasonableness standard for balancing the conflicts of interest between beneficiaries and banks.

• 무역상무연구
• /
• 제46권
• /
• pp.351-380
• /
• 2010

Multinational Enterprises set the prices for transactions between affiliates based principally on their global interest. But the customs authority in Korea wants to set the arm's length price as high as possible to get higher dutiable value for customs purpose, while the internal tax authority in Korea prefers lower arm's length price to get higher value for corporation tax purpose by cutting costs. Problem caused by the inconsistent valuation methods on the same imported goods of the two tax authorities is the single most important tax issue facing multinational enterprises. In the meantime, the customs authority in Korea has thought that it is a universal trend worldwide for the Customs and Internal tax authorities to adopt different methods of valuation on transfer prices between related parties, so KCS couldn't accept APA prices. But the internal tax authority in Korea has taken the initiative in APA program so NTS provided taxpayer with safe-harbor. Recently, KCS created the Advance Customs Valuation Arrangement(ACVA) provisions in the 2008 revision bill of the Customs Act through benchmarking APAs program. Can APAs work for customs? Neither WCO or OECD presents any recommendation on the integration of the valuation methods, but calls for close cooperation between two authorities, which still leaves taxpayers very unstable. We will start to seek ways to integrate the customs valuation and transfer pricing in this study.

• 한국항해항만학회지
• /
• 제33권9호
• /
• pp.609-614
• /
• 2009

The traffic of tug/barges which are carrying construction materials, large plants for harbor development, or offshore structures has recently increased in the coast of Korea. The west and south coast of Korea are always congested due to a lot of islands and traffic concentration. Specially tug/barges have higher probability of marine accidents due to their bad maneuverability than others. Considering the operational circumstance and maneuverability, this study was to develop a wide-area monitoring and control system for tug/barges in the coastal area of Korea. The system was made in the form of three program modules i.e. navigation analysis program module, monitoring and control program module, database module. And seven functions were programmed to monitor and control the tug/barges efficiently. These are ship information search, tug/barge information and track management, designated area and safe navigation zone management, fairway management, accident data management, warning of danger, safety information management.

• 한국항해항만학회지
• /
• 제41권5호
• /
• pp.345-352
• /
• 2017

Recently, a new port reserves deep water depth for safe navigation and mooring, following the trend of larger ship building. Larger port facilities include long and huge breakwaters, and mainly adopt vertical type considering low construction cost. A vertical breakwater creates stem waves combining inclined incident waves and reflected waves, and this causes maneuvering difficulty to the passing vessels, and erosion of shoreline with additional damages to berthing facilities. Thus, in this study, the researchers have investigated the response of stem waves at the vertical breakwater near the entrance channel and applied numerical models, which are commonly used for the analysis of wave response at the harbor design. The basic equation composing models here adopted both the linear parabolic approximation adding the nonlinear dispersion relationship and nonlinear parabolic approximation adding a linear dispersion relationship. To analyze the applicability of both models, the research compared the numerical results with the existing hydraulic model results. The gap of serial breakwaters and aligned angles caused more complicated stem wave generation and secondary stem wave was found through the breakwater gap. Those analyzed results should be applied to ship handling simulation studies at the approaching channels, along with the mooring test.

• 드라이브 ㆍ 컨트롤
• /
• 제11권3호
• /
• pp.7-13
• /
• 2014

Everyday about 90% of cargos are delivered by ships, and thousands of vessels enter and depart the international container harbors such as Shanghai, Singapore, Hong Kong, Busan, Rotterdam, etc. Maneuvering at harbor is known as the most sophisticated and difficult procedure, because the effectiveness of actuators during low speed berthing is reduced. In this paper, a new berthing method is discussed. Tugboats are combined with damper systems to ensure safe berthing. A mathematical model describing the interaction between unactuated ship, tugboats and damper systems is presented. An optimal controller is designed to maneuver the ship without oscillation and overshoot. MCL (Marine Cybernetics Lab) model ship is used to evaluate the efficiency of the proposed approach through MatLab simulation.