• International Journal of Naval Architecture and Ocean Engineering
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• 제13권1호
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• pp.306-320
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• 2021

To ensure safe port operations around the world, it is important to solve mooring problems. In particular, the many ports that face open seas have difficulties with long-period waves. As a countermeasure, the installation of a breakwater is proposed for mooring safety. However, this often cannot be put into practice because of financial issues. Instead, port terminals control berthing schedules with weather forecasting. However, mooring problems remain unsolved, because of inaccurate wave forecasting. To quantify the current situation, numerical simulations are presented with ship motions, fender deflections, and rope tensions. In addition, novel simulations for mooring ropes are proposed considering tension, friction, bending fatigue, and temperature. With this novel simulation, the optimal mooring method in terms of safety and economic efficiency was confirmed. In terms of safety, the optimal mooring method is verified to minimize dangerous mooring situations. Moreover, the optimal mooring method shows economic benefits and efficiency. It can help to reinforce the safety of port terminals and improve the efficiency of port operations.

• 대한조선학회논문집
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• 제60권6호
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• pp.433-440
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• 2023

This study aims to establish safety zones for bunkering operations of hydrogen propulsion ships in coastal areas through risk assessment and evaluate their validity. Using a 350 kW-class ferry operating in Busan Port as the subject of analysis, with quantitative risk assessment based on accident consequence and frequency analysis, along with a social risk assessment considering population density. The results of the risk assessment indicate that all scenarios were within acceptable risk criteria and ALARP region. The most critical accident scenarios involve complete hose rupture during bunkering, resulting in jet flames (Frequency: 2.76E-06, Fatalities: 9.81) and vapor cloud explosions (Frequency: 1.33E-08, Fatalities: 14.24). For the recommended safety zone criteria in the 6% hose cross-sectional area leakage scenario, It could be appropriate criteria considering overall risk level and safety zones criteria for hydrogen vehicle refueling stations. This research contributes to establishing safety zone for bunkering operations of hydrogen propulsion ships through risk assessment and provides valuable technical guidelines.

• 한국국방경영분석학회지
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• 제15권2호
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• pp.147-159
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• 1989

This paper presents a formalized methodology for conducting cost-effectiveness analysis on the ROK Navy's maritime patrol aircraft. The methodology involves a Delphi method application for determining the group of appraisal variables as well as their weight values in the area of aircraft effectiveness analysis, Life-cycle costing was employed to produce cost in terms of present worth values of all costs that occur over the common 20-year life cycle. A wide range of experts was selected so that their opinions could be effectively collected and synthesized to form the framework of the effectiveness model. Such a model development strategy provides easy acceptance of the analysis result and assure fairness of the analysis.

• International Journal of Ocean System Engineering
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• 제3권4호
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• pp.218-224
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• 2013

This paper describes the design and control of a hovering AUV test-bed and analyzes the dynamic performance of the vehicle using simulation programs. The main purpose of this vehicle is to carry out fundamental tests of its station keeping, attitude control, and desired position tracking. Its configuration is similar to the general appearance of an ROV for underwater operations, and its dimensions are $0.75m{\times}0.5m{\times}0.5m$. It has four 450-W thrusters for longitudinal/lateral/vertical propulsion and is equipped with a pressure sensor for measuring the water depth and a magnetic compass for measuring its heading angle. The navigation of the vehicle is controlled by an onboard Pentium III-class computer, which runs with the help of the Windows XP operating system. This provides an appropriate environment for developing the various algorithms needed for developing and advancing a hovering AUV.

• 해양환경안전학회지
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• 제4권2호
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• pp.35-42
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• 1998

Marine casuality causes not only loss of lives and ships, but also severs damages to marine environment and related economic activities such as fishing industry, sea farming, and tourist industry. Basically, the great effort should be made to prevent the occurrence of maritime accidents by any means. However, once accident has occurred, the salvage works should be done rapidly and properly based on theoretical and technical informations, which could minimize the risk during salvage operation and the overall damage from the maritime accidents. Generally, to calculate accurate hydrostatics of a stranded ship, a large amount of input data is needed. But, an availability and a reliability of input data cannot be guaranteed in most situations, and the adequate time required for preparing all input data is not allowed to perform the timely operations of salvage. In this paper, the development process of simple computer program for salvage operation using limited input data is introduced and its application example is presented. This program was developed to provide technical support for planning salvage operations in the grounding accident.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2009년도 공동학술대회
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• pp.149-150
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• 2009

The problem of vehicle routing problem(VRP) with pair operations of pick up and delivery are well-known in real applications in logistics networks, as in planning the routes for automatic guided vehicles(AGVs) in an automatic container terminal(ACT), warehouses or in some just-in-time services. This paper will present a formulation to modeling the problem mathematically which can be used to generate optimal routes of carried vehicles in the field to reduce the incurred cost of moving goods. This selected model could be used in (semi-)automatic short-term planning systems for vehicle fleet working in ACT, or in modern warehouses which the long list of requests is parted and sorted in preprocessing orders systems.

• International Journal of Computer Science & Network Security
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• 제23권1호
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• pp.64-70
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• 2023

Maritime transport is dominant in the overall volume of all international transportation. Existence and overcoming of problems, which cause pressure on shipping safety, remain actual and fully concern both maritime and inland transport. Increasing speed and cargo capacity of the ships along with the reduction of crew members lead to the automation of a growing number of work processes, which indicates the need to actively introduce appropriate measures in the security system of sea-going ships and commercial ports and to develop modern approaches to minimize negative events and incidents in the process of ship operation. Advantages in use of modern methods of monitoring the safety of ship operations, management of possible events and incidents, including investigation of accidents, first, aimed at prevention of negative occurrences and ways of prevention on this basis. Considering statistics on incidents increase, this work presents analysis of general ship accident rate, study of major accidental events growth annually, and investigation of causes of incidents, which most frequently occur in port waters and at open sea. A survey of current approaches to ensuring the safety of shipping by implementing effective tools, such as event and incident management, has been conducted.

• Journal of Advanced Marine Engineering and Technology
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• 제40권9호
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• pp.859-867
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• 2016

선박연료유는 운항비의 높은 비율을 차지하는 필수적인 요소이다. 그러므로 기준에 적합한 적정량의 연료유를 수급 받는 것은 운항손실을 예방하기 위해서도 중요한 작업이라 할 수 있다. 하지만 연료유 수급 시 발생되는 분쟁은 연료유 공급항을 중심으로 매년 지속적으로 발생되고 있으며, 선박소유자는 이러한 분쟁을 예방하고 효과적으로 대응하기 위하여 검정업체와의 계약을 통해 독립적 제3자인 선박연료유 검정인을 연료유 수급과정에 참여시켜 사실관계에 대한 증명서 발급을 요청한다. 하지만 현재 연료유 수급분쟁 발생 시 선박연료유 검정원의 지위와 역할이 명확하지 않아 효과적으로 대응하지 못하고 있다. 따라서 이 논문에서 과연 선박연료유 검정인이 가지는 법적지위 및 책임을 규명해보고 선박연료유 검정인이 수급분쟁에 있어서 실질적인 역할을 할 수 있는 대책에 대하여 논하고자 한다.

• 한국항해항만학회지
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• 제46권1호
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• pp.26-32
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• 2022

해상운송과 육상운송이 교차하는 항만은 국제교역을 위한 필수 산업기반시설로 국가경제에 대단히 중요한 기능을 갖는다. 항만이라는 공간과 물리적 인프라도 중요하지만, 항만 인프라를 효율적 관리운영도 그에 못지않게 중요하다. 정부는 항만관리운영의 효율성과 전문성을 강화하기 위해 항만공사제도를 도입하고 항만공사를 설립하였다. 항만공사제도는 항만자치를 본질로 하기 때문에 항만공사의 독립성과자율성은 항만관리운영에 있어 대단히 중요하다. 그럼에도 불구하고 항만공사의 운영에 정부에 지나치게 간섭하고 있어 항만공사의 기능이 제대로 발휘되지 못하고 있다. 항만 관련 법제도의 개선이 필요하다는 지적이 꾸준히 제기되고 있다. 이에 항만공사 종사자, 공무원, 항만기업, 시민단체 등을 대상으로 항만공사의 자율성 강화를 위해 개선되어야 할 법제도에 대한 인식을 조사하고 정책방안을 제언하였다.

• 해양환경안전학회지
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• 제29권6호
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• pp.628-638
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• 2023

자율운항선박 기술은 점차 발전하고 있다. 하지만 완전 자율운항선박이 등장하기 전까지는 원격운영센터에서 원격운영자가 제어하는 형태를 가지게 될 것이다. 그러나 현재 그들의 면허체계는 국내외적으로 정해지지 않았다. 역량이 검증되지 않은 원격운영자의 등장은 항행 안전에 위험이 될 것이다. 본 논문에서는 문헌 연구를 통해 원격운영자의 면허체계를 위해 고려해야 할 평가기준과 국내 해기사 면허체계 내에서 수립할 수 있는 방안을 모색하고 AHP를 활용하여 분석하였다. 그 결과 원격운영자의 면허체계를 위해서는 우선적으로 법률제정이 필요하고 선박직원법 제4조 해기사 면허의 직종에 원격운영자의 직종을 추가하는 방안이 가장 선호되었다. 이에 따라 원격운영센터의 조직구성도 기존 선박의 선교인적관리 조직과 유사하게 형성할 수 있을 것이다. 본 연구는 자율운항선박의 인적 관리 측면에서 원격운영자의 효율적인 양성과 항행 안전에 이바지할 수 있을 것이다.