• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.06a
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• pp.344-346
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• 2012

대산항 씨텍 제3번 돌핀부두에 최초 설계의 접안능력기준을 약간 상회하는 5만 DWT급 VLGC 선박이 접안작업을 할 경우, 돌핀의 용량에 따른 접안작업 동안의 안전성 여부를 대산항만의 입출항 제한 자연 환경조건을 적용하여 선박 계류측면에서의 안전성을 판단하고자 한다. 이를 위하여 대상선박의 부두에서의 최악의 외력조건과 계류장력과의 관계를 OCIMF에서 연구 발표한 결과를 바탕으로 계류안전성 계산공식을 적용하여 계류안전성을 평가하도록 한다.

• Journal of Navigation and Port Research
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• v.43 no.1
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• pp.9-15
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• 2019

Mooring bollards are the mandatory facility in ports for they are the objects used to fasten the ship to its position at the berth. All the mooring bollards were installed following suggested sizes, numbers, materials and shape of installation according to Port and Fishing Design Standards. However, Korea has no management standard for use of mooring bollards to safety in ship berthing. In this research, the installation standard for mooring bollards including the holding power applied to mooring bollards in berthing was studied. Also, the performance of mooring bollards for minimum safety guarantee in berthing based on research of various specification by their sizes was analyzed. The analysis on mooring bollards was examined by each power on mooring bollards from the applied force in berthing divided into horizontal and vertical direction in order to examine the performance of domestic mooring bollards, the limit force is calculated based on detailed specification research result. As a result, the working stress according to the towing force was found to be at least 150Mpa and it was evaluated to be 60% of the limit strength. Also, by comparing each forces, the appropriateness was examined and the specification of maximum capability calculated. This performance evaluation method based on detail specification of mooring bollards will be expected to be useful to examine the appropriateness of mooring bollards for various types of vessel in berthing and to develop maintenance and management standard through the performance change evaluation referring to mooring bollard detailed specification changes.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2010.10a
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• pp.94-99
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• 2010

광양제철소의 광양만 제품부두에 접안하여 양하역 할 대상선박에 대해 여러 가지 해상조건에 대해 계류해석을 수행하였으며, 이를 통해 광양만 부두에서의 계류 적정선박을 선정하기 위한 기준 설정의 기초자료를 만들기 위해 노력하였다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.06a
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• pp.47-49
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• 2013

항만 확장 시 기존의 매립 방식은 건설비용 및 환경 파괴 등의 문제가 발생함으로써, 부유체식 구조물을 이용한 해상 부두의 활용이 국내외에서 주목받고 있다. 이와 관련하여 본 연구에서는 선박의 계류안전성평가에 대한 개념을 정립하고 이를 부유체식 Container Yard에 적용하기 위한 자연환경, 선박 및 부두 모델링을 수행하였다. 본 연구 자료를 토대로 향후 부유체식 Container Yard에 접안한 선박의 환경외력 및 계류삭의 장력 평가, 방충재와 계선주에 작용하는 반력 및 견인력 평가, 부두의 운동에 따른 안전성을 파악하고, 해상 부두로서의 적용 가능성을 검토하여 안전한 부두의 설계 기준 및 활용 방안을 마련하고자 한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2017.11a
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• pp.121-123
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• 2017

계선주는 선박이 접안 중 안전성을 확보하는 설비로서 계류안전성 평가에 필수 설비 중 하나이다. 이러한 계선주는 국내 항만 및 어항설계 기준의 견인력에 따라 규격이 구분되어 설치되나 규격별 성능 확인을 위한 평가 방법이 제시되지 않아 평가 방법 검토가 필요하다. 이 연구에서는 견인력에 따라 설치되는 계선주 규격별 제원을 분석하여 재질과 특성에 따라 견인력에 따라 작용하는 수평력과 수직력을 휨 응력과 전단 응력으로 나누어 분석하고 이에 따른 성능 적정성을 평가하고 살제 허용 견인력을 평가 하고자 하였다. 또한 계선주 설치 후 노후화로 인한 성능 변경을 평가하고 예측하고자 두께를 통한 평가 방안을 검토하고자 하였다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.1
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• pp.57-62
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• 2009

In order to investigate the hydrodynamic interaction between the tug-barge and bank or ship which is crossing to the opposite direction, the towing simulations of tug-barge transportation were performed. Heading of barge, yaw moment and lateral force of tug boat were obtained by this simulation. The characteristics of results were analyzed and the safety towing method for tug-barge operation was proposed. In order to reduce the slewing motion of barge for safe towing operation, the speed of tug boat should be kept slow ahead state with shortened towing line as length of barge within the limits of the possible.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.1
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• pp.107-116
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• 2022

Local management trade ports are small-sized trade ports, which require active operation to strengthen the local cities' economic power and enhance the local industries' added value. In addition, local management trade ports should berth ships larger than the existing ships to increase efficiency and keep up with the international trend where ships are becoming larger. Furthermore, they should also prepare operating standards. This study selected Okgye Port among local management trade ports. We performed a mooring safety simulation evaluation according to the scenario where a 50,000 DWT vessel is moored at the current 20,000 DWT class pier. The emergency departure criteria were 27kts at 3.2s of wave period and 22kts at 5.0s of wave period at the existing pier. Results showed that mooring limit condition increased by about 50% to 41kts at 3.2s of wave period and 36kts at 5.0s of wave period. This study can be used for strengthening mooring facilities and setting operational standards for safe port operation when large ships are berthing.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.11a
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• pp.233-235
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• 2022

43차 산업혁명이 도래함에 따라 해운분야에도 자동화 및 무인화 기술을 접목한 안정성과 효율성을 향상시키기 위한 기술개발이 진행중이다. 그중 선박의 신속하고 안전한 이/접안을 돕도록 고안된 자동계류시스템은 선박의 식별 정보와 융합센서로부터 다양한 정보를 수집해 인력의 개입이 최소화하거나 무인화할 수 있으며, 이는 계류 라인을 이용한 기존 방법 대비 발생하는 위험 요소를 줄이고 효율적인 도선 지원이 가능하게 한다. 본 연구팀은 기초단계 연구로서 자율 운항 선박 구현을 위한 자동 계류 시스템 개념 설계를 제시한다. 연구내용은 크게 자동 계류시스템의 하드웨어 설계, 제어 및 운용 프로세스 설계, 선체 계측 기술 개발, 운동변위/계류력 산정 수치모델 개발, 항만 내 운영환경 및 시나리오 분석으로 분류할 수 있으며 본 발표에서는 연구현황과 추후 진행 방향에 대해 다루도록 한다.

• Journal of Korean Ophthalmic Optics Society
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• v.15 no.3
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• pp.247-255
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• 2010

Purpose: Developing a roofed Pechan prism type scope with long eye relief. Methods: To reduce the overall length and to lengthen the eye relief of scope, the objective part was designed by adopting the roofed Pechan prism and also the eyepiece part was designed by adopting the field lens with minus refractive power in front of reticle, respectively. Finally, by integrating above two parts, the roofed Pechan prism type scope with 90 mm eye relief was developed. Results: The characteristics of the developed and fabricated scope with 90 mm eye relief by integrating the objective part with the roofed Pechan prism and the eyepiece part with minus refractive power had the magnification of $+3.0{\times}$, the length from the 1st lens to the last lens of about 121 mm, the barrel diameter of 28 mm, and the effective objective-diameter of 17 mm. Also it was found that the line width of resolution was about 900 cycles/rad at the 50% MTF value criterion. Conclusions: We could design and manufacture the roofed Pechan prism type scope with 90 mm eye relief, the characteristics of which had the magnification of $3.0{\times}$, the MTF above 50% at 900 cycles/rad, and the length from the 1st lens to the last lens of about 121 mm.

• Journal of Navigation and Port Research
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• v.41 no.3
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• pp.137-148
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• 2017

Port service level is a metric of competitiveness among ports for the operating/managing bodies such as the terminal operation company (TOC), Port Authority, or the government, and is used as an important indicator for shipping companies and freight haulers when selecting a port. Considering the importance of metrics, we developed software to objectively define and manage six important service indicators exclusive to container and bulk terminals including: berth occupancy rate, ship's waiting ratio, berth throughput, number of berths, average number of vessels waiting, and average waiting time. We computed the six service indicators utilizing berth 1 through berth 5 in the container terminals and berth 1 through berth 4 in the bulk terminals. The software model allows easy computation of expected ship's waiting ratio over berth occupancy rate, berth throughput, counts of berth, average number of vessels waiting and average waiting time. Further, the software allows prediction of yearly throughput by utilizing a ship's waiting ratio and other productivity indicators and making calculations based on arrival patterns of ship traffic. As a result, a TOC is able to make strategic decisions on the trade-offs in the optimal operating level of the facility with better predictors of the service factors (ship's waiting ratio) and productivity factors (yearly throughput). Successful implementation of the software would attract more shipping companies and shippers and maximize TOC profits.