• Journal of the Korea Concrete Institute
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• v.22 no.4
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• pp.535-546
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• 2010

Recently, the probability of collision accident between vehicles or vessels and infrastructures are increasing at alarming rate. Particularly, collision impact load can be detrimental to sub-structures such as piers and columns. The damaged pier from an impact load of a vehicle or a vessel can lead to member damages, which make the member more vulnerable to impact load due to other accidents which. In extreme case, may cause structural collapse. Therefore, in this study, the vehicle impact load on concrete compression member was considered to assess the quantitative design resistance capacity to improve, the existing design method and to setup the new damage assessment method. The case study was carried out using the LS-DYNA, an explicit finite element analysis program. The parameters for the case study were cross-section variation of pier, impact load angle, permanent axial load and axial load ratio, concrete strength, longitudinal and lateral rebar ratios, and slenderness ratio. Using the analysis results, the performance based resistance capacity evaluation method for impact load using satisfaction curve was developed using Bayesian probabilistic method, which can be applied to reinforced concrete column design for impact loads.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2023.05a
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• pp.210-211
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• 2023

To reduce maritime accidents and improve safety for domestic ships, the government has developed and is operating the Korean e-Navigation Service. The ship collision and grounding monitoring service and the route planning service were developed based on the experience of captains and navigators who navigated large ships. However, in Korea, small ships account for a large portion of the users of these services, so there are various difficulties and additional requirements for applying services based on large ships to small ships. To improve this, a data science-based algorithm model using maritime digital traffic information is being developed for small ships, and it is important to evaluate the performance of the developed model and compare its accuracy with existing services. In this study, we propose a performance evaluation method for the developed algorithm model and study how to compare and evaluate its accuracy with existing e-navigation services.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.10a
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• pp.745-748
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• 2001

Digital-ship is the next-generation ship with an one-man bridge system which consists of INS(Intelligent Navigation System), AIS(Automatic Identification System), and IMIT(Integrated Maritime Information Technology). INS implements the functions is related of the ship's navigation, and supports in the digital GIS environments optimal route planning, stranding and a collision avoidance among the ship, an economic navigation, and an integrated control of ship's engine. AIS prevents the ship's collision by means of transmitting periodically the own ship's information to the other ship or the shore control center. IMIT systems supports the integrated fiat-form in ships, the communication between a ship and a control center of the land using the INMARSAT, OrbComm, Ocean Observation Satellite, and etc. The satellite communication in ships can monitor the ship at an earth control renter. This paper deals with the method for system implementation of digital-ship and the detailed sub-system.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2020.11a
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• pp.39-41
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• 2020

충돌 회피를 위한 위험도 평가에서 CPA 계산은 핵심 요소이며, AIS의 도입 이후 AIS 정보를 이용한 CPA 계산이 필수적으로 활용되고 있다. 본 논문에서는 CPA 계산에 이용되는 AIS 정보와 실제 특성을 확인하고, 선박 위치 추정에 관련된 선행 연구들을 분석하며, 이를 가상 디지털 항로 표지 서비스에 적용할 방안을 강구한다, P. Last 등의 연구는 ROT의 중요성을 강조하고 있으나, 대부분의 선박이 필요로 하는 정확한 ROT 값을 전송하지 못하고 있는 상황을 확인했고, Ling-Zhi Sang 등의 연구는 4가지 요소를 반영한 간단한 식으로 구현하여 전 해역의 데이터로 비교한 결과 2가지 요소만을 적용한 방법에 대한 정확도의 향상을 확인할 수 없었다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.336-338
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• 2018

대부분의 해양사고는 인적요인에 의한 과실이 대다수이며 이 문제를 해결하기 위해 해양수산부는 국제 e-Navigation의 주도를 위해 한국형 이네비게이션 사업단을 선정하여 연구과제를 수행 중에 있다. 이네비 연구과제의 사고 취약선박 모니터링 지원 서비스는 선박, 해역, 환경의 취약상황을 반영한 항해 위험도를 산출하는 알고리즘을 개발하고 있으며 충돌 알고리즘 산출을 위해 다양한 종류의 데이터를 수집 및 분석을 수행하고 있다. 이 연구는 이력 기반 취약성 평가를 위한 해상 통계데이터 수집 및 그 데이터의 활용 방안을 수립하고, 데이터 분석결과를 보인다.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2009.06a
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• pp.399-400
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• 2009

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2010.10a
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• pp.16-18
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• 2010

현재 우리나라에서 해상 수송은 무역 수 출입의 90%이상을 담당하고 있으며, 지정학적인 측면에서도 많은 중요한 역할을 하고 있다. 해상에서의 교통시스템 기능이 안정적으로 유지되고, 더욱 발전되기 위해서 무엇보다 연안 해역에서의 선박 교통에 대한 정확한 이해가 필요하다. 본 논문에서는 선박별 항적과 같은 선박 교통의 자료들을 기초로 하여, 우리나라의 각 수역별로 선박 흐름을 재현해 보는 연구를 수행하였다. 구체적으로 선박종류 항로특성 실제교통량 등을 해상 교통의 구성요소별로 분류하고, 자동피항 기능을 포함한 다수 선박간의 흐름을 재현하는 프로그램을 개발하였다. 개발된 프로그램은 목포항의 선박교통 자료를 기본으로 시뮬레이션을 실시하여 검증하였다. 또한 개발된 모델을 수역의 교통안전성 예측, 항로내 시설물 설치시 적정성 문제 등에 적용가능한 지를 고려하였다.

• Journal of Navigation and Port Research
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• v.47 no.6
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• pp.401-409
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• 2023

This study compared and analyzed the performance of a distributed area search algorithm and a distributed probability search algorithm based on information exchange between ships. The distributed algorithm is a method that can search for an optimal avoidance route based on information exchange between ships. In the distributed area search algorithm, only a ship with the maximum cost reduction among neighboring ships has priority, so the next expected location can be changed. The distributed stochastic search algorithm allows a non-optimal value to be searched with a certain probability so that a new value can be searched. A circular-based ship collision avoidance model was used for the ship-to-ship collision avoidance experiment. The experimental method simulated the distributed area search algorithm and the distributed stochastic search algorithm while increasing the number of ships from 2 to 50 that were the same distance from the center of the circle. The calculation time required for each algorithm, sailing distance, and number of message exchanges were compared and analyzed. As a result of the experiment, the DSSA(Distributed Stochastic Search Algorithm) recorded a 25%calculation time, 88% navigation distance, and 84% of number of message exchange rate compared to DLSA.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.165-166
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• 2010

Collision scenario was 12 cases considering gate location, water level and lateral location of collision etc. And then, analysis result of trunnion by collision loads (reservoir side gate). Compressive fracture may not occur because the maximum compressive stress of concrete is below the allowable compressive strength. but, it is possible to appear some local crack because the maximum tensile stress exceed the tensile strength.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.6
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• pp.594-600
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• 2020

The identification of the risk of collision between ships and objects is vital for achieving navigation safety. The purpose of this study is to analyze the phenomenon of ship domain invasion by breakwaters when ships pass between breakwaters. A method for evaluating the domain-invaded area under the conditions of the breakwater was developed. Next, experimental data were obtained and processed using the Automatic Identification System (AIS) of ships sailing near the breakwater at Busan Port to establish a ship domain that could be formed between the breakwaters. The ship domain was then constructed using Fujii's domain. Finally, the phenomenon in which the constructed ship domain was invaded by the breakwater was analyzed. Based on the experimental results, the domain of the ship invaded by the breakwater was identified.