• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.3
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• pp.341-346
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• 2008

This paper is to develop a monitoring system with diagnosis for smart cargo sensors that is for management and maintenance of the liquid cargo ships. The main goal of the system is to achieve the total automation system of the cargo sensor. By this study, the active smart sensor for the liquid cargo ships is designed and developed that guarantees high-confidence, stability, and durability. The proposed system consists of a monitoring part of the steam pressure, high-level monitoring, over flowing monitoring, gas monitoring, and tank temperature monitoring. The signals transferred from each unit system are used for sensor diagnosis based on confidence and accuracy. Finally, in this study, the total supervisory monitoring system is developed to maintain and manage the cargo effectively based on fault diagnosis and prognosis of the each sensor system.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.11a
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• pp.169-173
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• 2000

현재 컨테이너 터미널에서 사용되고 있는 하역 장비들은 크게 하역작업을 수행하는 크레인과 컨테이너를 운반하는 트레일러, 컨테이너의 하역상태를 파악하는 모니터링 시스템으로 구분할 수 있다. 각각의 장비들은 수동으로 동작되며, 모니터링 시스템에서는 컨테이너의 위치 및 수량 등을 파악한다. 이런 시스템 하에서는 모든 항만 하역 장비들을 사람이 일일이 수동으로 조작함으로써 많은 인력이 필요하다. 또한, 각 하역장비들의 상태를 평면적인 2차원 화면으로만 보여주므로써 모니터링 시스템에 대한 현실감이 떨어진다. 이와 같은 단점을 보완하기 위해 컨테이너를 자동으로 운반하는 AGV를 도입하고 트랜스퍼 크래인과 컨테이너 크레인의 일부분을 자동화하여 작업능률을 향상시키고, 여기에 3차원으로 표현된 VR 시스템을 도입하여 각 하역장비들에 대한 세세한 동작까지를 모니터링함으로써 사용자가 현장에 있는 것과 유사한 느낌을 가질 수 있도록 하였다. 본 논문에서는 이러한 3차원 VR시스템과 모형으로 만들어진 AGV와 컨테이너 크레인, 트랜스퍼 크레인간의 유기적인 데이터 송,수신 및 안정적인 통신을 위해 데이터 포맷에 대한 연구를 하였다. 이런 데이터 포맷의 결정은 손실 없는 통신을 보장하며 나아가 정확한 모니터링을 보장할 것이다.

• Bulletin of the Society of Naval Architects of Korea
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• v.56 no.2
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• pp.45-49
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• 2019

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.163-168
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• 2001

A FEM-based analytical approach was used to evaluate the fatigue strength of a KHST gangway. A KHST gangway was made of AC4C, 5083-O, 6005A-T6 aluminum alloys. The fatigue strengths of them were obtained from the related code and literatures. The effect of tensile mean stress was taken into account by the modified Goodman diagram, but the effect of compressive mean stress was not considered. There was not any location of a KHST gangway that exceeded the allowable fatigue strengths.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.958-960
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• 2015

Sickle cells possess a unique combination of traits that may enable their use as models for novel synthetic tumor targeting controlled release drug carriers with the ability to treat disseminated tumors in advanced metastatic disease. In this study, we assess the ability of light-activated release sickle cells to enhance tumor delivery of the fluorescent dye calcein by delayed photolysis controlled release compared to free systemic administration of calcein. Sickle cells from mouse models of the disease were shown to preferentially accumulate in tumors compared to adjacent tissue, in 4T1 tumors in mice on a time scale about 12 hours. Sickle cells photosensitized with protoporphyrin IX achieved delayed release of 50% of contents 8-16 hours after photoactivation, which was deemed useful for in vivo delivery of cargo to tumors given the tumor accumulation time of the sickle cells. Sickle cells may be useful as a model for new synthetic drug carrier particles with delayed photolysis controlled release properties.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.4
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• pp.444-449
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• 2020

In this study, On-Board Truck Scale was installed on the construction waste collection / transportation vehicles to monitor the weight of the waste at all stages from generation to final treatment. It was performed as a case study of a construction waste control technology that can efficiently manage the total generating and recycling amount using real-time weight/location information obtained by the On-Board Truck Scale device. As a result of the study, it was confirmed that the total amount of construction waste can be monitored in real time, and a plan for efficient logistics transportation can be derived through the analysis of operation patterns by managing the real-time transport volume, transport distance, and transport time of the construction waste collection / transportation vehicles. It was confirmed that overloading can be prevented in advance by controlling the loading also.

• Tribology and Lubricants
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• v.1 no.1
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• pp.46-58
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• 1985

The basic mechanism of lubrication between the piston ring and the cylinder wall is developed theoretically under the assumption of a reciprocating and dynamically loaded slider-bearing pair of parabolic form and smooth plane. A numerical computation for the prediction in cyclic variations of film thickness, net lubricant flow and frictional behaviour is attempted, and the influenec on the performance characteristics due to the ring height, ring face radius of curvature and the degree of offset, is also examined. The computational procedures develeped for a single ring system are extended and applied further to the complex problem of a ring pack system. It is well known that the ring pressure which is the total load on a ring, can be obtained from either an experimental measurement or a gas flow analysis. In this work, the latter of a gas low analysis method was used to calculate the pressures. It is remarked that the work done was focused on the role of flow continuity and lubricant starvation within the ring pack lubrication.

• Proceedings of the Korea Society for Simulation Conference
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• 1999.10a
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• pp.100-107
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• 1999

무인 운반차량 시스템 (AGV System) 의 이용도가 날로 증가함에 따라 시스템의 최적화 및 운영 방법에 관한 많은 연구가 진행되고 있다. 이에 본 연구에서는 AGV System에서 사용하는 Routing 및 Scheduling 정책들을 연구하고 이를 개선할 수 있는 새로운 방안을 모색한 후, 컴퓨터 모델링 기법을 이용한 보다 객관적인 시뮬레이션을 수행하여 최적의 AGV System과 그에 적합한 운영 정책을 제시하는데 그 목적이 있다. 따라서 본 논문은 크게 AGV Routing 과 Scheduling에 관한 연구로 나누어진다. AGV Routing은 AGV의 이동경로를 설정하는 것으로서 충돌 방지 (Collision Avoidance)와 최단경로 탐색 (Minimal Cost Path Find) 이라는 두 개의 주요 알고리즘으로 이루어진다. AGV Scheduling 은 장비의 공정시간과 AGV의 Loading/Unloading, Charging 시간으로 인해 불규칙한 Event 가 일어났을 경우 AGV 각각의 Jop을 알맞게 선정해주는 정책을 말하며 일반적으로 AGV Selection Rule, Charging Rule이 여기에 속한다. 본 연구에서는 이러한 알고리즘들이 반영된 AGV System을 컴퓨터 모델로 구축하여, 기존 시스템에서 사용되고 있는 여러 운영 정책들의 문제점들을 분석하였으며, Multiple AGV System을 최적화 시키는 운영 정책이 보다 객관적으로 제시되었다.

• Journal of the Korean Institute of Gas
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• v.21 no.1
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• pp.65-71
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• 2017

LNG is being spotlighted as a clean marine fuel because of recent trend in reinforcement of marine environmental regulation. In this paper, demand prospect of LNG bunkering for Ulsan port is carried out to analgize the possibility of commercialization of floating LNG bunkering terminal. Environmental analysis for LNG bunkering and LNG bunkering trends of competitive ports in the world are considered to draw out the prospection of LNG bunkering demand in Ulsan. As a result, car carrie and oil carrier were expected to have more possibility in switching to LNG fuelled ship. The LNG bunkering demand in Ulsan. As a result, car carrier and oil carrier were expected to have more possibility in switching to LNG fuelled ship. The LNG bunkering demand in Ulsan port was expected to be about from 650,000 ton to 900,000 ton in 2030 and Ulsan port is prospected to be a good port for FLBT business in th future.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.4
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• pp.529-537
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• 2021

Membrane-type hull and cargo holds have been designed and built for large ship. However, there is a growing interest in applying the same technology to small and medium-sized Liquefied natural gas(LNG) carriers to meet the recent increase in demand for LNG as an ecofriendly fuel and for expanding LNG bunkering infrastructure. The purpose of this study is to apply the IMO Type-B tank to small and medium-sized LNG carriers and verify the safety and suitability of the design. Fatigue crack propagation analysis was performed to install a partial second drip tray installed at the lower part of the LNG cargo tank by calculating the amount of leaked gas in the support structure supporting the cargo tank. First, a program for fatigue crack propagation analysis was developed, in which Paris' law and British Standard 7910 (BS 79110) were applied based on the International Code for the Construction of Equipment and Ships Carrying Liquefied Gases in Bulk, an international standard for LNG carriers. In addition, a surface crack propagation analysis was performed. Next, a methodology for assuming the initial through-crack size was developed to determine the size of the partial second barrier. The analysis was performed for 15 days, which is a possible return time after cracks are detected. Finally, the safety and suitability of the IMO Type-B for LNG cargo tanks required by international regulations were verified. For the accurate analysis of fatigue crack propagation, it is necessary to develop and verify the analysis procedure based on direct analysis and international regulations.