• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.12
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• pp.1265-1273
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• 2015

A coal handling machine is a type of equipment used for loading coal, the main material in a steam power plant, along a conveyer belt from a ship, and is placed after the driving chain bucket. However, studies on the boom hoisting cylinder, which is a hydraulic system used to control the angle of the boom based on loading location, indicate that domestic models are insufficient, and are thereby often substituted with a foreign product. In this study, a technique for analyzing the contact pressure in a thick-walled cylinder was established by comparing the contact pressure, which is calculated theoretically based on the results obtained from FEM simulation, and by checking whether the working oil is leaking from the boom hoisting cylinder using a v-seal. In addition, the driving motion was simulated according to the strokes of the cylinder, and the structural stability was verified under the maximum output conditions.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2525-2528
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• 2003

본 논문은 제철소 원료공장에서 선박으로부터 철광석, 석탄 등의 원료를 언로다 내부의 벨트 컨베이어로 이송 시, 선박과 부두와의 공간이 발생하여 이 공간으로 원료가 낙광 하여 해양오염이 발생하고 원료의 유실 등의 문제점을 해결하기 위한 낙광방지 시스템 개발에 관한 연구이다. 초음파 센서를 이용한 선박과의 거리 인식 및 PLC 제어기를 이용한 자동 제어 방법을 제시한다. 언로다 본체에 낙광방지판과 이를 구동하는 에어 실린더형태의 구동기와 낙광방지판을 연결하는 링크부로 구성되는 시스템에 있어서, 거리 감지 센서 3대로부터 선박과의 최소 거리를 구하고 이를 PLC 제어기를 이용하여 목표 거리와의 오차를 구한 다음, 오차의 증감에 따라 구동기인 에어 실린더의 이동량을 구하여 낙광방지판을 선박과 최대한 밀착시켜 하역 작업을 하고, 떨어진 낙광을 자동으로 회수하는 시스템에 관한 논문이다.

• Proceedings of the KIEE Conference
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• 2003.11b
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• pp.304-306
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• 2003

본 논문은 제철소 원료공장에서 선박으로부터 철광석, 석탄 등의 원료를 언로다 내부의 벨트 컨베이어로 이송 시, 선박과 부두와의 공간이 발생하여 이 공간으로 원료가 낙광 하여 해양오염이 발생하고 원료의 유실 등의 문제점을 해결하기 위한 낙광방지 시스템 개발에 관한 연구이다. 초음파 센서를 이용한 선박과의 거리인식 및 PLC제어기를 이용한 자동 제어 방법을 제시한다. 언로다 본체에 낙광방지판과 이를 구동하는 에어실린더형태의 구동기와 낙광방지판을 연결하는 링크부로 구성되는 시스템에 있어서, 거리 감지 센서 3 대로부터 선박과의 최소 거리를 구하고 이를 PLC 제어기를 이용하여 목표 거리와의 오차를 구한 다음, 오차의 증감에 따라 구동기인 에어 실린더의 이동량을 구하여 낙광방지판을 선박과 최대한 밀착시켜 하역 작업을 하고, 떨어진 낙광을 자동으로 회수하는 시스템에 관한 논문이다.

• Journal of Korean Society for Quality Management
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• v.51 no.2
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• pp.315-327
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• 2023

Purpose: Recently, research has continued to predict the time of failure of the facility through measurement data obtained by attaching a sensor to the facility. However, depending on the facility, it may be difficult to attach a sensor. The purpose of this study is to propose a power generation maintenance plan system based on failure record data obtained from Continuous Ship Unloader, one of the facilities that is difficult to attach sensors. Methods: This study uses data collected from 2012 to 2022 from the 'CSU-1B' model among Continuous Ship Unloader operated by Korea Midland Power Co., LTD. By fitting fault record data to the Weibull distribution, appropriate maintenance cycles and ranges for each target facility subsystem are derived. In addition, maintenance group between subsystems is selected through Euclidean distance, a metric often used for time series data similarity. Through this, a system for establishing an maintenance plan for power generation facilities is proposed. Results: The results of this study are as follows. For the 17 subsystems of the Continuous Ship Unloader, proper maintenance cycles and ranges were determined, and a total of four maintenance groups were chosen. This resulted in the creation of an power generation maintenance plan system and the establishment of an maintenance plan. Conclusion: This study is a case study of power generation facilities. We proposed a maintenance plan system for Continuous Ship Unloader among power generation facilities.

• Journal of Korea Port Economic Association
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• v.37 no.4
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• pp.161-173
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• 2021

The shipping industry plummeted and was depressed due to the global economic crisis caused by the bankruptcy of Lehman Brothers in the US in 2008. In 2020, the shipping market also suffered from a collapse in the unstable global economic situation due to the COVID-19 pandemic, but unexpectedly, it changed to an upward trend from the end of 2020, and in 2021, it exceeded the market of the boom period of 2008. According to the Clarksons report published in May 2021, the decrease in cargo volume due to the COVID-19 pandemic in 2020 has returned to the pre-corona level by the end of 2020, and the tramper bulk carrier capacity of 103~104% of the Panamax has been in the ports due to congestion. Earnings across the bulker segments have risen to ten-year highs in recent months. In this study, as factors affecting BDI, the capacity and congestion ratio of Cape and Panamax ships on the supply side, iron ore and coal seaborne tonnge on the demand side and Granger causality test, IRF(Impulse Response Function) and FEVD(Forecast Error Variance Decomposition) were performed using VAR model to analyze the impact on BDI by congestion caused by strengthen quarantine at the port due to the COVID-19 pandemic and the loading and discharging operation delay due to the infection of the stevedore, etc and to predict the shipping market after the pandemic. As a result of the Granger causality test of variables and BDI using time series data from January 2016 to July 2021, causality was found in the Fleet and Congestion variables, and as a result of the Impulse Response Function, Congestion variable was found to have significant at both upper and lower limit of the confidence interval. As a result of the Forecast Error Variance Decomposition, Congestion variable showed an explanatory power upto 25% for the change in BDI. If the congestion in ports decreases after With Corona, it is expected that there is down-risk in the shipping market. The COVID-19 pandemic occurred not from economic factors but from an ecological factor by the pandemic is different from the past economic crisis. It is necessary to analyze from a different point of view than the past economic crisis. This study has meaningful to analyze the causality and explanatory power of Congestion factor by pandemic.