• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.05a
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• pp.90-95
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• 2004

Ail of the world, unification and extension of market enlarged scale of international commerce. Thus, not only production but also circulation of goods is brought into relief and transportation of most freights is performed using container. Container vessels are equipped with marry kinds of securing equipments such as Lashing, twistlock. Lashing is installed mainly in container vessel for the container stack with more than 3 containers. Damage of containers often arise from irrelevant lashing arrangement and bring economical loss. Much time and cost is requested for the Calculation of forces on container and determination of lashing arrangement In this study, We developed lashing analysis simulator which performs calculation and presenst relevant lashing arrangement. It will provide more convenient and efficient environment for lashing analysis.

• Journal of the Society of Naval Architects of Korea
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• v.51 no.5
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• pp.362-368
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• 2014

Container vessel sizes have constantly increased over the past two decades. With increasing ship sizes and higher container loading capacities, the adoption of lashing bridges has also increased. Today's lashing bridge designs range from 1st tier to 3rd tier lashing bridges. Container securing program of the past which is based on two lashing rods and 1st tier lashing bridge has to be improved to be suitable for the present time. The equilibrium equations in this study are established to cover the application of 3~4 lashing rods and 2nd~3rd tier lashing bridges. In addition developed program is improved to be able to calculate the reaction forces and optimum arrangement under the external lashing. An optimization algorithm which is suitable for the container securing problems involved the equality constraint has been also adopted in this study.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.181-186
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• 2005

A ship runs with various modes of motion due to waves. Among the modes, roll mainly influences on the safety of cargos on the deck of container ship. In order to protect cargo shifting and turning, securing and lashing system are generally installed. In that case, it is necessary that the force and moment at the connection point of containers should be estimated. Therefore we derived mathematical equations to calculate the forces of securing points and lashing wires. Also we calculated those forces and moments about various lashing patterns.

• Journal of Navigation and Port Research
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• v.29 no.5 s.101
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• pp.377-382
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• 2005

A ship runs with various modes of motion due to waves. Among the modes, roll mainly influences on the safety of cargos on the deck of container ship. In order to protect cargo shifting and turning, securing and lashing system are generally installed. In that case, it is necessary that the force and moment at the connection point of containers should be estimated. Therefore we derived mathematical equations to calculate the forces of securing points and lashing wires. Also we calculated those forces and moments about various lashing patterns.

• Journal of Ocean Engineering and Technology
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• v.30 no.6
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• pp.451-457
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• 2016

For a carferry with a displacement of 1,633 tonf, a seakeeping analysis-based direct load approach (DLA) was used in Part I of these series, where the final deliverable was the long-term probabilistic acceleration components. In Part II of these series, the tangential acceleration components are explained based on two approaches: a standard called the IMO CSS code and simple formulas with the probable maximum roll and pitch rotations. The subsequent tangential acceleration-induced external force components are also introduced for these two approaches. The lashing strength components were selected from the IMO CSS code. It was assumed that two different vehicles (a car and a truck) were stowed at the most distant locations on the main deck to assume the largest tangential acceleration components and were secured with four steel wires with longitudinal and transverse lashing angles of $45^{\circ}$. Four cases were considered, with different methods for predicting the acceleration components and different tools for the external loads and lashing strengths involved: cases Rule-LS (rule-based maximum probable roll and pitch angles for predicting the acceleration components in conjunction with LashingSafety), DLA-LS (seakeeping-based long-term acceleration components with LashingSafety), CSS-LC (IMO CSS code-based acceleration components using LashCon), and CSS-LS (IMO CSS code-based acceleration components using LashingSafety). In terms of the acceleration and external force components, the CSS-LC and CSS-LS results are more than two times the results of Rule-LS. Thus, when the external forces and lashing strengths are evaluated using CSS-LC and CSS-LS, the truck needs more lashing wires, while Rule-LS and DLA-LS predict that the present lashing configuration is on the safe side.

• Journal of Navigation and Port Research
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• v.27 no.4
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• pp.397-402
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• 2003

Generally, container arrangement has been carried out based on the Classification guidelines. However, guidelines provide only container securing forces for the given container arrangement and Classification requirements of the forces. In order to design container arrangement additional information is needed such as container securing forces and arrangement that accounts for lashing bridges, vertical lashing, vertical center of gravity (VCG), and maximum stack weight. Trial and error method using the existing guidelines requires excessive amount of calculation time and cannot provide accurate results of the calculations. In order to fulfill this need, a new container securing system has been established based on the equilibrium conditions that include lashing bridges and vertical lashing. An optimization algorithm has been developed for the new system since current optimization methods such as genetic algorithms and evolution strategies are unsuitable for the container securing problems, which involve equality constraint. Design variables are container weights of tier and objective function is either total container weight or VCG of a stack. The newly developed system provides optimum arrangement of containers for both maximum stack weight and maximum VCG. It also greatly reduces time for designing container arrangement.

• Proceedings of the KWS Conference
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• 2009.11a
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• pp.6-6
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• 2009

자동차 운반용 선박(PCTC) 건조 시, 자동차를 고정시키기 위해 약 5 만 여개의 Lashing Socket(6,700 Units PCTC 기준)이 소요되는데, 이때 사용되는 Lashing Socket 은 용도 및 형태에 따라 Hole Cup, Flush Cloverleaf Type Pot, Raised Cloverleaf Type Pot, D-Ring, Crinkle Bar 등으로 구분된다. 이와 같이 다양한 종류 중에서 Hole cup 타입이 전체 적용되는 Lashing Socket 의 약 80%에 이른다. 기존에 사용되고 있는 자동용접장치는 Hole Cup 이외에는 적용이 불가능하고, 자석을 이용하여 Hole Cup 의 상부에 위치시키는 방식이었기 때문에 경량화 및 다양한 종류 및 크기의 Lashing Socket 에 적용이 가능한 자동용접장비의 개발이 요구되었다. 본 연구에서는 두께가 다른 $\phi$140 Hole Cup 및 Flush Cloverleaf Type Pot, Raised Cloverleaf Type Pot 에 적용 가능하며, 분리형 용접캐리지와 Centering Template, Magnet Jig 로 구성된 연속 및 단속 용접이 가능한 자동용접장치를 연구 개발하였다. 이를 통해 종래 Hole Cup 전용 자동용접 캐리지의 문제점을 개선하여, 작업자가 Centering Template 과 Magnetic Jig 을 이용하여 캐리지를 Hole Cup 의 중앙에 위치시키기 용이하게 하였다. 이 같은 분리형 장치 구성을 통해 Hole Cup 중앙에 캐리지 고정 작업과 용접 작업을 분리함으로써 자동용접이 진행되는 도중에 여분의 Jig를 이용하여 다른 Hole Cup 에 용접 준비를 하여 연속적인 작업이 가능하도록 하였다. 본 연구는 종래의 Hole Cup 전용 자동용접 캐리지의 문제점을 개선한 분리형 용접 캐리지를 개발함으로써 아래와 같은 결과를 얻었다. 1. 용접 캐리지를 포함하여 각 부분별 분리를 통해 작업자가 1 회 이동 시 필요로 하는 중량을 감소시켜 장비의 이동 및 제어가 쉽다. 2. Magnetic Jig 를 Centering Template 에 결합하고, Template 의 Jig 를 Lashing Socket 에 결합함으로써 손쉽게 Lashing Socket 의 중심부를 찾을 수 있으므로 용접 캐리지의 정확한 센터 고정이 가능하다. 3. 엔코더에 의한 1 회전을 검출함으로써, 작업 종료 후, 어떤 위치에서나 작업 재개가 가능하며 원점 복귀 작업이 불필요하다. 또한 엔코더에 의한 거리 설정으로 용접 속도에 상관없이 동일한 거리만큼 오버랩 용접이 가능하다. 4 디지털 방식으로 용접 조건의 입력이 가능하고, 용접 조건을 D/B 화 함으로써 Control Panel 상에서의 자동 제어가 가능하다. 이를 통해 연속 용접 또는 단속 용접이 가능하므로 다양한 형태의 Lashing Socket 을 자동 용접할 수 있는 효과가 있다. 이상의 결과를 통해 본 장비가 Fig.2 의 3 가지 종류의 Lashing Socket 용접에 효과적인 장비임을 확인할 수 있었다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.1
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• pp.1-7
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• 2020

In recent years, cargo lashing has received much importance, to help prevent the sinking of passenger ships due to the failure of vehicle and cargo lashing during the transshipment of cargo. Consequently, the standards for lashing equipment and the structure of car ferries have been revised. According to the current standards, all vehicles loaded on a car ferry sailing in smooth sea areas must be secured if the wind speed and wave height exceed 7 m/s and 1.5 m, respectively. In this study, we measured the roll and pitch of a passenger ship sailing in smooth sea areas, and compared the measurements with the results of the New Strip Method (NSM). The vessel had a maximum pitch of 1.41° and a maximum roll of 1.37° at a wind speed of 6-8 m/s and a wave height of 0.5-1.0 m, and a maximum pitch of 1.49° and a maximum roll of 2.43° at a wind speed of 10-12 m/s and a wave height of 1.0-1.5 m. A comparison of the external forces due to the motion of the hull and the bearing capacity without lashing indicated that the bearing capacity was stronger. This suggests that vehicles without lashing will not slip or fall due to weather conditions. In future, the existing vehicle lashing standards can be revised after measuring the hull motions of various ships, and comparing the external force and bearing capacity, to establish more reasonable requirements.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.591-592
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• 2013

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.2
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• pp.230-237
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• 2023

Due to the COVID-19 pandemic and climate change, shortages of essential commodities and resources continue to occur globally. To address this problem, trade volume demand suddenly increased, driving up the freight rate of container ships sharply. The size of container vessels progressively increased from 1,500 TEU (twenty-foot equivalent unit) in the 1960s to 24,400 TEU in 2021. As the improvement of container loading capacity is closely related to the enlargement of the lashing bridge structure, it is necessary to design a structure effective for good container securing and safe under the various external loads that occur during voyage. Major classification societies have recently issued structural-analysis-based guidelines to evaluate the structural safety of lashing bridges, but their acceptance criteria and evaluation methods are different, causing confusion among engineers during design. In this study, the strength change characteristics are summarized by variations in the main variables (modeling range, opening consideration, mesh size) likely to affect the results. Based on this result, the authors propose a reasonable structural-analysis-based evaluation that is expected to serve as a reference in the next revision of classification standards.