• Journal of Korea Port Economic Association
• /
• v.39 no.1
• /
• pp.47-63
• /
• 2023

In smart ports and port automation, the number of vertically deployed container terminals is growing. The purpose of this study is to analyze the productivity of horizontally arranged and vertically arranged container terminals by comparing the main ship operation time, and to recommend future strategies for increasing the operational efficiency of vertically configured container terminals. To achieve our goal, we chose two terminals representating each type, and collected berth allocation status data from 2018 to 2022. Then we analyzed the data using the Accelerated Failure Time (AFT) model, a parametric survival analysis technique. Under the assumption that the working circumstances of the C/C (Container Crane) are the same, we find that the productivity of on-board work of the vertically placed container terminal is higher than that of the horizontally placed container terminal. Our result also shows that the productivity is reduced during the COVID-19 period and the European ships show lower onboard work time. On the basis of these findings, we propose strategies to improve the productivity of vertical container terminals.

• Journal of the Korean Society of Industry Convergence
• /
• v.23 no.2_2
• /
• pp.323-332
• /
• 2020

Container ships are getting bigger due to the increase in global cargo volume. Therefore, it needs to increase the speed for loading and unloading of containers at the quayside. Traditionally, only one container is handled at once at the quayside due to it's heavy weight. In this paper, a method of handling multiple containers at once using chassis is proposed. Proposed system is consists of a container chassis that can hold three layer stacked containers, transport system that can handle the container chassis including rail-based or vehicle-based roll-on roll-off systems, and dedicated crane system. The conceptual design of crane and transport system that can handle three stacked containers is carried out and verified. The proposed system can be adopted for real quayside container handling system with high speed.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.33 no.1
• /
• pp.35-49
• /
• 2008

To load a container in a yard block onto a ship, a Transfer Crane (TC) moves to a target yard bay, then its hoist picks up a selected container and loads it onto a waiting Yard Truck (YT). An optimal routing problem of Transfer Crane is a decision problem which determines a given TC's the visiting sequence of yard-bays and the number of containers to transfer from each yard-bay. The objective is to minimize the travel time of the TC between yard-bays and setup time for the TC in a visiting yard. In this paper, we shows that the problem is NP-complete, and suggests a new formulation for it. Using the new formulation for the problem, we investigate some characteristics of solutions, a lower and upper bounds for it. Moreover, our lower and upper bound is very efficient to applying some instances suggested in a previous work.

• Journal of Institute of Control, Robotics and Systems
• /
• v.5 no.5
• /
• pp.630-639
• /
• 1999

To achieve fast loading and unloading of containers from a container ship, quick suppression of the remaining sway motion of the container at the end of each trolley stroke is crucial. Due to the pendulum motion of the container and disturbances like sind, residual sway always exists at the end of trolley movement. In this paper, the sway-control problem of a container crane is investigated. A two-stage control is proposed. The first stage is a time optimal controlfor the purpose of fast trolley traveling. The second stage is a nonlinear control for the quick suppression of residual sway, which starts right after the first stage while lowering the container. The nonlinear control is investigated in the perspective of controlling an underatuated mechanical system, which combines partial feedback linearization to account for the known nonlinearities as much as possible, and variable structure control to account for the unmodeled dynamics and disturbances. Simulation and experimental results are provided.

• Journal of Fisheries and Marine Sciences Education
• /
• v.25 no.4
• /
• pp.998-1007
• /
• 2013

At container terminals, a major measurement of productivity can be work efficiency. For improving the productivity of container crane, the more efficient container yard operation method is necessary in container terminals. Recently, container terminal operators make an experiment on the dual cycle operation, which ship loading/unloading were carried out simultaneously, for increasing the productivity of container crane. In this paper, propose a system operating efficient dual cycle methods as utilize Ad-hoc technology in distributed port operation system. The dual cycle methods that proposed recognizes position information of Y/T during an action in Ad-hoc networks in case of container transfer works by real time as load an Ad-hoc module to Y/T taking charge of a container transfer with quay and yard. Utilize Ad-hoc networks technology in an operating system of container yard, and efficiently distributed processing done Y/T to container crane compare with operation systems of the existing dedicated method, and an improvement can do an operating system of an yard.

• Proceedings of the KIEE Conference
• /
• 2005.07b
• /
• pp.1465-1467
• /
• 2005

In this paper, the harbor container crane which transports containers between a container ship and trucks in the harbor is modeled. The equation of motion is simplified for control purpose. The pole placement technique is used to control the crane to minimize load swing angle The objective of the control is to transfer the load as quickly as possible, while minimizing the amplitude of swing at the end of transfer. Computer simulations are provided.

• Special Issue of the Society of Naval Architects of Korea
• /
• 2005.06a
• /
• pp.165-170
• /
• 2005

The weight of a ship depends on the size of the ship. Normal lightweight of a ship is over 10,000 tons. So it is inevitable to divide a ship into about more than hundreds of lumps. Each of lumps is called as a block in shipbuilding. The sizes of blocks are decided by a yard's facilities. Among them lifting cranes are most decisive facilities. By block's size the productivity of a yard is decided very much. So it is very important to have a proper block division during shipbuilding. This paper refers to the recent trend of block division among yards. This paper would give an idea how to decide boundaries of blocks. Block division also decides both quality of a ship and work volume of it. These days the block erection method is changed dramatically due to use sea barge mounted crane for erection of a grand ring block. This paper explains the new trend of block division in shipbuilding.

• Journal of Korean Port Research
• /
• v.13 no.2
• /
• pp.255-266
• /
• 1999

The purpose of this paper is to describe the design of the decision support system for container terminal ship planning and to introduce the implemented system. The ship planning in container terminals consists of three major decision processes -the working schedule of gantry cranes the discharging sequence of inbound containers the loading position and sequence of outbound containers. For making these decision the proposed system can provide two ship planning modes the interactive planning mode with user-friendly GUI and the automated planning made. To implement the automated planning routine we acquired the planning rules from the expert planner in container terminals and developed an expert system based on the rules. Finally we evaluated the system developed and the potential for commercialization by using container terminal data.

• Journal of the Society of Naval Architects of Korea
• /
• v.47 no.1
• /
• pp.47-57
• /
• 2010

This study analyzes the dynamic response of a floating crane with a cargo considering an elastic boom to evaluate(or for evaluation of) its flexibility effect on their dynamic response. Flexible multibody system dynamics is applied in order to establish a dynamic equation of motion of the multibody system, which consists of flexible and rigid bodies. In addition, a floating reference frame and nodal coordinates are used to model the boom as a flexible body. The study also simulates the coupled surge, pitch, and heave motions of the floating crane carrying the cargo with three degrees of freedom by numerically solving the equation. Finally, the simulation results of the elastic and rigid booms are comparatively analyzed and the effects of the flexible boom are discussed.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.35 no.1
• /
• pp.115-120
• /
• 2011

The dynamic responses of a 5 MW wind turbine lifted by a floating crane with two elastic booms are analyzed. Dynamic equations of motions of a multibody system that consists of a floating crane, two elastic booms, and a wind turbine are derived. The six-degree-of-freedom (DOF) motions for the floating crane and the wind turbine are considered in the equations of motions. The hydrostatic force, the hydrodynamic force due to a regular wave, the mooring force, the wire rope force, and the gravitational force are considered as external forces. By solving the equations numerically, the dynamic responses of cargo are simulated. The simulation results are compared with those in the case of one elastic boom. Finally, the dynamic responses of the wind turbine lifted by the floating crane are analyzed under regular wave condition.