• Journal of Electrical Engineering and Technology
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• v.13 no.4
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• pp.1459-1473
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• 2018

This paper focuses on voltage control schemes for multi-terminal low-voltage direct current (LVDC) distribution systems. In a multi-terminal LVDC distribution system, there can be multiple AC/DC converters that connect the LVDC distribution system to the AC grids. This configuration can provide enhanced reliability, grid-supporting functionality, and higher efficiency. The main applications of multi-terminal LVDC distribution systems include flexible power exchange between multiple power grids and integration of distributed energy resources (DERs) using DC voltages such as photovoltaics (PVs) and battery energy storage systems (BESSs). In multi-terminal LVDC distribution systems, voltage regulation is one of the most important issues for maintaining the electric power balance between demand and supply and providing high power quality to end customers. This paper focuses on a voltage control method for multi-terminal LVDC distribution system that can efficiently coordinate multiple control units, such as AC/DC converters, PVs and BESSs. In this paper, a control hierarchy is defined for undervoltage (UV) and overvoltage (OV) problems in LVDC distribution systems based on the control priority between the control units. This paper also proposes methods to determine accurate control commands for AC/DC converters and DERs. By using the proposed method, we can effectively maintain the line voltages in multi-terminal LVDC distribution systems in the normal range. The performance of the proposed voltage control method is evaluated by case studies.

• Journal of Korean Society of Transportation
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• v.17 no.1
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• pp.159-171
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• 1999

This Paper aims to develop container terminal simulation models for medium and long term decision makings. It first undertakes in-depth survey of literature. finds its shortcomings and suggests some directions for improvement. It then proposes detailed design for the simulation models. Based on this it finally developes several simulation models and applies them to a hypothetical situation of a container terminal development. The results reveal that basic design questions such as length of quay, number of quay crane, size of storage area are well produced through the models.

• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.49-52
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• 2002

Super Capacitors are now commercially available. To design an energy storage system with these devices it has to be understood that the device cannot be described by a single fixed capacitance. Furthermore, an internal charge redistribution process makes it difficult to predict the terminal voltage accurately. As a result, the device should be operated as a charge storage device and not as a voltage source. This paper deals with Energy Storage System with Super Capacitor for PV System. Discussed in this paper we, explains the basic characteristics of Super Capacitor which is compared with the Second Batteries.

• Journal of Korean Society of Transportation
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• v.11 no.3
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• pp.49-66
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• 1993

The successful management of logistics in an organization requires the careful coordination and manipulation of both movement and storage. In this study, we can show what is the most efficient and the cheapest method to transport the petroleum products under a few constraints with the model of linear programming. And also, the model can give some important informations so as what is the best coverages of each terminals by types, how many products should be exchanged among each companies and which terminals or complexes are economically prior to the others. Even we can understand that the duality is one of the useful measures to evaluate the economical efficiencies of transportation and storage related elements such as complex and terminal location, transport mode, storage tankage capacity and in/outflow facilities of terminals etc.

• Journal of the Korean Institute of Navigation
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• v.11 no.1
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• pp.39-65
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• 1987

Since the middle of 1950's, containerization has been rapidly spread over the world in virtue of great merits providing to interensts, and the fundamental changes in port management and prot operations are resulted. As the container terminal is a complex system which is consisted of various subsystems, the treatment for improving the productivity is required in a comprehensive fashion, both in each of its parts and as an integrated system. This paper aims to make an intensive analysis of the Busan Container Terminal system, especially focusing on its subsystems such as ship operation system, storage system and transfer system. First of all, the intrinsic capacity of various subsystems is calculated and it is checked whether the current operation is being performed effectively through the formal analysis. Secondly, the suggestion is presented to improve the operation by considering the throughput that the port of Busan will have to accept in the near future. The results are as follows; 1) As the inefficiency is due to the imbalance between various subsystems at Busan terminal, transfer equipment level must be up to 31% for straddle carrier and 67% transfer crane above all. 2) The yard capacity must be increased by reducing the free dwell time of containers in order to accept the traffic volume smoothly in the near future. 3) The better way to reduce the port congestion is to change berthing rule from the FIFP to the Pre-allocated system by considering the ship arrival pattern.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.345-352
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• 2006

The purpose of this paper is to evaluate the efficiency of two yard layout of HSS at container terminal, one is that the container yard blocks are placed horizontally in parallel with berth, the other is that the yard blocks are arranged vertically in perpendicular to the berth. In stevedoring system of container terminal, stacking and transport performance are influenced according to block arrangement type of yard. Therefore, efficient design that can improve stacking and transport performance is required. In this paper, we compared their efficiency of two block arrangement concepts in terms of storage capacity, productivity, facility investments, truck service level.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2001.11a
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• pp.335-354
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• 2001

.Next Generation Multimedia Streaming Technology Massive Scale Support $\rightarrow$ Clustered Solution Adaptive to Heterogeneous Network daptive to Heterogeneous Terminal Capability Presentation Technique .SMART Server Architecture .HERMES File System .Clustered Solution . High Speed Storage Interconnect .' Content Partitioning . Load Management . Support for Heterogeniety . Adaptive End to End Streaming Transport: Unicast vs. Multicast '. Scalable Encoding

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2003.10a
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• pp.202-208
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• 2003

• Animal cells and systems
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• v.5 no.1
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• pp.85-90
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• 2001

Yolk platelets, one of the main food stores in the embryonic development, are composed of proteins. However, little is known about the identity of proteins utilized at certain stages of embryogenesis. In this study, we followed the fates of embryonic storage proteins by using an anti-polyubiquitin monoclonal antibody (mAB) as a probe. The mAb recognized the major storage proteins of Drosophila, Xenopus and chicken eggs. In the Drosophila embryo, the mAb-reactive 45-kDa protein was not used until stage 11 but was used up at stage 16 when the embryo completed segmentation. In the Xenopus embryo, the mAb-reactive 111 kDa protein was mostly utilized between stages 42 and 45 implying that the protein might be an energy source used just prior to feeding on food. By N-terminal sequencing the storage protein of Xenopus embryo was identified as a lipovitellin 1. This study confirms that storage proteins are used almost simultaneously at certain stages of embryogenesis and that vitellogenin 1 is the last storage protein in Xenopus embryogenesis.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.407-412
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• 2004

A problem of handling capacity calculation of berth is very important factor for decision about a port development scale like as the number of berth, size of back storage yard. If handling capacity per berth calculated low, the number of berth is increasing and the size of yard decided for propriety level of handling capacity. The propose of this paper is re-calculate of handling capacity for Busan container port by firstly government plan and actual result of Busan port like as waiting rate, berth share and handling capacity, and then realistic number of crane and berth share to be applied.