• Journal of the Korean Society for Railway
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• v.9 no.6 s.37
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• pp.766-771
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• 2006

Railway stations are important facilities for transport of passengers and freights. The location of station have an effect on the efficiency of railway transport and operation. In this study, an inspection of the primary factors for station spacing in urban railway has been performed and a review for the propriety of the present states and further improvement has been carried. It may be helpful for proper decisions on the route planning in urban railway. Primary factors for station spacing are 1)train capacity, 2)competitiveness with other transportation, 3)accessibility and 4)construction cost, which is out of consideration in the inspection. From the result of this study, the proper station spacing is about 600m for the accessibility, more over 1.03km for the train capacity and more over 1.4km for the competitiveness with other transportation.

• Electronics and Telecommunications Trends
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• v.37 no.3
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• pp.23-32
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• 2022

This paper provides an overview of optical transport technology for 5G mobile fronthaul. The configuration of fronthaul network is classified with dedicated fiber, passive WDM(Wavelength Division Multiplexing), active WDM, and semi-active WDM, which has its own advantages and drawbacks. Various WDM technology is applied for fronthaul transport, depending on the wavelength bands, required number of wavelength channels, configuration of fronthaul network, etc. In order to meet the increasing transport capacity, a 50/100 Gbps optical transceiver will be used in place of the present 10/25 Gbps technology. Trends will be continued to enhance the flexibility and reliability of the fronthaul optical network supporting highly advanced 5G mobile services.

• Journal of Korean Port Research
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• v.7 no.1
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• pp.43-58
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• 1993

There has been fast progress in economy in Korea derived by a consecutive five-year plan program for economic development started in the early 1960's. In the field of transportation, rapid changes in the technological environment of transportation and communication have brought a revolution of the transport system, of which inter-modal transportation through containerisation is typical. Because of the rapidly growing traffic volumes of cargo, especially container traffic, and lack of investment into transport infrastructure in the past, both road and railway are beyond their capacity. As a result, the public-road network has suffered a serious congestion problem. For instance, in relation to the corridor between Seoul and Pusan, today, it takes about 14 hours for the journey of container trailer through Kyongbu Expressway, for which it used to take only 7 hours in 1986. For the railway, though the congestion problem is not very serious compared with the road sector, a shortage of capacity on certain main lines has emerged as a problem as railway traffic has increased. Furthermore, the further expansion of the system in near future is difficult due to burden of higher construction the cost. Unlike these two modes, coastal shipping, which has been paid relatively less attention for commodity transport in Korea, shows no constraint in this respect. In addition, it is the most cost efficient mode of transport. This work therefore aims to make a proposal for the alternative inland transportation mode, which is to promote the coastal transport of container. Three obstructing factors for the promotion of the coastal transport are investigated and some solutions for those are suggested as follows : First, it appears to be essential to provide exclusive ports for the coastal shipping, that comply with simplification, specialization and rationalization. The optimum size of berths on the exclusive ports in Pusan port is estimated as 16-20. We found that it needs periodical study and publicity on the advantages from the adoption of the coastal mode. Inducing competition in the coastal shipping market is also necessary. For the supply of the fleet in the coastal shipping, chartering of the surplus ships in the oversea shipping is found to be more desirable than new shipbuilding. Second, to solve the fragmentation of the companies which wish to participate in the coastal transport, government has to implement the subsidy policy. The encouragement of participation of the shipping lines engaging in Korea-Japan run and Korea-East South Asia run, into coastal shipping also needs to be considered cautiously. Third, simplification of the document for entry in ports is needed for rational coastal shipping management. We can use B/L (Bill of Lading) for coastal shipping as a prerequisite to get the indemnity by P & I Club. The reduction of the government controls on entering and leaving the ports also needs.

• 한국ITS학회:학술대회논문집
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• 2008.11a
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• pp.29-36
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• 2008

• 한국ITS학회:학술대회논문집
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• 2003.11a
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• pp.153-158
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• 2003

• 한국ITS학회:학술대회논문집
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• v.2006 no.10
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• pp.160-165
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• 2006

• 한국ITS학회:학술대회논문집
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• 2005.11a
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• pp.46-51
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• 2005

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.1
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• pp.105-111
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• 2012

In this paper, we investigate the most commonly adopted networking technology for Network Centric Warfar (NCW), namely Link-16 in the perspectives of physical, data link, and network layers (specifically, strategic message exchanges) and derive its merits with some constraints therein. Furthermore, we perform a quantitative evaluation on its communication capacity, focusing on whether Link-16 can indeed meet the capacity requirements for major operations, based on the time slot structure, NPG, and multi-netting concepts.

• Journal of Korean Society of Water and Wastewater
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• v.10 no.4
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• pp.103-110
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• 1996

Excessive phosphorus (P as orthophosphate) is one of the major pollutants in natural water that are responsible for algal blooms and eutrophication. P removal by slag is an attractive solution if the P sorption capacity of the slag is significant. To design an efficient land treatment facility, basic information on the behaviour of P in the media-water environment is required. In this study, detailed column experiments were conducted to study the P transport under dynamic condition, and mathematical models were developed to describe this process. The column experiments conducted with dust and cake waste products (slag) from BHP steel industry in Australia as adsorbing media indicated that they had higher sorption capacity of P than that of a sandy loam soil from North Sydney, Australia. P transport in the dust and cake columns exhibited characteristics S-shaped or curvilinear breakthrough curves. The simulated results from a dynamic physical non-equilibrium sorption model (DPNSM) and Freundlich isotherm constants satisfactorily matched the corresponding experimental breakthrough data. The mobility of P is restricted proportionally to the adsorbent's sorption capacity.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1998.03a
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• pp.258-262
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• 1998

A structural design based of finite element analysis has been performed to investigate the reliable automatic transport system. For the procedure, different cross-sectional geometric factors were calculated and compared in detail. The von-Mises stresses were chosen to maintain a solid loading braring capacity for the safe design. Parametric studies showed that it is more inportant for the plate bending problem than the vertical loads of hanging bar to assess the safe and economic structural design.