• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.5
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• pp.28-38
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• 2005

The De-militarized Zone(DMZ) on the Korean Peninsula is ecologically conserved and naturally developed as access to the area has been controlled in the past five decades. As a result, biodiversity and wetlands are developed very well, but they have not been sufficiently surveyed due to land mines and security reasons. Focusing on the Kyongui Line area in Paju DMZ, this study aims at examining the status of forested wetlands in detail through an on-site survey and understanding the features of forested wetlands in DMZ. The forested wetlands of Paju Kyongui Line area are inhabited by naturally grown Salix koreensis Andress. and Acer ginnale Maxim. and affected by Sacheon Basin region extensively. As the topography of this region is created of inundated area and gentle ground, it is easily affected by hydrology and irrigation and has ideal conditions as forested wetlands. In addition, forest wetlands in this area were used as agricultural land in the past but now transformed into palustrine forested wetlands after being deserted for long time. However, as construction of roads and railways increasingly blocks water paths, the coverage of Robinia pseudoacacia L. and Amorpha fruticosa L. is on the rise, which indicates that forestedwetlands are gradually becoming inland over time.

• The Transactions of the Korean Institute of Power Electronics
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• v.4 no.6
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• pp.491-499
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• 1999

This paper is on the high perfonnance propulsion IGBT VVVF inverter adopted new technique for railways. To prove the high performance and stabilit~r of traction, running tests are carried out under the simulated condition alike real field. The tests are perfonned on not only a steady states but also a transient states such a as input voltage variation using inertia load equivalent to 160tons train. The vector control technique is a adopted to improve traction for 4 motors. The low switching synchronous PW1\l method based on a space v voltage vector modulation is pro\XlSed as the optimal method for propulsion system railway. The output voltage l is controlled continuously to six step by prolxlsed ovennodu]ation technique without sudden torque variation.

• East Asian Journal of Business Economics (EAJBE)
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• v.10 no.4
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• pp.47-54
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• 2022

Purpose - In today's era of carbon neutrality, railways need to find ways to improve usability and efficiency. Accordingly, this study examines the effect of introducing express highspeed railways into the Korean public transportation system and suggests some practical guidelines. One concern in the Korea railway sector is that low scheduled speeds contrast with the highspeed railway system design. Research design, data, and methodology - Current literature and foreign cases are analyzed. Subsequently, using data from the Korean Railroad Research Institute, a benefit analysis is conducted based on expanded track capacity and the saving of time owing to the introduction of the express highspeed railway. Result - The express highspeed railway system is expected to increase the number of train lines from 262 to 348 and the scheduled speed from 168.3km/h to 192.2km/h. Considering reduced time value, the economic effect is about 80 million won per year. Conclusion - The findings suggest that the express highspeed railway is a promising option to improve efficiency and increase customer utility. This study contributes to the literature by initiating a discussion on the express system in Korea; practically, it offers railway operators guidelines for improving highspeed railway system efficiency that can be transformed into a variety of marketing options.

• Journal of Distribution Science
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• v.19 no.9
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• pp.5-17
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• 2021

Purpose: As mobile devices are commonly used and contact-free services are widespread due to the COVID-19 pandemic in the recent distribution environment, this study suggests retail strategies for consumers using high-speed railways. To this end, we analyzed how consumer perception on technologies necessary for use of mobile apps is related to the attitude that drives consumers to continue using the app services. Research design, data and methodology: Based on the extended unified theory of technology acceptance and use of technology model by Venkatesh, Morris, Davis and Davis (2003), we added variables proposed by existing theories that studied the technology acceptance model from multiple perspectives and empirically analyzed the relationship between user satisfaction and use intention with structural equation modeling. Results: As expected, factors necessary for the use of app services such as performance expectancy, social influence, price value, facilitating conditions, security, and aesthetics had positive effects on user satisfaction, whereas the effect of effort expectancy on user satisfaction was rejected. And user satisfaction was found to have a significant effect on intention to use. Conclusions: The results provide implications that strategic retail management of the above factors can motivate passengers to continuously use high-speed railways.

• Journal of Distribution Science
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• v.4 no.1
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• pp.53-78
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• 2006

We call this world network society. Logistics is one of important network systems which connect people, materials and information. The World Economy Conditions of 21st Century has been Changed so rapidly. These Changes are more conspicuous in Northeast Asia than other Regions. China, North Korea and Russia have reformed their Economical and Social Systems, which enlarged the Trade Volume and Traffic Demand in this Area and between Europe. The Railway System Crossing the Eurasia Continent, such as TSR(Trans Siberian Railway), TCR(Trans China Railway), TMR(Trans Manchuria Railway), TMGR(Trans Mongolia Railway) and TKR(Trans Korea Railway), have been becoming very important to enhance the International Transportation efficiency and to connect each continents by International Railways. This Paper investigated and surveyed the logistical Environments surrounding this Korea Peninsula. And concerned with the Crossing Continents Railway, TSR,TCR(TMR, TMGR), TKR, operating Conditions and Tasks that must be considered and solved were also investigated. Especially the Current Logistical Conditions of China, Russia, and North Korea and their Problems were surveyed. And the SWOT of these Railways were analyzed and compared. The Visions and Goals of these Inter-Continental Railways were suggested in terms of their Rationalization of Operations and efficient Connections among many Countries. Not only the Policies and Strategies/Tactics which should be considered but also and Many detail countermeasures which should be introduced and adopted were suggested.

• Journal of the Korean Society for Railway
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• v.11 no.1
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• pp.81-94
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• 2008

Recently, most of countries have been adopting the policies that aim to deal with the Problems of road congestion, environmental problems and the decreasing the volume of rall. A vital important subject is the reform of railways. Actually, the reform of railways has been carried out in various kind of ways, however the most epoch-making policy has been privatization of railways. Historically, Japan made the first step when it carried out regional privatization, unifying the infrastructure and operation. It created a 6 passenger enterprises and 1 freight enterprise. Meanwhile, in the case of the UK, discussion about rail privatization started the middle of 1980 and was implemented in 1994. It was implemented according to a functional division based on a separation of infrastructure and operation, creating a lot of different enterprises. With regard to the UK and Japan, there have been some debates about the methods of privatization, in particular, some scholars suggest that the rail accidents in the UK are a result of division of the infrastructure and operation. In addition to, some insist that the accident which occurred on 27th April 2005 at Hukujiyama in Japan was also attributable to the emphasis on profitable management. This paper examines the process and outcomes of rail privatization between the UK and Japan, especially focusing on different methods of privatization. This paper may provide some lessens for rail privatization policy. First, the rail privatization policy needs a enough time to complete the scheme. Second it is require to participate in the consumer, mass communication and rail of ncers who are involved the operation. Third, it is essential to have a huge investment, high technology and strong organization to drive.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.614-627
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• 2018

Urban railway lines have been constructed adjacent to residential buildings and urban areas. The expansion of transportation networks and reconstruction of residential buildings in highly populated urban areas require deep excavations in areas adjacent to urban railways. Mobilized soil stresses and changes in the groundwater level induced by deep excavations results in track irregularities in urban railways. In this study, a three-dimensional finite difference model using the commercial program FLAC3D was adopted to estimate the horizontal displacements of earth retaining structures, settlements of backfill, the stability of track irregularity and underground box structure based on the criteria of each railway organization and its relationships. In deep excavations, a change in groundwater level induces relatively very small differences for track gauge irregularities, whereas relatively large differences for longitudinal irregularities of 72.5%, twist irregularities of 83.3%, cross level irregularities of 61.9%, and alignments of 43.3% were found to be the maximum differences when the horizontal displacement of earth retaining wall and settlement of backfill were 65.1% and 21.4%, respectively, because the groundwater level (GWL) on the ground surface-mobilized tensile strength of the underground box structure exceeds the allowable value. Therefore, three-dimensional numerical analysis was performed in this study. Overall, real-time monitoring should be carried out to prevent railway accidents in advance when a deep excavation adjacent to urban railway structures is constructed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.9
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• pp.508-517
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• 2018

This study evaluated the construction costs of 11 design cases to decrease the horizontal forces applied to an abutment. They include two kinds of abutment types, which are used to improve the backfill materials for reversed T-shaped abutment and geosynthehtic reinforced abutment for railways (RAR). In the first economic analysis, the internal friction angles of the backfill materials were increased from ${\Phi}=35^{\circ}$ to ${\Phi}=40^{\circ}$ and $50^{\circ}$ for a reversed T-shaped abutment. The second analysis examined cases with the design of a geosynthehtic RAR. When the friction angles were $40^{\circ}$ or $50^{\circ}$ after improvement of the backfill material, the reduction in the construction cost of the abutment was not as large (2.0-3.9%), even though the horizontal forces on the abutment were decreased by 18-48%. However, in the case of applying the RAR, a maximum cost reduction of 30% was achieved by decreasing the horizontal force to zero. The cost reduction results from the decreased wall thickness, base slab size, and the number of pile foundations for the abutment, as well as changing the material.

• Journal of Korean Society of Transportation
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• v.27 no.4
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• pp.63-76
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• 2009

On the basis of a Stochastic Frontier Approach (SFA), this paper analyses revenue efficiencies for the same sample of Korean and Japanese railways in the papers which analyze cost efficiencies using a generalized translog functional form. The paper also compares the results of revenue efficiencies with cost efficiencies and evaluates the effects of managerial autonomy and privatization on the firm-specific efficiencies. The results show that the average estimate of revenue inefficiency is 7.02% when the term of inefficiency is assumed to be distributed as a half-normal and 6.98% as a exponential for the total sample. Also, standardized inefficiencies in revenues (7.5%) are greater than those in costs (2.1%). JR East and JR West are found to be most efficient on the revenue side and on the cost side respectively while JNR and JR Kyushu are worst efficient on the both sides. Finally, the correlations between efficiencies in revenues and costs also between efficiencies and privatization are positively correlated. The results suggest that the most independent companies, with increased managerial autonomy via privatization, are the most efficient in both revenues and costs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.645-652
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• 2018

Recently, as South Korea has joined the OSJD, the rules of the OSJD need to be applied to South Korea. Therefore, the railways are connected to the continent railway in terms of software, but the railway systems in neighboring countries have been developed and operated for a long time, and are quite different with some restrictions in terms of hardware. Therefore, this study analyzed the current railway systems of neighboring countries' based on the TSI used in Europe for technical interoperability. A real operation with the operation models within the specific route was assumed and vector functions for the Infrastructure vector & Rolling stock vector were produced. The IOP value was calculated by working out the interfacing matrix value between the infrastructure vector and rolling stock vector. As a result of calculating the IOP in a specific route, which is from Busan South Korea to Vladivostok with the diesel locomotive hauling freight cars, the value was only 22%, which is fairly low in terms of the interoperability. In other words, there are 77.8% restricting items preventing their interoperability. Such restricted causes should be improved to increase the technical interoperability in the long term. Moreover, and when railway systems are constructed and manufactured, it is important to keep IOP 100% to increase the operating efficiency in continental railways.