• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.1
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• pp.109-114
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• 2006

The reformed bio-diesel fuel irradiated by the ultrasonic wave is applied to the diesel engine of common rail in common use recently. This study has the object to examine the properties of engine performance and discharged materials. The bio-diesel fuel is mixed and used with the diesel fuel in common use at the ratio of $20\%\;or\; 100\%$. The ultrasonic energy is irradiated to the individually mixed fuel in order to reform the fuel. This fuel is applied to the engine in this experiment. And It is compared and analyzed from the experimental results with two cases irradiating the ultrasonic wave and no irradiating.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1489-1497
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• 2009

The rectifier for Electric railway is one of the most important facilities in DC urban railway which converts power from KEPCO(AC 22.9kV) to the electric mil car(DC 1.5kV), therefore it should be managed as the best condition for the drive. There are several things to cause performance degradation and deterioration of parts such as pollutants occurred by it established under the ground such as dust or foreign substances, rapid changes of driving current, and pyrogen which put the rectifier for Electric railway in malfunction. On the flow of time, the rectifier for Electric railway is causing a malfunction or failure which drive electric rail car in operations as well as loss of life. In this research we try to find the way of removing the various components of mal-functions in the performance of the rectifier for Electric railway by Over-Haul and reform itself, which gives us to get the chance investment of the reduction, the reliability of power supply to the electric rail car.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.1287-1292
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• 2005

With opening of KTX, Korea Railway have carried out a variety of marketing strategies unprecedented, which have brought successful results for dramatical increasing passengers in KTX from 72 thousand passengers per day in 2004 to 85 thousand passengers per day in 2005. These marketing strategies for Korea Rail to use in increasing passengers for KTX are the following: special discount fare system for non-season to penetrate into transport market in the first time, fare system reform considering to customers' willing to pay, new item development by each specific market like contracting transport, YMS(Yield Management System) by stages, Home-ticket-and-e-ticket and tele-marketing service, and wide range covering sales network making it comfortable for users in KTX. This paper discusses these successful marketing strategies and its performance and finally suggests strategic implications for KTX growth.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.325-336
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• 2008

Deformation of caisson occurred during the backfilling behind the caisson and some caisson moved toward seaside. A series of site investigation were conducted to figure out various circumstances at site and also used to analyze the cause of deformation. The soil condition of backfilling is also investigated because dredged material was used as a backfill material. The friction angle of backfill is supposed to be lower than the estimated one which was used in design stage. To determine the cause of friction shortage, back analysis for sliding safety were carried out with considering the soil condition of backfilling. A remedial plan, re-rising and relocating a caisson with backfilling good earth after treatment of caisson rubble mound to achieve the safety for sliding was proposed as a best solution based on the back analysis results. Reform concrete structure including service gallery and crane rail was also considered with the remedial work to improve the cape line of caisson.

• Journal of Korean Society of Transportation
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• v.32 no.3
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• pp.227-238
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• 2014

There is no question that railroad investment is crucial for better transport systems and the Korean government has continued to invest in railroad facilities. Nevertheless, the modal share of railroad, in particular, for freight has decreased. This is because rail freight transport can hardly meet customer needs such as just-in-time(JIT), a door-to-door service, compared to road transport, to be specific, trucking which can directly carry the freights to the final destinations. This has made the value of the railroad infrastructure less, which has been operated for the past 114 years. This study proposes a new freight movement concept called Piggy Back System. This system can carry freight trucks on the trains and deliver the freights to the final destinations. It can make a door-to-door deliver system possible for railroad transportation, which is the key factor for modal shift from road to railroad. For implementing this, this study proposes three important things: the cost-efficient reforming way of railroad yard that has been used for the past 114 years, the diagram plan of train services, and some technical reviews like clearance limits. This is the first study with practical proposals and solutions on this topic in Korea. The suggestions of this study cut down distribution costs by more than seven trillion won.

• Journal of Korean Society of Transportation
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• v.23 no.5 s.83
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• pp.157-167
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• 2005

Seoul metropolitan public transport reform results in the introduction of the semi-public operation and distance-based fare policies. With implementation of these policies, public transport revenue allocation has been (will be) evolved very complicated because the existing revenue allocation issues have not only been clearly solved, which is generated by the combined relationship among Korea Railroad Corporation (KRC). Seoul Metropolitan Subway Corporation (SMSC). Seoul Metropolitan Rapid Transit Corporation (SMRTC), and Incheon Rapid Transit Corporation (IRTC), but also the revenue allocation problem between bus and urban railroad-related organizations need to be considered in this combined framework. On top of that. based on the future plans such as the private sector's railroad construction plan(s), the light rail transit construction plans of several local governments and the join of remained bus lines of Seoul metropolitan areas, it is understood that the revenue allocation among public transport operating organization will become one of main issues of operation organization as well as local and central governments. As a basic approach for revenue allocation of public transport operation organizations, the purpose of this paper is to propose an integrated model applicable to estimate degree of service contribution in passenger carriage in the combined public transport network. With a hypothesis that the complete electronic card system is deployed, this paper supposes every passenger's loading and alighting stations is recordable. Thereby, this paper limits research scope as to Seoul metropolitan railroad area since used route(s) between origin and destination stations can not be traceded because transfer stations each passenger path through is not recorded. Each model proposed in the paper is as follows: 1. a generalized cost reflecting passenger's transfer behavior; 2.a K path model for determining similar routes between O-D; 3.an assignment model for loading O-D trips onto the detected similar routes using Logit Model.

• Journal of Korea Port Economic Association
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• v.37 no.4
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• pp.127-144
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• 2021

The purpose of this study is to derive service factors based on the "Rail Statistical Yearbook" data of railroad service providers from 1990 to 2019, and to analyze the effect of the service factors on the operating profit ratio(OPR), a representative management performance variable of railroad transport service providers. In particular, it has academic significance in terms of empirical research to evaluate whether the management innovation of the KoRail has changed in line with the purpose of establishing the corporation by dividing the research period into the first period (1990-2003) and the latter (2004-2019). The contents of this study investigated previous studies on the quality of railway passenger transportation service and analyzed the contents of government presentation data related to the management performance evaluation of the KoRail. As an empirical analysis model, a research model was constructed using OPR as a dependent variable and service factor variables of infrastructure, economy, safety, connectivity, and business diversity as explanatory variables based on the operation and management activity information during the analysis period 30 years. On the results of research analysis, OPR is that the infrastructure factor is improved by structural reform or efficiency improvement. And economic factors are the fact that operating profit ratio improves by reducing costs. The safety factor did not reveal the significant explanatory power of the regression coefficient, but the sign of influence was the same as the prediction. Connectivity factor reveals a influence on differences between first period and latter, but OPR impact direction is changed from negative in before to positive in late. This is an evironment in which connectivity is actually realized in later period. On diversity factor, there is no effect of investment share in subsidiaries and government subsidies on OPR.