• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1743-1753
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• 2011

Seoul Metropolitan Government has performed alternative transit system, light rail transit(LRT), for settling the problems of urban public transit system based on conventional bus service and heavy rail transit(HRT). LRT projects of total 8 lines(about 73.6km), including Ui-Sinseol line, have been planned as Build-Transfer-Operate(BTO) projects. For the first LRT, Ui-Sinseol line, however, design of structure had met standard for design of HRT, because of no domestic design code for LRT when participates of Ui-Sinseol project submitted the design proposal. This case study reports a successful example of LRT design minimizing the scale of stations designed in base of HRT code. The problems, like oversized structures compared with LRT vehicles, excessive costs for construction, had been resolved through negotiations with the participates of Ui-Sinseol line. Result suggests that present and future costs for construction and maintenance of the LRT projects in Seoul be considerably reduced in advance.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.1
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• pp.38-55
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• 2013

This study has been performed to select several indicators of long-range transport process that can be applied to the Northeast Asia. We first classified high air pollution days into long-range transport (LRT) dominant cases and the local emission dominant (LED) cases based on the synoptic meteorological variables including vorticity and geostrophic wind speed/direction at a geopotential level of 850 hPa. LRT cases were further categorized into two types: LRT-I type with air mass pathways from northern China and/or Mongolia, and LRT-II type from central and southern China. In each categorized case, we examined the difference of both measured aerosol optical properties of AERONET at two sites in western Korea, and the simulated characteristics of LRT process by MM5-CMAQ model. We contrasted LRT case with LED case, and then generated the LRT indicators applicable to Northeast Asia. The results showed that fine and coarse modes of LRT-II were relatively smaller than LED and LRT-I cases, respectively. Aerosol size distribution showed significantly higher concentration of fine-mode particle (mainly smoke or urban aerosols) in LED case in comparison with that of LRT groups (LRT-I, II), suggesting the amplitudes fine modes of LRT relative to LED as a possible LRT indicator. From the results of MM5-CMAQ modeling, we concluded that the conversion ratios for sulfur ($F_s$) were the most effective indicators of LRT cases, and the ratio of VOC to NOx and NOx to CO were found to be the second most effective indicators of LED case.

• Journal of the Korean Statistical Society
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• v.27 no.3
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• pp.251-264
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• 1998

When the LRT is not feasible, we define quasi-LRT(QLRT) as a modification of the LRT Under some appropriate conditions the QLRT shares Bahadur optimality and Bartlett Adjustability with the LRT. When we can find maximum likelihood estimator under the null parameter space but not under the unrestricted parameter space, our QLRT is Bahadur optimal as is the LRT We suggest the stopping rule of the Newton-Raphson iterations for constructing the QLRT statistics which are Bartlett adjustable.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.2
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• pp.142-158
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• 2012

This paper investigates the physical and chemical characteristics of long-range transport (LRT) process of air pollutants by employing the MM5-CMAQ and its comparison with local emission dominant (LED) case over northeast Asia. We first classified high air pollution days into LRT and LED cases based on the synoptic meteorological variables of vorticity and geostrophic wind speed/direction at a geopotential level of over 850hPa. LRT cases are further categorized into three types of transport patterns (LRT-I-III) according to the air mass pathways from source regions. LRT-I-III are originated from northern, central, and southern China, respectively, identified by back trajectory analysis. Three LRT-I-III groups have different and unique locations of high pressure and transport pathways. The chemical characteristics showed that the simulated spatial distributions varied in terms of locations of maximum concentrations and the temporal variation of surface concentrations. The primary air pollutants such as $NO_x$, $PM_{10}$ and $SO_2$ of all of three LRT cases are well transported into Korea peninsula with different concentration levels. Of LRT cases, LRT-II has the greatest effect on air quality of Korea peninsula, followed by LRT-I and LRT-III. In comparison with LRT, the LED case shows relatively higher air pollution concentrations in general, but showed a variety of different air quality levels following the emission strength pattern. These widely varying patterns are impling the case dependent multi-directional approach for the development of indicators of long-range transport process over northeast Asia.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.569-570
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• 2006

• Journal of the Korean Society of Systems Engineering
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• v.8 no.1
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• pp.9-19
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• 2012

The Light Rail Transit Project is a large scaled project which takes several years in building a system. After construction, LRT system is operating for several tens of years. For these characteristics, the right application of systems engineering to LRT project greatly effects the project success. In this paper, we present systems engineering application model to LRT project i.e. SELRT which include systems engineering technical process, core technology management process, project support process. SELRT also has a module for the exchange of outputs in SE tool and PM tool. Systems engineering processes in SELRT mainly base on ISO/IEC 15288. In future, we expand the range of SE processes and improve the usability in SELRT. We expect that this model will contribute to improve the efficiency in LRT project and to success the LRT project.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.247-254
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• 2011

This paper is a study on the practical Systems Engineering Management Plan(SEMP) for the LRT Project. A SEMP shall be developed and applied to define and manage the systems engineering activities during the beginning of LRT Project. This paper is addressed contents and description of the practical systems engineering management plan based on the existing practices about system engineering management plan in LRT Project domain as well as the systems engineering standard as MI-STD 499A, IEEE 1220 etc. In the early stage of a LRT Project, An acquirer should provide a Systems Engineering Plan(SEP), and a contractor should summit a Systems Engineering Management Plan as the SEP in proposal. This addressed the SEMP as an aspect of the system and sub-systems supplier to systematically and effectively accomplish the systems engineering activities in LRT Project generally.

• Proceedings of the KSR Conference
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• 2003.10b
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• pp.98-103
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• 2003

Recently, to solve the urban transportation problem, the introduction of Light Rail Transit system has been proceeded positively. therefore, development of the Korean standard LRT system in which safety, efficiency and cost effectiveness are emphasized. The Korea Railroad Research institute study on Rubber Tired AGT system of Light Rail Transit to obtain the essential technology and engineering know-how, which leads lower LRT construction cost. In the development procedure, SE(system Engineering) is needed for combination of subsystem and optimum operation effect. This study is focused on the interface of LRT subsystem(Development of the rubber tired LRT, Power supply system, signalling and train control system, Elevated track structure for the rubber tired LRT), a important part of SE, to develop of the driverless LRT system and establish the test and evaluation.

• Proceedings of the KSR Conference
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• 2003.10b
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• pp.516-521
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• 2003

The presentation and development of LRT(light rail transit) is one of the effective solution to reduce the heavy traffic problems of urban area The metropolitan cities and operation companies of urban transit railway are driving to. construct the LRT system because of the advantage of construction cost and environmental serviceability. Up to now, the design criteria of structures for LRT is not established. Therefore, this paper presents the structural design criteria for LRT with rubber wheels. The proposed code provides a means of establishing minimum standards for acceptance of design and construction of LRT. In order to improve the proposed design criteria, some details will be tested and evaluated in test line.

• Proceedings of the KSR Conference
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• 2001.10a
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• pp.453-458
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• 2001

LRT (Light Rail Transit) is one of the transport modes to reduce heavy traffic in big cities and intercity. LRT line is considered to be easily linked with other transport system. The importance of new LRT lines has recently emerged as the problems solution in Korea. Thus, in this study, the turnout for AGT (Automated Guideway Transit) by computer system has been developed. And Guideway for AGT has also been developed for installation on the LRT line as well. In future, if the results of the feasibility study show the new LRT line project is viable, Kangwon Railtech shall propose design for LRT turnout, development, standardized design for guideway, and construction scheme