• KSCE Journal of Civil and Environmental Engineering Research
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• v.3 no.2
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• pp.119-126
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• 1983

The purposes of this study are to analyze/model the mode choice behavior of the regional traveler by express bus/express train and to offer useful source in deciding the public transportation policy. The data analyzed were trips of both modes from March, 1980 to November, 1981, between Seoul and other nineteen cities; the data were grouped as five groups according to the change of service variables. Service variables were travel time(unit: minute), cost(:won), average allocation time(:won), service hour(:hour), and dummy variables by mode. As model Logit Model with linear or log utility function were postulated. As the result of this study, some reseanable models were constructed at Model Type I(eq. 2. of this paper) based on the above data except the dummy. It was judged that the parameters calibrated by Group III and Group IV data in table 4, were optimal. Among the parameters, the parameter of travel cost was most reliable. There was a tendency preferring express bus to train in October and November. With the constructed model and Pivot-Point Method. the demand change of express train caused by the service variables' change could be forecasted over 99%.

• Journal of Korean Society of Transportation
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• v.23 no.3 s.81
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• pp.7-19
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• 2005

Mode choice Analysis is essential analysis stage in transportation demand forecasting process. Therefore, methods for calibration and forecasting of mode choice model in aspect of practical view need to be discussed in depth. Since 1980s, choice models, especially Logit model, are spread widely and rapidly over academic area, research institutes and consulting firms in Korea like other developed countries in the world. However, the process of calibration and parameter estimation for practical application was not clearly explained in previous papers and reports. This study tried to explain clearly the calibration process of mode choice step by step and suggested a forecasting mode choice model that can be applicable in real policy analysis by using household survey data of Pusan metropolitan are. The study also suggested a way of estimating attributes which was not observed during the household survey commonly such as travel time and cost of unchosen alternative modes. The study summarized the statistical results of model specification for four different Logit models as a process to upgrade model capability of explanation for real traveler's choice behaviors. By using the analysis results, it also calculated the value of travel time and compared them with the values of other previous studies to test reliability of the estimated model.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.15 no.2
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• pp.36-49
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• 2016

A subway system is one of the major transportation modes at a metropolitan area. When it meets the other lines, the metro station, so-called transferring station, is usually threatened by severe pedestrian congestion and safety issue of transit users including the transportation vulnerable. Although transportation planners forecast travel demand at the beginning, it is not easy to predict pedestrian flows precisely for a long term if land use plans have dramatically changed. Due to expensive costs, structural extension of metro stations is limited. Therefore, it requires efficient and technical improvements as meeting the demand of pedestrian and physical characteristics. In this study, the core mechanism of pedestrian movement-based simulation model was introduced and evacuation scenarios were analyzed with the developed model. As a result, the multiple optimal routes for unexpected events at the solid space of the multiple stories are easily searched through the simulator and in the case of Sadang Station, travel time can be reduced by 60% when the evacuation information and intuitive design are provided.

• Particle and aerosol research
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• v.14 no.4
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• pp.97-105
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• 2018

Recently, people's interest in particulate matter (PM) has been increasing, due to its hazardous health effects. The purpose of this study was to investigate the concentrations and as well as the inhaled weight of PM, correlated with person's heart rate in subway, bus, vehicle and bicycle in the major public transportation (Sadang - Jamsil and Nowon - Dongdaemun) in Seoul. The concentration of $PM_{10}$ and $PM_{2.5}$ were measured from each of transportation means and calculated the average concentrations which were 87.2 and $57.8{\mu}g/m^3$ for subway, 62.8 and $42.5{\mu}g/m^3$ for vehicle, 61.5 and $36.8{\mu}g/m^3$ for bus and 53.0 and $29.4{\mu}g/m^3$ for bicycle in $PM_{10}$ and $PM_{2.5}$ respectively. Inhalation dose for $PM_{10}$ and $PM_{2.5}$ were estimated at 248.1 and $139.4{\mu}g$ for bicycle, 56.7 and $39.3{\mu}g$ for vehicle, 49.4 and $29.9{\mu}g$ for bus and 44.3 and $29.1{\mu}g$ for subway, respectively. Even though subway had the highest concentration, the highest inhalation dose was the bicycle. It was due to the long travel time-exposure and breathing rate which leads to maximum of $PM_{10}$ 5.6 and $PM_{2.5}$ with 4.8 times inhalation dose comparing with other modes of transportation. With regards to future studies, the amount of inhalation in each transportation means should be considered in risk assessments of PM.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.4D
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• pp.433-441
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• 2009

In the coming ubiquitous society, the importance of developing advanced public transportation systems (APTS) corresponding to individuals' needs and useful in their daily life is profound. In these regards, the study proposed new APTS services: Free internet access service and On-board real time traffic information service in public modes. A stated preference (SP) survey was performed to investigate individual's preference and willingness-to-pay (WTP) for the proposed APTS services. Multinomial logit models (MNL) incorporating the heterogeneity of respondents were developed to analyze individuals' preference and the difference of WTP. Some results of the study showed that the respondents' preferences were significantly different by in-vehicle travel times (30 min, 60 min) and their socioeconomic background. More respondents prefer new APTS services when invehicle travel time takes longer. For the housewife and self-employed group, the mean WTP for on-board realtime traffic information was higher than that of free internet access services, while for the company employees and students group, the mean WTP was similar in both services.

• Journal of Korean Society of Transportation
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• v.23 no.8 s.86
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• pp.31-42
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• 2005

Accessibility is the generalized definition on how ease of access. Accessibility is used to appraise transportation project such as capturing the quality of the existing state of the transportation system at diverse spatial levels, It also reflects on the effect of improvements to the existing travel modes and the intoduction of new modes. The overall goal of this study is to propose a measure of urban accessibility in Seoul which can analyze various behavior of travelers in the city and to present applications. In this study, we apply measures of accessibility which are developed by CTR(The Center for Transportation Research, the University of Texas at Austin) to construct the urban accessibility index applicable for explaining trip behavior in Seoul. We evaluate sustainability of urban transport system in Seoul in 2002 by using the MAG(Modal Accessibility GaP) index which is developed to measure the accessibility gap between the more energy-efficient mode and less energy-efficient mode of transport. By analyzing the change of MAG index between 2002 and 2004 based on network data, we show how the public transportation system reform affect the sustainability in transport system.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.3
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• pp.379-389
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• 2022

The number of public transportation users has dropped drastically due to COVID-19. In this work, my survey was conducted to uncover the factors that influence citizens' travel patterns. Data were collected and logistic regression analysis on the shifts in transportation was undertaken. Additionally, an importance-performance analysis was carried out to investigate how to effectively operate public transportation systems and improve facilities. The main research findings were as follows: First, the more individuals were concerned about COVID-19 (+) and being infected when using public transportation (+), the greater the tendency to switch to private transportation modes. Secondly, when it came to personal traits, respondents who could drive a car (+) or owned a car (+)or did more online shopping (+) or used public transportation for trips (+) tended to switch over, compared with respondents who could not drive or did not own a caror used public transportation to commute. In addition, respondents who were vaccinated (-) or had more household members tended not to switch transportation modes, compared with those who were not vaccinated or had fewer household members. Third, it is important to continue the following efforts to safeguardhygiene linked to public transportation: wearing masks, disinfecting hands, controlling diseases, and general cleaning. The conclusion was that it is important to put traffic congestion and ventilation issues first, especially in regards public transportation, which was not rated as satisfactory enough compared to its importance. The research findings can provide useful basic data when establishing countermeasures to the current COVID-19 circumstances in the areas of public transportation operation and management and in the event of an infectious disease outbreak in the future.

• Environmental and Resource Economics Review
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• v.26 no.2
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• pp.173-203
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• 2017

The existence of rebound effect from road extension in Korea has been quantitatively verified using cross-sectional, time series data on four major cities - Seoul, Busan, Daegue and Incheon - between 2000 and 2013. The linear mixed effects model was constructed from six variables: total vehicle miles traveled (VMT), road extension, public transport users, gross regional domestic product (GRDP), regional population and fuel consumption. The main results can be summarized as VMT is positively correlated to road extension while negatively with public transport users. It indicates that the road extension-centered "supply-side" transportation policy induces "additional travel" and create "generated traffic" by enhancing driving efficiencies directly, or degrading other transport modes indirectly. Hence, the ultimate goal of road congestion reduction requires public transport-centered "demand management" rather than current supply-side policies.

• Journal of Korean Society of Transportation
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• v.24 no.3 s.89
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• pp.197-205
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• 2006

The study suggested a demand forecasting method which explicitly reflects transfer between various transport modes especially related light rail transit project with multi-modal transit system. The suggested method classifies several groups depending on characteristic of trips and applies different demand model for each group to explain travel pattern more realistically More specifically. the trips was classified by trips within the LRT route, trips between inside and outside of the LRT route. and through trips via the LRT route. The study also suggested a evaluation measurement of time saving due to the LRT construction, which are consistent along with the do-case and the do-nothing-case even though some mode shift could be happen after introducing the LRT.

• Journal of Korean Society of Transportation
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• v.25 no.6
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• pp.33-42
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• 2007

This research proposes strategies about providing detour route information and traffic management for flood disasters. Suggested strategies are based on prevention and preparation concepts including prediction, optimization, and simulation in order to minimize damage. Specifically, this study shows the possibility that average travel speed is increased by proper signal progression during downpours or heavy snowfalls. In addition, in order to protect the drivers and vehicles from dangerous situations, this study proposes a route guidance strategy based on variational inequalities such as flooding. However, other roads can have traffic congestion by the suggested strategies. Thus, this study also shows the possibility to solve traffic congestion of other roads in networks with emergency signal modes.