• Journal of Korean Society of Transportation
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• v.28 no.6
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• pp.133-146
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• 2010

The objective of this study is to develop a supply chain-based freight distribution channel choice model considering shippers' logistics behaviors which will be used for freight demand estimation. For this purpose, this study utilized the distribution channel data of the petrochemical and automobile industries collected by KTDB center. The distribution channel choice models for these industries were developed by including transport mode, time, cost, and shipment size. It was found that the multinomial logit model with transport cost, time and shipment size is the best, and as shipment increases, bigger transport mode is preferred. Generally direct distribution channel with small truck was preferred over the one using distribution center and/or big truck.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.6D
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• pp.697-705
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• 2010

The purpose of this research is to clarify the relation between environmental consciousness and railway usage behavior. Author would locate this research on position of basic survey to promote railway use according to Low Carbon Green Growth policy in Korea. In this research, we would perform descriptive analysis using data of research on the actual condition of railway use in 2008, Daegu, and describe its relationship. In addition, we would suggest some idea about policy which can promote railway use. The order of railway choice behavior noticed in clustering of environmental consciousness was cooperative behavior type, middle type and non-cooperative behavior type. It suggests that environmental consciousness has effect on transportation choice behavior. Specially, railway improvement isn't enough to promote railway use. And, it is advisable to carry out the improvement in such a way that it may encourage the nation to move from the current environmental consciousness stage to cooperative behavior. Moreover, we assumed Binary Probit(BP) model using SP data of time or condition of transportation expense compared with passenger car and bus. As the results, modified likelihood ratio of two BP models is favorable variables. And it occurred that mode was transferred from passenger car to railway when it showed higher social environment consciousness and low selfish environment consciousness, because t-statistic which represents selfish environment consciousness showed significance in 95% confidence level. That is, it can be described that environment consciousness affect on the intention of railway use.

• Journal of Korean Society of Transportation
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• v.26 no.6
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• pp.133-142
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• 2008

The term, travel time reliability, refers to variations in journey time that travelers cannot predict. This issue has been one of the main research topics in transport studies. This paper, especially, investigates the value of travel time reliability. The marginal substitution rate method is suggested as the way for the valuation and travelers' stated preference data are collected based on a choice experiment. A mode choice model is estimated using the data surveyed. The parameters of travel costs and travel time reliability from the model are used to calculate the marginal substitution rate that is interpreted as the value of travel time reliability. The value is arranged by travel areas of intercity and urban trips and by journey purposes of working and non-working types. The result of this research is expected to be helpful of conducting more cautious economic feasibility studies of transport schemes.

• Journal of Korean Society of Transportation
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• v.23 no.5 s.83
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• pp.65-71
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• 2005

Area type is often used in freight demand analysis and logistics planning models. For example, in freight transportation planning. area type variable is most often commonly used in freight generation (attraction) model. Yet a reliable, forecastable and measurable definition or area type is generally not documented. In fact, there is little literature on the subject of predicting area type in the context of freight planning models. This can be troublesome when applying models to long-range logistics planning where significant changes in population and employment result in changes in the general character of an area. Through the use of Discriminant Model, GIS (Geographic Information System) analysis and Delphi methods, this paper presents the successful exploration for a quantifiable means of determining area type.

• Journal of Korean Society of Transportation
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• v.30 no.1
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• pp.7-18
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• 2012

This study suggested a method of forecasting market-share of each mode after introducing new urban rail transit lines. The study reflected the observed market share of presently operating urban rail transit into forecasting process in order to improve accuracy in predicting market share of each modes. For more realistic representation of the forecasting model, we categorized O/D pairs according to attributes of trip distance, access time and number of transfers. The analysis results of traveler's mode choice behavior with observed data showed that the trip distances are longer, the share of urban rail tends to be higher, and that the number of transfers is fewer and the access times are lesser, the share of urban rail also tends to be higher. Then, incremental logit model was used in estimating mode choice probabilities for O/D pairs along with rail transit lines while utilizing observed market shares of each modes and differences in transit service level. As the next step, the market share of rail transit after introducing new rail transit lines was forecasted by using incremental logit model with the intial share values calculated the previous analysis step. It also reflected changes in level of service for automobile in highway due to changes in highway systems and changes in mode shares after introducing new lines of rail transit. It can be expected that the proposed method would more realistically duplicates phenomena of mode choice behavior for rail transit and that it would be more theoretically logical than the typical existing methods using SP data and incremental logit model or using addictive logit model in this country.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.13 no.2
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• pp.68-79
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• 2014

This paper analyzes the characteristics of trip chaining activities of elderly and explores temporal and spatial distribution. The research also estimates ordered probit model and binary logistic model to investigate various factors affecting trip chaining and mode choice patterns. We utilized household survey data for elderly conducted in 2006 and 2010 in Seoul metropolitan area. Research results indicate that trip chaining showed an increasing trend and simple trip chaining counts for more than 85%. GIS mapping expressed spatial distribution of trip departure and arrival areas, particularly showing regional changes in job-related trips. We also found that more factors influence trip chaining in 2010, compared with 2006, and travel cost is more sensitive than travel time in determining travel mode. The research contributes to establish transportation policies based on travel behavior of elderly in a upcoming super-aged society.

• Journal of the Korean Society for Railway
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• v.17 no.1
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• pp.79-85
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• 2014

This paper presents an evaluation method that considers the weights of many characteristics of a public transportation system; this method facilitates the selection of suitable advanced transit system in a transportation investment plan. The method sets up twelve evaluation items separated by the following influence factors: users, community, government and operators. It then evaluates the advanced transportation system by analyzing the weights. For an empirical analysis, the urban advanced transportation systems for the main transit of small and medium sized cities were evaluated using the AHP method. The result revealed that the weight order is safety, rapidity and punctuality, convenience, and regional activation, and the priority order is steel wheel-type AGT, LIM, and rubber wheel-type AGT.

• Journal of Korean Society of Transportation
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• v.29 no.1
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• pp.81-93
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• 2011

This research deals with the multi-modal continuous network design problem to resolve the transportation policy problems for constructing and operating transportation facilities with considering the mutual decision-making process between transportation operator and user in the multi-modal network. Particularly, in the consideration of changes in travel pattern between transport modes due to the changes in transportation policy, road network for passenger car and transit network for public transportation are considered together. In the development of network design model, more rational Stackelberg equilibrium(cooperative game) rather than more general Nash equilibrium(non-cooperative game) approach is used and sensitivity analysis considering transport mode is used. A multi-modal continuous network design model in this study is developed for the arbitrary continuous network design parameters(${\epsilon},\hat{\epsilon},p$) of transportation policy decisions. As examples of application and evaluation for these design parameters, the developed model is applied to calculate 1)the optimal capacity of road link in the road transport policy, 2)the optimal frequency of transit line in public transport policy and 3)the optimal modal split in transport modal share policy.

• Journal of Korean Society of Transportation
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• v.30 no.6
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• pp.59-70
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• 2012

The relative importance of leisure trip has been increased after adopting the five-day workweek system and considering the higher income level. Thus, the value of travel time for intercity leisure trips should be estimated to conduct a reasonable benefit/cost analysis for railway construction projects. In this paper, the value of travel time was estimated separately for each trip purpose such as business, leisure, and other non-business than leisure. The estimated values of leisure travel time ranged from 5,310 to 14,185 (won/hr) by altering travel mode, and were increased by 42-107% when comparing with those of non-business travel time. Besides, how to apply the value of intercity leisure travel time for B/C analysis of railway projects was suggested. For the construction case of a railway connecting Chuncheon and Sokcho, the estimated benefit was increased by 2.3%.

• Journal of the Korean Society for Railway
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• v.12 no.3
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• pp.348-356
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• 2009

The objective of this paper is to estimate the DMT utility function for the transportation mode choice using SP survey. With the freight OD data the estimated utility function can be used as a basic data for forecasting DMT market. 3 alternatives of transportation mode are considered in SP survey; railway, road and DMT. The utility functions are developed according to the freight items, which are container, steel and chemical product. In this study the attribute variable are chosen as time, cost and reliability. The number of level for attribute variables are 3. The high valve is determined as +10% above the standard and the low value -20% below the standard.