• Journal of Korean Society of Transportation
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• v.29 no.2
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• pp.81-89
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• 2011

Trip distribution is the second step of the conventional travel demand estimation process, which connects trips between origin and destination, while transport mode choice is the third step of the process, which chooses transport mode among several modes serving for each origin-destination pair. Although these two steps have closely connected, they have been estimated independently each other in the estimation procedure. This paper presents an integrated model combining trip distribution and transport mode choice, and also presents its solution algorithm. The model integrates gravity model adopted for the trip distribution process with logit model employed for the mode choice process. The model would be expected to cope with the inconsistency issue existing in the conventional travel demand estimation procedure. This paper also presents an equilibrium condition, sensitivity of the model, and compares them with those of existing models.

• Journal of the Economic Geographical Society of Korea
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• v.19 no.1
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• pp.68-82
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• 2016

Destination choice analysis is an important issue of transportation demand research. The current study analyses the influential factors for university students' trip destination choice. The university students differ from other population groups in many aspects. The study is concerned with shopping, leisure and amusement purposes of trips, other than obligatory trips such as going to school. University students' daily life differs from those of employees and middle and high school students in the sense that a lot of flexible activities are mixed with fixed activities such as work and school attending. A multinomial logit analysis investigates the significance of the impact of a set of variables including residential location, gender and income of the university student. The results show that these variables affect the destination choice of shopping, leisure and amusement. The analysis also provides interesting interpretation of the relationships of the variables with the location choices, which are particularly relevant to the university students.

• Journal of Korean Society of Transportation
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• v.30 no.3
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• pp.107-118
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• 2012

The purpose of the study is to analyze the travel characteristics of freight trucks in metropolitan areas, focusing on activity generation, destination choice, and trip chaining behaviors. The results showed that the number of service companies at departure areas has a primary influence on the activity generation pattern and destination choice behavior of trucks in metropolitan areas. The number of trips within a trip chain is largest, in case where the prevailing industry in destination areas is wholesale or retail and the shipment item is food or beverage. These results imply that for the reasonable estimation of truck travel demand both the trip chaining behaviors and the industrial compositions in departure and destination areas should be separately considered for each type of commodity.

• Management Science and Financial Engineering
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• v.15 no.1
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• pp.51-69
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• 2009

A network model and a Genetic Algorithm (GA) is proposed to solve the simultaneous estimation of the trip distribution and traffic assignment from traffic counts in the congested networks in a logit-based Stochastic User Equilibrium (SUE). The model is formulated as a problem of minimizing a non-linear objective function with the linear constraints. In the model, the flow-conservation constraints are utilized to restrict the solution space and to force the link flows become consistent to the traffic counts. The objective of the model is to minimize the discrepancies between two sets of link flows. One is the set of link flows satisfying the constraints of flow-conservation, trip production from origin, trip attraction to destination and traffic counts at observed links. The other is the set of link flows those are estimated through the trip distribution and traffic assignment using the path flow estimator in the logit-based SUE. In the proposed GA, a chromosome is defined as a real vector representing a set of Origin-Destination Matrix (ODM), link flows and route-choice dispersion coefficient. Each chromosome is evaluated by the corresponding discrepancies. The population of the chromosome is evolved by the concurrent simplex crossover and random mutation. To maintain the feasibility of solutions, a bounded vector shipment technique is used during the crossover and mutation.

• Journal of Korean Society of Transportation
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• v.7 no.1
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• pp.35-42
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• 1989

The multinomial logit model has been applied for various choice problems. Among others, the joint destination mode choice, the mode choice and the route choice are the three major modeling topics for korean transportation planners. This paper examines with real world data (the Olympic road and its competing two major arterials) the usefulness of a Logit route choice model. Quites surpisingly, it is found that the multinomial route choice behavioral model calibrated for this study based on (0,1) individula data base can not provide a good estimate for O-D trips less than 6㎞. 400data points and 3case studies might not be sufficient for a sound conclusion. It is, however, believed from a series of similar studies conducted by the authors that the route choice behavior is more sensitive (more demand elastic with respect to travel time changes) than the mode choice and the shorter trip, the more sensitive. The travel time parameters for destination choice models are usually smalle than the travel time parameters for mode choice models and these parameters (for mode choice models) turn our smaller than the travel time parameters for route choice models from this study. Table 2 in this paper shows parameter changes for three different markets and Table 3 shows the modeling errors when the estimated individual probabilities are aggregated into a route level.

• Journal of the Korean Geographical Society
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• v.44 no.3
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• pp.323-338
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• 2009

This study analyzes the changes in commuter's mode choice between 2002 and 2006 according to the implement of the integrated public transit system in Seoul metropolitan city. Especially this study focuses on differential changes in a transit modal choice among socioeconomic status, trip purpose and spatial characteristics of origin and destination. The probability of public transit use against automobile is modeled as a function of socioeconomic variables, spatial characteristics of origin and destination and the utility of the commuter's mode. The results from conditional logit model analyses suggest that people with lower income show the larger changes in the ratio of public transit choice between 2002-06. Also both higher density, more accessible to public transit and more diverse land uses in residence zone and in work place generally increase the ratio of public transit choice between 2002-06. Car and subway have the most strong alternative relation in commuter's mode choice. The findings give an important implication that the integrated public transit system has differential impacts on commuter's mode choice in Seoul.

• Journal of Korean Society of Transportation
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• v.27 no.1
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• pp.73-81
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• 2009

While various factors in passenger and freight demand analysis affect on destination choice, a key factor, in general. is an attractiveness measure by size variable (e.g., population. employment etc) in destination zone. In order to measure the attractiveness, some empirical studies suggested that disaggregate gravity model are more suitable than aggregate gravity model. This study proposes that truck travelers trip diary data among Korean commodity flow data could be used to estimate the behaviors of incorporating trip departure time, activity duration and attractiveness in destination. As a result, the main findings of size and distance variables coincide with the conventional gravity model having a positive effect of population variable and a negative effect of distance variable. Due to disaggregate gravity modeling, the unique findings of this study reports that small trucks are more likely to choose short distance and early morning, morning peak and afternoon peak departure time choice. On the other hand, large trucks are more likely to choose long distance and night time departure time choice.

• Environmental and Resource Economics Review
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• v.19 no.3
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• pp.547-569
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• 2010

The purpose of this study is to estimate the benefits associated with the opportunities of multiple destination trips using a mixed logit model. The opportunities that affect the destination choice can be one of the external environments of recreational sites. The data for this study were taken from a survey conducted to the multiple destination trip participants at Seorak National Park in Korea. The results of the research show the specific values of complementary opportunities in the study area.

• Journal of Korea Planning Association
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• v.54 no.1
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• pp.52-66
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• 2019

Travel is a factor that stimulates the vitality of the urban and is widely used as an indicator of sustainable growth of the region. In Korea, however, no studies has been made to predict changes in traffic and calculate the accessibility of the region by comprehensively considering the socio-economic conditions of the travelers. The purpose of this study is to classify commuters according to the household income and to analyse the traffic characteristics of each class. The analysis results are aggregated into two. First, the analysis of study found different transport characteristics for different income classes. This is the result that underpins the argument of a previous study that suggested that a discriminatory approach is necessary for each income in determining the accessibility of the region. Second, this study calculated utility values differently for each income class based on the transit time and cost required between each zone. Through these measures, transport characteristics were analyzed by income class using indicators that considered transportation infrastructure, and socio-economic conditions of the travelers. This study is meaningful in that it provided the basis for calculating the accessibility that could take into account the activities of the housing consumers in establishing domestic housing policies.

• Journal of Korean Society of Transportation
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• v.26 no.6
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• pp.7-15
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• 2008

Due to the limitations in the statistical data, the existing studies adopted rough methodologies with strong assumptions in the estimation of international passenger travel demand forecast in the ASEAN region. This study aims to develop international passenger travel demand models using scientific methodologies. This study proposes a direct demand model using the immigration and emigration data between countries in the region. This is because of the difficulty of estimating trip generation and trip distribution separately due to the data limitation in the region. As there does not exist the mode choice model for the region, this study estimates a mode choice model using the Stated Preference technique. The mode choice model is separated into three categories of models according to the range of distance between the origin and destination of travel; this is to reflect the different behavior in mode choice according to the travel distance. The result of model estimations suggests that the estimated models produce resonable results statistically. It is expected that the proposed models are useful for the future travel demand estimation in the ASEAN region.