• Journal of Korean Society of Transportation
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• v.1 no.1
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• pp.64-81
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• 1983

소비자 행태에 관한 신고전 경제이론을 통행수요의 분석에 그대로 적용하는데 문제 가 되는 특기 사항으로는 운임이외에 통행시간과 같은 서어비스 질도 통행수단의 선택에 영 향을 미친다는 점과 특정 두지점간의 통행에서 동일한 소비자도 여러 수송수단을 이용한다 는 점을 들수 있다. 본 연구의 주제는 이와같은 통행수요의 독특한 특성을 반영할 수 있는 소비자의 효용최대화모형의 설정과 이 모형에서 유도된 수요함수의 구조를 분석함에 있다. 상술하면, 통행시간 가치의 불확실성 아래에서 효용을 극대화하는 의사결정문제를 Stochastic Programming 모형으로 표현하였다. 또한 이 모형에서 유도된 특성 통행수단의 수요함수는 이 수단이 가장 유리한 시간가치의 범위에 대한 부정적분으로 표현되며 이 적분 범위와 피적분함수는 모든 경쟁수단의 운임과 통행수단의 함수로 정의됨을 증명하였다. 또 한 수요함수는 통행수요에 관한 통계분석모형에서 묵시적으로 가정되고 있는 통행수단간 대 체성(Property of gross substitute)과 대각방향우세성(Property of diagonal dominance)등의 특성을 가지고 있음을 보여 주었다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.1
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• pp.147-157
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• 2013

This study developed the transit transfer mode choice model aimed Daegu transit users using multinomial logit model. Dependent variables of estimating multinomial logit model were transit transfer modes such as bus to bus, bus to subway, subway to subway, bus to others, and subway to others, and explanatory variables which affect transit transfer mode choice were sex, age, occupation, handicap, transfer area, purpose of travel and travel time. Also probability regarding explanatory variables was estimated using multinomial logit model and limit marginal analysis was carried out according to explanatory variables(cost, time). In the results, indicating goodness of fit is very reasonable as ${\rho}^2$=0.354. According to the result of marginal analysis for the selection of probability, when travel time is increased, users of bus to bus and bus to subway prefer to use subway to subway. Furthermore users of bus to bus and bus to subway prefer to use bus to others and subway to others when travel cost is increased in the result of marginal analysis for the selection of probability.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.667-677
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• 2013

The introduction of a new transit facility affects mode share of travel alternatives. The multinomial logit model, which has been the most commonly used for estimating mode share, has difficulty in reflecting heterogeneity of travelers' choices, and it has a limitation on grasping their characteristics of mode choice. The limitation may lead to over- or under-estimation of the new transit facility and bring about significant social costs. This paper aims to find a methodology to overcome the problem of preference homogeneity. It also applies market segmentation structure of separating the whole population into direct and indirect beneficiary to consider their preference heterogeneity. A mode choice model is estimated on data from Jeju Province and statistically tested. The results show that mode transfer rate of direct beneficiaries that inhabit in downtown areas increases as the new transit facility provides more advanced services with higher costs. The results and the model suggested in this study can contribute to improving the accuracy of demand forecasting of new transit facilities by reflecting heterogeneity of mode-transfer patterns.

• Journal of the Korean Society for Railway
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• v.20 no.2
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• pp.265-274
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• 2017

For accurate demand forecasting of railway logistics, we estimated intercity freight mode choice models based on the binary logit model and using production-consumption data from the Korea Transport Database. We estimated two types of models and compared the results by major item of railway logistics, such as container, cement, and steel: 1) The aggregate freight mode choice models are based on the revealed preference (RP) data and 2) The disaggregate models are based on the stated preference (SP) data. With respect to the container, the travel time variable was found to be statistically significant; however, the travel cost variable was not statistically significant in the RP model, while the travel cost variable was statistically significant in the SP model. For cement and steel, the travel cost variables were statistically significant but the travel time variables were not statistically significant in either the RP or the SP models. These results are inconsistent with results from previous studies based on SP data, which showed that the travel time variables were significant. Consequently, it can be concluded that the travel time factor should be considered in container transport, but that this factor is negligible for cement and steel transport.

• Journal of Korean Society of Transportation
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• v.19 no.4
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• pp.97-108
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• 2001

A dynamic transportation management should be applied specially in AM peak because AM peak is more critical than PM peak in traffic volume and demand. AM peak trip can be characterized by commuting and schooling. which have the high level of usage on public transportation, and constraint on arrival time. So transportation management applied in AM peak could deal with a mode choice and an arrival time constrain. Researchers were involved in the dynamic transportation assignment models for management of congested traffic network. But, there were no models which considered a mode choice and an arrival time constrain should be included in management of AM peak. So there are limits to use exist models to control and analyze AM peak traffic. In this study, it is proposed the combined dynamic transportation model, considering a mode choice and the start time selection with arrival time constrains, based on Ran and Boyce's model. The proposed model is verified the compatibility by applying to the newly designed time space expanded network. The result shows that proposed model consistent with dynamic user optimal travel pattern. From this we certificate the applicability of the proposed model to control and analyze AM peak traffic.

• Journal of Korean Society of Transportation
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• v.24 no.1 s.87
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• pp.29-38
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• 2006

After the first opening of the KTX in April 2004, travel time between major cities has been dramatically reduced. The reduction rates range from 32% to 47%. Considering travel time reduction between major cities, this study concerned about the intercity travel impact of the KTX operation. This study aimed to analyze intercity mode choice behavior of Daegu Citizens according to the first opening of the KTX. This study takes place in two sections. These are (i) the section of KTX between Daegu and Seoul, and (ii) the section of KTX between Daegu and Daejeon. This study estimated empirical models for analyzing intercity mode choice behavior according to the first opening of the KTX. This study makes use of the data from travel survey from Daegu metropolitan area. The main part of the survey was carried out in the KTX Dong-Daegu station. The survey data includes the information on travel from Daegu to Daejeon and from Daegu to Seoul. In order to analyze intercity choice behavior according to the frist opening of the KTX, multinomial model structure is used. For the model specification, a variety of behavioral assumptions about the factors which affect the mode choice, were considered. From the empirical model estimation, it is found that OVTT(Out-of-Vehicle Travel Time), OVTC(Out-of-Vehicle Travel Cost), IVTT(In-Vehicle Travel Time), IVTC(In-Vehicle Travel Cost), travel frequency, travel purpose, sex, age, occupation. household income, individual income are significant in choosing intercity travel mode. However, it is found that the intercity nde choice behavior is different between (i) the section of KTX between Daegu and Seoul, and (ii) the section of KTX between Daegu and Daejeon. Furthermore, some policy implications are discussed in conclusion.

• Journal of Korean Society of Transportation
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• v.24 no.6 s.92
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• pp.89-102
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• 2006

The purpose of this paper is to develop a dynamic OD estimating model to overcome the limitation of depicting teal situations in dynamic simulation models based on static OD trip. To estimate dynamic OD matrix we used the hybrid discrete choice model(called the 'Demand Simulation Model'), which combines travel departure time with travel mode and travel path. Using this Demand Simulation Model, we deduced that the traveler chooses the departure time and mode simultaneously, and then choose his/her travel path over the given situation In this paper. we developed a hybrid simulation model by joining a demand simulation model and the supply simulation model (called LiCROSIM-P) which was Previously developed. We simulated the hybrid simulation model for dependent/independent networks which have two origins and one destination. The simulation results showed that AGtt(Average gap expected travel time and simulated travel time) did not converge, but average schedule delay gap converged to a stable state in transportation network consisted of multiple origins and destinations, multiple paths, freeways and some intersections controlled by signal. We present that the hybrid simulation model can estimate dynamic OD and analyze the effectiveness by changing the attributes or the traveler and networks. Thus, the hybrid simulation model can analyze the effectiveness that reflects changing departure times, travel modes and travel paths by demand management Policy, changing network facilities, traffic information supplies. and so on.

• Journal of Korean Society of Transportation
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• v.28 no.1
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• pp.51-61
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• 2010

The main objective of this paper is to analyze change of travel patterns according to public transportation reform. The paper uses data collected from Gyeongsan City. So far few researches, especially using before-and-after individual travel survey, have been conducted on analyzing effects of public transportation reform. For this research, some descriptive statistical analyses and statistical hypotheses tests were conducted. Furthermore, some empirical logit models were estimated for analyzing the individual effects of the public transportation reform. Finally, some important foundings, policy implications, and limitations of this research are discussed.

• Journal of Korean Society of Transportation
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• v.8 no.1
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• pp.89-102
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• 1990

본 연구에서는 개별모형(disaggregate model)을 이용한 도시권의 교통수요예측 모형체계의 구축을 최종목적으로 하며, 그때 개인이 1일 중에 행하는 복수의 트립에 관한 의사결정간의 상호관계를 적절히 고려함에 의해, 되도록 개인의 교통행동을 논리적으로 설명함과 동시에 모형의 취급이 용이하도록 논리성과 실용성이 잘 조화된 모형의 구축을 시도하였다. 모형의 체계는 비취업자와 취업자 각각의 1일의 통행행태유형의 선택에 관한 2개의 Sub-model로 구성되어져 있다. 본 논문은 그 Sub-model중의 하나인 비취업자의 1일의 통행행태유형(트립발생, 각 트립의 목적지와 교통수단)의 선택에 관한 개별모형의 개발을 행한 것이다. 본 모형의 특징은 tour별 효용최대화행동가설에 기초를 두어 개인이 1일 중에 행하는 각 트립의 선택행동은 해당트립의 전후에 행해지는 트립들의 선택행동의 영향을 고려하여 의사결정을 하는 것으로 가설을 설정하여 트립간의 상호관련성을 표현하였다. 모형의 구조로서는, 모형의 취급이 보다 용이하도록 tour별 효과최대화를 트립단위의 단계형 모형으로 표현하는 nested logit model형의 수차동시효과최대화 모형을 구축하였다 실제의 도시권에 대한 실증적 검토를 행한 결과, 본 연구에서 개발한 별개모형의 유효성이 확인되었다.

• Journal of Korean Society of Transportation
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• v.17 no.4
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• pp.85-97
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• 1999

The Purpose of this Paper is the development of the day-to-day dynamic combined model on the evaluation of traveller's traffic information for multi-mode and multi-class environments. Information is assumed to be provided for multi-mode such as bus and automobile. and multi-class such as a driver with and without route guidance equipment when they depart for their trips. The information provision strategies have been developed in the base of user equilibrium, system optimum and in between them. The Sioux Falls network is used for the evaluation of the model and information provision strategies. In the numerical analysis, a Braess' paradox for the information provision, which is the increase of travel time even though the number of information usage level and user are increased, has been occurred so that these kinds of information strategies should be implemented with special care.