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

• Journal of Korean Society of Transportation
• /
• v.24 no.7 s.93
• /
• pp.91-100
• /
• 2006

Travel Demand Forecasting (TDF) is an essential and critical process in the evaluation of the highway improvement Project. The four-step TDF Process has generally been used to forecast travel demand and analyze the effects of diverted travel demand based on the given Origin-Destination trips in the future. Transportation system improvements, however, generate more travel, Induced Travel Demand (ITD) or latent travel demand, which has not been considered in the project evaluation. The Purpose of this study Is to develop a model which can forecast the ITD applied theory of economics and the Program(I.D.A) which can be widely applied to project evaluation analysis. The Kang-Byun-Book-Ro expansion scenario is used to apply and analyze a real-world situation. The result highlights that as much as 15% of diverted travel demand is generated as ITD. The results of this study are expected to improve reliability of the project evaluation of the highway improvement Project.

• Journal of Korean Society of Transportation
• /
• v.27 no.6
• /
• pp.167-176
• /
• 2009

Several travel demand management schemes have been used for controlling overloaded traffics on urban area. To maximize efficiency of the travel management, traffic manager has to set target level that we try to arrive in advance, and then to find optimal variable to attain this goal. In this regard, this paper presents two travel demand management models, expressed by mathematical program, and also presents their solution algorithms. The first is to find optimal travel demand for origin-destination (OD) pair, based on average travel time between the OD pair, and the second is based on the ratio of volume over capacity on congested area. An example is given to test the models.

• Journal of Korean Society of Transportation
• /
• v.24 no.4 s.90
• /
• pp.7-17
• /
• 2006

The purpose or this paper is to investigate the relationship between highway improvement and Induced Travel Demand(ITD) focusing on the Seoul metropolitan area data. In addition, authors tried to estimate basic unit of demand elasticity focusing on zone and trip purpose which can be applied for the ITD forecasting. The results are based on the 2002 Metropolitan Household Transportation Survey Data, where the demand elasticity (DE) is -0.582 in Seoul, -0.597 in Incheon and -0.559 in Gyounggi province, respectively. This study revealed part of the relationship between highway improvement and ITD for metropolitan region and provided the framework for yielding real estimated values by applying the concept of demand elasticity in terms of the relationship by using regional and long-term data. We expect that the basic unit of demand elasticity focusing on zone and trip purpose can be applied for the ITD forecasting to analyze the whole demand exactly The estimated DE's for age group and day of week can also be used for Proper transportation management and transport Policy making. Some limitations have also been discussed.

• Journal of Korean Society of Transportation
• /
• v.24 no.3 s.89
• /
• pp.197-205
• /
• 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
• /
• v.23 no.7 s.85
• /
• pp.7-15
• /
• 2005

The objective of this study is to estimate highway trip demand functions in Korea. In order to estimate them, I propose various socio-economic variables that affect the highway trip demand functions. I use the unit root test for each variable and the cointegration test to and the relationships among variables. Finally, I use the vector error correction model, to get the highway trip demand functions. The implication which I derive from the estimation is that real GDP and highway tolls have positive and negative effects, respectively. on the highway trip demand.

• Journal of Korean Society of Transportation
• /
• v.25 no.3
• /
• pp.137-144
• /
• 2007

This study involves an analytical approach to determine transit dispatching schedules (headways) Determining a time schedule is an important process in transit system planning. In general, the transit headway should be shorter during the peak hour than at non-peak hours for demand-responsive service. It allows passengers to minimize their waiting time under inelastic, fixed demand conditions. The transit headway should be longer as operating costs increase, and shorter as demand and waiting time increase. Optimal headway depends on the amount of ridership. and each individual vehicle dispatching time depends on the distribution of the ridership. This study provides a theoretical foundation for the dispatching scheme consistent with common sense. Previous research suggested a dispatching scheme with even headway. However, according to this research, that is valid for a specific case when the demand pattern is uniform. This study is a general analysis expanding that previous research. This study suggests an easy method to set a time table without a complex and difficult calculation. Further. if the time axis is changed to the space axis instead, this study could be expanded to address the spacing problems of some facilities such as roads. stations, routes and others.

• Journal of Korean Society of Transportation
• /
• v.21 no.3
• /
• pp.7-14
• /
• 2003

Statistics shows that 80% of freeway users travel less than 50km, and only 8% of them do over 100km. It means that the freeway is used for commuting. As a result, the freeway is not used efficiently and social cost is high. The current toll system aims for the efficient usage of the freeway by restraining short-distance trips and inducing long-distance ones. Thus, policies such as minimum toll system and discount for long-distance trips have been carried out. However. these two policies take no account of demand management between the freeway and alternative roads. They merely consider the compensation for charge on users, so the assessment of discount rate and distinction of distance are not reasonable. Consequently, not only the effective demand management but also the evaluation of those policies has been difficult to be achieved. The objective of this paper is to analyze those problematic policies and to establish a reasonable and improved toll system. In addition, this study presents the methodology to minimize social cost, which can be achieved by reducing short trips and encouraging long ones on the freeway. A new methodology of freeway toll system is applied and the results are presented.

• Journal of Korean Society of Transportation
• /
• v.20 no.5
• /
• pp.153-161
• /
• 2002

다사용자계층 통행배정(Multiple User Class Assignment) 문제란 교통망을 이용하는 통행자들이 이질적인 통행계층으로 구성된 경우, 이들 각 계층의 통행수요를 교통망에 배정하는 문제를 의미한다. 이는 기존 통행 배정모형들이 모든 통행자의 통행특성이 동질적이라고 가정함으로서 발생하는 불합리한 통행배정 결과를 완화시키기 위한 방법이다. 또한, 최근 지능형교통체계(Intelligent Transportation Systems, ITS)사업에서 교통정보제공시스템이 구현될 예정임에 따라, 교통정보를 제공받는 계층과 그렇지 못한 계층간의 영향을 분석하거나 혼잡통행료부과 등과 같은 교통관리전략을 정확히 평가하기 위해서 다사용자계층 통행배정모형에 대한 관심이 증가하고 있다. 그러나, 다사용자계층 통행배정모형의 경우, 사용자간의 상호영향으로 통행비용함수의 1차 편미분행렬(Jacobian matrix)이 비대칭(Asymmetric)이 되어 동등 수리최소화문제(Equivalency mathematical Minimization program)로 구성할 수 없고 또한 수치적으로 풀기가 어렵다는 문제가 있다. 본 연구는 이런 문제점을 극복할 수 있는 모형식과 알고리듬을 제시코자 한다. 본 연구에서 제시된 모형은 2가지 특징이 있다. 먼저, 각 사용자 계층간의 상호영향을 모형내에 반영하며, 기종점쌍간의 통행시간변화에 따른 수요변화를 고려한다는 점이다. 이를 위하여 변동부등모형(Variational Inequality Model. VI)으로 문제를 구성하며, 이에 대한 해석 알고리듬도 제시한다. 또한, 변동부등모형으로 구축된 다사용자계층 모형이 다사용자계층 균형조건과 동일함을 보여주는 동등성조건(Equivalency condition)도 제시한다.

• Journal of Korean Society of Transportation
• /
• v.12 no.4
• /
• pp.65-88
• /
• 1994

교통수요와 공급은 상호 밀접한 연관성을 지니고 있다. 교통수요는 교통시설 서비 스수준 및 교통시설의 이용가격에 영향을 미치는 반면에 교통시설 공급비용과 서비스수준은 교통수요에 영향을 준다. 또한, 교통수요와 공급간의 상호작용은 도시공간상에서 발생하기 때문에 교통시스템의 공간적 구조 및 도시의 공간적 특성은 공급, 가격 및 수요를 통합한 교통균형모형에 있어서 매우 중요한 영향인자로 작용하게 된다. 그러나, 이제까지 개발된 교통균형모형에서는 통행인의 통행시간가치 및 교통체증의 도시공간상 변화가능성을 적절하 게 반영하지 못하고 있다. 본 연구에서는 도시공간상에서 통행인의 통행시간가치 변화패턴 을 반영한 수 도시공간상에서의 교통시설의 최적 서비스 수준, 교통수단별 최적요금체계를 도출할 수 있었다. 단핵도시구조를 지닌 도시공간상에서의 최적버스요금은 통행거리에 따라 할증되는 체계를 가져야 한다. 선행연구에서는 승용차에 대한 통행혼잡세 부과는 소득역분 배적인 효과를 초래하는 것으로 알려졌다. 그러나 버스의 요금구조나 서비스 수준이 최적수 준에서 제공된다면 통행혼잡세는 소득역분배적 결과를 초래하지 않는 것으로 나타났다.