• Proceedings of the KOR-KST Conference
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• 2000.02a
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• pp.3-22
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• 2000

이용자의 경로선택 형태를 모사하는 통행배정모형 결과의 정확도는 교통계획에 상당한 영향을 미친다. 이용자의 경로선택 결정과정에서 가장 중요한 판단기준은 통행시간과 통행요금이다. 그런데 통행요금은 이용자의 경로거리에 따라 다양한 방식으로 부과되므로, 링크를 분석단위로 하는 기존의 통행배정모형은 현실적인 통행요금 반영이 힘들었고 또한 수요예측 결과를 이용한 다양한 분석에서 제약을 받아 왔다. 본 연구는 이러한 배경에서 경로교통량을 도출할 수 있는 경로기반 통행배정모형을 구축하였고, 또한 경로거리에 따라 결정되는 현실적인 통행요금을 반영할 수 있는 알고리즘을 개발하였다. 경로기반 배정모형에서는 GP(Gradient Projection) 알고리즘을 이용하였고, 계산상의 효율성 제고를 위해 K-최단경로 알고리즘 중 MPS(Minimal Path Search) 알고리즘을 이용하였다. 개발된 배정 모형은 현실적인 통행요금을 반영할 수 있으므로 통행배정 결과의 정밀도를 향상시켰을 뿐만 아니라 기존 배정모형에 비해 최적해로의 수렴속도도 개선되는 것으로 나타났다. 본 논문의 배정모형은 경로교통량이 도출되고 통행요금을 반영할 수 있으므로, 통행요금과 통행 거리 관계에 따른 목적함수의 규명과 그에 따른 효과척도를 계량화할 수 있다. 따라서 본 모형은 통행배정에서 실재상황을 보다 현실여건에 맞도록 규명할 수 있고, 기존의 제한적인 효과분석의 문제점을 해결할 수 있으므로 그 활용범위가 넓다. 또한 본 논문은 개발된 배정모형의 적용사례로서 고속도로 수요관리 요금체계 개선방안을 제시하였다. 기존의 고속도로 통행요금 산정 방법은 이론적 근거가 미약했던 반면, 본 논문에서 개발된 배정모형과 고속도로 수요관리 요금체계 개선방안은 고속도로 통행료 결정에 대한 과학적이고 합리적인 분석방법을 제공하였다.한 민감도 분석을 실시한 결과 대안1의 경우 교통량의 변화 및 화물통행의 시간가치의 증가시 사회적 편익이 오히려 감소하였고, 대안2와 3의 경우 사회적 편익이 증가하는 것을 알 수 있었다. 이는 경부고속도로의 화물차량의 구성비에 따라 대안 1의 경우 오히려 화물차의 통행시간이 증가함에 그 원인이 있다 할 것이다. 이상과 같은 결론을 통하여 경부고속도로상의 화물전용차선의 설치시는 수답렬 교통량의 구성비와 구간 평균교통량에 의하여 그 효과가 다르게 나타남을 알 수 있었다. 따라서 물류비용 절감차원에서의 화물전용차선의 설치는 본 연구에서 나타낸 방법과 같이 수단간의 경제적 편익을 고려한 구간별 시간대별 효과분석을 통하여 정책의 시행여부가 결정되어야 할 것이다. 한편, 화물전용차선의 설치로 인한 물류비용의 절감을 보다 효과적으로 달성하기 위해서는 종합류류 전산망의 시급한 구축과 함께 화물차의 적재율을 높이고 공차율을 낮출 수 있는 운송체계의 수립이 필요한 것으로 판단된다. 그라나 이러한 화물전용차선의 효과는 단기적인 치유책일 수밖에 없기 때문에 물류유통 시설의 확충을 위한 사회간접자본의 구축을 서둘러 시행하여야 할 것이다.으로 처리한 Machine oil, Phenthoate EC 및 Trichlorfon WP는 비교적 약효가 낮았다.>$^{\circ}$E/$\leq$30$^{\circ}$NW 단열군이 연구지역 내에서 지하수 유동성이 가장 높은 단열군으로 추정된다. 이러한 사실은 3개 시추공을 대상으로 실시한 시추공 내 물리검층과 정압주입시험에서도 확인된다.. It was resulted from increase of weight of single cocoon. "Manta"2.5ppm produced 22.2kg of co

• Journal of the Korean Society for Railway
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• v.14 no.3
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• pp.276-284
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• 2011

In our study, we present a new LOGIT-based traffic assignment model applicable to intercity railway network. Most traffic assignment models have been developed for public transit assignment in urban area, so that they are known to produce unrealistic results in intercity railway demand analysis. Especially, since the introduction of KTX, more passengers are using a route including KTX service and the schedule becomes more compatible with transfer. Our study presents a new LOGIT-based traffic assignment model considering passenger transfer. To do so, we suggest a new route search algorithm to find K paths with non increasing order in the utility value.

• Journal of Korean Society of Transportation
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• v.30 no.6
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• pp.47-57
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• 2012

The purpose of this study is to propose a supplement to current freight demand model by analyzing factors that influence the generation of empty truck movements in regional and urban realms. To achieve this, we examined the relation between the number of empty truck trips and various generators such as truck attributes, origin type and attributes, destination type and attributes, and commodity type. We structured the ordered logit model using 2011 Korea Transport Database (KTDB) data to analyze the generator characteristic of empty truck movements in regional and urban settings. According to the results, the characteristics of regional and urban empty truck movements differed depending on truck attributes, origin type and attributes, destination type and attributes, and commodity type.

• 한국공간정보시스템학회:학술대회논문집
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• 2005.05a
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• pp.9-14
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• 2005

교통정책과 계획수립에 가장 중요한 의사결정 과정은 통행수요 분석이고, 이에 활용되고 있는 필수적인 기초 데이터베이스는 분석용 네트워크와 기종점 통행량이 있다. 통행수요 추정과정의 합리성이 보장되도록 하기 위해서는 이러한 기본 입력 자료의 신뢰성은 중요하다. 하지만, 일반적으로 분석용 네트워크를 구축할 때 예산과 분석기간의 제약 때문에 실세계의 교통망 중 많은 부분을 단순화 시켜서 구축한다. 또한 기 구축된 네트워크에 대해서도 변경되는 교통망을 반영하기 위해 네트워크를 수정, 편집할 때에도 많은 재원과 시간이 소요된다. 본 연구에서는 이러한 문제점을 보완하고자 교통분석 목적의 패키지(EMME/2, TranPlan) 혹은 범용의 GIS 패키지(ArcGIS)에서 직접 이용할 수 있도록 기 구축된 네트워크를 기반으로 GIS 데이터로의 변환 혹은 네트워크를 추출하는 양방향 데이터 교환 시스템을 개발하였다. 이러한 GIS-T 통합 시스템은 네트워크의 편집과 분석에 효율적인 환경을 제공하여 보다 현실적인 교통망 모델링을 반영할 것으로 기대되며 다양한 교통문제에 대한 분석에 효과적인 도구로 활용될 수 있을 것이다.

• Journal of Korean Society of Transportation
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• v.26 no.5
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• pp.227-235
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• 2008

This study analyzed the efficiency of a trunk with branches and a trunk with feeders route system comparing the user cost and operator cost of those route systems. Basically, a trunk with branches is more efficient than a trunk with feeders in the passengers' perspective if the transit system of a trunk and feeders are the same. In the case that the trunk system is hierarchically higher than the feeder system, a trunk with feeders has the competitive edge over a trunk with branches if the saving of travel cost induced by using the trunk line is larger than the increasing waiting and transfer cost. This result is consistent with the previous research by Park et al.(2007c), which analyzed the efficiency of hierarchical structure in a grid transit network. If the travel demand of each origins and destinations is low, increasing headway according to the travel demand can increase passenger load or operating efficiency in a trunk with feeders route system. In this case, a trunk with feeders route system is more prevalent as the operating cost, route length, and number of destinations increases, while it is less prevalent as the transfer cost and passengers' time value of the waiting time increases. In cases that central business district, which is located in the middle of a trunk line, generates travel demand, a trunk with feeders is more efficient than a trunk with branches with the increasing travel demand from and to the CBD. Therefore it can be concluded that to have a dual operating system between CBD and suburban is more efficient than one type transit system. The efficiency of that system can be increased through an efficient transfer system that can reduce the transfer cost.

• Journal of Korean Society of Transportation
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• v.23 no.2
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• pp.25-36
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• 2005

In this study, we suggested a new approach method forecasting distribution demand of urban rail transit usign fuzzy control, with intend to reflect irregularity and various functional relationship between trip length and distribution demand. To establish fuzzy control model and test this model, the actual trip volume(production, attraction and distribution volume) and trip length (space distance between a departure and arrival station) of Daegu subway line 1 were used. Firstly, usign these data we established a fuzzy control model, nd the estimation accuracy of the model was examined and compared with that of generalized gravity model. The results showed that the fuzzy control model was superior to gravity model in accuracy of estimation. Therefore, wwe found that fuzzy control was able to be applied as a effective method to predict the distribution demand of urban rail transit. Finally, to increase the estimation precision of the model, we expect studies that define membership functions and set up fuzzy rules organized with neural networks.

• Journal of Korean Society of Transportation
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• v.17 no.2
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• pp.137-147
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• 1999

This paper studies on the optimal bus network design in the framework of the set covering theory. The theory enables to cover passenger's loading and alighting areas as the set, and maximize the covering set as much as possible. In other words, it calculates the minimal set of the bus routes for covering whole bus passengers demand. After the optimal set of the bus routes is generated by the set covering theory, multimodal traffic equilibrium assignment is used for evaluating the generated set in terms of passenger's mode and route choice behavior. Whilst most previous works on it have been based on analyzing a specific route in a limited area, this study seeks to optimize the whole bus network.

• Journal of Korean Society of Transportation
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• v.24 no.2 s.88
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• pp.169-178
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• 2006

Traffic assignment has been used both for predicting travel demands and for evaluating the tools for alleviating congestion on road network in advance. Some assignment models have been proposed such as equivalent mathematical minimization method, variational inequality problem, nonlinear complementary problem and fixed point method, in following the principle of Wardrop (1952) that no driver can not Improve his travel cost by unilaterally changing his route. Recently Jin(2005a) presented a traffic assignment model based on dynamic process. This paper proposes a solution algorithm for the model of Jin and assesses the performances. Compared to the Frank-Wolfe method, which has been wildly used for solving the existing assignment models, the proposed algorithm is expected to be more efficient because it does not need to evaluate the objective function. Two numerical examples are used for assessing the algorithm, and they show that the algorithm converges to user equilibrium of Wardrop.

• Journal of Korean Society of Transportation
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• v.30 no.4
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• pp.85-94
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• 2012

Modern freight transport pursues not only the reduction of logistic costs but also aims at green logistics and efficient shipments. In order to accomplish these goals, various policies regarding the multimodal shipment and stopover to logistic facilities have widely been made. Such situation requires changes in existing methods for analyzing freight demand. However, the reality is that a reliable freight demand forecast is limited, since in the transport research field there is no robust freight demand model that can accommodate transshipments at logistic facilities. This study suggested a novel method to analyze freight demand, which can consider transshipments in multi-modal networks. Also, the applicability of this method was discussed through an example test.

• 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.