• Journal of Korean Society of Transportation
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• v.27 no.5
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• pp.195-208
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• 2009

A network design problem (NDP) formulated as a mathematical program is generally used to find an optimum value to minimize or to maximize some objectives such as total travel time, social benefit, or others. NDP has, however, some limits of describing components of travel patterns like activities and trip generation due to its modeling simplicity, and also it has difficulty in including attributes of regional planning. In order to cope with such limits, this paper extends NDP to the urban planning field and proposes a mathematical program which can describe the interactions between urban social activities and transportation planning. Based on this model the authors try to optimize both urban activities and the transportation system. The model developed in this paper is tested to assess its application with a real-size regional transportation network.

• Journal of the Korean Society for Railway
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• v.15 no.2
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• pp.185-192
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• 2012

Line planning is to determine the frequency of trains on each line to satisfy origin-destination demand while minimizing total operation cost. However, different from the line planning in passenger transportation, it is more important at which intermediate stations each train should be stopped and shunted because the freight car handling works like drop-off or(and) pick-up can incur much time and high cost so that the delay deteriorates the quality of rail freight transportation service. We present an optimization model for constructing line plan in rail freight transportation to simultaneously minimize the train operation cost and total transportation time of freights. And we suggest a column generation approach for our problem, which can solve the real network instances in reasonable computation times.

• 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.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2009.06a
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• pp.165-166
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• 2009

The purpose of this study is to develop a model of the optimal stowing plan for car carriers. This model will be used for an integrated model of maritime transportation planning for car carriers with vessel allocation and voyage planning models.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.4 no.2 s.7
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• pp.45-52
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• 2005

Sketch-Planning based ITS Deployment Analysis System is an analysis tool for determining the impacts, benefits, and costs of various intelligent transportation system (ITS) deployments. This methodology offers one tool that systematically assesses ITS scenarios to facilitate the integration of such scenarios into the ongoing transportation planning process. Sketch-planting based methodology can estimate relative impacts, benefits, and costs for more than 60 types of ITS investments deployed in isolation or in any combination defined by the user.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.27 no.2
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• pp.102-113
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• 2004

This paper addresses the transportation planning that is based on genetic algorithm for determining transportation time and transportation amount of minimizing cost of distribution system. The vehicle routing of minimizing the transportation distance of vehicle is determined. A distribution system is consisted of a distribution center and many retailers. The model is assumed that the time horizon is discrete and finite, and the demand of retailers is dynamic and deterministic. Products are transported from distribution center to retailers according to transportation planning. Cost factors are the transportation cost and the inventory cost, which transportation cost is proportional to transportation distance of vehicle when products are transported from distribution center to retailers, and inventory cost is proportional to inventory amounts of retailers. Transportation time to retailers is represented as a genetic string. The encoding of the solutions into binary strings is presented, as well as the genetic operators used by the algorithm. A mathematical model is developed. Genetic algorithm procedure is suggested, and a illustrative example is shown to explain the procedure.

• Journal of Korean Society of Transportation
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• v.30 no.2
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• pp.117-126
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• 2012

The transportation sector accounts for 33% of the total $CO_2$ emissions. Effective control measures for reducing $CO_2$ emissions are urgently needed to address global warming. Objective and reliable methods to estimate $CO_2$ emissions are a prerequisite for the implementation of such effective control measures. However, existing models have not been successful. Even though the average-speed model is one of the most convenient and useful methods for estimating $CO_2$ emissions, it cannot distinguish between a variety of roads as well as traffic conditions in the model. The results of this study found that there may be significant discrepancies between emissions estimated by the current average-speed model and those measured in real driving conditions. This paper proposed the subdivision of emission factors in the average-speed model depending on both traffic and road conditions.

• Korean Management Science Review
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• v.28 no.3
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• pp.1-13
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• 2011

Hub-and-spoke transportation network is a powerful and useful network structure that takes full advantage of economies of scale on routes between hubs. In recent studies, the network structure is extended to hybrid hub-andspoke that allows direct transportation between spokes. In this study, we considered more extended network structure which is called hybrid multiple hub-and-spoke that has multiple hubs and allows direct transportation between spokes. We developed a mathematical optimization model for automotive service parts transportation planning under hybrid multiple hub-and-spoke network structure. The model suggests a long-term transportation route planning and a short-term vehicle assignment planning. The model is verified by simulation and validated in real world application to Hyundai Mobis automotive service parts transportation planning. From the simulation result, the model reduced the transportation cost about 24.7%, the total distance about 6.8% and the CO2 emissions about 8.8%. In real world application for 6 months from July to December 2010, the model reduced the transportation cost about 9.1% by changing the long-term transportation route without daily vehicle assignment planning.

• Journal of Korean Society for Geospatial Information Science
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• v.1 no.1 s.1
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• pp.127-140
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• 1993

The purpose of this paper is to examine the possible benefits of combining transportation planning models with geographic information systems (GIS) in the hope that intergrating these systems can alleviate the inherent problems of transportation planning models such as user unfriendliness, labor intensiveness, and theoretical limitations. Specially, this paper focuses on the issue of incompatiblity between GIS and the conventional transportation planning models in dealing with network topologies. Resolving this conflict in topologies is a conerstone for eliminating the user-unfriendliness and labor-intensiveness issues. This paper presents the development of an algorithm that converts GIS topology into transportation network topology. The FORTRAN-based topology conversion algorithm generates transportation networks from the GIS cartographic file and establishes a communication charmel between the two systems.

• Journal of Korean Society for Geospatial Information Science
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• v.1 no.2 s.2
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• pp.105-112
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• 1993

The conventional method for solving transportation problems were mainly based on numerical methods, where the understanding of outputs is not easy. Some difficulties come from the seperation of three key steps-the preparation of input for transportation traffic simulation, and model output interpretation. GSIS can help to eliminate some of thoses difficulties by combining graphics, database, and transportation plaining models. As pilot study, this study shows an application of Geovision GSIS to TRANPLAN transportation planning model that is based on four-step travel demand forecasting procedure. Accrued benefits and procedure are presented.