• Korean Journal of Geomatics
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• v.4 no.2
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• pp.53-57
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• 2004

Due to the traffic congestion and public-oriented transportation policies of Seoul, public transportation is receiving attention and being used increasingly. However, current transport routes configuration is showing unbalanced accessibility throughout the city area creating differences in time, expenses and metal burden of users who travel the same distances. One of the reasons is that transport route planning has been partially empirical and non-quantitative tasks due to lack of relevant methods for assessing the complexity of the transport routes. This paper presents a method to compute the connectivity of public transport system based on the topological structure of the network of transport routes. The main methodological issue starts from the fact that the more transfers take place, the deeper the connectivity becomes making that area evaluated as less advantageous as for public transport accessibility. By computing the connectivity of each bus or subway station with all others in a city, we can quantify the differences in the serviceability of city areas based on the public transportation. This paper is based on the topological interpretation of the routes network and suggests an algorithm that can automate the computation process. The process is illustrated using a simple artificial network data built in a GIS.

• Journal of Korean Society of Transportation
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• v.28 no.1
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• pp.15-24
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• 2010

Until now, the location and the size of gate are designed by only experience and intuitive use judgement. However there are no studies that investigated how many people will be using each subway gate depending on the location of gates. Therefore, the purpose of this study is to develop a gate choice model of subway station. The most critical element of a gate choice in subway station is the location of pedestrian's destinations. In this study, the development of the regression model is constructed from data of land use characteristic of station vicinity and the number of bus route and the space structure of station vicinity(Depth concept by Space Syntax analysis and total road length of station vicinity) by using the real data of 30 subway station in Seoul. This study found that subway pedestrian flow are mainly determined by three factors; the total floor space of commercial buildings, Total Depth(space structure index of station vicinity), and the number of bus route. The verification of a proposed model is done by using the real gate pedestrian data of two subway station in Seoul; Gang-nam and Yang-jae. The additional study of how to define the gate impact area is analysed. Therefore, this study will provide the theoretical bases in decision of gate location and size when a new subway station is opened in future.

• Spatial Information Research
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• v.20 no.3
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• pp.83-93
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• 2012

Recent environmental concerns have made interest in environment-friendly transportation means such as walking, biking, and public transportation. However, since it is difficult to move long distance by walking or biking, their scope of application is rather limited. On the other hand, public transportation can solve traffic congestion, a recent social issue, though its usability may depend on its time schedule. Currently available information services on public transportation in the Web do not reflect well such traits of the public transportation; thus, in some cases, they may provide wrong information to end users. To solve such problems and provide information based on timetable of public transportations, this paper proposes a STP(Space Time Point) data model. Unlike existing space-time data models, this model recognizes the bottommost element of an object as a point and structures these points in hierarchical way to define an object. In particular, It can make it possible to implement a variety of dynamic spatial objects changing object information according to time. An objective of this study is to design a STP model for bus and subway based on timetables of public transportation in Daejeon area and builds a system to provide path navigation. With the designed navigation function, a path from the Daejeon National Cemetery to Hannam University was searched by time slot. The result showed that the system provided different paths by time, as the system guided different paths when bus operation was limited in midnight. As existing data model could not provide such results, it is confirmed that the system can provide path navigation based on real-time traffic information. It is expected that based on such functionality, it is possible to provide additional functionalities by applying diverse data models such as real-time transport information or traffic history information.

• Journal of Korean Society of Transportation
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• v.26 no.4
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• pp.205-215
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• 2008

As static traffic assignment has reached its limitation with ITS policy applications and due to the increase of interest in studies of ITS policies since the late 1980's, dynamic traffic assignment has been considered a tool to overcome such limitations. This study used the Dynameq program, which simulates route choice behavior by macroscopic modeling and dynamic network loading and traffic flow by microscopic modeling in consideration of the feasibility of the analysis of practical traffic policy. The essence of this study is to evaluate the feasibility for analysis in practical transportation policy of using the dynamic traffic assignment technique. The study involves the verification of the values estimated from the dynamic traffic assignment with South Korea's expressway network and dynamic O/D data by comparing results with observed link traffic volumes. This study used dynamic O/D data between each toll booth, which can be accurately obtained from the highway Toll Collection System. Then, as an example of its application, exclusive bus-lane policies were analyzed with the dynamic traffic assignment model while considering hourly variations.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.2
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• pp.1-12
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• 2017

The Seoul metropolitan transportation card's high value lies in its recording of total population movements of the public transit system. In case of recorded information on transit by bus, even though route information utilized by each passenger is accurate, the lack of passenger transfer information of the urban railway makes it difficult to estimate correct routes taken by each passenger. Therefore, pinpointing passenger path selection patterns arising in the metropolitan railway network and using this as part of a path movement estimation model is essential. This research seeks to determine that features of passenger movement routes in the urban railway system is comprised of M-similar routes with increasing number of transfer reflected as additional costs. In order to construct the path finding conditions, an M-similar route searching method is proposed, embedded with non additive path cost which appears through inclusion of the stepwise transportation parameter. As well, sensitivity of the M-similar route method based on transportation card records is evaluated and a stochastic trip assignment model using M-similar path finding is constructed. From these, link trip and transfer trip results between lines of the Seoul metropolitan railway are presented.

• Journal of Korea Spatial Information System Society
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• v.9 no.3
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• pp.25-33
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• 2007

The local governments of major cities in Korea are giving focus on public transportation to reduce congestion and improve accessibility in city areas. In this regards, the proper measurement of accessibility is now a key policy requirement for reorganizing the public transport network. Public transport routing problems, however, are considered to be highly complicated since a multi-mode travel generates different combinations of accessibility. While most of the previous research efforts on measuring transport accessibility are found at zone-levels, an alternative approach at a finer scale such as bus links and stops is presented in this study. We proposes a method to compute the optimal route choice of origin-destination pairs and measure the accessibility of the chosen modes combination based on topological configuration. The genetic algorithm is used for the computation of the journey paths, whereas the space syntax theory is used for the accessibility. This study used node-link data in GIS instead of axial lines which are manually drawn in space syntax. The resulting accessibilities of bus stops are calibrated by O-D survey data and the proposed process is tested on a CBD of Seoul.

• The Korean Journal of Applied Statistics
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• v.26 no.4
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• pp.623-634
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• 2013

In this study, we provide empirical evidence of whether a spatial correlation among mode choices at the TAZ(Traffic Analysis Zone) level exists based on transit smart card data observed in Seoul, Korea. The results show that the areas with a higher probability that passengers choose to take a bus are clustered and that those regions have fewer metro stations than bus stations. We also found that the spatial correlation turned out to be statistically meaningful and provided an opportunity for the potential use of the spatial correlation in modeling mode choices. A reliable spatial interaction would constitute valuable information for transportation agencies in terms of their route planning and scheduling based on the transit smart card data.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.11A
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• pp.912-923
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• 2011

In this paper, we propose a routing protocol for WMNs to provide passengers in public transportation vehicles (e.g., bus and tram) with Internet access service. In order to support end users with a reliable Internet connection despite the mobility of vehicles, we assume that mesh router, called mobile mesh router (MMR), is installed in a vehicle and manages a route to Internet Gateway (IGW). We therefore propose an efficient routing protocol and its routing metric, called ETT-TR, considering trajectory information of vehicle as well as link quality in order to find a route between them. Using NS-2 simulations, we observe that our proposed routing protocol reduces the end-to-end delay and improves throughput performance.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.5
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• pp.520-529
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• 2002

Though BIFS is a complex description language that represents MPEG-4 content as text or bit streams, most traditional MPEG-4 content authoring tools are developed for a BIFS expert. Before using these tools, many authors must invest much time and energy in acquiring knowledge of BIFS. In this paper, we suggest a new manner for saving these efforts. Our proposal supplies the convenient user interface of traditional multimedia authoring tools for MPEG-4 authors and interprets the authored information and transforms it into BIFS. In our user interface, the author generates the minimal authoring information requested for generating BIFS; the BIFS generation module then transforms the information into BIFS format using predefined BIFS construction rules. The resulting BIFS consists of the Scene Tree and the Object Descriptor and Route; they are used for constructing MP4 standard files by mixing with the Elementary Stream.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.12
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• pp.1969-1977
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• 2016

We study the connection time of vehicle-to-mobile roadside unit (V2MR) communications which can reduce the significant cost of the fixed RSU by installing a gateway of mobile network into a transit bus called the mobile RSU. In the V2MR communications, the connectivity of a commute vehicle can be improved via ad-hoc connection to a nearby mobile RSU. In this paper, we present a new analysis model to estimate the connection time between a commute vehicle and a mobile RSU, when there is a bus station in the overlapping route. Since the connection time between two vehicles is highly dynamic and unpredictable, our analysis will provide a fundamental basis of connection-time estimation of V2MR communications. Numerical results obtained from VEINS simulation show that our analysis can estimate the connection time of V2MR communications with the average error below 1.0 percent. Moreover, we show that the average connection time of V2MR communications can be extended to approximately 3.85 times of that of V2R communications.