• Proceedings of the KSR Conference
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• 2010.06a
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• pp.769-774
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• 2010

KTX Introduced in korea have occurred enhanced services and reduced regional travel time. "Induced traffic" is defined in the traffic demand generated in new project. 'Induced traffic' compared to the Diversion Demand Survey and research on ways to quantify the situation, insufficient analysis of constant and long-term observations are needed to estimate the changes in demand. In this study, Induced traffic effects due to the opening of KTX for analysis survey to passengers by Railway and the scale factor induced traffic review.

• International Journal of Highway Engineering
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• v.10 no.3
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• pp.139-147
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• 2008

8 Exclusive Median Bus Lanes(EMBL) are operated in Seoul metropolitan city after the opening of Chon-ho section in 1996. But the changes in the road traffic demand on the direct and indirect influence area have not reported. In this paper, before and after survey and analysis of road traffic demand on 3 EMBLs opened in 2004 are conducted. In summary, the traffic demand of 3 EMBL road section decreased dramatically to 24.7% after the opening and then increased 1.4% after a year. The traffic demand of detour road decreased to 2.9% after the opening and then increased 0.3% after a year. Considering measurement error as ${\pm}5%$, Road traffic demands on the influence area of EMBL section are a stable state after one year. So it is presumed that the trip demand on EMBL section using vehicle does not make a detour around the influence area but divert into another transport modal.

• Journal of ILASS-Korea
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• v.21 no.4
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• pp.214-222
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• 2016

Changes in road infrastructure affect driving patterns and pollutant emission characteristics. we analyzed the changes in driving patterns and pollutant emission characteristics of the driving route via measured driving patterns at year 2009 and 2016. Since 2009, there has been an increase in population and traffic demand, including residential areas and industrial facilities. Traffic conditions were improved such as the opening of the highway Inter-Change to Seoul and the construction of underground driveway. As a result, the average vehicle speed increased. More detail comparisons have made on the changes of the underground driveway section and the crossroad section, which are expected to have significant changes in the transportation infrastructure. The vehicle speed distribution of the underground driveway changed from low speed to high speed, and the increase of the time spent at the high speed and high load caused the increase of NOx emissions. The vehicle speed also increased at the crossroad section, and the consequence NOx and $CO_2$ emissions decreased. It is mainly because the decreased time spent at idle, which results from the proper traffic demand management at this area.

• Journal of Computational Design and Engineering
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• v.1 no.4
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• pp.233-242
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• 2014

A magnetically levitated vehicle (Maglev) system is under commercialization as a new transportation system in Korea. The Maglev is operated by an unmanned automatic control system. Therefore, the plan of train operation should be carefully established and validated in advance. In general, when making a train operation plan, statistically predicted traffic data is used. However, a traffic wave often occurs in real train service, and demand-driven simulation technology is required to review a train operation plan and service quality considering traffic waves. We propose a method and model to simulate Maglev operation considering continuous demand changes. For this purpose, we employed a discrete event model that is suitable for modeling the behavior of railway passenger transportation. We modeled the system hierarchically using discrete event system specification (DEVS) formalism. In addition, through implementation and an experiment using the DEVSim++ simulation environment, we tested the feasibility of the proposed model. Our experimental results also verified that our demand-driven simulation technology can be used for a priori review of train operation plans and strategies.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.5
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• pp.922-931
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• 2012

This paper studies a series of logical topology reconfiguration processes corresponding to a series of traffic demand changes in a ship backbone network. The proposed reconfiguration technique is to minimize costly changes of traffic forwarding paths and minimize the average hop distance of traffic forwarding paths in terms of ship backbone network performance simultaneously. Performance evaluation is conducted to illustrate the efficiency of the proposed reconfiguration technique. It shows that the proposed reconfiguration technique yields efficient performance in the entire series of reconfiguration processes.

• Spatial Information Research
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• v.20 no.5
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• pp.37-47
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• 2012

This study analyzes the changes of lifestyle and urban spaces with the advent of U-City and tries to propose a direction of urban policies reflecting them. For this, it investigates lifestyle changes to predict the phase of urban spaces in the future. In a survey on urban functionalities with downtown as the main space of activities, it was expected that traffic for the use of these functionalities would be reduced. Traffic reduction was predicted to restrain downtown from growing and weaken the concentration of downtown activity. For the reorganization of existing spaces, in particular, public spaces would be changed to multi-purpose spaces in which various urban activities can be carried out using ubiquitous technologies. With the advent of U-City and the various changes of conditions, it is expected that the demand for land use and urban planning facilities would be altered by downtown and peripheries. A planning tool with a more concrete demand estimation of the future demand in individual areas of usage should be developed and it should be reflected in urban planning. Also, with the integration of functionalities so that more efficient land use will be possible, flexible designation of usage areas is necessary. Along with this, to prevent the decline of old downtown areas and provincial cities, the balanced installation of IT-related infrastructures will precede.

• Journal of Korean Society of Transportation
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• v.28 no.5
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• pp.107-116
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• 2010

The vehicle travel time between locations in a downtown is greatly influenced by both complex road conditions and traffic situation that changes real time according to various external variables. The customer's demands also stochastically change by time period. Most vehicle routing problems suggest a vehicle route considering travel distance, average vehicle speed, and deterministic demand; however, they do not consider the dynamic external environment, including items such as traffic conditions and stochastic demand. A realistic vehicle routing problem which considers traffic (smooth, delaying, and stagnating) and stochastic demands is suggested in this study. A mathematical programming model and hybrid genetic algorithm are suggested to minimize the total travel time. By comparing the results considering traffic and stochastic demands, the suggested algorithm gives a better solution than existing algorithms.

• Journal of the Korea Society for Simulation
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• v.20 no.3
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• pp.89-100
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• 2011

The MAGLEV (Magnetically Levitated Vehicle) system, which is under commercialization as a new transportation system in Korea, is operated by means of unmanned automatic control system. Therefore the plan of train operation should be carefully established and validated in advance. In general, when making the train operation plan, the statistically predicted traffic data is used. However, traffic wave can occur when real train service is operated, and the demand-driven simulation technology is required to review train operation plans and service qualities considering traffic wave. This paper presents a method and model to simulate the MAGLEV's operation considering continuous demand changes. For this purpose, we employed the discrete event model which is suitable for modeling the behavior of railway passenger transportation, and modeled the system hierarchically using DEVS (Discrete Event System Specification) formalism. In addition, through the implementation and experiment using DEVSim++ simulation environment, we tested the feasibility of the proposed model and it is also verified that our demand-driven simulation technology could be used for the prior review of the train operation plans and strategies.

• Journal of Korean Society of Transportation
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• v.11 no.1
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• pp.67-86
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• 1993

A formulation of dynamic traffic assignment between multiple origins and single destination was first introduced in 1987 by Merchant and Nemhauser, and then expanded for multiple destination in the late 1980's (Carey, 1987). Based on behavioral choice theory which provides proper demand elasticities with respect to changes in policy variables, traffic phenomena can be analysed more realistically, especially in peak periods. However, algorithms for these models are not well developed so far(working with only small toy network) and solutions of these models are not unique. In this paper, a new model is developed which keeps the simplicity of static models, but provides the sensitivity of dynamic models with changes of O-D flows over time. It can be viewed as a joint departure time and route choice model, in the given time periods(6-7, 7-8, 8-9 and 9-10 am). Standard multinomial logit model has been used for simulating the choice behavior of destination, mode, route and departure time within a framework of the incremental network assignment model. The model developed is workable in a PC 386 with 175 traffic zones and 3581 links of Seoul and tested for evaluating the exclusive use of Namsan tunnel for HOV and the left-turn prohibition. Model's performance results and their statistical significance are also presented.

• Journal of Korean Institute of Industrial Engineers
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• v.29 no.2
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• pp.135-144
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• 2003

Traffic performance in a microcellular system is much more affected by cell dwell time and channel holding time in each cell. Cell dwell time of a call is characterized by its mobility pattern, i.e., stochastic changes of moving speed and direction. Cell dwell time provides important information for other analyses on traffic performance such as channel holding time, handover rate, and the average number of handovers per call. In the next generation mobile communication system, the cell size is expected to be much smaller than that of current one to accommodate the increase of user demand and to achieve high bandwidth utilization. As the cell size gets small, traffic performance is much more affected by variable mobility of users, especially by that of pedestrians. In previous work, analytical models are based on simple probability models. They provide sufficient accuracy in a simple second-generation cellular system. However, the role of them is becoming invalid in a picocellular environment where there are rapid change of network traffic conditions and highly random mobility of pedestrians. Unlike in previous work, we propose an improved probability model evolved from so-called Random walk model in order to mathematically formulate variable mobility of pedestrians and analyze the traffic performance. With our model, we can figure out variable characteristics of pedestrian mobility with stochastic correlation. The above-mentioned traffic performance measures are analyzed using our model.