• International Journal of Highway Engineering
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• v.18 no.1
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• pp.99-107
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• 2016

PURPOSES : This study was initiated to estimate expressway traffic congestion costs by using Vehicle Detection System (VDS) data. METHODS : The overall methodology for estimating expressway traffic congestion costs is based on the methodology used in a study conducted by a study team from the Korea Transport Institute (KOTI). However, this study uses VDS data, including conzone speeds and volumes, instead of the volume delay function for estimating travel times. RESULTS : The expressway traffic congestion costs estimated in this study are generally lower than those observed in KOTI's method. The expressway lines that ranked highest for traffic congestion costs are the Seoul Ring Expressway, Gyeongbu Expressway, and the Youngdong Expressway. Those lines account for 64.54% of the entire expressway traffic congestion costs. In addition, this study estimates the daily traffic congestion costs. The traffic congestion cost on Saturdays is the highest. CONCLUSIONS : This study can be thought of as a new trial to estimate expressway traffic congestion costs by using actual traffic data collected from an entire expressway system in order to overcome the limitations of associated studies. In the future, the methodology for estimating traffic congestion cost is expected to be improved by utilizing associated big-data gathered from other ITS facilities and car navigation systems.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.4
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• pp.487-497
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• 2015

Using existing tunnel for section enlargement and remodeling is being considered as an optimal alternative in order to solve traffic jam in tunnel. The existing method has been performed while blocking the traffic flow. Recently, New enlargement method was developed which can maintain traffic flow during the construction by using protector. It can minimize social loss due to keeping traffic flow. On the other hand, installing and operating protector can cause economic disadvantages. So, social cost estimation considering traffic flow should be considered for relevant economic evaluation of tunnel section enlargement methods. This paper presents the social cost estimation method of tunnel section enlargement methods considering traffic flow. In addition, to compare economic efficiency existing method with new method, suggested method was applied to Maebong Tunnel.

• International Journal of Highway Engineering
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• v.18 no.3
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• pp.47-57
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• 2016

PURPOSES : This study aims to examine the differences between the existing traffic demand forecasting method and the traffic demand forecasting method considering future regional development plans and new road construction and expansion plans using a four-step traffic demand forecast for a more objective and sophisticated national highway maintenance. This study ultimately aims to present future pavement deterioration and budget forecasting planning based on the examination. METHODS : This study used the latest data offered by the Korea Transport Data Base (KTDB) as the basic data for demand forecast. The analysis scope was set using the Daejeon Metropolitan City's O/D and network data. This study used a traffic demand program called TransCad, and performed a traffic assignment by vehicle type through the application of a user equilibrium-based multi-class assignment technique. This study forecasted future traffic demand by verifying whether or not a realistic traffic pattern was expressed similarly by undertaking a calibration process. This study performed a life cycle cost analysis based on traffic using the forecasted future demand or existing past pattern, or by assuming the constant traffic demand. The maintenance criteria were decided according to equivalent single axle loads (ESAL). The maintenance period in the concerned section was calculated in this study. This study also computed the maintenance costs using a construction method by applying the maintenance criteria considering the ESAL. The road user costs were calculated by using the user cost calculation logic applied to the Korean Pavement Management System, which is the existing study outcome. RESULTS : This study ascertained that the increase and decrease of traffic occurred in the concerned section according to the future development plans. Furthermore, there were differences from demand forecasting that did not consider the development plans. Realistic and accurate demand forecasting supported an optimized decision making that efficiently assigns maintenance costs, and can be used as very important basic information for maintenance decision making. CONCLUSIONS : Therefore, decision making for a more efficient and sophisticated road management than the method assuming future traffic can be expected to be the same as the existing pattern or steady traffic demand. The reflection of a reliable forecasting of the future traffic demand to life cycle cost analysis (LCCA) can be a very vital factor because many studies are generally performed without considering the future traffic demand or with an analysis through setting a scenario upon LCCA within a pavement management system.

• Journal of Navigation and Port Research
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• v.31 no.10
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• pp.819-824
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• 2007

This paper studied safety benefit of operation-effectiveness analysis on marine traffic safety facilities. In the operation-effectiveness of marine traffic safety facilities the benefits can be divided as safety benefit, transport benefit, and other benefit. Safety benefit was produced as the loss aversion cost of marine traffic caused by the reduction of marine accidents after establishing and operating marine traffic safety facilities. First of all the reduction rate marine accidents was estimated to do it, and the detail model of loss aversion cost was constructed Then each variable in the model was defined and the method of computation presented.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.4
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• pp.45-51
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• 2009

The paper presents the economic analysis of optimized-rehabilitation area method considered as one of the preventive maintenance methods in asphalt concrete pavement. The optimized-rehabilitation area was selected based on the analysis of traffic lane characteristics. The main concept of the selected method was to minimize the maintenance cost. The effective width of traffic lane in this method was 70 cm of each wheel path. According to the traffic survey conducted in this research, more than 95% of vehicles passed within the width of each wheel path. The new preventive optimized-rehabilitation area method showed less maintenance cost than the conventional overlay. In addition, traffic congestions and the user cost can be reduced. The research results revealed that the total maintenance cost was reduced by 35% by using the new method compare to the conventional one.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5D
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• pp.649-654
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• 2008

In the definition of non additive path, the sum of travel costs of links making up the path is not equal to the path cost. There are a variety of cases that non-additivity assumption does not hold in transportation fields. Nonetheless, traffic equilibrium models are generally built up on the fundamental hypothesis of additivity assumption. In this case traffic equilibrium models are only applicable within restrictive conditions of the path cost being linear functions of link cost. Area-wide road pricing is known as an example of realistic transportation situations, which violates such additivity assumption. Because travel fare is charged at the moment of driver's passing by exit gate while identified at entry gate, it may not be added linearly proportional to link costs. This research proposes a novel Wordrop type of traffic equilibrium model in terms of area-wide road pricing schemes. It introduces binary indicator variable for the sake of transforming non-additive path cost to additive. Since conventional shortest path and Frank-Wolfe algorithm can be applied without route enumeration and network representation is not required, it can be recognized more generalized model compared to the pre-proposed approaches. Theoretical proofs and case studies are demonstrated.

• Journal of Korean Society of Transportation
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• v.17 no.4
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• pp.71-84
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• 1999

The purpose of this study is to construct a dynamic traffic analysis model using the existing traffic flow theory in order to develope a dynamic traffic assignment technique. In this study the dynamic traffic analysis model was constructed using Daganzo's CELL TRANSMISSION THEORY which was considered more suitable to dynamic traffic assignment than the other traffic flow theories. We developed newly the diverging split module, the cost update module and the link cost function and defined the maximum waiting time decision function that Daganzo haven't defined certainly at his Papers. The output that resulted from the simulation of the dynamic traffic analysis model with test network I and II was shown at some tables and figures, and the analysis of the bottleneck and the HOV lane theory showed realistic outputs. Especially, the result of traffic assignment using the model doesn't show equilibrium status every time slice but showed that the average travel cost of every path maintains similarly in every time slice. It is considered that this model can be used at the highway operation and the analysis of traffic characteristics at a diverging section and the analysis of the HOV lane effect.

• International Journal of Highway Engineering
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• v.15 no.2
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• pp.149-157
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• 2013

PURPOSES : This study is to analysis for benefit and construction cost in underpass for small vehicles. METHODS : The study was performed using the traffic software VISSIM 5.20 for analysis on a variety of traffic conditions and analysed of benefits of changes through analysis of travel speed and travel time after modeling of existing underpass and small vehicle underpass. RESULTS : Results of this study, the benefits will be reduced by the introduction underpass for small vehicles were analyzed because heavy vehicles use the intersection above the underpass. However, it was required economic analysis considering both the benefits reduction and the construction costs reduction because it has the effect of reducing the construction cost. Showed that the difference in benefit changes depending on the v/c and heavy vehicles ratio and construction cost was difference by types of underpass. As a result of performing economic analysis with total benefits and construction cost, it was analyzed to be economical in underpass over a certain size. CONCLUSIONS : The result of this study are expected to be able to contribute to reviewing for feasibility due to the small vehicles underpass introduction and economic analysis. The study is case study to the underpass in Daegu. Therefore, the future requires the calculation of benefits reflect a wider range of traffic conditions and the economic analysis to construction cost calculation for various types of grad separation facilities.

• Journal of the Korean Society of Safety
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• v.31 no.3
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• pp.143-155
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• 2016

Recently, a massive loss of life and property is occurring in Korea due to traffic accidents, with the rapid increase in cars. For improvement of traffic safety, the Korea Transportation Safety Authority intensively analyzes accident data in local governments with low traffic safety index, performs a field investigation to extract problems and offers local governments improvements for problems, by conducting the 'Special Survey of Actual Conditions of Traffic Safety' each year, starting 2008. But local governments cannot strongly push forward the improvement projects due to the limited budget and the uncertainty of the improvement plan effects. Therefore, this study suggested a model which applied the Utility concept to the AHP theory, in order to efficiently decide a priority of the improvement plans in accident black spots in consideration of the limited budget of local governments. The number of accidents in each spot for improvement and accident severity, traffic volume, pedestrian volume, the improvement project cost and the accident reduction effect were chosen as evaluation factors for deciding a priority, and data about the improvement plan costs and the accident reduction effects, traffic accidents and traffic volume in the spots to undergo the special research on the real condition of traffic accident in the past were collected from the existing studies. Then, regression analysis was carried out and the Utility Curve of each evaluation factor was computed. Based on the AHP analysis findings, this study devised a priority decision method which calculated the weight and the utility function of each evaluation factor and compared the total utility values. The AHP analysis findings showed that among the evaluation factors, accident severity had the biggest importance and it was followed by the improvement plan cost, the number of accidents, the improvement effect, traffic volume and pedestrian volume. The calculated utility function shows a rise in utility, as the variables of the 5 evaluation factors; the number of accidents, accident severity, the improvement plan effect, traffic volume and pedestrian volume increase and a fall in utility, as the variables of the improvement plan cost increase, since the improvement plan cost is included in the budget spent by a local government.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.6
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• pp.127-132
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• 2008

Traffic intersection control is implemented by the data which is acquired to vechile loop detector. Traffic intersection control equation is Webster equation. which use passig and delayed vechile number. But webster equation is applied to the spot traffic intersection, it is not used to related traffic intersection network system. There is not the approprate remote traffic intersection control, even if there is, it is high cost local network system. Therefore low cost and expert traffic intersection control is realized by internet referencing next and distant intersection traffic information.