• Journal of Korean Society of Transportation
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• v.17 no.1
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• pp.19-28
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• 1999

This study deals with developing Critical GaP Model and Merge Probability Model which describe traffic patterns in the microscopic view, for the Purpose of suggesting a proper design criteria within the climbing lane section. Minimum tolerance speeds at the end of the climbing lane are calculated 60km/hr for 2-lane freeway, and 75km/hr for 4-lane freeway. In case of 2-lane freeway, the result is same as existing design criteria. and a new value is 15km/hr higher than existing design criteria for 4-lane freeway. In addition, auxiliary length at the end of the climbing lane is needed about 200m for 4-lane freeway to adjust high minimum tolerance speed. Therefore we propose to increase minimum tolerance speed for 4-lane freeway.

• Journal of Korean Society of Transportation
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• v.10 no.1
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• pp.21-40
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• 1992

We examine primarily the existing study procedures for freeway weaving section by comparing speed estimates. Most methods have poor predictions because of neglecting the weaving vehicle influ-ence. In this study we develop the speed prediction equation considering the weaving influence area i.e, weaving box. Assuming that speeds outside weaving box are similar to speeds in freeway basic sec-tions we develop speed equation in box based on the field data. Moreover level of service criteria and weaving analysis precedure are proposed under the new speed prediction equation.

• Journal of Korean Society of Transportation
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• v.10 no.1
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• pp.5-20
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• 1992

Even though the types of ramp facilities in Korea are not various like other countries operations in these sections are very important because ramp merging and /or diverging flow affects freeway overall sections. In this study existing methodologies especially the gap acceptance model and the regression model in USHCM are evaluated with our field data. By gap acceptance model the merging capacity is founded 2.360 pcph which is increased by 7% than the capacity of freeway basic section. And in comparison of actual lane 1 volume to the estimation volume by HCM model the model slightly overestimates the actual volue.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.4
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• pp.61-66
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• 2013

The central core of the Traffic Management System is an Incident Management System. Whole approach has been component-orientated, with a secondary emphasis being placed on the traffic characteristics at the sites. The first action taken during the development process was the selection of the required data for each components within the existing infrastructure of Algeria freeway system. After review and analysis of existing incident detection methodologies, Paramics was utilized to test the performance of APID, DELOS algorithms. The existing system of Algeria freeway was tested in a different configuration at different sections of freeway, thereby increasing the validity and scope of the overall findings. The incident detection module has been performed according to predefined system validation specifications. The Paramics simulation was done with the use of synchronous analysis, thereby providing a means for testing the incident detection module.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.5
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• pp.84-92
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• 2006

Freeway Corridors consist of urban freeways and parallel arterials that drivers can use alternatively. Ramp metering in freeways and signal control in arterials are contemporary traffic control methods that have been developed and applied in order to improve traffic conditions of freeway corridors. However, most of the existing studies have focused on either optimal ramp metering in freeways, or progression signal strategies between arterial intersections. There have been no traffic control systems in Korea that integrates the freeway ramp metering and arterial signal control. The effective control strategies for freeway operations may cause negative effects on arterial traffic. On the other hand, traffic congestion and bottleneck phenomenon of arterials due to the increasing peak-hour travel demand and ineffective signal operation may generate an accessibility problem to freeway ramps. Thus, the main function of the freeway which is the through-traffic process has not been successful. The purpose of this study is to develop an integrated control model that connects freeway ramp metering systems and signal control systems in arterial intersections. And Optimization of integrated control model which consists of ramp metering and signal control is another purpose. Optimization results are verified by comparison with the results from MATDYMO.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.1
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• pp.8-15
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• 2007

Freeway corridors consist of urban freeways and parallel arterials that drivers can use alternatively. Ramp metering in freeways and signal control in arterials are contemporary traffic control methods that have been developed and applied in order to improve traffic conditions of freeway corridors. However, most of the existing studies have focused on either optimal ramp metering in freeways, or progression signal strategies between arterial intersections. There have been no traffic control systems in Korea that integrates the freeway ramp metering and arterial signal control. The effective control strategies for freeway operations may cause negative effects on arterial traffic. On the other hand, traffic congestion and bottleneck phenomenon of arterials due to the increasing peak-hour travel demand and ineffective signal operation may generate an accessibility problem to freeway ramps. Thus, the main function of the freeway which is the through-traffic process has not been successful. The purpose of this study is to develop an integrated control model that connects freeway ramp metering systems and signal control systems in arterial intersections. And Optimization of integrated control model which consists of ramp metering and signal control is another purpose. The design of experiment, neural network, and simulated annealing are used for optimization.

• Journal of Korean Society of Transportation
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• v.13 no.4
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• pp.117-132
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• 1995

Peak-period congestion is a frequent occurrence on many freeways. Entrance-metering is an effective strategey in improving urban freeway traffic condition. This paper describes the prodecure to develop a computer program for proparing optimum ramp-metering stategies. Four existing ramp-metering optimaization models wer reviewed and evaluated in regared to their theories and actural performances. A optimization model was proposed in this paper. Final model takes aform of quadratic programming. The performance of the propeosed model wastest using FREFLO.

• Journal of Korean Society of Transportation
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• v.23 no.4 s.82
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• pp.57-69
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• 2005

The goal of this paper is to develop freeway Origin-Destination (OD) demand estimation model using real-time traffic data collected from Freeway Traffic Management System (FTMS). In existing research, the micro-simulation models had been used to get a link distribution proportion by time process. Because of hi-level problem between the traffic flow model and the optimal OD solution algorithm, it is difficult for the existing models to be loaded at FTMS. The formulation of methodology proposed in this paper includes traffic flow technique to be able to remove the bi-level problem and optimal solution algorithm using a genetic algorithm. The proposed methodology is evaluated by using the real-time data of SOHAEAN freeway, South Korea.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.3D
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• pp.329-334
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• 2009

The various behaviors of vehicular traffic flow are generated through both car-following and lane-changing behaviors of vehicles. Especially lane-usage varies by lane-changing behaviors. In the area of microscopic vehicle simulation, a lane-changing model connected to a car-following model parallel is essential to generate both various traffic flows relationships and laneusages. In Korea, some studies on car-following models have been reported, but few studies for lane-changing models stay in the beginning stage. In this paper, a two-lane changing model for the simulation modeling of large freeway network is introduced. The lane-changing model is developed based on CA (Cellular Automata) model. The developed model is parallel combined with an existing CA car-following model and tested on a closed link system. The results of simulation show that the developed model generates the various behaviors of lane usage, which existing CA lane-changing models could not generate. The presented model is expected to be used for the simulation of more various freeway traffic flows.

• KIISE Transactions on Computing Practices
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• v.21 no.3
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• pp.223-238
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• 2015

Ramp metering is the most effective and direct method to control a vehicle entering the freeway. This paper proposed the new density-based ramp metering method. Existing methods that use the flow data had low reliability data and can have various problems. Also, when the ramp metering was operated by freeway congestion, the additional congestion and over-capacity can occur in the ramp. To solve this problem with the existing method, the proposed method used the density and acceleration data of the freeway and considered the ramp status. The developed strategy was tested on Trunk Highway 62 west bound (TH-62 WB) in Minnesota Twin-City and compared with Stratified Zone Metering(SZM), which had been operating in the Twin-City freeway. To constitute the experiment environment, the VISSIM simulator was used. The Traffic Information and Condition Analysis System (TICAS) was developed to control the PTV VISSIM simulator. The experiment condition was set between 2:00 PM and 7:00 PM, Oct 5th, 2014 during severe traffic congestion. The simulation results showed that total travel time was reduced by 20% for SZM. Thus, we solved the problem of ramp congestion and over-capacity.