• Journal of Korean Society of Transportation
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• v.30 no.1
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• pp.59-72
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• 2012

In aspects of traffic operation, a climbing lane may cause traffic congestion if the volume of traffic (v/c) grows and the ratio of heavy vehicle increases. Conversely, it would be effective, if the climbing lane is dynamically operated according to changes in traffic flow. However, there are no guideline to effectively control this climbing lane in aspects of traffic operation. In this study, we examine the necessity of flexible traffic operation criteria and its process for dynamic traffic management and also establish and analyze the effect of flexible traffic operation criteria in accordance with traffic properties using an example of climbing lane. We selected the operation criteria (critical travel speed), which decides whether to operate or close the climbing lane when the average travel speed of climbing lane is 50km/h based on VISSM (microscopic traffic simulation) analysis of Nakdong junction towards Masan with the volume of traffic (v/c), ratio of heavy vehicle as the traffic operation parameters. Based on the simulation result in accordance with the volume of traffic by the operation mode of climbing lane, the analysis on the effect of dynamic traffic management of climbing lane showed that the dynamic traffic management provides more convenience compare to the operation and close of climbing lane. Thereby, we proved that the dynamic traffic management of climbing lane is more effective.

• International Journal of Highway Engineering
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• v.15 no.6
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• pp.125-133
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• 2013

PURPOSES : The purpose of this study is to propose delay-minimizing operation methodology of a signalized intersection based upon optimization of lane-uses on approaching lanes for an intersection. METHODS : For the optimization model of lane-uses, a set of constraints are set up to ensure feasibility and safety of the lane-uses, traffic flow, and signal settings. Minimization of demand to saturation flow ratio of a dual-ring signal control system is introduced to the objective function for delay minimization and effective signal operation. Using the optimized lane-uses, signal timings are optimized by delay-based model of TRANSYT-7F. RESULTS : It was found that the proposed objective function is great relation with delay time for an intersection. From the experimental results, the method was approved to be effective in reducing delay time. Especially, cases for two left-turn lanes reduced greater delays than those for a left turn lane. It is noticed that the cases for different traffic volume by approach reduced greater delays than those for the same traffic volume by approach. CONCLUSIONS : It was concluded that the objective function is proper for lane-uses optimizing model and the operation method is effective in reducing delay time for signalized intersections.

• International Journal of Highway Engineering
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• v.15 no.3
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• pp.85-92
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• 2013

PURPOSES: The purpose of this paper is to estimate expected effects on traffic operational and economic aspects of 2+1 roads application in Korea. METHODS : Micro simulation study using VISSIM 5.0 was used to analyze the operation efficiency of 2+1 roads compared to two-lane highways and four-lane highways. Some scenarios for various traffic volumes were set up in order to analyze the effect of 2+1 roads under various traffic situations. Also imaginary road networks were set up for each type of roads. The MOEs to measure the operation efficiency were selected with average travel speed and delay. For analyzing economic effect of 2+1 roads, construction cost of a specific imaginary 2+1 road was compared to construction cost of a four-lane highway with same conditions. RESULTS: The results of study show that a 2+1 road is more effective with 19 percents higher average travel speed and 39 percents lower average delay than a two-lane highway. In the economic analysis, construction costs to construct a 2+1 road are saved as approximately 26.4~40.7 percents when compared to construction of four-lane highway. CONCLUSIONS: It can be concluded that 2+1 roads can improve the traffic operational level of service for two-lane highways and 2+1 roads can be applied as an effective design alternative for higher-volume two-lane highways in Korea.

• Journal of the Korean Society of Safety
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• v.27 no.3
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• pp.153-160
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• 2012

Various social problems such as traffic congestion, car accidents and environmental problems(air pollution, noises etc.) have been happening in the Seoul metropolitan area that has the car oriented traffic system providing cars continuously. Along with this, the financial burden caused by current oil price anxiety made paradigm shift from caroriented to public transportation-oriented. Its typical example is an arterial branch bus system changing(bus lane through the center of main road) started in Seoul in July, 2004. But study on safety analysis of bus lane and characteristic of accidents are not sufficient enough to now. The bus lanes are expanded to provide roads for better traffic operation and accidents between buses and pedestrians or ordinary vehicles are considered main problems. This study divided each bus route of median bus lane(bus-only lane through the center of main roads) and bus lane at roadside by intersection and collected and analysed data about influence variables of bus accidents chosen in each section. We constructed a logistic model using collected data. As a result, bus lane at roadside are used by both buses and other kinds of vehicles differently from median bus lane and showed such characteristic in accident influence. Therefore access management to factors causing conflict and improvement of operation management are required. In case of median bus lane, the more buses moving general vehicle lane and traffic volume of section were, the more accidents happened. In case that stop line of center lane is not backward, view blocking of vehicles turning left caused accidents.

• IEMEK Journal of Embedded Systems and Applications
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• v.18 no.5
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• pp.225-231
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• 2023

With the recent surge in the autonomous driving market, the significance of lane detection technology has escalated. Lane detection plays a pivotal role in autonomous driving systems by identifying lanes to ensure safe vehicle operation. Traditional lane detection models rely on engineers manually extracting lane features from predefined environments. However, real-world road conditions present diverse challenges, hampering the engineers' ability to extract adaptable lane features, resulting in limited performance. Consequently, recent research has focused on developing deep learning based lane detection models to extract lane features directly from data. In this paper, we classify lane detection models into four categories: cluster-based, curve-based, information propagation-based, and anchor-based methods. We conduct an extensive analysis of the strengths and weaknesses of each approach, evaluate the model's performance on an embedded board, and assess their practicality and effectiveness. Based on our findings, we propose future research directions and potential enhancements.

• 한국ITS학회:학술대회논문집
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• 2008.11a
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• pp.309-310
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• 2008

• 한국도로학회:학술대회논문집
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• 2009.11a
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• pp.697-701
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• 2009

• Journal of Korean Society of Transportation
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• v.12 no.1
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• pp.151-172
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• 1994

The objective of study is to evaluate design standards related to the allowable truck speeds, taper length and sign requirements together with the operating practices and economic justification for climbing lanes. Field surveys were carried out on seven climbing lanes, three on two-lane and four on four-lane freeways. Data collected are traffic volume, speed, usage rate and delay. It is found that current design criteria for determining the length of climbing lane, taper lengths, and traffic sign requirements must be upgraded. It is also recommended that regulations on the use of climbing lane be established to make it more effective. Further, economic analysis revealed that the climbing lane is economically justified for two-lane and four-lane freeway if the AADT is over 4,577 and 5,116 vehicles respectively.

• Journal of the Korea Society of Computer and Information
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• v.24 no.11
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• pp.29-39
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• 2019

As mobile robot applications increase in real life, the need of low cost autonomous driving are gradually increasing. We propose a novel vision-based real-time lane detection and tracking system that supports autonomous driving of mobile robots in constrained tracks which are designed considering indoor driving conditions of mobile robots. Considering the processing of lanes with various shapes and the pre-adjustment of operation parameters, the system structure with multi-operation modes are designed. In parameter tuning mode, thresholds of the color filter is dynamically adjusted based on the geometric property of the lane thickness. And in the unstable input mode of curved tracks and the stable input mode of straight tracks, lane feature pixels are adaptively extracted based on the geometric and temporal characteristics of the lanes and the lane model is fitted using the least-squared method. The track centerline is calculated using lane models and the motion model is simplified and tracked by a linear Kalman filter. In the driving experiments, it was confirmed that even in low-performance robot configurations, real-time processing produces the accurate autonomous driving in the constrained track.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.7
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• pp.107-116
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• 2014

This paper presents camera-based road surface marking detection methods suited to sensor fusion-based positioning system that consists of low-cost GPS (Global Positioning System), INS (Inertial Navigation System), EDM (Extended Digital Map), and vision system. The proposed vision system consists of two parts: lane marking detection and RSM (Road Surface Marking) detection. The lane marking detection provides ROIs (Region of Interest) that are highly likely to contain RSM. The RSM detection generates candidates in the regions and classifies their types. The proposed system focuses on detecting RSM without false detections and performing real time operation. In order to ensure real time operation, the gating varies for lane marking detection and changes detection methods according to the FSM (Finite State Machine) about the driving situation. Also, a single template matching is used to extract features for both lane marking detection and RSM detection, and it is efficiently implemented by horizontal integral image. Further, multiple step verification is performed to minimize false detections.