• Journal of Korean Society of Transportation
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• v.17 no.3
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• pp.87-96
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• 1999

It is very important to analyze the capacity of basic freeway section in terms of planning, design, and operation of roads. Capacity, in Korean Highway Capacity Manual was Published in 1992, had been determined by data collected in only 4-lane freeway. But, Korea is continuously planning and constructing multi-lane roads for increasing traffic demand. For this reason, it is necessary to determine the capacity for multi-lane freeways. This study goals are two-fold the determination of lane capacity for 8-lane freeway; and the development of methodology determining total capacity using lane friction factor This study utilized the data collected by loop detectors at a station of FTMS in Kyungbu expressway. For determining capacities, this study analyzed maximum flow rate in various aspects such as collecting period, each lane, and total lane in one-way. In addition, this study evaluated the breakdown in traffic flow relations in order to find out interrelation of breakdown among lanes. Through this analysis, this study determined lane friction factors, critical speed, and critical density. Finally, this study expressed a new methodology of capacity analysis for multi-lane freeways using some findings from this analysis.

• Journal of Auto-vehicle Safety Association
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• v.8 no.1
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• pp.13-18
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• 2016

More than 80 percent of traffic accidents related with lane departure believed to be the result of crossing the lane due to either negligence or drowsiness of the driver. Lane-departure related accident in the highway usually involve high fatality. Even though LDWS is believed to prevent accident 25% and reduce fatalities by 15% respectively, its effectiveness in performance is yet to be confirmed in many aspects. In this study, the vehicle lateral locations relative to warning zone envelop (earliest and latest warning zone) defined in ISO standard, ECE and NHTSA regulations are compared with respect to various factors including delays, vehicle speed and vehicle heading angle with respect to the lane. Since LDWS is designed to be activated at the speed over 60 km/h, vehicle speed range for the study is set to be from 60 to 100 km/h. The vehicle heading angle (yaw angle) is set to be up to 5 degree away from the lane (abrupt lane change) considering standard for lane change test using double lane-change test specification. The TLC is calculated using factors like vehicle speed, yaw angle and reaction time. In addition, the effect of vehicle type and reaction time have been considered to assess LDWS safety.

• International Journal of Highway Engineering
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• v.17 no.1
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• pp.99-104
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• 2015

PURPOSES : It is well known that experts determined the current standard dimensions of freeway lane markings. However, rigorous engineering rationale could be insufficient regarding whether or not the standard dimensions account for how visible the markings are to the driver. In this study, we seek to optimize the dimensions of freeway lane markings to improve their visibility to drivers. METHODS : The study was conducted as follows. First, alternative lane marking dimensions were selected which could be installed in a test construction site. Second, a video recording was made while driving on the test construction site. Third, subjects were shown the recorded video and then instructed to indicate their preference from among the various lane markings. Lastly, t-tests were applied to assess the statistical significance of differences in the preferences expressed. RESULTS : According to the t-test results, there was no significant difference in the preferences expressed regarding the lane marking widths. However, with regard to the dimensions of freeway lane marking, which represents line marking lengths, gap lengths, and widths of marking, the subjects expressed a preference for specific dimensions such as 6 m:12 m,13 cm, 8 m:12 m,10 cm and 6 m:12 m,10 cm. CONCLUSIONS : In considering the dimensions of freeway lane markings and their relation to visibility by the driver, it was found that dimensions such as 6 m:12 m,13 cm, 8 m:12 m,10 cm and 6 m:12 m,10 cm.

• International Journal of Highway Engineering
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• v.15 no.6
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• pp.135-141
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• 2013

PURPOSES : The lack of details of design guideline for zig-zag shaped section approaching central bus stop leads an traffic accident proneness. So, this study analysed the geometric elements of central bus stop area in terms of vehicle dynamics and suggested design alternatives. METHODS : The study analysed a dynamic behaviour of bus moving in and out of zig-zag shaped section using Auto-Turn under scenarios. Based upon dynamic analysis, the study found out the width of overtaking lane is the most influential factor for a safe moving at zig-zag alignment. RESULTS : The width of overtaking lane at design speed of 40, 50, and 60 km/h respectively was suggested given taper ratio of 1 to 10 required for Bus Rapid Transit (BRT), and the lane width is not wider than 4.0m which possibly makes two vehicles using the same lane. Also, the width of overtaking lane which mitigates the taper ratio was suggested with the same restriction about the maximum lane width. CONCLUSIONS : The results of the study can be used to prepare a design guideline on zig-zag shaped alignment of central bus exclusive lanes. The more stable moving is expected by applying the design alternatives suggested, therefore the lower rate of traffic crashes at the vicinity of central bus stops.

• Journal of Mechanical Science and Technology
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• v.17 no.11
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• pp.1693-1703
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• 2003

This paper presents a new local obstacle avoidance method for indoor mobile robots. The method uses a new directional approach called the Lane Method. The Lane Method is combined with a velocity space method i.e., the Curvature-Velocity Method to form the Lane-Curvature Method (LCM). The Lane Method divides the work area into lanes, and then chooses the best lane to follow to optimize travel along a desired goal heading. A local heading is then calculated for entering and following the best lane, and CVM uses this local heading to determine the optimal translational and rotational velocities, considering some physical limitations and environmental constraint. By combining both the directional and velocity space methods, LCM yields safe collision-free motion as well as smooth motion taking the physical limitations of the robot motion into account.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.1
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• pp.51-60
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• 2013

In this paper, to control the existing headlamp control system using steering wheel angle more efficiently and more actively, image processing algorithm which improved the detection rate of lane at night based on camera was suggested. And to recognize road lane more clearly in the conditions of low illumination, new algorithms were developed in the aspects of improving brightness, extracting clear lane edge and using the characteristics of lane. Through this research, it turned out that lane detection ability by using the normalized stretching, angular mask and expected-area scan have good performance in the night compare to existing algorithms.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.815-818
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• 2016

Forward collision warning systems(FCWS) and lane departure warning systems(LDWS) need regions of interest for detecting lanes and objects as road regions. In general, the lane departure warning system using a vehicle front camera is tracking a lane curve using RANSAC or the like in the form of a straight line obtained image are compared with the center of the vehicle. This algorithm has weaknesses that requires a wide range of the lane being vulnerable to the curve. This paper presents an algorithm that checks whether the current lane departure by car from the Top-view space. The algorithm also can check whether the vehicle in the lane departure of the narrow range, and shows the result that is almost not affected by noise.

• Computers and Concrete
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• v.19 no.6
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• pp.725-736
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• 2017

This paper presents the two-, three-, and four-lane transverse reduction factor based on FEA method, probability theory, and the recently actual traffic flow data. A total of 72 composite girder bridges with various spans, number of lanes, loading mode, and bridge type are analyzed with time-varying static load FEA method by ANSYS, and the probability models of vehicle load effects at arbitrary-time point are developed. Based on these probability models, in accordance to the principle of the same exceeding probability, the multi-lane transverse reduction factor of these composite girder bridges and the relationship between the multi-lane transverse reduction factor and the span of bridge are determined. Finally, the multi-lane transverse reduction factor obtained is compared with those from AASHTO LRFD, BS5400, JTG D60 or Eurocode. The results show that the vehicle load effect at arbitrary-time point follows lognormal distribution. The two-, three-, and four-lane transverse reduction factors calculated by using FEA method and probability respectively range between 0.781 and 1.027, 0.616 and 0.795, 0.468 and 0.645. Furthermore, a correlation between the FEA and AASHTO LRFD, BS5400, JTG D60 or Eurocode transverse reduction factors is made for composite girder bridges. For the two-, three-, and four-lane bridge cases, the Eurocode code underestimated the FEA transverse reduction factors by 27%, 25% and 13%, respectively. This underestimation is more pronounced in short-span bridges. The AASHTO LRFD, BS5400 and JTG D60 codes overestimated the FEA transverse reduction factors. The FEA results highlight the importance of considering span length in determining the multi-lane transverse reduction factors when designing two-lane or more composite girder bridges. This paper will assist bridge engineers in quantifying the adjustment factors used in analyzing and designing multi-lane composite girder bridges.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.3
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• pp.434-442
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• 2018

In this paper, we propose a road lane color recognition method from the image obtained from a driving vehicle. In autonomous vehicle techniques, lane information becomes more important as the level of autonomous driving such as lane departure warning and dynamic lane keeping assistance is increased. In particular the lane color recognition, especially the white and the yellow lanes, is necessary technique because it is directly related to traffic accidents. In this paper, color information of lane and road area is mapped to a 2-dimensional S-color space based on lane detection. And the center of the feature distribution is obtained by using an improved mean-shift algorithm in the S-color space. The lane color is determined by using the distance between the center coordinates of the color features of the left and right lanes and the road area. In various illumination conditions, about 97% color recognition rate is achieved.

• Journal of Korean Society of Transportation
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• v.26 no.4
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• pp.41-49
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• 2008

Signalized intersection analysis using lane groups often generalizes distinct characteristics of individual lanes. An individual lane level analysis procedure is proposed. The method can assess individual lane LOS without additional data collection efforts. Analysis results of the proposed method were compared with the current HCM analysis results and outputs of aaSIDRA, which can calculate intersection performance lane-by-lane. The results showed individual lane analysis mostly produces similar results with HCM and aaSIDRA. However, lane analysis results for permitted left lanes showed some differences with aaSIRDRA due to the different method of assessing saturation flow rate of the permitted left turn movement. It is expected that the proposed method could complement the weaknesses of current HCM signalized intersection analysis.