• Journal of Korean Society of Transportation
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• v.35 no.1
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• pp.79-89
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• 2017

The purpose of this study is to analyze the current right-turn operation at signalized intersections and suggest appropriate right-turn operation strategy. From field investigation, right-turn signals have not only operated various type and shape, lacking of consistency, but also there was no clear regulations or standards. It could increase drivers' confusion and cause vehicle-to-pedestrian accidents. In order to improve pedestrian safety, there is urgent need to study the regulations and standards regarding to right-turn traffic control. This study suggests appropriate right-turn signal operation strategy. In case of permissive right-turn operation, it should be stated on regulations that red light means right-turn vehicles must stop temporarily at the stop line and then turn right. Necessary conditions for installing right-turn signal for protected operation are that there should have one or more exclusive right-turn lanes and right-turn signal face should contain the lenses with three-color arrow indication. In addition, we assort right-turn operation types as permissive, protected and protected/permissive right-turn and suggest specific signal operation strategy by the types.

• Journal of Korean Society of Transportation
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• v.21 no.2
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• pp.17-31
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• 2003

This study is about throughput analysis of the shared right turn lane at signalized intersection with lane width change. It is expected that the increased width of the right turn shared lane causes to increase the volume of right turn on red(RTOR) In this study, the throughput computation is designed to take into account the lost time which is caused by the blocked right turn due to the stop of through traffic. The saturation flow rate of right turn using the rest of lane after through traffic stops is included as well. Results show that the different RTOR volume levels due to the various shared lane width leads to a difference in throughput. For the shared right turn lanes. throughput capacity for various lane widths is bigger than that of the KHCM as much as from 1.1 to 2.1 times.

• International Journal of Highway Engineering
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• v.12 no.4
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• pp.29-37
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• 2010

This study deals with the Right-Turn Bypass Lane in Roundabout. The purpose of the study is to comparatively analysis the effectiveness questions on the installation of right-turn bypass lane in roundabout. In pursuing the above, this study analyzed after and before of the right turn bypass lane plan by VISSIM software. The right turn bypass lane is formed by control type of yield and control type of joint were compared and analyzed the effects of the operation. The main results analyzed are as follows. First, after Right-Turn Bypass Lane is Installed, the traffic volume rate of the right-turn increasing by average delay time per vehicle is on the gradual decrease, maximum average about 28% with the fact that decreases. Second, control type of yield and control type of joint are both average delay time per vehicle decreasing by the traffic volume rate of the right-turn is on the gradual increase. Control type of joint was analyzed with the fact that has the maximum average about 18% delay decrement efficiency.

• Journal of Korean Society of Transportation
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• v.33 no.5
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• pp.441-448
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• 2015

This study aims to suggest a reasonable signal operation method for right-turn traffic management. It was found that the right-turn vehicle supplementary signal is currently operated without clear regulations or criteria. It was also analyzed that right-turn supplementary signals are used without consistency, there is a risk of traffic accidents due to the discordance between supplementary signals and traffic signals of forward vehicles, there is a lack of basis for prohibition of a right turn when right-turn vehicle's supplementary signal is red and the flashing red signal is used in a different sense from the law. In order to see the effect of the installed right-turn vehicle supplementary signals on traffic signal violation, a field investigation was conducted. As the result, there was a high proportion of signal violation on the approach lane with right-turn supplementary signals and this means that right-turn supplementary signals hardly influenced the reduction in proportion of signal violation during a right turn. Additionally, a survey was carried out to see if there were differences in driver's interpretation of traffic signals depending on the installation of right-turn supplementary signals. As the result of the survey, there were no differences in interpretation of traffic signals depending on the installation of right-turn supplementary signals or the types of right-turn supplementary signals. A right turn when the signal was red did not lead to serious traffic accidents, so it is thought that there should be a careful consideration of a total ban on a right turn when the signal is red, in order to prevent driver's confusion due to the change of the signal system. Unless there is a disturbance to cars and pedestrians after a temporary stop when the signal is red, there is a need to specify that vehicles must stop temporarily in the Road Traffic Act to facilitate a right turn. What this study finally suggested is to use tri-colored arrow signals for right-turn car supplementary signals to convey a signal to a driver clearly.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.1
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• pp.13-21
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• 2015

This study focuses on operational analysis of 2 types of intersection shared lanes. First, the analysis showed that a through & right-turn shared lane is always less used than the adjacent through-only lanes and as a result, operational efficiency deteriorates. To improve the efficiency fine-tuning in signal timing optimization using lane-by-lane traffic volume data is required. Further improvement can be achieved by guiding drivers to equally use the shared lane. For left-turn & U-turn shared lanes, it was found that saturation flow rate is affected by interference between U-turn and conflicting right-turn movements. However, since such interference does not occur in every cycle, a statistical model must be established to develop realistic adjustment factor for saturation flow rate of the shared lane.

• Proceedings of the Safety Management and Science Conference
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• 1999.11a
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• pp.275-290
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• 1999

현재 우리나라의 수많은 관광지에서는 극심한 교통혼잡과 주차난을 겪고 있다. 본 연구는 대포항 교차로와 대포항 주차장의 기하구조 및 이용실태를 조사한 후, 현재 교차로와 주차장 진ㆍ출입로의 기하구조와 주차장 운영현황 및 그 이용실태의 문제점 분석을 목적으로 하고 있다. 이를 위해 본 연구에서는 현장에서 실제 조사한 교차로의 도로조건과 주차장의 진ㆍ출입로는 조사된 그림(1. 대포항 교차로, 2. 대포항 주차장 구획도)으로 분석하고 주차자의 운영현황 및 이용실태는 현장조사를 토대로 누적주차대수, 주차회전율, 차량당 평균주차지속시간, 주변도로 혼잡영향 분석 등의 방법을 통해 얻어진 결과로 분석할 것이다. 분석결과, 주차장 인접 교차로에서는 버스정류장과 우회전 차로의 합류, 우회전 차로와 주차장 진ㆍ출입로의 합류 등의 기하구조상의 문제로 직진ㆍ우회전 차량, 주차장 진ㆍ출입 차량의 혼잡을 예상할 수 있었고, 주중에는 13시 51분에, 주말에는 10시55분에 이미 주차장은 포화상태를 보여 최초 대기차량이 발생하였으므로 주차공급이 부족함을 알 수 있었다. 그러나, 관광지라는 특성상 기후나 시기적 영향을 많이 받는다는 점을 감안해야할 것이다. 따라서, 관광지 주차장의 조사는 여러 가지 측면에 더 연구되어질 필요가 있다.

• Journal of Korean Society of Transportation
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• v.22 no.4 s.75
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• pp.43-56
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• 2004

The KHCM procedure is a micro level analysis at signalized intersections requiring a lot of input variables and complex computations. The research was to investigate the possibility of simplifying the analysis procedures by using the generalized or the combined variables that less influence on the adjusted traffic volume and through-car equivalents of left or right turns. It was also tried to make lane grouping into directional flow ratio(v/s) based on a field surveys. The maximum and minimum values of each variables were compared with each other through the KHCM analysis procedures in terms of control delay. The lane grouping and the synthetical influence of a simplified method was evaluated with the scenario built in prevailing maximum and minimum conditions. The study showed that the control delay was not significantly sensitive to the selected variables and the lane grouping and their synthetical influence as well.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.3
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• pp.1-13
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• 2020

When pedestrians cross a pedestrian crossing during a pedestrian signal, there is a problem that pedestrians are exposed to the danger of traffic accidents due to permissive-left turning and right-turning vehicles. In order to solve this problem, there is an increasing demand to improve the traffic signal system to increase pedestrian safety at the signal crossing. This study aims to examine the feasibility of introducing a leading pedestrian interval(LPI) to prevent conflict between unprotected left and right turn vehicles and pedestrians. In this study, the need for LPI was surveyed by experts and the general public. As a result of the survey, many opinions indicated that the introduction of LPI was necessary. In addition, after selecting the non-protected left and right turn pilot operation targets, LPI was installed on two signal intersections. After installation, the speed analysis of the arrival vehicle in the pedestrian crossing and the violation rate of the pedestrian signal were analyzed. As a result of analysis, when the walking signal was equalized, the speed of the arriving vehicle in the pedestrian crossing was reduced, and the violation rate of the walking signal was improved.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.2 no.1 s.2
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• pp.41-52
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• 2003

The purpose of this study was to test the effects of the pedestrian green signal adjustment on clearance of the turning vehicles impeding the through traffic flow at the signalized intersections, and thereby, suggest some operational criteria for adjustment of the pedestrian green signal. In order to test such effects, the pedestrian green time was adjusted so that it could started a few seconds later than the vehicle green time during peak hours, and thereby, the turning vehicle volume not cleared at the intersection was measured by extending the time gap by 2 seconds. (In general, the pedestrian green signal turns on at the same time as the vehicle green signal.) The results of this test can be summed up as follows; first, the longer the time gap was, the turning vehicle volume not cleared from the intersection decreased more. Second, in case there existed a storage space between intersection and crosswalk the effect of the turning vehicles on the through traffic flows was minimal. Third, at the pelican, the effect of the turning vehicles on the through traffic flow was minimal due to the structure of the intersection and the phase sequence. In conclusion, it was found that the adjustment of pedestrian green signal had the effect of enhancing the intersection operation. When adjusting the pedestrian green signal, it was deemed necessary to thoroughly survey the geometric structure of the intersection and collect the data on the turning traffic volume and thereby, apply the results of analysis flexibly to each intersection.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.5
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• pp.57-70
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• 2009

According to the change of the traffic conditions, the requirement of controlling the separated left(or right) turn, the median bus lane and bicycle signal is increasing. However, the traffic signal controller standard based on the four-set lights restricts to control the three-set lights which control the separated direction and kind of traffics. This study suggests the method to control the three-set lights signal by improving the hardware and software for the traffic signal controller which is operated currently in the traffic scene. The 6 output ports of Load Signal Unit(LSU) which is consisted of Pedestrian Red, Pedestrian Green, Red, Yellow, Arrow and Green signal reconstitute 2 rows of the Red, Yellow, Green for three-set lights while the Signal Map data's code values which control the signal step of an individual Ring and LSU are established to adjust the LSU's output ports(R1 Y1 G1 R2 Y2 G2) of the three-set lights. The effect of using the separated through/left turn and the median lane bus signal of three-set lights is analyzed from a Mangwoo intersection in Seoul. The results of analysis show that the delay time of the east-west direction where the median bus lane is operated is especially improved with over 70 sec/veh.