• 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.

• 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.

• Journal of the Ergonomics Society of Korea
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• v.28 no.3
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• pp.63-71
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• 2009

A car navigation system as an in-vehicle route guidance information (RGI) offers a state-of-the-art technological solution to driver navigation in an unfamiliar area. However, the RGI is provided by some pre-determined options in terms of the interface between a driver and a car navigation system. Drivers occasionally pass the target intersection owing to non- or late- recognizing it. This paper is examined the position of driver's turn signal operation and intersection recognition approaching at the target intersection which is difficult to identify, as a fundamental research on developing the additional RGI connecting with the turn signal control. The field experiment was conducted to measure distances of the turn signal operation and the intersection recognition from the target intersection according to left turns, right turns, and landmarks at adjacent intersection. And glance behavior to the car navigation display was evaluated by using an eye camera. The results of the field study indicate that, most case of driving, drivers operate the turn signal until 40m to 50m before coming to the target intersection. The driving simulator experiment was performed to examine the effectiveness of providing the additional RGI when drivers did not operate the turn signal approaching at the target intersection based on the results of the field study. To provide the additional RGI is effective for the intersection identification and recognition, and expected to improve the traffic safety and the comfort for drivers.

• International Journal of Highway Engineering
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• v.15 no.4
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• pp.135-146
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• 2013

PURPOSES : This study aimed to analyze the impact the operation of pre-signals at 4-leg signalized intersections and present primary environmental factors of roads that need to be considered in the installation of pre-signals. METHODS : Shift of proportions safety effectiveness evaluation method which assesses shifts in proportions of target collision types to determine safety effectiveness was applied to analyze traffic crash by types. Also, Empirical Bayes before/after safety effectiveness evaluation method was adapted to analyze the impact pre-signal installation. Negative binomial regression was conducted to determine SPF(safety performance function). RESULTS : Pre-signals are effective in reducing the number of head on, right angle and sideswipe collisions and both the total number of personal injury crashes and severe crashes. Also, it is deemed that each factor used as an independent variable for the SPF model has strong correlation with the total number of personal injury crashes and severe crashes, and impacts general traffic crashes as a whole. CONCLUSIONS: This study suggests the following should be considered in pre-signal installation on intersections. 1) U-turns allowed in the front and rear 2) A high number of roads that connect to the intersection 3) Many right-turn traffic flows 4) Crosswalks installed in the front and rear 5) Insufficient left-turn lanes compared to left-turn traffic flows or no left-turn-only lane.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.2142-2143
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• 2011

Amphibious possible, and good fuel economy, so as leisure and transport has increased the use of hovercraft. Fire started in Korea, the prevalence is increasing in demand as the trend has been increasing steadily. In this paper, the hovercraft's forward and backward direction can be controlled in order to free the reverse bucket control system was developed. Control due to development by promoting the flow of air and turn right, turn left and easy to reverse the life-saving and stable at high speed, etc. has made possible the operation of hovercraft. To prove the validity of the proposed controller in Matlab simulation and the actual delivery at the firehouse, built into a model for the demonstration test was performed.

• 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.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.3180-3186
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• 2011

A segmented scissors type switch has been developed for the urban transit maglev demonstration line to be commercialized near Incheon International Airport in 2013. Based on the design of the previous segmented 3-way switch, the scissors switch is composed of four segmented 2-way switches up/down and left/right and a turn table in the mid point. The main function of the scissors switch is to change the running direction of the train at end terminals. The developed scissors switch is planned to be installed in front of the 102 station, which has a side platform, of the demonstration line. The total length of the switch is 65m and the distance between the up and down track centerlines is 6m. The 2-way switches and turn table are made of steel box type beams, and have their own driving unit, locking unit, control unit, levitation and propulsion rails, and so on. Installed in the factory, a 100,000-cycle continuous operation test was carried out after manual and automatic test operations. The applicapability of the developed switch was verified through the measurements of the linearity of the track after repetitive operations, the mechanical operation noise, the load of the main driving motor, the safety of the control panel, the natural frequency of the girder, the deformation of the girder, and so on.

• Journal of the Ergonomics Society of Korea
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• v.34 no.2
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• pp.85-101
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• 2015

Objective: The purpose of this study was to develop and evaluate smart secondary controls using iPad for the drivers with physical disabilities in the driving simulator. Background: The physically disabled drivers face problems in the operation of secondary control devices that accept a control input from a driver for the purpose of operating the subsystems of a motor vehicle. Many of conventional secondary controls consist of small knobs or switches that physically disabled drivers have difficulties in grasping, pulling or twisting. Therefore, their use while driving might increase distraction and workload because of longer operation time. Method: We examined the operation time of conventional and smart secondary controls, such as hazard warning, turn signal, window, windshield wiper, headlights, automatic transmission and horn. The hardware of smart secondary control system was composed of iPad, wireless router, digital input/output module and relay switch. We used the STISim Drive3 software for driving test, customized Labview and Xcode programs for interface control of smart secondary system. Nine subjects were involved in the study for measuring operation time of secondary controls. Results: When the driver was in the stationary condition, the average operation time of smart secondary devices decreased 32.5% in the normal subjects (p <0.01), 47.4% in the subjects with left hemiplegic disabilities (p <0.01) and 38.8% in the subjects with right hemiplegic disabilities (p <0.01) compared with conventional secondary devices. When the driver was driving for the test in the simulator, the average operation time of smart secondary devices decreased 36.1% in the normal subjects (p <0.01), 41.7% in the subjects with left hemiplegic disabilities (p <0.01) and 34.1% in the subjects with right hemiplegic disabilities (p <0.01) compared with conventional secondary devices. Conclusion: The smart secondary devices using iPad for people with hemiplegic disabilities showed significant reduction of operation time compared with conventional secondary controls. Application: This study can be used to design secondary controls for adaptive vehicles and to improve the quality of life of the people with disabilities.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.5 no.1 s.9
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• pp.21-30
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• 2006

For urban highway network, traffic control strategy paradigm has been shifted from the private auto-oriented to the public transit-oriented. Introduction of exclusive median bus lanes (EMBL) in Seoul, Korea, has especially accelerated such changes in transportation policy and thus highway environment. Left-turning movement treatment at signalized intersections where EMBL pass through has been emerged as one of the rising problems associated with a current signal head with 4-signal lens, the Korea standard. This study proposes a new signal phase operation scheme for signal operation at an isolated intersection where EMBL pass through. The authors propose to use of an exclusive bus signal head indicating right-of-way of transits on EMBL only. Based on it, three different phase operation scheme were developed for left-turn treatments for traffic control with (1) traffic responsive control mode and (2) time-of-day traffic control mode. In addition, methodologies to design and develop signal maps for the proposed signal phase schemes are also developed. The proposed operation can only be possible when additional uses of signal state relay boards are allowed.