• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.4
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• pp.897-905
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• 2015

This research suggested the traffic signal calculation model of active transit signal priority using a shockwave model. Using this signal priority timing optimization model, the shockwave area is computed under the condition of Early Green and Green Extension among active transit signal priority techniques. This study suggested the speed estimation method of backward shockwave using average travel time and intersection passing time. A shockwave area change is calculated according to signal timing change of transit signal priority. Moreover, this signal timing calculation model could determine the optimal signal priority timings to minimize intersection delay of general vehicles. A micro simulation analysis using VISSIM and its user application model ComInterface was applied. This study checked that this model could calculate the signal timings to minimize intersection delay considering saturation condition of traffic flow. In case studies using an isolated intersection, this study checked that this model could improve general vehicle delay of more over ten percentage as compared with equality reduction strategy of non-priority phases. Recently, transit priority facilities are spreading such as tram, BRT and median bus lane in Korea. This research has an important significance in that the proposed priority model is a new methodology that improve operation efficiency of signal intersection.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.10
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• pp.1493-1500
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• 2015

For efficient and economical train operation in low-density railway line, on-board oriented train control system, which reduces expensive wayside equipment, is being developed. In this paper, we discuss a tram signal priority strategy which enables efficient and safe train operation when the developing system is applied to train-tram railway environment. Based on the well-known transit signal priority strategies, we develop a tram signal priority algorithm and conduct simulations by using model-based systems engineering (MBSE) tool. Various considerations such as operation procedure, linkage to existing road traffic system, applicability with respect to crossroad types, and so on, are also dealt with.

• Journal of Korean Society of Transportation
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• v.32 no.4
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• pp.410-420
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• 2014

This research suggests a new tram signal priority model which determines signal timings and tram intersection waiting time using analytical method. This model can calculate the signal timings for Early Green and Green Extension among the active tram signal priority techniques by tram detection time of upstream detector. Moreover, it can determine the tram intersection waiting time that means tram intersection travel time delay from a vantage point of tram travel. Under the active tram signal priority condition, priority phases can bring additional green time from variable green time of non-priority phases. In this study, the signal timing and tram intersection waiting time calculation model was set up using analytical methods. In case studies using an isolated intersection, this study checks tram intersection waiting time ranged 12.7 to 29.4 seconds when variable green times of non-priority phases are 44 to 10 seconds under 120 seconds of cycle length.

• Journal of Korean Society of Transportation
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• v.24 no.7 s.93
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• pp.101-114
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• 2006

Recently due to the increase of cars and city life, the traffic congestion has worsened. It Is particularly worse in the center of the metropolis. Within the general public means, the public transport buses have the advantage of being more cheap, accessible and mobile. But as there is no separate lane for buses, the collision of cars and buses are creating damage to public service. In order to solve this situation, the bus priority signal system has been introduced to reduce the bus travel time and improve its services. The purpose of this study is to establish bus priority signal algorithm which builds bus efficiency under the real-time traffic signal control system and to analyze the effect of it. As the green time was calculated against real time (under the real-time traffic signal control system), compared to existing bus priority signal there was a reduction in cross street loss. The modified cycle was used to maintain signal progression. A case study was carried out using VISSIM simulation model. In result of this study, we found that there was a decrease in bus travel time despite some evidence of car delays and compared to existing bus priority signal the delay of dishonor could be reduced dramatically. The analysed result of person delay using MOE, is that there is evidence that when bus priority signal is in effect, the person delay is reduced.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.3
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• pp.20-33
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• 2021

Modern society is steadily implementing policies to encourage public transportation to cope with the growing traffic demand on limited roads. The expectation is rising for transit signal priority to ensure the speed of buses as the installation of the bus rapid transit(BRT) expands nationwide to secure the competitiveness of buses. On the other hand, the form of BRT stops without considering some aspects of bus operation may increase the number of stops on the bus, thereby reducing the effectiveness of bus signal priority applications. This study suggests the type of bus stop to increase the operation efficiency of buses by analyzing the bus signal priority effect according to the BRT station type using Hannuri-daero, Sejong. The bus signal priority is used to maximize the two-way bandwidth of passenger cars and buses. As a result of the application, the effectiveness of the bus signal priority at the stop causing the double stop of the bus was reduced drastically, and the efficiency of the bus signal priority was increased significantly after improvement. These results are expected to be used as basic data in the form of proper bus stops considering the aspects of traffic operation when designing BRT stops in new towns in the future.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.9
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• pp.1166-1175
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• 2021

We investigate the current situation and development trend of domestic smart city and emergency vehicle priority signal control system analyzing the existing effectiveness of 1) emergency vehicle priority signal control system and 2) control emergency vehicle priority signal, based on domestic and foreign prior research for signal control system security. The effectiveness of time reduction was analyzed through actual application and test operation to emergency vehicles after establishing the system. In addition, for security management and stable service of real-time signal system control we propose improvement for the technical control items of the ISMS-P certification system to secure golden time to protect citizens' precious lives and property in case of emergency by classifying and mapping the existing ISMS-P certification system and the Korea Internet & Security Agency's cyber security guide according to the items of security threats.

• Journal of Korea Multimedia Society
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• v.11 no.8
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• pp.1051-1058
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• 2008

The advancement of technology for image processing and communications makes it possible for current traffic signal controllers and vehicle detection technology to make both emergency vehicle preemption and transit priority strategies as a part of integrated system. Present]y traffic signal control in crosswalk is controlled by fixed signals. The signal control keeps regular signals traffic even with no traffic, when there is traffic, should wait until the signal is given. Waiting time causes the risk of traffic accidents and traffic congestion in accordance with signal violation. To help reduce the risk of accidents and congestion, this paper explains traffic signal control system for the adaptive priority order so that signal may be preferentially given in accordance with the situation of site through the object detect images.

• The Korean Journal of Emergency Medical Services
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• v.26 no.3
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• pp.185-199
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• 2022

Purpose: Prompt arrival of emergency vehicles at the scene is important. Therefore, special cases for emergency vehicles are being applied. However, there remain obstacles that obstruct the prompt arrival during dispatch. Methods: First, a literature review revealed five categories of problems with the emergency vehicle priority signal system. Then, the first Delphi survey was conducted to confirm the validity of the five categories. Further, a second Delphi survey was conducted to identify additional problems, and we used a 5-point Likert scale for a third Delphi survey. Results: A total of 92 items were extracted from preceding studies. The validity of the five categories was confirmed in the first Delphi survey. Then, 123 additional items were derived from the second Delphi survey, and the final 50 items were selected from 93 items obtained from the third Delphi survey. Conclusion: This study revealed problems and improvement measures for improving the operation of the emergency vehicle priority signal system that were not proposed in previous studies.

• 한국ITS학회:학술대회논문집
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• 2010.05a
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• pp.109-113
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• 2010

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.13 no.1
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• pp.15-25
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• 2014

Bus signal priority is a name for various techniques to speed up bus public transport services at intersections with traffic signals. In this study propose methodology to optimize signal times for Early green, Green extension out of the active bus signal priority using deterministic delay model in isolated intersection on median bus lane. Fluctuation is found in the vehicle delay and person delay in the event that using this methodology redistributed to green time and checking slack green time is correct value by sensitivity analysis. As a result of the study, car delay is increased a little and person delay is decreased. As a result of slack green time sensitivity, delay is not much in it if variation of slack green time under 30%. But this methodology effectiveness is under claimed capacity if variation of slack green time over 30%.