• The Transactions of the Korea Information Processing Society
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• v.6 no.4
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• pp.977-987
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• 1999

The current traffic signal control systems are operated depending on the pre-planned control scheme or the selected control scheme according to a period of time. The problem with these types of traffic control systems is that they can not cope with variant traffic flows appropriately. Such a problem can be difficult to solve by using binary logic. Therefore, in this 0paper, we propose a traffic signal control system which can deal wit various traffic flows quickly and effectively. The proposed controller is operated under uncertainty and in a fuzzy environment. It show the congestion of road traffic by using fuzzy logic, and it determines the length of green signal by means of a fuzzy inference engine. It modeled using petri-net to verify its validation.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.4
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• pp.48-62
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• 2023

Recently, smart intersections have been installed in many intelligent transportation system projects, but few cases use them for traffic signal operations besides traffic volume collection and statistical analysis. In order to respond to chronic traffic congestion, it is necessary to implement efficient signal operations using data collected from smart intersections. Therefore, this study establishes a procedure for operating a real-time traffic signal control algorithm using smart intersection data for efficient traffic signal operations and improving the existing algorithm. Effect analysis confirmed that intersection delays are reduced and the section speed improves when the offset is adjusted.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1375-1378
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• 1997

In this paper, we presents the algorithm which is to recognize the traffic sign on the road the traffic signal in a video image for autonomous navigation. First, the rocognition of traffic sign on the road can be detected using boundary point estimation form some scan-lines within the lane deducted. For this algorithm, index matrix method is used to detemine what sign is. Then, the traffic signal recognition is performed by usign the window minified by several scan-lines which position may be expected. For this algoritm, line profile concept is adopted.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.66-66
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• 2000

In this parer, we introduce an algorithm to control flows of the traffic in multi-intersections. It is pointed out that the main problem in traffic control is how to resolve the congested situations for the particular time-durations and directions. The heavy load to a certain direction usually leads the intersection to congested situations, and the adjacent intersections are affected. We control and analyze the traffic flow of multi-intersections consisting of five intersections, in which four intersections are linked to the four directions of the central one. The entrance of vehicles of each direction is described using the concept of probability. We compare the performance of the pretimed signal controls to the traffic adaptive signal controller using a Petri Net simulation tool, Exspect.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.5
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• pp.49-58
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• 2010

The traffic signal controllers being used in the domestic currently are being manufactured based on the korean national police standard which was developed for controlling the quad-light traffic signal having the red, yellow, left-turn arrow, and green lights. But according to the national policy for the traffic operation, they have to be changed to be able to switch the tri-light signal having red, yellow and green lights. In this study, a new tri-light traffic signal controller was designed and developed by the way improving the Signal Control Unit of the existing quad-light standard traffic controller. The Load Signal Unit(LSU) was improved to output 6 signals which are the two assemblies of three signal indications having the red, yellow, and green lights. To enough traffic signals output to control each directional movements and the various transport modes which are car, bus, bike, and pedestrian etc., the connector bus system was designed to be able to accommodate maximum 96 signals outputs being constructed by 16 LSUs. Flasher device was developed to be able to support maximum 32 red signals. In the software, the communication protocol between traffic control center and the traffic signal controller was improved and new signal map code values were defined for the developed LSU controlling the quad-light traffic signal. A model of the quad-light traffic signal controller developed and was tested three operations, protocol-operation, remote-command and control-mode. The test result operated all of them successfully.

• 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.

• 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.31-43
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• 2006

As of March 2005, the standard of traffic signal controllers became effective. The standard presents specifications and functions of a traffic signal controller which collects traffic information, sends it to the traffic control center, and controls traffic signal with adequate traffic signal timing provided by the traffic control center. Since the controllers by the previous standard lack parts compatibility and have different control functions and communication protocol, the maintenance cost has been increased. Also, some important functions like conflict detection have not worked out perfectly. To overcome these disadvantages, first of all, this standard secures hardware compatibility. Conflict detection method has been enhanced. Communication protocol to the traffic control center was included in the standard. With this standard, independent maintenance system and prompt treatment of hardware malfunctions becomes possible. Also, the unified intersection traffic control method will increase traffic safety.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.6
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• pp.77-90
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• 2015

An increasing number of vehicles is causing various traffic problems such as chronic congestion of highways and air pollution. Local governments have been managing traffic by constructing systems such as Intelligent Transport Systems (ITS) and Advanced Traffic Management Systems (ATMS) to relieve such problems, but construction of an infrastructure-based traffic system is insufficient in resolving chronic traffic problems. A more sophisticated system with enhanced operational management capabilities added to the existing facilities is necessary at this point. As traffic patterns of the urban traffic flow is time-specific due to the different vehicle populations throughout the time of the day, a local network-wide signal operation plan that can manage such situation-specific traffic patterns is deemed to be necessary. Therefore, this study is conducted for the purpose of establishment of a plan for contextual signal control management through signal optimization at the network level after setting the Frame Signal in accordance to the traffic patterns gathered from the short-term traffic forecast data as a means to mitigate the problems with existing standardized signal operations.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1504-1507
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• 1997

In this paper, we investigate a traffic flow modeled by stochastic Petri nets. The model consists of two parts : the traffic flow model and signal controller model. These models are used for analyzing the flow of the traffic intersection. The results of the evaluation are derived from a Petri Net-based simulation package, Greatspn. Through simulation we compare the performances of the pretimed signal controller with those of the trafic-adaptive signal controller.

• Journal of the Korea Society for Simulation
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• v.14 no.3
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• pp.79-90
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• 2005

There are plenty of optimization models for the signal-system of a single intersection and area traffic. Some of those models are adopted for the real traffic signal control system. The simulators for a single crossroad have been developed, so that we could evaluate optimization models and traffic control systems. However, the simulators for the area traffic are still being developed. Therefore, there are many limitations in the analysis and evaluation for area traffic control system. The area traffic is consisted of several intersections which are very complicated and many traffic strategies are adopted for the control system. This paper features an effective area traffic control system based on the High Lever Architecture(HLA). In this paper, we discuss the design of HLA-based area traffic control simulation. We describe technical motivations for the HLA, the key elements of the architecture and how they are minimum and essential to the goal of reuse and interoperability. A distributed simulation with HLA/RTI provides stable and satisfactory experimental results. Moreover, the prototype traffic control system provides reliable accomplishment compared to the NETSIM and TRANSYT-7F models.