• Proceedings of the Korean Operations and Management Science Society Conference
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• 한국경영과학회 2003년도 추계학술대회 및 정기총회
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• pp.15-18
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• 2003

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 systems. The area traffic is consist of several intersections interconnected which are very complicated and many traffic strategy are adopted for the control system. This paper features an effective area traffic control system by High Lever Architecture(HLA) which is a new developed simulation tool. 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.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• 제20권5호
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• pp.100-112
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• 2021

With the advent of big data, traffic prediction has been developed based on historical data analysis methods, but this method deteriorates prediction performance when a traffic incident that has not been observed occurs. This study proposes a method that can compensate for the reduction in traffic prediction accuracy in traffic incidents situations by hybrid approach of machine learning and traffic simulation. The blind spots of the data-driven method are revealed when data patterns that have not been observed in the past are recognized. In this study, we tried to solve the problem by reinforcing historical data using traffic simulation. The proposed method performs machine learning-based traffic prediction and periodically compares the prediction result with real time traffic data to determine whether an incident occurs. When an incident is recognized, prediction is performed using the synthetic traffic data generated through simulation. The method proposed in this study was tested on an actual road section, and as a result of the experiment, it was confirmed that the error in predicting traffic state in incident situations was significantly reduced. The proposed traffic prediction method is expected to become a cornerstone for the advancement of traffic prediction.

• Transactions of the Korean Society of Automotive Engineers
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• 제12권5호
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• pp.136-145
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• 2004

In companion paper, the composition and structure of the traffic environment is derived. Rules to regulate agent behaviors and the frameworks to communicate between the agents are proposed. In this paper, the model of a driver agent which controls a vehicle agent is constructed. The driver agent is capable of having different driving styles. That is, each driver agent has individual behavior settings of the yielding index and the passing index. The yielding index can be defined as how often the agent yields in case of lane changes, and the passing index can be defined as how often the agent passes ahead. According to these indices, the agents overtake or make their lanes for other vehicles. Similarly, the vehicle agents can have various vehicle dynamic models. According to their dynamic characteristics, the vehicle agent shows its own behavior. The vehicle model of the vehicle agent contains the nonlinear subcomponents of engine, torque converter, automatic transmission, and wheels. The simulation has proceeded for an interrupted flow model. The result has shown that it is possible to express the characteristics of each vehicle and its driver in a traffic flow, and that the change of the traffic state is closely related with the distance and the signal delay between intersections. The system developed in this paper shows the effectiveness and the practical usefulness of the traffic simulation.

• International Journal of Highway Engineering
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• 제17권4호
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• pp.117-126
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• 2015

PURPOSES : This study aims to investigate the direct and indirect influence areas from incidents on urban interrupted roadways and to develop traffic management strategies for each influence area. METHODS : Based on a literature review, various traffic management strategies for certain incidents were collected. In addition, the relationship between the measure of effectiveness and the characteristics of incidents was explored using an extensive simulation study. RESULTS : From the simulation studies, traffic delays increased as the number of lane closures increased, and the impact of lane closures was reduced to the direction upstream from the incident site. However, the magnitude of the delay change depended on the degree of saturation. Using these characteristics, the direct and indirect influence areas resulting from incidents were defined, and traffic management strategies were established for each direct and indirect influence area and for each level of incident. CONCLUSIONS: The results of this study will contribute to the improvement of national traffic safety by preventing secondary incidents and by effective adaptation to incident events.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• 제9권6호
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• pp.63-82
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• 2010

In spite of continuous road construction, traffic congestion has been worsening by radical vehicle's increase and development of surroundings near expressway. Thus, the necessity of traffic management and the needs of provision of traffic information to drivers are raised. In order to solve traffic problems, such as traffic congestion, search for optimal congestion management technique and evaluation of the effect of optimal solution should be examined prior to practice of optimal alternative. However, existing traffic analysis model and simulation programs as tools to search and evaluate optimal alternative are not sufficient to reflect traffic flow characteristics, domestic road and traffic conditions and to link up to Freeway Traffic Management Systems (FTMS). Hence, to use existing traffic analysis and simulation tools are followed by hard work to need a lot of time and cost. Therefore, in this research, Expressway TRaffic Analysis Model (ExTRAM) based on Freeway Traffic Management Systems (FTMS) was developed to apply it into congestion management easily.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• 제12권8호
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• pp.581-588
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• 2002

Precise highway traffic noise simulation and reduction require the accurate data for sound power levels omitted by vehicles, varied to road surface, traffic speed, vehicle types and makers, different from countries to countries. In this study, we have elaboratively measured Korea highway traffic noise and parameters affecting noise levels at the nearside carriageway edge. From numerical simulation using the measured results for highway traffic noise, we propose not only two correction factors to enhance the accuracy of Korea highway traffic sound power estimation using ASJ Model-1998 but also its typical power spectrum according to road surface type. The measured and predicted highway traffic noise levels using the proposed sound power show little difference within 1 dB.

• Journal of computational fluids engineering
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• 제11권4호
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• pp.20-25
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• 2006

In the present study, flow characteristics inside a road tunnel are simulated for the ventilation flows due to jet fan system and flows induces by the traffic. Traffic ventilation is numerically simulated by multiple reference frame. From the results of steady state simulation of tunnel ventilation, it is found that the proper ventilation is achieved by the designed jet fan system along with ventilating flow induced by the traffic. A transient simulation is also performed for the case of vehicle fire in the tunnel reversing the direction of rotation of some fans. The results suggest that the heat and smoke can be controlled by the proper changing of fan operation mode. The present results can be used to design proper ventilation system and effective smoke control system as well.

• Journal of Auto-vehicle Safety Association
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• 제15권2호
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• pp.21-27
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• 2023

This paper presents a simulation tool for developing and evaluating automated driving systems' lane change algorithm in urban congested traffic. The behavior of surrounding vehicles was modeled based on driver driving data measured in urban congested traffic. Surrounding vehicles are divided into aggressive vehicles and non-aggressive vehicles. The degree of aggressiveness is determined according to the lateral position to initiate interaction with the vehicle in the next lane. In addition, the desired velocity and desired time gap of each vehicle are all randomly assigned. The simulation was conducted by reflecting the cognitive limitations and control performance of the autonomous vehicle. It was possible to confirm the change in the lane change performance according to the variation of the lane change decision algorithm.

• Journal of Korea Society of Digital Industry and Information Management
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• 제5권3호
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• pp.107-115
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• 2009

Traditionally, simulation method is used to test and evaluate the performance of communication protocol or functional elements for mobile communication service. In this paper, wireless network simulator is implemented using the C++ object-oriented programming language. This simulator can simulate wireless data services, like as ad-hoc networks, by considering the user's mobility. In this paper, the simulator includes network traffic model to reflect wireless data service and traffic source model to represent a user's mobility similar to real service environment and traffic characteristics can be reflected on the simulation, and also more accurate simulation results can be got through that. In addition, by using object-oriented techniques, new service feature or environment can be easily added or changed so that the developed mobile communication simulator can reflect the real service environment all the time. This simulator can be used in adjusting the characteristics of wireless data hosts following the mobility of the user, and also can be used in building new wireless ad-hoc network routing protocols.

• The Transactions of the Korean Institute of Electrical Engineers P
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• 제62권3호
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• pp.111-116
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• 2013

Noise problem that occurs on the road is raising a lot of problems in the economic, social and environmental aspects. The objective of this paper is to propose ANC(active noise cancellation)-based road traffic noise reduction algorithm-model which can reduce noise by generating frequency opposed to noise sources to improve and complement the problem that existing physical form of a noise barrier. In this paper, we measured the noise characteristic from collection of two difference car noise also ANC simulation has been performed by using road traffic noises input. In order to compare the control performance, we performed noise reduction simulation of ANC by filtered-X LMS algorithm and delayed control signal injection. As a result of this simulation, we confirmed that convergence performance and noise decrease effect to the filtered-X LMS algorithm by inputting the road traffic noise.