• Proceedings of the Korean Information Science Society Conference
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• 1999.10b
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• pp.122-124
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• 1999

날로 심각한 도시문제가 되고 있는 교통문제를 효과적으로 해결하기 위해서는 교통체증을 정확하게 진단해서 교통망의 효율을 최대로 높일 수 있도록 교통 신호체계를 수립하는 것이 요구되며, 이것을 위해서는 실시간으로 변화되는 교통류에 적절히 대응할 수 있도록 원활한 교통 신호체계를 최적화하는 것이 필요하다. 본 연구에서는 실시간으로 변화되는 교통류에 대응해서 원활한 교통소통을 위한 신호조정의 문제를 다수의 신호등을 대상으로 가능한 서로 다른 여러 신호조정의 조합들 중 최적안을 찾는 최적화 문제로 보았다. 본 논문에서는 휴리스틱 탐색기법을 이용하여 교통류의 변화에 따라 최적의 교통 신호체계를 수립할 수 있는 교통 신호체계 최적화 시스템을 제시하고, 부산광역시 부전동 일대의 12개 교차로를 포함하는 교통망에 대한 교통정보를 바탕으로 실험해봄으로써 실시간 적용가능성을 보여준다.

• Journal of Korean Society of Transportation
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• v.25 no.2 s.95
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• pp.109-120
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• 2007

This study developed a methodology that can reflect more realistic traffic flow to understand platoons on highways. The understanding of the phenomenon nay secure highway safety and authoritative credibility in highway planning. In this study platoons generated by 'random effects' of cars are modeled, and this model is validated using a real data set acquired from the Jayu Expressway in Kyonggi Province, Korea.

• Journal of Korean Society of Transportation
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• v.22 no.7 s.78
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• pp.61-67
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• 2004

It is needed for one to design the better models estimating emission and then with the real time data, make the monitoring system simulating emission rate because of having built the basement of accepting real-time traffic information in ITS projects. The objective of the study is to develop the monitoring system visualizing air pollution to a certain place. It is based on the estimated emission from the patterns of individual vehicles and the changes of traffic flow. For constructing simulator, we loaded referring algorithm in actuality program and simulates the traffic flow movement in a microscopic viewpoint. The simulator is able to express not only the movement of each car but also to visualize processing the emission and diffusion of the air pollutant by computer program. Not only expresses the simulation process the angle of vision but it also cutting down environment expenses and improving the traffic impact assessment and the traffic impact assessment.

• Journal of Korean Society of Transportation
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• v.17 no.1
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• pp.187-196
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• 1999

The increasing interest in the use of Automated Speed Enforcement (ASE) systems in Korea enables to enforce speed violation by National Police Agency. We have analyzed the mechanism of ASE systems on traffic safety throughout Korea. 1 The data collected on a 2km road-section of each 32 ASE stations during one rear period indicate significant safety improvement. The results were (a) a decrease in the total number of accidents of 28%, (b) a decrease in the number of fatalities of 60%. 2. The study also that ASE systems are effective to reduce average speed, speed variance, and short headway. 3. Based on the operational data collected at 15 locations, an aggregate safety prediction model is proposed as a multiple regressions form. The primary operational variables that appear to affect the frequencies of accident are : average speed, speed variance, and the number of vehicles exceeding 30km/h of posted speed limit.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.6 no.3
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• pp.57-66
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• 2007

Weaving is defined as the crossing of two or more traffic streams traveling in the same general direction along a significant length of highway without the aid of traffic control devices. Compared with other freeway sections, perturbation is easy to happen at weaving section. Because there are a lot of lane-changing maneuvers at the weaving section, traffic is subject to turbulence in excess of that normally presents on freeway basic section. This turbulence causes operational problems and its impact must be considered. The purpose of this paper is to perform a basic study on flow characteristics by lane, which can be achieved through analyzing breakdown phenomenon in the microscopic approach. The study made use of data derived from the aerial photography for the microscopic analysis. This research produced the 30-second interval data such as flows, speeds, and densities for the macroscopic analysis and derived the vehicular data to draw time-space diagram for the microscopic analysis. The paper analyzed the traffic characteristics using flows, speeds and densities variation and investigated the conditions of breakdown occurrence with the time-space diagrams. The breakdown phenomenon was identified at weaving section and the propagation from free flow to synchronized flow was observed in this study. In the future, the findings help develop the traffic operational algorithm to manage the traffic congestion under ubiquitous circumstance since the conditions of breakdown Phenomenon can be understood more.

• Journal of Korean Society of Transportation
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• v.34 no.3
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• pp.278-290
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• 2016

Maximum traffic flow rate is an important performance measure of operational status in transport networks, and has been considered as a key parameter for transportation operation since a bottleneck in congestion decreases maximum traffic flow rate. Although previous studies for traffic flow analysis have been widely conducted, a detection method for changes in dynamic traffic flow has been still veiled. This paper explores the dynamic traffic flow detection that can be utilized for various traffic operational strategies. Turning point analysis (TPA), as a statistical method, is applied to detect the changes in traffic flow rate. In TPA, Bayesian approach is employed and vehicle arrival is assumed to follow Poisson distribution. To examine the performance of the TPA method, traffic flow data from Jayuro urban expressway were obtained and applied. We propose a novel methodology to detect turning points of dynamic traffic flow in real time using TPA. The results showed that the turning points identified in real-time detected the changes in traffic flow rate. We expect that the proposed methodology has wide application in traffic operation systems such as ramp-metering and variable lane control.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.05a
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• pp.1-2
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• 2019

일반적인 해상교통 분석 방법은 대상 항만의 항적 데이터를 기반으로 데이터를 추출한 후 모델을 구축하며, 구축된 모델을 바탕으로 해상교통 현상을 재현하고 있지만, 이러한 방법은 항로 혹은 통항량 변동 등의 변화에 따른 교통류를 예측할 수 없어 그 활용에 제약이 많다. 본 논문에서는 기존의 해상교통 분석 사례를 통해 교통 특성 모델의 요소를 식별하고, 이를 동적인 해상교통 환경을 시뮬레이션 할 수 있는 에이전트 기반의 교통류 생성 기술 개발의 기초 자료로 활용하고자 한다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.2
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• pp.60-66
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• 2009

The acceleration noise is valuable index to monitor traffic stability. However, the previous study was performed for the acceleration noise of individual vehicle. The consideration of the acceleration noise for vehicle in the network has not been studied yet. This paper proposes a new macroscopic traffic flow monitoring method based on applying network acceleration noise.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.6
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• pp.761-767
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• 2012

Maritime traffic assessment is important to understand the characteristics of maritime traffic and to prevent maritime accidents. The maritime traffic assessment can be calculated from the ship trajectory data observed by using AIS(Automatic Identification System). This paper developes a maritime traffic assessment tool using ship's position and speed, course, time data from ships navigating waterways. The results are represented in terms of the number of traffic quantity and traffic distribution, speed distribution, geometric collision candidates. The developed tool will contributes to advance maritime traffic safety by VTS(Vessel Traffic Services).

• 한국ITS학회:학술대회논문집
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• 2008.11a
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• pp.37-45
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• 2008