• International Journal of Highway Engineering
• /
• v.14 no.5
• /
• pp.145-155
• /
• 2012

PURPOSES: This study proposes a novel method based on microscopic simulation models to evaluate bicycle passing ways in mixed traffic flow conditions at signalized intersections. METHODS: Both operational efficiency and safety are taken into consideration in the evaluation. A widely used performance measure, delay, is used for evaluating the operational efficiency. Regarding the safety evaluation, surrogate safety measures (SSM) to represent traffic conflicts and the level of crash severity, DeltaS and Max.DeltaV, are applied in the proposed method. RESULTS: Extensive simulations and statistical tests show that an integrated bike-box way is identified as the best in terms of operational efficiency and safety. CONCLUSIONS: The proposed method and outcomes of this study will be valuable for bicycle traffic operations and facility design.

• Journal of Communications and Networks
• /
• v.14 no.3
• /
• pp.310-318
• /
• 2012

Detecting intrusion attacks accurately and rapidly in wireless networks is one of the most challenging security problems. Intrusion attacks of various types can be detected by the change in traffic flow that they induce. Wireless industrial networks based on the wireless networks for industrial automation-process automation (WIA-PA) standard use a superframe to schedule network communications. We propose an intrusion detection system for WIA-PA networks. After modeling and analyzing traffic flow data by time-sequence techniques, we propose a data traffic prediction model based on autoregressive moving average (ARMA) using the time series data. The model can quickly and precisely predict network traffic. We initialized the model with data traffic measurements taken by a 16-channel analyzer. Test results show that our scheme can effectively detect intrusion attacks, improve the overall network performance, and prolong the network lifetime.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.20 no.43
• /
• pp.91-97
• /
• 1997

The objective of a traffic management system is to promote safe driving, low pollution, short travel time, and optimized traffic flow by naturally distributing the flow of traffic through the use of suitable telecommunications media. Such traffic management systems will be improved by integrating dynamic traffic data and two-way communication media because cars can work as sensors. The purpose of this paper is to help organizations trying to select the correct telecommunications media for minimal-cost investment options without loss of functionality. The wireless communications for an intelligent transportation system (ITS) are introduced in this paper. We describe which kind of telecommunication media are suitable. FM broadcast type media or cellular phone can be recommended to provide real time traffic and roadway conditions in the first stage of ITS, because existing broadcast base station or cellular network facilities can be used. It is expected that cellular radio network or satellites are used for communication. Finally, the strategy and deployment plan of an ITS are described based on selections of telecommunication media in Korea.

• Journal of the Korean Society of Safety
• /
• v.25 no.2
• /
• pp.89-94
• /
• 2010

This study deals with the traffic accident according to the improvement projects of frequent accident locations. The objective is to analyze the impact of improvements on the accident reduction. In pursuing the above, the study gives the particular attentions to developing the models based on the data of 70 intersections improved. The main results analyzed are as follows. First, 4 multiple linear regression accident models(total, side right-angle, rear end and side stripe accident) which were statistically significant were developed. Second, total accidents reduction by sight-distance and turning traffic flow improvements, side right-angle by sight-distance, over-speed and lane operation, rear end by turning traffic flow, signal and lane operation, and side stripe by traffic impedance improvements were analyzed. Finally, the above 4 models were evaluated to be statically significant through the correlation analysis and pair-sample t-test.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2013.06a
• /
• pp.515-517
• /
• 2013

We carried out the maritime safety audit for Sandal Water Bridge constructed between Geje-Do and Sandal-Do in 2015. To study as to whether can be secured the marine traffic safety for this area, this research investigated and performed the marine accident, marine traffic volume, the marine traffic flow simulation and shiphandling simulation. It is considered to be required the quantitative guidelines for maritime safety audit including audit target area and formal audit object etc.

• Journal of Korean Society of Transportation
• /
• v.17 no.2
• /
• pp.115-126
• /
• 1999

Past nears many Studies have been described for present state and forecasted for the future phenomena in various areas. Many theories and methodologies in transportation have been developed and applied by researchers and planners. On the other hand, many theories and methodologies had disappeared caused by their critical limitations. One of this cause that was discovered of the Chaos in traffic flows. The occurrence of Chaos in traffic flows has affected to the traffic volume and decreased significancy of a simulation result of a specific traffic flow. According to this fact, long-term forecast of traffic flow is difficult, moreover a butterfly effect impedes development and establishment of transportation model. A methodology to solve Chaos character in traffic flow can be able to provide more effective transport planning. This study tackles to enhance and revise the existing theories for the traffic flow applying Chaos theory to estimating travel time.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.25 no.8A
• /
• pp.1169-1176
• /
• 2000

In this paper, label assignment schemes considering the IP flow model for the efficient MPLS traffic engineering are proposed and evaluated. Based on the IP flow model, the IP flows are classified into transient flows and base flows. Base flows, which last for a long time, transmit data in high bit rate, and be composed of many packets, have good implications for the MPLS traffic engineering, because they usually cause network congestion. To make use of base flows for the MPLS traffic engineering, we propose two base flow classifiers and label assignment schemes where transient flows are allocated to the default LSPs and base flows to explicit LSPs. Proposed schemes are based on the traffic-driven label triggering method combined with a routing tabel. The first base flow classifier uses both flow size in packet counts and routing entries, and the other one, extending the dynamic X/Y flow classifier, is based on a cut-through ratio. Proposed schemes are shown to minimize the number of labels, not degrading the total cut-through ratio.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.22 no.6
• /
• pp.77-91
• /
• 2023

Recently, there has been a worldwide increase in research and development on automated vehicles for commercialization. It is expected that the use of level 3 autonomous vehicles on continuous-flow roads will be introduced and will increase. Consequently, various studies have been conducted to investigate the impact of mixed traffic flow with automated vehicles based on the market penetration rate (MPR). However, these studies have been conducted independently, and the results have shown different trends. Therefore, this study attempted a quantitative analysis of the impact of automated vehicles on mixed traffic flow on uninterrupted roads through a meta-analysis. The results showed that the effect size estimated from an MPR of 75% or higher was statistically significant.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.13 no.4
• /
• pp.1-11
• /
• 2014

Traffic congestion cost is more likely to occur in the inner city than interregional road, and it accounts for about 63.39% of the whole. Therefore, it is important to mitigate traffic congestion of the inner city. Traffic congestion in the urban could be divided into Recurrent congestion and Non-recurrent congestion. Quick and accurate detection of Non-recurrent congestion is also important in order to relieve traffic congestion. The existing studies about incident detection have been variously conducted, however it was limited to Uninterrupted Traffic Flow Facilities such as freeway. Moreover study of incident detection on the interrupted Traffic Flow Facilities is still inadequate due to complex geometric structure such as traffic signals and intersections. Therefore, in this study, incident detection model was constructed using by Artificial Neural Network to aim at urban arterial road that is interrupted traffic flow facility. In the result of the reliability assessment, the detection rate were 46.15% and false alarm rate were 25.00%. These results have a meaning as a result of the initial study aimed at interrupted traffic flow. Furthermore, it demonstrates the possibility that Non-recurrent congestion can be detected by using car navigation data such as car navigator system device.

• Proceedings of KOSOMES biannual meeting
• /
• 2018.06a
• /
• pp.49-49
• /
• 2018