• Title/Summary/Keyword: Traffic control

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Scalable Network Architecture for Flow-Based Traffic Control

  • Song, Jong-Tae;Lee, Soon-Seok;Kang, Kug-Chang;Park, No-Ik;Park, Heuk;Yoon, Sung-Hyun;Chun, Kyung-Gyu;Chang, Mi-Young;Joung, Jin-Oo;Kim, Young-Sun
    • ETRI Journal
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    • v.30 no.2
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    • pp.205-215
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    • 2008
  • Many control schemes have been proposed for flow-level traffic control. However, flow-level traffic control is implemented only in limited areas such as traffic monitoring and traffic control at edge nodes. No clear solution for end-to-end architecture has been proposed. Scalability and the lack of a business model are major problems for deploying end-to-end flow-level control architecture. This paper introduces an end-to-end transport architecture and a scalable control mechanism to support the various flow-level QoS requests from applications.

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Performance Analysis of ABR Congestion Control Algorithm using Self-Similar Traffic

  • Kim, Dong-Il;Jin, Sung-Ho
    • Journal of information and communication convergence engineering
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    • v.2 no.1
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    • pp.15-21
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    • 2004
  • One of the most important issues in designing a network and realizing a service is dealing with traffic characteristics. Recent experimental research on LAN, WAN, and VBR traffic properties has highlighted that real traffic specificities can not be displayed because the current models based on the Poisson assumption under estimate the long range dependency of network traffic and self-similar peculiarities. Therefore, a new approach using self-similarity characteristics as a real traffic model was recently developed. In This paper we discusses the definition of self-similarity traffic. Moreover, real traffic was collected and we generated self-similar data traffic like real traffic to background load. On the existing ABR congestion control algorithm transmission throughput with the representative ERICA, EPRCA and NIST switch algorithm show the efficient reaction about the burst traffic.

Traffic-induced vibrations at the wet joint during the widening of concrete bridges and non-interruption traffic control strategies

  • Junyong Zhou;Zunian Zhou;Liwen Zhang;Junping Zhang;Xuefei Shi
    • Computers and Concrete
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    • v.32 no.4
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    • pp.411-423
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    • 2023
  • The rapid development of road transport has increased the number of bridges that require widening. A critical issue in the construction of bridge widening is the influence of vibrations of the old bridge on the casting of wet joint concrete between the old and new bridges owing to the running traffic. Typically, the bridge is closed to traffic during the pouring of wet joint concrete, which negatively affects the existing transportation network. In this study, a newly developed microscopic traffic load modeling approach and the vehicle-bridge interaction theory are incorporated to develop a refined numerical framework for the analysis of random traffic-bridge coupled dynamics. This framework was used to investigate traffic-induced vibrations at the wet joint of a widened bridge. Based on an experimental study on the vibration resistance of wet joint concrete, traffic control strategies were proposed to ensure the construction performance of cast-in-site wet joint concrete under random traffic without interruption. The results show that the vibration displacement and frequency of the old bridge, estimated by the proposed framework, were comparable with those obtained from field measurements. Based on the target peak particle velocity and vibration amplitude of the wet joint concrete, it was found that traffic control measures, such as limiting vehicle gross weight and limiting traffic volume by closing an additional traffic lane, could ensure the construction performance of the wet joint concrete.

A Study on Optimum Control of Marine Traffic(II) - In the Domain of Passage - (해상 교통량의 효율적 관리 방안에 관하여 (II) - 일반 수로의 경우 -)

  • 윤명오;이철영
    • Journal of the Korean Institute of Navigation
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    • v.15 no.3
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    • pp.1-11
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    • 1991
  • As increasing needs of marine transportation , world merchant fleet and ship's size were enlarged and it caused frequent disasters in human lives and natural environment. By the reason of the above, they started to establish the Vessel Traffic System (VTS) at the European coast in 1960' and most of advanced contries established and managed it to prevent the sea traffic accidents in these days. The concept of traffic control at sea can be divided into three types. First, the initial gathering of informations about ship's identity and movement etc.. Second, monitoring of the traffic flow and amendment of instructions. Third , organization and direction of ships by allocating routes and speeds. Where the goal of traffic control is safety of traffics and developing effectiveness of navigation channel, if traffic volume is less tan channel capacity then the above first or second level of control would be sufficient but if it is bigger than that , more positive policy of control should be adopted as same as third type of the above. In this paper where the strategy of VTS is focused on the control of traffic density to be spread equality, as possible , all over the navigation channels and also improvement of effectiveness , it suggests algorithm to assign the vessels to the channels with balanced traffic density , and other algorithms using D.P. to sequence the vessels assigned to one channel in optimum order which decreases the mean waiting time in sense of channel effectiveness with numerical examples.

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A Study on the Internet based Traffic Intersection Control (인터넷 응용 4지교차로제어에 관한 연구)

  • Jin, Hyun-Soo
    • Proceedings of the KAIS Fall Conference
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    • 2008.05a
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    • pp.245-247
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    • 2008
  • Traffic intersection conrol is implemented by the data which is acquired to vechile Loop detector. Traffic intersection control equation is Webster equation, which use passing and delayed vechile number. But webster equation is applied to the spot traffic intersection, it is not used to related traffic intersection network system. There is not the approprate remote traffic intersection control, even if there is, it is high cost local network system. Therefore low cost and expert traffic intersection control is realized by internet referencing next and distant intersection traffic information.

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A traffic control agent to manage flow usage in Differentiated Service Network (차별화서비스 네트워크에서 흐름 관리를 위한 트래픽 제어 에이전트)

  • 이명섭;박창현
    • Proceedings of the IEEK Conference
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    • 2003.07a
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    • pp.69-72
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    • 2003
  • This paper presents a traffic control agent that can perform the dynamic resource allocation by controlling traffic flows on a DiffServ network. In addition, this paper presents a router that can support DiffServ on Linux to support selective QoS in IP network environment. To implement a method for selective traffic transmission based on priority on a DiffServ router, this paper changes the queuing discipline in Linux, and presents the traffic control agent so that it can efficiently control routers, efficiently allocates network resources according to service requests, and relocate resources in response to state changes of the network.

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Automatic Optimum Control of the Traffic Signal Lights (교통신호의 자동최적제어에 관한 연구)

  • 양흥석;김호윤
    • 전기의세계
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    • v.20 no.4
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    • pp.12-16
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    • 1971
  • The electrical detector and computer systems for traffic flow and speed measurement are demonstrated in this paper. For the best traffic control optimization, linear and non-linear equations in the transition state are dealing with the perturbation of the linear car-following. In the conclusions, we construct a realizable system for the central automatic traffic control with a computer. Furthermore, fixed periodic switching system by manual with the automatic traffic control system is recommended for emergency perturbation.

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Simulation of Traffic Signal Control with Adaptive Priority Order through Object Extraction in Images (영상에서 객체 추출을 통한 적응형 통행 우선순위 교통신호 제어 시뮬레이션)

  • Youn, Jae-Hong;Ji, Yoo-Kang
    • 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.

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An approach for Traffic Signal Control using RFID in the u-City (u-City에서 RFID를 이용 교통신호제어에 관한 연구)

  • Seo, Gang-Do;Cho, Jin-Ho
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.45 no.2
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    • pp.26-36
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    • 2008
  • This study proposed a traffic responsive urban traffic control system using RFID(Radio Frequency Identification) technology to get traffic information. The proposed system is a decentralized control using model predictive control. The objective of proposed system is to get traffic data using advanced technology for controlling the junctions' traffic rights. A simulation example is provided to demonstrate the applicability of the proposed model.

The Effects of Traffic Safety Education by Integrated Activies on Children′s Traffic Safety Knowledge (통합적 교육활동을 통한 교통안전교육이 유아의 교통안전 지식에 미치는 영향)

  • Yoo Sun-Hee;Ohm Jung-Ae
    • Journal of the Korean Home Economics Association
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    • v.42 no.9
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    • pp.149-160
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    • 2004
  • This study investigated the effectiveness of traffic safety education by integrated activities on children's traffic safety knowledge. Subjects were 55 kindergarten children aged 5 years old. The subjects were divided into experimental and control groups. Traffic safety education by integrated activities were applied in the experimental group for 6 weeks. The traffic safety knowledge test was administered to the experimental and control groups for pre-test and post-test analyses. ANCOVA was carried out for both groups to verify the hypothesis of this study. There were statistically significant differences of the children's traffic safety knowledge score including walking, bike, and automobile between the experimental and control groups. To conclude, traffic safety education by integrated activities was very effective to increase children's traffic safety knowledge.