• 제목/요약/키워드: Traffic control

검색결과 2,919건 처리시간 0.032초

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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    • 제30권2호
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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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    • 제2권1호
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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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    • 제32권4호
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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.

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

  • 윤명오;이철영
    • 한국항해학회지
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    • 제15권3호
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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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인터넷 응용 4지교차로제어에 관한 연구 (A Study on the Internet based Traffic Intersection Control)

  • 진현수
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2008년도 춘계학술발표논문집
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    • pp.245-247
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    • 2008
  • 교차로 교통시스템은 도로상에 깔린 루프검지기를 통해서 통과차량과 지체차량의 수를 누적하여 차량 통행주기를 결정하는 웹스터방정식의 방법을 따른다. 그러나 웹스터방정식은 현장 교차로상의 교통데이터를 주로 사용하는 방법이라 할 수 있으므로 이웃 교차로의 교통상황을 데이터로 받아서 교차로 연동제어를 할 수 없는 문제점을 갖고 있다. 따라서 교차로 원격지 제어를 시행 할 경우에 마땅한 제어 방법이 없고, 있어도 지역네트워크 단위인 고비용 시스템을 사용하여야 하므로 경제성이 없다. 따라서 인터넷을 사용하여 이웃 및 먼거리에 떨어져 있는 교차로의 교통상황을 참조하여 교차로 교통제어를 할 경우에는 저비용의 전문성 있는 교차로 교통제어를 할 수 있다.

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

  • 이명섭;박창현
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 하계종합학술대회 논문집 I
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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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교통신호의 자동최적제어에 관한 연구 (Automatic Optimum Control of the Traffic Signal Lights)

  • 양흥석;김호윤
    • 전기의세계
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    • 제20권4호
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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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영상에서 객체 추출을 통한 적응형 통행 우선순위 교통신호 제어 시뮬레이션 (Simulation of Traffic Signal Control with Adaptive Priority Order through Object Extraction in Images)

  • 윤재홍;지유강
    • 한국멀티미디어학회논문지
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    • 제11권8호
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    • pp.1051-1058
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    • 2008
  • 영상처리와 통신 기술의 진보는 통합된 시스템의 일부분으로써 긴급 차량 우선권과 통행 우선 방법 모두를 수용하기 위한 현행 교통 신호 제어기들과 차량 탐지 기술을 가능하게 만들고 있다. 횡단보도에서 현행 교통 신호제어는 고정된 신호 주기에 따라 변하도록 구성되어 있다. 고정된 신호 주기의 신호제어 체계는 통행량이 없는 상황에서도 일정한 신호주기가 주어지기 때문에 상대적으로 교통량이 많은 곳에서는 해당 진행 신호가 부여될 때까지 대기해야 한다. 이러한 대기 시간은 신호 위반에 따른 교통사고의 위험과 교통체증을 유발하게 된다. 본 논문에서는 교통사고의 위험과 교통 체증을 해소하기 위한 방안으로 객체 검출영상을 통하여 현장상황에 맞게 우선적으로 신호가 부여될 수 있도록 적응형 우선순위 교통신호 제어 시스템을 설계하고 시뮬레이션 하였다.

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

  • 서강도;조진호
    • 대한전자공학회논문지TC
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    • 제45권2호
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    • pp.26-36
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    • 2008
  • 현재 우리나라에는 최첨단의 정보통신 서비스를 제공을 목적으로 ubiquitous city(u-City)가 건설 중에 있다. 이들 도시에서 ITS(Intelligent Transportation Systems)는 도시거주민들에게 적절한 교통정보를 제공하는 동시에 최적으로 도시교통을 제어하는 방안이다. ITS의 한 부분으로서 교통흐름에 적합한 교통신호제어가 필요하며 이를 위해 많은 교통정보를 실시간으로 수집하여야 한다. 이러한 교통정보의 수집은 도시운영을 위하여 최첨단 정보통신 서비스가 제공되는 u-City에서는 어렵지 않을 것이다. 이러한 미래지향적인u-City의 ITS 교통제어에 적합한 새로운 시스템에 대하여 이 논문에서는 연구하였다.

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

  • 유선희;엄정애
    • 대한가정학회지
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    • 제42권9호
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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.