• Title/Summary/Keyword: Real time transport

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Real Time Macroscopic Traffic Flow Monitoring Using Acceleration Noise (가속소음을 활용한 실시간 거시 교통류 모니터링)

  • Eom, Ki-Jong;Lee, Chung-Won
    • 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.

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Required Video Analytics and Event Processing Scenario at Large Scale Urban Transit Surveillance System (도시철도 종합감시시스템에서 요구되는 객체인식 기능 및 시나리오)

  • Park, Kwang-Young;Park, Goo-Man
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.11 no.3
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    • pp.63-69
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    • 2012
  • In this paper, we introduced design of intelligent surveillance camera system and typical event processing scenario for urban transit. To analyze video, we studied events that frequently occur in surveillance camera system. Event processing scenario is designed for seven representative situations(designated area intrusion, object abandon, object removal in designated area, object tracking, loitering and congestion measurement) in urban transit. Our system is optimized for low hardware complexity, real time processing and scenario dependent solution.

Implementation of Message Service for TCN Protocol (전동차용 네트웍 프로토콜의 메세지 서비스의 구현)

  • Park, Hong-Sung;Jin, Chang-Ki;Park, Geun-Pyo;Kim, Hyung-Yuk;Yoon, Gun
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.133-133
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    • 2000
  • This paper implements Message Service of TCN or IEC 61375-1. TCN is divided into two services, Variable and Message Service. Variable Service uses the broadcasting method with Source Address, but Message Service uses peer-to-peer method with Destination Address and has OSI 7 Layer. In TCN, interface between Transport and Network Layer has not been defined and Meaning of Packet Pool has not been defined exactly. Therefore, this paper proposes the Implementation method for both the interface between Transport and Network Layer and the packet pool for Message Service of TCN.

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Test of Dynamic Pressurizer Model for CANDU Reactor System Simulation

  • Lee, S.H.;Lim, J.C.;Park, J-W.
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
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    • 1993.11a
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    • pp.103-108
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    • 1993
  • In nuclear power plants using pressurized water as the main coolant, it is necessary to maintain system pressure within operational range. During transients, the coolant shrinks and expands causing insurge and outsurge of coolant in the pressurizer. In CANDU system, the pressure is controlled mainly by the pressurizer/degasser-condenser system. In CANDU system, the control of heat transport system pressure is achieved by giving heat to the pressurizer by activating the heaters to compensate a diminution in pressure or by removing heat from the pressurizer by bleeding steam to the degasser-condenser to compensate an increase in pressure. This study aims at developing a theoretical model capable to simulate various operational transients in the CANDU primary heat transport system (PHTS), applicable to CANDU engineering simulator on real time basis.

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Accelerating the Sweep3D for a Graphic Processor Unit

  • Gong, Chunye;Liu, Jie;Chen, Haitao;Xie, Jing;Gong, Zhenghu
    • Journal of Information Processing Systems
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    • v.7 no.1
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    • pp.63-74
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    • 2011
  • As a powerful and flexible processor, the Graphic Processing Unit (GPU) can offer a great faculty in solving many high-performance computing applications. Sweep3D, which simulates a single group time-independent discrete ordinates (Sn) neutron transport deterministically on 3D Cartesian geometry space, represents the key part of a real ASCI application. The wavefront process for parallel computation in Sweep3D limits the concurrent threads on the GPU. In this paper, we present multi-dimensional optimization methods for Sweep3D, which can be efficiently implemented on the finegrained parallel architecture of the GPU. Our results show that the overall performance of Sweep3D on the CPU-GPU hybrid platform can be improved up to 4.38 times as compared to the CPU-based implementation.

Distributed Rate and Congestion Control for Wireless Mesh Networks

  • Quang, Bui Dang;Hwang, Won-Joo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.9A
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    • pp.916-922
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    • 2007
  • Wireless networks (WNs) are developed and applied widely in a lot of areas. Now, a new generation of wireless networks is coming, and that is Wireless Mesh Network (WMN). At present, there are not so many researches which deal on this area. Most researches are derived from Mobile Ad hoc Networks (MANET) and WNs. In WMNs, there are some applications that require real-time delivery. To guarantee this, rate control and congestion control are needed. This problem leads to optimization issue in transport layer. In this paper, we propose a mathematical model which is applied in rate and congestion control in WNMs. From this model, we optimize rate and congestion control in WMNs by maximizing network utility. The proposed algorithm is implemented in distributed way both in links and sources.

A Disembarking Notification Application Based on Smart Device using High Frequencies from Built-in Speaker of Public Transportation

  • Chung, Myoungbeom
    • Journal of the Korea Society of Computer and Information
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    • v.24 no.4
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    • pp.99-105
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    • 2019
  • Recently, many people enjoy movies and music content through their smart devices for using public transportation like as bus or subway. However, because their concentration is aimed at content on their smart devices, passengers sometimes forget to disembark and miss their destination stations. Therefore, in this paper, we propose a destination notification system for disembarking public transport using high frequencies based on the smart devices. We tested 1,000 times real-time destination notification to performance evaluate of the proposed application and service system. According to the test results, the proposed system showed 99.4% and 99.6% accuracy and we confirmed that it could be very useful. As such, the proposed system could be a useful technology for notifying smart device users when to get off public transport, capable of global commercialization.

Streaming Media and Multimedia Conferencing Traffic Analysis Using Payload Examination

  • Kang, Hun-Jeong;Kim, Myung-Sup;Hong, James W.
    • ETRI Journal
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    • v.26 no.3
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    • pp.203-217
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    • 2004
  • This paper presents a method and architecture to analyze streaming media and multimedia conferencing traffic. Our method is based on detecting the transport protocol and port numbers that are dynamically assigned during the setup between communicating parties. We then apply such information to analyze traffic generated by the most popular streaming media and multimedia conferencing applications, namely, Windows Media, Real Networks, QuickTime, SIP and H.323. We also describe a prototype implementation of a traffic monitoring and analysis system that uses our method and architecture.

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A Model Study of Hypoxia in the Rappahannock Estuary, Verginia

  • Park, Kyeong
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 1995.10a
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    • pp.108-109
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    • 1995
  • Hypoxia has persisted during summer in the bottom water of the lower portion of the Rappahannock Estuary, a western shore tributary of Chesapeake Bay. A laterally integrated two-dimensional, real-time model, consisting of linked hydrodynamic and water quality models, was developed to study the contributing processes for hypoxia. The hydrodynamic model gives the information of physical transport processes, both advective and diffusive, to the water quality model, which simulates the spatial and temporal distributions of eight water quality state variables. (omitted)

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Analysis of an SIP System and Implementation of an User Agent Module (SIP 시스템 분석 및 사용자 에이전트 모듈 구현)

  • 이종열;노강래;김준일;신동일;신동규
    • Proceedings of the Korean Information Science Society Conference
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    • 2002.04a
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    • pp.283-285
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    • 2002
  • 본 논문에서는 현재 VOIP(Voice Over IP)기술고서 ITU-T의 H.323에 대응되는 텍스트 기반 프로토콜인 SIP(Session Initiation Protocol)를 구현한 오픈 소스인 VOCAL(Vovida Open Communication Application Library) 시스템의 구조를 분석하고 SIP의 시스템을 구성하는 여러 모듈들을 테스트를 통하여 검증하였다. VOCAL의 사용자 에이전트에 RTP(Real-time Transport Protocol ) 포맷의 데이터를 전송/수신할 수 있는 모듈을 구현하고 검증하여, SIP 시스템에서 사용할 수 있는 사용자 에이전트의 활용에 대한 방안을 제시하였다.

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