• Title/Summary/Keyword: (Transport Network)

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Protocol-independent Information Modeling and Web Services Implementation for Resource Management in NGN Transport Stratum (NGN 전송 층의 자원 관리를 위한 프로토콜 중립적인 정보 모델링과 웹 서비스 구현)

  • Yim, Young-Eun;Kwon, Tae-Hyun;Kim, Choon-Hee;Han, Tae-Man;Jeong, You-Hyeon;Cha, Young-Wook
    • The KIPS Transactions:PartC
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    • v.14C no.5
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    • pp.453-462
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    • 2007
  • NGN is a packet-based converged network to support session and non-session based services in QoS-enabled broadband transport technologies. Resource and admission control functions(RACF) of NGN have been considering COPS and SNMP as resource management protocols to collect network topology and resource status information of transport network. This paper defines requirements of resource management in NGN transport network, and proposes protocol independent information model to keep consistency of data models of each resource management protocol. Based on this information model described with UML class diagram, we designed and implemented NGN resource management system on Web Services.

OTP: An Overlay Transport Protocol for End-to-end Congestion and Flow Control in Overlay Networks

  • Kim, Kyung-Hoe;Kim, Pyoung-Yun;Youm, Sung-Kwan;Seok, Seung-Joon;Kang, Chul-Hee
    • Journal of IKEEE
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    • v.11 no.4
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    • pp.331-339
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    • 2007
  • The problem of architecting a reliable transport system across an overlay network using split TCP connections as the transport primitive is mainly considered. The considered overlay network uses the application-level switch in each intermediate host. We first argue that natural designs based on store-and-forward principles that are maintained by split TCP connections of hop-by-hop approaches. These approaches in overlay networks do not concern end-to-end TCP semantics. Then, a new transport protocol-Overlay Transport Protocol (OTP)-that manages the end-to-end connection and is responsible for the congestion/flow control between source host and destination host is proposed. The proposed network model for the congestion and flow control mechanisms uses a new window size-Ownd-and a new timer in the source host and destination host. We validate our analytical findings and evaluate the performance of our OTP using a prototype implementation via simulation.

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Analytical Solution of Multi-species Transport Equations Coupled with a First-order Reaction Network Under Various Boundary Conditions (다양한 경계조건을 가진 일차 반응 네트워크로 결합된 다종 오염물 거동 해석해)

  • Suk, Hee-Jun;Chae, Byung-Gon
    • Journal of Soil and Groundwater Environment
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    • v.16 no.6
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    • pp.46-57
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    • 2011
  • In this study, analytical solution of multip-species transport equations coupled with a first-order reaction network under constant concentration boundary condition or total flux boundary condition is obtained using similarity transformation approach of Clement et al. (2000). The study shows the schematic process about how multi-species transport equations with first-order sequential reaction network is transformed through the similarity transformation approach into independent and uncoupled single species transport equations with first-order reaction. The analytical solution was verified through the comparison with popular commercial programs such as 2DFATMIC and RT3D. The analytical solution can be utilized in nuclear waste sites where radioactive contaminants and their daughter products occur and in industrial complex cities where chlorinated solvent such as PCE, TCE, and its biodegradation products produces. In addition, it can help the verification of the developed numerical code.

Protocol Behaviors for Multipeer Multimedia Communications

  • Kim, Yong-Woon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 1998.11a
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    • pp.450-455
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    • 1998
  • This paper proposes an enhanced transport protocol for multipeer communications. It is assumed that there exists a transport connection owner that takes the roles of the establishment, management and termination of a transport connection. The proposed protocol classifies the data transfer type into simplex, duplex and N-plex multicasts and provides several transport services to support various requirements in group communications. The general operations and reliability controls of each transfer type are different from one another and carried out by a shared control tree. The QoS negotiation is performed during the creation phase. The notification of negotiated values is followed by an acknowledgment procedure for confirmation. The four-way handshake is introduced. After negotiation, such a resource reservation protocol as RSVP can reserve system and network resources according to the arbitrated values. This paper suggests a conceptual model of the transport layer and its protocol behaviors over the IP multicast and RSVP network.

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A Case Study of a Resource Reservation Protocol in IP Based Wireless Access Networks for ITS Service

  • Jung Kwang Mo;Jung Hyun Chul;Min Sang Won
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.4 no.1 s.6
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    • pp.107-115
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    • 2005
  • For effective IP based service implementation on the wireless network environments, wireless network including the ITS network have to support QoS guaranteed protocol such as a RSVP. RSVP is a resource reservation protocol for Internet environment, and its scalability makes easy to implement RSVP over the various IP transport technologies. But for the If based ITS wireless network environment, RSVP is not suitable, since by its path setup procedure characteristic. In the wireless access network for ITS service, when a mobile node moves to other domain it must perform registration procedure. But the registration procedure is time consuming steps, so if a RSVP session was already established in the previous domain, the RSYP session may be disconnected and the time to re establish a new RSVP session is long enough to cause serious packet loss. In this paper, we propose a pre-path reservation mechanism for applying the RSVP in wireless access networks for ITS. In the pre-path reservation mechanism, the resource reservation procedure occurred during a mobile node's handoff time. An access point in wireless access network performs this procedure when the mobile node attempts handoff The access point executes pre-path reservation procedure as a proxy, since the mobile node does not have IP address until the address allocation procedure is finished in a new domain.

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Efficient Maximal Flow Algorithms in a Large Time-Expanded Network (대규모 시간전개형 네트워크에서의 효율적 최대유량 해법)

  • 이달상
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.19 no.37
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    • pp.211-220
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    • 1996
  • We consider the problem of scheduling a maximal amount of additional, low priority transport through a large multiperiod network, given that we may not interfere with an existing schedule for high priority transport. The problem is transformed into the Time-Expanded network(TENET) without traverse time using TENET Generator (TENETGEN). We describe two specialized heuristic algorithms that guarantee the optimal solutions and show the effectiveness of them by comparing quite favorably with Dinic.

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Subway Network Expansion and Spatial Restructuring of Accessibility in Seoul

  • Lee, Keum-Sook
    • Journal of the Korean Regional Science Association
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    • v.11 no.2
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    • pp.53-63
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    • 1995
  • Changes in transport are reflected in the accessibility of a place, which is denoted as the inherent advantageous characteristics of a place with respect to overcoming spatial friction, and affect the land use ultimately. A composite accessibility measurement scheme is developed and applied to the subway network in Seoul, which has been constructed in 1972. Changes in the transport network are reflected in the spatial structure of accessibility and affect ultimately the land use pattern. Therefore, it is of relevance to examine the changes in the spatial structure of accessibility, which allows to forecast the direction of changes in the land use pattern.

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Analysis of Multiple Network Accessibilities and Commercial Space Use in Metro Station Areas: An Empirical Case Study of Shanghai, China

  • Zhang, Lingzhu;Zhuang, Yu
    • International Journal of High-Rise Buildings
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    • v.8 no.1
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    • pp.49-56
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    • 2019
  • Against the background of the rapid development of the Shanghai Metro network, this paper attempts to establish an analytical approach to evaluate the impact of multiple transport network accessibilities on commercial space use in metro station areas. Ten well-developed metro station areas in central Shanghai are selected as samples. Commercial space floor area and visitors in these areas are collected. Using ArcGIS and Spatial Design Network Analysis, the Shanghai Metro network and road network are modeled to compute diversified transport accessibilities. Evidence from land use and commercial space floor area within a 0-to-500-meter buffer zone of stations is consistent with location and land-use theory: commercial land use is concentrated closer to stations. Correlation analysis suggests that hourly visitors to the shopping mall are mainly influenced by metro network accessibility, while retail stores and restaurants are affected by both metro and pedestrian accessibility.

Network-adaptive Transport Scheme for Transparency of Force-reflecting Teleoperation (힘 반향 원격제어 시스템의 투명성을 위한 네트워크 적응형 전송 기법)

  • Lee, Seok-Hee;Seo, Chang-Hoon;Ryu, Je-Ha;Kim, Jong-Won
    • 한국HCI학회:학술대회논문집
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    • 2009.02a
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    • pp.45-51
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    • 2009
  • In this paper, a transparency analysis and network-adaptive transport scheme are proposed in order to improve transparency of EBA-based force-reflecting teleoperation. EBA guarantees stability of force-reflecting teleoperation over network delay and loss but has limitation that it cannot overcome transparency deterioration of haptic interactions. The proposed transparency analysis quantifies the force feedback distortion caused by network delay and loss. Based on the analysis, the proposed haptic data synchronization and transmission rate control schemes adapt synchronization delay and transmission rate to current network state for more transparent haptic interaction. Through Matlab/Simulink simulations, it is confirmed that the proposed analysis provides an acceptable quantification method about haptic interaction quality and that the proposed haptic data transport scheme effectively improves haptic interaction quality with respect to network delays and losses.

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Modeling and Trends of Road Transport Development in Eastern European Countries

  • Viktoriia Harkava;Olena Pylypenko;Oleksandr Haisha;Armen Aramyan;Volodymyr Kairov
    • International Journal of Computer Science & Network Security
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    • v.24 no.3
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    • pp.189-195
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    • 2024
  • Road transport occupies the largest share in domestic and international transport. It is of key importance for the development of the economy, forasmuch as it provides the livelihood of the population, the development of the national economy, the possibility of establishing foreign economic relations. The purpose of the research is as follows: analysis of the current state of functioning of the road transport sector in Eastern Europe and identification of key problems and trends in its development. Research methods: Methods of grouping, comparison and generalization, correlation analisys have been used to identify the dynamics of the main indicators of road transport in Eastern Europe. The method of correlation-regression analysis has been applied to determine the impact of increasing the length of roads on the turnover of the road freight transport and the number of employed population in this area. Results. It has been found that the increase in the employed population by 96% and increase in revenues from transportation and storage of goods, postal and courier services (turnover of the road freight transport - in the original language) in the field of road transport by 82% is explained by the change in transport infrastructure capacity by increasing length of highways. According to the correlation analysis, it has been revealed that there is a high direct dependence between the length of roads and increased revenues from transportation and storage of goods in the field of road transport, as well as between the length of roads and increasing employment in this area.