• Title/Summary/Keyword: 혼잡도

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A Multiple User Class Congestion Pricing Model and Equity (혼잡통행료 산정모형의 개발 및 계층간 형평성 연구)

  • Im, Yong-Taek;Kim, Byeong-Gwan
    • Journal of Korean Society of Transportation
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    • v.25 no.5
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    • pp.183-193
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    • 2007
  • Traditionally, a congestion charge based on first-best congestion pricing theory, namely, the theory of marginal cost pricing theory, is equal to the difference between marginal social cost and marginal private cost. It is charged on each link so as to derive a user equilibrium flow pattern to a system optimal one. Based on this theory this paper investigates on the characteristics of first-best congestion pricing of multiple user class on road with variable demand, and presents two methods for analysis of social and spatial equity. For these purposes, we study on the characteristics of first-best congestion pricing derived from system optimal in time and in monetary unit, and analyze equity from this congestion pricing with an example network.

Adaptive Congestion Control for Effective Data Transmission in Wireless Sensor Networks (센서네트워크에서의 효율적인 데이터 전송을 위한 적응적 혼잡 제어)

  • Lee, Joa-Hyoung;Gim, Dong-Gug;Jung, In-Bum
    • The KIPS Transactions:PartC
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    • v.16C no.2
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    • pp.237-244
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    • 2009
  • The congestion in wireless sensor network increases the ratio of data loss and causes the delay of data. The existing congestion protocols for wireless sensor network reduces the amount of transmission by control the sampling frequency of the sensor nodes related to the congestion when the congestion has occurred and was detected. However, the control method of sampling frequency is not applicable on the situation which is sensitive to the temporal data loss. In the paper, we propose a new congestion control, ACT - Adaptive Congestion conTrol. The ACT monitors the network traffic with the queue usage and detects the congestion based on the multi level threshold of queue usage. Given network congestion, the ACT increases the efficiency of network by adaptive flow control method which adjusts the frequency of packet transmission and guarantees the fairness of packet transmission between nodes. Furthermore, ACT increases the quality of data by using the variable compression method. Through experiment, we show that ACT increases the network efficiency and guarantees the fairness to sensor nodes compared with existing method.

Design of Congestion Standardization System Based on IoT (IoT를 접목한 지하철 객차 내 혼잡도 평준화 시스템 설계)

  • Kim, Mi-Rye;Cho, In-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.5
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    • pp.74-79
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    • 2016
  • The Seoul Metropolitan Subway, which started operating in 1974, plays a major role in transporting 7,289 thousands passengers daily. This trend of a steadily increase in passengers from 2012 has increased the congestion rate because of the limited capacity and time. To solve this problem, Seoul city is consistently working on improving the subway facilities, such as the construction of a detour path. This project, however, has only a slight effect on improving the congestion rate and is too expensive to construct the facilities. Hence, this study suggests The Congestion Standardization System based on the IoT for improving the subway congestion rate. Based on the system, the expected effect analysis was performed, which resulted in a decrease in ride passengers from 34 to 20. In addition, this expected effect analysis shows that the number of subway vehicles can increase from 20 to 24. The suggested system will have a significant effect on the efficiency of the management system.

Effects of Store Crowding on Store Attitude and Behavioral Intention - Based on adjustment effects of consumer susceptibility (점포 혼잡성이 점포태도와 행동의도에 미치는 영향 - 소비자 동조성의 조절효과를 중심으로)

  • Choo, Mi-Ae
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.4
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    • pp.965-972
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    • 2014
  • Attitudes and behavior within the store congestion of the store is a store in any manner affect the formation process of investigating synchronism in the control of the consumer appears to analyze the influence of enemy has its purpose. Store and spatial congestion factor of social behavioral factors also revisit the help of word-of-mouth is. Consumer groups with high and low groups of synchronism suggested. Social attitudes towards the store congestion significantly positive effect that I've shown, it was not significant spatial congestion. During a revisit of action is a statistically significant relationship that I've shown, is a significant effect of word-of-mouth relationship was not significant. Investigating the moderating effects of consumer synchronism result of high consumer groups a significant impact on the social congestion showed, at low spatial influence congestion.

Congestion Control Method of Area of Interest in Distributed Virtual Environment (분산가상환경에서 참여자 관심영역의 혼잡도 조절기법)

  • 유석종
    • Journal of Korea Multimedia Society
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    • v.7 no.4
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    • pp.550-558
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    • 2004
  • Previous researches on scalability problem of distributed virtual environment (DVE) have been mainly focused on spatial partitioning of area of interest (AOI). Congestion phenomena by avatar groups in AOI have been neglected relatively However, AOI congestion is highly related to scalability of DVE because it exhausts system resources such as network bandwidth and rendering time, and could be a bar to perform collaboration among participants. In this paper, this will be defined as the problem that must be solved for the realization of the scalable DVE, and a model will be proposed to measure and control congestion situation in AOI. The purposes of the proposed model are to prevent high density of participants in AOI, and to protect stable collaboration in DVE. For evaluation of the performance it is compared with a previous method by defining the resource cost model which is dynamically activated to AOI congestion.

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A Study on the Feasibility of the Improvement of Traffic Congestion : Focusing on Small and Medium-Sized Cities in Chuncheong Province (중소도시 교통혼잡도로 적용범위에 관한 연구 : 충청권 중심으로)

  • Kwon, Hyun Joong;Oh, Ju Taek
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.18 no.3
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    • pp.34-45
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    • 2019
  • Based on the analysis of congestion conditions in small cities with a population of less than 500,000 in Chungcheong Province, this study conducted a feasibility study on the scope of congestion improvement projects. Further, traffic congestion management standards were further established by analyzing LOS as well as the speed of traffic presented by congestion criteria in the existing Project. According to the analysis according to the congestion management standard LOS suggested in this study, Asan city has the most major number of highways where LOS E occurs for more than 3 hours, followed by Sejong City and Gongju City. In addition, when comparing the ratio of the busy main roads according to the frequency of LOS E by city size, it was analyzed that the ratio and extension of the busy highways relative to the overall extension of the large Chungcheong area are similar to the ratio in small cities in the Chungcheong region. Therefore, traffic congestion occurred in small cities and the feasibility of the improvement project was revealed.

A Congestion Control Technique for the Bottleneck Nodes in Wireless Sensor Networks (싱크 주변 노드를 위한 센서 네트워크 혼잡 제어 기술)

  • Moon Sung-Hyun;Lee Sung-Min;Cha Ho-Jung
    • Proceedings of the Korean Information Science Society Conference
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    • 2006.06d
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    • pp.154-156
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    • 2006
  • 본 논문은 기존의 혼잡 제어 기술이 전체 노드들을 위해 설계 되어 싱크 주변에서 생성되는 특별한 혼잡을 해결 할 수가 없기 때문에 싱크 주변 노드를 위한 혼잡 제어 기술을 제안한다. 싱크 주변에서 일어나는 'Bottle Neck' 문제가 일어났을 경우 데이터의 분석에 의한 우선순위결정과 타임 스케줄을 이용한 순차적인 데이터 전송으로 혼잡을 줄이고 그로 인해 데이터의 의미 있는 전송과 신뢰성을 동시에 만족시킨다. 또한 이 기술은 멀티 싱크 또는 모바일 싱크에도 적용 시킬 수 있고, 기존의 전체 노드를 위한 혼잡 제어 기술과 제시하는 기술을 혼용하여 사용할 수도 있다. 본 논문이 제안하는 기법은 혼잡 제어를 하지 않은 상태에서의 데이터 전달 방식에 비해 데드라인 만료 비율이 1.5%이상 감소하였고 프레임 손실율 또한 28%이상 감소하였다.

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Optimal Transmission Rate Allocation Algorithm in ABR Service of ATM Network (ATM 망의 ABR 서비스에서 최적 대역할당 기법에 대한 연구)

  • 김용진;김중규
    • Proceedings of the Korea Society for Industrial Systems Conference
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    • 1999.12a
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    • pp.103-111
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    • 1999
  • ATM 망의 혼잡상태를 회피하기 위하여 다양한 방법들이 제안되고 있으며, 이들 중에는 전송시스템에 존재하는 스위치의 버퍼 값에 지능형 마킹을 표시함으로서 각 전송회선에 공평한 대역폭을 할당하며 혼잡상태를 회피하는 방법이 있다 ATM Forum은 ATM 망에서 ABR 서비스의 혼잡제어를 위한 표준으로서 셀률 기반 혼잡제어기법을 적용하고 있다. EPRCA(Enhanced Proprotional Rate Control Algorithm)은 망의 상태를 항상 검사하는 것이 아니라 망의 혼잡이 발생하였을 때만 작동하기 때문에 부정확한 셀률 정보를 가질 수 있다. DMRCA(Dynamic Max Rate Control Algorithm)은 혼잡의 정도에 따라서 적절한 셀률을 부여하기 위하여 스위치에 임계값을 지정하며, 셀률은 스위치에서 제공되는 증가계수와 감소계수에 비례하여 변하게 된다. 본 논문은 DMRCA에서 혼잡제어를 위해서 적용하는 증가/감소변수의 크기 변화에 따른 공평대역할당의 수렴속도를 평가하여 최적의 변수값을 찾고자 한다.

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Study of Congestion Control Mechanism for Heterogeneous Sensor Networks (이종 센서 네트워크의 혼잡 제어 메커니즘 연구)

  • Choi, Dongmin;Baek, Cheolheon;Chung, Ilyong
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2015.07a
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    • pp.277-278
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    • 2015
  • 본 연구는 기존에 제안되었던 혼잡 제어 기법, 그리고 여기에서 고려하지 못한 다종 센서 네트워크 환경을 고려한 혼잡 제어 기법에 대한 연구를 포함한다. 기존의 방법은 대규모 센서 네트워크 또는 특정한 타입의 데이터를 가정하고 혼잡 제어 기법을 제안하였다. 그러나 최근의 센서 네트워크 응용은 다양한 센서의 개발로 그 범위가 확장되는 추세에 있어 다수의 이종 센서 노드가 네트워크 구성 인자로 참여하는 환경이므로 이에 대한 연구가 필요하다. 이에 우리는 기존의 혼잡 제어 메커니즘은 분석하고 이종 센서가 참여하는 센서 네트워크를 고려하는 혼잡 제어 기법을 연구한다.

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Improving the Fairness of TFRC Congestion Control Protocol (TFRC 혼잡제어 프로토콜 공정성 개선 방안)

  • 조경연;김영복;장주욱
    • Proceedings of the Korean Information Science Society Conference
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    • 2002.10e
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    • pp.406-408
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    • 2002
  • TFRC 혼잡제어는 멀티미디어, 인터넷 전화등 실시간성이 강조된 서비스에 적합한 프로토콜이다. 그러나 이러한 TCP-friendly 혼잡제어 알고리즘은 네트워크 혼잡이 심해져 손실률이 커짐에 따라 TCP와의 공정성(fairness)이 떨어지는 문제점을 가지고 있다. 이러한 문제를 해결하기 위해서는 전송률을 결정하는 제어식을 높은 손실률일 때 보정을 해주어야 한다. 본 논문에서는 TFRC 혼잡제어 알고리즘의 전송률 결정에 있어서 중요한 변수인 재전송 타임아웃 값(RTO)의 재 정의를 통하여 전송률을 보정함으로서 공정성 하락을 방지함을 보이고, 시뮬레이션을 통하여 이를 입증한다.

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