• Title, Summary, Keyword: leaky

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THE DISCRETE-TIME ANALYSIS OF THE LEAKY BUCKET SCHEME WITH DYNAMIC LEAKY RATE CONTROL

  • Choi, Bong-Dae;Choi, Doo-Il
    • Communications of the Korean Mathematical Society
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    • v.13 no.3
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    • pp.603-627
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    • 1998
  • The leaky bucket scheme is a promising method that regulates input traffics for preventive congestion control. In the ATM network, the input traffics are bursty and transmitted at high-speed. In order to get the low loss probability for bursty input traffics, it is known that the leaky bucket scheme with static leaky rate requires larger data buffer and token pool size. This causes the increase of the mean waiting time for an input traffic to pass the policing function, which would be inappropriate for real time traffics such as voice and video. We present the leaky bucket scheme with dynamic leaky rate in which the token generation period changes according to buffer occupancy. In the leaky bucket scheme with dynamic leaky rate, the cell loss probability and the mean waiting time are reduced in comparison with the leaky bucket scheme with static leaky rate. We analyze the performance of the proposed leaky bucket scheme in discrete-time case by assuming arrival process to be Markov-modulated Bernoulli process (MMBP).

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Adaptive Leaky Factor Determination for Robust Video Transmission over Error-Prone Networks

  • Kim, Jun-Hyung;Hwang, Min-Cheol;Wang, Tae-Shick;Nam, Ju-Hun;Ko, Sung-Jea
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • pp.263-266
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    • 2009
  • When video packets are transmitted over error-prone networks, the leaky prediction can be used to mitigate the effect of error propagation. The leaky factor provides trade-off between coding efficiency and error resilience in the leaky prediction. In this paper, we propose an improved leaky prediction method where the leaky factor is adaptively determined for each frame by minimizing the estimated end-to-end distortion at the encoder. Experimental results show that the proposed method with the adaptive leaky factor shows the better performance of the error robustness as compared with the conventional method.

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Worst Average Queueing Delay of Multiple Leaky-Bucket-Regulated Streams and Jumping-Window Regulated Stream

  • Lee, Daniel C.
    • Journal of Communications and Networks
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    • v.6 no.1
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    • pp.78-87
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    • 2004
  • This paper presents deterministic, worst-case analysis of a queueing system whose multiple homogeneous input streams are regulated by the associated leaky buckets and the queueing system that has a single stream regulated by the jumping-window. Queueing delay averaged over all items is used for performance measure, and the worst-case input traffic and the worst-case performance are identified for both queueing systems. For the former queueing system, the analysis explores different phase relations among leaky-bucket token generations. This paper observes how the phase differences among the leaky buckets affect the worst-case queueing performance. Then, this paper relates the worst-case performance of the former queueing system with that of the latter (the single stream case, as in the aggregate streams from many users, whose item arrivals are regulated by one jumping-window). It is shown that the worst-case performance of the latter is identical to that of the former in which all leaky buckets have the same phase and have particular leaky bucket parameters.

A Performance Study on Congestion Control Schemes for the Broadband Communication Networks (광대역통신망에서 폭주제어 방식에 대한 성능연구)

  • Doo-yeong Park
    • The Journal of Engineering Research
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    • v.6 no.2
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    • pp.39-46
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    • 2004
  • In this paper, we carry out a performance study related to the Broadband Network. For this network, it has been proposed to use the leaky bucket as a way of controlling congestion within the network. On the top of leaky bucket type rate based congestion control scheme for high speed networks, a user will typically operate an error control scheme for retransmitting lost and erroneous packets. We propose a performance model in order to study the interaction between a user's error control scheme and the leaky bucket congestion control scheme for high speed networks. Simulation results show that parameters such as the window size and the token generation rate in the leaky bucket are key factors affecting the end-to-end delay.

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Leaky Dispersion Characteristics in Circular Dielectric Rod Using Davidenko's Method

  • Kim Ki Young;Tae Heung-Sik;Lee Jeong-Hae
    • Journal of electromagnetic engineering and science
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    • v.5 no.2
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    • pp.72-79
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    • 2005
  • The leaky dispersion characteristics of a circular dielectric rod were investigated using Davidenko's method for several lower-order transverse magnetic(TM) modes. The normalized complex propagation constants were precisely determined and their tolerances below $10^{-10}$ compared with zero for both real and imaginary parts. It was also checked whether the normalized complex propagation constants obtained represented forward leaky waves. The leaky modes existing below the cutoff frequency of the guided mode were classified as a nonphysical mode, reactive mode, antenna mode, and spectral gap based on a precise determination of the complex propagation constants. Finally, the effects of the dielectric constant and radius of the dielectric rod on the leaky dispersion characteristics were also considered.

Study on the Relationship between Dae-Jang-Jung-Gyeok(大腸正格) and Leaky Gut Syndrome (대장정격증(大腸正格證)과 장누수증후군(Leaky Gut Syndrome)과의 관계 고찰(考察))

  • Lee, Jin-Cheoul;Park, Sang-Kyun;Bang, Jung-Kyun
    • Journal of Korean Medical classics
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    • v.26 no.4
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    • pp.105-116
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    • 2013
  • Objective : If the penetration ratio of the intestinal mucosa is increased, the toxic or unhealthy materials - which should not be absorbed into our bodies - will be come into our bodies. They cause a sort of anti-toxic response or confusion of the immune system, and ultimately bring various types of diseases. This syndrome is related "Poison in Excrement" or "Internal Damage(內傷發癍)" and Leaky Gut Syndrome, so I will study on the relationship between them. Method : Study on the relationship between Dae-Jang-Jung-gyeok and Leaky Gut Syndrome. Result : Korean doctors in ancient times called this syndrome "Poison in Excrement" or "Internal Damage(內傷發癍)" and treated it with "Dae-Jang-Jung-Gyeok(大腸正格)". Leaky Gut Syndrome is a sort of clinical lesion, which allows foreign and harmful toxins in and results in a disorder of the immune system due to the leaking intestinal mucosa. Conclusion : Based upon the analyses, Dae-Jang-Jung-Gyeok and Leaky Gut Syndrome are closely related. Therefore diseases caused by the Leaky Gut Syndrome might be expected to be cured by Dae-Jang-Jung-Gyeok. Particularly the use of treatments for self-immune diseases and allergic diseases such as atopyic dermatitis and articular rheumatism should be expected to reveal a new path of treatment for other disorders such as Leaky Gut Syndrome.

A study on improvement of leaky bucket UPC algorithm in ATM networks (ATM 망에서의 Leaky Bucket UPC 알고리즘의 성능 개선에 관한 연구)

  • 심영진;박성곤;조용환
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.5
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    • pp.1116-1125
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    • 1997
  • In this paper, the modified UPC(Usage Parameter Control) algorithm is proposed. The proposed UPC algorithm is based on Leakey Bucket algorithm and adds the characteristics of the jumping window algorithm for monitoring the average bit rate. The proposed algorithm let a cell, which is tagged by Leaky Bucket algorithm, pass through the network, if the network does not violate the average bit rate. The measuring method of window mechanism like jumping window. This paper supposes On/Off traffic source model of rthe performance evaluation and analysis of the proposed algorithm. Therefore, as simulation results, the proposed algorithm acquires more reduced results of the cell loss rate and bucket size than the Leaky Bucket algorithm.

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The Improved Dual Leaky Bucket Algorithm for Multimedia Synchronization (미디어동기화를 위한 개선된 Dual Leaky Bucket 알고리즘)

  • 최용길;이기영
    • Proceedings of the IEEK Conference
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    • pp.50-53
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    • 1998
  • In this paper, the modified Usage Parameter Control(UPC) method based on Dual Leaky Bucket algorithm is proposed to improve the perfor mance of multimedia synchronization and to control burst traffic. In the proposed algorithm, Synchronous cells are by passed to the 2nd stage Leaky Bucket (LB) of the DLB. for overloaded traffic condition, the violated cells are saved in a temporary buffer and they are retransmitted when the 2nd stage bucket is empty.

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A Queueing Model for Traffic Control in Leaky Bucket System (Leaky Bucket 시스템에서 트래픽제어에 관한 대기행렬모형)

  • 횡철희;이호우;윤승현;안부용;박노익
    • Journal of the Korean Operations Research and Management Science Society
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    • v.22 no.2
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    • pp.45-65
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    • 1997
  • We build a queueing model for buffered leaky bucket system. First, we set up system equations and them calculate the steady-state probabilities at an arbitrary time epoch by recursive method. We derive the mean waiting time and the mean number of cells in the input buffer, and evaluate the performance of the buffered leaky bucket system to find the optimal queue capacity and token generation rate that meet the quality of service(QoS).

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The Effect on the Quality of Service in ATM Network of Leaky Bucket Algorithm (ATM망의 서비스 품질에 Leaky Bucket 알고리즘이 미치는 영향)

  • 소경영;김영수
    • Journal of the Korea Society of Computer and Information
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    • v.3 no.1
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    • pp.125-148
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    • 1998
  • The use of shaping mechanism, realized by means of a leaky bucket based algorithm on input traffic of an ATM network allows to achieve higher utilization of network resources, and to guarantee the quality of service requested by the users. The functionalities of the shaping mechanism based on leaky bucket, are characterized by the token pool sire and by input queue size. In this paper we have analyzed, using simulations, the effect on the quality of service in ATM network of leaky bucket algorithm when shaper parameters described above are changed.

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