• Title/Summary/Keyword: Buffer Control

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A Buffer-constrained Adaptive Quantization Algorithm for Image Compression (버퍼제약에 의한 영상압축 적응양자화 알고리듬)

  • 박대철;정두영
    • Journal of Korea Multimedia Society
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    • v.5 no.3
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    • pp.249-254
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    • 2002
  • We consider a buffer-constrained adaptive quantization algorithm for image compression. Buffer control algorithm was considered with source coding scheme by some researchers and recently a formal description of the algorithm in terms of rate-distortion has been developed. We propose a buffer control algorithm that incorporates the buffer occupancy into the Lagrange multiplier form in a rate-distortion cost measure. Although the proposed algorithm provides the suboptimal performance as opposed to the optimal Vieterbi algorithm, it can be implemented with very low computaional complexity. In addition stability of this buffer control algorithm has been mentioned briefly using Liapnov stability theory.

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Real-time data transmission through congestion control based on optimal AQM in high-speed network environment (고속 네트워크 환경에서 최적AQM기반의 혼잡제어를 통한 실시간 데이터 전송)

  • Hwang, Seong-Kyu
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.25 no.7
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    • pp.923-929
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    • 2021
  • TCP communication and packet communication require transmission control technology to ensure high quality and high reliability. However, in the case of real-time data transmission, an inefficient transmission problem occurs. In order to overcome this problem and transmit the packet reliability, in general, early congestion control using the buffer level as an index was used. Control of the congestion control point and the cancellation point is delayed because the point at which congestion is controlled is based on the buffer level. Therefore, in this paper, not only the buffer level indicator, but also the ideal buffer level, which determines the packet discard probability, is classified so that the transmission rate and buffer level that measure network congestion are close to the level above the optimal setting. As a result, it was shown that the average buffer level can be directly controlled by maintaining the average buffer level by the ideal buffer level set in the experiment to prove the proposed method.

Adaptive rate control scheme for very low bit rate video coding (초고속 전송 매체용 비디오 코딩을 위한 적응적 비트율 제어에 관한 연구)

  • 오황석;이흥규;전준현
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.5
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    • pp.1132-1140
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    • 1996
  • In video coding systems, an effective rate control method is one of the most improtant issues for the good video quality. This paper presents an adaptive rate control scheme based on the buffer fullness, quantization, and buffer utilization for very low bit rate communication lines, such as 16kbit/s, 24bit/s, and so on. The strategy is implemented on H.263, whichis a vide coding algorithm for narrow band telecommunication channels up to 64kbit/s recommended by ITU-T SG15, to show the effectiveness. The simulation result shows that the suggested rate control scheme has better SNR performance and buffer utilization of source coder than those of linear and non-linear[9] buffer control strategies.

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A Frame Skipping Transfer Policy for Server based on Clients Dynamic Buffer Control Signal (클라이언트의 동적 버퍼 제어 신호에 의한 서버의 프레임 생략 전송 정책)

  • Jeong, Hong-Seup;Park, Kyoo-Seok
    • The KIPS Transactions:PartA
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    • v.10A no.6
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    • pp.677-684
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    • 2003
  • Most policies of VOD services are mainly studied about server system, and make no touch on clients buffer stabilization which is the basis of guaranteeing playback quality and playing without cut off. In this paper, we proposed a skipping frame transfer policy that can sending dynamic buffer control signal to server in accordance with clients buffer state of starvation or overrun, and server transfers a skipped frame to client after receive the control signal. And through a simulation, we show the suggested policy is more efficiency on playback quality by buffer stabilization which is by preventing loss and miss for receiving frame due to grow worse client buffer state.

Design of a shared buffer memory switch with a linked-list architecture for ATM applications (Linked-list 구조를 갖는 ATM용 공통 버퍼형 메모리 스위치 설계)

  • 이명희;조경록
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.11
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    • pp.2850-2861
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    • 1996
  • This paper describes the design of AATM switch LIS of shared buffer type with linked-list architecture to control memory access. The proposed switch LSI consists of the buffer memory, controller and FIFO memory blocks and two special circuits to avoid the cell blocking. One of the special circuit is a new address control scheme with linked-list architecture which maintains the address of buffer memory serially ordered from write address to read address. All of the address is linked as chain is operated like a FIFO. The other is slip-flag register it will be hold the address chain when readaddress missed the reading of data. The circuits control the buffer memory efficiently and reduce the cell loss rate. As a result the designed chip operates at 33ns and occupied on 2.7*2.8mm$^{2}$ using 0.8.mu.m CMOS technology.

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On-line Measurement of Buffer Capacity of a Fermentation medium and Estimation of Organic Aicd Production (발효배지의 완충용량의 온라인 측정 및 유기산 생산 추정)

  • Hur, Won;Jung, Yoon-Keun
    • KSBB Journal
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    • v.13 no.4
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    • pp.461-467
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    • 1998
  • A fermentation system was supplemented with a device for the measurement of the durations of alkali pump feeding for automatic pH control and an A/D convertor for precise monitoring of pH value by computer. A software program was developed to measure buffer capacities from the pH signal and the pH control signal during fermentation. By measuring the buffer capacity on-line, levels of acetic acid were estimated by a software sensor using pH signal in a fermentation process of E.coli growing in a minimal medium. The measured values of acetic acid showed correlation to those of estimated by the software sensor. Lacitic acid production was also successfully estimated by the values of buffer capacities measured on-line.

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Design and Analysis of a Transmission Rate Control Algorithm for Client's Buffer on VOD Systems (VOD 시스템에서 클라이언트 버퍼를 위한 전송율 제어 알고리즘의 설계 및 분석)

  • 김완규;박규석
    • Journal of Korea Multimedia Society
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    • v.1 no.1
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    • pp.67-79
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    • 1998
  • In this paper, we present the design and analyze the transmission rate of a control algorithm for the client buffer on the VOD systems. The design is based on the server's data transmission rate and clients' data consumption rate. The proposed algorithm stabilizes the client's buffer by reducing the oscillation phenomena of the buffer. And it uses the BCT (Buffer Check Time) to reduce the scheduling load of the client system. The client's data consumption rate and the buffer size are calculated on the basis of BCT. In case that the predicted buffer size operates in the overrun or starvation the buffer. As the load fluctuation of the network, the transmission rate control policy cannot stabilize the client's buffer alone. The media scaling policy, therefore, also performs its complementary part in stabilizing the client's buffer, and performance evaluation of the proposed algorithm is provided through simulation.

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Advanced Congestion Control Algorithm Using Change of Queue Length in ATM ABR Service (ATM ABR 서비스에서 큐 길이 변화를 이용한 개선된 폭주 제어 알고리즘)

  • 김체훤;강현철;곽지영;남지승
    • Proceedings of the IEEK Conference
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    • 2000.06c
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    • pp.109-112
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    • 2000
  • The EPRCA(Enhanced Proportional Rate Control Algorithm) is one of the explicit rate control algorithm recommended by the ATM forum. EPRCA algorithm is using only two threshold to buffer change is not considered for calculating ER value. In this paper to cover the shortage, two more variables are added for considering increase of buffer quantity. So calculating proper ER would avoid before getting into the congestion situation. To analysis the affect, EPRCA and proposed algorithm are compared through simulation by analysis of change of buffer length and ACR change

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Robustness and resilience of a passive control solution assembling buffer and cladding panels

  • Balzari, Ugo;Balzari, Andrea
    • Smart Structures and Systems
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    • v.20 no.5
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    • pp.637-640
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    • 2017
  • The adoption of cladding panels as dissipation device is a sort of passive control "ante litteram" for residential and commercial buildings. This paper gives details on the current technology outlining the difference between buffer panels and cladding panels. The discussion of robustness and resilience of the resulting system is afforded. It is shown that the strength of such solution, originally related to economy and light weight, is mainly associated with the respect of the main robustness requisites, as well as the short time it requires for removal and replacement (resilience).

Performance analysis of priority control mechanism with cell transfer ratio and discard threshold in ATM switch (ATM 스위치에서 폐기 임계치를 가진 셀전송비율 제어형 우선순위 제어방식의 성능 분석)

  • 박원기;김영선;최형진
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.3
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    • pp.629-642
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    • 1996
  • ATM switch handles the traffic for a wide range of appliations with different QOS(Quality-of-Service) requirements. In ATM switch, the priority control mechanism is needed to improve effectively the required QOS requirements. In this paper, we propose a priority control mechanism using the cell transfer ratio type and discard threshold in order to archive the cell loss probability requirement and the delay requirement of each service class. The service classes of our concern are the service class with high time priority(class 1) and the service class with high loss priority control mechanism, cells for two kind of service classes are stored and processed within one buffer. In case cells are stored in the buffer, cells for class 2 are allocated in the stored and processed within one buffer. In case cells are stored in the buffer, cells for class 2 are allocated in the shole range of the buffer and cells for class 1 are allocated up to discard threshold of the buffer. In case cells in the buffer are transmitted, one cell for class 1 is transmitted whenever the maximum K cells for class 2 are transmitted consecutively. We analyze the time delay and the loss probability for each class of traffic using Markov chain. The results show that the characteristics of the mean cell delay about cells for class 1 becomes better and that of the cell loss probability about cells for class 2 becomes better by selecting properly discard threshold of the buffer and the cell transfer ratio according to the condition of input traffic.

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