• Title/Summary/Keyword: switch cell

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Mathematical Analysis of the Parallel Packet Switch with a Sliding Window Scheme

  • Liu, Chia-Lung;Wu, Chin-Chi;Lin, Woei
    • Journal of Communications and Networks
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    • v.9 no.3
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    • pp.330-341
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    • 2007
  • This work analyzes the performance of the parallel packet switch (PPS) with a sliding window (SW) method. The PPS involves numerous packet switches that operate independently and in parallel. The conventional PPS dispatch algorithm adopts a round robin (RR) method. The class of PPS is characterized by deployment of parallel low-speed switches whose all memory buffers run more slowly than the external line rate. In this work, a novel SW packet switching method for PPS, called SW-PPS, is proposed. The SW-PPS employs memory space more effectively than the existing PPS using RR algorithm. Under identical Bernoulli and bursty data traffic, the SW-PPS provided significantly improved performance when compared to PPS with RR method. Moreover, this investigation presents a novel mathematical analytical model to evaluate the performance of the PPS using RR and SW method. Under various operating conditions, our proposed model and analysis successfully exhibit these performance characteristics including throughput, cell delay, and cell drop rate.

Single Buffer types of ATM Switches based on Circulated Priority Algorithm (순환적 순위 알고리즘을 이용한 단일형 버퍼형태의 ATM스위치)

  • Park Byoung-soo;Cho Tae-kyung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.5 no.5
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    • pp.429-432
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    • 2004
  • In this paper, we propose a new sorting algorithm for ATM switch with a shared buffer which has a sequencer architecture with single queue. The proposed switch performs a sorting procedure of ATM cell based on the output port number of ATM cell with hardware implementation. The proposed architecture has a single buffer physically but logically it has function of multi-queue which is designed at most to control the conflicts in output port. In the future, this architecture will take various applications for routing switch and has flexibility for the extension of system structure. therefore, this structure is expected on good structure in effective transmission.

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Time-division hybrid WDM photonic switch architecture (시분할 하이브리드 WDM 광스위치 구조)

  • 김기태;엄진섭;김우찬;신서용;정홍식
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.34D no.5
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    • pp.52-60
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    • 1997
  • Photonic switching systems with throughput above Tbit/s are reuried to transport vast amounts of information for the coming B-ISDN. In this paper, we proposed a new time-division hybrid WDM photonic swithc architecture, the proposed basic switch module has simple configuratin consisted of frequency routers for wavelength division and cell coders and star couplers for time division. Through the comparison with other sysems in field of switching capacity, hardware complexity and cost effect of implemetnation, we proved that the proposed system is suitable for large-capacity photonic switching system.

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A New Criterion of Cell Discard in an ATM Switch with Input and Output Buffers (입출력버퍼형 ATM 교환기의 셀 폐기 방법에 대한 새로운 기준 제안 및 성능 분석)

  • Gwon, Se-Dong;Park, Hyeon-Min;Choe, Byeong-Seok;Park, Jae-Hyeon
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.4
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    • pp.1246-1264
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    • 2000
  • An input-output buffering switch operates in either of tow different cell loss modes; Backpressure mode and Queueloss mode. In the previous studies, the Backpressrue mode is more effective at low traffic loads, and the Queueloss mode performs better at high traffic. We propose a new operation mode, called Hybrid mode, which adopts the advantages of he Backpressure and the Queueloss mode. Backpressure and Queueloss modes are distinguished from whether a cell loss occurs at the output buffer or not when output buffer overflows, irrespective of input buffer status. In order to simply combine Backpressure and Queueloss mode, the change of input traffic load must be measured. However, in the Hybrid mode, simply both of the input and output buffer overflow and checked out to determine the cell discard. The performance of the Hybrid mode is compared with those of the Backpressure and the Queueloss mode under random and bursty traffic. This paper show that the Hybrid mode always gives the best performance results for most ranges of load values.

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Power Cell-based Pulsed Power Modulator with Fast Rise Times (빠른 상승 시간을 갖는 파워 셀 기반 펄스 파워 모듈레이터)

  • Lee, Seung-Hee;Song, Seung-Ho;Ryoo, Hong-Je
    • The Transactions of the Korean Institute of Power Electronics
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    • v.26 no.1
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    • pp.25-31
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    • 2021
  • This paper describes the design of a power cell-based pulsed power modulator with fast rise times. The pulse-generating section of the pulse power modulator is a series stack of power cells. Each power cell is composed of a storage capacitor, a pulse switch, and a bypass diode. When the pulse switches are turned on, the capacitors are connected in series and the sum of voltages is applied to the load. For output pulses with fast rise times, an IGBT with fast turn-on characteristics is adopted as a pulse switch and the optimized gate driving method is used. Pspice simulation is performed to account for the gate driving method. A 10 kV, 12-power cell-based pulsed power modulator is tested under resistive load and plasma reactor load. The rise times of output pulses less than 20 ns are confirmed, showing that the pulsed power modulator can be effectively applied to pulsed power applications with fast rise times.

Battery Balancing Method using 2-Switch Flyback Converter (2-스위치 플라이백 컨버터를 이용한 배터리 밸런싱 기법)

  • Kim, Woo-Joon;Kim, Ui-Jin;Park, Seong-Mi;Park, Sung-Jun;Son, Gyung-Jong
    • Journal of the Korean Society of Industry Convergence
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    • v.25 no.3
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    • pp.451-459
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    • 2022
  • Recently, in accordance with the demand for a large capacity of a secondary battery according to an increase in the demand for energy storage devices, a modular series battery configuration is essential. Accordingly, various cell balancing techniques have been proposed to prevent high efficiency and performance degradation of the battery. In this paper, propose a battery voltage balancing topology consisting of a flyback DC/DC converter type of a SIMO (Single-Input-Multiple Output) two-switch configuration for a series battery configuration. The proposed topology shows a structure in which a DC/DC converter connected to each module and a battery cell share one transformer. The topology cell balancing operation is a principle in which the voltage balancing converter of the battery converges to the same value through a transformer that shares a magnetic flux with the cells constituting the module through a single high-frequency transformer. In this paper, the dynamic characteristics analysis of the proposed circuit using PSIM was based and it was verified through experiments on one module.

Call Admission Control for Shared Buffer Memory Switch Network with Self-Similar Traffic (Self-Similar 트래픽을 갖는 공유버퍼 메모리 스위치 네트워크 환경에서 호 수락 제어 방법)

  • Kim Ki wan;Kim Doo yong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.4B
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    • pp.162-169
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    • 2005
  • Network traffic measurements show that the data traffic on packet switched networks has the self-similar features which is different from the traditional traffic models such as Poisson distribution or Markovian process model. Most of the call admission control researches have been done on the performance analysis of a single network switch. It is necessary to consider the performance analysis of the proposed admission control scheme under interconnected switch environment because the data traffic transmits through switches in networks. From the simulation results, it is shown that the call admission control scheme may not operate properly on the interconnected switch even though the scheme works well on a single switch. In this parer, we analyze the cell loss probability, utilization and self-similarity of output ports of the interconnected networks switch by using shared buffer memory management schemes and propose the new call admission control scheme considering the interconnected network switches under self-similar traffic environments.

A Performance Analysis and Evaluation of Congestion Avoidance Algorithm for ABR service over ATM Networks (ATM망에서 ABR 서비스를 위한 혼잡회피 알고리즘의 성능 분석 및 평가)

  • 하창승;조익성
    • Journal of the Korea Society of Computer and Information
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    • v.7 no.3
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    • pp.80-91
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    • 2002
  • A general goal of the AT%(Asynchronous Transfer Mode) network is to support connect across various network. On ATM networks, ABR services are provided using the remained ban after allocation CBR and VBR traffic. Realtime services such as transmitting audio or video data may be provided using CBR ado VBR which have a constrained transmission delay, but in these cases, the communications bandwidth may be wasted. In this paper a simulation has been performed to compare and evaluate the performance between the ERICA(Explicit Rate Indicate Avoidance) and EPRCA(Enhanced Proportional Rate Control Algorithm) switches which use Explicit Rate switch algorithm for ABR switch. The variation of the ACR at the source end system, the queue length, the utilization rate of the link bandwidth and the share fairness at the transient and steady states are used as the evaluation criteria for the simulation. As a result of simulation, ERICA algorithm switch was ten times long compared to ERPCA switch to achieve assigned fair share. so EPRCA switch is superior to ERICA about load response. For Fair share and stability, ERICA switch is excellent to EPRCA switch.

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Tumor therapy with Amanita phalloides (Death Cap): stabilization of mammary duct cancer

  • Riede, Isolde
    • CELLMED
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    • v.1 no.1
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    • pp.5.1-5.3
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    • 2011
  • Molecular events that cause tumor formation enhance a number of HOX genes, called switch genes, coding for RNApolymeraseII transcription factors. Thus, in tumor cells, RNApolymeraseII is more active than in other somatic cells. Amanita phalloides contains amanitin which inhibits RNApolymeraseII. Partial inhibition with amanitin influences tumor cell - but not normal cell - activity. To widen the treatment spectrum, dilutions of Amanita phalloides, containing amanitin, are applied to a patient with mammary duct cancer. For monitoring tumormarkers, different doses of amanitin are applied. The former duplication time of tumor growth represented three months; however within a period of 18 months the patient can be stabilized without further growth of the tumor. There are also no severe symptoms, no liver damage and no continuous erythrocyte deprivation. This new principle of tumor therapy shows high potential to provide a medical treatment.

The Analysis of Color Vision Defects Mechanism for the Electric Circuits (전기적 회로에 의한 색각이상 mechanism 해석)

  • Park, Sang-An;Kim, Yong-Geun
    • Journal of Korean Ophthalmic Optics Society
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    • v.6 no.1
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    • pp.81-85
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    • 2001
  • The color vision was composed of the wavelength absorption of three R. G. B cone photo-receptors and the r-g, y-b channel of an opponent process. The color vision defects mechanism for the electric circuit made up a photo cell, relay switch and transformer. This mechanism very well applied to the color vision defects mechanism owing to be y-b chromatic valence function in case of a cone R or G defects and to be r-g chromatic valence function in case of a cone B defects.

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