• Title/Summary/Keyword: burst

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Modeling and Analysis of Burst Switching for Wireless Packet Data (무선 패킷 데이터를 위한 Burst switching의 모델링 및 분석)

  • Park, Kyoung-In;Lee, Chae Young
    • Journal of Korean Institute of Industrial Engineers
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    • v.28 no.2
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    • pp.139-146
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    • 2002
  • The third generation mobile communication needs to provide multimedia service with increased data rates. Thus an efficient allocation of radio and network resources is very important. This paper models the 'burst switching' as an efficient radio resource allocation scheme and the performance is compared to the circuit and packet switching. In burst switching, radio resource is allocated to a call for the duration of data bursts rather than an entire session or a single packet as in the case of circuit and packet switching. After a stream of data burst, if a packet does not arrive during timer2 value ($\tau_{2}$), the channel of physical layer is released and the call stays in suspended state. Again if a packet does not arrive for timerl value ($\tau_{1}$) in the suspended state, the upper layer is also released. Thus the two timer values to minimize the sum of access delay and queuing delay need to be determined. In this paper, we focus on the decision of $\tau_{2}$ which minimizes the access and queueing delay with the assumption that traffic arrivals follow Poison process. The simulation, however, is performed with Pareto distribution which well describes the bursty traffic. The computational results show that the delay and the packet loss probability by the burst switching is dramatically reduced compared to the packet switching.

The Evaluation of Burst Pressure for Corroded Pipeline by Full Scale Burst Test (실배관 파열시험을 통한 부식배관의 파열압력 평가)

  • Kim, Yeong-Pyo;Baek, Jong-Hyeon;Kim, U-Sik;Go, Yeong-Tae
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.1
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    • pp.203-210
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    • 2002
  • The transmission pipeline industry spends many millions of dollars annually performing inline inspections, excavating sites of possible corrosion, and repairing or replacing damaged sections of pipe. New criteria fur evaluation of the integrity of corroded pipe have been developed in recent years to help in controlling these costs. These new criteria vary widely in their estimates of integrity and the most appropriate criterion fur a given pipeline is net always clear. This paper presents an overview, comparison and evaluation of acceptability criteria for corrosion deflects in pipelines. By full scale burst tests, this paper has assessed the relative accuracy of each of theses criteria in predicting burst pressure. Many of the criteria appear to be excessively conservative and indicate that deflects must be repaired when none is needed, based upon burst test data.

The Evaluation of Burst Pressure for Corroded Weld in Gas Pipeline (가스배관 용접부위 부식에 대한 파열압력 평가)

  • Kim, Young-Pyo;Kim, Woo-Sik;Lee, Young-Kwang;Oh, Kyu-Hwan
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.222-227
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    • 2004
  • The failure assessment for corroded pipeline has been considered with the full scale burst test and the finite element analysis. The burst tests were conducted on 762 mm diameter, 17.5 mm wall thickness and API 5L X65 pipe that contained specially manufactured rectangular corrosion defect. The failure pressure for corroded pipeline was measured by burst testing and classified with respect to corrosion sizes and corroded regions - the body, the girth weld and the seam weld of pipe. Finite element analysis was carried out to derive failure criteria of corrosion defect on the pipe. A series of finite element analyses were performed to obtain a limit load solution for corrosion defects on the basis of burst test. As a result, the criteria for failure assessment of corrosion defect within the body, the girth weld and the seam weld of API 5L X65 gas pipeline were proposed.

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Efficient Channel Scheduling Technique Using Release Time Unscheduled Channel Algorithm in OBS WDM Networks (OBS WDM 망에서 비 할당된 채널 개방시간을 이용한 효율적인 채널 스케줄링 기법)

  • Cho Seok-man;Kim Sun-myeng;Choi Dug-kyoo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.10A
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    • pp.912-921
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    • 2005
  • Optical burst switching(OBS) is a promising solution for building terabit optical routers and realizing If over WDM. Channel scheduling Algorithm for reduce contention is one of the major challenges in OBS. We address the issue of how to provide basic burst channel scheduling in optical burst switched WDM networks with fiber delay lines(FDLs). In OBS networks the control and payload components or a burst are sent separately with a time gap. If CHP arrives to burst switch node, because using scheduling algorithm for data burst, reservation resources such as wavelength and transmit data burst without O/E/O conversion, because contention and void between burst are happened at channel scheduling process for data burst that happened the link utilization and bust drop probability Existent proposed methods are become much research to solve these problems. Propose channel scheduling algorithm that use Release Time of bust to emphasize clearance between data and data dissipation that is happened in data assignment in this treatise and maximize bust drop probability and the resources use rate (RTUC : Release Time Unscheduled Channel). As simulation results, Confirmed that is more superior in terms of data drop and link utilization than scheduling algorithm that is proposed existing. As simulation results, confirmed improved performance than scheduling algorithm that is proposed existing in terms of survival of burst, efficiency resource and delay. However, In case load were less, degradation confirmed than existent scheduling algorithm relatively, and confirmed that is superior in data drop aspect in case of load increased.

Respiratory burst activity of tilapia (Oreochromis mosambicus) phagocytes to Edwardsiella tarda ghosts

  • Kim, Gi-Hong;Kwon, Se-Ryeon;Nam, Yun-Kwon;Lee, Eun-Hye;Kim, Min-Sun
    • Journal of fish pathology
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    • v.19 no.3
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    • pp.285-288
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    • 2006
  • The respiratory burst activity of tilapia (Oreochromis mosambicus) phagocytes agaisnt Edwardsiella tarda ghosts produced by gene E mediated lysis was investigated. Stimulation with E. tarda ghosts (ETG) showed markedly higher respiratory burst activity than that with formalin killed E. tarda (FKC) in phagocytes. This result may suggest that ETG can induce effective cellular immune responses in fish.

The Improved NAV Update method for Transmit of Fragmented Burst in Multirate WLAN environment (Multirate 무선랜 환경에서 Fragment Burst의 전송을 위한 개선된 NAV Update 방법)

  • 김태환;송경희;박동선
    • Proceedings of the IEEK Conference
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    • 2003.07a
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    • pp.53-56
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    • 2003
  • In order to enhance the system capacity of multi rate IEEE 802.11 WLAN, we propose the transmission rate select method using the control frame in this paper. The transmission rate is selected dynamically based on the RSSI(Received Signal Strength Indicator) of received control frame. And we also propose the Enhanced NAV Update method for Fragmented MPDU burst transmission in multirate WLAN environment. This method can improve the system capacity by support the burst transmission of fragmented MPDU.

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Frequency Response Characteristics by Using Tone-Burst Method for Piezoelectric Ceramic Transducer (압전 세라믹 트랜스듀서의 Tone-Burst법에 의한 주파수 응답특성)

  • Bae, Hyo-Yoon;SaGong, Geon
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.806-809
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    • 1988
  • The frequency response characteristics of a bimorph type PZT piezoelectric transducer was investigated. In this study, function generator which generates short burst signal, plane reflection plate and oscilloscope were used to measure the characteristics of piezoceramic ultrasonic transducer. The resonant frequency of a bimorph type piezoceramic transducer which is acquired by using Tone-Burst Method had good agreement with the measured results from spectrum analyzer.

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Mechanism of Glucose Uptake on PMA Stimulated Neutrophils (PMA에 의한 중성구의 당섭취 기전 연구)

  • Paik, Jin-Young;Ko, Bong-Ho;Yoo, Man-Kil;Jin, Kwang-Ho
    • Korean Journal of Clinical Laboratory Science
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    • v.39 no.3
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    • pp.249-255
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    • 2007
  • While respiratory burst enhances neutrophil glucose utilization, many neutrophil functions are critically influenced by extracellular matrix interaction and phosphoinositide-3-OH kinase (PI3K) signaling. We thus evaluated the role of RGD integrin occupancy and PI3K inhibition on respiratory burst and [18F]FDG uptake of stimulated neutrophils. Human neutrophils were stimulated by 100 ng/mL phorbol-myristate-acetate (PMA), and respiratory burst was measured by cumulative luminescence with lucigenin. [18F]FDG uptake and total hexokinase activity was measured 20 min after PMA stimulation in the presence or absence of soluble RGD peptides (200 g/mL) and/or the PI3K inhibitor wortmannin (200 nM). PMA induced a 71.70.9 fold increase in neutrophil oxygen intermediate generation. [18F]FDG uptake was increased to $194.6{\pm} 3.7%$ and hexokinase activity to $145.0{\pm}2.0%$ of basal levels (both p<0.0005). RGD peptides attenuated respiratory burst activation to $35.6{\pm}0.2%$ (p<0.005), but did not inhibit stimulated [18F]FDG uptake or hexokinase activity. In contrast, without affecting respiratory burst activation, wortmannin inhibited PMA stimulated [18F]FDG uptake to $66.9{\pm}1.6%$ and hexokinase activity to $81.0{\pm}4.2%$ (both P<0.0005), demonstrating its dependence on PI3K activity. Neither RGD nor wortmannin reversed the other's inhibitory effect on stimulated [18F]FDG uptake and hexokinase activity or respiratory burst, which suggests the involvement of distinct signaling pathways. Neutrophil [18F]FDG uptake is enhanced by PMA through a mechanism that requires PI3K activity but is independent of integrin receptor occupancy or respiratory burst activation.

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EMR: An effective method for monitoring and warning of rock burst hazard

  • Song, Dazhao;Wang, Enyuan;Li, Zhonghui;Qiu, Liming;Xu, Zhaoyong
    • Geomechanics and Engineering
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    • v.12 no.1
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    • pp.53-69
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    • 2017
  • Rock burst may cause serious casualties and property losses, and how to conduct effective monitoring and warning is the key to avoid this disaster. In this paper, we reviewed both the rock burst mechanism and the principle of using electromagnetic radiation (EMR) from coal rock to monitor and forewarn rock burst, and systematically studied EMR monitored data of 4 rock bursts of Qianqiu Coal Mine, Yima Coal Group, Co. Ltd. Results show that (1) Before rock burst occurrence, there is a breeding process for stress accumulation and energy concentration inside the coal rock mass subject to external stresses, which causes it to crack, emitting a large amount of EMR; when the EMR level reaches a certain intensity, which reveals that deformation and fracture inside the coal rock mass have become serious, rock burst may occur anytime and it's necessary to implement an early warning. (2) Monitored EMR indicators such as its intensity and pulses amount are well and positively correlated before rock bursts occurs, generally showing a rising trend for more than 5 continuous days either slowly or dramatically, and the disaster bursts generally occurs at the lower level within 48 h after reaching its peak intensity. (3) The rank of EMR signals sensitive to rock burst in a descending order is maximum EMR intensity > rate of change in EMR intensity > maximum amount of EMR pulses > rate of change in the amount of EMR pulses.

QoS Improvement Scheme in Optical Burst Switching using Dynamic Burst length Adjustment (광 버스트 스위칭에서 버스트 길이의 동적 조절을 통한 QoS 향상방법)

  • Sanghoon Hong;Lee, Sungchang
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.40 no.12
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    • pp.136-144
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    • 2003
  • In this paper, we propose a scheme that can control the loss probability of low priority class bursts by dynamically adjusting the assembly threshold of low priority class. The key ideas is that the loss Probability of the longer burst increases as the load increases, thus reduced low priority class burst length decreases the loss priority at high traffic load. To achieve this aim, we first derive the relation among the loss probability, the assembly threshold, and the traffic load. In this paper we derive the relation by curve fitting on the simulation results. The ingress edge routers periodically or by event-driven receives the proper corresponding assembly threshold information from the core routers. This assembly threshold is calculated from the derived relation so that the required loss probability of the low priority class bursts in the network is satisfied. The simulation results show that the proposed scheme performs well to meet the loss probability target as expected.