• 제목/요약/키워드: Head Distribution

검색결과 915건 처리시간 0.025초

QUEUEING ANALYSIS OF THE HOL PRIORITY LEAKY BUCKET SCHEME

  • Choi, Doo-Il
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제7권1호
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    • pp.15-23
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    • 2003
  • ATM networks provide the various kinds of service which require the different Quality of Services(QoS) such as loss and delay. By statistically multiplexing of traffics and the uncertainty and fluctuation of source traffic pattern, the congestion may occur. The leaky bucket scheme is a representative policing mechanism for preventive congestion control. In this paper, we analyze the HOL(Head-of-Line) priority leaky bucket scheme. That is, traffics are classified into real-time and nonreal-time traffic. The real-time traffic has priority over nonreal-time traffic for transmission. For proposed mechanism, we obtain the system state distribution, finally the loss probability and the mean waiting time of real-time and nonreal-time traffic. The simple numerical examples also are presented.

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스테인리스강의 크리프 특성치와 파단시간과의 관계 (Relationship between Creep Characteristic Values and Rupture time in STS304 Stainless Steels)

  • 공유식;김선진;이배섭
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2004년도 학술대회지
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    • pp.228-233
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    • 2004
  • The characteristics of the probability distribution for mechanical properties, e.g. tensile strength, reduction of area ana elongation, for STS304 stainless steel in elevated temperature were investigated from tensile test performed by constant cross head speea controls with 1mm/min, Recently, in order to clarify the strengthening mechanisms at high temperature, a new scheme to improve high temperature mechanical properties is desired. Therefore, the test ,technique development of high temperature creep behaviors for this material is very important. In this paper, the creep praperties and creep life prediction by Larson-Miller parameter method for STS304 stainless steel to be used for other high temperature components were presented at the elevated temperatures of 600, 650 and $700^{\circ}C$.

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오일 소모 저감을 위한 역단류 2행정 프리피스톤 수소기관의 분리 윤활 특성 해석 (An Analysis on Charateristics of Separate Oiling to Reduce Oil Consumption for a 2 Stroke Free-Piston H2 Engine)

  • 변창희;백대하;이종태
    • 한국수소및신에너지학회논문집
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    • 제22권6호
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    • pp.794-799
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    • 2011
  • In order to reduce the oil consumption for a 2 stroke free piston hydrogen fueled engine, the behaviors of residual lubricant oil of the cylinder wall surface were visualized and oil mass emitted into exhaust port was measured by using research engine with cross-head and eccentric crankshaft. As the results, it was shown that characteristics of residual lubricant oil such as oil thickness and distribution were remarkably different from a conventional 4 stroke engine. It was also analyzed that these tendencies relied on the configuration and installed position of the exhaust port, piston pin boss and so on.

규칙파중(規則波中)에서의 쌍동선(雙胴船)의 수직운동성능계산(垂直運動性能計算) (The Vertical Motion Calculation of a Catamaran in Regular Waves)

  • 윤길수;최항순;이기표
    • 대한조선학회지
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    • 제19권4호
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    • pp.47-52
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    • 1982
  • The present paper gives numerical results of 2-D hydrodynamic forces on twin cylinders oscillating on a free surface in a deep water. The singularity distribution method is applied to determine a stream function. Based on the 2-D results the vertical motion responses of a catamaran model(ASR 5061) moving in regular head seas are estimated by using Ordinary Strip Method(O.S.M.). Numerical results show in general good agreements with Jones' theoretical and experimental results except those the resonance frequency.

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Experimental Investigation of Electrostatic Dripping and Atomization Mode through Non-MEMs based Nozzle Design

  • Choi, Kyung-Hyun;Dang, Hyun-Woo;Rehmani, M.A. Ali
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2009년도 춘계학술발표대회
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    • pp.13.2-13.2
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    • 2009
  • Electrostatic printing either it is drop-on-demand or continuous has immense applications in non-contact printing systems such as solar cells, flexible printed circuits, RFIDs and bio applications. In this paper a laboratory manufactured nozzle has been designed for the experimental investigation of electrostatic dripping and atomization of liquid. Dripping and atomization conditions such as voltage, nozzle tip diameter, distance between counter electrode and flowrate has been indentified for the designed nozzle. Furthermore it is also demonstrated that the diameter of a generated droplet could be reduced from a significantly large size to a narrow size distribution which can be controlled by volumetric flow rate and applied voltage. This study will help in classify the conditions between different electrostatic dripping mode such as drop-on-demand formation, jet mode and finally the atomization mode based on the laboratory fabricated nozzle head.

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시각 및 청각 되먹임을 통한 뇌성마비 아동의 좌우 대칭척 서기 자세 훈련 효과 (The Effect of Symmetrical Standing Posture in Cerebral Palsied Children after Visual and Auditory Feedback Training)

  • 김유현;박관수;천미혜;김종만
    • 한국전문물리치료학회지
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    • 제1권1호
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    • pp.17-24
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    • 1994
  • Biofeedback devices have been used successfully to improve head control and symmetrical walking in cerebral palsied children. Biofeedback of postural sway was investigated as a therapeutic technique to reduce postural abnormality in 24 selected children with cerebral palsy. Subjects were evaluated their weight distribution of both sides during their standing before and after the visual and auditory feedback training. The effectiveness of biofeedback was compared to conventional physical therapy practices in reestabilishing symmetrical standing in cerebral palsied children. Our study found biofeedback was effective in training symmetrical standing posture.

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경계요소법에 의한 터보과급 가솔린기관 실린더헤드에 대한 열전도 해석 (Heat Conduction Analysis of the Cylinder Head in Turbocharged Gasoline Engine by Boundary Element Method)

  • 최영돈;홍진관
    • 대한기계학회논문집
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    • 제13권4호
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    • pp.739-752
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    • 1989
  • 본 해석의 목적은 실린더헤드의 3차원 열전도해석을 격자망구성이 편리한 경계요소법을 이용하여 수행함으로써 연소실의 벽면온도를 구하여 연소 실내의 열전달과정 해석을 위한 사이클 시뮬레이션에 사용하는데 있다.

무선통신 단말기의 SAR 저감법 (Method of SAR reduction for Wireless Transceiver)

  • 황재호
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2005년도 춘계종합학술대회
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    • pp.346-349
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    • 2005
  • 본 논문은 무선통신용 휴대단말기를 설계하는데 있어 인체 전자파 흡수율(SAR)을 저감시키는 방법을 제안한다. 단말기의 안테나로부터 방사되는 전자파에너지는 휴대단말기 기구의 특정부분에 밀집되는데 이와 같은 전계강도는 인체의 두부에 영향을 미쳐 SAR값의 증가 요소로 작용한다. 이를 감소시키는 방법으로는 표면전계가 밀집되지 않는 구조의 기구 설계법을 제시한다. 안테나를 포함한 단말기의 해석은 유한요소법(FEM)을 사용하였으며, 본 저감법를 적용한 경우 SAR첨두치의 약50 %를 저감하는 효과가 나타났다.

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비전 기반 움직임 영역 탐지를 이용한 전차 승무원 보호 시스템 개발 (Development of a Tank Crew Protection System Using Moving Object Area Detection from Vision based)

  • 최광모;장동식
    • 한국군사과학기술학회지
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    • 제8권2호
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    • pp.14-21
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    • 2005
  • This paper describes the system for detecting the tank crew's(loader's) hand, arm, head and the upper half of the body in a danger area between the turret ceiling and the upper breech mechanism by computer vision-based method. This system informs danger of pressed to death to gunner and commander for the safety of operating mission. The camera mounted ort the top portion of the turret ceiling. The system sets search moving object from this image and detects by using change of image, laplacian operator and clustering algorithm in this area. It alarms the tank crews when it's judged that dangerous situation for operating mission. The result In this experiment shows that the detection rate maintains in $81{\sim}98$ percents.

배전용 현수애자의 특성분석 (Characteristic Analysis of Suspension Insulators for Distribution Line)

  • 김찬영;김주용;송일근;이병성
    • 한국전기전자재료학회논문지
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    • 제13권3호
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    • pp.259-264
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    • 2000
  • The paper provides the characteristic analyses of porcelain suspension insulators. The comparisons of characteristics were made as a function of failed and unfailed insulators which had ben used in the fields. This paper also describes the failure modes occurred in the fields. The aging of cement corrosion of metal breaking of shed puncture in the head and separation of glaze are different failure modes for porcelain suspension insulators. Among these failure modes the puncture breaking and glaze problems were major concerns in this research. The cracks porosities of porcelain and micro-crystals on the graze were the causes of these failures. These results were confirmed by conducting various failure analyses.

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