• 제목/요약/키워드: Narrow Channel

검색결과 359건 처리시간 0.029초

LAN을 이용한 VOD 시스템의 구현 (Implementation of VOD System Using LAN)

  • 김윤범;인준형;최윤식;이정수
    • 방송공학회논문지
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    • 제1권2호
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    • pp.133-141
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    • 1996
  • 본 논문에서는 차세대 영상 서비스 기술인 VOD(Video-on-Demand)시스템을 LAN을 이용하여 구현하였다. LAN을 이용한 VOD 시스템은 네트워크 병목현상과 이에 따른 시간 지연 때문에 기존의 네트워크 구현으로는 원활한 서비스가 되지 못하므로, 그러한 문제점을 해결하기 위한 방안으로, 본 논문에서는 토팔러지의 변경과 그에 따른 네트워크 장비의 선정, 개선된 프로토콜의 제정 등이 제시되었다. 결론적으로 구현된 시스템은 세그먼트 당 최대 3∼4명의 클라이언트를 수용할 수 있었고, 전송하고자 하는 영상 데이터의 크기에 따라 미리 네트워크 버퍼의 크기를 최적화하는 것이 서비스의 품질을 높이는데 필수적이라는 것을 알 수 있었다.

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울돌목 조류에너지 개발 현황과 전망 (Development of Uldolmok Tidal Current Energy)

  • 이광수;염기대;박진순;강석구;박우선;한상훈;정공일;박정우
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2005년도 춘계학술대회
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    • pp.512-515
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    • 2005
  • The Korean peninsula has a number of coastal sites where the rhythmic rising and lowering of water surface due to tides result in strong tidal current. The kinetic energy of these currents can be efficiently exploited by using tidal current turbines. The pilot tidal current power plant is to be constructed at the Uldolmok between Chindo and Haenam. Extensive coastal engineer ing research works have been carried out. This paper describes some observation results of field campaign, design of the supporting structure of a pilot plant of 1,000kW and a future tidal current power plant and so on.

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울돌목 조류발전의 연안물리적 관점에서의 고찰 (Coastal-physical cceanographic aspects in relation to the tidal current power generation in the Uldolmok)

  • 염기대;이광수;박진순;강석구
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2005년도 춘계학술대회
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    • pp.516-519
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    • 2005
  • The pilot tidal current power plant is to be constructed at the Uldolmok between Chindo and Haenam, during next year. and extensive coastal engineering research works have been carried out. In this paper we describes some observation results of the tide and tidal current. as well as modeling work in order to investigate the tide and tidal current regime change in relation to the tidal current power plant (TCPP) construction. The special modeling skill in order to consider the turbine operation in the TCPP is developed and applied to the estimation for the flow regime change by the simple layout of the tidal current power plant.

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목포항에서의 풍파로 인한 범람 (Wave Inundation at Mokpo Harbor)

  • 이정렬;강주환;문승록;임흥수
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2006년도 학술발표회 논문집
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    • pp.574-578
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    • 2006
  • Tidal amplification by construction of the sea-dike and sea-walls had been detected not only near Mokpo Harbor but also at Chungkye Bay which is connected with Mokpo Harbor by a narrow channel. This brings about increase of tidal flat area and in particular increase of surge-wave combined runup during storms. The purpose of this study is to examine an efficient operational model that can be used by civil defense agencies for real-time prediction and fast warnings on wind waves and storm surges. Instead of using commercialized wave models such as WAM, SWAN, the wind waves are simulated by using a new concept of wavelength modulation to enhance broader application of the hyperbolic wave model of the mild-slope equation type. Furthermore, The predicting system is composed of easy and economical tools for inputting depth data of complex bathymetry and enormous tidal flats such as Mokpo coastal zone. The method is applied to Chungkye Bay, and possible inundation features at Mokpo Harbor are analyzed.

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울돌목 조류발전의 연안물리적 관점에서의 고찰 (Coastal-physical cceanographic aspects in relation to the tidal current power generation in the Uldolmok)

  • 강석구;염기대;이광수;박진순
    • 신재생에너지
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    • 제1권2호
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    • pp.73-78
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    • 2005
  • The pilot tidal current power plant is to be constructed at the Uldolmok between Chindo and Haenam, during next year, and extensive coastal engineering research works have been carried out. In this paper we describes some observation results of the tide and tidal current, as well as modeling work in order to investigate the tide and tidal current regime change In relation to the tidal current power plant [TCPP] construction. The special modeling skill in order to consider the turbine operation in the TCPP is developed and applied to the estimation for the flow regime change by the simple layout of the tidal current power plant.

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벌크 FinFET의 기술 동향 및 이슈 (Trend and issues of the bulk FinFET)

  • 이종호;최규봉
    • 진공이야기
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    • 제3권1호
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    • pp.16-21
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    • 2016
  • FinFETs are able to be scaled down to 22 nm and beyond while suppressing effectively short channel effect, and have superior performance compared to 2-dimensional (2-D) MOSFETs. Bulk FinFETs are built on bulk Si wafers which have less defect density and lower cost than SOI(Silicon-On-Insulator) wafers. In contrast to SOI FinFETs, bulk FinFETs have no floating body effect and better heat transfer rate to the substrate while keeping nearly the same scalability. The bulk FinFET has been developed at 14 nm technology node, and applied in mass production of AP and CPU since 2015. In the development of the bulk FinFETs at 10 nm and beyond, self-heating effects (SHE) is becoming important. Accurate control of device geometry and threshold voltage between devices is also important. The random telegraph noise (RTN) would be problematic in scaled FinFET which has narrow fin width and small fin height.

예혼합화염의 불안정성 및 비선형적 거동에 관한 수치적 연구 (Numerical Study on the Premixed Flame Instability and Nonlinear Behavior)

  • 강상훈;백승욱;임홍근
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2005년도 제31회 KOSCO SYMPOSIUM 논문집
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    • pp.281-286
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    • 2005
  • To understand fundamental characteristics of combustion in a small scale device, the effects of the momentum and heat loss on the stability of laminar premixed flames in a narrow channel are investigated by two-dimensional high-fidelity numerical simulation. A general finding is that momentum loss promotes the Saffman-Taylor (S-T) instability which is additive to the Darrieus-Landau (D-L) instabilities, while the heat loss effects result in an enhancement of the diffusive-thermal (D-T) instability. These effects are also valid in nonlinear behavior of the premixed flame. The simulations of multiple cell interactions are also conducted with heat and momentum loss effects.

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다치 직교 PRS 신호에 대한 잡음과 간섭 및 캐리어 옵셋의 영향 (The Effects of Noise, Interference, and Carrier Offset on Multi-Level QPRS Signals)

  • 이광렬;조성준
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(II)
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    • pp.869-873
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    • 1987
  • In this study, we have examined the multi-level QPRS system in point of error rate, which requires narrow bandwidth and has Little ISI. The generalized error rate equations of multi-level QPRS signal have been derived in the presence of Gaussian noise and co-channel CW interference. And the error rate performance of 9, 49, 225 QPRS system is investigated as parameters of carrier power-to-noise power, carrier power-to -interference power. Also, we have investigated the effect of carrier offset.

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간극에서의 역방향 유동 제한 현상 연구 (Counter-Current Flow Limit in Narrow Gap)

  • 김용훈;서균렬
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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    • pp.1054-1060
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    • 1998
  • Previous counter-current flow limitation (CCFL) and critical heat flux (CHF) studies included investigations on the inlet entrance, inclined channel and gap effects for the most part. In this study, the local CHF correlation was presented to be used in the numerical analysis for the 3 dimensional hemispherical geometry. Also, first-principle analyses were performed to determine the maximum heat removal capability from the debris through the gap that may be formed during a core melt accident. The maximum heat removal capability by gap cooling can be applied in quantitatively assessing the severe accident management measures.

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Co-sputtering of Microcrystalline SiGe Thin Films for Optoelectronic Devices

  • 김선조;김형준;김도영
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2011년도 춘계학술발표대회
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    • pp.64.2-64.2
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    • 2011
  • Recently, Silicon Germanium (SiGe) alloys have been received considerable attention for their great potentials in advanced electronic and optoelectronic devices. Especially, microcrystalline SiGe is a good channel material for thin film transistor due to its advantages such as narrow and variable band gap and process compatibility with Si based integrated circuits. In this work, microcrystalline silicon-germanium films (${\mu}c$-SiGe) were deposited by DC/RF magnetron co-sputtering method using Si and Ge target on Corning glass substrates. The film composition was controlled by changing DC and RF powers applied to each target. The substrate temperatures were changed from $100^{\circ}C$ to $450^{\circ}C$. The microstructure of the thin films was analyzed by x-ray diffraction (XRD) and Raman spectroscopy. The analysis results showed that the crystallinity of the films enhances with increasing Ge mole fraction. Also, crystallization temperature was reduced to $300^{\circ}C$ with $H_2$ dilution. Hall measurements indicated that the electrical properties were improved by Ge alloying.

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