• Title/Summary/Keyword: HiLow

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Molecular gas properties under ICM pressure : A Case study of NGC4402

  • Hahn, You-Jin;Chung, Ae-Ree
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.117.2-117.2
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    • 2011
  • We probe 12CO J=2-1 and 13CO J=1-0 properties of a Virgo disk galaxy, NGC 4402 which is located near the cluster center. Our goal is to study the impact of intra cluster medium (ICM) on the molecular gas of a galaxy in the cluster environment. It has been believed that cluster galaxies are deficient in atomic hydrogen gas (HI gas) compared to their field counterparts and now there is much evidence that low density ISM can be easily removed by ram pressure caused by ICM wind. Meanwhile, no significant molecular gas deficiency of the cluster galaxy population has been found yet they show overall lower star formation rate than galaxies in the field, and it is still controversy whether dense ISM can be also stripped by the ICM wind or not. NGC 4402 with truncated HI disk($D_{HI}/D_{opt}$ ~ 0.75 and only 36%of HI gas compare to field galaxies of a similar size) and a disturbed gas morphology, appears to have strong ongoing ram pressure. Using high resolution 12 and 13CO data of NGC 4402 from a Sub Millimeter Array (SMA), we probe the molecular gas properties under strong ICM pressure. We discuss how its star formation activity and hence the global color of NGC4402 would be changed in the future.

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A High-speed 8-Bit Current-Mode BICMOS A/D Converter (BICMOS를 이용한 전류형 고속 8비트 A/D변환기)

  • Han, Tae-Hi;Cho, Sang-Woo;Lee, Heui-Deok;Han, Chul-Hi
    • Proceedings of the KIEE Conference
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    • 1991.07a
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    • pp.857-860
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    • 1991
  • This paper describes a High-Speed 8-bit Current-Mode BiCMOS A/D Converter. The characteristics of this A/D Converter are as fellows. First, as ADC is operating in current-mode we can obtain the properties of increase of converting speed, low noise, and wideband. Second, the properties of high switching speed in bipolar transistor and of high packing density, low power consumption in MOS trnsistor are combined. Finally we reduce chip area by designing it with subranging mode and improve the converting speed by performing subtraction directly, which doesn't need D/A convertings, using current switching element. This converter is composed of two 4-bit ADC, current soure array which provides signal and reference current, current comparator and encoding network.

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Low Cycle Fatigue of PPS Polymer Injection Welds (I) -Fatigue Crack Behavior-

  • Song, Jun-Hee;Lim, Jae-Kyoo;Kim, Yon-Jig;Kim, Hong-Gun
    • Journal of Mechanical Science and Technology
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    • v.17 no.5
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    • pp.647-653
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    • 2003
  • An important class of short-fiber reinforced composites is the sheet molding compound, which is recently developed and currently used in many engineering applications. Fatigue failure of the composites is a subject of major concern in design and cyclic crack propagation is of particular significance in the fatigue life prediction of short fiber composites. However, research on the fatigue behavior of polymer injection weld, especially short glass fiber-filled polymer injection weld, has not been carried out. In this study the analyses of the fatigue crack growth behaviors at weld line and in the bulk are performed based on low cycle fatigue test.

무선센서네트워크 환경에서 계층적 라우팅 프로토콜의 성능개선을 위한 Short-cut 라우팅 알고리즘

  • Gang, Mun-Gyeong;Jan, Gyo-Hong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2007.10a
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    • pp.526-529
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    • 2007
  • 무선센서네트워크 환경에서 활용될 수 잇는 대표적인 계층적 라우팅 프로토콜로는 Zigbee(지그비) 계층구조 라우팅과 IETF의 6LoWPAN WG에 드래프트로 제출되었던 HiLow 프로토콜 등이 있다. 이들 계층구조 라우팅 프로토콜은 깊이 우선(Depth-first) 방식과 폭 우선(Width-first) 방식을 각각 사용하여 자동 주소 할당을 수행한 후 이를 이용해 계층적 경로 배정이 되도록 한다. 이에 따라 망상의 노드들이 물리적으로 가까운 위치에 존재하더라도 경로는 계층적으로 제공되어 데이터 전달에 많은 흡 수가 소요된다. 본 논문에서는 이러한 경로 배정 시 발생되는 비효율성을 개선하고 싱크(Sink) 주위 노드의 에너지 소모율을 줄일 수 있는 경로 배정 알고리즘을 제안한다.

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Serological study on canine parvovirus in the puppies (신생자견에 있어서 Canine parvovirus에 대한 혈청학적 연구)

  • 박경옥;김상윤;조옥숙;김정화;김대원
    • Korean Journal of Veterinary Service
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    • v.21 no.1
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    • pp.87-95
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    • 1998
  • The present study was conducted to characterize maternal antibody status which haemagglutination inhibition(HI) titers against canine parvovirus(CPV) in the 15 puppies delivered from 3 dams. The range of HI titers of 5 puppies delivered from a mother dog(A) with HI titer of 1 : 1,024 were 1 : 16~1 : 64 at 1 day old before suckling, 1 : 512~1 : 1,024 at 2 days old after suckling, 1 : 512~1 : 2,048 at 1 week old, 1 : 256~l : 1,024 at 2 weeks old, 1 : 128~l : 512 at 3 weeks old, 1 : 128~l : 256 at 4 weeks old, 1 : 32~1 : 128 at 5 weeks old, 1 : 16~1 : 64 at 6 weeks old, 1 : 16~1 : 64 at 7 weeks old, and 1 : 16~l : 32 at 8 weeks old. After vaccination with DHPPL to canine parvovirus in 60 days and 80 days old puppies, 1 : 8~l : 32 at 9 weeks old, 1 :16~1 : 128 at 10 weeks old, 1 : 32~1 : 256 at 11 weeks old, 1 : 16~1 : 256 at 12 weeks old, 1 : 128~1 : 256 at 13 weeks old, 1 : 64~l : 512 at 14 weeks old, and 1 : 128~1 : 512 at 15 weeks old. The HI titers of 3 puppies delivered from a mother dog(B) with HI titer of 1 : 512 were 1 : 16 at 1 day old before suckling, 1 : 256~1 : 512 at 2 days old after suckling, 1 : 512 at 1 week old, 1 : 128~1 : 256 at 2 weeks old, 1 : 64~1 : 128 at 3 weeks old, 1 : 64~1 : 128 at 4 weeks old, 1 : 128 at 5 weeks old, 1 : 64~1 : 128 at 6 weeks old, 1 : 16 at 7 weeks old, and 1 : 8 at 8 weeks old. After vaccination with DHPPL to canine parvovirus in 60 day and 80 days old puppies, < : 8~l : 8 at 9 weeks old, < : 8 ~1 : 16 at 10 weeksold, 1 : 64~1 : 128 at 11 weeks old, and 1 : 256~1 : 512 at 12 weeks old. The HI titers of 7 puppies delivered from mother dog(C) with Hl titer 1 : 1,024 were 1 : 512~1 : 1,024 at 2 days old after suckling, 1 : 256~1 : 1,024 at 1 week old, 1 : 256~l : 1,024 at 2 weeks old, 1 : 64~1 : 512 at 3 weeks old, 1 : 64~1 : 512 at 4weeks old, 1 : 8~l : 64 at 5 weeks old, 1 : 8~1 : 64 at 6weeks old, 1 : 8~1 : 32 at 7 weeks old, and < : 8~1 : 8 at 8 weeks old. Antibody to CPV was transferred mainly from mother to progeny through the colostrum and the transferred maternal antibody was in proportion to the HI titer of the mother As the HI titer of maternal antibody in puppies was low, puppies have a rapid immune response and a massive rise in HI titer to vaccination against CPV compared with puppies haying high level of maternal antibody.

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Simulation Study of Energy-efficient Routing Algorithm in Hierarchical WSN Environments (계층적 구조의 WSN 환경에서 에너지 효율적인 라우팅 알고리즘의 시뮬레이션 연구)

  • Kang, Moon-Kyoung;Jin, Kyo-Hong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.8
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    • pp.1729-1735
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    • 2009
  • The hierarchical routing could cause a lot of energy consumption for transferring data by assigning hierarchical routes although actual nodes could be located in physically near spots. Also, when Node Failure or Association Error occurs, the Hierarchical routing could waste more energy to deliver the control messages. This paper evaluate performance of SHP(Shortest Hop Routing) algorithm that suggests short-cut routing algorithm using NL(Neighbor List) and Redirect_ACK message to improve problem of hierarchical routing algorithm. We do a computer simulation by the size of network, deployment of sensor nodes, sink position and POS. As a result of simulation, SHP has better performance than Zigbee Hierarchical routing and HiLow.

Verification of Hi9h Impedance Fault Relay through Low Voltage Power System Implementation (저압모의계통 구성을 통한 고저항지락사고 검출용 계전기의 실계통 적응성 검증)

  • Hong, Sun-Chun;Jang, Byung-Tae;Yoo, Heung-Jun
    • Proceedings of the KIEE Conference
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    • 1999.07c
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    • pp.1437-1439
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    • 1999
  • This paper describes test method though low voltage power system implementation for high impedance fault relay test before its operation in real power system. Through this test, relay tested its function and algorithm. In this paper, we will provides test method using low voltage power system and its results.

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