• 제목/요약/키워드: central line

검색결과 917건 처리시간 0.033초

FAR-INFRARED [C II] EMISSION FROM THE CENTRAL REGIONS OF SPIRAL GALAXIES

  • MOCHIZUKI KENJI
    • 천문학회지
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    • 제37권4호
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    • pp.193-197
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    • 2004
  • Anomalies in the far-infrared [C II] 158 ${\mu}m$ line emission observed in the central one-kiloparsec regions of spiral galaxies are reviewed. Low far-infrared intensity ratios of the [C II] line to the continuum were observed in the center of the Milky Way, because the heating ratio of the gas to the dust is reduced by the soft interstellar radiation field due to late-type stars in the Galactic bulge. In contrast, such low line-to-continuum ratios were not obtained in the center of the nearby spiral M31, in spite of its bright bulge. A comparison with numerical simulations showed that a typical column density of the neutral interstellar medium between illuminating sources at $hv {\~} 1 eV $ is $N_H {\le}10^{21}\;cm^{-2}$ in the region; the medium is translucent for photons sufficiently energetic to heat the grains but not sufficiently energetic to heat the gas. This interpretation is consistent with the combination of the extremely high [C Il]/CO J = 1-0 line intensity ratios and the low recent star-forming activity in the region; the neutral interstellar medium is not sufficiently opaque to protect the species even against the moderately intense incident UV radiation. The above results were unexpected from classical views of the [C II] emission, which was generally considered to trace intense interstellar UV radiation enhanced by active star formation.

Baseline-free damage detection method for beam structures based on an actual influence line

  • Wang, Ning-Bo;Ren, Wei-Xin;Huang, Tian-Li
    • Smart Structures and Systems
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    • 제24권4호
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    • pp.475-490
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    • 2019
  • The detection of structural damage without a priori information on the healthy state is challenging. In order to address the issue, the study presents a baseline-free approach to detect damage in beam structures based on an actual influence line. In particular, a multi-segment function-fitting calculation is developed to extract the actual deflection influence line (DIL) of a damaged beam from bridge responses due to a passing vehicle. An intact basis function based on the measurement position is introduced. The damage index is defined as the difference between the actual DIL and a constructed function related to the intact basis, and the damage location is indicated based on the local peak value of the damage index curve. The damage basis function is formulated by using the detected damage location. Based on the intact and damage basis functions, damage severity is quantified by fitting the actual DIL using the least-square calculation. Both numerical and experimental examples are provided to investigate the feasibility of the proposed method. The results indicate that the present baseline-free approach is effective in detecting the damage of beam structures.

Line Profiles of the Saturn Ring Planetary Nebula

  • 이성재;형식
    • 천문학회보
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    • 제36권2호
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    • pp.115.1-115.1
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    • 2011
  • We analyzed the line profiles of the planetary nebula (PN) NGC 7009 secured with the Keck I HIES and BOES's spectral data. The 5 positions were taken over the nebular image, 4 points on the bright rim plus 1 point at the central position. The covered spectral wavelength range was $3250{\AA}-8725{\AA}$ in these observations. We decomposed the lines of HI, HeI, HeII, CII, NIII, [ClIII], [NII], [OII], [OIII], [SII], [SIII], [ClIII], and [ArIII] using the IRAF and StarLink/Dipso. After correcting the Earth's movement and the PN's radial velocities, -48.6 & -48.9 km/s, respectively, for the Keck & BOES, we produced the line profiles in a velocity scale. The zero velocity at each line profile clearly indicates which part of the components is approaching or receding, giving a general information of the kinematical structure. Almost all of the low-to-medium excitation lines, such as [NII], [SII], [O III], and [ArIII], secured at the central position and four positions along the major & minor axes, showed 3 components, double peak + a wide wing component, suggesting the fast outflow structures are present. The overall geometry is a prolate shell which also has a fainter outer shell in the halo zone, but there appears to be some peculiar sub-structures inside the main shell. The high excitation He I, HeII, NIII lines which might be formed close to the inner boundary of the shell show unusual features, completely different from the other lines. The HeII and these high excitation lines may be indicative of a relative recent fast outflow from the central star and the permitted lines such as NIII might be affected by the innermost structure. We discuss a possible presence of a jet-like fast outflow structure in an out-flow axis different from the main axis of the spheroid shell.

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Intel486 병렬시스템의 Cache Coherence를 위한 Central Directory Unit의 설계 (Design of Central Directory Unit for Cache Coherence of Multiprocessor based on Intel486 Microprocessor)

  • 유준복;정태상
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 D
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    • pp.2684-2686
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    • 2001
  • In order to utilize cache in multiprocessor system, cache coherence problem must be handled. Central directory scheme is one of hardware-assisted cache coherence solutions. The goal of this paper was not only to propose some special methods needed to apply central directory scheme to the specific multiprocessor system based on Intel486 microprocessors but also to design central directory unit for cache coherence of the target system. The problems of arbitrating several requests from processors, storing the cache information, and generating control signals for cache line fill and snoop cycle were solved.

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Gravimetrics of Pupal Weight Loss in the Domestic Silkworm, Bombyx mori Linn. (Lepidoptera : Bombycidae)

  • Kumar, Vineet;Kariappa, B.K.;Chaturvedi, H.K.;Sarkar, A.;Datta, R.K.
    • International Journal of Industrial Entomology and Biomaterials
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    • 제1권1호
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    • pp.25-28
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    • 2000
  • A comprehensive study on daily pupal weight loss due to histolysis and histgenesis in Bombyx mori Linn., has been undertaken. The percentag of pupal weight loss in the male pupa is higher than the female, conforming that the female pupa require more energy in the form of less pupal weight loss for ovipositional activities. The regression equation clearly shows higher percentage loss of daily pupal weight in male than female with respect to age and, this is also evident from the slope of the regression line. Moreover, analysis of the coefficient of correlation shows that the weight loss of pupa is directly correlated with the age rather than climatic parameters under which the pupa dwells.

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Regional Comparison of Physiochemical Properties of Codonopsis lanceolata

  • Kwon, Soo Jeong;Park, Tae Yeon;Lee, Moon Soon;Boo, Hee Ock;Cho, Gag Yeon;Woo, Sun Hee;Cho, Jin Woong;Lee, Hee Doo;Cho, Seong-Woo;Kim, Hag Hyun
    • 한국작물학회지
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    • 제60권2호
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    • pp.248-252
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    • 2015
  • This study was conducted to compare the growth, inorganic components, and proximate components of Codonopsis lanceolata grown in 10 regions of Korea for selecting superior species and breeding by crossing. Among the all tested lines, the shortest plant height (217.12 cm) was observed from the Ulleungdo region line (No. 4) while the longest (273.9 cm) was observed from Hwasun region line (No. 9). In addition, the lines of central and northern region (No. 1~No. 7) tend to have shorter plant height than those of southern region (No. 8~No. 9) except Jejudo region line (No. 10). Flowering tends to be late towards southern region, and lines in central and northern regions were started flowering about 2 weeks earlier than those in southern regions. However, the heaviest root weight was 13.1 g, found in only Jejudo line (No. 10) whereas there was no significant difference found in the other regions which have a range of 8.3~11.0 g. The inorganic components were varied in each line, however, proportion of macroelements, such as K, Ca, and P, was the largest for every line. Especially for Heongseong region line (No. 2), had larger proportion of macroelements than the others. There was a difference of proximate compositions of Codonopsis lanceolata, except the moisture content, among all regions, however, it was generally shown that the content of crude protein (1.31~3.76%) and crude fiber (2.18~3.12%) was the highest.

2축 분할식 차량 구동라인의 굽힘진동 저감을 위한 동흡진기 최적설계 (Optimum Design of Dynamic Vibration Absorber for Reducing Bending Vibrations of Two-Piece Vehicle Drive Line)

  • 이상범;유영선
    • 한국음향학회지
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    • 제29권2호
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    • pp.118-124
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    • 2010
  • 본 논문에서는 차량 구동라인의 굽힘 진동을 저감시키기 위해 사용되는 동흡진기의 설계 파라미터에 대한 최적설계를 수행하였다. 정확한 동적 응답특성을 얻기 위해 구동라인을 구성하는 추진축의 진동해석으로부터 추출된 유연성 데이터를 구동라인 동역학 모델에 적용하여 유연체 구동라인을 만들었다. 동흡진기의 내부 튜브 질량, 고무 강성계수 및 고무 감쇠계수를 최적화를 위한 설계 파라미터로 선택하였다. 구동라인의 수직 가속도를 최소화시키기 위해 중심합성 실험계획법의 3-요인, 2-수준 실험을 15회 수행하여 목적함수에 대한 2차 회귀방정식을 만들었으며, 최적화 프로그램을 이용하여 동흡진기 설계 파라미터들을 결정하였다. 최적화된 동흡진기를 장착한 차량 모델은 초기 모델에 비해 구동라인의 수직 가속도 피크값을 17.1% 감소시켰다.

New Reports of One Euteliid (Lepidoptera: Euteliidae) and Two Nolid (Lepidoptera: Nolidae) Moths from Korea

  • Choi, Sei-Woong;Kim, Sung-Soo
    • Animal Systematics, Evolution and Diversity
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    • 제34권2호
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    • pp.96-100
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    • 2018
  • One species of Euteliidae, Targalla delatrix ($Guen{\acute{e}}e$) and two species of Nolidae, Nola miyanoi Sasaki and Nola semiconfusa (Inoue) are reported for the first time in Korea. Targalla delatrix can be distinguished by the dark brownish forewings that show the transverse antemedial line, the costally rounded postmedial line and the bowl shaped marking on the costal part of subtermen and the dark brownish hindwings. Nola miyanoi can be distinguished by the whitish forewings that have the band-shaped central fascia with the blackish undulating antemedial line and the dark brownish undulating postmedial line and the whitish hindwings with a light blackish discal dot. Nola semiconfusa can be distinguished by the light grayish forewings that show deeply indented antemedial line, medially strongly projected and dentate postmedial line, a dark brownish subterminal line and a dark brownish termen, and the whitish hindwings with a light grayish discal dot. Adults and genitalia are illustrated and briefly described with their biological and distributional notes.