• 제목/요약/키워드: Mass Line

검색결과 1,129건 처리시간 0.023초

MOLECULAR OUTFLOWS FROM NEWLY FORMED MASSIVE STARS

  • KIM, KEE-TAE;KIM, WON-JU;KIM, CHANG-HEE
    • 천문학회지
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    • 제48권6호
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    • pp.365-380
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    • 2015
  • We map 6 massive young stellar objects (YSOs) in the CO J=2-1 line and survey 18 massive YSOs, including the six, in the HCO+ J=1−0, SiO J=2−1, H2O 616 − 523 maser, and CH3OH 70 − 61 A+ maser lines. We detect CO bipolar outflows in all the six mapped sources. Four of them are newly discovered (07299−1651, 21306+5540, 22308+5812, 23133+6050), while 05490+2658 is mapped in the CO J=2-1 line for the first time. The detected outflows are much more massive and energetic than outflows from low-mass YSOs with masses >20 M and momenta >300 M km s−1. They have mass outflow rates (3−6)×10−4 M yr−1, which are at least one order of magnitude greater than those observed in low-mass YSOs. We detect HCO+ and SiO line emission in 18 (100%) and 4 (22%) sources, respectively. The HCO+ spectra show high-velocity wings in 11 (61%) sources. We detect H2O maser emission in 13 (72%) sources and 44 GHz CH3OH maser emission in 8 (44%) sources. Of the detected sources, 5 H2O and 6 CH3OH maser sources are new discoveries. 20081+3122 shows high-velocity (>30 km s−1) H2O maser lines. We find good correlations of the bolometric luminosity of the central (proto)star with the mechanical force, mechanical luminosity, and mass outflow rate of molecular outflow in the bolometric luminosity range of 10−1−106 L, and identified 3 intermediate- or high-mass counterparts of Class O objects.

KVN Single-Dish Maser Line Surveys of Young Stellar Objects

  • 김기태;변도영;오충식;강현우;배재한;윤소영;김원주
    • 천문학회보
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    • 제35권1호
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    • pp.58.1-58.1
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    • 2010
  • We carried out simultaneous 22GHz $H_2O$ and 44GHz $CH_3OH$ maser line surveys of about 1000 galactic YSOs using KVN 21m telescopes. The sources consist of low-mass, intermediate-mass, high-mass YSOs in different evolutionary stages. We will present the preliminary results.

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정적 보행모델에 기반을 둔 4족 보행로봇의 온라인 틸팅 제어알고리즘

  • 이순걸;조창현;홍예선
    • 한국정밀공학회지
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    • 제17권3호
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    • pp.83-91
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    • 2000
  • During static walking of a quadruped walking robot, stability of the robot depends on whether the projection of the mass center is located within the supporting area that is varying with leg motion and formed by standing legs. In this paper, force margin instead of the mass center was used to determine stability and body-tilting method was used to enhance it. On-line control of body tilting was realized with simple reaction feedback based on force margin of the static walking model of the robot instead of complicated calculation. Model reference on-line control where the model searches stable pose for predefined force margin also gave good walking performance.

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On-Line Estimation of Cell Growth from Agitation Speed in DO-Stat Culture of a Filamentous Microorganism, Agaricus blazei

  • Na, Jeong-Geol;Kim, Hyun-Han;Chang, Yong-Keun
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제10권6호
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    • pp.571-575
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    • 2005
  • A simple, but effective on-line method for estimating the mycelial cell mass concentration from agitation speed data, a most readily-available process variable, has been developed for DO-stat cultures of Agaricus blazei. The dynamic change of dissolved oxygen concentration (DOC) in the initial transient period and the change in yield were considered in the development of the estimation algorithm or estimator. Parameters in the estimation algorithm were calculated from the agitation speed data at 20% of DOC. The proposed estimator could accurately predict the cell mass concentration regardless of DOC levels in the tested range of $10{\sim}40%$, showing a good extrapolation capability.

The Black Hole Mass - Stellar Velocity Dispersion Relation of Narrow-Line Seyfert 1 Galaxies

  • 윤요셉;우종학
    • 천문학회보
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    • 제37권1호
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    • pp.47.1-47.1
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    • 2012
  • Given high accretion rates close to the Eddington limit, narrow-line Seyfert 1 galaxies (NLS1) are arguably the most important AGN subclass in investigating the origin of the black hole mass-galaxy stellar velocity dispersion ($M_{BH}-{\sigma}$) relation. Currently, it is highly debated whether NLS1s are offset from the local $M_{BH}-{\sigma}$ relation. The controversy mainly comes from the fact that the [OIII] line width has been used as a proxy for stellar velocity dispersion due to the difficulty of measuring stellar velocity dispersion in NLS1s. Using the SDSS spectra of a sample of 105 NLS1, we performed multi-component fitting analysis to separate stellar absorption lines from strong AGN [FeII] complex in order to directly measure stellar velocity dispersion. We will present the result of decomposition analysis and discuss whether NLS1s follow the same $M_{BH}-{\sigma}$ relation based on the direct measurements of stellar velocity dispersion.

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SAMI Galaxy Survey Data Release 2: Absorption-line Physics

  • 오슬희
    • 천문학회보
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    • 제43권2호
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    • pp.53.1-53.1
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    • 2018
  • We present the second data release from the SAMI Galaxy Survey. The data release contains reduced spectral cubes for 1559 galaxies, about 50% of the full survey, having a redshift range 0.004 < z < 0.113 and a large stellar mass range 7.5 < log($M_*/M_{\odot}$) < 11.6. This release also includes stellar kinematic and stellar population value-added products derived from absorption line measurements, and all emission line value-added products from Data Release One. The data are provided online through Australian Astronomical Optics' Data Central. Our poster presents stellar/gas kinematics on the metallicity-mass plane and highlight several galaxies from the SAMI Galaxy Survey that have interesting stellar and gas kinematics. For more information about data release 2, please see: https://sami-survey.org/abdr.

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공정균형기법에 의한 실증적 연구 (A Practical Study on the Line Balancing)

  • 강경식;김대식
    • 산업경영시스템학회지
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    • 제8권11호
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    • pp.17-25
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    • 1985
  • In these days the industrial management are characterized by mass production. Mass production which is not possible without the rationalization in the process of production and the efficient scale of management needs development of technical administration. The object of this study is set up on the rationalization in the process of production. And this rationalization is a means to the aim of industrial management. So as to realize the rationalization in the process of production, we should think on plan of production and the line of balancing in processes of work. The line of balancing is considered as one of very valuable administration methods. The line of balancing that controls capacities and loads so that processes of work might balance in each other makes away with happenings of idleness and stagnation during the process of work As a natural consequence it follows (1) shortening in the period of Production, (2) more efficient, (3) removing the lots of tine and matter, (4) more efficient using in elements for production. Therefore, through the labour productivity and the efficiency of the process of production increased by these effects, the line of balancing was intended to curtail the basic cost. Though the previously said line of balancing could be applied to production, it should not be said that we can completely balance in each lines of work. In other words it is impossible that the line of balancing is completely executed in every lines of work. For that reason, we should arrange the level of balancing in lines. Nowaday, in our country, it is true that the line of balancing is hardly executed at manufacturing industries. Therefore if we execute and apply the line of balancing to manufacturing industries and the larger field as well , we could curtail the basic cost, through which we could reinforce not only the international competative power but increase the labour productivity. As a result, by these effects, we would rationalize the industrial management.

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Effects of Combustor-Level High Inlet Turbulence on the Endwall Flow and Heat/Mass Transfer of a High-Turning Turbine Rotor Cascade

  • Lee, Sang-Woo;Jun, Sang-Bae;Park, Byung-Kyu;Lee, Joon-Sik
    • Journal of Mechanical Science and Technology
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    • 제18권8호
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    • pp.1435-1450
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    • 2004
  • Experimental data are presented which describe the effects of a combustor-level high free-stream turbulence on the near-wall flow structure and heat/mass transfer on the endwall of a linear high-turning turbine rotor cascade. The end wall flow structure is visualized by employing the partial- and total-coverage oil-film technique, and heat/mass transfer rate is measured by the naphthalene sublimation method. A turbulence generator is designed to provide a highly-turbulent flow which has free-stream turbulence intensity and integral length scale of 14.7% and 80mm, respectively, at the cascade entrance. The surface flow visualizations show that the high free-stream turbulence has little effect on the attachment line, but alters the separation line noticeably. Under high free-stream turbulence, the incoming near-wall flow upstream of the adjacent separation lines collides more obliquely with the suction surface. A weaker lift-up force arising from this more oblique collision results in the narrower suction-side corner vortex area in the high turbulence case. The high free-stream turbulence enhances the heat/mass transfer in the central area of the turbine passage, but only a slight augmentation is found in the end wall regions adjacent to the leading and trailing edges. Therefore, the high free-stream turbulence makes the end wall heat load more uniform. It is also observed that the heat/mass transfers along the locus of the pressure-side leg of the leading-edge horseshoe vortex and along the suction-side corner are influenced most strongly by the high free-stream turbulence. In this study, the end wall surface is classified into seven different regions based on the local heat/mass transfer distribution, and the effects of the high free-stream turbulence on the local heat/mass transfer in each region are discussed in detail.

철봉 리발코(Rybalko) 동작의 운동학적 분석 (The Kinematic Analysis of the Rybalko Motion on the Horizontal Bar)

  • 이병원
    • 한국운동역학회지
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    • 제16권1호
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    • pp.109-117
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    • 2006
  • The purpose of this study was done in order to investigate the Kinematical variables of the Rybalko motion on the Horizontal bar using the 3-dimensional cinematographic method. For this study, three excellent athletes take part in a 2003 Daegue universid game were chosen. The subject,s Rybalko motion was filmed with S-VHS camera at the speed of 60 fields per second and digitized the each fields. And the Kwon3D 3.1 version program was employed to obtain 3-dimensional data. As a result of this study. 1. A total time spent for performing Rybalko skill was Mean $2.52{\pm}0.13sec$. From starting down swing to releasing right hand the Mean $0.84{\pm}0.24sec$ was taken. 2. In the event 3 of Rybalko motion, that is, the moment which the right-hand is released on the bar, the center of mass must is employed at the position above the horizontal line of bar. In this research, the average vertical displacement(z axe) of center of mass shows $47.87{\pm}3.14cm$. 3. In the event 5, that is, the moment which the right-hand is catched again on the bar, the center of mass is employed at the position before the vertical line of bar. In this research, the average horizontal displacement(z axe) of center of mass shows $47.87{\pm}3.14cm$. 4. It has been seen that, at the moment of release of right-hand, lateral variation of center of mass is 13.395cm, vertical variation of center of mass is 7.41cm Thus, it is concluded that lateral variation of center of mass should be reduced for high grade to be acquired. 5. It has been founded that high speed of down swing influences speed of up swing, and that, in the motion of twist, the horizontal speed is little changed.

온라인 교육에 대한 사교육비 지출 실태 및 효과 분석 (A Study on the private education expenditures using on-line education and it교s effect)

  • 김성희
    • 가족자원경영과 정책
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    • 제6권1호
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    • pp.53-72
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    • 2002
  • The purpose of the research is to investigate the amount of private education expenditures for on-line education and the factors which affect on-line education expenditures and its decreasing effect of private education expenditures. The results of this study can provide basic materials to found policy to decrease private education market and private education expenditures. The sample of this study was 484 parents who had an experience using on-line education for their children being in mainly constituted by classes of pre-school over and less than high school student. The results was as follows. First, education expenditures for on-line education are 64,900won and the English and the Mathematics as main reasons using on-line education were that it is available for 24 hours and cheaper than off-line education. The parents got information for on-line education by internet, mass media and their next-door neighbors. Second, the significant variables which affect on-line education expenditures and its decreasing effect of education expenditures were the children's school level and financial related factors.

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