• 천문학회지
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• 제37권4호
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• pp.211-216
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• 2004

We present the results of an H I aperture synthesis mosaic of the Large Magellanic Cloud (LMC), made by combining data from 1344 separate pointing centers using the Australia Telescope Compact' Array (ATCA) and the Parkes multibeam receiver. The resolution of the mosaiced images is 50" (<15 pc, using a distance to the LMC of 55kpc). This mosaic, with a spatial resolution .15 times higher than that which had been previously obtained, emphasises the turbulent and fractal structure of the ISM on the small scale, resulting from the dynamical feedback of the star formation processes with the ISM. We also have done a widefield panoramic survey of H$\alpha$ emission from the Magellanic Clouds with an imager mounted on the 16-inch telescope at Siding Spring Observatory. This survey produced H$\alpha$ images which are equal to the ATCA survey in area coverage and resolution. This survey allows us to produce a continuum-subtracted image of the entire LMC. In contrast with its appearance in the H$\alpha$ image, the LMC is remarkably symmetric in H I on the largest scales, with the bulk of the H I residing in a disk of diameter 8. $^{\circ}4$ (7.3 kpc) and a spiral structure is clearly seen. The structure of the neutral atomic ISM in the LMC is dominated by H I filaments combined with numerous shells and holes.

• 천문학논총
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• 제30권2호
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• pp.103-105
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• 2015

The 22 m diameter Mopra telescope in Australia is being used to undertake an improved survey of the CO J = 1-0 line at 3mm along the 4th quadrant of the Galaxy, achieving an order of magnitude better spatial and spectral resolution (i.e. 0.6 and 0.1 km/s) than the Dame et al. (2001) survey that is publically available for the Southern Galactic plane. Furthermore, the Mopra CO survey includes the four principal isotopologues of the CO molecule (i.e. $^{12}CO$, $^{13}CO$, $C^{18}O$ and $C^{17}O$). The survey makes use of an 8 GHz-wide spectrometer and a fast mode of on-the-fly mapping developed for the Mopra telescope, where the cycle time has been reduced to just 1/4 of a second. 38 square degrees of the Galaxy, from $l=306-344^{\circ}$, $b=0{\pm}5^{\circ}$ have currently been surveyed, together with additional 9 sq. deg. regions around the Carina complex and the Central Molecular Zone. We present new results from the survey (see also Burton et al., 2013, 2014). The Mopra CO data are being made publically available as they are published; for the latest release see the project website at www.phys.unsw.edu.au/mopraco.

• 천문학회지
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• 제34권3호
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• pp.167-179
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• 2001

A molecular line survey towards the UC H II region G34.3+0.15 from 155.3 to 165.3GHz has been conducted with the TRAO 14-m radio telescope. Combined with our previous observations from 84.7 to 115.6GHz and 123.5 to 155.3GHz (Paper I), the spectral coverage of this survey in G34.3+0.15 now runs from 85 to 165 GHz. From these latest observations, a total of 18 lines from 6 species were detected. These include four new lines corresponding to ${\Delta}$J = 0, ${\Delta}$K = 1 transitions of the $CH_3OH$ E-type species, and two new lines corresponding to transitions from $SO_2$ and $HC_3N$. These 6 new lines are $CH_3OH$[1(1) - 1(0)E], $CH_3OH$[2(1) - 2(0)E], $CH_3OH$[3(1) - 3(0)E], $CH_3OH$[4(1) - 4(0)E], $SO_2$[14(1, 13) -14(0, 14)] and $HC_3N$[18 -17]. We applied a rotation diagram analysis to derive rotation temperatures and column densities from the methanol transitions detected, and combined with NRAO 12-m data from Slysh et al. 1999. Applying a two-component fit, we find a cold component with temperature 13-16K and column density $3.3-3.4 {\times} 10^{14} cm^{-2}$, and a hot component with temperature 64 - 83K and column density $9.3{\times}10^{14} - 9.7 {\times} 10^{14} cm^{-2}$. On the other hand, applying just a one-component fit yields temperatures in the 47 -62 K range and column densities from $7.5-1.1 {\times} 10^{15} cm^{-2}$.

• 천문학회지
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• 제40권4호
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• pp.133-135
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• 2007

A survey project of TRAO with the fifteen beam array receiver system is presented. A multibeam array receiver system has been purchased from FCRAO, and is being installed on TRAO 14m telescope. The target region of the survey is from ${\iota}=120^{\circ}{\sim}137^{\circ},\;b=-1^{\circ}{\sim}+ 1^{\circ}$, and velocity resolution would be 1 km/sec after smoothing from the original resolution of $0.64km\;s^{-1}$ in the transition of J = 1-0 of $^{13}CO$. The survey region is a part of the $^{12}CO$ Outer Galaxy Survey(OGS), and would be an extension of the Bell Laboratories $^{13}CO$ Galactic Plane Survey. By combining with the existing $^{12}CO$ database of the Outer Galaxy Survey, we will derive physical properties of identified molecular clouds and will conduct and statistical analysis of the Outer Galalxy molecular clouds. Reduction process and analysis methods will be introduced.

• 천문학회지
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• 제35권4호
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• pp.187-196
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• 2002

A spectral line survey is performed from 159.7 to 164.7 GHz toward Orion-KL, as an extension of our previous line survey from 138.3 to 150.7 GHz with the same 14 m radio telescope of Taeduk Radio Astronomy Observatory. Typical system temperatures were 260 - 1000 K to achieve a sensitivity of about 0.02 - 0.04 K in TA unit. A total of 63 line spectra are detected in this survey. Among them, 54 lines lines are found to be the first detections towards an astronomical source and only 9 spectral lines have been previously identified from other observations. Forty-eight of 54 lines are believed to be from the known transitions of the known molecules, while 6 lines are 'unidentified'. All detected lines are found to be from a total of 10 molecular species and their isotopic variants. The molecular species with most numerous detected transitions are $HCOOCH_3$ (22), followed by $CH_3OCH_3$ (7), $C_2H_5CN$ (7), and $SO_2$ (6). The LTE rotation diagram analysis using all homogeneous data with those from previous survey gives more reliable determination of physical quantities. The derived values of the rotation temperatures and column densities for $HCOOCH_3$, $CH_3OCH_3$, and $SO_2$ are are 75 $\~$ 197 K and $1.5 {\~}18 {\times} 10^{15}\;cm^{-2}$, respectively.

• 천문학논총
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• 제27권4호
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• pp.231-234
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• 2012

We present preliminary results of supernova remnants (SNRs) in the Large Magellanic Cloud (LMC) seen by AKARI as well as Spitzer. By examining the AKARI LMC survey and the Spitzer data, we have searched for IR counterparts to 45 known SNRs in the LMC and could identify 28 SNRs with associated IR emission. 13 SNRs among them are newly detected in IR bands. For the entire IR SNRs, we make a catalog containing general information and the AKARI and/or Spitzer fluxes. Using the catalog, their IR colors and the possible correlation of the IR fluxes with the X-ray fluxes are examined. For some interesting SNRs, we have performed NIR spectroscopy with AKARI. An aromatic feature at $3.3{\mu}m$ can be identified in LMC SNR N49. We investigate the characteristics of the IR features and discuss the PAH mission mechanism in SNRs.

• 한국항만경제학회지
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• 제32권1호
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• pp.179-192
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• 2016

본 연구는 안전관리가 연안해운기업경영에 미치는 영향을 파악하기 위해 기존의 연구들과 구조화모형의 이론적 고찰을 통해 문제점을 정립하고 연구의 방향을 설정하였다. 연안해운기업의 경영에 영향을 미치는 안전관리의 요인을 추출하고 요인간의 중요도 및 우선순위를 파악할 수 있는 분석방법인 ISM을 이용하여 안전관리 구성요소들의 계층을 분석하였다. 본 논문은 지속가능한 경영을 위한 안전관리의 고도화에 필요한 요소들 간의 관계 및 구조를 파악한 기초적인 연구로서 향후 안전관리 정책에 활용할 수 있을 것으로 기대된다.

• 천문학논총
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• 제27권4호
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• pp.235-236
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• 2012

We carry out a systematic study of Galactic supernova remnants (SNRs) using the AKARI Far Infrared Surveyor (FIS) survey data. The AKARI Infrared Astronomical Satellite observed the whole sky using the four FIS bands covering 50 to 180 microns with ~1 arcmin resolution. The all-sky coverage with high-spatial resolution provides an unprecedented opportunity to study diffuse, extended far-infrared (FIR) sources such as SNRs. We have searched for FIR counterparts to all 274 known Galactic SNRs, and investigate their FIR properties of identified SNRs. We report preliminary results of the study.

• 천문학회지
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• 제29권spc1호
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• pp.193-194
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• 1996

A large scale $^{13}CO$(J=1-0) survey was made for CMa OB1/R1 region in $220^{\circ}{\le}{\iota}{\le}230^{\circ}$ and $-10^{\circ}{\le}b{\le}10^{\circ}$ with a 8' spacing by using the 4 m radio telescope of Nagoya University. 34 isolated clouds were identified in this survey. Among them, two clouds were firstly identified by us. The observed LSR velocity indicate that almost of the all clouds are located in the Local arm, except two extreme velocity. The mass spectrum of the clouds in the Local arm is best fitted by a power-law index of 1.6.

• 한국건축시공학회지
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• 제22권4호
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• pp.403-414
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• 2022

공공 시설물에 대한 자산관리는 그 중요성이 날로 증가하고 있으며 이를 위한 연구들이 다수 수행되고 있다. 본 연구는 공공자산관리의 실질적인 운영을 위한 전략 제시를 위한 기초연구로서 공공자산관리를 위한 비용 항목들간의 중요도 및 영향 관계를 비교 분석하여 비용적 관점에서 효율적인 관리 및 활용방안을 제안하고자 한다. 본 연구에서는 기존 연구를 바탕으로 비용 요인을 도출하여 상위 항목 4가지 하위 항목 19가지를 선정하였다. 이를 바탕으로 설문조사를 실시하였으며, 설문조사의 결과는 계층분석적의사결정 방법(AHP) 및 ISM(Interpretive Structural Modeling) 방법을 활용하여 분석하였다. AHP 분석법은 항목간의 우선 순위를 도출에 활용되었고, ISM은 주요 그룹 및 상호 영향도 확인에 이용되었다. 그 결과 우선 순위와 중요도 모두 높게 나타난 항목인 사용자비용, 해체·폐기비용, 대체 비용, 유지관리·보수비용 등과 같은 항목들은 공공시설물 공공자산관리에 있어서 우선적으로 고려해야할 항목으로 판단되며, 초기공사비용, 계획설계비용, 공사비용, 감리비용들은 다른 항목들에게 받는 영향은 적으나 다른 항목들에 미치는 영향은 크게 나타나므로 위 항목들 또한 공공시설물 공공자산관리 활용방안에 있어서 다른 항목들에 미치는 영향을 최소화하는 것이 필요함을 알 수 있었다. 본 연구에서 제시된 결과 및 분석 방법은 향후 공공시설물 자산관리를 위한 전략 제시에 활용될 것으로 기대된다.