• 천문학회지
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• 제52권6호
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• pp.235-244
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• 2019

We present the results of near-infrared imaging observations of the galaxy overdensity around the z = 1.44 radio-loud active galactic nucleus (AGN) 6CE1100+3505, which was carried out with the purpose of sampling the redshifted Hα emission from the actively star-forming galaxies that could constitute the overdensity. The existence of the structure around this AGN was spectroscopically confirmed by previous grism observations which are however limited to the central region. Using the CH4Off narrow/medium-band and H broad band filters in the Wide Infrared Camera (WIRCam) on the Canada-France-Hawaii Telescope (CFHT), we constructed a sample of objects that show a flux excess in the CH4Off band due to line emission. The emission line flux is ~ 4.9 × 10^-16 erg s^-1 cm^-2, corresponding to a star formation rate (SFR) of ~ 50 M_⊙ yr^-1 for galaxies at redshifts z ~ 1.4. None of the galaxies with medium-band flux excess is located within 1 Mpc from the central AGN, and there is no evidence that the selected galaxies are associated with the proposed cluster. Along with the star formation quenching near the center that was found from the previous grism observations, the lack of extreme starbursts in the structure suggests that at z ~ 1.4, overdense regions are no longer favorable locations for vigorous star formation.

• 한국수자원학회논문집
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• 제48권8호
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• pp.659-672
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• 2015

홍수시 하천의 유속 측정을 위한 표면영상유속계에서 가장 기본이 되는 단계는 적절한 영상을 취득하는 것이다. 하지만 영상 획득에 있어 야간에 발생하는 홍수 흐름을 촬영하는 것은 매우 어렵다. 이에 본 연구에서는 표면영상 유속계의 야간 영상 획득 장치로 원적외선 카메라를 이용하는 방안을 검토하였다. 원적외선 카메라는 별도의 조명을 필요로 하지 않으므로, 주야간 모두 영상을 획득할 수 있는 장점이 있다. 또한 안개나 연기의 영향을 받지 않아서 고정식 표면영상유속계를 구성하는 좋은 대안이 될 수 있다. 원적외선 영상을 이용한 유속 산정의 결과를 비교하기 위해, 보통의 가시광 카메라와 근적외선 카메라를 이용한 동시 촬영을 하여 영상을 분석하였다. 아울러 소형 프로펠러 유속계에 의한 유속 측정 자료와 비교하였다. 정확도 분석 결과 원적외선의 주간 영상을 이용할 경우 최소-9%에서 최대 -19%의 오차를 나타냈고, 야간 영상을 이용할 경우 최소 -10%에서 최대 -23%의 오차를 나타냈다. 또한 일반캠코더를 이용한 경우와 비교하여 최대 10% 이내의 차이를 보였기 때문에 주야간 유속 측정에 원적외선 카메라의 적용이 가능한 것을 확인하였다. 다만 주간 영상에 비해 야간 영상이 약간 흐려지는 경향이 있기 때문에, 이러한 영상을 적절히 분석하기 위한 지속적인 연구가 필요할 것으로 생각한다.

• Journal of Astronomy and Space Sciences
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• 제20권3호
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• pp.217-226
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• 2003

MSC (Multi-Spectral Camera) is the payload of KOMPSAT-2, which is being developed for earth imaging in optical and near-infrared region. The design of the MSC is completed and its reliability has been assessed from part level to the MSC system level. The reliability was analyzed in worst case and the analysis results showed that the value complies the required value of 0.9. In this paper, a calculation method of reliability for the MSC system is described, and assessment result is presented and discussed.

• 천문학회보
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• 제37권1호
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• pp.51.2-51.2
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• 2012

Red Active Galactic Nuclei (AGNs) are suspected to intermediate stage between ULIRG and AGN phase. As well as, red AGNs are suspected to have more than 50% of whole AGN population. For understanding the characteristics of red AGN, Black Hole (BH) mass is a key property and can not be estimated by existed method such as reverberation mapping and single epoch method using 5100A continuum and Balmer lines. Thus we still don't know their characteristics and properties in clearly. To estimate properties of red AGNs without the effect of dust extinction, we obtained Near InfraRed (NIR) spectra of 31 reverberation mapped AGNs and 49 Palomar-Green(PG) Quasi-Stellar Objects (QSOs) by using the infrared camera (IRC) of AKARI space telescope with unique wavelength range 2.5-5.0 ${\mu}m$. Upon this spectra, we measured the FWHM and luminosity of Brackett ${\alpha}$ and ${\beta}$ lines for deriving new BH mass estimators of AGNs.

• 천문학회보
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• 제35권2호
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• pp.32.2-32.2
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• 2010

Red dusty Active Galactic Nuclei (AGNs) are suspected to mid-stage between ULIRG and AGN phase. As well as, they are suspected that they have more than 50% of AGN population. To understand character of red AGN, Black Hole (BH) mass of red AGN is a key property and haven't measured by existing method such as reverberation mapping and single epoch method. So we still don't know their character and properties clearly. To estimate properties of red AGNs escape from effect of dust-obscuration, we have obtained Near InfraRed (NIR) spectra of 31 reverberation mapped AGNs and 49 Palomar-Green(PG) Quasi-Stellar Object (QSO) using the infrared camera (IRC) for AKARI with unique wavelength range 2.5-$5.0{\mu}m$. From this spectra, we measured the FWHM and luminosity of brackett ${\alpha}$, ${\beta}$ at 4.0, 2.6 micron meter for deriving new BH mass estimators based on the properties of Brackett line emission.

• 천문학회보
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• 제36권2호
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• pp.149.1-149.1
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• 2011

보현산 천문대의 근적외선 카메라시스템인 KASINICS(KASI Near Infrared Camera System)를 사용하여 다주기 변광성 BL Cam을 관측하였다. BL Cam(${\alpha}=03^h47^m19^s$, ${\delta}=+63^{\circ}22'7"$[J2000.0], V=13.10, ${\Delta}V$=0.33mag)은 광학적 쌍성으로 SX Pheoenics 변광성 중 하나이며 0.03 - 0.08day의 짧은 주기를 갖는 다주기 변광성으로 알려져 있다. 대상 천체의 적외선 관측을 위하여 한국천문연구원에서 개발한 지상 망원경용 근적외선 카메라 시스템 KASINICS를 사용해 J, H, Ks filter로 시계열 관측을 하였다. 대상 천체의 가시광 파장대에서의 관측 자료와 적외선 파장대에서의 관측 자료를 비교 분석함으로써 천체의 외곽층에서 발생하는 상호작용에 대해 알아볼 수 있다.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2004년도 한국우주과학회보 제13권2호
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• pp.70-70
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• 2004

• 천문학회보
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• 제36권1호
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• pp.51.1-51.1
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• 2011

Red dusty Active Galactic Nuclei (AGNs) are suspected to mid-stage between ULIRG and AGN phase. As well as, red AGNs are suspected that they have more than 50% of whole AGN population. In order to understand the character of red AGNs, Black Hole (BH) mass of red AGN is a key property and can not measured by existing method such as reverberation mapping and single epoch method. Thus we still don't know their character and properties in clearly. To estimate properties of red AGNs without the effect of dust-obscuration, we have obtained Near InfraRed (NIR) spectra of 31 reverberation mapped AGNs and 49 Palomar-Green(PG) Quasi-Stellar Object (QSO) by using the infrared camera (IRC) for AKARI with unique wavelength range $2.5-5.0{\mu}m$. From this spectra, we measured the FWHM and luminosity of brackett ${\alpha}$ and ${\beta}$ at 4.0, 2.6 micron meter for deriving new BH mass estimators based on the properties of Brackett line emission.

• 천문학회보
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• 제39권2호
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• pp.92.1-92.1
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• 2014

In astronomical spectroscopy, stable auto-guiding and accurate target centering capabilities are critical to increase the achievement of high observation efficiency and sensitivity. We developed an instrument control software for the Immersion GRating INfrared Spectrograph (IGRINS), a high spectral resolution near-infrared slit spectrograph with (R=40,000). IGRINS is currently installed on the McDonald 2.7 m telescope in Texas, USA. We had successful commissioning observations in March, May, and July of 2014. The role of the IGRINS slit-viewing camera (SVC) is to move the target onto the slit, and to provide feedback about the tracking offsets for the auto-guiding. For a point source, we guide the telescope with the target on the slit. While for an extended source, we use another a guide star in the field offset from the slit. Since the slit blocks the center of the point spread function, it is challenging to fit the Gaussian function to guide and center the target on slit. We developed several center finding algorithms, e.g., 2D-Gaussian Fitting, 1D-Gaussian Fitting, and Center Balancing methods. In this presentation, we show the results of auto-guiding performances with these algorithms.

• 한국운동역학회지
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• 제24권3호
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• pp.189-199
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• 2014

The purpose of this study was to compare pflugbogen's biomechanical characteristics between on the ski simulator and snowed ski slope to develop interactive ski simulator. Nine ski instructors(sex: male, age: $29.6{\pm}5.4yrs$, height: $176.0{\pm}5.6cm$, body mass: $76.0{\pm}14.0kg$) belong to Korean Ski Instructors Association participated in this research. 24 Infrared cameras for snowed ski slope experiment and 13 infrared camera for ski simulator experiment were installed near by path of pflugbogen. The participants did pflugbogen on the snowed ski slope and the ski simulator both. During the experiment, the participants weared motion capture suit with infrared reflective makers on it, and plantar pressure sensors in ski boots, so that ski motion and plantar pressure data were collected together. Displacement of COG(center of gravity) movements, trunk flexion/extension angle, adduction/abduction angle, and plantar pressure data were significantly different between on the simulator and ski slope. However, percentage of time of COG movement in the phases during medial/lateral and anterior/posterior movement were not significantly different. Findings indicate that the difference between two groups occurred because the ski simulator's drive mechanism is different from ski motion on the slope. In order to develop the ski simulator more interactively for pflugbogen, the ski simulator's drive mechanism need to be reflected 3D motion data of pflugbogen on the slope that were purposed in this research.