• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.58.3-59
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• 2018

We present the results of high resolution spectral analysis for Type Ia supernova SN 2014J in M82, which was discovered on 21 January 2014 UT. We performed spectroscopic observations for SN 2014J in its early phase at Bohyunsan Optical Astronomy Observatory with the high resolution echelle spectrograph BOES attached to 1.8-m reflector. Spectra of 26 epochs in 6 nights were obtained from 22 January 2014 to 23 February 2014 UT. Spectral feature variations for several significant lines including Si II and Ca II lines will be shown and discussed.

• Journal of Biomedical Engineering Research
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• v.11 no.2
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• pp.283-288
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• 1990

As one of the main purpose of the physical management of cleft palate is to provide for the anatomic and physiologic requisites for speech, the speech must be as one of the criteria for determining when physical management has been achieved. But there is no objective methods to evaluate the speech of cleft palate patients. The authors tried to analyze the speech of adult cleft palate patients using sound spectrog raphy and compared with normal adults. The results were obtained as follows ; 1. In Vowels, cleft palate patients of both sexes showed reduction of frequency of the first and second formant as compared to normal. There was minimal difference in front vowels (i, e, ae) 2. In consonants, cleft palate patients showed reduction of frequency of the first formant in both sexes but reduction of frequency of the second formant was noticed only in fe- male patients. 3. There was no statistical difference in sound spectrograph between plosive, fricative, africative, nasal, and glide consonants.

• Proceedings of the KSLP Conference
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• 1995.11a
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• pp.128-136
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• 1995

Diagnostic evaluation for voice disorders requires a multidimensional approach : physiological examination of the larynx and the vocal tract, aerodynamic studies, examinations of vocal fold vibrations, psychoacoustic evaluations, acoustical analyses, and so on. Previous studies with the use of a computer system suggested that the acoustic evaluation is quite promising for differentiating some causative diseases of voice disorders(Hiki et al., 1975a, b, 1976 ; Kakita et al., 1980). However, a well-equipped computer system for acoustic analysis is very expensive and not available in most voice clinics. A sound spectrograph is available in many voice clinics. (omitted)

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.19 no.2
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• pp.101-106
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• 2008

The speech signal has been put into a form suitable for storage and analysis by computer, several different operation can be performed. Filtering, sampling and quantization are the basic operation in digiting a speech signal. The waveform can be displayed, measured and even edited, and spectra can be computed using methods such as the Fast Fourier Transform (FFT), Linear predictive Coding (LPC), Cepstrum and filtering. The digitized signal also can be used to generate spectrograms. The spectrograph provide major advantages to the study of speech. So, author introduces the basic techniques for the acoustic recording, digital signal processing and the principles of spectrum and spectrogram.

• Journal of The Korean Astronomical Society
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• v.13 no.1
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• pp.1-8
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• 1980

Simultaneous observations of high resolution spectra of CaII H, K, ${\lambda}8542\;and\;{\lambda}8498$ have been made over a sunspot umbra (SPO 5007) by means of Sacramento Peak Observatory's HIRKHAD program with the Echelle spectrograph at the Vacuum Tower Telescope. The observed spectra scanned by SPO's fast microphotometer have been reduced for later theoretical interpretations. The reduced profiles, sampled over a region which is thought to be coolest over the spot, are presented in units of absolute intensity. The core intensity ratios of $I(K_3)/I(H_3);and\;I({\lambda}8498)/I({\lambda}8542)$ arc found to be 1.3 and 1.14, respectively.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.150.1-150.1
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• 2011

한국천문연구원은 미국 텍사스 대학 및 경희대와 함께 2개의 적외선 고분산 분광기 프로젝트를 진행하고 있다. 2013년 완성을 목표로 진행하고 있는 IGRINS ((the Immersion GRating INfrared Spectrograph) 는 최종 설계를 완료하여 지난 8월 25일 최종 설계 검토 회의를 진행하였으며, 내년 상반기까지 제작, 하반기 실험실 정렬을 거쳐 2013년맥도날드 2.7미터 부착 시험 관측을 예정하고 있다. 한국이 참여하고 있는 거대망원경 GMT (Giant Magellan Telescope)의 제 1세대 관측기 기로 제안한 고분산 적외선 분광기 GMTNIRS 는 IGRINS의 성능에 J, L, M band 분광기능을 더한 것이다. 총 6개의 개념 설계 기기중 하나로 선정되어 지난 1년간 개념설계를 진행해 왔으며, 10월 3일 최종 개념 설계 검토 회의를 진행할 예정이다. 이 두 기기의 성능, 현재까지의 진행상황 그리고 앞으로의 계획에 대해 설명한다.

• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.86-87
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• 2001

Far-ultraviolet IMaging Spectrograph(이하 FIMS)는 2002년에 발사 예정인 과학위성 1호의 주 탑재체이며, 은하 주변에 분포한 고온의 가스에서 방출되는 자외선 영역 (short wavelength band ： 900-1150 $\AA$, long wavelength band ： 1335-1750$\AA$)의 방출선을 약 2$\AA$의 분광 분해능으로 관측하는 천문학적 목표를 가지고 있다 일반적인 망원경을 사용하는 대신 제한된 위성의 크기 내에서, 넓은 지역에 퍼져 있는 가스의 분포와 특성을 관측하는데 적합하도록, 그림 1과 같이 비축 포물 원통 반사경과 타원형의 substrate를 가진 회절 에돌이발 (grating)의 사용을 고안하였다. (중략)

• Publications of The Korean Astronomical Society
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• v.29 no.3
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• pp.35-44
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• 2014

In ground-based astronomical spectroscopic observations, there are many telluric absorption lines that are laid on the spectra of celestial objects. To study the physical properties of the celestial objects with these contaminated spectra, the telluric lines should be removed. A conventional method for removing the telluric lines is using the standard stellar spectrum as telluric line. In this paper, we introduce a technique to calculate synthetic telluric spectra and use them to remove telluric lines from a spectrum of a celestial object. We used Line-by-Line Radiative Transfer Model (LBLRTM) for calculating a synthetic spectrum and selected Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) model as atmospheric model. We apply our method to some spectra obtained by Bohyunsan Observatory Echelle Spectrograph (BOES) to show that the telluric lines are well removed from the observed spectra by our model within an accuracy of 2% which is close to the 1-sigma rms of the original spectra.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.1
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• pp.55.2-55.2
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• 2013

We present the observational study of parsec-scale jets from YSOs reaching lengths of several arc-minutes. The medium-resolution spectroscopic data were obtained between 6000 - $7000{\AA}$ with BOAO long-slit spectrograph. By performing multi-position observation, we investigated the physical variation of the jets and the ambient gas along the whole path of the jets. The flux, electron density, ionization fraction, and electron temperature are discussed with the estimated line ratios between from [OI], [NII], $H{\alpha}$ and [SII] emission lines. This study carried out with more than 8 jets of YSOs including low- to intermediate-mass stars. We also briefly discuss the kinematics of the outflows using spatial and spectroscopic data.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.63.3-63.3
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• 2016

NYSC 1m telescope is completely assembled now, and equipped with FLI PL-16803 4k CCD and Shelyak eShel spectrograph (R~10,000) on optical system of f/8. From 12th Jan 2016, optical system alignment and test observations have been performed. We present the result of M35 photometric observation for the performance test of the 1m telescope. The photometric observation was carried out for the central part of M35 with the field of view, ${\sim}15^{\prime}.8{\times}15^{\prime}.8$. Standard transformation to the UBVI system was done by the photometric data of M35 in Sung and Bessell(1999).