1984년도 이후의 CH Cygni의 스펙트럼의 변화

柳桂和 梨花女子大學校 韓國生活科學硏究院 1990 韓國生活科學硏究院 論叢 Vol.46 No.-

Spectroscopic behaviors for some spectral lines like He I, Hγ, Hδ, [Fe Ⅱ] of CH Cygni are described during the year 1977-1984. We have fitted the emission and absorption components of the Hγ and Hδ profiles, and the emission component of the FeⅡ profile with a two-three Gaussian profile characterized by broad, medium and narrow components. The brood widths of the Hγ and Hδ profiles on the continuum level seem as the result of a Doppler motion of the material originated the lines of He I and H I. And the several components in Balmer lines may be due to a shock wave driven by a bipolar flow roughly perpendicular to the line of sight. We believe that the flow is the result of an evolution stage of the accretion disk.

CH Cygni의 [OⅢ]선

柳桂和 梨花女子大學校 韓國生活科學硏究院 1988 韓國生活科學硏究院 論叢 Vol.42 No.-

성운의 특징인 [OⅢ]의 스펙트럼선의 변화를 보고하였다. 이 성운선의 강도는 gf값의 증가에 따라 증가하지 않은 것 같다. 이 성운선의 Doppler속도가 FWHM 값에서 계산되었다. The developing spectral features of [OⅢ] characteristic of the nubulae are studied. It seems to show that the intensities of the lines do not increase with increasing gf values. The Doppler velocities for the nebular lines were estimated from the values of FWHM.

CH Cygni의 Balmer선

柳桂和 梨花女子大學校 韓國生活科學硏究院 1989 韓國生活科學硏究院 論叢 Vol.44 No.-

1967년, 1977년의 CH Cygni의 폭발현상 때, Balmer선의 변화에 대하여 서술했다. Balmer선의 lower members의 선폭증가는 Stark효과에는 무관하나, 작은 양이지만 난류운동에는 관계가 있는 것 같다. 선폭증가의 주원인은 강착원반에서의 물질의 Kepler운동에 의한 Doppler효과 때문으로 생각된다. 폭발현상 때의 복사는 M6Ⅲ와 어떤 black body의 복합복사를 나타낸다. The Spectral behaviours of the Balmer lines during the eruption phases in 1967, and 1977 were described. It seemed to show that the line broadening of the lower members in the Balmer lines was not due to the Stark effect, but due to the small turbulence motion in the disk. The most line broadening results from the Doppler effect brought by the Keplerian motion of the matter in the disk. The composite radiation in both MbⅢ and a black body required the radiation of the CH Cygni in these active periods.

성별 및 수준별 10학년 학생들의 과학 성취도 분석

이병국,강용희,유계화 慶北大學校 科學敎育硏究所 2004 科學敎育硏究誌 Vol.28 No.-

The purpose of this study is to examine the differences of science achievement by gender and by level of academic achievement. The subjects are consisted of 211 male and 212 female 10th graders in Daegu Metropolitan City and are also divided into three groups: low-, average-, and high-academic achievement level. All kinds of examinations which the subjects had taken during 2003 academic year were analyzed (e.g., the regular, trial, entrance diagnostic evaluation and formative examinations). The results indicate that statistically significant differences exist on the scores between male and female students. In general, the scores of female students (both low- and average-academic achievement level) are higher than male students. However, the scores for male students who had high level of academic achievement are higher than those of female students who had high level of academic achievement. Specifically, the scores of the regular examinations for female students are higher than those of male student. However, female students have no higher scores in the trial examinations than male students compared to the other examinations. This corresponds to Kimball(1989)'s hypothesis that female students are poor at the external examinations. In addition, the variation of scores is very steep in the entrance diagnostic evaluation and formative tests compared to regular and trial examinations. It seems that the achievement on tests does not determined by gender, however, the students' state of seriousness related to the tests. Additional analysis reveals that male students have made weaker achievement on scores of biology in the regular and trial examinations. Female students who had high-academic achievement level have made higher scores on the regular examination. In general, it seems that males had been more affirmative than females in the attitude related scientific subjects. However, there is no significant correlation between scientific attitude and science achievement. Based on the results of this study, there are no gender differences in the attitude for learning science. It appears that students who had high-academic achievement level are tended to have more positive attitude toward studying science.

삼부이론을 적용한 창의적 사고 배양 수업안의 개발 : 지구과학 분야를 중심으로 Especially for High School Earth Science Education

최임조,임영구,강용희,유계화 慶北大學校 科學敎育硏究所 2003 科學敎育硏究誌 Vol.27 No.-

The enrichment triad model(Renzulli, 1977) which was originally developed for teaching and learning of gifted and talented children consists of three types of enrichment activities. Type Ⅰ enrichment activities build knowledge for later use in 'gifted behaviors', and type Ⅱ enrichment activities focus on the 'how-to skills,' attitudes and values the student must develop to become and effective investigator, problem solver and producer. Type Ⅲ enrichment activities, the pursuit of real problems and realization of gifted behavior, are the fundamental goal for this model. In this study we developed enrichment activities for high school earth science class. We could summarize enrichment activities as follows: In studying the fossil section, after reporting their research activities on fossil data, students can understand the fossil theory through questioning and answering their homeworks. They can enhance their interest and curiosity by watching the movie 'Jurassic Part'(type Ⅰ enrichment activities). After making replica of fossil samples(type Ⅱ), they can write their research reports or articles concerning fossils(type Ⅲ). Students can extend their knowledge about fossils through these types of enrichment activities. In studying weather map section, after collecting newspaper clippings or searching internet, students present their knowledge about weather and weather maps(type Ⅰ enrichment activities). Learning how to make weather maps and investigating how to analyze them, student can extend their knowledge(type Ⅱ). Through these activities, students can apply their knowledge to everyday life experience(type Ⅲ). The third program is 'igneous rock' section. Students investigate the fossil formation in Korea(type Ⅰ enrichment activities). They can understand the principle of volcanic activities through experiment of volcano eruption model type Ⅱ. Through drawing pictures, writing assignment of experiment activities and playing the role play of igneous rocks, teachers can help students to acquire cause or interest to study the igneous rocks(type Ⅲ). In conclusion, within a classroom instruction teachers would be utilizing all three types of activities, moving from one to the other as class, and individual needs, demand. By selecting what students want to do and making them to produce results of their activities, we are expecting that teachers can cultivate creative thinking and enhance problem solving ability of students.

Spectroscopic Observational Study using the Medium Dispersion Spectrograph at the Bohyunsan Optical Astronomy Observatory III. Symbiotic Stars

Kye Hwa Yoo,Tae Seog Yoon,Kang-Min Kim,Jin Hyung Kim,Dong Hoon Son 한국천문학회 2002 天文學會報 Vol.27 No.2

NEBULAR SPECTRUM OF PU VUL IN 2004

Yoo, Kye-Hwa The Korean Astronomical Society 2007 Journal of The Korean Astronomical Society Vol.40 No.2

A high resolution spectrum of PU Vul obtained at Bohyunsan Astronomy Observatory on April 9, 2004 is presented. At this phase, PU Vul was an emission-line star and its continuum was very weak. Emission lines of He II, H I, [Ne IV], [N II], [O III], [Ar V ] and [Fe VII] dominated the spectrum of PU Vul. Many of them exhibited hat-top profiles with strong and multi-peaked emissions on flat-tops of their profiles. Radial velocities for these lines were measured. Origins of the spectral lines are discussed in terms of the wind and the photoionization models.

SPECTRAL FEATURES OF THE SYMBIOTIC VARIABLE STAR CH CYGNI IN 2005 - 2006

Yoo, Kye-Hwa,Yoon, Tae-Seog The Korean Astronomical Society 2009 Journal of The Korean Astronomical Society Vol.42 No.4

This article reports the spectral behavior of CH Cygni, using data obtained in October 2005 and June 2006. In these epochs, CH Cygni showed emission lines of H I, Fe II, [Fe II], [O III], [N II], [Ne III] and [S II]. Many of these lines were more enhanced since 2004. The underlying M-type spectrum was removed to get the intrinsic emission profile, and the resulting profiles were deconvoluted into several Gaussian components. Also, the radial velocities for all the lines that appeared in these spectra of CH Cygni were measured. The resultant lines were compared with each other and with those obtained in 2004; the findings are explained in terms of an accretion disk and jets.

SPECTRAL BEHAVIORS OF Hβ LINE OF CH CYGNI IN A QUIESCENT PHASE

KYE HWA YOO,KANG MIN KIM,BYUNG CHUL LEE,TAE SEOG YOON,JUNG AE LEE 한국천문학회 2004 天文學論叢 Vol.19 No.1

We analyzed the high resolution H,6 line spectra of CH Cygni obtained at the Bohyunsan Astronomical Observatory (BOAO) on April 2004. The temporal changes in the Hβ line profiles are reported. We obtained the equivalent widths of the Gaussian components. Using this we estimated the length of the gaseous nebula which emits the Hβ line and the mass loss rate from the star.

ON THE INSTABILITY OF THE COLLISION ACCRETION DISK

Yoo, Kye-Hwa The Korean Astronomical Society 1997 天文學論叢 Vol.12 No.1

The collision model of the disk, based on collisions between the particles in the disk, is summarized. The dependence of disk stability on the collision of the particles is demonstrated. The energy spectrum produced in the disk is numerically calculated. We concluded that the results are not largely different from those of the standard disk model. It implies that the collision of the particles inside the disk may be considered here.