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A Comparison Study on the Effect Size According to the Type of Fandom Activities : Based on Meta-analysis (팬덤활동의 유형에 따른 효과크기 비교 연구: 메타분석 기반)

  • Kim, Jhong-Yun;Kim, Eun-Bee
    • Journal of the Korea Convergence Society
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    • v.11 no.6
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    • pp.259-268
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    • 2020
  • The purpose of our study is to conduct a general·quantitative analysis of fandom activities and verify their organization types and effects. The results are as follows. With regard to the comparison of effect size, the variable related to the social and economic field showed the greatest effect size, which was followed by individual behavior and individual mentality. In terms of influential factors of fandom activities, the effect size of positive variables was intermediate level while the effect size of negative variables was low level. In addition, the effect size of fandom supporting idol groups was the greatest, which was followed by of fandoms supporting sports stars, and actors. In terms of the effect size with regard to the influence on fandom among the objects of study, the effect size of university students was the greatest, which was followed by the whole, adult, middle and high school student, and middle school student. Meanwhile, the result of the analysis according to the classification by country showed that China had the greatest effect size, and the US also showed quite a big effect size. On the other hand, South Korea showed a low level of effect size.

Systemic search for gas outflows in AGNs and star-forming galaxies

  • Woo, Jong-Hak;Son, Donghoon;Bae, Hyun-Jin
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.35.2-35.2
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    • 2016
  • We present a census of AGN-driven gas outflows based on the kinematics of ionized gas and stars, using a large sample of ~11,000 emission line galaxies at z < 0.3, selected from SDSS. First, a broad correlation between gas and stellar velocity dispersions indicates that the bulge gravitational potential plays a main role in determining the ionized gas kinematics. However, the velocity dispersion of the [OIII] emission line is larger than stellar velocity dispersion by a factor of 1.3-1.4, suggesting that the non-gravitational (non-virial) component, i.e., outflows, is almost comparable to the gravitational component. Second, gas-to-stellar velocity dispersion ratio increases with both AGN luminosity and Eddington ratio, suggesting that non-gravitational kinematics are clearly linked to AGN accretion. The distribution in the [OIII] velocity - velocity dispersion diagram dramatically expands toward large values with increasing AGN luminosity, implying that the launching velocity of gas outflows increases with AGN luminosity. Third, the fraction of AGNs with a signature of the non-gravitational kinematics, steeply increases with AGN luminosity and Eddington ratio, while the majority of luminous AGNs presents the non-gravitational kinematics in the [OIII] profile. These results suggest that ionized gas outflows are prevalent among type 2 AGNs. On the other hand, we find no strong trend of the [OIII] kinematics with radio luminosity, once we remove the effect of the bulge gravitational potential, indicating that ionized gas outflows are not directly related to radio activity for the majority of type 2 AGNs. We will discuss the implication of these results for AGN feedback in the local universe.

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Impact of Science Club Activities Associated with STEAM Activities on Students' Self-Efficacy and Attitudes toward Science (과학 동아리 활동과 연계된 STEAM 활동이 학생들의 자기효능감과 과학에 대한 태도에 미치는 영향)

  • Jung, Ji-ye;Wee, Soo-meen;Lim, Sung-man
    • Journal of the Korean Society of Earth Science Education
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    • v.8 no.2
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    • pp.183-192
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    • 2015
  • The purpose of this study was to identify STEAM education program fit for club activities in consideration of the present curriculum and investigate its effect on science club students' self-efficacy and attitude toward science by applying it to science club students. In consideration of such chapters as 'Solar System' and 'Exosphere and Space Development' in the 2009 Revised Curriculum, this study developed a STEAM education program related to the observation of the solar system and the measurement of a distance of the stars in consideration of the present curriculum. For this study we selected 14 science club students in H Middle School, located in G Province and applied a 7 weeks' program to them. To find out change in their self-efficacy and attitude toward science, this study conducted tests of self-efficacy and attitude toward science for a single group before and after introducing this program and analyzed the results. The results of this study could be summarized as below. Firstly, science club activities with this STEAM education program applied improved students' self-efficacy significantly. Secondly, there was a significant difference found in students' attitude toward science through science club activities with this STEAM education program applied as they showed higher scores in the attitude toward science in the posttest than the pretest. Lastly, despite a research limit that this science inquiry program was conducted for a short period of time, this program was found to have positive effect on the improvement of students' self-efficacy and attitude toward science.

ASSOCIATION OF INFRARED DARK CLOUD CORES WITH YSOS: STARLESS OR STARRED IRDC CORES

  • Kim, Gwan-Jeong;Lee, Chang-Won;Kim, Jong-Soo;Lee, Youn-Gung;Ballesteros-Paredes, Javier;Myers, Philip C.;Kurtz, S.
    • Journal of The Korean Astronomical Society
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    • v.43 no.1
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    • pp.9-23
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    • 2010
  • In this paper we examined the association of Infrared Dark Cloud (IRDC) cores with YSOs and the geometric properties of the IRDC cores. For this study a total of 13,650 IRDC cores were collected mainly from the catalogs of the IRDC cores published from other studies and partially from our catalog of IRDC cores containing new 789 IRDC core candidates. The YSO candidates were searched for using the GLIMPSE, MSX, and IRAS point sources by the shape of their SED or using activity of water or methanol maser. The association of the IRDC cores with these YSOs was checked by their line-of-sight coincidence within the dimension of the IRDC core. This work found that a total of 4,110 IRDC cores have YSO candidates while 9,540 IRDC cores have no indication of the existence of YSOs. Considering the 12,200 IRDC cores within the GLIMPSE survey region for which the YSO candidates were determined with better sensitivity, we found that 4,098 IRDC cores (34%) have at least one YSO candidate and 1,072 cores among them seem to have embedded YSOs, while the rest 8,102 (66%) have no YSO candidate. Therefore, the ratio of [N(IRDC core with protostars)]/[N(IRDC core without YSO)] for 12,200 IRDC cores is about 0.13. Taking into account this ratio and typical lifetime of high-mass embedded YSOs, we suggest that the IRDC cores would spend about $10^4\sim10^5$ years to form high-mass stars. However, we should note that the GLIMPSE point sources have a minimum detectable luminosity of about $1.2 L_{\odot}$ at a typical IRDC core's distance of ~4 kpc. Therefore, the ratio given here should be a 100ver limit and the estimated lifetime of starless IRDC cores can be an upper limit. The physical parameters of the IRDC cores somewhat vary depending on how many YSO candidates the IRDC cores contain. The IRDC cores with more YSOs tend to be larger, more elongated, and have better darkness contrast than the IRDC cores with fewer or no YSOs.

Analysis of Contents of Reorganization of Textbooks by Pre-Service Teachers' on 'Comparison of Distances from Solar System to Planets' in First Semester of Elementary Science 5th Grade (초등과학 5학년 1학기 '태양에서 행성까지 거리 비교'에 대한 초등예비교사들의 교재 재구성 내용 분석)

  • Kim, Hae-Ran;Lee, Yong-Seob
    • Journal of the Korean Society of Earth Science Education
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    • v.14 no.3
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    • pp.225-235
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    • 2021
  • The purpose of this study is to obtain implications for the improvement direction of astronomical education methods and development of educational materials or software. In connection with the 5th grade 1st semester elementary science 'Solar System and Stars' unit, elementary pre-service teachers were given a reorganization task to compare the relative distances from the sun to the planets, and then this was analyzed. Pre-service teachers are 11 male and 19 female students in the second year of the music education department at the elementary school teacher training university in B city. The implications of the study results are as follows. First, the 'distance comparison activity using a roll of tissue paper' is suitable for simply comparing the distances from the sun to the planet, but it has limitations in allowing students to experience the vastness of the solar system or inducing student participation-centered classes. Second, it is necessary to develop software materials for elementary school students that can simultaneously reflect the size of the planet and the distance to the planet that can be applied indoors, and also experience the vastness of the solar system, as well as a wide learning space. Third, textbook materials for students have an important influence on the class design of pre-service teachers.

Development and Application of an After-school Program for an Astronomy Observation Club in a Highschool: Standardized Coefficient Decision Program in Consideration of the Observation Site's Environment (고등학교 천체 관측 동아리를 위한 방과 후 학교 프로그램 개발 및 적용: 관측지 주변 환경을 고려한 표준화 계수 결정 프로그램)

  • Kim, Seung-Hwan;Lee, Hyo-Nyong;Lee, Hyun-Dong;Jeong, Jae-Hwa
    • Journal of the Korean earth science society
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    • v.29 no.6
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    • pp.495-505
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    • 2008
  • The main purposes of this study are to: (1) to develop astronomy observation program based on a standardized coefficient decision program; and (2) to apply the developed program to after-school or club activities. As a first step, we analyzed activities related to astronomy in the authorized textbooks that are currently adopted in high schools. based on the analysis, we developed an astronomy observation program according to the standardized coefficient decision program, and the program was applied to students' astronomical observations as part of the club activities. Specifically, this program used a 102 mm refracting telescope and digital camera. we took into account the observation site's environment of the urban areas in which many school were located and then developed a the computer program for observation activities. The results of this study are as follows. First, the current astronomical education in schools was based off of the textbooks. Specifically, it was mostly about analyzing the materials and making simulated experiments. Second, most schools participated in this study were located in urban areas where students had more difficulty in observation than in rural areas. Third, an exemplary method was investigated in order to make an astronomical observation efficiently in urban areas with the existing devices. In addition, the standardized coefficient decision program was developed to standardize the magnitude of stars according to the observed value. Finally, based on the students' observations, we found that there was no difference between the magnitude of a star in urban sites and in rural sites. The current astronomical education in schools lacks an activity of practical experiments, and many schools have not good observational sites because they are located in urban areas. However, use of this program makes it possible to collect significant data after a series of standardized corrections. In conclusion, this program not only helps schools to create an active astronomy observation activity in fields, but also promotes students to be more interested in astronomical observation through a series of field-based activities.