• Journal of The Korean Association For Science Education
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• v.44 no.4
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• pp.301-311
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• 2024

We developed a small-group training program for in-service teachers focused on scientific modeling. We collected the discourses of the teachers who participated in the activity and analyzed them by type. The training program employed a collaborative approach in which a small group completed tasks and produced outputs based on the theme of 'galaxies and the Universe' to enable practical application in classes. Three in-service science teachers participated in the training program. Their discourses were recorded, transcribed, and classified into types based on individual turns and interaction units. The language expressions of the teachers reflected the unique characteristics of the teaching profession, with each participant having preferred language expression types, albeit with a generally low prevalence of specific language expression types across the participants. Differences in discourse characteristics related to the modeling theme, task presentation method, and model types, revealed that variations in the proportion of interaction unit types during the modeling design, build, and evaluation stages were primarily influenced by the teachers' familiarity with the modeling theme. While the task presentation method also influenced interaction types, model types had little impact on the distribution of interaction types. Considering these findings, training programs on modeling for in-service teachers should include a checklist to encourage sufficient interaction between participants as well as propose proper questions that can be effectively addressed through collaboration.

• Publications of The Korean Astronomical Society
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• v.27 no.4
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• pp.209-212
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• 2012

We present the results of the near-infrared (NIR) to mid-infrared (MIR) slit spectroscopic observations of the diffuse emission toward nine positions in the nearby irregular galaxy Large Magellanic Cloud (LMC) with the Infrared Camera (IRC) on board AKARI. The unique characteristic of AKARI/IRC provides a great opportunity to analyze variations in the unidentified infrared (UIR) bands based on continuous spectra from 2.5 to $13.4{\mu}m$ of the same slit area. The observed variation of $I_{3.3}/I_{11.3}$ suggests destruction of small-sized UIR band carriers, polycyclic aromatic hydrocarbons (PAHs) in harsh environments. This result demonstrates that the UIR $3.3{\mu}m$ band provides us powerful information on the excitation conditions and/or the size distribution of PAHs, which is of importance for understanding the evolutionary process of hydrocarbon grains in the Universe. It also suggests a new diagnostic diagram of two band ratios, such as $I_{3.3}/I_{11.3}$ versus $I_{7.7}/I_{11.3}$, for the interstellar radiation conditions. We discuss on the applicability of the diagnostic diagram to other astronomical objects, comparing the LMC results with those observed in other galaxies such as NGC 6946, NGC 1313, and M51.

• Archives of design research
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• v.19 no.5 s.67
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• pp.151-160
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• 2006

When it comes to the paintings in Joseon Dynasty, landscape and a genre paintings were popular but it was Minhwa that people of every dass loved. Minhwa contained not only true meaning of a picture, but also it was simple and straighforwardly depicted. Among them, paintings in books belonging to the Joseon Dynasty (hereinafter called Checkgeori paintings) describe a small universe in which people live harmoniously in nature on the basis of a Confucian society. In addition, it shows modern philosophy in paintings and makes a feature of human life. In this paper, 'Ssangpok Checkgeori 'in Checkgeori paintings illustrates the relationships between things such as color, arrangement, place and direction. They have outstanding features such as the direction of things in composition, multiple vanishing points, a folding screen constituent and movement of viewpoints. Therefore, we come to know the painting method of 'Ssangpok Checkgeori' can be applied to modern paintings.

• Journal of The Korean Astronomical Society
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• v.48 no.3
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• pp.195-202
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• 2015

Star forming galaxies found in the early universe exhibit asymmetric Lyα emission line that results from multiple scattering in a neutral thick medium surrounding the Lyα emission source. It is expected that emergent Lyα will be significantly polarized through a large number of resonance scattering events followed by a number of successive wing scatterings. In this study we adopt a Monte Carlo method to calculate the polarization of Lyα transferred in a very thick static slab of H_I. Resonantly scattered radiation associated with transitions between is only weakly polarized and therefore linear polarization of the emergent Lyα is mainly dependent on the number of off-resonant wing scattering events. The number of wing scattering events just before escape from the slab is determined by the product of the Doppler parameter a and the line center optical depth τ₀, which, in turn, determines the behavior of the linear polarization of Lyα. This result is analogous to the study of polarized radiative transfer of Thomson scattered photons in an electron slab, where the emergent photons are polarized in the direction perpendicular to the slab when the scattering optical depth is small and polarized in the parallel direction when the slab is optically thick. Our simulated spectropolarimetry of Lyα shows that the line center is negligibly polarized, the near wing parts polarized in the direction parallel to the slab and the far wing parts are polarized in the direction perpendicular to the slab. We emphasize that the flip of polarization direction in the wing parts of Lyα naturally reflects the diffusive nature of the Lyα transfer process in thick neutral media.

• Journal of The Korean Astronomical Society
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• v.48 no.1
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• pp.83-92
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• 2015

Recent large scale surveys such as Sloan Digital Sky Survey have produced homogeneous samples of multiple-image gravitationally lensed quasars with well-defined selection effects. Statistical analysis on these can yield independent constraints on cosmological parameters. Here we use the image separation statistics of lensed quasars from Sloan Digital Sky Survey Quasar Lens Search (SQLS) to derive constraints on cosmological parameters. Our analysis does not require knowledge of the magnification bias, which can only be estimated from the detailed knowledge on the quasar luminosity function at all redshifts, and includes the consideration for the bias against small image separation quasars due to selection against faint lens galaxy in the follow-up observations for confirmation. We first use the mean image separation of the lensed quasars as a function of redshift to find that cosmological models with extreme curvature are inconsistent with observed lensed quasars. We then apply the maximum likelihood test to the statistical sample of 16 lensed quasars that have both measured redshift and magnitude of lens galaxy. The likelihood incorporates the probability that the observed image separation is realized given the luminosity of the lens galaxy in the same manner as Im et al. (1997). We find that the 95% confidence range for the cosmological constant (i.e., the vacuum energy density) is $0.72{\leq}{\Omega}_{\Lambda}{\leq}1.0$ for a flat universe. We also find that the equation of state parameter can be consistent with -1 as long as the matter density ${\Omega}_m{\leq}0.4$ (95% confidence range). We conclude that the image separation statistics incorporating the brightness of lens galaxies can provide robust constraints on the cosmological parameters.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.58.1-58.1
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• 2017

The NISS (Near-infrared Imaging Spectrometer for Star formation history) is the near-infrared spectro-photometric instrument optimized to the first Next Generation of small satellite (NEXTSat-1). The off-axis optics was developed to cover a wide field of view with 2 deg. ${\times}$ 2 deg. as well as a wide wavelength range from 0.95 to $2.5{\mu}m$. Considering the simple alignment scheme, afocal system was adapted in the optical components. The mechanical structures were tested under the space environment. We have obtained the accurate calibration data using our test facilities under the operational condition. After the final integration of flight model into the satellite, the communication with the satellite and the functional test were passed. The NISS will be launched in early 2018. During around 2-year operation, the spectro-photometric survey covering more than 100 square degree will be performed. To achieve the major scientific objectives for the study of the cosmic star formation in local and distant universe, the main observational targets will be nearby galaxies, galaxy clusters, star-forming regions and low background regions. Here, we report the final performance of the flight model of the NISS.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.39.4-40
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• 2017

According to the Korean government's Long-term Space Development Plan 2040, "Creative space science research" is included in a statement to investigate the origin and evolution of the universe by conducting a series of Korean space telescope missions: launch of space telescopes on a small satellite and an international collaboration explorer by 2020, a mid-size domestic space telescope by 2030, and a large size Korea leading international space telescope by 2040. We studied the feasibility of the future Korean Space Telescope (KST) for a mid-size domestic satellite platform. In order to pursue the uniqueness of the science program, we consider a wide range of observing wavelength (0.2um ~ 2.0um) with a spectral resolution of R~6 in the NUV and optical bands, and R~30 for NIR, utilizing an off-axis TMS(Three Mirror System) optics with a wide field of view ($2{\times}4$ degrees) which is optimized for ultra-low surface brightness sources. The main science goals of the mission include investigations of the galaxy formation, cosmic web, and the cosmic background radiation in the NUV-NIR regions. In this paper, we present the science cases and several technical challenges to be resolved along with the future milestones for the success of the KST mission.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.37.2-37.2
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• 2016

There exist scaling relations that link the mass of supermassive black holes with both the velocity dispersion and the mass of the central stellar cusp of their host galaxies. This implies that galaxies co-evolve with their central black holes, potentially through the feedback from actively accreting supermassive black holes (AGN). We use integral field spectroscopy data from the 8.2m Gemini-North telescope to investigate ionized gas outflows in luminous local (z<0.1) Type 2 AGN. Our sample of 6 galaxies was selected based on their [OIII] dust-corrected luminosity (>$10^{42}erg/s$) and signatures of outflows in the [OIII] line profile of their SDSS spectra. These are arguably the best candidates to explore AGN feedback in action since they are < 1% of a large local type 2 AGN SDSS sample selected based on their [OIII] kinematics. Expanding on previously reported results concerning the kinematic decomposition and size determination of these outflows, here we report their photoionization properties and energetics. We find strong evidence that connect the extreme kinematics of the ionized gas with AGN photoionization. The kinematic component related to the AGN-driven outflow is clearly separated from other kinematic components, such as gravitation- or stellar-driven motions, on the velocity and velocity dispersion diagram. Our spatially resolved kinematic analysis reveals that up to 90% of the mass and kinetic energy of the outflow is contained within the central kiloparcec of the galaxy. The total mass and kinetic energy of the outflow correlate well with the AGN bolometric luminosity, resulting in energy conversion efficiencies between 0.01% and 1%. Intriguingly, we detect ubiquitous signs of ongoing circumnuclear star formation. Their small size, the centrally contained mass and energy, and the universally detected circumnuclear star formation cast doubts on the potency of these AGN-driven outflows as agents of negative feedback.

• YAKHAK HOEJI
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• v.51 no.1
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• pp.13-34
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• 2007

Traditional Medicine (TM) is called as philosophical medicine in Korea. An unified theory named as Sihnsang-hanron (SSHR) was hypothesized through studies of scientific analyses on various theories of TM. SSHR has extracted seven concepts which are six common ones from the great three books (三大原典) and the Logic of Laotzu & Chuangtzu (老莊思想). Six common concepts are the affecting by cold (傷寒), qi (氣), cold or heat (寒熱), exterior & interior of body (表裏), deficiency or excessiveness (虛實), and yin & yang (陰陽). We have tried to apply these seven concepts to Physics and Life Science. The affecting by cold means anti-sunlight and the origin of all diseases. The difference between TM and modern medical science would be in diagnostic methods as well as their theoretical analyses for various diseases. The modern science follows Haeckel's positive dialectics applied by the biological monism, and oriental one(SSHR) does Yin-Yang monism from the studies of Logic of Laotzu (老子) & Chuangtzu (莊子). SSHR would make the theory of exterior & interior of body (表裏論) and six channels (六經) develope scientifically as a diagnostic technique of disease. This theory is an excellent one that can't be found out in modern medical science, and so it should be developed as a scientific theory by using modern mechanic instrument. Chuangtzu asserted that ai was the basic substance of the universe. It is hypothesized that qi (氣) is like small particles -higgs, with dynamic power in modern Physics. We consider cautiously qi could be calculated by mathematics through higgs' bosons in near future.

• Journal of the Korean Society for Library and Information Science
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• v.43 no.3
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• pp.85-105
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• 2009

Disagreements between the technical environment and the conventional library catalog have caused a re-clarification of International Cataloguing Principles (ICP). Review is under way to finalize the publication of RDA (Resource Description and Access) in late 2009 by the Joint Steering Committee for Development of RDA. The impending RDA is based on FRBR (Functional Requirements for Bibliographic Records) which re-explains the bibliographic universe focused on entities, attributes and relationships between resources, but tries to maintain MARC as an encoding format for RDA. In this study, firstly FRBR, ICP and RDA were analyzed. Secondly, we propose 3 scenarios of RDA implementation: the future cataloging system based on the FRBR Entity, using a semantic web structure, and the scenario using the existing MARC format with some small changes. Finally, by examining response patterns of overseas bibliographic institutions, we present a set of urgent issues for future directions of bibliographic contro in Korea which includes, but not limited to, relationship between RDA/FRBR and KCR (Korean Cataloging Rules), continuation of KORMARC and authority control.