• Publications of The Korean Astronomical Society
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• v.15 no.spc2
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• pp.45-52
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• 2000

Four plasma instruments are currently under development for KAISTSAT-4 (K-4) which is scheduled for launch in 2002. They are the Solid-State Telescope, Electro-Static Analyzer, Langmuir Probe, and the Scientific Magnetometer, that will respectively allow in-situ detection of high energy and low energy components of auroral particles, ionospheric thermal electrons, and magnetic field disturbances. These instruments, together with the Far-ultraviolet IMaging Spectrograph, will provide micro-scale physics of Earth's polar ionosphere with detailed spectral information that has not been previously achieved with other space missions. In this paper, we review the concept of the four space plasma instruments as well as the anticipated results from the instruments.

• Journal of The Korean Astronomical Society
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• v.36 no.spc1
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• pp.125-133
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• 2003

New Jersey Institute of Technology (NJIT), in collaboration with the University of Hawaii (UH), is upgrading Big Bear Solar Observatory (BBSO) by replacing its principal, 65 cm aperture telescope with a modern, off-axis 1.6 m clear aperture instrument from a 1.7 m blank. The new telescope offers a significant incremental improvement in ground-based infrared and high angular resolution capabilities, and enhances our continuing program to understand photospheric magneto-convection and chromospheric dynamics. These are the drivers for what is broadly called space weather - an important problem, which impacts human technologies and life on earth. This New Solar Telescope (NST) will use the existing BBSO pedestal, pier and observatory building, which will be modified to accept the larger open telescope structure. It will be operated together with our 10 inch (for larger field-of-view vector magnetograms, Ca II K and Ha observations) and Singer-Link (full disk H$\alpha$, Ca II K and white light) synoptic telescopes. The NST optical and software control design will be similar to the existing SOLARC (UH) and the planned Advanced Technology Solar Telescope (ATST) facility led by the National Solar Observatory (NSO) - all three are off-axis designs. The NST will be available to guest observers and will continue BBSO's open data policy. The polishing of the primary will be done in partnership with the University of Arizona Mirror Lab, where their proof-of-concept for figuring 8 m pieces of 20 m nighttime telescopes will be the NST's primary mirror. We plan for the NST's first light in late 2005. This new telescope will be the largest aperture solar telescope, and the largest aperture off-axis telescope, located in one of the best observing sites. It will enable new, cutting edge science. The scientific results will be extremely important to space weather and global climate change research.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.73.2-73.2
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• 2012

Matusoka & Kawara (2010) showed that the number density of the most massive galaxies (log $M/M_{\odot}=11.5-12.0$) increases faster than that of the next massive group (log $M/M_{\odot}=11.0-11.5$) during 0 < z < 1. This appears to be in contradiction to another important empirical concept of "downsizing". We attempt to understand the two observational findings in the context of the hierarchical merger paradigm using semi-analytic techniques. Our models closely reproduce the result of Matusoka & Kawara (2010). Downsizing can also be understood as larger galaxies have on average smaller assembly ages but larger stellar ages. Our fiducial models further reveal the details on the history of stellar mass growth of massive galaxies. The most massive galaxies (log $M/M_{\odot}=11.5-12.0$ at z=0), which are mostly brightest cluster galaxies, obtain roughly 70% of their stellar components via merger accretion. The role of merger accretion monotonically declines with galaxy mass: 45% for log $M/M_{\odot}=11.0-11.5$ and 20% for log $M/M_{\odot}=10.5-11.0$ at z = 0. The specific accreted stellar mass rates via galaxy mergers decline very slowly during the whole redshift range, while the specific star formation rates sharply decrease with time. In the case of the most massive galaxies, merger accretion becomes the most important channel for the stellar mass growth at z ~ 2. On the other hand, in-situ star formation is always the dominant channel in the $L_*$ galaxies.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.54.3-54.3
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• 2015

To probe the star formation in local and early Universe, the NISS with a capability of imaging spectroscopy in the near-infrared is being developed by KASI. The main scientific targets are nearby galaxies, galaxy clusters, star-forming regions and low background regions. The off-axis optical design of the NISS with 15cm aperture was optimized to obtain a wide field of view (FoV) of $2deg.{\times}2deg.$ as well as a wide spectral coverage from 0.9 to $3.8{\mu}m$. The opto-mechanical structure was designed to be safe enough to endure in both the launching condition and the space environment. The dewar will operate $1k{\times}1k$ infrared sensor at 80K stage. The NISS will be launched in 2017 and explore the large areal near-infrared sky up to $200deg.^2$ in order to get both spatial and spectral information for astronomical objects. As an extension of the NISS, KASI is planning to participate in a new small space mission together with NASA. The promising candidate, SPHEREx (Spectro-Photometer for the History of the Universe Epoch of Reionization, and Ices Explorer) is an all-sky survey satellite designed to reveal the origin of the Universe and water in the planetary systems and to explore the evolution of galaxies. Though the survey concept is similar to that of the NISS, the SPHEREx will perform the first near-infrared all-sky imaging spectroscopic survey with the wider spectral range from 0.7 to $5{\mu}m$ and the wider FoV of $3.5deg.{\times}7deg.$ Here, we report the current status of the NISS and introduce new mission for the near-infrared imaging spectroscopic survey.

• Journal of Science Education
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• v.34 no.1
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• pp.47-57
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• 2010

The purpose of this study was to investigate how the lesson using the newly developed Phase Change Model of Venus can change ninth graders' geocentrical concept related to the progression of the phase of Venus. In order to know students' concept change of the progression of the phases of Venus, test sheets and a questionnaire regarding solar systems were developed and used pre and post test. The results showed that many students have an astronomical preconception of geocentricism, and some students have an especially poor scientific understanding of the solar system. However, there were significant changes in students' conceptual levels (p<.05) after teaching with the Venus's Phase Change Model. Therefore, teaching with the Phase Change Model of Venus was effective on students' scientific conceptual change from geocentricism to heliocentricism.

• Journal of architectural history
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• v.10 no.2 s.26
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• pp.7-19
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• 2001

Ip-am valley, located at the eastern remote part of Korean peninsular was the place where a remarkable Confucian scholar Chang Hyon-gwang spent his secluded days. A large upright stone, called Ip-am, and undulating streams nearby were surrounded by mountains, which formed a large enclosed valley. After selecting 28 natural and artificial places, Chang named each of them. Chang compared the relationship between Ip-am and the 28 places with that of the Polestar and 28 Lunar Lodgings, which were known as the ancient Chinese astronomical concept. Also, Chang regarded the valley as a place where the Taoistic Deity could stay. Chang, who had deep knowledge of astronomy, wrote some books on it. It could be said that the comparison of his hermitages with the Polestar and the 28 Lunar Lodgings resulted from his deep passion for astronomy. He considered the Ip-am valley to be the core of the universe like the Polestar is the core of the celestial world. Some stars like the Polestar or the Dipper were regarded as the Deities of Taoism. We can find that Confucian scholars of the middle Choseon, like Chang Hyon-gwang, also tended to have some concern about Taoism.

• Progress in Superconductivity and Cryogenics
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• v.24 no.4
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• pp.71-77
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• 2022

Sub-Kelvin cooling has been generally demanded for the fields of low temperature physics, such as physical property measurements, astronomical detection, and quantum computing. The refrigeration system with a small size can be appropriately introduced when the measurement system does not require a high cooling capacity at sub-Kelvin temperature. The dilution refrigerator which is a common method to reach sub-Kelvin, however, must possess a large ³He circulation equipment at room temperature. As alternatives, a sorption refrigerator and a magnetic refrigerator can be adopted for sub-Kelvin cooling. This paper describes those coolers which have been developed by various research groups. Furthermore, a cold-cycle dilution refrigerator of which the size of the ³He circulation system is minimized, is also introduced. Subsequently, a new concept of dilution refrigerator is proposed by our group. The suggested cooler can achieve sub-Kelvin temperature with a small size since it does not require any recuperator and turbo-molecular vacuum pump. Its architecture allows the compact configuration to reach sub-Kelvin temperature by integrating the sorption pump and the magnetic refrigerators. Therefore, it may be suitably utilized in the low temperature experiments requiring low cooling capacity.

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.1
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• pp.201-208
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• 2022

As around the world, ground and underground transportation capacity is reaching its limit, centering on urban areas. As urban traffic becomes congested, time and cost are astronomical, and environmental destruction caused by urban pollution is becoming increasingly serious. As a way to solve this problem, the means of flying over the air are in the spotlight as the next generation of future transportation, and the concept of urban air mobility (UAM, Urban Air Mobility) is defined as systematic planning. The development of an electric-powered vertical take-off (eVTOL) aircraft that obtains electric power through a battery using a personal aerial vehicle (PAV) as a means of transportation has accelerated. As the aircraft development of new technology aircraft in the evtol method is actively carried out, the need to prepare systems such as aircraft certification standards, pilot qualification systems, and qualification management is emerging. The Federal Aviation Administration (FAA) and the European Union Aviation Safety Agency (EASA), which lead international standards, announced new special technical conditions and temporary regulations SCVTOL-01, respectively. However, the pilot qualification system for operating the uam aircraft has not yet been clearly announced. Therefore, this paper analyzes the recently announced FAA regulations and EASA regulations to identify differences and directions in perspectives on UAMs and study the existing vertical take-off and landing aircraft (VTOL) pilot qualification system to present directions for qualification classification.

• Journal of the Korean Society of Earth Science Education
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• v.17 no.1
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• pp.34-48
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• 2024

With the global rise in interest in competency-based education, the Ministry of Education of the Republic of Korea outlined six core competencies in the 2015 revised curriculum, essential for future society's 'creative and convergent talent'. This study introduces an HTE-STEAM constellation education program designed to develop the core competencies outlined in the 2015 revised curriculum and address the limitations of hands-on astronomy education. The program's effectiveness was assessed through a pilot test. The program was implemented at G Library, an out-of-school education site in Cheongju-si, Chungcheongbuk-do, targeting students from 3rd to 6th grade. The study's results include: First, the HTE-STEAM program significantly impacted all aspects of the STEAM attitude test except for 'self-concept', particularly influencing 'science and engineering career choice', 'consideration', and 'communication'. Thus, it has led to positive outcomes in the cultivation of future society's core competencies, including 'creative thinking skills', 'communication skills', and 'community skills'. Secondly, the HTE-STEAM constellation education program, despite covering the challenging concept of spacetime, was deemed easy by many students. Observations of students applying the spatial concepts they learned by using teaching aids suggest that the program was effective in enhancing students' understanding of the spatial structure of the sky and the universe. Additionally, this program aligns with the 2022 curriculum's updated standards for understanding the sky's spatial structure. Consequently, the HTE-STEAM constellation education program positively cultivates future society's core competencies and serves as a valuable complement to night observation practices in schools.

• Journal of the Korean earth science society
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• v.32 no.2
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• pp.200-211
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• 2011

The purpose of this study is to investigate the effects of astronomical animation module on students' conceptual change regarding the concepts of diurnal motion of stars. Four students participated in this study, who never learned about the diurnal motion of stars. An animation module was developed by using Flash MX to readily understand the concept of space. In addition, we inserted a teacher's voice with supplementary materials into the animation module to help students learn individually. The animation module was comprised of the movement of the Earth, the Moon and the planet. The earth science gifted students' preconception on diurnal motion of stars was analyzed with pre-test using questionnaires and interviews. After the instruction with animation module, the effect of conceptual change was examined by comparing pre and post-test. The results indicated that three students correctly presented about the motion of the star by all directions in middle latitude. Four students showed their understanding that stars travelled straight in all directions. Finally, all of four students whose preconceptions were that the star rotated perpendicularly showed the conceptual change of diurnal motion that the star traveled diagonally.