• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.44.2-45
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• 2016

We present near-infrared photometric properties of red supergiant stars (RSGs) in three galaxies NGC 4449, NGC 5055 and NGC 5457. The near-infrared imaging data of WFCAM UKIRT were used and combined with optical archive data to identify the RSGs in the galaxies. We found that the RSGs can be identified from the foreground Galactic stars in (i-K, ri) colour-colour diagram. The effective temperatures and luminosities of the identified RSGs are estimated from JHK photometry using MARCS model. In the H-R diagram, the majority of RSGs in the galaxies are distributed between $logL/L{\odot}=4.8$ and 5.7, and their effective temperature and luminosities agree with the current evolutionary tracks with masses in the range $9-30M{\odot}$. We also compared the spatial distribution of RSGs with the HII regions. A tight spatial correlation between RSGs and HII region was found in NGC 4449 and NGC 5457. We do not find a clear metallicity dependance on the RSG effective temperature in the three galaxies, but the maximum luminosity of the three galaxies is constant at $logL/L{\odot}{\sim}5.6$. Additional spectroscopy data, including photometry are essential to examine whether the physical properties of RSGs change with metallicity.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.1
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• pp.59.2-59.2
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• 2013

Wilson and Bappu found a tight correlation between the stellar absolute visual magnitude (MV) and the width of the Ca II K emission line for late-type stars in 1957. Here, we revisit the Wilson-Bappu relationship (hereafter, WBR) to claim that WBR can be an excellent indicator of stellar surface gravity of late-type stars as well as a distance indicator. We have measured the width (W) of the Ca II K emission line in high resolution spectra of 125 late-type stars, which were obtained with Bohyunsan Optical Echelle Spectrograph (BOES) and adopted from the UVES archive. Based on our measurement of the emission line width (W), we have obtained a WBR of $M_V=33.76-18.00{\log}W$. In order to extend the WBR to be a surface gravity indicator, the stellar atmospheric parameters such as effective temperature ($T_{eff}$), surface gravity (logg), metallicity ([Fe/H]), and micro-turbulence (${\xi}_{tur}$) have been derived from the self-consistent detailed analysis using the Kurucz stellar atmospheric model and the abundance analysis code, MOOG. Using these stellar parameters and logW, we found that ${\log}g=-5.85\;{\log}W+9.97\;{\log}T_{eff}-23.48$ for late-type stars.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.6
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• pp.316-323
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• 2019

Objectives: This study aimed to determine the prevalence of odontogenic cysts, tumors, and other lesions among reports in the archives of the Department of Oral and Maxillofacial Surgery at the Faculty of Dentistry affiliated with Kocaeli University collected over a four-year period. Materials and Methods: In this retrospective study, patient records from the archive of the Department of Oral and Maxillofacial Surgery from 2014 to 2018 were reviewed. Patient demographic information (age and sex) and lesion location were recorded and analyzed. Results: From a total of 475 files reviewed, odontogenic cyst was confirmed in 340 cases (71.6%), and odontogenic tumor was confirmed in 52 cases (10.9%). Regarding odontogenic cyst type, the most common was radicular cyst (216 cases), followed by dentigerous cyst (77 cases) and odontogenic keratocyst (23 cases). Among odontogenic tumors, the most frequent was odontoma (19 cases), followed by ossifying fibroma (18 cases) and ameloblastoma (9 cases). Giant cell granuloma was also reported in 35 cases. Conclusion: The distribution pattern of odontogenic cysts and tumors in our retrospective study is relatively similar to that reported in the literature. Complete clinical reports for final diagnosis of these lesions and routine follow-up examinations are very important for treatment.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.68.2-68.2
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• 2012

We present a discovery of two new globular clusters in the Hubble Space Telescope archive images of the M81 group. They are located much farther from both M81 and M82 in the sky, compared with previously known star clusters in these galaxies. Both clusters show that higher luminosity and larger effective radius than typical globular clusters in Milky Way and M81. Using the available spectroscopic data provided by the Sloan Digital Sky Survey, we derive a low metallicity with [Fe/H] ${\approx}$ -2.3 and an old age ~14 Gyr for GC-2. The I-band magnitude of the tip of the RGB for GC-1 is consistent with that of the halo stars in the GC-1 and GC-2 field. However, that of GC-2 is 0.26 mag fainter than its field. It shows that GC-2 is about 400 kpc behind the M81 halo along our line of sight. The deprojected distance to GC-2 from M81 is much larger than any other known globular clusters in the local universe. We discuss the possible scenarios to explain the existence of globular cluster in such an extremely isolated environment.

• Weed & Turfgrass Science
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• v.3 no.3
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• pp.240-245
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• 2014

This study was carried out to determine the possible use of volcano eruption sand at Merapi mountain area compared with clayey soil, alfisol as turfgrass growing media. Indonesia has abundant source of eruption sand and clayey soil. Native zoysiagrass (Z. matrella) was collected from Sleman district and seashore paspalum (P. vaginatum) from Solo region. The experimental plots were treated with both organic and inorganic fertilizers. Zoysiagrass and seashore paspalum can grow on the mixture of eruption volcano sand and alfisol soil. Fertilizers application increased turf color, surface coverage rate and recovery rate of turfgrass. While fertilizer treated alfisol have no effect on the length and dry weight of zoysiagrass root. Mixing of volcano eruption sand on growing media resulted in longer root length, higher shoot dry weight of zoysiagrass than in alfisol soil. Type of fertilizer affected the pH, soil organic matter, total N, available P, available K and electrical conductivity of sand and alfisol after cultivation. Similarly to zoysiagrass, the recovery of seashore paspalum was increased by application of fertilizer, even the inorganic fertilizer showed faster recovery than organic fertilizer. Surface coverage of seashore paspalum was faster than that of zoysiagrass with or without fertilizer.

• Weed & Turfgrass Science
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• v.3 no.3
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• pp.221-224
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• 2014

Genetically modified (GM) crops are not permitted to be cultivated in Korea, but can only be imported as food or feed purposes. The import of GM crops has sharply increased in recent years, thus raising concerns with regard to the unintentional escape of these crops during transport and manufacturing as well as the subsequent contamination of local, non-GM plants. Hence, monitoring of GM crops was studied in or outside of grain receiving ports as well as from feed-processing plants in Korea during July 2008. We observed spilled maize grains and established plants primarily in storage facilities that are exposed around the harbors and near transportation routes of the feed-processing areas. Based on the PCR analyses, a total of 17 GM maize plants and 11 seeds were found among the samples. In most cases, the established maize plants found in this study were at the vegetative stage and thus failed to reach the reproductive stage. This study concludes that, in order to prevent a genetic admixture in the local environment for GM crops or seeds, frequent monitoring work and proper action should be taken.

• The korean journal of orthodontics
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• v.52 no.6
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• pp.432-438
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• 2022

Objective: To compare crown-root angulations of the permanent maxillary anterior teeth in skeletal Class I, Class II, and Class III Korean malocclusion patients using cone-bean computed tomography (CBCT) images. Methods: Sixty CBCT images were collected from orthodontic patients archive based on skeletal Class I (0˚< A point-nasion-B point angle [ANB] < 4˚), Class II (ANB ≥ 4˚), and Class III (ANB ≤ 0˚) to have 20 samples in each group. Mesiodistal crown-root angulation (MDCRA) and labiolingual crown-root angulation (LLCRA) were evaluated after orientation of images. Crown-root angulations were compared among Class I, Class II, and Class III groups and among the maxillary anterior teeth in each group. Results: LLCRAs of the maxillary central incisor and the lateral incisor were significantly lower in Class III group than those in Class I group. However, those of the canine showed no significant differences among groups. MDCRAs of the maxillary anterior teeth did not significantly differ among groups either. Conclusions: Our results suggest that skeletal Class III malocclusion might affect LLCRA of the maxillary incisors, especially the central incisor.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.9 no.10
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• pp.753-762
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• 2019

It is very important to use the raw material in a particular field of research or education. Research without raw materials are difficult to prove and often remain hypothesis. The use of the raw material is also important in area studies that study specific areas. However, research of area studies, especially Western history, raw material and historical archives are very important data, but it is difficult to obtain and refer to these data due to physical or spatial constraints. In order to solve this problem, there is a method of collecting and providing historical archives, but it is currently difficult to find a case of providing overseas historical archives as a web system in Korea. Accordingly, in this paper proposes the necessity of collecting historical archives, the method of collection, and the method of digital archiving of collected data structurally and systematically. In this regard, investigate the existing research cases on the archive system and database design, and it description the differentiation between the existing systems and the modeling method proposed in this study. Also, to improve the efficiency of the search, it proposes a method of adding a tag table when database modeling.

• Journal of Conservation Science
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• v.34 no.6
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• pp.443-458
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• 2018

An archive is a collection of documents or records. Currently, most archived documents are made of paper. Paper is susceptible to biological damage and deterioration due to its material properties. To control the biological damage, treatment with chemical disinfectants and control of the storage environment are often used. In government-controlled bulk public archives, all documents are chemically sterilized before storage. However, an extremely large quantity of public records have been produced, and storage space and conservation management are gradually reaching their limits. In this study, 60 species of microbes were identified using a genetic method. We successfully applied the adenosine triphosphate (ATP) bioluminescence method to detect microbial contamination on paper documents. A calibration curve of the ATP bioluminescence as a function of the microbe quantity was obtained, and the microbial activity on non-sterilized paper archives from 1951 was analyzed using an ATP luminometer. It was found that the microbial activity was suppressed or reduced in climate-controlled storage environments at $22^{\circ}C$ and 55% relative humidity. We anticipate that these results will be used to establish selective sterilization systems for government-controlled bulk public archives.

• Korean Journal of Heritage: History & Science
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• v.42 no.3
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• pp.88-104
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• 2009

Changes in a society and visual media has a tight relationship. Photography represented the last 20th century in the visual media; while the 21st century we live in is represented by moving image(video). The change of visual media also brought changes to the archaeological recordings. As information is gathered from the field work in archaeology, it seems that use of video recording, a reliable way of collecting and recording data, will increase. The process of archaeological excavations can be considered as a contents itself. Also, video recording has many advantages when recording environmental surrounding of the sites and artifacts, for the reservation of the scenery, and as recorded heritage of the humankind. Video recording can be a tool of conversion to public archaeology to devote to its social and academic roles. Considering all of the above, studying ways to record and preserve visual materials is essential in the field of archaeology and we should be prepared for it. We strongly propose reinstatement of the visual archaeology, which should be studied in archaeological perspective. The direction of the study of visual archaeology can be summarized into two. First is the study on the video recording during field work and the archive of video recordings. Second is the study on the media as the tool of communication. More detailed and organized research should be considered in depth in the archaeological theory and methods.