• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.33.2-33.2
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• 2016

Since the serendipitous discovery of a large-scale atomic hydrogen ($H_I$) ring discovered in the Leo I galaxy group, its origin has been under debate till today, whether it is the leftover after group formation or stripped gas structure during the galaxy-galaxy interaction. Intriguingly a number of $H_I$ clumps have been identified along the gas ring, some of which turn out to be associated with optically catalogued dwarf galaxies. The formation history based on detailed optical and $H_I$ gas properties of those dwarf galaxies will enable us to verify the origin of the Leo ring. In this work, we first probe the redshift and multi-color properties of those dwarf galaxies, using deep photometric and spectroscopic data from CFHT, Gemini and Magellan telescope.

• 한국문화재보존과학회:학술대회논문집
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• 2004.10a
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• pp.131-134
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• 2004

A lot of foreign objects(ceramics, pottery, bronze, glassware and coins, etc.) have been found in the archaeological sites in Korea. These foreign objects are the evidences of the cultural exchanges of that time, whose scale and routes are an important part of the studies in ancient history. So it is crucial to accumulate basic reference information such as the raw materials and the production method of these objects through scientific researches, along with archeological researches. These scientific research materials provide a basis for finding the importing route and the origin of these objects. Besides, we can find out extraordinary and distinctive production technique by comparison with tile domestic objects. This article reports the result of an analysis, performing on 36 samples of the glassware fragments excavated from the South Tomb of the Hwangnamdaechong, to verify their components and note peculiar features. We have analyzed the major and minor components of 10 elements, and then by using these data examined the differences in the composition of components, varying with the origin and color of glassware. We used the PCA(principal component analysis) as the statistical method to classify the sample in order to find out how the samples formed groups.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.38.2-38.2
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• 2019

In the history of universe, galaxies are consistently affected by surrounding medium and neighbor galaxies. These effects control galaxy evolution, making properties of galaxies diverse and dependent on environments. We investigate environments of various types of galaxies and how they affect galaxy properties, such as bar structures and galaxy sizes, etc. First, we present the observational evidence that bars can form from a cluster-cluster interaction. The evidence indicates that bars can form due to a large-scale violent phenomenon, and cluster-cluster interaction should be considered as an important channel for bar formation. Second, we discover for the first time that local early-type galaxies heavier than 1011.2 Msol show a clear environmental dependence in mass-size relation, in such a way that galaxies are as much as 20 - 40% larger in densest environments than in underdense environments. This result suggests that mergers played a significant role in the growth of massive galaxies in dense environments as expected in theory. Lastly, we investigate environments of the most massive galaxies and extremely massive quasars. By doing so, we find that massive galaxies are a much better signpost for galaxy clusters than massive quasars.

• Korean Journal of Plant Taxonomy
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• v.53 no.2
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• pp.148-156
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• 2023

Hibiscus hamabo (Malvaceae) is a deciduous shrub mainly found in northeast Asia, including China, Japan, and Korea. Due to its limited distribution on Jejudo Island and at several sites in Jeollanam-do in Korea, H. hamabo has been designated as an endangered species by the Ministry of the Environment and has been the subject of several restoration programs. In this study, we quantified genetic variations using double-digestion restriction-associated DNA sequencing technology in 96 individuals of H. hamabo from 13 distinct populations in Korea. We determined 3,352 genome-wide single nucleotide polymorphism loci after stringent filtering processes and analyzed the level of genetic variation within and among populations as well as the population differentiation and genetic ancestry with various assumptions pertaining to the population origin. Our results indicated weak differentiations among populations surveyed in this study but clearly suggested that most of the H. hamabo populations maintain a relatively high level of genetic diversity as evidence of frequent genetic exchanges among populations via outcrossing or sequential gene flows. For a more detailed analysis of the origin of Korean H. hamabo and its demographic history, it will be necessary to expand sampling in China and Japan.

• The Journal of Korean Medicine
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• v.33 no.1
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• pp.160-168
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• 2012

Objectives: Cynanchi wilfordii Radix has commonly been used with or instead of Polygoni multiflori Radix in Korea. The purpose of this study was to investigate their history in the traditional Oriental medical literature and quantitative determination of conduritol F from Cynanchi wilfordii Radix according to various harvest times. Methods: We conducted studies of the traditional Oriental medical literature and analysis of the component, conduritol F, simultaneously. Efficacy and origin of Cynanchi wilfordii Radix in literature study, time of harvest in component research. Chromatographic analysis performed using Silica(2) 100A column (Phenomenex 5 um, 250 mm 4.6 mm) with a mixture of acetonitrile and water (98 : 2)(v/v). The analyses detected at UV (210 nm). Results: Conduritol F was detected in Cynanchi wilfordii Radix, but in Cynanchi auriculati Radix was not. We indicate that conduritol F is as a distinguishable indicator with other materia medica. We think the proper harvesting time is October and November. Conclusions: Measures of trunk control were significantly related with values of dynamic balance and gait. Based on these results, trunk control is an essential core component of balance and gait. Trunk control training programs after stroke should be developed and emphasized.

• Journal of Korean Medical classics
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• v.36 no.4
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• pp.69-91
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• 2023

Objectives : This study investigates the association between disease behind the Beijing Epidemic of 1232 and fever causing internal damages as mentioned in the Neiwaishang Bianhuolun. Methods : In order to narrow the fever causing diseases in the Neiwaishang Bianhuolun, the retrospective diagnostic method was used in analysis. Disease behind the 1232 Beijing Epidemic and the fever causing internal damages were categorized. Results : Fever causing diseases in the Neiwaishang Bianhuolun could be categorized as infectious disease, inflammatory disease, irritable bowel syndrome, and fever of unknown origin. The Beijing Epidemic was limited in scale with high fatality, of which possible diseases include infectious disease and inflammatory disease with epidemic medium. Fever from internal damage has a mild prognosis, is non-epidemic, and lacks accompanying symptoms such as acute stomachache, even when it happens with external damage. This narrows the possible diseases to IBS and fever of unknown origin. Conclusions : Among internal damage fever cases treated by Li Dongyuan, there were infectious diseases from the 1232 epidemic and inflammatory diseases with mild prognosis.

• Annals of Clinical Neurophysiology
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• v.9 no.1
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• pp.1-4
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• 2007

Vertigo is an illusion of rotation, which results from an imbalance within the vestibular system. This review focuses on two common presentations of spontaneous vertigo: acute prolonged spontaneous vertigo and recurrent spontaneous vertigo. Common causes of acute prolonged spontaneous vertigo include vestibular neuritis, labyrinthitis, and brainstem or cerebellar stroke. The history and detailed neurological/neurotological examinations usually provide the key information for distinguishing between peripheral and central causes of vertigo. Brain MRI is indicated in any patient with acute vertigo accompanied by abnormal neurological signs, profound imbalance, severe headache, and central patterns of nystagmus. Recurrent spontaneous vertigo occurs when there is a sudden, temporary, and largely reversible impairment of resting neural activity of one labyrinth or its central connections, with subsequent recovery to normal or near-normal function. Meniere's disease, migrainous vertigo, and vertebrobasilar insufficiency (VBI) are common causes. The duration of the vertigo attack is a key piece of information in recurrent spontaneous vertigo. Vertigo of vascular origin, such as VBI, typically lasts for several minutes, whereas recurrent vertigo due to peripheral inner-ear abnormalities lasts for hours. Screening neurotological evaluations, and blood tests for autoimmune and otosyphilis are useful in assessment of recurrent spontaneous vertigo that are likely to be peripheral in origin.

• Journal of Korean Medical classics
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• v.32 no.1
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• pp.75-93
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• 2019

Objectives : This study is to reveal the origin of Mingtangyangfutu in "YiXueRenMen". Methods : This study compares and analyzes it with MingTang diagrams in reference books of "YiXueRenMen", MingTang diagrams and diagrams of bronze statues for acu-moxibustion in those days. Results : The origins of Mingtangyangfutu cannot be found in the citations. The argument that it is copied and simplified from MingTang diagrams in "JinLanXunJing(金蘭循經)" lacks its grounds. As MingTang diagrams in "TongRenShuXueZhengJiuTuJing" and "ZhenJiuJuYing" have less information than it, they were nothing more than references when it drew. Apparel of man, the first acupoint, the last acupoint and orders of acupoints of their meridians in it are different from ones in MingTang diagrams and diagrams of bronze statues for acu-moxibustion. Conclusions : Mingtangyangfutu is not a copied and simplified version of MingTang diagrams in "JinLanXunJing", but is one to add new information for MingTang diagrams in "TongRenShuXueZhengJiuTuJing", "ZhenJiuJuYing", or has a separate rationale (Gajeongdongin(嘉靖銅人) related to at the time.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.37.4-38
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• 2018

The HULQ project proposes to use gravitational lensing to determine the masses of QSO host galaxies, an otherwise difficult goal. If these host galaxy masses, along with their SMBH masses from single-epoch measurements, are estimated for a substantial number of QSOs at various redshifts, the co-evolution of SMBHs and their host galaxies can be studied for a large portion of the history of the universe. To determine the feasibility of this study, we present how to estimate the number of sources lensed by QSO hosts, i.e. the number of lensing QSO host galaxies (hereafter QSO lenses). SMBH masses in the literature are transformed into the velocity dispersions of their host galaxies using the M_BH -sigma relation, and in turn the Einstein radii for each QSO -source redshift combination is calculated, assuming singular isothermal spherical mass distributions. Using QSOs and galaxies as potential sources, the probability of a QSO host galaxy being a QSO lens is calculated, as a function of limiting magnitude. The expected numbers of QSO lenses are estimated for ongoing and future wide-imaging surveys, and the Hyper Suprime-Cam Wide survey is illustrated as an example.

• Korean journal of communication and information
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• v.64
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• pp.85-108
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• 2013

This paper aims to review Ahn Jae-Hong's studies on the history of the Korean press from the perspective of research history focussing his "Josun Shinmun Sosa(A Short History of the Korean Press)" published in 1935. For this purpose major discussions with respect to journalistic history during the Japanese occupation period are reviewed. The result reveals that Ahn Jae-Hong's studies using a comparative method and a social historical approach are judged to be the most representative outcomes at that time. The "Josun Shinmun Sosa" first explains "Inhaeng Jobo" and "Jeobo" as an origin of newspaper, and then explains various subjects on newspaper phenomena in the latter era of the Chosun Dynasty such as participants of major newspapers, the tone of newspapers, the analysis of newspaper character through evaluation of main articles, the system of newspaper, newspaper advertisements, pro-Japanese newspapers, newspapers managed by Japanese, newspapers for overseas Korean, etc. But partly it gives a general description rather than a detailed research due to the nature of contributions to the newspaper, and also includes an objective analysis and a subjective impression together. Nevertheless his researches can be valued as pioneering pieces of work as they comprehensively handled various objects of study on newspapers and gave new angle and orientation of interpretation on the newspaper phenomena at that time. Also it is judged that they had an effect on the period division as well as the description methods for the study of the history of the Korean press.