• Journal of the Korean Society of Radiology
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• v.15 no.5
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• pp.675-681
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• 2021

Recently, the Ministry of Education stipulates in the distance class operation regulations that student lecture evaluations for distance learning subjects should be conducted at least twice per semester and the results should be disclosed to students. Therefore, the lecture evaluation of D college was compared with the first semester of 2020 and the first semester of 2021. As for the multiple-choice evaluation result of the distance learning mid-course evaluation, the overall average of the mid-course evaluation of the distance class in the first semester of 2020 increased from 4.1819 to 4.4000 in the mid-course evaluation in the first semester of 2021.In the case of the first semester of 2020, due to Corona 19, all non-face-to-face classes were held, but in the first semester of 2021, face-to-face classes increased. The overall satisfaction level rose from 4.18 points in the first semester of 2020 to 4.39 points in the first semester of 2021. The screen composition, sound and picture quality, playback time, face appearance, lecture material provision, and frequency of use of the top 3% and bottom 3% also increased. Despite the changes caused by the LMS replacement, which was a concern, student attendance, assignments, and test submission rates also increased compared to the previous year. The null hypothesis that 'the difference between the two scores is the same' is the null hypothesis because the probability of significance is 0.000 and less than 0.05 in the case of the best 3% of the test result of the test result of the mid-course evaluation of distance classes in the first semester of 2020 and the evaluation of the intermediate lectures in the first semester of 2021. As this was rejected, it can be seen that the best score for the 2021 school year has significantly increased compared to the first semester of 2020. Also, in the case of Worst 3% or less, the significance probability is 0.000, which is less than 0.05, so the null hypothesis that 'the difference between the two scores is the same' was rejected, indicating that the Worst score for the 2021 school year was significantly higher than that for the first semester of 2020.

• Journal of The Korean Association For Science Education
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• v.41 no.5
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• pp.401-414
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• 2021

The purpose of this study is to explore the cognitive achievement characteristics by group of achievement levels in the PISA 2018 science domain compared to the results of the PISA 2015, and to compare and analyze the 'epistemic' knowledge in the revised curriculum 2009 and in the revised curriculum 2007. The average correctness rates in PISA 2015 and PISA 2018 were analyzed by sub category of the evaluation frame in the PISA scientific domain. In the competencies domain, especially, the average correct answer rates of 'evaluating and designing scientific inquiry' were the lowest in medium and lower groups, but the rates rose in all achievement groups compared to PISA 2015, which is encouraging. Although the answer rates were low for both 'living system' knowledge and 'epistemic' knowledge in the knowledge domain, the average answer rates of the upper and middle groups increased in 'epistemic' knowledge compared to PISA 2015. The changes in the curriculum experienced by students participating in PISA were analyzed in relation to the 'evaluating and designing scientific inquiry' competency and 'epistemic' knowledge, which increased in average correct answer rates. In terms of understanding science, the "What is science?" unit that explicitly presents epistemic knowledge, and nature of model in inquiry activities, were explicitly presented in the revised curriculum 2009. In terms of understanding the process of justifying scientific knowledge, the number of inquiry activities increased, scientific explanations based on experimental results strengthened, and the "Science and Human Civilization" unit was introduced to help students to understand STS while simultaneously conducting arguments. These findings confirm the educational performance of groups by achievement level in the PISA 2018 scientific domain and suggest that the direction of education relates to epistemic knowledge in Korea's Science curriculum.

• Korean Journal of Breeding Science
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• v.49 no.3
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• pp.150-156
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• 2017

This study was carried out to compare the survival and mutation rates and mutation spectrum by gamma-irradiation on rooted and unrooted cuttings of three spray type ('Lovelydia', 'Yellowbabe', and 'Haetsal') and two standard type ('Vital' and 'Aqua') cultivars in roses. Two groups, rooted and unrooted cuttings were gamma-irradiated at 70Gy for 24 hours. The irradiated rooted and unrooted cuttings were planted in a greenhouse, and survival, mutation rates and mutation spectrum were investigated 30 weeks after planting, respectively. As a result, survival and mutation rates of gamma-ray irradiated plants were 16.4%~50.8% and 0~5.1% for unrooted cuttings, and 39.4%~55.1% and 0.7%~7.4% for rooted cuttings, respectively. In conclusion, both survival and mutation rates were a little higher on rooted cuttings than on unrooted cuttings. However, when only survived plants after gamma-ray irradiation were considered, mutation rates were 0~10% and 1.8%~14.1% for unrooted cuttings and rooted cuttings, respectively, showing no significant difference. In addition, diverse variations on color and number of petals or shape of flowers were detected both in plants from rooted and unrooted cuttings, which indicated that there was no significant difference in mutation spectrum between two groups.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.3
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• pp.101-114
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• 2019

In this study, we carry out the numerical simulation to trace the yearly shoreline change of Mang-Bang beach, which is suffering from erosion problem. We obtain the basic equation (One Line Model for shoreline) for the numerical simulation by assuming that the amount of shoreline retreat or advance is balanced by the net influx of longshore and cross-shore sediment into the unit discretized shoreline segment. In doing so, the energy flux model for the longshore sediment transport rate is also evoked. For the case of cross sediment transport, the modified Bailard's model (1981) by Cho and Kim (2019) is utilized. At each time step of the numerical simulation, we adjust a closure depth according to pertinent wave conditions based on the Hallermeier's analytical model (1978) having its roots on the Shield's parameter. Numerical results show that from 2017.4.26 to 2017.10.15 during which swells are prevailing, a shoreline advances due to the sustained supply of cross-shore sediment. It is also shown that a shoreline temporarily retreats due to the erosion by the yearly highest waves sequentially occurring from mid-October to the end of October, and is followed by gradual recovery of shoreline as high waves subdue and swells prevail. It is worth mentioning that great yearly circulation of shoreline completes when a shoreline retreats due to the erosion by the higher waves occurring from mid-March to the end of March. The great yearly circulation of shoreline mentioned above can also be found in the measured locations of shoreline on 2017.4.5, 2017.9.7, 2017.11.7, 2018.3.14. However, numerically simulated amount of shoreline retreat or advance is more significant than the physically measured one, and it should be noted that these discrepancies become more substantial for the case of RUN II where a closure depth is sustained to be as in the most morphology models like the Genesis (Hanson and Kraus, 1989).

• Journal of Korean Society of Disaster and Security
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• v.11 no.2
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• pp.29-35
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• 2018

This study is an experimental comparison on the fact that the sinusoidal load, which has been used so far in the laboratory cyclic test, which is an important part of the liquefaction triggering study, is somewhat different from the phenomenon that causes the soil liquefaction during the earthquake loading. To this end, this study proposes a new type of combined sinusoidal load and compares it with experimental results to load the conventional sine wave. In the comparison, the shaking table tests were carried out and the sample in the tests was remolded with the relative density of 40%, which is a condition where liquefaction is easy to occur. Firstly, the conventional cyclic test was carried out under the condition that with the amplitude of sine wave was 0.3 g. Additionally, 3 types of tests were performed using the combination loads made up with 0.03 g sinusoidal load and 0.3g sinusoidal load. At that time, the loading time for the first sinusoidal load were changed with 5 seconds, 10 seconds, and 15 seconds. As a result, the test with the conventional sine wave and the test with the first sinusoidal loading for 5 seconds showed that the change of the pore water pressure gradually increased. But in the tests with the combined sinusoidal load which changed the first sinusoidal loading time with 10 and 15 seconds, it was found that the pore water pressure suddenly rose at a certain instant and liquefaction occurs. From the experimental comparison, it is judged that it is appropriate that the time of the first sine wave is over 10 seconds at the proposed combined load for the soil condition with relative density 40%.

• Journal of the Korean Applied Science and Technology
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• v.36 no.3
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• pp.915-929
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• 2019

This study attempted to investigate the effects of natural henna-treated permanent wave on degree of damage and morphological changes of hair. For this, amino acid was analyzed, and hair thickness and surface were observed through SEM. In addition, hair curl formation & retention, methylene blue coloring, tensile strength and elongation were measured. The results found the followings: Total amino acid contents rose as the number of natural henna treatment increased, hair protection effects are expected. In terms of curl formation, in an experimental group hair became more elastic as the number of natural henna treatment increased, compared to a control group. In both control and experimental groups, hair retention decreased as shampooing frequency increased because of extension of (C) and (C)', According to analysis of hair thickness using SEM, hair became thick in an experimental group after natural henna treatment, compared to a control group. In morphological observation of hair surface, it was mostly clean, and cuticle was tidy and healthy. In methylene blue coloring, as the number of natural henna treatment increased, absorbance went up. In addition, tensile strength declined in an experimental group, compared to a control group. As the number of natural henna treatment increased, elongation in an experimental group increased, compared to a control group. The above results show that as the number of natural henna treatment increased, hair became thicker, and curl formation and retention improved. In addition, hair elasticity and flexibility were enhanced, reducing a risk of hair damage. Therefore, the study results would be available as basic data in reducing scalp and hair damage, proposing the natural henna treatment as a method to reduce hair damage from chemical perm in cosmetology industry.

• Korean Journal of Ecology and Environment
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• v.52 no.3
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• pp.210-220
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• 2019

Population growth and the increase of energy consumption due to civilization caused global warming. Temperature on the Earth rose about $0.7^{\circ}C$ for the last 100 years, the rate is accelerated since 2000. Temperature is a factor, which determines physiological action, growth and development, survival, etc. of the plant together with light intensity and precipitation. Therefore, it is expected that global warming would affect broadly geographic distribution of the plant as well as structure and function ecosystem. In order to understand the effect of global warming on the ecosystem, a study about the effect of temperature rise on germination and growth in the plant is required necessarily. This study was carried out to investigate the effects of experimental warming on the germination and growth of two oak species(Quercus mongolica and Q. serrata) in temperature gradient chamber(TGC). This study was conducted in control, medium warming treatment($+1.7^{\circ}C$; Tm), and high warming treatment ($+3.2^{\circ}C$; Th) conditions. The final germination percentage, mean germination time and germination rate of two oak species increased by the warming treatment, and the increase in Q. serrata was higher than that in Q. mongolica. Root collar diameter, seedling height, leaf dry weight, stem dry weight, root dry weight, and total biomass were the highest in Tm treatment. Butthey were not significantly different in the Th treatment. In the Th treatment, Q. serrata had significantly higher H/D ratio, S/R ratio, and low root mass ratio (RMR) compared with control plot. Q. mongolica had lower RMR and higher S/R ratio in the Tm and Th treatments compared with control plot. Therefore, growth of Q. mongolica are expected to be more vulnerable to warming than that of Q. serrata. The main findings of this study, species-specific responses to experimental warming, could be applied to predict ecosystem changes from global warming. From the result of this study, we could deduce that temperature rise would increase germination of Q. serrata and Q. mongolica and consequently contribute to increase establishment rate in the early growth stage of the plants. But we have to consider diverse variables to understand properly the effects that global warming influences germination in natural condition. Treatment of global warming in the medium level increased the growth and the biomass of both Q. serrata and Q. mongolica. But the result of treatment in the high level showed different aspects. In particular, Q. mongolica, which grows in cooler zones of higher elevation on mountains or northward in latitude, responded more sensitively. Synthesized the results mentioned above, continuous global warming would function in stable establishment of both plants unfavorably. Compared the responses of both sample plants on temperature rise, Q. serrata increased germination rate more than Q. mongolica and Q. mongolica responded more sensitively than Q. serrata in biomass allocation with the increase of temperature. It was estimated that these results would due to a difference of microclimate originated from the spatial distribution of both plants.

• Korean Association for Visual Culture
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• v.23
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• pp.463-524
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• 2013

En exprimant 'la découverte de l'homme', Valéry, dans la Philosophie de la danse, représente «un plaisir qui allait jusqu'à une sorte d'ivresse, et si intense parfois, qu'un épuisement total de ses forces, une sorte d'extase d'épuisement pouvait seule interrompre son délire, sa dépense motrice exaspérée». Dans le même sens du plaisir, Jayadéva, dans son dithyrambe du Gîta-Govinda, représente la danse de Harî, une des nombreuses formes de Vichnou. Excités par le brûlant désir des jeux de la volupté, Hari et son amante Râdhâ cherchent au cours de la danse Râsa l'énergie vitale. Voilà la source du plaisir mystérieux valéryen. Ensuite l'eau, «élément essentiel de toute vie», est la mesure du temps de même que le soleil, l'eau est le principe de l'harmonie comme celui du monde. Finalement, chez Valéry, sous les diverses infleunces de l'eau mythique, la mer devient l'Océan de lait, soit le lieu de naissance, soit la substance maternelle, soit l'essence da la création universelle. Or tout au long de 「La Dormeuse」, Valéry évoque l'image de 'Vichnou-Narayana' sous l'influence de la mythologie indienne. Et sous une autre influence de Flaubert, Valéry évoque « d'étranges mondes abstraits». Malgré tout, Valéry crée lui-même, dans 「La Dormeuse」, une nouvelle image d'un monde abstrait : 'Vichnou-Narayana' couché sur un lit de lotus, porté par les replis du grand serpent Ananta, qui élève au-dessus du dieu endormi méditant, ses sept têtes formant une éspèce de dais - du sein de Narayana, richement décoré d'un collier d'étoiles et d'une couronne de pierres précieuses en forme de disque, croit un lotus qui porte Brahma dans son calice ; Lakchmi est aux pieds de son divin époux. L'épisode des dieux indiens est à un stade encore plus avancé de la destruction du symbole. Ils sont réduits à des formes symboliques obscures, non commentées et même difficilement identifiables. Le dieu rose qui mord son orteil dans une attitude à la fois mystérieuse et grotesque, c'est Vichnou qui a, selon le vichnouisme, le premier rôle dans la création du monde. Il flottait avant la création sur les eaux, couché sur une feuille de figuier, sous la forme d'un jeune enfant qui porte son pied vers sa bouche. Cette scène évoque la méditation et le repli sur soi de la divinité avant le commencement. Valéry désigne la cosmogonie particulière d'une religion bien déterminée(le vichnouisme) sans la nommer et en la vidant de son sens pouratnt capital, laissant subsister un symbole guetté par le grotesque, un dieu en enfance ; d'autre part, cette cosmogonie est télescopée et intégrée par une cosmogonie d'origine différente : le désemboîtement des trois dieux renvoie à la théorie sivaiste du Lingam, l'arbre de vie. Les dieux de la tirinité iendienne se détachent les un après les autres et il ne reste plus que la fleur sous la garde de Vichnou. Le désemboîtement des dieux paraît bien se référer à cette conception, malgré l'absence du lingam. Enfin toute la forme veille ; et tous les yeux sont ouverts.

• Korean Journal of Legislative Studies
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• v.26 no.2
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• pp.113-140
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• 2020

This study is meaningful in that it is the first analysis of Korean elections using the concept of spatial autocorrelation. Spatial autocorrelation means that an event occurring in one location in space has a high correlation with an event occurring in the surrounding area. The voter turnout rate in the 21^st general election of Seoul area was divided into the early-voting turnout and voting-day turnout, and the spatial pattern of the turnout was examined. Most of the previous studies were based on the unit of the precinct and personal data, but this study analyzed on the basis of the lower unit, Eup-myeon-dong, and analyzed using spatial data and aggregate data. Moran I index showed a fairly high spatial autocorrelation of 0.261 in the voting-day turnout, while the index of the early-voting turnout was low at 0.095, indicating that there was little spatial autocorrelation despite statistical significance. The voting-day turnout, which showed strong spatial autocorrelation, was compared and analyzed using the OLS regression model and the spatial statistics model. In the general regression model, the coefficient of determination R² rose from 0.585261 to 0.656631 in the spatial error model, showing an increase in explanatory power of about 7 percentage points. This means that the spatial statistical model has high explanatory power. The most interesting result is the relationship between the early-voting turnout and the voting-day turnout. The higher the early-voting turnout is, the lower the voting-day turnout is. When the early-voing turnout increases by about 2%, the voting-day turnout drops by about 1%. In this study, the variables affecting the early-voting turnout and the voting-day turnout are very different. This finding is different from the previous researches.

• Journal of the Korean Society of Marine Environment & Safety
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• v.30 no.1
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• pp.13-19
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• 2024

An analysis of the coastal water temperature in the Tongyeong waters, the eastern sea of the South Sea of Korea, revealed that the water temperature rose sharply before the typhoon made landfall. The water temperature rise occurred throughout the entire water column. An analysis of the sea surface temperature data observed by NOAA(National Oceanic and Atmospheric Administration) satellites, indicated that sea water with a temperature of 30℃ existed in the eastern waters of the eastern South Sea of Korea before the typhoon landed. The southeastern sea of Korea is an area where ocean currents prevail from west to east owing to the Tsushima Warm Current. However, an analysis of the satellite data showed that seawater at 30℃ moved from east to west, indicating that it was affected by the Ekman transport caused by the typhoon before landing. In addition, because the eastern waters of the South Sea are not as deep as those of the East Sea, the water temperature of the entire water layer may remain constant owing to vertical mixing caused by the wind. Because the rise in water temperature in each water layer occurred on the same day, the rise in the bottom water temperature can be considered as owing to vertical mixing. Indeed, the southeastern sea of Korea is a sea area where the water temperature can rise rapidly depending on the direction of approach of the typhoon and the location of high temperature formation.