• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.131-131
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• 2013

A single-layer graphene has been uniformly grown on a Cu surface at elevated temperatures by thermally processing a poly(methyl methacrylate) (PMMA) film in a rapid thermal annealing (RTA) system under vacuum. The detailed chemistry of the transition from solid-state carbon to graphene on the catalytic Cu surface was investigated by performing in-situ residual gas analysis while PMMA/Cu-foil samples being heated, in conjunction with interrupted growth studies to reconstruct ex-situ the heating process. The data clearly show that the formation of graphene occurs with hydrocarbon molecules vaporized from PMMA, such as methane and/or methyl radicals, as precursors rather than by the direct graphitization of solid-state carbon. We also found that the temperature for vaporizing hydrocarbon molecules from PMMA and the length of time the gaseous hydrocarbon atmosphere is maintained, which are dependent on both the heating temperature profile and the amount of a solid carbon feedstock are the dominant factors to determine the crystalline quality of the resulting graphene film. Under optimal growth conditions, the PMMA-derived graphene was found to have a carrier (hole) mobility as high as ~2,700 cm2V-1s-1 at room temperature, superior to common graphene converted from solid carbon.

• Korean Journal of Ecology and Environment
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• v.49 no.4
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• pp.375-384
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• 2016

Phytoplankton community is one of the important factors for the management of aquatic environment due to generation of varying toxins by harmful algal species. This study was performed to examine the phytoplankton community structure (PCS) in the midstream of Geum River (GR) from January 2014 to December 2015. The water sampling was performed in five stations on 2014, and three stations on 2015. Subsequently, the morphological identification was performed by microscopic observation in laboratory condition. As results, total 265 species were identified and it was comprised of 40.8% of Bacillariophyceae, 9.1% of Cyanophyceae, 44.5% of Chlorophyceae, and the others (4.9%). During the investigation period, total average standing crop of phytoplankton was $12,948cells\;mL^{-1}$, and it was comprised of $7,702cells\;mL^{-1}$ of Bacillariophyceae, $2,821cells\;mL^{-1}$ of Cyanophyceae, $2,121cells\;mL^{-1}$ of Chlorophyceae, and $305cells\;mL^{-1}$ of others. To verify which tributaries of upstream area influence on PCS of midstream of GR, the phytoplankton standing crops of two stations including Mihocheon (MH) and Gapcheon (GC) were examined on 2014, and compared to result of on 2015. The results were shown that the MH station had more similar phytoplankton standing crops with midstream of GR than GC station. The relationship between environmental parameters and phytoplankton dynamics was studied at the investigated station. As results, whereas water temperature and total phosphorus were represented the positive correlation, N/P ratio was remarkably exhibited negative correlation. From the results, it is suggested that the PCS of midstream of GR was more affected by MH station than GC station, and the changes of temperature, phosphorus concentration, and N/P ratio may be important factors on the PCS formation of midstream of GR.

• Korean Journal of Remote Sensing
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• v.15 no.2
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• pp.175-181
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• 1999

A recurring eddy which located at the terminal end of the Korean East Warm Current was captured on ocean color and sea surface temperature imagery from satellite in spring and autumn. During late April, 1997 thermal infrared imagery from the NOAA AVHRR sensor and ocean color data from the Japanese ADEOS-I OCTS sensor, revealed this feature. The cold core had elevated chlorophyll concentrations, based on OCTS estimates, of greater than 3 mg/m$^3$ while the warmer surrounding waters had chlorophyll concentrations of 1 mg/m$^3$ or less. The elevated cholophyll accociated with this eddy has not been previously described. The eddy is also evident in SST images from autumn, but the SST in the core is warmer than in spring, and the warm jet flowing to the west of the eddy is also warmer is autumn compared to spring. A reccurring eddy and the high chlorophyll_a concentration area which surround around the eddy show on NOAA and SeaWiFS images in March 2, 1998. The eddy forms at the northern extent of the Korean East Warm Current as those waters collide with the cold, south-flowing Liman Current over a topographic shelf about 1500 m deep. This region of the eddy formation appears to have a strong connection with the dynamics of the western part of the polar front eddy field that dominates surface mesoscale structure in the central East (Japan) Sea. Interaction of the eddy with ARGOW tracked drifters, and evidence for its persistence are discussed.

• Korean Journal of Remote Sensing
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• v.23 no.6
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• pp.567-573
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• 2007

Tidal channel development is influenced by sediment type, grain size, composition and tidal current. Tidal channels are usually characterized by channel formation, density and shape. Quantitative analysis of tidal channels using remotely sensed data have rarely been studied. The objective of this study is to quantify tidal channels in terms of fractal dimension and compare different inter-tidal channel patterns and compare with DEM (Digital Elevation Model). For the fractal analysis, we used box counting method which had been successfully applied to streams, coastlines and others linear features. For a study, the southern part of Ganghwado tidal flats was selected which know for high dynamics of tidal currents and vast tidal flats. This area has different widths and lengths of tidal channels. IKONOS was used for extracting tidal channels, and the box counting method was applied to obtain fractal dimensions (D) for each tidal channel. Yeochari area where channels showed less dense development and low DEM had low fractal dimenwion near $1.00{\sim}1.20$. Area (near Donggumdo and Yeongjongdo) of dendritic channel pattern and high DEM resulted in high fractal dimension near $1.20{\sim}1.35$. The difference of fractal dimensions according to channel development in tidal flats is relatively large enough to use as an index for tidal channel classification. Therefore we could conclude that fractal dimension, channel development and DEM in tidal channel has high correlation. Using fractal dimension, channel development and DEM, it would be possible to quantify the tidal channel development in association with surface characteristics.

• Korean Journal of Comparative Education
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• v.28 no.3
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• pp.291-307
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• 2018

As the value of lifelong learning becomes important, states are making efforts to build a system of lifelong learning. According to this tendency, this paper intends to compare the participation rate of lifelong learning, learning outcomes, learning support infrastructure, support of learning expenses, and recognition of lifelong learning. For the comparative pedagogical approach, Bray and Thomas' cubes such as geographical / regional level, non - geographical demographic statistics, social and educational aspects were utilized. The participation rate of lifelong learning in Korea is 34.4% in 2017, which is lower than the OECD average of 46%. The competency scores of Korean adults were lower than the OECD national averages of the PIAAC survey which measured adult competence, language ability, numeracy, and computer-based problem solving ability. In order to recognize prior learning, EU countries have developed EQFs to evaluate all non-formal and informal learning outcomes, while Korea recognizes qualification as a credit banking credit under the academic credit banking system. International comparisons of lifelong learning can be used as an important tool for diagnosing the actual conditions of lifelong learning in a country and establishing future lifelong learning policies. Therefore, it is necessary to maintain that the comparative pedagogical approach of lifelong learning differs according to the historical context, socioeconomic characteristics, and population dynamics, including the formation process and characteristics of modern countries.

• Nuclear Engineering and Technology
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• v.53 no.1
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• pp.61-68
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• 2021

Experiments of vertically upward steam-water two-phase flow have been carried out in single-side heated narrow rectangular channel with a gap of 3 mm. Flow patterns were identified and classified through visualization directly. Slug flow was only observed at 0.2 MPa but replaced by block-bubble flow at 1.0 MPa. Flow pattern maps at the pressure of 0.2 MPa and 1.0 MPa were plotted and the difference was analyzed. The experimental data has been compared with other flow pattern maps and transition criteria. The results show reasonable agreement with Hosler's, while a wide discrepancy is observed when compared with air-water two-phase experimental data. Current criteria developed based on air-water experiments poorly predict bubble-slug flow transition due to the different formation and growth of bubbles. This work is significant for researches on heat transfer, bubble dynamics and flow instability.

• Ocean and Polar Research
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• v.44 no.4
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• pp.269-285
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• 2022

The interaction between ocean and ice shelf is a critical physical process in relation to water mass transformations and ice shelf melting/freezing at the ocean-ice interface. However, it remains challenging to thoroughly understand the process due to a lack of observational data with respect to ice shelf cavities. This is the first study to simulate the variability and circulation of water mass both overlying the continental shelf and underneath an ice shelf and an ice tongue in the Terra Nova Bay (TNB), East Antarctica. To explore the properties of water mass and circulation patterns in the TNB and the corresponding effects on sub ice shelf basal melting, we explicitly incorporate the dynamic-thermodynamic processes acting on the ice shelf in the Regional Ocean Modeling System. The simulated water mass formation and circulation in the TNB region agree well with previous studies. The model results show that the TNB circulation is dominated by the geostrophic currents driven by lateral density gradients induced by the releasing of brine or freshwater at the polynya of the TNB. Meanwhile, the circulation dynamics in the cavity under the Nansen Ice shelf (NIS) are different from those in the TNB. The gravity-driven bottom current induced by High Salinity Shelf Water (HSSW) formed at the TNB polynya flows towards the grounding line, and the buoyance-driven flow associated with glacial meltwater generated by the HSSW emerges from the cavity along the ice base. Both current systems compose the thermohaline overturning circulation in the NIS cavity. This study estimates the NIS basal melting rate to be 0.98 m/a, which is comparable to the previously observed melt rate. However, the melting rate shows a significant variation in space and time.

• The Journal of Korean Philosophical History
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• no.27
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• pp.145-166
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• 2009

This paper analyzes the views of Gyeongjae O Chiik on Classical Studies. O is the second son of Noju O Heesang (1763-1833). The characteristics of his views are as follows. First, unlike his father, Gyeongjae is more interested in Chinese Textual Criticism than in Hsing-li hsüeh. Therefore, he provides textual interpretation in detail with erudition in his Manrok and Munjip on the formation and problems for such classics as The Four Classics, The Classic of Poetry, The Book of Changes, The Rites of Zhou, The Book of Rites, and The Spring and Autumn Annals. Second, his openness. He didn't canonize The Book of Changes. Also, he thought that the analysis of Jeongja in his Annotation on the Book of Changes and Zhuxi's Original Interpretations, the absolute authority of the time, were not the only interpretation possible. He argued that other interpretation is possible depending on perspectives and it is desirable. We can see that Gyeongjae had transcended the world view of Zhuxi Studies. Third. he put the emphasis on the theories during the Han dynasty. He showed the inclination toward the Yuheung theories rather than Zhuxi theories in regard of the discussion of names in The Analects of Confucius. Fourth, unlike other Confucius scholars in Chosun, he showed interests in Gongyangjeon and Gokryangjeon. He compiled Gonggokmunseon with beautiful writings from both works. Fifth, he was interested in the dynamics of constant numbers. He grasped that what is important in the Book of Changes is not right principles but constant numbers and points. Thus he compiled Sangjeomyuhoe. Besides, he was also interested in the Rites of Zhou.

• The Journal of the Convergence on Culture Technology
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• v.8 no.3
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• pp.399-404
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• 2022

Céline Sciamma is a leading female director of her time. She is constantly making works on the subject of women. It can be said that it has pioneered a 'female narrative'. In particular, it shows a unique perspective in dealing with the complexities surrounding the formation of a girl's sexual identity and the influence of peer culture on individuals. In Portrait of a Lady on Fire, 'The Handmaiden', 'The Painter', and 'The Maid' show the solidarity of women without hierarchies in a liberated space where the patriarch is absent, showing a feminist interpretation of classics and a self-reflecting consciousness of women's historical records. Based on the setting of drawing, this film explores the genderization of gaze, gaze and objectification, issues of seeing and power, etc. constructed throughout the history of visual arts. The portrait work of Heloise and Marianne in the film deconstructs the formula of 'a male painter as a viewer and a female model who gazes at herself through the male gaze' and turns the gaze into an interactive process of giving and receiving. The process of exchanging gazes is sealed with a nude painting in which Marianne's face is superimposed on Heloise's body. This overturns the nude painting as the dominant form of engraving the male audience's position in the image through the stylization of the viewing method in the history of Western painting with the erotic gaze of a lesbian in an instant.

• Analyses & Alternatives
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• v.2 no.1
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• pp.5-29
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• 2018

Models of South-North Korean economic integration have the problem of circular reasoning. While many studies argue that South-North Korean economic integration would contribute to alleviate security risks in the Korean peninsular, they emphasize the success of any economic model of inter-Korean economic integration is subject to favorable geo-political and security environment. It is a failure in distinguishing between goals and constraints. After identifying three major goals of South-North Korean economic cooperation, this study shows the trilemma among the goals; they are 1) formation of a complete economic community, 2) maintaining independent sovereignty of the two Koreas, 3) promotion of mutual economic interests. The trilemma suggests that it is theoretically impossible to achieve the above three goals at the same time. Only two goals are achievable simultaneously. This study argues that the most practical option is to pursue the combination of goals 2) and 3) considering the complex political and security environment around the Korean peninsular. Recognizing that North Korea is the least developed country in the Northeast Asia region, South Korea's initiatives for inter-Korean economic cooperation should focus on assisting industrialization and integration of the North Korea economy into the Northeast Asian regional production sharing structure. In view of the 'flying geese model' of the sequential industrialization in the region, the least developed economic status of North Korea can partially be explained by its failure to participate in the production network in the region as well as lack of effective implementation of appropriate industrial policy. Therefore, promotion of industrialization of North Korea should be the immediate goal of economic cooperation between North and South Korea. It is an interesting fact that North Korea has rapidly expanded its apparel exports in recent years. It could mean that the North Korean economy is actively responding to the dynamics of international comparative advantage structure, although the production activities are limited to exports to China since the closure of the Gaesung Industrial Complex. The recent increase in apparel export is a starting point for incorporating the Easy Import Substitution fulfilling both domestic and neighboring regional demand of North Korea. It could help integrate North Korea's industry into the production network of Northeast Asia. An immediate policy implication is that the economic cooperation between the two Koreas should focus on facilitating this process and supporting North Korea's industrial policy through South Korea's contribution of capital, technology, and service intermediary inputs.