• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.6
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• pp.1092-1099
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• 2022

Research on exhaust aftertreatment devices to reduce air pollutants and greenhouse gas emissions is being actively conducted. However, in the case of the particulate matters/nitrogen oxides (PM/NOx) simultaneous reduction device for ships, the problem of back pressure on the diesel engine and replacement of the filter carrier is occurring. In this study, for the optimal design of the integrated device that can simultaneously reduce PM/NOx, an appropriate standard was presented by studying the flow inside the device and change in back pressure through the inlet/outlet pressure. Ansys Fluent was used to apply porous media conditions to a diesel particulate filter (DPF) and selective catalytic reduction (SCR) by setting porosity to 30%, 40%, 50%, 60%, and 70%. In addition, the ef ect on back pressure was analyzed by applying the inlet velocity according to the engine load to 7.4 m/s, 10.3 m/s, 13.1 m/s, and 26.2 m/s as boundary conditions. As a result of a computational fluid dynamics analysis, the rate of change for back pressure by changing the inlet velocity was greater than when inlet temperature was changed, and the maximum rate of change was 27.4 mbar. This was evaluated as a suitable device for ships of 1800kW because the back pressure in all boundary conditions did not exceed the classification standard of 68mbar.

• Korean Journal of Environment and Ecology
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• v.36 no.3
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• pp.303-317
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• 2022

Climate change caused by increased greenhouse gas emissions can alter the natural ecosystem, including the pollination ecosystem and agricultural ecology, which are ecological interactions between potted insects and plants. Many studies have reported that populations of wild bees, including bees and wasps (BW), which are the key pollinators, have gradually declined due to climate change, leading to adverse impacts on overall biodiversity, ultimately with agribusinesses and the life cycle of flowering plants. Therefore, we could infer that the rising temperature in Korean Peninsula (South Korea) due to global warming has led to climate change and influenced the wild bee's ecosystem. In this study, we surveyed the distributional pattern of BW (Superfamily: Apoidea, Vespoidea, and Chrysidoidea) at 51 sites from 2017 (37 sites) to 2018 (14 sites) to examine the effects of climatic factors on the nationwide distribution of BW in South Korea. Previous literature has confirmed that their distribution according to forest climate zones is significantly correlated with mean and accumulative temperatures. Based on the result, we predicted the effects of future climate changes on the BW distribution that appeared throughout South Korea and the species that appeared in specific climate zones using Shared Socioeconomic Pathways (SSPs). The distributions of wild BW predicted by the SSP scenarios 2-4.5 and 5-8.5 according to the BIOMOD species distribution model revealed that common and endemic species will shift northward from the current habitat distribution by 2050 and 2100, respectively. Our study implies that climate change and its detrimental effect on the ecosystem is ongoing as the BW distribution in South Korea can change, causing the change in the ecosystem in the Korean Peninsula. Therefore, immediate efforts to mitigate greenhouse gas emissions are warranted. We hope the findings of this study can inspire further research on the effects of climate change on pollination services and serve as the reference for making agricultural policy and BW conservation strategy

• Journal of the Korean Wood Science and Technology
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• v.32 no.4
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• pp.8-17
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• 2004

Antifungal, antibacterial, and antioxidative activities of ethanol extracts from 65 families 263 species were investigated to select tree species for the utilization of natural fungicide or preservative resources. The antifungal activities of extracts from wood, leaf and bark were measured as hyphal growth inhibition rate using four plant pathogenic and five wood rotting fungi. High inhibitory effect on the fungi growth was found in five species of Pinaceae (Pinus koraiensis, P. rigida, P. densiflora, P. banksiana. Cedrus deodara), three species of Cupressaceae (Juniperus rigida, J. chinensis, Chamaecyparis obtusa) and three species of Leguminosae (Albizzia julibrisssin, Sophora japonica, Maackia amurensis), respectively. Antibacterial activities of ethanol extracts were determined by means of disc-agar plate diffusion method using three gram-positive and five gram-negative bacteria. The ethanol extracts, which showed prominent effect on the suppression of bacteria growth, were six species of Betulaceae (Carpinus tschonoskii, C. coreana, C. laxiflora, Alnus hirsuta, A. firma, Betula schmidtii), five species of Fagaceae (Castanopsis cuspidata var. sieboldii, Quercus serrata, Q. mongolica, Q aliena, C crenata), four species of Euphorbiaceae (Aleurites fordii, Sapium sebiferum, S japonicum Mallotus japonicus) and three species of Elaeagnaceae (Elaeagnus umbellata, Elaeagnus glanbra, Elaeagnus macrophylla). According to these results, the extracts from Zelkova serrata, Pinus densiflora, Maackia amurensis, Chamaecyparis obtusa and Juniperus chinensis could be available for natural fungicide or food preservatives, because ethanol extracts from these species indicated excellent antifungal and antibacterial activities. In order to test antioxidative activities of ethanol extracts, free radical scavenging method was adopted with 1,1-diphenyl-2-picrylhydrohydrazyl (DPPH). Free radical scavenging activity was proved very high in the extracts of eight species of Rosaceae (Eriobotrya japonica, Prunus takesimensis, P yedoensis, P padus, P armeniaca var. ansu, Chaenomeles sinensis, Stephanandra incisa, Rosa multiflora) and five species of Ericaceae (Rhododenron mucronulatum, R. scblippenbacbii, R. yedoense var. poukhanense, Vaccinium bracteatum, V oldbami), resvectively. It turned out from this study that only six species among 48 species of Rosaceae showed less than 80% free radical scavenging activity. As a consequences, it could be deduced that the components effective on antioxidative activity commonly exist in Rosaceae plant family.

• Korean Association of Arts Management
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• no.58
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• pp.5-47
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• 2021

This paper is a story about five middle-aged men in their 50s who suddenly began their photographic activities as they reached middle age. In the perspective of Borudieu's cultural capital theory, this study observes five men in their 50s by implementing in-depth interviews about the motivation behind taking photographs, the experience of photography activities, and the rewards of these activities. The theory has undergone a theoretical revision with the criticism that factors other than the class can be influential. Based on these ideas, I have proceeded my study by preferentially grasping the notion of the 'field' in accordance with the specific history of Korean society. Therefore, this study sought to more specifically understand the various photographic activities of middle-class men in their 50s by referring Coskuner-Balli and Thompson's argument(2013), which revised 2018's cultural captial theory and proposed the concept of 'subordinate cultural capital' and 'leisure capital' who proposed by Backlund, E. A. & Kuentzel, W. F.(2013). As a middle-class men in their 50s, research participants have grown up and worked in a social atmosphere where economic capital is recognized as an individual's ability. However, they are faced with the value that the knowledge and taste towards culture and arts is one's identity. In addition to the subjective deprivation that arises from this situation, the lifespan characteristic of their age that it is on the brink of the old age appeared to have influenced them to put their psychological motivation immediately into practice. Economic capital was the main conversion terms to move form interest to practice, which includes 'time' as a resource as well as money. With the cultural practices being expanded since their creation of photographs, the reason that these expansions can be maintained more actively lies in their identity as 'cultural artist' that is consolidated in new relationships in the sharing of photographic activities. In this way, photographic activities grant a symbolic status of 'a middle-aged man who actively builds and expresses his identity' through the conversion of accumulating cultural capital and the conversion into social capital. Furthermore, the recognized scope of the symbolic capital acquired by the research participants is in the domain of the private life that is family and acquaintance. Especially, they were gaining a great psychological reward from their children's recognition that they are not just a 'breadwinner' but 'dad who cultivates himself with a culture and arts'. Accordingly, by considering that 'generation' other than class can be a meaningful discussion point when understanding Korea society from the perspective of cultural theory, this study is meaningful that a more flexible understanding of cultural theory can give a glimpse into the possibility of a more specific and diverse approach that will arise in the discussion of culture and arts education.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.6
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• pp.27-36
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• 2021

At a time when the equitable use of urban parks is gradually emerging as a social issue, this study was initiated to expand the influence of urban parks by improving the quality of park services, thereby resolving areas not covered by urban park services. This study targeted the Hangang Park in Seoul, where the qualitative service of parks shows the greatest difference. The influence relationship between the qualitative services of the park and the user's sphere of influence, which indicates the distribution of park users, was proposed to assess the influence of improvements in the quality of service. As a research method, the top three districts and the bottom three districts were selected through the Han River Park user satisfaction survey conducted from 2017 to 2019, and a qualitative service evaluation was carried out. It was derived using the data acquired in September. Afterward, by performing a spatial autocorrelation analysis on the user's sphere of influence, additional verification of the user's sphere of influence was performed numerically and visually. As a result of the study, the user influence in the top three districts, with high-quality service, was stronger and wider than that of the lower three districts. It was confirmed that the quality of service of the park affects the user influence. This shows that to realize park equity, it is necessary to improve the quality of services through continuous management and improvement of individual parks and the creation of new parks. This study has significance in that it recognizes the limitations of research on park services from a supplier's point of view and evaluates the qualitative services of parks from the perspective of actual park users. We propose an alternative to deal with the lower the park deprivation index.

• Journal of Life Science
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• v.33 no.3
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• pp.242-251
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• 2023

The purpose of this study was to investigate the effects of 8-week β-hydroxybutyrate (β-HB) administration with and without endurance exercise training on endurance exercise performance and skeletal muscle protein synthesis and degradation using a mouse model. Forty-eight male wild-type ICR mice (8 weeks old) were randomly divided into four groups: sedentary control (Sed+Con), (Sed+Con), sedentary β-HB (Sed+β-HB), exercise control (Exe+Con), and exercise β-HB (Exe+β-HB). β-HB was dissolved in PBS (150 mg/ml) and injected subcutaneously daily (250 mg/kg) for 8 weeks. Mice performed 5 days/week of a 20 min treadmill running exercise for 8 weeks. The running exercise was carried out at a speed of 10 m/min at a 10° incline for 5 min, and then the speed was increased by 1 m/min for every 1 min of the remaining 15 min. Following 8 weeks of treatments, visceral fat mass and skeletal muscle mass, blood parameters, and the markers for autophagy and protein synthesis were analyzed. The data were analyzed with one-way ANOVA (p<0.05) using the SPSS 21 program. Eight weeks of Exe+β-HB treatment significantly lowered blood lactate levels compared with the other three groups (Sed+Con, Sed+β-HB, and Exe+β-HB) Exe+β-HB) (p<0.05). Eight weeks of Exe+β-HB significantly increased maximal running time (time to exhaustion) compared with the Sed+Con and Exe+Con groups (p<0.05). Eight weeks of β-HB administration significantly decreased autophagy flux and autophagy-related proteins in the skeletal muscle of mice (p<0.05). Conversely, the combined treatment of β-HB and endurance exercise training increased protein synthesis (mTOR signaling and translation) (p<0.05). The 8-week β-HB treatment and endurance exercise training had synergistic effects on the increase in endurance performance, increase in protein synthesis, and decrease in protein degradation in the skeletal muscle of mice.

• Geophysics and Geophysical Exploration
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• v.26 no.1
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• pp.18-30
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• 2023

Submarine mud volcanos are topographic features that resemble volcanoes, and are formed due to eruptions of fluidized or gasified sediment material. They have gained attention as a source of subsurface heat, sediment, or hydrocarbons supplied to the surface. In the continental slope of the Canadian Beaufort Sea, mud volcano exists at various water depths. The MV420, is an active mud volcano erupting at a water depth of 420 meters, and it has been the subject of extensive study. The Korea Polar Research Institute(KOPRI) collected high-resolution seismic data and heat flow data around the caldera of the mud volcano. By analyzing the multi-channel seismic data, we confirmed the reverse-polarity reflector assumed by a gas hydrate-related bottom simulating reflector(BSR). To further elucidate the relationship between the BSR and gas hydrates, as well as the thermal structure of the mud volcano, a numerical geothermal model was developed based on the steady-state heat equation. Using this model, we estimated the base of the gas hydrate stability zone and found that the BSR depth estimated by multi-channel seismic data and the bottom of the gas hydrate stability zone were in good agreement., This suggests the presence of gas hydrates, and it was determined that the depth of the gas hydrate was likely up to 50 m, depending on the distance from the mud conduit. Thus, this depth estimate slightly differs from previous studies.

• Journal of the Daesoon Academy of Sciences
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• v.29
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• pp.171-207
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• 2017

The research regarding religious concepts used in Daesoon Jinrihoe are still incomplete. This study is a suggestion to critically review the existing research on 'seeking out the original root (原始返本)', one of the religious terms of Daesoon Jinrihoe. In addition, this concept will be seen from a new perspective. 'Seeking out the original root' plays a major role in Daesoon theology due to the cosmology established by Daesoon Jinrihoe. However, the existing research on this topic are prone to the perspective of 'returning' and assuming a 'cyclical view on the order of history'. Therefore, the cosmology that has been built by the religious language misleads readers to assume a retrospective process or that the process itself is realized on its own in accordance with the cosmic order. These kinds of studies do not specifically manifest the world view of Daesoon Jinrihoe. They fail to do so because Sangje's reordering works and its fruit, the earthly paradise of the Later World, have never existed before. The concept of 'seeking out the original root' should break away from the frame of a cyclical view of history and exert the uniqueness of Daesoon Jinrihoe. In this regard, this study can be summarized as follows: 'Seeking out the original root', one of the principles needed to achieve the re-creation of the Later World, endeavors to find a way to account for the origin of all things such as civilizations, cultures, and dharmas. If such a way is found, the facts between the root and the beginning should be acknowledged, as the root itself is what has been sustained, succeeded, used, resolved, revised, and rectified. The origin is usually dealt with from the position of rewarding. This was all achieved in Sangje's decisions and his reordering works. Its outcome will be utilized as a basis to establish an earthly paradise in the Later World. This concept, as defined above, excludes a cyclical view of history and implies that the concept of 'seeking out the original root' is a flexible frame within the context of dynamic structuralism. Given the style of this approach, this study provides a view which can be easily differentiated from existing research.

• (The) Research of the performance art and culture
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• no.41
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• pp.257-284
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• 2020

Goseong Ogwangdae started academic research in the late 1950s and was designated as a national intangible cultural asset in 1964. From the time of the academic survey to the time of designation, it was recorded as using paper masks, but when the recording image was filmed in 1965, it was already changed to wooden masks. In 1960, before being designated as an intangible cultural asset, the number of masks, which was 9 points, gradually increased to 19 points in 1964. It is necessarily included in the leper, Chorani, Malttuki, Cheongbo-Yangyang, Halmi, and Jemilju, but the character of the yangban is not yet clearly differentiated. Hwangbongsa and Sangju appeared as bare faces, and consumption, milling, Cheongbo-Yangyang are used together with Bibi and inspiration. It can be guessed that Bibi was not the appearance of a foreign object with horns as it is now, considering that Bibi and Madangsoi were used together. Since 1965, shortly after the designation, the whole of the Goseong Ogwangdae mask has been changed to a wooden mask. All the characters except for resident, courtyard, and top-of-the-line are wearing masks. Bibi, Hongbaek, and service masks have never appeared until 1964. The Yangban was changed to the closing ceremony with six people in the order of Won-Yangban, Baekje, Heukje, Cheongje, Hongbaek, and Jonggadoryong. Starting in 1969, the mask enters the stable period where the kind is the same as the present. Bibi-Yangban uses both the Won-Yangban and the Jemilju uses the Somu, but all other characters use the individual mask to use a total of 18 masks. The Yangbans are clearly differentiated, and a total of seven Yangban appear. The reason why the change in the type of mask and the expression of material is so large is that the first generation of mask makers died and the tradition of mask production was cut off, but there is also a cause of the extreme change in the environment of the drama that the performers who joined after the designation had to face. Also, it is closely related to the change of the times when the meaning and weight of masking in masking has changed. At that time, the performers were not so tied to the current concept of 'original form' that they preserved the appearance of the designated time. Originally, Goseong Ogwangdae was centered on improvisation dance, not the formalized dance as it is now, and there was a certain fluid aspect in the retelling, so it was flexible in the use of masks even before the designation of cultural assets. Strict rules did not apply in the details, as it was a self-sufficient play by the performers, not an offer event. The form and contents of this fluid play are changed to preparation for the performance while preparing for the folk art contest. As the subject of the contest in self-sufficient play, dance, costumes, and props became more and more colorful as well as dancing, costumes, and props. As a result, participation in the contest brought about changes in the overall performance and changed the mask, which was accepted within the preservation society.

• Journal of Popular Narrative
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• v.25 no.1
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• pp.349-392
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• 2019

In the 1960s of Korea, the normalization of diplomatic relations between Korea and Japan led to a sense of a vigorous anxiety and fear that "Japan will once again come to the Korean peninsula". As a reaction to this, the discourse on the criticism of 'Japanese Style' strongly emerged. If the prior discourse of criticism was to express the national antipathy toward the colonial remnants that had not yet been disposed of, the critical discourse of the 1960s was the wariness of the newly created 'Japanese Style' in popular culture, and to grasp it as a symptomatic phenomenon that 'evil-minded Japan' was revealed. Thus, this new logic of criticism of the 'Japanese Style' had a qualitative difference from the existing ones. It was accompanied by a willingness to inspect and censor the 'masses' that grew up as consumers of transnational 'mass culture' that flowed and chained in the geopolitical order under the Cold War system. Therefore, the topology of 'popular things=Japanese things=consuming things' reveals the paradox of moral demands that existed within Korean society in the 1960s. This was to solidify the divisive circulation structure that caused them to avoid direct contact with the other called 'Japan', but at the same time, get as close to it as ever. It is a repetitive obsession that pushes the other to another side through the moral segregation that strictly draws a line of demarcation between oneself and the other, but on the other hand is attracted to the object and pulls it back to its side. This paper intends to listen to the different voices that have arisen in the repetitive obsession to understand the significance of the dissonance that has been repeated in the contemporary era. This will be an examination of the paradoxical object of Japan that has been repeatedly asked to build the internal control principle of Korean society, or to hide the oppressive and violent side of the power, and that can neither be accepted nor destroyed completely as part of oneself.