• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.4
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• pp.438-444
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• 2018

Korea has recently selected twenty-two ports for reinforcement breakwater installation of protection facilities, due to rise sea level caused by global warming and increase in the number of typhoon and tsunami. In addition, due to consistent enlargement of ship size, dredging for depth of water for large vessel's berthing and enlargement of berth is under construction. However, no definite construction plan for the reinforcement and lengthening of crown height, which has close relationship with the safe mooring of ships. In this study, domestic and foreign design criteria of crown height were analyzed, and the crown height evaluation index and evaluation method were developed by dividing it into environment and ship elements. In particular, in the case of ship evaluation index, each step was set up in 4 steps according to domestic and foreign regulations, weighted by each step, and the safety level of crown height was evaluated. As a result of the mooring safety simulation of the 100,000 ton cruise ship, the appropriate minimum crown height standard was derived to be 3 m above A.H.H.W. The results of this study are expected to be used as basic data to propose the crown height standard reflecting ship characteristics.

• Composites Research
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• v.34 no.5
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• pp.290-295
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• 2021

The application of lightweight structural composites to automobiles as a solution in line with global fuel economy regulations to curb global warming is recognized as a megatrend. This study was conducted to provide a technical approach that can respond to the issue of replacing parts that require conductive properties to maximize the application of thermoplastic carbon fiber reinforced plastics (CFRPs), which are advantageous in terms of repair, disposal and recycling. By utilizing the properties of the low-viscosity polymerizable oligomer matrix, it was possible to prepare a thermoplastic CFRP exhibiting excellent impregnation properties while uniformly mixing the conductive filler. Various carbon-based conductive fillers such as carbon black, carbon nanotubes, graphene nanoplatelets, graphite, and pitch-based carbon fibers were filled up to the maximum content, and electrical and thermal conductive properties of the fabricated composites were compared and studied. It was confirmed that the maximum incorporation of filler was the most important factor to control the conductive properties of the composites rather than the type or shape of the conductive carbon filler. Experimental results were observed in which it might be advantageous to apply a one-dimensional conductive carbon filler to improve electrical conductivity, whereas it might be advantageous to apply a two-dimensional conductive carbon filler to improve thermal conductivity. The results of this study can provide potential insight into the optimization of structural design for controlling the conductive properties of thermoplastic CFRPs.

• Journal of the Korea Convergence Society
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• v.9 no.11
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• pp.417-424
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• 2018

The purpose of this study was to examine how combined exercise and acaiberry intake make effects on insulin and glycated hemoglobin of middle-aged women. The middle-aged women in their 40s and 50s were classified into three groups - group A which only had acaiberry intake, group B which both had acaiberry intake and combined exercise, and group C which only underwent the combined exercise. The combined exercise was held three times a week for 8 weeks, each for 60 minutes including warming up and cooling down. The aerobic exercise was carried out for 20 minutes with a treadmill walk with HRmax 50-60% and the resistance movement was carried out for 20 minutes with a strength of 50-60% based on 1RM. The participants were told to have the acaiberry drink before breakfast and dinner, by melting 5g of acaiberry powder to water. 2-way RGRM ANOVA was carried out to process the data for comparing each groups. In conclusion, the 8-weeks of combined exercise and acaiberry ingestion therapy did not improve the insulin and glycated hemoglobin. It is more likely to show clear changes in both elements with longer treatments and controlling the amount of ingestion and exercise intensity.

• Clean Technology
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• v.25 no.1
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• pp.63-73
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• 2019

Numerical analysis was done to evaluate the chemical reaction and the reduction rate inside of selective non-catalytic reduction to denitrification in combustion process. The $NO_X$ reduction in selective non-catalytic reduction is converted to not only nitrogen but also nitrous oxide. Simultaneous $NO_X$ reduction and nitrous oxide generation suppressing is required in selective non-catalytic reduction because nitrous oxide influences the global warming as a greenhouse gas. The current study was performed compare the computational analysis in the same temperature and amount of NaOH, and in comparison with the previous research experiments and confirmed the reliability of the computational fluid dynamics. Additionally, controlling the addition amount of NaOH to predict the $NO_X$ reduction efficiency and nitrous oxide production. Numerical analysis was done to check the mass fraction of each material in the measurement point at the end of selective non-catalytic reduction. Experimental Value and simulation value by numerical analysis showed an error of up to 18.9% was confirmed that a generally well predicted. and it was confirmed that the widened temperature range of more than 70% $NO_X$ removal rate is increased when the addition amount of NaOH. So, large and frequent changes of the reaction temperature waste incineration facilities are expected to be effective.

• Journal of the Korean earth science society
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• v.42 no.6
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• pp.717-733
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• 2021

This study is aimed to provide basic data to set the direction of polar literacy education and to raise awareness of the importance of polar research. Elementary, middle, and high school students' perception of the polar region was examined in terms of current status of polar information, impression regarding polar regions, and awareness of related issues. The study included 975 students from nine elementary, middle, and high schools, who responded to 16 questions, including close-ended and open-ended items. The results suggest that students had more experiences regarding the polar region on audiovisual media, but relatively limited learning experiences in school education. The impression they had of the polar region was confined to the monotonous image of a polar bear in crisis, following the melting of the glacier due to global warming. The students formed powerful images by combining scenes they saw in audiovisual media with emotions. In terms of recognizing problems in the polar region, the students were generally interested in creatures, natural environment, and climate change, but their interests varied depending on their school level and their own career path. The students highly valued the scientist's status as agents to address the problems facing the region, and gave priority to global citizenship values rather than practical standards. Based on the results, we suggest the following: introducing and systematizing content focusing on the polar region in the school curriculum, providing a differentiated learning experience through cooperation between scientists and educators, establishing polar literacy based on concepts that are relevant to various subjects, earth system-centered learning approach, setting the direction for follow-up studies and the need for science education that incorporates diverse values.

• Journal of Animal Science and Technology
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• v.65 no.2
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• pp.324-335
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• 2023

Korea, located in East Asia in the northern hemisphere, is experiencing severe climate changes. Specifically, the heat stress caused by global warming is negatively affecting the dairy sector, including milk production and reproductive performance, as the major dairy cattle Holstein-Friesian is particularly susceptible to heat stress. Here, we collected artificial insemination and pregnancy data of the Holstein and the Jersey cows from a dairy farm from 2014 to 2021 and analyzed the association between the conception rate and the temperature-humidity index, calculated using the data from the closest official weather station. As the temperature-humidity index threshold increased, the conception rate gradually decreased. However, this decrease was steeper in the Holstein breed than in the Jersey one at a temperature-humidity index threshold of 75. To evaluate the effects of heat stress on the oocyte quality, we examined the nuclear and cytoplasmic maturation of Holstein (n = 158, obtained from six animals) and Jersey oocytes (n = 123, obtained from six animals), obtained by ovum pick-up. There were no differences in the nuclear maturation between the different conditions (heat stress: 40.5℃, non- heat stress: 37.5℃) or breeds, although the Holstein oocytes seemed to have a lower metaphase II development (p = 0.0521) after in vitro maturation under heat stress conditions. However, we found that the Holstein metaphase II oocytes exposed to heat stress presented more reactive oxygen species and a peripheral distribution of the mitochondria, compared to those of the Jersey cattle. Here, we show that weather information from local meteorological stations can be used to calculate the temperature-humidity index threshold at which heat stress influences the conception rate, and that the Jersey cows are more tolerant to heat stress in terms of their conception rate at a temperature-humidity index over 75. The lower fertility of the Holstein cows is likely attributed to impaired cytoplasmic maturation induced by heat stress. Thus, the Jersey cows can be a good breed for the sustainability of dairy farms for addressing climate changes in South Korea, as they are more resistant to hyperthermia.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.25-25
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• 2022

Drought becomes frequent and severe because of continuous global warming, leading to a significant loss of crop yield. In soybean (Glycine max [L.]), most of quantitative trait loci (QTLs) analyses for drought tolerance have conducted by investigating yield changes under water-restricted conditions at the reproductive stages. More recently, the necessity of QTL studies to use physiological indices responding to drought at the early growth stages besides the reproductive ones has arisen due to the unpredictable and prevalent occurrence of drought throughout the soybean growing season. In this study, we thus identified QTLs conferring wilting scores and moisture contents of soybean subjected to drought stress in the early vegetative stage using an recombinant inbred line (RIL) population derived from a cross between Taekwang (drought-sensitive) and SS2-2 (drought-tolerant). For the two traits, the same major QTL was located on chromosome 10, accounting for up to 11.5% of phenotypic variance explained with LOD score of 12.5. This QTL overlaps with a reported QTL for the limited transpiration trait in soybean and harbors an ortholog of the Arabidopsis ABA and drought-induced RING-D UF1117 gene. Meanwhile, one of important features of plant drought tolerance is their ability to limit transpiration rates under high vapor pressure deficiency in response to mitigate water loss. However, monitoring their transpiration rates is time-consuming and laborious. Therefore, only a few population-level studies regarding transpiration rates under the drought condition have been reported so far. Via employing an Arduino-based platform, for the reasons addressed, we are measuring and recording total pot weights of soybean plants every hour from the 1^st day after water restriction to the days when the half of the RILs exhibited permanent tissue damage in at least one trifoliate. Gradual decrease in moisture of soil in pots as time passes refers increase in the severity of drought stress. By tracking changes in the total pot weights of soybean plants, we will infer transpiration rates of the mapping parents and their RILs according to different levels of VPD and drought stress. The profile of transpiration rates from different levels of severity in the stresses facilitates a better understanding of relationship between transpiration-related features, such as limited maximum transpiration rates, to water saving performances, as well as those to other drought-responsive phenotypes. Our findings will provide primary insights on drought tolerance mechanisms in soybean and useful resources for improvement of soybean varieties tolerant to drought stress.

• Korean Journal of Ecology and Environment
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• v.46 no.2
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• pp.289-300
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• 2013

Forest vegetation of Hyangjeokbong (1,614 m) in Deogyusan National Park is classified into mountain forest vegetation and flatland forest vegetation. Mountain forest vegetation is subdivided into deciduous broad-leaved forest, valley forest, coniferous forest, subalpine coniferous forest, shrub forest, grassland forest, afforestation and etc., while riparian forest was found under the category of flatland forest vegetation. Including 122 communities of mountain forest vegetation and 2 communities of riparian forest, the total of 124 communities were researched; the distributed colonies classified by physiognomy classification are 42 communities deciduous broad-leaved forest, 37 communities of valley forest, 8 communities of coniferous forests, 6 communities of subalpine coniferous forest, 3 communities of shrub forest, 1 communities of grassland forest, 21 afforestation and 4 other communities. As for the distribution rate for surveyed main communities, Quercus mongolica, Quercus serrata, Quercus variabilis communities account for 47.02 percent of deciduous broad-leaved forest, Fraxinus mandshurica community takes up 57.48 percent of mountain valley forest, Pinus densiflora community holds 77.53 percent of mountain coniferous forest holds, and Taxus cuspidate-Abies koreana community takes up about 50 percent of subalpine coniferous forest. Mountain shrub forest and mountain grassland forest vegetation are concentrated mainly on the top of Hyangjeokbong and the ridge connecting the top and Jungbong. Meanwhile, riparian forest vegetation comprises 0.024% of the whole vegetation area in a study area. In conclusion, minority species consisting of Quercus mongolica, Quercus serrata, Quercus variabilis, Fraxinus mandshurica, Cornus controversa, Pinus densiflora, Abies koreana and Taxus cuspidata are distributed as dominant species of the uppermost part in a forest vegetation region in Deogyusan National Park. In addition, because of vegetation succession and climate factors, numerous colonies formed by the two species are expected to be replaced by Quercus mongolica, Carpinus laxiflora and Fraxinus mandshurica which are climax species in the area. However, in respect of subalpine coniferous forest, the distribution rate of deciduous broad-leaved forest seems to increase gradually due to global warming and artificial disturbance.

• Korean journal of applied entomology
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• v.55 no.1
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• pp.17-26
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• 2016

Climate change has been regarded as one of main factors to change Korean insect pest fauna. Especially, a global warming model predicts to expand habitat for insect pests originated from tropical or subtropical regions. Two insect pests, the beet armyworm (Spodoptera exigua) and the diamondback moth (Plutella xylostella), are known to overwinter in some greenhouse conditions without diapause induction in Korea. There was a clear difference between these two insects in seasonal occurrence. P. xylostella occurred only at early spring and fall seasons, but did not occur during summer. In contrast, S. exigua maintained their occurrence from late spring to fall seasons. This study set up a hypothesis that the difference in the seasonal occurrence may be resulted from variation in susceptibility to high temperature. To test the hypothesis, heat tolerance was compared between these two insects. Exposure to $42^{\circ}C$ for 40 min killed 100% individuals of P. xylostella larvae. However, most larvae of S. exigua survived in response to $42^{\circ}C$ even for 80 min. Heat tolerance varied among developmental stages in both insects. Highest tolerant stages were $4^{th}$ instar larvae and adults for P. xylostella, but $1^{st}$ instar larvae for S. exigua. Pre-exposure to $37^{\circ}C$ for 30 min significantly increased heat tolerance in both insects. Induction of heat tolerance accompanied with significant increase of glycerol contents in the hemolymph in both insects and up-regulation of three heat shock protein expressions in S. exigua. These results suggest that the differential susceptibility to high temperature explains the disappearance of P. xylostella during summer, at which S. exigua maintains its occurrence.

• The Journal of Art Theory & Practice
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• no.14
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• pp.53-83
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• 2012

This thesis is a study of artistic measures and climate refugees, based on Hack's World Climate Refugee Camp project. According to Hack, climate refugees appeared with the process of globalization. Hack claimed that the people who put climate refugees in danger are the industrialized nations, and therefore, their rejection of refugees is nonsense. He also stated that the fundamental solution would be the active participation of such nations. Thus, he travels around the world, encouraging participants and globalizing his project. Interestingly, the practical participation method of his climate calamity project is divided into four methods, which are all related to realizing the danger and presenting various solutions. First, the aesthetic of survival: the reason Hack focused on the warming trend and claimed that we have to accept the climate refugees as refugees comes from the thought that we are all potential refugees, and the anxiety that climate refugees may cause war in the end. The solution Hack found for surviving in such a world is to create "refugee camps" to notify people about the seriousness of climate change, and to put the "aesthetic for survival" in action. Second, a relation-oriented relationship: communication between Hack and the participants was done in various ways. They are experiencing a bond and emotions of an interrelationship through their actions in the experimental field, experiencing a new form of art, which they were not able to experience in a museum. Third, a utopian measure: Hack's utopian measure started from the fear of dystopia but Hack still believes that it is not only a dream, but that it can be realized. He claims that even though the start may be feeble, it is possible to rescue children from starvation and to treat climate refugees as proper human in the end, when communication and cooperation is done the right way and properly. Fourth, the aesthetic of global relation, the internet: the new solution Hack is trying on the internet is to make more people participate in his project. It is fate that "human are the wrongdoer and the victim at the same time", but according to Hack's opinion, social disaster can be avoided through effort and it is optimistic that we can give form to the culture revolution we are experiencing now. Hack's project illustrated the importance of daily life, compared to art inside a museum, through active participation of the people and opened up a new method of art through realistic responses to disasters. This is distinctive from the past exhibitions, where artists gave shape and form to ideals and an imaginary world, in that it shows that the artist and audience aim for creating a community-like structure, just like Bourriaud's art method. Hack's project of climate calamity illustrates that installation and action art is not only an art genre which shows installation and activities, but that it can include social and political issues and that it can be completed with the help of participants, consequently becoming a genre of modern art. Hack raises a question about art's identity through various descriptions. Artists as planners, who base their artworks on their subjectivity or the characteristics of a specific period, the people as participants, the duet of art work and play, human and human, and further, human and nature. The practical participation method, as a measure for "disaster", reveals the new art of the 21st century within Hack's artworks. Even though there are several problems with Hack's usage of art as a measure for disaster, it will actively open up a new page for the 21st century's art with the theme of disaster.