• Clean Technology
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• v.28 no.4
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• pp.269-277
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• 2022

With the recent development of the biological enzymatic reaction industry, lactic acid (LA) can be mass-produced from biomass sources. In particular, a catalytic process that converts LA into acrylic acid (AA) is receiving much attention because AA is used widely in the petrochemical industry as a monomer for superabsorbent polymers (SAP) and as an adhesive for displays. In the LA conversion process, NaY zeolites have been previously shown to be a high-activity catalyst, which improves AA selectivity and long-term stability. However, NaY zeolites suffer from fast deactivation due to severe coking. Therefore, the aim of this study is to modify the acid-base properties of the NaY zeolite to address this shortcoming. First, base promoters, Ca ions, were introduced to the NaY zeolites to tune their acidity and basicity via ion exchange (IE) and incipient wetness impregnation (IWI). The IWI method showed superior catalyst selectivity and stability compared to the IE method, maintaining a high AA yield of approximately 40% during the 16 h reaction. Based on the NH₃- and CO₂-TPD results, the calcium salts that impregnated into the NaY zeolites were proposed to exit as an oxide form mainly at the exterior surface of NaY and act as additional base sites to promote the dehydration of LA to AA. The NaY zeolites were further treated with KOH before calcium impregnation to reduce the total acidity and improve the dispersion of calcium through the mesopores formed by KOH-induced desilication. However, this KOH treatment did not lead to enhanced AA selectivity. Finally, calcium loading was increased from 1wt% to 5wt% to maximize the amount of base sites. The increased basicity improved the AA selectivity substantially to 65% at 100% conversion while maintaining high activity during a 24 h reaction. Our results suggest that controlling the basicity of the catalyst is key to obtaining high AA selectivity and high catalyst stability.

• Journal of the Korea Organic Resources Recycling Association
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• v.30 no.2
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• pp.17-28
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• 2022

The application of supplemental activated biochar pellet fertilizers (ABPFs) was evaluated by investigating key factors such as changes of surface paddy water and soil chemical properties and rice growth responses during the growing season. The treatments consisted of control, activated rice hull biochar pellet (ARHBP-40%), and activated palm biochar pellet (APBP-40%) applications. It was shown that the lowest NH₄⁺-N and PO₄^--P concentrations were observed in surface paddy water to the ARHBP-40%, while the NH₄⁺-N concentration in the control was abruptly decreased until 30 days after transplant in the soil. However, the lowest NH₄⁺-N concentration in the blended biochar application was 9.18 mg L^-1 at 1 day of transplant, but its ABPFs application was observed to be less than 1 mg L^-1 at 56 days after transplant. The lowest PO₄^--P concentration in paddy water treated ARHBP-40% ranged from 0.06 mg L^-1 to 0.08 mg L^-1 until 30 days after transplant among the treatments. For the paddy soil, the NH₄⁺-N concentration in the control was abruptly decreased from 177.7 mg kg^-1 to 49.4 mg kg^-1, while NO₃^--N concentration was highest, 13.2 mg kg^-1 in 14 days after transplant. The P₂O₅ concentrations in the soils increased from rice transplants until the harvesting period regardless of the treatments. The highest K₂O concentration was 252.8 mg kg^-1 in the APBP-40% at 84 days after transplant. For the rice growth responses, plant height in the control was relatively high compared to others, but grain yield was not significantly different between the control and ARHBP-40%. The application of ARHBP-40% can minimize nitrogen and phosphorous application rates into the agro-ecosystem.

• 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

• MISULJARYO - National Museum of Korea Art Journal
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• v.100
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• pp.82-110
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• 2021

This study specifically examined the date of the black glazed bowls marked with "Gongyu (供御)" or "Jinzhan (進琖)" of Jian ware, one of the key research topics related to the bowls. The results of this study can be summarized as follows. Jian Kiln produced various shapes of black glazed bowls, but almost all of the inscriptions of "Gongyu (供御)" or "Jinzhan (進琖)" are found only in two certain type bowls: Type I, the Shukou type bowls (束口碗), or Type II, the Piekou type bowls (撇口碗). Of these, there are significantly more of the former in existence. For Type I bowls marked with "Gongyu (供御)" or "Jinzhan (進琖)", the mouth of the bowls is slightly evaginated outwards, and the inclination angle of the side slope is about 50°. The shape feature, Shukou (束口) is formed which is slightly indented around the bowl about 0.3~0.5cm below the mouth of bowl. And the height of the bowls is relatively low compared to other Type I black glazed bowls produced by Jian Kiln, so the height divided by the diameter is 0.5 or less. There is little difference in shape between the black glazed bowls marked with "Gongyu (供御) and those with "Jinzhan (進琖)". However, taking into consideration the excavation situation of both type bowls, the former is considered to be ahead of the latter in terms of production date. On the other hand, the black glazed bowls of Jian ware, which have the same shape features as the Type I bowls marked with "Gongyu (供御)" or "Jinzhan (進琖)" have not been found in the tombs dating from the end of the 12th to the beginning of the 13th century from which typical Jian kiln black glazed bowls of the same type were excavated. For the Hakata site (博多遺址) in Japan, the black glazed bowls with such a shape feature were excavated from early 12th century sites, rather than from the late 12th to early 13th century sites at which the typical black glazed bowls of Jian kiln were found. Considering that the black glazed bowls from Fujian province were imported into Hakata with almost no time gap, it is very unlikely that the production time of Type I black glazed bowls marked with "Gongyu (供御)" or "Jinzhan (進琖)" will deviate from the early 12th century. In conclusion, it is considered that the black glazed bowls marked with "Gongyu (供御)" or "Jinzhan (進琖)" of Jian ware were produced in the early 12th century.

• Science of Emotion and Sensibility
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• v.25 no.1
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• pp.3-20
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• 2022

Recently, prior to the commercialization of urban air mobility (UAM), the importance of R&D for air transportation-related industries in urban areas has significantly increased. To create a UAM environment, research is being conducted on personal air vehicles (PAVs). They are key means of air transportation, but research on the physical factors influencing their passengers is relatively insufficient. In particular, because the PAV is expected to be used as a living space for the passengers, research on the effects of the physical elements generated in the PAV on the human body is essential to design an interior space that supports the in-vehicle activities of the passengers. Therefore, the purpose of this study is to derive the constraint factors that affect the human body due to the air navigation characteristics of the PAV and to understand the impact of these constraint factors on the bodies of the passengers performing in-vehicle activities. The results of this study indicate that when the PAV was operated at less than 4,000 ft, which is the operating standard, the constraint factors were noise, vibration, and motion sickness caused by low-frequency motion. These constraint factors affect in-vehicle activity; thus, the in-vehicle activities that can be performed in a PAV were derived using autonomous cars, airplanes, and PAV concept cases. Furthermore, considering the impact of the constraint factors and their levels on the human body, recommended constraint factor criteria to support in-vehicle activities were established. To reduce the level of impact of the constraint factors on the human body and to support in-vehicle activity, the seat's shape and built-in functions of the seat (vibration reduction function, temperature control, LED lighting, etc.) and external noise reduction using a directional speaker for each individual seat were recommended. Moreover, it was suggested that interior materials for noise and vibration reduction should be used in the design of the interior space. The contributions of this study are the determination of the constraint factors affecting the in-vehicle PAV activity and the confirmation of the level of impact of the factors on the human body; in the future, these findings can be used as basic data for suitable PAV interior design.

• Journal of the Korea Institute of Building Construction
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• v.22 no.5
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• pp.473-483
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• 2022

BIM(Building Information Modeling) is a technology that can manage information throughout the entire life cycle of the construction industry and serves as a platform for improving productivity and integrating the entire construction industry. Currently, BIM is actively applied in developed countries, and its use at various overseas construction sites is increasing This is unclear. due to air shortening and budget savings. However, there is still a lack of institutional basis and technical limitations in the domestic construction sector, which have led to the lack of utilization of BIM. Various activation measures and institutional frameworks will need to be established for the early establishment of these productive BIMs in Korea. Therefore, as part of the research for the domestic settlement and revitalization of BIM, this study derived a number of key factors necessary for the development of the construction industry through brainstorming and expert surveys using AHP techniques and analyzed the relative importance of each factor. In addition, prior surveys by a group of experts resulted in 1, 3 items in level, 2, 9 items in level, and 3, 27 items in level, and priorities analysis was performed through pairwise comparisons. As a result of the AHP analysis, it was found that the relative importance weight of policy aspects was highest in level 1, and the policy factors in level 2 and the cost-based and incentive system introduction factors were considered most important in level 3. These findings show that the importance of the policy guidance or institutions underlying the activation of BIM rather than research and development or corporate innovation is relatively high, and that the preparation of policy plans by public institutions should be the first priority. Therefore, it is considered that the development of a policy system or guideline must be prioritized before it can be advanced to the next activation stage. The use of BIM technologies will not only contribute to improving the productivity of the construction industry, but also to the overall development of the industry and the growth of the construction industry. It is expected that the results of this study can provide as useful information when establishing policies for activating BIM in central government, relevant local governments, and related public institutions.

• Journal of Christian Education in Korea
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• v.68
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• pp.375-415
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• 2021

Although the interest in Christian education of spirituality has increased recently, the practice of the education of spirituality in the Korean Church has been fragmented in the contents and methods without any clear educational purpose of the Protestant tradition. This requires a creative study to seek out the contents and method best suited to realizing the educational purpose of the Protestant tradition, through a rigorous academic methodology. This study proposes just such a creative model for the education of spirituality with an educational purpose based on the core ethos of the Protestant spirituality, integrating the long tradition of spiritual practices of Christianity. First, I survey the teachings on 'the life of faith' of the main leaders of the Protestant church, including Martin Luther, John Calvin, and John Wesley. Through this process, I reveal 'liberated-ness' to be the common purpose of the Protestant leaders, and the core of the practices for that purpose are 'the means of grace,' which has a different meaning from that of the Roman Catholic tradition. I construct the meaning of 'liberated-ness' in a dynamic manner, which begins with the 'liberating will' of God, and is followed by the 'self-giving will' of the believer as the response to the 'grace' of the 'liberating will.' The contact point of these two 'wills' is what I call 'the living membrane of faith.' As a creative synthesis of the above discussions, I propose a model of 'the practice of liberated-ness' for an education in spiritual practice. The purpose of this education is for the learner to become a person who continuously experiences ever-increasing 'liberated-ness' through continuous personal 'encounters' with God, and to become ever more faithful in carrying out practices for the 'liberated-ness' of her or his neighbors. The relationship between the teacher and the learner is that of personal 'encounter' as put forth by Sherrill, and also incorporates elements of 'co-authorship' as conceptualized by Kim. I transform and rename major practices of spiritual discipline according to a principle of 'liberated-ness' based on the Protestant tradition, and these comprise the main content of my spirituality education model. They include: 'lectio divina of encounter,' 'prayer facing the Lord,' 'service in liberation,' 'reflection of liberated-ness,' and 'mutual spiritual direction.' The teaching and learning process draws on Dykstra's methods of coaching and mentoring. The key environment is that of a 'sacramental community' as defined by Moore. Evaluation can be performed only by the learner her/himself. The significance of this model is that it creatively inherits and succeeds the tradition of Christian spiritual discipline from the early church onwards by transforming it through a Protestant spirituality of 'liberated-ness.'

• Ecology and Resilient Infrastructure
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• v.9 no.3
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• pp.163-173
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• 2022

Climate change is a key factor that greatly influences changes in the biological seasons and geographical distribution of species. In the ecological field, the BioClimatic predictor (BioClim), which is most related to the physiological characteristics of organisms, is used for vulnerability assessment. However, BioClim values are not provided other than the future period climate average values for each GCM for the Shared Socio-economic Pathways (SSPs) scenario. In this study, BioClim data suitable for domestic conditions was produced using 1 km resolution SSPs scenario detailed data produced by Rural Development Administration, and based on the data, a species distribution model was applied to mainly grow in southern, Gyeongsangbuk-do, Gangwon-do and humid regions. Appropriate habitat distributions were predicted every 30 years for the base years (1981 - 2010) and future years (2011 - 2100) of the Acer pictum subsp. mono. Acer pictum subsp. mono appearance data were collected from a total of 819 points through the national natural environment survey data. In order to improve the performance of the MaxEnt model, the parameters of the model (LQH-1.5) were optimized, and 7 detailed biolicm indices and 5 topographical indices were applied to the MaxEnt model. Drainage, Annual Precipitation (Bio12), and Slope significantly contributed to the distribution of Acer pictum subsp. mono in Korea. As a result of reflecting the growth characteristics that favor moist and fertile soil, the influence of climatic factors was not significant. Accordingly, in the base year, the suitable habitat for a high level of Acer pictum subsp. mono is 3.41% of the area of Korea, and in the near future (2011 - 2040) and far future (2071 - 2100), SSP1-2.6 accounts for 0.01% and 0.02%, gradually decreasing. However, in SSP5-8.5, it was 0.01% and 0.72%, respectively, showing a tendency to decrease in the near future compared to the base year, but to gradually increase toward the far future. This study confirms the future distribution of vegetation that is more easily adapted to climate change, and has significance as a basic study that can be used for future forest restoration of climate change-adapted species.

• Analyses & Alternatives
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• v.6 no.2
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• pp.79-115
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• 2022

This study aims to account for electoral choice in the 2020 presidential election by focusing on social identity which forms the basis for core partisan groups. Two views compete to explain the origins of polarization, policy versus party. One emphasizes policy as more influential in choosing presidential candidates. This follows the tradition of retrospective voting theory in which voters' choice rely on government performance. Incumbent president whose performance proves well are rewarded to be reelected. Policy performance is based on measures around distinctive preferences for government spending. Republican Individuals prefer individual responsibility to government support, while Democratic counterparts support government support. Another perspective put an emphasis on the role partisanship which favors in-party members and disfavors partisan out-groups. Interparty animosity plays the key role in determining electoral behavior. This study relies on the Views of the Electorate Research (VOTER) Survey which provides a panel data of several waves from 2011 to 2020. A comparative evaluation of two views highlights three findings. First, policy matters. Policy preferences of voters are the primary drives of political behavior. Electoral outcomes in 2020 turned out to be the results of policy considerations of voters. 53.7 percent of voters tilted toward individual responsibility voted for Trump, whereas 70.4 percent of those favorable views of government support than individual responsibility voted for Biden. Thus effects of policy correspond to a positive difference of 26.4 percent points. Second, partisanship effects are of similar extent in influencing electoral choice of candidates: Democrats are less likely to vote for Trump by 42.4 percent points, while Republicans are less likely to vote for Biden by 48.7 percent points. Third, animosity of Republicans toward Democrat core groups creates 26.5 percent points of favoring Trump over Biden. Democrat animosity toward Republican core groups creates a positive difference of 13.7 percent points of favoring Biden.

• Journal of Christian Education in Korea
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• v.70
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• pp.37-74
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• 2022

COVID-19, which occurred in Wuhan, China, made it difficult for Korean churches to face to face worship, therefore metaverse emerged as an alternative to solving these problems. metaverse is forming various platforms through technology expressed in 3I(Immersion, Interactive, virtual Image). The purpose of this study is to analyze the application plan of Christian education by applying metaverse technologies to Christian education. In order to achieve the purpose of this study, first, the definition, type, platform, and technology of the metaverse are presented to examine the key of the metaverse, second, in order to analyze the church from the theological educational aspect, the essence of the church, the mission of the church, and the metaverse church are examined, third in order to apply the metaverse to Christian education, it is classified into worship through the metaverse, education through the metaverse, service through the metaverse, the christian relationship through the metaverse, and missions through the metaverse. The application plan of the metaverse for Christian education is that first, worship can be held through metaverse. Second, education can be performed through the metaverse. Third, the metaverse can be used to fulfill the mission of service. Fourth, through the metaverse, christian can fellowship through the metaverse. Fifth, the missionary mission can be carried out through the metaverse. In conclusion, metaverse is still in the development stage, but various programs should be developed to achieve the purpose of Christian education by utilizing various platforms developed so far and utilizing the advantages of the platform. In particular, the Korean church will be able to utilize various programs such as Sunday worship, Sunday school, youth retreat, QT, Bible school, and pilgrimage through the metaverse to make good use of the characteristics of the metaverse. In addition, metaverse is an extended reality(XR) that integrates VR, AR, and MR, and its strength is an engagement in creative Christian educational activities out of the original Christian education. In the future, metaverse technology can be applied to Christian education in various ways as the fourth industrial technology is developing.