• Clean Technology
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• v.25 no.3
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• pp.179-188
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• 2019

Upon the combustion of coal particles in a coal-fired power plant, fly ash (80%) and bottom ash (20%) are unavoidably produced. Most of the ashes are, however, just dumped onto a landfill site. When the landfill site that takes the fly ash and bottom ash is saturated, further operation of the coal-fired power plant might be discontinued unless a new alternative landfill site is prepared. In this study, wet flotation separation system (floating process) was employed in order to recover unburned carbon (UC), ceramic microsphere (CM) and cleaned ash (CA), all of which serving as useful components within fly ash. The average recovered fractions of UC, CM, and CA from fly ash were 92.10, 75.75, and 69.71, respectively, while the recovered fractions of UC were higher than those of CM and CA by 16% and 22%, respectively. The combustible component (CC) within the recovered UC possessed a weight percentage as high as 52.54wt%, whereas the burning heat of UC was estimated to be $4,232kcal\;kg^{-1}$. As more carbon-containing UC is recovered from fly ash, UC is expected to be used successfully as an industrial fuel. Owing to the effects of pH, more efficient chemical separations of CM and CA, rather than UC, were obtained. The average $SiO_2$ contents within the separated CM and CA had a value of 53.55wt% and 78.66wt%, respectively, which is indicative of their plausible future application as industrial materials in many fields.

• The Korean Journal of Archival Studies
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• no.45
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• pp.121-153
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• 2015

Struggles to gain acknowledgement of identity have a characteristic of movement to recover human dignity. Participants in this movement come to confirm themselves as the subject of rights and communicate one another, free from oppression. Being guaranteed the opportunity to participate in the public opinion formation process is an indispensable element of human rights. In 1980, though it was short and incomplete, Gwangju experienced communal autonomy under the condition that state power was temporarily stopped. The contents and memories of the Gwangju Democratization Movement that intended to protect autonomy of civil society, resisting pillage of state power, remain intact in the 1980 Archives for the May 18th. The 5.18 archives were registered in UNESCO's Memory of the World in 2011, with its value of human rights and protection of democracy being acknowledged. The 5.18 archives have memories of resistance and struggles for justice, and sacrifices and pains of citizens under oppressive political authority in Gwangju, 1980. Thus, these archives are related to the historical struggles for democracy, and suggest a lesson on the transition process towards democracy to us. Preservation and utilization of the documentary heritage constantly lead the memories of historical events to the present, and enable exchanges of experiences and ideas between the present and the future. This study, through the process of UNESCO's Memory of the World registration and post-registration process, beyond the value of archives, tries to examine how historical events are led to the present, through the archives and to discuss the other values of archives.

• Journal of the Korean Data Analysis Society
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• v.20 no.6
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• pp.3117-3126
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• 2018

The operating system update is a basic step to maintain a safe internet use environment. This study analyzed whether the implementation of the operating system update was related to gender and age group during the violation accident prevention act in relation to information protection on the internet, and tried to verify the validity of these factors by analyzing the influence of gender and age group. In this study, logistic regression analysis was conducted based on the information security survey data surveyed by the Korea Internet & Security Agency in 2016. As a result, gender and age were surveyed as factors related to the implementation of operating system updates. As a result of analyzing the impact on the implementation of operating system updates by gender, it is estimated that the odds are 0.419 times higher for women than for men. According to the analysis of the operating system update by age group based on the 50s, which is a vulnerable group of information, the result is that the odds are 13.266 times higher in the 20s than the 50s.

• Journal of Food Hygiene and Safety
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• v.36 no.4
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• pp.342-346
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• 2021

Cold brew coffee extracted from cold water for a long time has drawn public concern over hygiene. This study was carried out to investigate the microbiological contamination levels and caffeine contents in cold brew coffee. A total of 75 cold brew coffees were purchased from offline and online sources. As a result, the average number of bacteria in samples purchased online was 1.14 log CFU/mL (0-6.57 log CFU/mL), while bacteria were not detected in samples purchased offline. Therefore, stricter surveys are required to avoid the food contamination. However, Esherichia coli and nine types of foodborne pathogens were not detected in all samples. The average caffeine content of the samples was 1.6 mg/mL (384 mg/240 mL), so the caffeine almost reached to acceptable daily intake levels (400 mg for adults). However, ten products did not provide any precautions for consumer safety, so improvement of the system is needed. This monitoring data can contribute to the protection of consumer rights and improvement in the safety of cold brew coffee.

• International Area Studies Review
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• v.13 no.2
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• pp.573-600
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• 2009

Currently, the Free Trade Agreement(FTA) promoting regionalism or bilateralism has been increasingly concluded, which is against multilateralism of the WTO. The adoption of the TRS under the FTA carries various issues from the rationale of its existence to its contents. To explain these contradictory issues between the WTO and the FTA, this paper studied on the TRS by analyzing present cases and negotiation results of the TRS under the FTA and comparing them under the WTO. The TRS under the WTO agreement is limited only to antidumping, countervailing duties and safeguard as the agreed concept. When the negotiations of the FTA are on the process, it is necessary to adopt the TRS depending on the negotiating party countries of the FTA after considering fully the economic situations of Korea and the need of protection for the domestic industries. Currently, Korea has entered into the FTA with several countries and most of the agreements with respect to the TRS maintain and observe the right and duty in the WTO agreement and when necessary, in some of the FTA agreements, they have changed parts of the TRS. Consequently, it is needed to establish the basis for application of the TRS. Also, additional application of the SSG provision to some sensitive goods is highly recommended.

• The Journal of Korean Philosophical History
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• no.43
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• pp.33-53
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• 2014

It's the situation that modern technological civilization shakes the life environment fundamentally without a serious reflection on the dangers. The sense of crisis' brought the rise of modern Ecology in awareness of survivability of the humanity. Because the serious reflection is not just a campaign for environmental protection, but is to establish the values which is possible to coexist and to make harmony between the nature and man, man and man, and to form a healthy relationship through philosophical thought and practice has intrinsic value for human and nature. Under these circumstances, if Yulgok lives now and he is questioned by the ecological theorists of the 21st century that "What do you think about the serious environmental problem of present times?", what really would be his explanation? In the presentation methods of the explanation, will question first what contents western ecologists who study Theory of the environment in technology, Deep Ecology, and Social Ecology propose, then will compare and introduce what similarities and differences from theirs. As a result, we'll be found that Yulgok's thought, moral consciousness, about the nature and humanity as a confucian scholar.

• Journal of Digital Convergence
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• v.19 no.3
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• pp.453-463
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• 2021

The purpose of this study is to establish the most severe impacts of Covid-19 in the field of the performing arts and to explore countermeasures taken both at home and abroad. This study has been conducted through literature surveys. The conclusion is as follows. First, since the outbreak of Covid-19, theater venues around the world have actively taken part in uploading recorded performances to streaming services. Secondly, these performance visualizings are generally considered as being complimentary goods rather than a substitute for live performance. Thirdly, although more audiences are tuning into watch on-line performances, consumption is concentrated on a few theaters which have a worldwide reputation and a broad range of content. Fourthly, to tackle the impact that Covid-19, the UK government announced a series of job protection schemes in the field of the Arts. In addition, Arts Council England prepared an emergency response package. In Korea, some countermeasures such as government support for artists and cultural establishments have also been implemented. Lastly, some suggestions for the sector. I conclude that there is an need for domestic companies to secure core contents of significant quality and to make strategic alliances with leading overseas performance companies so that they may cooperate together.

• Journal of the Korea Convergence Society
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• v.12 no.8
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• pp.229-243
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• 2021

As systematic information protection and management is recognized as an organization's core value, organizations are pursuing a shift from an individual-centered information management method to an organization-oriented information management method. The Enterprise content management system(ECMS) is a solution that supports document security and information sharing by insiders and is being introduced by many organizations due to recent technological developments. The purpose of this study is to present a method of improving performance through continuous use of the ECMS from the user's point of view and also suggest a method to improve the intention of continuous use through the expansion of the technology acceptance model. This study surveyed the employees of organizations that adopted the ECMS and verified the research hypothesis derived from previous studies through structural equation modeling. As a result of the analysis, usefulness, and ease of use affected on the intention of continuous use of the ECMS, and the knowledge sharing culture and the ECMS quality factors affected the technology acceptance model factors. The results of this study have academic and practical significance in terms of suggesting a plan to increase the usability of the ECMS from the user's point of view.

• Journal of Digital Convergence
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• v.20 no.5
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• pp.261-268
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• 2022

This study tried to understand the meaning of resource attraction, entertainment experience, love mark, and attachment of tourist destinations. A theoretical study was conducted on each research concept to achieve the proposed research purpose. Based on this, an empirical study was conducted after deriving a questionnaire based on this, and a non-face-to-face survey was conducted nationwide using population-proportional sampling. The empirical study was confirmed through the statistical programs SPSS25.0 and AMOS25.0. The resource attractiveness of the tourist destination had a positive (+) relationship with the influence on the tourists' experience. The relationship between the experience and the love mark had a positive (+) relationship. A positive (+) relationship was also formed in the relationship between experience and attachment. However, the relationship between love mark and attachment did not form a significant relationship.Because it reflects regional characteristics, it is a useful material for local culture and history, so protection, preservation, and active program development are required. is needed.

• Journal of Life Science
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• v.33 no.1
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• pp.43-49
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• 2023

Houttuynia cordata belongs to the Saururacease family and its leaves, stems, and roots have been used as oriental medicines to treat pneumonia, acute or chronic bronchitis, enteritis, and abscesses and to remove extravasated blood. Recently, the antioxidant, anti-inflammation, antibacterial, and anti-proliferation activities and protection abilities of H. cordata against liver and neuron cell damage have been reported. In this study, ethanol extract and its solvent fractions (fractions of hexane, ethyl acetate, butanol, and water residue) were prepared, and their antithrombosis, antidiabetes, antioxidant, and hemolysis activities were evaluated. The ethyl-acetate fraction of H. cordata (EF-HC) showed the highest polyphenol and flavonoids contents among the fractions and exhibited strong antithrombosis and antioxidant activities. The EF-HC at 5 mg/ml showed 2.09-folds of thrombin time, 2.19-folds of prothrombin time, and 1.69-folds of activated partial thromboplastin time compared to the their solvent control and 30.9, 19.9, and 49.6 ㎍/ml of RC₅₀ against DPPH, ABTS, and nitrite radicals, respectively. Furthermore, the EF-HC did not show any hemolytic activity up to 1 mg/ml, whereas the hexane fraction of H. cordata showed 55% hemolysis at 1 mg/ml. This is the first report of the antithrombosis activity of H. cordata. Our results suggest that quercitirin, hyperoside, orientin, and isoquercitrin in EF-HC are related to its antithrombosis and antioxidant activities and that the EF-HC could be developed as a promising antithrombosis agent.