• Clean Technology
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• v.27 no.1
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• pp.24-32
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• 2021

Unburned carbon (UC) was successfully separated from fly ash by up to 85.8% in weight via froth flotation using soybean oil as a collector. An 18 wt% yield of microceramics (CM) could be achieved by employing a hydro cyclone separator located immediately after the flotation equipment. UC and CM were tested as alternatives to weight-adding material and polymer (especially polypropylene in this study) filler, respectively. Large particles of UC were broken down into smaller ones via ball milling to have an average particle diameter of 10.2 ㎛. When crushed UC was used as an alternative to clay as a rubber weight-adding material, a somewhat lower tensile strength and elongation rate than the allowed values were unfortunately obtained. In order to satisfy the standard limits, further treatment of UC is required to enhance surface energy for more intimate bonding with rubber. CM was observed in spherical forms with an average diameter of 5 ㎛. The surface of the CM particles was modified with phenol, polyol, stearic acid, and oleic acid so that the surface modified CM could be used as a polypropylene-filling agent. The flowability was good, but due to the lack of coupling forces with polypropylene, successful impact strength and flexural strength could not be obtained. However, when mixing the surface-modified CM with 1% silane by weight, a drastic increase in both the impact strength and flexural strength were obtained.

• Journal of the Korea Convergence Society
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• v.12 no.8
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• pp.105-113
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• 2021

Due to the recent coronavirus outbreak, many universities in Korea have started to implement remote education. Accordingly, the Ministry of Education has stated its plans to continuously encourage and maintain remote learning as the future innovation model for education and suggested the need for a diverse range of remote learning models. However, studies on the development of practical learning models have not been carried out actively until now. Particularly, there are not many case studies in the field of design, especially regarding mobile website development. As means to improve the newly designed practice environment, this study therefore proposes the "modoo" project that offers domain creation and online marketing services. As a result of this study, the researcher suggests the use of a mixed(blending) teaching method and realized that the effectiveness of education multiplies when project-based learning and flipped learning is combined appropriately. The research methodology was divided into two big sections, education content and operations, and the effect was evaluated using the course evaluations. The study results confirmed that the applicability will increase given that learning satisfaction levels increased by more than 5% compared to face-to-face learning.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.27 no.3
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• pp.129-139
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• 2021

We studied the consumer preference for the packaging of "Samgyetang" retort product in order to improve its function and design. A total of 319 eligible respondents (male 175, female 144) were surveyed with a questionnaire asking on the general characteristics for the preference of the packaging function, type of retort package, packaging design, convenience, cooking method of retort product and characteristics of "Samgyetang" retort product. The collected data was analyzed using a chi-square (X²) statistical test in SPSS program. The results showed that the retort packages with opacity and microwaveable types were preferred. Also, most respondents expressed that it needs to be improved for cooking convenience. Another question results showed that the consumers are considering the taste and cost of a product more important than the brand of its product when purchasing. Based on the results of the questionnaire, the study suggested that many consumers want the convenience of packaging and product protection for high value added product. The results help to provide consumer's demand for packaging development and to provide the greatest advantages in terms of production and marketability of "Samgyetang" retort product.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.39 no.6
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• pp.541-548
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• 2021

Recently, multispectral cameras are being actively utilized in various application fields such as agriculture, forest management, coastal environment monitoring, and so on, particularly onboard UAV's. Resultant multispectral images are typically georeferenced primarily based on the onboard GPS (Global Positioning System) and IMU (Inertial Measurement Unit)or accurate positional information of the pixels, or could be integrated with ground control points that are directly measured on the ground. However, due to the high cost of establishing GCP's prior to the georeferencing or for inaccessible areas, it is often required to derive the positions without such reference information. This study aims to provide a means to improve the georeferencing performance of a multispectral camera images without involving such ground reference points, but instead with the simultaneously onboard high resolution RGB camera. The exterior orientation parameters of the drone camera are first estimated through the bundle adjustment, and compared with the reference values derived with the GCP's. The results showed that the incorporation of the images from a high resolution RGB camera greatly improved both the exterior orientation estimation and the georeferencing of the multispectral camera. Additionally, an evaluation performed on the direction estimation from a ground point to the sensor showed that inclusion of RGB images can reduce the angle errors more by one order.

• The Journal of the Korea Contents Association
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• v.22 no.7
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• pp.55-62
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• 2022

The perovskite solar cell is an active part of research in renewable energy fields such as solar energy, wind, hydroelectric power, marine energy, bioenergy, and hydrogen energy to replace fossil fuels such as oil, coal, and natural gas, which will gradually disappear as power demand increases due to the increase in use of the Internet of Things and Virtual environments due to the 4th industrial revolution. The perovskite solar cell is a solar cell device using an organic-inorganic hybrid material having a perovskite structure, and has advantages of replacing existing silicon solar cells with high efficiency, low cost solutions, and low temperature processes. In order to optimize the light absorption layer thin film predicted by the existing empirical method, reliability must be verified through device characteristics evaluation. However, since it costs a lot to evaluate the characteristics of the light-absorbing layer thin film device, the number of tests is limited. In order to solve this problem, the development and applicability of a clear and valid model using machine learning or artificial intelligence model as an auxiliary means for optimizing the light absorption layer thin film are considered infinite. In this study, to estimate the light absorption layer thin-film optimization of perovskite solar cells, the regression models of the support vector machine's linear kernel, R.B.F kernel, polynomial kernel, and sigmoid kernel were compared to verify the accuracy difference for each kernel function.

• Journal of Korea Entertainment Industry Association
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• v.15 no.4
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• pp.157-166
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• 2021

The purpose of this study is to understand the characteristics of contemporary vocalization and songs in order to learn various vocal methods in musical vocal classes and apply them to students. Musical vocalization methods change and evolve according to the demands of the times. Today, the characteristics of contemporary musicals cannot be limited to anyone genre, and the genre of music as well as the style of work are derived from several genres and coexist. 'The Girl in 14G,' the subject of this study, is a song that appeared in the album of Kristin Chenoweth, a famous American musical actress who uses various vocal techniques. Jeanine Tesori composed this song with various vocal techniques such as Classical, Jazz, Belting, and Mixed Voice to express New York's representative music genres of Broadway Musical, Metropolitan Opera and East Village Jazz. The development of the song consists of a difficult process in which one actor has to act across three different characters in three musical styles and singing methods. Singing 'The Girl in 14G' requires a lot of effort and practice as it is necessary to acquire various vocal techniques, which makes it a good text for students and actors in the educational perspective. As a result, this study confirmed that this song is a representative piece with a solid musical and dramatic composition and is a good example that shows the convergence characteristics of contemporary musical vocal techniques.

• Analytical Science and Technology
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• v.35 no.3
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• pp.116-123
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• 2022

Polymer bags, metallic canisters, and glass bottles have been used as containers for analyzing the volatile organic compounds (VOCs) in air. In this study, various sampling containers were compared to investigate the short-term stability of VOCs, that is, from the time they are sampled to the time they are analyzed. Polyvinyl fluoride (PVF), polypropylene (PP), polyester aluminum (PE-Al) bags, canisters, and glass bottles were used as sample containers. A 100 nmol/mol standard gas mixture of benzene, toluene, ethylbenzene, m-xylene, styrene, and o-xylene was used for the VOC comparison. Changes in the concentrations of samples stored for 10~20 day in each container were measured using a thermal desorption-gas chromatograph-flame ionization detector (TD-GC-FID). As a result, VOCs stored in a canister and two kinds of amber glass bottles have shown immaterial decreases in concentration in one week, and more than 80 % of the initial concentration was maintained for two weeks. In the case of polymer bags, the concentration of all VOCs, except benzene and toluene, were remarkably decreased below 70% of the initial concentration in one day. Particularly, ethylbenzene, xylene, and styrene have shown dramatic decreases in concentration below 30 % of the initial concentration in all polymer bags in one day.

• Korean small business review
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• v.42 no.2
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• pp.139-177
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• 2020

The concepts of entrepreneurship are very various. So many researchers are confused or not sure of the concepts of entrepreneurship. Likewise, the concept of entrepreneur are very various, and confused of the concepts of entrepreneur. This study try to set a comprehensive conceptual model of concepts of entrepreneurs. This model suggest a prototype model of entrepreneur with historical context and anthropological approach.

• Journal of Popular Narrative
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• v.27 no.2
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• pp.13-44
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• 2021

This article describes the fear of infection through the Covid19 pandemic and the rapid phase change of human species with H. P. Lovecraft's fiction and "Project LC. RC". Pandemic and climate change, which can be called global weirding, fundamentally question the status and history of human species in the ecosystem. The horror creature and cosmological indifferentism in Lovecraft's weird fiction are contemporary in that they help shed light on today's global weirding. But Lovecraft's racism allows him to ask more fundamental questions about the logjam of his cosmic horror. "Project LC. RC" are a Korean writers's works of cultural variation that rewrites controversial racism and misogyny in Lovecraft's fiction. Such variation becomes the task of creating a mutation in Lovecraft as it becomes infected with the affection of Lovecraft's writing. This article first noted the creative power of Lovecraft's fiction that induces such a mutation. And under this premise, this article wanted to reveal the meaning of Lee Seo young, Eun rim, and Kim Bo young's recreates of Lovecraft's fiction through the analysis of images and motifs of abject, plant creature and symbiosis. Specifically, Lovecraft's creature, which evokes phallic fear, turns into an image of an abject embracing and comforting women's despair("I Want You to Stay Low"), a plant creature that provides women with refuge("Color in the Well"), and a creature of care and symbiotic life("A Sea of Plague"). This recreate/rewriting has contemporary significance in that it embodies values such as labor, care, and solidarity in their works. The conclusion noted another power of creative variation in Lovecraft's fiction, which is not reduced to recreate/rewriting.

• Journal of Korean Library and Information Science Society
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• v.53 no.2
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• pp.355-375
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• 2022

This study is to grasp LRM's feature and applications plan to reflect LRM to cataloging related standards and individual system through comparing and analyzing LRM with the FR model in terms of entities, attributes, and relationships. The application plan is suggested as follows. First, the entity can be extended by defining sub-entities of each entity in the standards and the individual system in order to reflect LRM, even though entities such as families, groups, identifiers, authorized access points, concepts, objects, events, agency and rules have been deleted in LRM. Second, the attribute should be subdivided in the standards and the individual system in order to apply LRM, though many attributes have been changed to relationships for linked data and decreased in LRM. In particular, more specific and detailed property names in the standards and the individual system should be clearly presented, and the vocabulary encoding scheme corresponding to each property should be also developed, since properties with similar functions or repetition in various entities, and material specific properties are generalized and integrated into comprehensive property names. Third, the relationship should be extended through newly declaring the refinement or subtype of the relationship and considering a multi-level relationship, since the relationship itself is general and abstract under increasing the number of relationships in comparing to the property. This study will be practically utilized in cataloging related standards and individual system for applying LRM.