• Journal of The Korean Association For Science Education
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• v.29 no.8
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• pp.963-977
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• 2009

The purpose of this paper is to identify college students' conceptions of the earth system cycles as learners of earth science education (ESE) and draw educational implications. An eight-week creative story writing project was held with 62 non-science students taking a general course on earth science. Their creative stories were categorized by analyzing the conceptions and types of cycle with a story mapping technique. The cycle conceptions of earth systems were expressed diversely into 32; most of the cycle types were circular and complex, while the others were branch-shaped and linear types that fail to complete the cycles. College students' conceptions of the earth system cycles is biased toward natural-abiotic systems; less than 30% of them are shown to be aware of all three categories: natural-abiotic, natural-biotic, and human systems. It is essential to diversify the content of education on earth system cycles and help learners develop systematic methods of thinking so that they will be able to recognize the impacts of feedback from human activities through ESE.

• Journal of Internet of Things and Convergence
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• v.10 no.2
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• pp.115-124
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• 2024

This study aimed to examine the mediating effect of self-esteem on the relationship between clinical practice powerlessness and career identity among dental hygiene students with clinical practice experience in the IoT. A questionnaire was conducted on 172 dental hygiene students in a university located in Chungcheong area. For data analysis, Pearson's correlation analysis was conducted to exam the relationships between clinical practice powerlessness, self-esteem, and career identity. Baron & Kenny's three-step mediation analysis was used to investigate the mediating effect of self-esteem in the relationship between clinical practice powerlessness and career identity. The results of this study showed that the clinical practice powerlessness showed significant negative correlations with both self-esteem and career identity, and self-esteem showed a positive correlation with career identity. Partial mediating effects of self-esteem were found between clinical practice powerlessness and career identity. Thus, since self-esteem mediates the relationship between clinical practice powerlessness and career identity, it's essential to implement online-based programs aimed at increasing self-esteem among dental hygiene students before they participate in clinical practice.

• Composites Research
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• v.37 no.1
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• pp.32-39
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• 2024

Solid-state hydrogen storage is gaining prominence as a crucial subject in advancing the hydrogen-based economy and innovating energy storage technology. This storage method shows superior characteristics in terms of safety, storage, and operational efficiency compared to existing methods such as compression and liquefied hydrogen storage. In this study, we aim to evaluate the solid hydrogen storage performance on the nanotube surface by various structural design factors. This is accomplished through molecular dynamics simulations (MD) with the aim of uncovering the underlying ism. The simulation incorporates diverse carbon nanotubes (CNTs) - encompassing various diameters, multi-walled structures (MWNT), single-walled structures (SWNT), and boron-nitrogen nanotubes (BNNT). Analyzing the storage and effective release of hydrogen under different conditions via the radial density function (RDF) revealed that a reduction in radius and the implementation of a double-wall configuration contribute to heightened solid hydrogen storage. While the hydrogen storage capacity of boron-nitrogen nanotubes falls short of that of carbon nanotubes, they notably surpass carbon nanotubes in terms of effective hydrogen storage capacity.

• Composites Research
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• v.37 no.3
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• pp.143-149
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• 2024

This paper measures the mechanical properties of corrugated cardboard, an eco-friendly packaging material, and applies these measurements to the MAT_PAPER model in LS-DYNA for finite element analysis. Although MAT_PAPER is primarily designed for modeling the behavior of paper, this research demonstrates its applicability to corrugated cardboard as well. Tensile, compression, and shear behaviors of a corrugated cardboard were measured and analyzed, and based on these results, six yield surfaces were derived and integrated into the MAT_PAPER model. By comparing the finite element analysis of the material tests and the low velocity collapse analysis of the corrugated cardboard square boxes with each experimental results, it was shown that the behavior of corrugated cardboard could be equivalently considered well by the MAT_PAPER model. However, since the model is not rate-dependent, the high strain rate properties of liner materials were measured and used for strain rate correction. Consequently, this matches well with the results of the high-speed compression tests of the corrugated cardboard square boxes.

• Journal of Digital Convergence
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• v.21 no.3
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• pp.15-22
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• 2023

This study is a case study designed to create and implement a project-based introduction to nursing science, with the aim of analyzing students' experiences and perceptions following its implementation. The study targeted a total of 95 nursing students at G University in S City who enrolled in the introduction to nursing science course in 2021 and 2022. Data collection took place from September 2021 to December 2022, and data analysis involved examining reflective journals submitted by students after completing the project activities, using content analysis. The research results revealed four categories and nine themes. The four categories were 'Making Challenging Studies More Accessible,' 'Engaging and Enjoyable Learning Experiences,' 'Enhanced Teamwork,' and 'Presentation Limitations.' The project-based learning method was found to be effective and applicable in nursing education, demonstrating positive effects on students' attitudes and learning outcomes. However, since the study focused on students from a single university, it is suggested that future research include repeated studies and extend the application to other nursing courses to validate its effects.

• Applied Chemistry for Engineering
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• v.35 no.3
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• pp.260-265
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• 2024

To synthesize an antistatic material for use in semiconductor wafer transport trays, in-situ polymerization of poly(methyl methacrylate) (PMMA) and polyurethane (PU) incorporating carbon nanotubes was designed and conducted. The newly synthesized composites were evaluated for their thermal and electrical conductivity properties under conditions mimicking commercial device manufacturing processes. Comparative analysis of their respective performances revealed that both PMMA and PU containing carbon nanotubes exhibited enhanced thermal properties and superior electrical conductivity as the nanotube content increased. Morphology of the composites synthesized via in-situ polymerization was confirmed to be excellent through FE-SEM analysis, demonstrating good dispersibility. Both PMMA and PU incorporating carbon nanotubes showed outstanding surface resistance values of 10³ Ω/□, indicating their suitability as antistatic materials for semiconductor applications.

• Journal of the Korean institute of surface engineering
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• v.57 no.4
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• pp.265-273
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• 2024

An amperometric sensor for measuring indole-3-acetic acid (IAA) was studied based on a screen-printed carbon electrode (SPCE) coated with a reduced graphene oxide composite electrocatalyst. The PEI-GO dispersion is uniformly formed through a nucleophilic substitution reaction between the active amine group of Polyethyleneimine (PEI) and the epoxide group exposed on the surface of graphene oxide. And The 3-dimensional PEI-rGO AG (Polyethyleneimine-reduced graphene oxide aerogel) complex was easily prepared through simple heat treatment of the combined PEI-GO dispersion. The proposed composite catalyst electrode, PEI-rGO AG/SPCE, showed a two linear relationship in the low and high concentrations in IAA detection, and the linear equation was I_pa = 0.2883C + 0.0883 (R²=0.9230) at low concentration and Ipa = 0.00464C + 0.6623 (R²=0.9894) at high concentration was proposed, and the detection limit was calculated to be 203.5nM±33.2nM. These results showed the applicability of the PEI-rGO AG composite catalyst as an electrode material for electrocatalysts for the detection of IAA.

• Korean Journal of Heritage: History & Science
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• v.49 no.3
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• pp.32-51
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• 2016

This study examines, based on the database of the Institute for the Translation of Korean Classics(ITKC), the garden plants and their symbolism, and the landscape culture recorded in 'Jipkyungjaeyoungsi(the Series of Poems on Gardens Poetry)' in relevance to traditional houses. First, Jipkyungjaeyoungsi had been continuously written since mid-Goryeo dynasty, when it was first brought in, until the late Joseon dynasty. It was mainly enjoyed by the upper class who chose the path of civil servants. 33 pieces of Jaeyoungsi(題詠詩) in 25 books out of a total of 165 books are related to residential gardens. The first person who wrote a poem in relation to this is believed to be Lee GyuBo(1168~1241) in the late Goryeo dynasty. He is believed to be the first person to contribute to the expansion of natural materials and the variation of entertainment in landscape culture with such books as 'Toesikjaepalyoung(退食齋八詠)', 'Gabeunjeungyukyoung(家盆中六詠)'and 'Gapoyukyoung(家圃六詠)'. Second, most of the poems used the names of the guesthouses. Out of the 33 sections, 19(57.5%) used 8 yeong(詠), then it was in the sequence of 4 yeong(詠), 6 yeong, 10 yeong, 14 yeong, 15 yeong, 16 yeong, 36 yeong(詠) and so on. In the poem writing, it appears to break the patterns of Sosangpalkyung(瀟湘八景) type of writings and is differentiated by (1) focusing on the independent title of the scenery, (2) combining the names of the place and landscape, (3) focusing on the name of the landscape. Third, the subtitles were derived from (1) mostly natural landscape focused on nature and garden plants(22 sections, 66.7%), (2) cultural landscape focused on landscape facilities such as guesthouses, ponds and pavilions(3 sections), (3) complex cultural scenery focused on the activities of people in nature(8 sections). Residents enjoy not only their aesthetic preferences and actual view, but the ideation of the scenery. Especially, they display attachment to and preference for vegetables and herbs, which had been neglected. Fourth, the percentage of deciduous tree population(17 species) rated higher(80.9%) compared to the evergreens(4 species). These aspects are similar results with the listed rate in 'Imwonkyungjaeji(林園經濟志)' by Seo YuGu [evergreen 18 species(21.2%) and deciduous trees 67 species(78.8%)] and precedent researches [Byun WooHyuk(1976), Jung DongOh(1977), Lee Sun(2006)]. Fifth, the frequency of the occurrence of garden plants were plum blossoms(14 times), bamboos(14 times), pine trees(11 times), lotus(11 times), chrysanthemum(10 times), willows(5 times), pomegranates(4 times), maple trees(14 times), royal foxglove trees, common crapemyrtle, chestnut trees, peony, plantains, reeds and a cockscombs(2 times). Thus, the frequency were higher with symbolic plants in relations to (1) Confucian norms(pine trees, oriental arbor vitae, plum blossoms, chrysanthemums, bamboos and lotus), (2) living philosophy of sustain-ability(chrysanthemum, willow), (3) the ideology of seclusion and seeking peace of mind(royal foxglove ree, bamboo). Sixth, it was possible to trace plants in the courtyard and outer garden, vegetable and herb garden. Many symbolic plants were introduced in the courtyard, and it became cultural landscape beyond aesthetic taste. In the vegetable and herb garden, vegetables, fruits and medicinal plants are apparently introduced for epigenetic use. The plants that were displayed to be observed and enjoyed were the sweet flag, pomegranate, daphne odora, chrysanthemum, bamboo, lotus and plum blossom. Seventh, it was possible to understand garden culture related to landscaping materials through poetic words such as pavilions, ponds, stream, flower pot, oddly shaped stones, backyard, orchard, herb garden, flower bed, chrysanthemum fence, boating, fishing, passing the glass around, feet bathing, flower blossom, forest of apricot trees, peach blossoms, stroking the pine tree, plum flower blossoming through the snow and frosted chrysanthemum.

• Journal of Dental Rehabilitation and Applied Science
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• v.18 no.3
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• pp.145-155
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• 2002

The results of the present feasibility study are summarized as follows, 1. The three unit bridge of knitted material and UD fibre reinforcement has both the rigidity and the strength against a vertical occlusal load of 75N. 2. Stress concentration at the junctional area between the bridge and the abutments, i.e. between the pontic and the knitted caps was observed. In the case of the bridge with reinforcement straps, it was partly shown that the concentration problem could be improved by simply increasing the fillet size at the area. Further refining in the surface of the junctional area will be needed to ensure a further improvement in the stress distribution. This will require some trade off in the level of the stress and the available space. A parametric study will help to decide the appropriate size of the fillet. 3. Design refinement is a must to improve the stress distribution and realize the most favourable shape in terms of fabrication. The current straight bar with a constant cross section area can be redesigned to a tapered shape. The curve from the dental arch should also be placed on the pontic design. In accordance with design refinement, the resistance of the bridge frame to other load cases should be evaluated. 4. Although not included in the present feasibility study, it is estimated that bridges of the anterior teeth can be made strong enough with the knitted material without further reinforcement using unidirectional materials. In this regard, a feasibility study on design concepts and stress analysis for 3, 4, 5 unit bridge is suggested. 5. Two types of bridge were analysed in terms of fatigue. The safe life design concept, i.e. fatigue design concept, looks reasonable for the bridge where if cracks should form and propagate there is virtually nothing a dentist to do. The bridge must be designed so that no crack will be initiated during the life span. In the case of crowns, however, if constructed with composite resin with knitted materials, it might be possible to repair them, which in general is impossible for crowns of PFM or of metal. Therefore for composite resin crowns, a damage tolerance design concept can be applied and reasonably higher operational stresses can be allowed. In this case, of course, a periodic inspection program should be established in parallel. 6. Parts of future works in terms of structural viewpoint which need to be addressed are summarized as the following: 1) To develop processing technology to accommodate design concepts; 2) More realistic modelling of the bridge and analysis-geometry and loading condition. Thickness variation in the knitted material, taper in the pontic, design for anterior tooth bridge, the effect of combined loads, etc, will need to be included; 3) To develop appropriate design concepts and design goals for the fibre composite FPD aiming at taking the best advantage of knitted materials, including the damage tolerance design concept; 4) To develop testing method and perform test such as static ultimate load test, fatigue test, repair test, etc, as necessary.

• Cartoon and Animation Studies
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• s.28
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• pp.235-263
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• 2012

Regarding the theme park business as an area of cultural content business, this study focuses on the trend of pursuing indoor theme parks as a small-scale small capital strategy escaped from the existing approach oriented to large-scale outdoor complex theme parks. It is because although existing large-scale outdoor complex theme parks require the capital with the scale of hundreds of billion won and also high-level technique and the latest operational know-how that they have a great barrier for new entry as well as enormous risk, the rent indoor theme parks succeed in market entry with efficient risk management and flexible market strategies. Thereupon, this study examines the current status of the children's indoor theme park market with Korean characters as their theme as a new market among the indoor theme parks and also investigates the market strategies of this market in the two aspects of expansion: the expansion of Korean characters' property value and the expansion of the local theme park market. For that, this article reviewed the advanced researches on theme parks and divided the types of theme parks existing in Korea with the criteria of classification by space and theme or classification by main users. Also, among the children's indoor theme parks with Korean characters as their theme, this study visited five ones located in the capital area to examine the current status. And about two located in the capital area and also four in the local area, the current data were received from the persons in charge of the companies for analysis. Also, with the subjects of spectators visiting the 'DIBO VILLAGE, Cheonggye-cheon' newly opened on April 25th, 2012, the research on satisfaction was conducted for analysis. Through that, this study analyzed the structure of the existing children's indoor theme park business with Korean characters as their theme and suggested the ground to analyze the effectiveness of market strategies being implemented. It is expected that this study will establish the clues of systematic and profound discussion for the indoor theme park business that can be said to be the niche market of the theme park business and allow the small-scale areal indoor theme parks to be examined as a significant business model for the local theme park industry. In the aspect of character business as well, it is expected that this will give a chance to establish a new model of spatial storytelling expansion in terms of the property value of Korean animation characters.