• Journal of the Korean Society of Industry Convergence
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• v.26 no.6_3
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• pp.1297-1303
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• 2023

Research on enhancing the mechanical strength, lightweight properties, electrical conductivity, and thermal conductivity of composite materials by incorporating nano-materials is actively underway. Thermoplastic resins can change their form under heat, making them highly processable and recyclable. In this study, Polyamide-Nylon 6 (PA6), a thermoplastic resin, was utilized, and as reinforcing agents, fused carbon nano-materials (FCN) formed by structurally combining Carbon Nanotube(CNT) and Graphene were employed. Nano-materials often face challenges related to cohesion and dispersion. To address this issue, Silane functional groups were introduced to enhance the dispersion of FCN in PA6. The manufacturing conditions for the composite materials involved determining the use of a dispersant and varying FCN content at 0.05 wt%, 0.1 wt%, and 0.2 wt%. Tensile strength measurements were conducted, and FE-SEM analysis was performed on fracture surfaces. As a result of the tensile strength test, it was confirmed that compared to pure PA6, the strength of the polymer composite with a content of 0.05 wt% was improved by about 60%, for 0.1 wt%, about 65%, and for 0.2 wt%, the strength was improved by 50%. Also, when compared according to the content of FCN, the best strength value was shown when 0.1 wt% was added. The elastic modulus also showed an improvement of about 15% in the case of surface treatment compared to the case without surface treatment, and an improvement of about 70% compared to pure PA6. Through FE-SEM, it was confirmed that the matrix material and silane-modified nanomaterial improved the dispersibility and bonding strength of the interface, helping to support the load evenly and enabling effective stress transfer.

• The Mathematical Education
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• v.62 no.4
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• pp.457-471
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• 2023

Measurement is an imperative content area of early elementary mathematics, but it is reported that students' understanding of units in measurement situations is insufficient despite its importance. Therefore, this study examined lower-grade elementary students' quantitative reasoning of units in length measurement by identifying the levels of reasoning of units. For this purpose, we collected and analyzed the responses of second-grade elementary school students who engaged in a set of length measurement tasks using an open number line in terms of unitizing, iterating, and partitioning. As a result of the study, we categorized students' quantitative reasoning of unit levels into four levels: Iterating unit one, Iterating a given unit, Relating units, and Transforming units. The most prevalent level was Relating units, which is the level of recognizing relationships between units to measure length. Each level was illustrated with distinct features and examples of unit reasoning. Based on the results of this study, a personalized plan to the level of unit reasoning of students is required, and the need for additional guidance or the use of customized interventions for students with incomplete unit reasoning skills is necessary.

• The Mathematical Education
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• v.63 no.2
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• pp.369-385
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• 2024

With the advancement of digital technology, a variety of digital materials are being utilized in education. For their appropriate use of digital resources, teachers need to be able to evaluate the quality of digital resource and determine the suitability for teaching. This study explored how preservice teachers evaluate TocToc-Math, an Artificial Intelligence (AI)-based math support system. Based on an evaluation framework developed through prior research, preservice teachers evaluated TocToc-Math with evidence-based criteria, including content quality, pedagogy, technology use, and mathematics curriculum alignment. The findings shows that preservice teachers positively evaluated TocToc-Math overall. The evaluation tendencies of preservice teachers were classified into three groups, and the specific characteristics of each factor differed depending on the group. Based on the research results, we suggest implications for improving preservice teachers' evaluation abilities regarding the use of digital technology and AI in mathematics education.

• Journal of the Korean Society of Industry Convergence
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• v.27 no.1
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• pp.207-212
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• 2024

Recently, with the strengthening of environmental regulations, there has been an increasing interest in eco-friendly energy sources, leading to a trend of the increasing scale of Cargo Containment Systems (CCS) for Liquefied Natural Gas (LNG) carriers. Among these systems, membrane tanks have gained popularity in LNG transport vessels due to their superior spatial utilization and competitiveness. However, due to high initial investment costs and the difficulty in repair in case of damage, a safety layer, the secondary barrier, must be installed without fail. In this study, in order to apply a new secondary barrier to the existing membrane-type LNG CCS, tests were conducted on the fiberglass layer previously used in the Triplex-Flexible Secondary Barrier (FSB), substituting it with basalt fiber. Tensile and vertical tensile tests were performed to assess the newly applied material. Environmental tests were conducted at room temperature (25℃) and extremely low temperatures (-170℃), considering the temperatures to which substances may be exposed during LNG vessel operations. The basalt-FSB produced in this study demonstrated superior results compared to the specifications of the existing product, confirming its potential applicability for implementation.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.2
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• pp.40-53
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• 2019

This study was conducted to investigate the changes in Scenic Spots by utilizing the "Sinjeungdonggukyeojiseungram(新增東國輿地勝覽)" and "Joseonhwanyeoseungnam(朝鮮?與勝覽)" to interpret "Joseonmyeongseungsiseon(朝鮮名勝詩選, 1915)". By examining the historical context when "Joseonmyeongseungsiseon" was published, it documented the Japanese's memories of 'Sino-Japanese War(淸日戰爭)' in 1894, which implies the 'policy of assimilation' by the Japanese Government-General of Korea after the Japanese annexation of Korea(1910). Detailed information about the author 'Narushima Sagimura(成島鷺村)' can be found in preface. In the "Joseonmyeongseungsiseon", it dedicates most of the part in describing the Scenic Spot especially in 'Anseong Do (15 lines)', where has the memories of war such as the 'First Sino-Japanese War'. The number of Scenic Spots, commonly mentioned in both "Sinjeungdonggukyeoji seungram" and "Joseonhwanyeoseungnam" in Cheonan province are 13 in total. Most of the content contains a similar structure. But 'Honggyeongwon(弘慶院)' and 'Seonghwanyeok(成歡驛)' has both the common Joseon Dynasty landscape point of view, and the additional historical context which are about the 'Jeongyujaeran(丁酉再亂)' or 'First Sino-Japanese War' consequently enlightens the 'placeness' of the Scenic Spots. Among the newly described Scenic Spots, 'Anseongdo(安城渡)' is the part that focuses on the memory of the 'Anseongcheon Battle' that gave Japan its first defeat in the Sino-Japanese War. Especially, by introducing the poetry of 'Sinobu Shunpei' it maximizes the appreciation through emphasizing the direct correlation between placeness and the poem itself. While the Joseon Dynasty poems are 10 pieces in total and their title and the subject matters are all related to historical spots, and the appreciation also maximizes when fully interpreted with understanding the historical context. However, it's contextual meanings are neglected by dividing the actual structures into separate pages. When looking at the location of famous historic sites, they come in many different types, considering the location, meaning, size, and conditions surrounding them. It appears as a service space for travelers, a place for sightseeing, relaxation or return, a temple space for paying respects or memorial services, a fortress facility for defense and protection, or a fishing area for wages, and an old battlefield. Especially, it is noted that the area is diverse as the cultural landscape of Cheonan, given that the battle space between the hermitage and the Donghangnongmin(東學農民) is shared with each other. It is necessary to establish policies for the preservation and restoration of local cultural assets based on these points in the future.

• Journal of the Korean Vacuum Society
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• v.16 no.2
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• pp.116-121
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• 2007

TiNi shape memory alloy(SMA) was fabricated by PLD(plused laser deposition) using equiatomic TiNi target. Composition and crystallization of TiNi thin films which were fabricated in ambient Ar gas(200m Torr)and vacuum($5{\times}10^{-6}\;Torr$) were investigated. Composition of TiNi thin films was characterized by energy-dispersive X-ray spectrometry (EDXS) and crystallization was confirmed by X-ray diffraction (XRD). The composition of films depends on the distance between target and substrate but does not sensitively depend on the substrate temperature. It is found that the composition of films can be easily controlled when substrate is placed inside plume in ambient Ar gas. It is also found that the in situ crystallization temperature ($ca.\;400^{\circ}C$) in ambient Ar gas is lowered in comparison with that of TiNi film prepared under vacuum. The low crystallization temperature in ambient Ar gas makes it possible to prepare the crystalline TiNi thin film without contamination.

• Journal of the Korean Electrochemical Society
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• v.15 no.1
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• pp.48-53
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• 2012

Polyethylene (PE) separator is the most popular separator for lithium-ion batteries. However, it suffers from thermal contraction and mechanical rupture. In order to improve the thermal/mechanical dimensional stabilities, this study investigated the effects of $Si_3N_4$ coating. SCS (Silicon-nitride Coated Separator) has been fabricated by applying 10 ${\mu}m$-thick $Si_3N_4$/PVdF coating on one side of PE separator. SCS exhibits enhanced thermal stability over $100{\sim}150^{\circ}C$: its thermal shrinkage is reduced by 10~20% compared with pristine PE separator. In addition, SCS shows higher tensile strength than PE separator. Employing SCS hardly affects the C-rate performance of $LiCoO_2$/Li coin-cell, even though its ionic conductivity is somewhat lower than that of PE separator.

• Journal of the Korea Fashion and Costume Design Association
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• v.21 no.4
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• pp.43-54
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• 2019

This study analyzed the casula wearing by Catholic priests. By understanding various applications of the priests' wearing of casula, we can understand the meaning of wearing casula, situational judgment, and the role and status of priests. Ultimately, the Catholic symbol and meaning of the casula can be found. The purpose of this study is to examine the basic setting of the casula, the setting according to the status of the priest, and the origin of the casula. Second, this study to understand the design of the pattern shown in the casula. The patterns containing the symbol and the liturgical period were examined, and the method of making the pattern design was considered. Third, various symbols appearing in examples of priests' rituals were considered and analyzed. The method of this study was to utilize various pictures acquired during interviews with priests and nuns and to perform content verification. As a result of this study, the aspects of form, color, and pattern were shown through the wearing of casula during various situations. First, the morphological symbols appearing in the rituals are the simplified casula that hangs on the stola on the top of the alb and the symbols of the form according to the priest's status. In the liturgy, the casula is put on the outermost side as for basic wearing, but in the case of celebration or the attendance at celebrations other than the liturgy, it is the same as simplified wearing. Second, in terms of the symbol and color, the basic colored casulas were worn to match the time and character of the liturgy, and in addition, on the priests' ordination ceremony and celebration day the priests wore white casulas. Third, the symbol of the pattern used in the casula was a Cathoric pattern according to the period in the basic casula wearing of the liturgy. In addition, the patterns were produced by combining the patterns and meaning of the priests that were used in the casulas of the priests' ordination ceremony. The design of the pattern used in the beatification mass casula and the Mass of Peace casula during the Pope's visit to Korea in 2014 used the same motif as the Pope's design, but the simplified pattern was produced for the casula of the Cardinal and bishops. Through this, it is possible to understand the situation where a morphological symbol appears due to a distinction according to the role and status of the priest. This shows that the symbols that appear are the cross and should also consider the complexly, shape, color, and pattern.

• Journal of Science of Art and Design
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• v.13 no.1
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• pp.61-86
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• 2008

Buddhism and Buddhist art originated in India, but when they were introduced to different countries, they created an international environment. Buddhism was introduced as cultural package, with written texts, visual images, rituals, and the organization of monasteries. Buddhist art originated in India during the reign of King Asoka and then was developed under the political, intellectual, artistic, religious, social and natural environments of the regions. The stupa and the chaitya halls create monastic environment. The natural environment of the trade routes and caravans in the Central Asian deserts preserved brilliant-colored murals and helped spread tram India to China. When Buddhism and Buddhist art were introduced to China, Korea, and Japan, Buddhism became a part of government institution and social organization. Gigantic statues were carved in caves in mountains for political purposes. The Chinese transformed the stupa into a square pillar and created pagodas with tiled roofs in tower forms. Koreans not only transmitted the Buddhist art from China to Japan, but it also changed it with originality in the iconography of the pensive bodhisattva images and in the architecture of Seoggulam. The official ideology of Neo Confucian philosophy brought the rise of Chan Buddhism. Zen monasteries in Japan created unique environments by establishing the Zen Buddhist garden. to prompt believers to meditate. An important development in Buddhist art is the Esoteric Buddhist art in China and Tibet. This category belongs to the intellectual, religious as well as artistic environments. The Tibetan deities with consorts in their embrace symbolize the union of the god and the devotees. Buddhist art created a unique environment that was spread out to many nations and changed greatly over time.

• Current Research on Agriculture and Life Sciences
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• v.20
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• pp.9-18
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• 2002

A total of 31 C. chinense lines selected from 2000 screening were tested again for resistance to P. capsid but resistance was not found in tile lines. A total of 26 selections from Korean land races tested 2001 spring were tested again for resistance to P. capsici, KC180, KC230, KC195 and KC194 showed moderate resistance to P. capsid. However, it was apparent on the basis of horticultural characteristics that KC180 and KC230 had been naturally crossed with AC2258 and CM334, respectively. CM334 and AC2248 seed lots that were increased in different years were taken out and tested for resistance to improve their genetic purity because the resistant genetic resources have been showing some off-types in tile population. Off-types began to be found in 1992 seed lots and tile proportion and degree of tile offs was increasing with time up to 2001. Plants true to the type in 1992 seed lots were selected and their inbred seeds were mass produced in a net cage in the greenhouse. AC2258 included in the experiment together was uniform. In 1995 seed lots of CM334, plants with resistance to P. capsici and low or no number of lateral branching at cotyledonary axil, although they were off from tile original CM334, were found and selection was applied to breed lines fixed in tile characters.