• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.1
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• pp.67-72
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• 2022

Concrete prevents corrosion of reinforcing bars due to its strong alkalinity. However, in the sea, strong alkali components with a pH of 12 to 13 are eluted, which adversely affects the ecological environment and growth of marine organisms. In this study, the mechanical properties and durability of the low alkali mortar were evaluated for the development of a low alkali mortar for the 3D printed artificial reefs. As a result of evaluation of strength characteristics, the α-35 mixture, which were produced with fly ash, silica fume and α-hemihydrate gypsum, satisfied the strength requirement 27 MPa in terms of compressive strength. As a result of pH measurement, it was found that mixing with alpha-type hemihydrate gypsum resulted in minimizing pH due to the the formation of calcium sulfate instead of calcium hydroxide production. As a result of the chloride ion penetration resistance test, the α-35 mixture exhibited the best performance, 3844C. As a result of measuring the length change over time, the α-35 mixture showed the shrinkage 33.5% less compared to the Plain mix.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.5
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• pp.20-29
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• 2022

In this study, in order to improve the durability of the cement composite printed with the ME type 3D printer, PDMS, sodium silicate, and a surface hardener were employed. Post-treatment was performed on 3D-printed cement composite by coating after immersion, and the degree of improvement in durability was evaluated. As a result, in all evaluations, the durability performances of the post-processed specimens were improved compared to those of the plain specimens. Water absorption resistance, chloride penetration resistance, and carbonation resistance of the PDMS treated specimens were improved by 36.3 %, 77.1 %, and 50.4 % when compared to plain specimens. Freeze-thaw resistance of the specimens treated with sodium silicate was found to be the most excellent, with an average enhancement of 47.5% compared to plain specimens. It was found that PDMS was the most efficient post-treatment materials for 3D-printed cement composite. However, as suggested in this study, the post-treatment method by coating after immersion may not be applicable to cement composite structures printed with a 3D printer in field. Therefore, a follow-up study needs to be preformed on the durability enhancing materials suitable for 3D printing.

• The Journal of Advanced Prosthodontics
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• v.13 no.3
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• pp.160-171
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• 2021

Purpose. This in-vitro study evaluated and compared the color stability of 3D-printed and conventional heat-polymerized acrylic resins following aging, mechanical brushing, and immersion in staining medium. Materials and methods. Forty disc-shaped specimens (10 mm in diameter and 3 mm thick) were prepared from two 3D-printed [DentaBASE (DB) and Denture 3D+ (D3D)] and one conventional polymethylmethacrylate (PMMA) denture materials. The specimens were thermo-cycled, subjected to mechanical brushing, and were immersed in either coffee, lemon juice, coke, or artificial saliva (AS) to simulate one and two years of oral use. Color measurements of the specimens were recorded by a spectrophotometer at baseline (T0), and after one (T1) and two years (T2) of simulation. The color changes (ΔE) were determined and also quantified according to the National Bureau of Standards (NBS) units. Descriptive statistics, followed by factorial ANOVA and Bonferroni post-hoc test (α=.05), were applied for data analysis. Results. The independent factors, namely material, staining medium, and immersion time, and interaction among these factors significantly influenced ΔE (P<.009). Irrespective of the materials, treatments, and time, the highest and the lowest mean ΔEs were observed for PMMA in lemon juice (4.58 ± 1.30) and DB in AS (0.41 ± 0.18), respectively. Regarding the material type, PMMA demonstrated the highest mean ΔE (2.31 ± 1.37), followed by D3D (1.67 ± 0.66), and DB (0.85 ± 0.52), and the difference in ΔE between the materials were statistically significant (P<.001). All the specimens demonstrated a decreased color changes at T2 compared to T1, and this difference in mean ΔE was statistically significant (P<.001). Conclusion. The color changes of 3D-printed denture resins were low compared to conventional heat polymerized PMMA. All the tested materials, irrespective of the staining medium used, demonstrated a significant decrease in ΔE values over time.

• International Journal of Computer Science & Network Security
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• v.22 no.8
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• pp.15-24
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• 2022

The article clarifies the conditions for information, digital and educational accessibility for higher education seekers with disabilities in terms of distance learning caused by quarantine restrictions. It is established that such conditions are regulated by international and Ukrainian legal documents (The Standard Rules on the Equalization of Opportunities for Persons with Disabilities, Convention on the Rights of Persons with Disabilities, Sustainable Development Goals, Law of Ukraine "On Education", Law of Ukraine "On Higher Education", Strategy for the Development of Higher Education in Ukraine 2021-2031, Development Strategy areas of innovation for the period up to 2030, Development strategy of the sphere of innovation activity for the period up to 2030). As a part of information barrierlessness, Higher Education Institutions (HEI) should provide access to information in various formats and using technologies, in particular Braille script, large-type printing, audio description (audio descriptive commenting), sign language interpretation, subtitling, a format suitable for reading by screen access programs, formats of simple speech, easy-to-read formats, means of alternative communication. The experience of Pavlo Tychyna Uman State Pedagogical University is described. In particular, special attention is paid to the study of sign language: in view of this, the initiative group implemented the project "Learning to hear and overcome social isolation together" with the financial support of the British Council in Ukraine. Within the framework of digital accessibility, the official website of the Faculty of Social and Psychological Education has been adapted for the visually impaired in accordance with WCAG 2.0 World Standards. In 2021, Pavlo Tychyna Uman State Pedagogical University implemented the project "Cultural, Recreational and Tourist Cherkasy Region: Inclusive Social 3D Map" funded by the Ukrainian Cultural Foundation; a site with available content for online travel in the region to provide barrier-free access to the historical and cultural heritage of Cherkasy region was created. Educational accessibility is achieved by increasing the number of people with special educational needs, receiving education in inclusive groups; activities of the Center for Social and Educational Integration and Inclusive Rehabilitation Social Tourism "Bez barieriv" ("Without barriers"); implementation of a research topic for financing the Ministry of Education and Science of Ukraine: "Social and psychological rehabilitation of children and youth with special educational needs by means of inclusive tourism"; implementation of the project "Social inclusion of distance educational process"; development of information campaigns to popularize the ideas of accessibility, the need for its implementation, ongoing training programs and competitions, etc.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.10a
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• pp.156-158
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• 2021

An initial local government center received direct asking from citizens, wrote the documents by hand, and issued them. Later the appearance of computers, printers, and faxes made it possible to handle civil complaints through copying. Since 2010, as the e-government has started, entering civil service requests into computers after identification by themselves and printing the results has become established. In addition, with the introduction of unmanned administrative services, civil services become available in various places, which causes the increased satisfaction of citizens. One of the services is an unmanned civil service issuing machine, and more than 20 kinds of documents, including a copy of resident registration, can be issued directly. Of course, additional help may be needed if citizens are not familiar with the latest technologies. However, the unmanned civil service issuing machine is a highly satisfactory way in that it is less time-limited as citizens can visit a community center or city hall after the end of work. However, the main problem is that resident registration numbers and fingerprint recognition are required depending on the type of issuance, which increases the inconvenience of handling citizen complaints and is shunned. To solve this problem, we aim to study a method for improving the fingerprint recognition method of unmanned civil service issuing machines by expanding personal identification.

• The Journal of the Convergence on Culture Technology
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• v.9 no.3
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• pp.407-413
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• 2023

The purpose of this study is to provide basic information about various methods to easily affix unique embroidery effects to clothes due to the current expansion of digital fashion technology. A comparison of design techniques using virtual and real clothing was used to show the visual expression of embroidery designs. Actual embroidery motifs were created using a computer embroidery machine, DTP embroidery motifs were made by utilizing digitalization techniques, and digital motifs were produced. Then patch pocket type T-shirts were produced using each embroidery technique to compare the visual expression effects on clothing. The results of this comparison are as follows: for real clothing color (3.5), texture (4.0), gloss (3.8), and thickness (3.5). It was found that the color and thickness of the embroidery floss was visually sufficiently show the design texture and gloss. In terms of the embroidery design on virtual garments, the resutls of color (3.8), texture (4.3), gloss (3.9), and thickness (3.6) showed a high degree of similarity to the non-virtual results, confirming that digitized embroidery motifs are also a tool that can fully realize unique embroidery effect.

• Korean Journal of Oriental Medicine
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• v.3 no.1
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• pp.1-15
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• 1997

${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$(1445) is a book compiled the medical achievements of China and Choseon in those times and it's our source of pride to have it In this country. It also deserves careful investigation since this book can provide some clues of features of missing books in China and Korea. The extent of accuracy of xylographica of old books determines the possiblity of in depth further study. So authors attempted to investigate the xylographica of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ one of the 3 main books in Korea. Previous investigation done by Miki Sakae and Kim Doo Jong are noticeable. On the basis of their respective works, we analyzed 'Annals of the Choseon Dynasty' to find records related with ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ and estimated the situation of its publication. We tried figure the situation of those times of China, Japan and Korea(including North Korea) and tried to estimate the book's original xylographica as much as we could. By King Sejong's command, the first draft of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ consisted of 365 books was made by collaboration of civil officials and medical officers during the period from 1443 to 1445. And then from 1451(first year of Moonjong's reign) to 1464(l0th year of Sejo's reign) lots of manpowers were employed and through the process of countless erasure, proofreading, arrangement and rearrangement revised version of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ which is called by Sejo text was completed. After 3 years of wood engraving work, the first printed form of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ (alternately called Seongjong text) in folding case consisted of 266 chapters, 264 volumes came into the world in 1477.(8th year of Seongjong's reign). This was 32 years after the initial completion of the edition. So ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ exists in three forms as Sejong text, Sejo text and Seongjong text respectively. Since those texts were plundered during the Japanese invasion of Korea in 1592, none of the original copy remains within korea. The texts were constantly moved to kadeungcheongieong, to Kongdeungpyeongio, Jesookoan of Edo, to East University of department of classic books, to Cheoncho archives, to the Imperial Museum and finally is kept in the royal palace at present. (Doseoryo text Eulhae printing type) Reduced-size republication books of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ in wooden type were imported at the time of 'Byeongja Korea-Japan Treaty in 1876' and of those 2 books, one copy was treasured in the Royal Household of the Yi Dynasty and than was lost during the Korean War circa 1950. The other remaining copy has been kept succesively by Kojong's imperial grant, Royal doctor Hong Cheol Bo, Hong Taek Joo, Hong Ik Pyo the book agent, and now is kept In Yonsei University Library and this is the only existing copy in Korea at present. In 1965, Dongyang Medical college published the transcription version of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ consisting of 11 books and then in 1981 after edition and arrangement by Choonghoa(中華) publishing company, photoprint copy of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ was published in Keumgang(金剛) publishing company In 1991, October Yeokang(驛江) publishing company producd photocopies of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ which were previously translated into Korean by North Korea Institute of Oriental Medicine and then issued by medical publishing company. In China, two institutes, Zhejiang Institute of Traditional Chinese Medicine and Huzhou Traditional Chinese Medical Hospital cooperated to publish a revised and marked text consiting of 11 books by adding marking points to japanse Edohakhoondang text which were used as a reference. Both the korean and chinese texts issued were grounded by the ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ kept in the royal palace. Any further study concerning ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ can acquire its accuracy and objectivity when the japanese text kept in the royal palace is taken as an original copy.

• Membrane Journal
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• v.11 no.4
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• pp.143-151
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• 2001

We have fabricated mixed-ionic conducting membranes, L $a_{0.6}$S $r_{0.4}$ $Co_{0.2}$F $e_{0.8}$ $O_{3-}$$\delta$/ and L $a_{0.7}$S $r_{0.3}$G $a_{0.6}$F $e_{0.4}$ $O_{3-}$$\delta$/ by the solid state method. Ceramic membranes consisted of perovskite-type structures and exhibited high relative density, >95%. Especially, dense L $a_{0.6}$S $r_{0.4}$Co $O_{3-}$$\delta$/ layer was coated on the L $a_{0.7}$S $r_{0.3}$G $a_{0.6}$F $e_{0.4}$ $O_{3-}$$\delta$/ membranes by using screen printing technique in order to improve oxygen ion flux. We measured oxygen ion flux on uncoated L $a_{0.6}$S $r_{0.4}$ $Co_{0.2}$F $e_{0.8}$ $O_{3-}$$\delta$/, uncoated L $a_{0.7}$S $r_{0.3}$G $a_{0.6}$F $e_{0.4}$ $O_{3-}$$\delta$/, and coated L $a_{0.7}$S $r_{0.3}$G $a_{0.6}$F $e_{0.4}$ $O_{3-}$$\delta$/ membranes. The L $a_{0.6}$S $r_{0.4}$ $Co_{0.2}$F $e_{0.8}$ $O_{3-}$$\delta$/ membranes showed the highest flux, 0.26 mL/min.$\textrm{cm}^2$ at 90$0^{\circ}C$, after steady state had been reached. The oxygen flux of coated L $a_{0.7}$S $r_{0.3}$G $a_{0.6}$F $e_{0.4}$ $O_{3-}$$\delta$/ membranes showed higher value, 0.19 mL/min.$\textrm{cm}^2$ at 95$0^{\circ}C$. This flux was as much as 2 or 3 times higher than those of uncoated L $a_{0.7}$S $r_{0.3}$G $a_{0.6}$F $e_{0.4}$ $O_{3-}$$\delta$/ membranes. 3-$\delta$/ membranes.X> 3-$\delta$/ membranes.membranes.

• Korean Journal of Heritage: History & Science
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• v.55 no.2
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• pp.50-64
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• 2022

This thesis is a study on the woodblock of Donguibogam by Jeolla Gamyeong(Wanyoung Woodblock). It was registered as a tangible cultural property in Jeollabuk-do in 2005. The purpose of this article is to determine the current status and value of the Donguibogam Wanyoung Woodblock. Jeonju Hyanggyo's Wanyoung Woodblock was used to print books in Gamyeong, Jeolla Province. Currently, ten kinds of woodblocks are preserved. In 1987, a wooden bookshelf was installed and preserved in "Jangpangak" of Jeonju Hyanggyo. It is now preserved and managed at Chonbuk National University Museum. Among the ten woodblocks, the Wanyoung woodblock of Donguibogam is presumed to be a woodblock of a book printed by Jeolla Gamyeong in 1814. The value of Donguibogam has long been recognized domestically and internationally. Donguibogam, compiled in 1610, was first published in 1613 in the wood type of Gaeju Gapinja. Following its publication, its value was recognized not only in Joseon but also in China and Japan. In 2009, the first edition of Donguibogam was registered as a UNESCO World Heritage. Accordingly, Donguibogam has been recognized for various aspects, but little research has been conducted on the woodblocks that printed Donguibogam. Therefore, this paper analyzes the current status of the Wanyoung woodblock of Donguibogam, aiming to enhance its meaning and value. King Seonjo presented the ideals of public health care and preventive medicine when compiling Donguibogam, which was distributed according to his instructions. For this reason, the first edition of Donguibogam was registered as a UNESCO World Heritage. It can be said that the production of Donguibogam woodblocks was an important tool in realizing Joseon's ideals through national dissemination. Furthermore, the woodblock of Donguibogam represents the spirit of thinking about the people, going beyond the purpose of printing, and it was meaningful in the spread of medical knowledge among the people. In this article, I will examine the overall contents of the Wanyoung woodblock of Donguibogam to enhance its meaning and value. The results show that the Wanyoung woodblock of Donguibogam is meaningful in that it is almost the only one produced and stored by Gamyeong. Moreover, Wanyoung woodblocks are meaningful in that perfect editions could be preserved and disseminated for a long time, unlike other wood-type prints.

• Korean Journal of Heritage: History & Science
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• v.57 no.1
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• pp.126-144
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• 2024

The chrysanthemum vine pattern box from the Goryeo Dynasty expresses in great detail the representative features of Goryeo Dynasty lacquerware with mother-of-pearl, such as engraving patterns on the surface of fine mother-of-pearl, expressing vine stems using metal wires, and twisting metal wires to form the boundaries of each patterns. While the lacquerware with mother-of-pearl that remains today from the Goryeo Dynasty has the form of a sutra box and a box with lid, the chrysanthemum vine pattern box that is the subject of this study is in the shape of a box with a separate lid and body, making it difficult to estimate the purpose of production or the stored contents. In this study, we attempted to confirm the formative characteristics of the chrysanthemum vine pattern box in order to confirm its original form, and to investigate its structure and production technique through X-ray transmission. In addition, we attempted to identify the use and production purpose of the box by classifying and comparing the previously known lacquerware with mother-ofpearl from the Goryeo Dynasty by type. As a result of the investigation, fabric was confirmed the bottom of body and inner box through X-ray images. Through this, it was confirmed that the 'Mogsimjeopichilgi'(wooden core grabbing fabric technique) of wrapping the object with fabric was used. And through wood grain, it was possible to confirm the wooden board composition of the part presumed to be the restored part and the part presumed to have had existing Jangseog. In addition, it was confirmed that the joints were connected in a Majdaeim(part to part). Based on the survey results, a total of 14 pieces, including 9 Sutra boxes, 3 boxes, and 2 small boxes, that remain from the Goryeo Dynasty were classified by type and examined for similarity. Among them, there is a "Chrysanthemum Vine Pattern Sutra Box" from a private collection in Japan, a "Black Lacquered Chrysanthemum Arabesque Bun Sutra Box" from the Tokugawa Art Museum, a "Sutra Holder" from the British Museum, and a "Small Box with a Mother-of-Pearl Chrysanthemum Vine Pattern" from a private collection in Korea. The pattern composition of five points was most similar to the subject of this study. As a result of comparing the damage pattern, formative characteristics, and structural features of each part, it is presumed that the sutra holder in the British Museum was transformed into its current form from the original the chrysanthemum vine patterned box. Lastly, in order to confirm the purpose of production, that is, the use of this box, we investigated examples of Tripitaka Koreana printed version produced at a time similar to the social atmosphere of Goryeo at the time. Following the Mongol(元) invasion after the Goryeo military regime at the time, sutras appeared to pray for the stability of the nation and the soul of an individual, and with the development of domestic printing and paper in the 13th century, it gradually coincided with the transition from a scroll to a folded form, and the form of a box changed from a box. It is believed that the storage method also changed.