• Title/Summary/Keyword: Materials data

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Comparison of capsule type resin modified glass ionomer porosity according to mixing methods (혼합방법에 따른 캡슐형 광중합글라스아이노머의 공극률 비교)

  • Kim, Jung-min;Kim, Jin-Woo;Cho, Kyung-Mo;Lee, Yoon;Kim, Eung-Hyun;Park, Se-Hee
    • Journal of Dental Rehabilitation and Applied Science
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    • v.37 no.4
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    • pp.217-224
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    • 2021
  • Purpose: The purpose of this study was to evaluate the porosity of resin modified glass ionomer (RMGI) by different mixing methods. Materials and Methods: Five specimens were prepared for each groups according to capsules and mixing methods. Two RMGI capsule and two mixing machines were used for this study. One resin-modified glass ionomer cement is Fuji II LC (F2LC) and the other is Photac Fil Quick Aplicap (PFQ). For Mixing of RMGI capsule, Rotomix using rotating motion and CM-II using shaking motion were used. After measuring height, radius and mass of specimens, Density was calculated. And porosity was measured using micro-computed tomography (micro-CT). All data were statistically analyzed using T-test, two-way ANOVA to compare between groups at 95% significance level to evaluate the affect of capsule and mixing method on the porosity. Results: The porosity was observed in all specimens generally. And there is significant differece between porosities according to RMGI capsule and Mixing method. The porosity of PFQ was lower than that of F2LC and the porosity of Rotomix was lower than that of CM-II. Conclusion: There was a difference of porosity according to kind of capsules and mixing methods. When using same capsule, less porosity was observed on PFQ than F2LC. When using same mixing mehod, less porosity was observed on Rotomix than CM-II. Using mixing machine of same coporation as that of RMGI capsule did not lead to lower porosity. Therefore, Selecting optimal mixing machine is important.

The development of resources for the application of 2020 Dietary Reference Intakes for Koreans (2020 한국인 영양소 섭취기준 활용 자료 개발)

  • Hwang, Ji-Yun;Kim, Yangha;Lee, Haeng Shin;Park, EunJu;Kim, Jeongseon;Shin, Sangah;Kim, Ki Nam;Bae, Yun Jung;Kim, Kirang;Woo, Taejung;Yoon, Mi Ock;Lee, Myoungsook
    • Journal of Nutrition and Health
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    • v.55 no.1
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    • pp.21-35
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    • 2022
  • The recommended meal composition allows the general people to organize meals using the number of intakes of foods from each of six food groups (grains, meat·fish·eggs·beans, vegetables, fruits, milk·dairy products and oils·sugars) to meet Dietary Reference Intakes for Koreans (KDRIs) without calculating complex nutritional values. Through an integrated analysis of data from the 6th to 7th Korean National Health and Nutrition Examination Surveys (2013-2018), representative foods for each food group were selected, and the amounts of representative foods per person were derived based on energy. Based on the EER by age and gender from the KDRIs, a total of 12 kinds of diets were suggested by differentiating meal compositions by age (aged 1-2, 3-5, 6-11, 12-18, 19-64, 65-74 and ≥ 75 years) and gender. The 2020 Food Balance Wheel included the 6th food group of oils and sugars to raise public awareness and avoid confusion in the practical utilization of the model by industries or individuals in reducing the consistent increasing intakes of oils and sugars. To promote the everyday use of the Food Balance Wheel and recommended meal compositions among the general public, the poster of the Food Balance Wheel was created in five languages (Korean, English, Japanese, Vietnamese and Chinese) along with card news. A survey was conducted to provide a basis for categorizing nutritional problems by life cycles and developing customized web-based messages to the public. Based on survey results two types of card news were produced for the general public and youth. Additionally, the educational program was developed through a series of processes, such as prioritization of educational topics, setting educational goals for each stage, creation of a detailed educational system chart and teaching-learning plans for the development of educational materials and media.

A Relative Study of 3D Digital Record Results on Buried Cultural Properties (매장문화재 자료에 대한 3D 디지털 기록 결과 비교연구)

  • KIM, Soohyun;LEE, Seungyeon;LEE, Jeongwon;AHN, Hyoungki
    • Korean Journal of Heritage: History & Science
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    • v.55 no.1
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    • pp.175-198
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    • 2022
  • With the development of technology, the methods of digitally converting various forms of analog information have become common. As a result, the concept of recording, building, and reproducing data in a virtual space, such as digital heritage and digital reconstruction, has been actively used in the preservation and research of various cultural heritages. However, there are few existing research results that suggest optimal scanners for small and medium-sized relics. In addition, scanner prices are not cheap for researchers to use, so there are not many related studies. The 3D scanner specifications have a great influence on the quality of the 3D model. In particular, since the state of light reflected on the surface of the object varies depending on the type of light source used in the scanner, using a scanner suitable for the characteristics of the object is the way to increase the efficiency of the work. Therefore, this paper conducted a study on nine small and medium-sized buried cultural properties of various materials, including earthenware and porcelain, by period, to examine the differences in quality of the four types of 3D scanners. As a result of the study, optical scanners and small and medium-sized object scanners were the most suitable digital records of the small and medium-sized relics. Optical scanners are excellent in both mesh and texture but have the disadvantage of being very expensive and not portable. The handheld method had the advantage of excellent portability and speed. When considering the results compared to the price, the small and medium-sized object scanner was the best. It was the photo room measurement that was able to obtain the 3D model at the lowest cost. 3D scanning technology can be largely used to produce digital drawings of relics, restore and duplicate cultural properties, and build databases. This study is meaningful in that it contributed to the use of scanners most suitable for buried cultural properties by material and period for the active use of 3D scanning technology in cultural heritage.

Usages and Religious Takes on the Concept of Haewon (해원 개념의 용례와 종교적 전환)

  • Ko, Byoung-chul
    • Journal of the Daesoon Academy of Sciences
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    • v.39
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    • pp.1-32
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    • 2021
  • The purpose of this article is to explain the conceptual changes that the notion of Haewon (解冤) has undergone by examining the evolution of the usages of Haewon. In order to achieve this purpose, I reviewed the conceptual connotations and denotations of Haewon contained in data from the Joseon Dynasty (Section 2), the Japanese colonial period (Section 3), and the scriptures and major preceding research of Daesoon Jinrihoe (Section 4). The research results described in this article are as follows. First, Haewon is a term with historical, social, and cultural characteristics. This means that Haewon, a term that has been used since the Joseon Dynasty, was a concept used to solve collective problems but could also be applied on the individual level. This further means that, if culture is regarded as a collective consciousness or as a collection of material products, Haewon would be a term that contained social and cultural aspirations. Second, Haewon is not a concept that has been impervious to innovation throughout its history. This can be confirmed by the fact that Haewon's scope of application has changed depending on the problem domain (legal, natural disasters, an institutional domain, etc.). Third, Haewon has converted into religious language a doctrinal system that came about after the emergence of Jeungsan. This means that previously the concept of Haewon was mainly used at the legal level in the Joseon Dynasty, but after the emergence of Jeungsan, it became a term in religious language and in doctrine. The materials of Daesoon Jinrihoe show that this concept of Haewon was expanded to be included at the doctrinal level. These research results show a historical shift in the ideological thought contained in the concept of Haewon. As a term in religious language that is included in a doctrinal system, Haewon has an extension of denotations that is applied to the world beyond individuals and societies, yet it maintains connotations of resolving grievances. This concept of Haewon mediates the transformation of the world and creates a rationale by which training and ethical practice are necessary components of that process of transformation.

Step-by-Step Growth Factors for Technology-Based Ventures: A Case Study of Advanced Nano Products Co. Ltd (기술기반 벤처기업의 단계별 성장요인: (주)나노신소재 사례 중심으로)

  • Jeong, Chanwoo;Lee, Wonil
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.16 no.6
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    • pp.85-105
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    • 2021
  • In this study, a case study was conducted on Advanced Nano Products Co.,Ltd, a company that was established in 2000 and has the core technology to produce and commercialize nano materials and ultrafine nano powders based on nano technology. Deviating from the general case study, a case study analysis frame was set based on the theory of technology management and industry-university cooperation theory, and cases were analyzed. In this case study, Advanced Nano Products Co.,Ltd. was analyzed from two analytical perspectives: the establishment of a Management Of Technology system within the company and the Industry-Academic Cooperation activity. Based on this theoretical-based analysis framework, company visit interviews and related data research and analysis were conducted. As a result of the study of the case company, it was possible to derive how the technology management and industry-university cooperation affect the growth stage of the company as follows. First, the strategic use of technology management is an important factor in strengthening the competitive advantage and core competencies of venture companies, and for survival and growth of startups in the early stages. Second, strategic use of technology management and patents and establishment of a patent management system are a part of business strategy and play a pivotal role in corporate performance. Third, the human and material infrastructure of universities affects the growth of companies in the early stage of start-up, and the high utilization of industry-university cooperation promotes the growth of companies. Fourth, continuous industry-academic cooperation activities in the growth and maturity stages of a company's growth stage are the basis for activating external exchanges and building networks. Lastly, technology management and industry-university cooperation were found to be growth factors for each growth stage of a company. In order for a company to develop continuously from the start-up to the growth and maturity stages, it is necessary to establish a technology management system from the beginning and promote strategic technology management activities. In addition, it can be said that it is important to carry out various industry-academic cooperation activities outside the company. As a result of the case analysis, it was found that Advanced Nano Products Co.,Ltd, which performed these two major activities well, overcame the crisis step by step and continued to grow until now. This study shows how the use of technology management and industry-academic cooperation creates value in each growth stage of technology-based venture companies. In addition, its active use will play a big role in the growth of other venture companies. The results of this case study can be a valid reference for growth research of technology start-up venture companies and related field application and utilization.

Verification of the upper limit of results through dilution tests for RIA test (RIA 검사별 희석실험을 통한 결과의 상한치 검증)

  • LEE, Geun Ui;CHOI, Jin Ju;LEE, Young Ji;YOO, Seon Hee;LEE, Sun Ho
    • The Korean Journal of Nuclear Medicine Technology
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    • v.26 no.1
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    • pp.42-46
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    • 2022
  • Purpose In the meantime, there have been not many samples that require dilution, and it has been difficult for the examiner to set an appropriate dilution multiple for RIA test item and report the results. Accordingly, it was judged that it was necessary to set the maximum dilution multiple for each test and to verify the upper limit of the clinical reportable range. Therefore, in this study, the maximum dilution multiple for each RIA test was set and the upper limit of the clinical reportable range was verified accordingly Materials and Methods Among all RIA tests conducted at Asan Medical Center, the study treated on 30 types of tests which also conduct the dilution test. Data from March to July 2021 were collected and analyzed. The study was conducted on samples subjected to serial dilutions such as X2, X4 or X10, X102, X103, X104, X105. Results Among a total of 30 test types, 18 test types have more than 5 N values in the tolerance range of 80~120%. As a result of the verification of maximum dilution multiples, the test set to 104 is 𝛼-fetoprotein and thyroglobulin, and the test set to 103 is CA-125, CEA, and 𝛽-hCG, and the test set to 102 is Free PSA, PSA, CA15-3, SCC, Ferritin, PTH, Cortisol, and Calcitonin. Tests set to 10 include three categories: 𝛽2-Microglobulin, C-peptide, and Testosterone. Conclusion It is expected that it will contribute to improving the quality of nuclear medicine blood tests as the results of dilution experiments can be reported quickly and accurately through the verification of the clinical reportable range.

Occurrence of Uranium-238 and Rn-222 in Groundwater and Its Relationship with Helium Isotope (지하수 내 우라늄-238 및 라돈-222 산출과 헬륨 동위원소와의 상관성 연구)

  • Jeong, Chan Ho;Lee, Yu Jin;Lee, Yong Cheon;Hong, Jin Woo;Kim, Cheon Hwan;Nagao, Keisuke;Kim, Young-Seog;Kang, Tae-Seob
    • The Journal of Engineering Geology
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    • v.31 no.4
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    • pp.659-669
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    • 2021
  • The purpose of this study is to elucidate the relationship between occurrence of natural radioactive materials such as 238U and 222Rn and original mixing ratio of helium isotope of groundwater from various geology, and to suggest the underground aquifer environment from helium original mixing data. 9 groundwater samples were collected from five study areas, and 238U, Rn-222 and helium isotope were analyzed. A high 238U content of the range of 218~477 ㎍ /L in the groundwater occurs in the twomica granite. 4He air-crust mixing ratio and the Rn-222 content show a rough relation, that is, Rn-222 content increases according to the increase of 4He crust mixing ratio. Because of helium and radon are an inert gas, their behavior in underground environment is assumed as an analogous. The 238U content and He isotope in groundwater does not show any distinct correlation. The groundwater can be classified as three groups (air, air-crust mixing, crust-mantle mixing origin) on the diagram of 3He/4He vs 4He/20Ne, which is composed of original mixing line from air-crust-mantle end members. This original mixing of helium can provide the information of underground aquifer characteristic such as the connection with surface environment or isolation condition from air environment.

The Actual State and Transformation of Major Garden Ornaments in Changdeokgung Palace during the Modern and Contemporary Period (근현대기 창덕궁 내 주요 점경물의 실상과 변형)

  • Oh, Jun-Young;Lee, Jae-Yong
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.39 no.1
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    • pp.10-19
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    • 2021
  • This study investigated the actual state and transformation of the major garden ornaments in Changdeokgung Palace(昌德宮) in the modern and contemporary period, focusing on Nakseonjae(樂善齋), Juhamnu(宙合樓), Jondeokjeong(尊德亭), and Daebodanji (大報壇址). This study can be used as useful data for establishing the restoration and maintenance plan of the garden ornaments in Changdeokgung Palace, and the main results of the study can be summarized as follows. First, according to a photo taken by the Czech Vráz, in 1901, a total of six garden ornaments, including a stone pond and odd-shaped stones, were located in the backyard of Nakseonjae. Since liberation, arbitrary relocation of garden ornaments has frequently occurred, and in the process, two odd-shaped stones, originally located on the first floor of the terraced flower bed, have been transferred to the backyard of Gyeonghungak(景薰閣). Second, unlike the late Joseon Dynasty when 「Donggwoldo(東闕圖)」 was produced, odd-shaped stones were arranged symmetrically in the backyard of Juhamnu in the early 1900s. It was a traditional style garden ornament with similar appearance, size, and design. However, all the odd-shaped stones in the backyard of Juhaumnu were relocated to other places in the 1970s and 1980s. One is located at the rear of Aeryeonjeong(愛蓮亭) through the entrance of Bingcheon(氷泉) and the vicinity of Geumcheongyo(錦川橋), and the other remains in front of the Yeongyeongdang Jangnakmun(演慶堂 長樂門). Third, among the garden ornaments located in the area of Jondeokjeong in the past, one odd-shaped stone is now relocated around the stone bridge near the pavilion and the Yeonghwadang(暎花堂) with its components separated. The bondstone near Yeonghwadang was relocated in 1990 for the purpose of installing an imitation of Angbuilgu(仰釜日晷). Another odd-shaped stone has been relocated to the front door of the Secret Garden(後苑), and now it is difficult to grasp the location. Fourth, the two bondstones remaining in the Daebodanji were actually building materials that were used as the foundation stone for the entrance pillars of the Yi Royal Office Building(李王職廳舍) during the Japanese colonial period. After liberation, the Yi Royal Office Building was reorganized into Imperial Estate Administration Office(皇室財産事務總局), and when the office building was burned down in 1960, the stone statues and foundation stones placed on the stylobate were relocated to the Daebodanji. The bondstone at Daebodanji is a representative example of construction materiasl being mistaken for gaeden ornaments.

SSI Education and Scientific Literacy from a Lifelong Learning Perspective (평생학습적 시각을 통해 바라본 SSI 교육과 과학적 소양)

  • Park, Shin-Hee;Kim, Chan-Jong
    • Journal of The Korean Association For Science Education
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    • v.42 no.1
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    • pp.61-75
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    • 2022
  • Recently, lifelong learning ability was newly proposed as scientific literacy, the goal of the science curriculum. To solve various science-related problems students encounter in life, lifelong learning abilities related to science beyond school science education are required, but empirical evidence shows that students can solve problems they actually face through scientific literacy. It is not easy to find in the existing science education research. In addition, there is a lack of discussion on how to cultivate lifelong learning ability suggested in the curriculum through school science education. In this study, attention was paid to SSI education as a method for students to cultivate lifelong learning ability through school science education and to develop their ability to solve science-related problems encountered in life. In this context, statements in the existing SSI education studies were reviewed to discover discourses related to lifelong learning, and their types and characteristics were distinguished. It was possible to confirm lifelong learning and its applicability with focus on science education research through this. For the study, 18 literature materials on the subject of SSI education were selected, and the discourses related to lifelong learning in the SSI education research were discovered by examining the statements revealed in the data. As a result of the study, there are four categories of discourses related to lifelong learning: 'awareness of science,' 'connection between science and everyday life', 'promotion of participatory citizenship', and 'construction of identity'. Various SSI education studies have already had lifelong learning perception in various contexts, and the four types of discourses related to lifelong learning could be linked to the four types of learning presented in the UNESCO Lifelong Learning Report. SSI education tends to view students' life experiences as part of their learning and aims to help students develop the character and capacity to make responsible decisions on social issues related to science and put them into practice. This competency can be continuously connected to the real-life of students outside of school as a lifelong learning ability. This study requires expanding the discourse related to lifelong learning in science education and operating and managing the overall educational system to foster students' lifelong learning ability.

Composition of Curriculums and Textbooks for Speed-Related Units in Elementary School (초등학교에서 속력 관련 단원의 교육과정 및 교과서 내용 구성에 관한 논의)

  • Jhun, Youngseok
    • Journal of Korean Elementary Science Education
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    • v.41 no.4
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    • pp.658-672
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    • 2022
  • The unique teaching and learning difficulties of speed-related units in elementary school science are mainly due to the student's lack of mathematical thinking ability and procedural knowledge on speed measurement, and curriculums and textbooks must be constructed with these in mind. To identify the implications of composing a new science curriculum and relevant textbooks, this study reviewed the structure and contents of the speed-related units of three curriculums from the 2007 revised curriculum to the 2015 revised curriculum and the resulting textbooks and examined their relevance in light of the literature. Results showed that the current content carries the risk of making students calculate only the speed of an object through a mechanical algorithm by memorization rather than grasp the multifaceted relation between traveled distance, duration time, and speed. Findings also highlighted the need to reorganize the curriculum and textbooks to offer students the opportunity to learn the meaning of speed step-by-step by visualizing materials such as double number lines and dealing with simple numbers that are easy to calculate and understand intuitively. In addition, this paper discussed the urgency of improving inquiry performance such as process skills by observing and measuring an actual object's movement, displaying it as a graph, and interpreting it rather than conducting data interpretation through investigation. Lastly, although the current curriculum and textbooks emphasize the connection with daily life in their application aspects, they also deal with dynamics-related content somewhat differently from kinematics, which is the main learning content of the unit. Hence, it is necessary to reorganize the contents focusing on cases related to speed so that students can grasp the concept of speed and use it in their everyday lives. With regard to the new curriculum and textbooks, this study proposes that students be provided the opportunity to systematically and deeply study core topics rather than exclude content that is difficult to learn and challenging to teach so that students realize the value of science and enjoy learning it.