• Journal of Dental Rehabilitation and Applied Science
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• v.36 no.4
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• pp.211-221
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• 2020

The typical biomechanical properties of an internal conical connection (ICC) are axial displacement and loss of preload. The axial displacement of an ICC without a vertical stop can cause the loss of preload and a lowered occlusion. The stress of an ICC is concentrated on the contact interface of the abutment and not on the screw, and during placement, it is important to choose a wider coronal wall thickness as much as possible. The ICC should also be placed below the level of the bone crest. During the restoration of an ICC, care should be taken to ensure an appropriate abutment shape and an accurate connection. To get the best clinical results, it is important to select its wall thickness and place it in the appropriate position to restore it adequately.

• Journal of Dental Rehabilitation and Applied Science
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• v.36 no.4
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• pp.222-231
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• 2020

To use the external connection implant (EXT) appropriately, the inter-implant distance should be carefully considered during placement, and the bones raised above the implants should be trimmed during the second surgery. The hex abutment is more useful than the non-hex abutment. EXT is particularly useful when the inter-arch space is limited. The tissue level (TL, internal butt connection) implant has a biomechanical advantage of coronal wall thickness and a biological advantage of an inherent transmucosal smooth surface. During TL implant restoration, an abutment can be selected using the abutment and fixture margins with considerations for the inter-arch space. Since no single type of implant can satisfy all the cases, it is necessary to select the appropriate type, considering the occlusal force and the bone condition.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.3
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• pp.127-137
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• 2022

Zirconia is fabricated through various processes. Each element in fabricating process can affect the physical properties of the definitive prosthesis. In particular, both the milling process and the sintering process can affect the final integrity of the zirconia prosthesis. Most of the milling machines adopt the ultra-precision 5-axis machining method, and the results vary depending on which milling method was used and how the milling equipment was managed. Milling blocks are selected according to cutting efficiency and aesthetic reproducibility. The sintering method can affect the grain growth and optical properties, and an accurate evaluation can be made only with additional research on the recent speed sintering procedure. Not only the sintering temperature but also the temperature holding time can affect the quality of definitive prosthesis.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.3
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• pp.138-149
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• 2022

The clinical applicability of ceramics can be increased by analyzing the causes of fractures after fracture testing of dental ceramics. Fractography to analyze the cause of fracture of dental ceramics is being widely applied with the development of imaging technologies such as scanning electron microscopy. Setting the experimental conditions is important for accurate interpretation. The fractured specimens should be stored and cleaned to avoid contamination, and metal pretreatment is required for better observation. Depending on the type of fracture, there are dimple rupture, cleavage, and decohesive rupture mainly observed in metals, and fatigue fractures and conchoidal fractures observed in ceramics. In order to reproduce fatigue fracture in the laboratory, which is the main cause of fracture of ceramics, a dynamic loading for observing slow crack growth is essential, and the load conditions and number of loads must be appropriately set. A typical characteristic of a fracture surface of ceramic is a hackle, and the causes of fracture vary depending on the shape of hackle. Fractography is a useful method for in-depth understanding of fractures of dental ceramics, so it is necessary to follow the exact experimental procedure and interpret the results with caution.

• Conservation Science in Museum
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• v.4
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• pp.1-16
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• 2003

For the conservation treatment of the Central Asia mural painting which is to be exhibited in the new museum in Yongsan, we analyzed the pigments used in this mural painting and examined to identify the species of the straw in the wall. We also analyzed the species of the wood of the wooden protective frame and the material of the paper in it, in order to review the material and technique of the conservation treatment performed before the mural painting had been brought to the National Museum of Korea in 1916. The results were as follows: the black pigments of Bon4075 and Bon4078 is carbon(C); the white pigment on the background is gypsum[Ca(SO)₄(H₂O)₂]; the red pigment is lead oxide(Pb₃O₄) and hematite(Fe₂O₃) etc. The straw, which had been mixed into the wall to prevent the wall from cracking, was proved to be either wheat straw or oats straw. The wooden protective frame, which protects the mural painting now, was proved to be made of Salix, Populus, Cryptomeria japonica and pine. The paper discovered in the frame was proved to be made of the bark of a mulberry.

• Journal of Scientific & Technological Knowledge Infrastructure
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• s.14
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• pp.88-91
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• 2004

홍수가 나면 가장 절실한 것이 식수라고 한다. 물이 넘쳐 난린데, 정작 제일 부족한 것 또한 물이라는 얘기다. 지금의 우리 사회도 마찬가지가 아닐까? 정보의 바다라는 인터넷에는 매일 온갖 정보들이 넘쳐나지만, 나에게 꼭 필요한 정보를 적재적소에 찾아내기는 하늘에 별따기다. 오히려 정보가 많으면 많을수록 나에게 적합한 정보를 찾기란 더더욱 힘들어진다. 이런 상황은 과학기술자들도 마찬가지. 정보의 양과 질이 기술개발에 절대적인 영향을 끼치는 요즘, 그들이 전공과 연구과제에 딱 맞는 정보를 정확하게 맞춤으로 전달해주는 것은 첨단 기술개발을 좌우하는 너무나도 중요한 일이고, 참여저어부의 국정지표인 '과학기술 중심 사회'를 열어가는 길이기도 하다. 그리고 바로 그것이, 우리 '정보마케팅'실의 존재 이유다.

• The Science & Technology
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• v.33 no.9 s.376
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• pp.74-75
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• 2000

신경전기생리학이 전공인 조영욱 교수는 통증연구분야에서 주목을 받고 있는 학자중의 한사람이다. 최근 그는 통증억제작용 규명에 진일보된 논문을 발표해 학계의 관심을 모았다. 이 연구를 토대로 발전된 진통기술 및 약제의 개발 가능성을 제공했다는 평가를 받고 있다.

• Conservation Science in Museum
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• v.5
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• pp.5-15
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• 2004

The Fine Art Department has sent a list of ceramic ware to the Conservation Science Laboratory of the National Museum of Korea for conservation treatment. The listed ceramic ware will be newly displayed in the ceramic ware gallery of Yongsan Museum after it is opened. Based on the list, Conservation Science Laboratory has been taking special measures to conservation the ceramic ware since 2002. This paper attempts to introduce the process of restoring the Blue-and-white porcelain Jar with phoenix Design (Jubsoo 631) and Celadon peahen-shaped water dropper (Duksoo 5202).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.4
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• pp.2476-2483
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• 2014

This study aims to review the characteristics of specialized classrooms for governmental secondary schools in the Japanese Colonial Era by analyzing architectural drawings collected by National Archives of Korea. The results of this study are summarized as follows 1) Under the influence of Japanese science promotion of that time, specialized classrooms for science were considered as one of essential facilities. Typically exclusive specialized classrooms were assigned to two major science subjects : physics-chemistry and biology. 2) To science specialized classrooms, ancillary rooms for preparation, experiment equipment and specimen were attached and science lecture room with stepped floor was planned additionally only for the lecture on theories and the demonstration of experiment. 3) Specialized classrooms for science were zoned independently of other facilities because of the special equipments and safety. 4) Art rooms were common to both boys' and girls' schools but concerning music rooms, girls' schools had special concerns, whereas boys' schools did not. 5) Specialized classrooms for homemaking subject of girls' school were as much important as those for science subjects of boys' school. 6) Some early-established Korean boys' schools had handicraft rooms which were the symbol of vocational education-oriented, unequal policy on Koreans. Though not general cases, specialized classrooms for geography-history were planned for Japanese boys' school. Restricted to governmental secondary schools but considering the uncommon state of specialized classrooms of that time, these characteristics show conditions of early time when special classrooms were introduced into Korea.

• The Science & Technology
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• s.508
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• pp.68-69
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• 2011

정경택 교육과학기술부 국제과학비즈니스벨트기획단장은 '해결사'로 불린다. 지난해 교과부 과학기술정책실 정책조정기획관으로 부임해 국가 연구개발 컨트롤타워인 '국가과학기술위원회'를 성공적으로 출범시켰다. 다음 해결 주제는 '말도 많고 탈도 많던' 국제과학비즈니스벨트(과학벨트) 사업이었다. 그는 민간 전문가들로 구성된 '국제과학비즈니스벨트위원회'를 구성해 2년여를 끌어온 과학벨트 입지 선정을 지난 5월 마무리했다. 과학벨트 사업은 여전히 국내외 과학자들의 관심 대상 0순위다. 올 연말 기초과학연구원이 설립되고 내년엔 기초과학연구원 산하 연구단 25개가 선정된다. 과학자들에게 새로운 연구 기회가 생기는 셈이다.