• Title/Summary/Keyword: 기능성 재료

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Implant restoration considering maintenance for a patient with excessive crown height space (과도한 치관높이 공간을 가진 환자에서 유지관리를 고려한 임플란트 수복증례)

  • Ma, Juri;Yang, Hong-So;Park, Sang-Won;Lim, Hyun-Pil;Yun, Kwi-Dug;Vang, Mong-Sook
    • The Journal of Korean Academy of Prosthodontics
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    • v.51 no.2
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    • pp.107-112
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    • 2013
  • Complications increases when crown height space is excessive and one should be careful of choosing type of fixed prosthesis in case crown height space is over 12 mm. In this condition, tooth seems to be longer, therefore, it is needed to use gingival shade in aesthetically important area for fixed prosthesis. In this case, fixed prosthesis which has inappropriate maintenance and hygiene could hold food, plaque, calculus, thus increase incidence of inflammation and infection. Moreover, it could lead to chronic inflammation and infection and in that case surgical improvement could be necessary. In present case report, gingival inflammation and swelling developed around prosthesis after having made it considering articulation and aesthetic view in patient who had excessive crown height space. Finding out that design of prosthesis is a factor to make it hard to maintain oral hygiene, a temporary prosthesis which has enough interproximal space and proper emergence profile was fabricated. After two months of observation, significant abnormal symptoms are not found and oral reconstruction is performed using fixed prosthesis with zircornia infrastructure and porcelain build-up based on convenient self hygiene design. Through serial treatment, inappropriate soft tissue response is not observed and satisfactory result in functional aspect comes out.

Mechanical strength of Zirconia Abutment in Implant Restoration (지르코니아 임플란트 지대주의 기계적 강도에 관한 연구)

  • Shin, Sung-ae;Kim, Chang-Seop;Cho, Wook;Jeong, Chang-Mo;Jeon, Young-Chan;Yun, Ji-Hoon
    • Journal of Dental Rehabilitation and Applied Science
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    • v.25 no.4
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    • pp.349-360
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    • 2009
  • Purpose: As the esthetic demands of dental implant patients are increased, the demands of zirconia as implant abutment material are also increased. It has non-metalic color, good biocompatibility, high strength and high toughness. Even thought the advatage of zirconia abutment, there are a few studies about mechanical properties of zirconia abutment. This study evaluated the mecanical strength with compressive bending strength and endurance limit of implant-zirconia abutment assembly. Materials and Methods: Static and cyclic loading of implant-Zirconia abutment assembly were simulated under worst case condition according to ISO. Test groups were implants of external butt joint with straight regular diameter and angled regular diameter zirconia abutment, implant of external butt joint with narrow straight diameter zirconia abutment and implant of internal conical joint with straight narrow diameter zirconia abutment. All test group were evaluated the mecanical strength with compressive bending strength and endurance limit. After fatique testing, fracture surface were examined by SEM. Results: The compressive bending strengths exceed 927N. Regular diameter zirconia abutment were stronger than narrow diameter zirconia abutment(P<.05). The endurance limits ranged from 503N to 868N. Conclusion: Within the limitation of this study, zirconia implant abutment exceeded the estabilished values for maximum incisal biting forces reported in the literature.

Comparative Study on the Shape and Symbolism of Flowered-Wall in Tradition Private Houses and Temples - Focusing on the Designated Cultural Properties of Jeollabuk-do Province - (전통민가와 사찰에 나타난 꽃담의 형태와 상징성 연구 - 전라북도 문화재를 중심으로 -)

  • Go, Yu-Ra;Sin, Sang-Sup
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.34 no.3
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    • pp.18-27
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    • 2016
  • A 'flowered-wall,' which are also called a 'flower plant patterned wall,' or a 'flower patterned wall,' is a wall of a building or a fence with various patterns on it. A flowered-wall can be an external mean to look into the owner's authority and values while internally it possesses the symbolic meaning of wishing the well-being and peace of the household. In the research area of the flowered-wall, the walls located in the palace were well researched in various studies across architecture, horticulture, and art design, however, the walls belonging to the local regional traditional folk houses and temples have been involved in little to no research in the landscape architectural area. Taking notice of this perspective this study researched and analyzed the cases of the flowered-walls of the traditional folk houses and the temples that belonged to the national and municipal cultural properties of Jeollabuk-do Province from the landscape architectural perspective. The whole samples were examined and it was shown that there were 9 traditional folk houses with flowered-walls. Among the temples there were 7 cases. Therefore the research focusing on tracing the shape and symbolic meaning of the flowered-walls in the 16 cultural properties located in the Jeollabuk-do Province which consisted of traditional folk houses and temples resulted in the following. Flowered-walls displayed hierarchical differentiation revolving around the main space and its spacial characteristic. This differentiation is variously displayed across the flowered-wall, gable, crack plastering, and chimney. In the case of the folk houses the symbols have the meaning of the prosperity of the household and progeny, exorcism, longevity, number of fortune, harmony, and peace etc that prays for practical wishes such as long life and good health with the prosperity of their descendants. Meanwhile in the temples, symbols indicating an easy passage into eternity, perpetuation of the Buddha-nature, and three marks of existence are applied, differentiating from the folk houses by the appliance of the religious values in the patterns. In conclusion this research resulted in the rightful illumination on the local landscape culture, the possibility of expressing the Korean sentiment through flowered-walls in the contemporary space, the reassessment of flowered-walls, and the provision of basic data for a plan to success the cultural heritage.

A review on the design requirement of temperature in high-level nuclear waste disposal system: based on bentonite buffer (고준위폐기물처분시스템 설계 제한온도 설정에 관한 기술현황 분석: 벤토나이트 완충재를 중심으로)

  • Kim, Jin-Seop;Cho, Won-Jin;Park, Seunghun;Kim, Geon-Young;Baik, Min-Hoon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.21 no.5
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    • pp.587-609
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    • 2019
  • Short-and long-term stabilities of bentonite, favored material as buffer in geological repositories for high-level waste were reviewed in this paper in addition to alternative design concepts of buffer to mitigate the thermal load from decay heat of SF (Spent Fuel) and further increase the disposal efficiency. It is generally reported that the irreversible changes in structure, hydraulic behavior, and swelling capacity are produced due to temperature increase and vapor flow between $150{\sim}250^{\circ}C$. Provided that the maximum temperature of bentonite is less than $150^{\circ}C$, however, the effects of temperature on the material, structural, and mineralogical stability seems to be minor. The maximum temperature in disposal system will constrain and determine the amount of waste to be disposed per unit area and be regarded as an important design parameter influencing the availability of disposal site. Thus, it is necessary to identify the effects of high temperature on the performance of buffer and allow for the thermal constraint greater than $100^{\circ}C$. In addition, the development of high-performance EBS (Engineered Barrier System) such as composite bentonite buffer mixed with graphite or silica and multi-layered buffer (i.e., highly thermal-conductive layer or insulating layer) should be taken into account to enhance the disposal efficiency in parallel with the development of multilayer repository. This will contribute to increase of reliability and securing the acceptance of the people with regard to a high-level waste disposal.

A Study on the Design Guidelines of Healing Landscape in Housing Complexes (공동주택에서 치유조경계획을 위한 가이드라인 연구)

  • Chun, Hyunwoo;Lee, Shiyoung
    • Journal of the Korean Institute of Landscape Architecture
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    • v.44 no.5
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    • pp.26-37
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    • 2016
  • As activities and convenience of residents in outdoor spaces in apartment houses have been considered important, strategies for making outdoor spaces in apartment houses healing spaces have emerged as a major interest. The purpose of this study is to draw elements for planning healing to create healing spaces in collective housing areas and to present design guidelines. The findings of this study are as follows. Functional elements of a healing environment were classified into safe environment, therapeutic environment, ancillary environment, orientation-reinforcing environment, amenities, and social environment. Outdoor spaces in collective housing areas were divided into collective housing entrance areas, internal and external spread areas, outdoor activity areas, and areas by theme. First, collective housing entrance areas should be planned in such a manner that residents can feel the area is private and easy to recognize. Second, internal and external spread areas should be planned in such a manner that they are easy to access and communicate with neighbors. Third, outdoor activity areas should be divided into an open space, resting space, playing space, and sports space. Open spaces should be planned in such a manner that they can command a fine view and respect the privacy of nearby residents. Resting spaces should be equipped with a shelter that protects users from direct sunlight, rain, and snow as well as include a movable bench. Playing spaces should be built considering development of children's curiosity, adventurous spirit, character, stimulation, and physical health. Playing spaces should be designed in such a manner that roadways and sidewalks can be separated for safe traffic. Sport spaces should be planned in such a manner that they can be associated with a pavilion and trail that provide residents with an opportunity to communicate with each other and rest. Fourth, spaces by theme are classified into sense garden, therapeutic garden, experiential garden, and learning garden. Sense gardens are a small garden based on the five senses. Sense gardens should be designed in such a manner that they can improve users' mental and physical health through programs that stimulate the sense of sight, auditory sense, and olfactory sense. Therapeutic gardens should be designed in such a manner that they can provide a comfortable and relaxing space by minimizing noise. It is advisable for therapeutic gardens to be equipped with a medicinal herb garden, meditation garden, and sense garden. Experiential and learning gardens should be designed in such a manner that they can provide users with a space in which they can enjoy nature and leisure activities. It is advisable for experiential and learning gardens to be equipped with a tea garden, vegetable garden, and camping garden. Healing programs should be designed in such a manner that users can feel relaxed by providing a healing environment, making the most of the natural environment. Further research on evaluating whether the findings of this study are effective in healing in a qualitative and quantitative manner is needed.

A Study on the Creation and Use of Nokgakseong and Underwater Wooden Fence (조선시대 녹각성과 수중목책의 조성 및 활용에 관한 연구)

  • SHIM Sunhui;KIM Choongsik
    • Korean Journal of Heritage: History & Science
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    • v.56 no.4
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    • pp.230-246
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    • 2023
  • The wooden fence(木柵), which began to appear in the Bronze Age and is presumed to be the oldest defense facility in human history, was used as a fortress for the purpose of further strengthening military defense functions until after the Japanese Invasion of Korea in 1592 in the Joseon Dynasty(壬辰倭亂). As it was established as the concept of a fortress or a fence installed outside a fence castle(城柵) or barracks fence(營柵), its importance as an essential facility for defense was further highlighted. This study is the result of exploring wooden fence that were used as official facilities during the Joseon Dynasty, focusing on literature surveys such as 『Annals of the Joseon Dynasty』 and 『New Jeungdonggukyeojiseungram』 In this study, in particular, the conclusion of this study is as follows, focusing on the use and function of Nokgakseong(鹿角城), underwater wooden fence, installation methods, and materials of wooden fences, is as follows. The conclusions of this study, which focused on the materials of the wooden fence, are as follows. First, as invasions by foreign enemies became more frequent in the late Goryeo and early Joseon Dynasty, wooden fences played a major role as a major out-of-castle defense facility((防禦施設). In addition, wooden fences were modified and installed into various types such as wooden fences(木柵城), Nokgakseong, a fence made up of large branches in the shape of a deer antler, and underwater wooden fences(水中木柵) according to the circumstances of the times, government policy, and location environment. Second, wooden fences were installed in strategic locations in defense facilities for military purposes, such as mountain fortress(山城), fortresses(營), camps(鎭), forts(堡), and castles(邑城) in strategic locations, and were used for defense in case of emergency. According to the urgency of farming, it was installed in accordance with the non-farming season, when it is easy to mobilize manpower to avoid the busy farming season. The size of the wooden fence of the Joseon Dynasty, which are confirmed through literature records, was converted into Pobaekchuk(布帛尺), and the circumference was very diverse from 4,428chuk(2,066m) to 55chuk(25m). Third, Nokgakseong is an efficient combat support facility that is more aggressive than a general wooden fence, and the records of Nokgakseong in the Annals of the Joseon Dynasty appeared during the King Sejong period the record was 20 times, the most. By region, it was found that it was mainly installed in coastal rugged areas such as Pyeongan and Hamgildo(12), which are the 6-jin areas of the 4th Army. Fourth, in the early 15th century, as the royal court established a maritime defense strategy for the coastal area of the southern coast, after the Sampo Invasion(三浦倭亂), riots by Japanese settlers in Sampo in 1510, major military posts including eupseong(邑城), camps, and forts were established. The installation of underwater barriers around various government facilities rapidly increased as a defense facility to block the warships of Japanese pirates around various government facilities. Fifth, between the 15th and 17th centuries before and after the Japanese Invasion of Korea in Sampo, underwater fences were installed in the Southern coast and Ganghwa Island. In particular, in the 15th century, underwater fences were intensively installed in coastal areas of Gyeongsangnam-do, such as Jepo. Pine trees and Oaks are the main materials used for underwater fences, but other materials such as Oldham's meliosma, Loose-flower hornbeam and The vines of arrowroots were also used as materials for wooden fences.

Quality Grading of Concrete Soil Erosion Control Dam in the Aspect of Unconfined Concrete Strength by Surface-Wave Technique (표면파 기법에 의한 콘크리트 사방댐의 콘크리트 강도 등급 평가)

  • Lee, Chang-Woo;Joh, Sung-Ho;Park, Ki-Hyung;Kim, Min-Sik;Yoon, Ho-Joong;Raja Ahmad, Raja Hassanul
    • Journal of Korean Society of Forest Science
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    • v.101 no.3
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    • pp.412-425
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    • 2012
  • Concrete Soil Erosion Control Dam, which blocks flow of debris flow in torrential stream, are reported to lose expected functions due to structural failure and collapses, caused by poor construction, material deterioration and external impacts. In this paper, an integrity assessment technique for debris barriers was proposed, which allows preliminary detection of problems inherent in debris barriers. The proposed integrity assessment technique is a non-destructive method based on SASW method, one of surface-wave tests. In this paper, a practical procedure and analysis guidelines in applying the SASW technique to debris barrier was proposed and its validity was verified using five decrepit debris barriers older than 20-year old. As a result, the SASW method was validated for the reliable grade evaluation method for concrete soil erosion control dam, and the resulting grades turned out to agree with the results determined by Sabang Associations.

용담댐 건설로 인한 금강 상류의 하천환경변화 분석 II - 수리변화분석 -

  • 정승권;정동양
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.971-976
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    • 2004
  • 하천유지를 위한 하천내 최소유량의 충족은 사실상 환경문제에 제공되는 것으로서 기본적으로 하천변 수생식물의 생태계 서식처를 유지하거나 복원하기 위해 제공된다. 또한 하천유지유량은 하천의 고유종 동${\cdot}$식물을 보전하고, 아름다운 하천에 대한 심미적 질을 유지하며 여가활동 및 상업적 어획고를 최대로 늘릴 수 있거나 과학적 또는 문화적 관심사의 특성을 보호하는 기능을 위한 목적으로도 제공된다. 그러므로 생태학적인 하천유지유량 차원에서 무엇보다 중요한 것은 충분한 물을 확보하고 쾌적한 하천을 유지할 수 있는 맑은 물을 하천에 흐르도록 하는 것이다. 이와 더불어 하천의 생태학적인 측면에서는 서식지 보호를 고려한 계획이 뒷받침되어야 할 것이다. 기존의 개발은 하천정비, 골재채취, 수중 보와 하구 둑 등 하천시설물 건설, 그리고 댐 및 교량건설 등 인위적인 요인에 의하여 하천환경이 심각하게 변화는 경우가 많다. 특히 댐 건설로 인해 하류지역에 수리학적 변화와 하상 변동 등이 발생하고, 이로 인하여 생태계의 변화를 초래하기도 한다. 따라서 본 연구에서는 금강 최상류에 건설된 용담다목적댐에 의해 인위적으로 하천유입량이 감소하고 이로 인해 발생할 수 있는 수리학적 변화를 모의하여 댐 건설이 금강 상류에 미치는 영향을 분석하고자 한다. 이를 위해 2차원 유한요소모형을 이용하였으며, 댐 건설전 자연유출량 및 댐 건설후 하천유지유량에 의한 하천의 건조면적, 습지면적을 산정하였다. 또한 하천의 한계소류력과 하도를 형성하는 재료에 따라 바닥면 전단응력을 산정하여 그 차(差)를 활용하여 유량에 따른 유사이송현황을 모의하였다. 모의된 결과를 visual하게 표현하고자 GIS 기법을 이용하여 주요구간에 대한 유사이송현황을 도시하였다.유역의 고도차를 이용한 흐름특성 분석을 위해 수치고도자료를 이용하여 유역흐름특성을 분석할 수 있는 TOPAZ(Topographic PArameteri-Zation) 프로그램을 이용하였다. TOPAZ 프로그램을 통해 분석된 각 격자별 분포형 수문 매개변수는 적합한 관계식을 통해 분포형 유출량을 모의하는데 적용된다.다 정확한 유입량 예측이 가능할 것으로 사료된다.이 작은 오차를 발생하였으며, 전체적으로 퍼프 모형이 입자모형보다는 훨씬 적은 수의 계산을 통해서도 작은 오차를 나타낼 수 있다는 것을 알 수 있었다. 그러나 Gaussian 분포를 갖는 퍼프모형은 전단흐름에서의 긴 유선형 농도분포를 모의할 수 없었고, 이에 관한 오차는 전단계수가 증가함에 따라 비선형적으로 증가하였다. 향후, 보다 다양한 흐름영역에서 장${\cdot}$단점 분석 및 오차해석을 수행한 후에 각각의 Lagrangian 모형의 장점만을 갖는 모형결합 방법을 제시할 수 있을 것으로 판단된다.mm/$m^{2}$로 감소한 소견을 보였다. 승모판 성형술은 전 승모판엽 탈출증이 있는 두 환아에서 동시에 시행하였다. 수술 후 1년 내 시행한 심초음파에서 모든 환아에서 단지 경등도 이하의 승모판 폐쇄 부전 소견을 보였다. 수술 후 조기 사망은 없었으며, 합병증으로는 유미흉이 한 명에서 있었다. 술 후 10개월째 허혈성 확장성 심근증이 호전되지 않아 Dor 술식을 시행한 후 사망한 예를 제외한 나머지 6명은 특이 증상 없이 정상 생활 중이다 결론: 좌관상동맥 페동맥이상 기시증은 드물기는 하나, 영유아기에 심근경색 및 허혈성 심근증 또는 선천성 승모판 폐쇄 부전등을 초래하는 심각한 선천성 심질환이다. 그러나 진단 즉시 직접 좌관상동맥-대동맥 이식술로 수술

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A Study on Isolation Performance of High Damping Rubber Bearing Through Shaking Table Test and Analysis (진동대 실험 및 해석을 통한 고감쇠 고무받침의 면진성능 연구)

  • Kim, Hu-Seung;Oh, Ju
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.5
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    • pp.601-611
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    • 2016
  • The research, development and use of seismic isolation systems have been increasing with the gradual development of structure safety assurance methods for earthquakes. The High Damping Rubber Bearing (HDRB), one type of seismic isolation system, is a Laminated Rubber Bearing using special High Damping Rubber. However, as its damping function is slightly lower than that of the Lead Rubber Bearing, a similar seismic isolation system, its utilization has not been high. However, the HDRB has a superior damping force to the Natural Rubber Bearing, which has similar materials and shapes, and the existing Lead Rubber Bearing has a maleficence problem in that it contains lead. Thus, studies on HDRBs that do not use lead have increased. In this study, a test targeting the HDRB was done to examine its various dependence properties, such as its compressive stress, frequency and repeated loading. To evaluate the HDRB's seismic performance in response to several earthquake waves, the shaking table test was performed and the results analyzed. The test used the downscaled bridge model and the HDRB was divided into seismic and non-seismic isolation. Consequently, when the HDRB was applied, the damping effect was higher in the non-seismic case. However, its responses on weak foundations, such as in Mexico City, represented increased shapes. Thus, its seismic isolator.

Structural and Functional Roles of Caspase-8 in Extrinsic Apoptosis (Apoptosis의 외인성 경로에서 caspase-8의 구조적 및 기능적 역할)

  • Ha, Min Seon;Jeong, Mi Suk;Jang, Se Bok
    • Journal of Life Science
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    • v.31 no.10
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    • pp.954-959
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    • 2021
  • Apoptosis is an important mechanism that regulates cellular populations to maintain homeostasis, and the caspases, a family of cysteine proteases, are key mediators of the apoptosis pathway. Caspase-8 is an initiator caspase of the extrinsic apoptotic pathway, which is initiated by extracellular stimuli. Caspase-8 have two conserved domains, N-terminal tandem death effector domains (DED) and C-terminal two catalytic domain, which are important for this extrinsic apoptosis pathway. In extrinsic apoptosis pathway, death receptors which members of TNF superfamily are activated by binding of death receptor specific ligands from cell outside. After the activated death receptors recruit adaptor protein Fas-associated death domain protein (FADD), death domains (DD) of death receptor and FADD bind to each other and FADD combined with death receptor recruits procaspase-8, a precursor form of caspase-8. The DED of FADD and procaspase-8 bind to one another and FADD-bound procaspase-8 is activated by cleavage of the prodomain. This death receptor-FADD-caspase-8 complex called death inducing signaling complex (DISC). Cellular FLICE-inhibitory proteins (c-FLIPs) regulate caspase-8 activation by acting both anti- and pro-apoptotically, and caspase-8 activation initiates the activation of executioner caspases such as caspase-3. Finally activated executioner caspases complete the apoptosis by acting critically DNA degradation, nuclear condensation, plasma membrane blebbing, and the proteolysis of certain caspase substrates.