치과용 지르코니아 표면처리방법에 따른 지르코니아와 전장용 도재의 결합강도 관찰

이광영,최성민,Lee, Gwang-Young,Choi, Sung-Min 대한치과기공학회 2019 대한치과기공학회지 Vol.41 No.4

Purpose: The dental CAD / CAM system has been popular with the development of the digital dental industry. Zirconia is a typical material in dental CAD / CAM systems. Zirconia crowns are classified into single layer and double layer. This study is about the double layer crown of zirconia. The surface roughness, bond strength and fracture patterns of the zirconia surface were observed. Methods: Zirconia blocks were cut using a low speed cutter. Sintered to form a plate shape (6mm × 6mm × 3mm). The prepared specimens were surface treated in four ways. Surface roughness and bond strength were measured. And the fracture pattern was observed. Results: Result of surface treatment of zirconia. The surface roughness test results were as ET 2.87 ㎛, ST 2.67 ㎛, LT 2.44 ㎛, AT 2.41 ㎛, CN 2.08 ㎛ order. Bond Strength results were as LT 25.09 MPa, AT 23.27 MPa, ST 21.27 MPa, ET 21.09 MPa, CN 16.12 MPa order. Fracture patterns showed cohesive failure of 25-50% of the bond area. Conclusion: Surface roughness, bond strength and fracture pattern of the zirconia surface were observed. Etching the surface treatment of zirconia materials has been shown to affect the surface roughness. Zirconia special binder treatment has been shown to affect the bond strength improvement.

소결 전 지르코니아 표면처리와 라이너 사용에 따른 지르코니아와 열가압성형도재의 전단결합강도

이광영,조미향,최성민,Lee, Gwang-Young,Cho, Mi-Hyang,Choi, Sung-Min 대한치과기공학회 2015 대한치과기공학회지 Vol.37 No.3

Purpose: This study was intended to investigate the effect of applying liner for chemical bonding and physical surface roughness created on zirconia by using a sandpaper before sintering on the bond strength between the two materials. Methods: Zirconia blocks were cut using a low-speed cutter. Plate-shaped specimen($6mm{\times}6mm{\times}3mm$) was fabricated by sintering after giving surface roughness according to four kinds of sandpapers. Depending on whether or not to use liner, 60 specimens were divided into two groups ZN(non-liner), ZL(liner), and the two groups were subdivided into four groups respectively in accordance with sandpaper used, totaling eight groups (n=10). The surface roughness (Ra) values and shapes before sintering were observed, and shear bond strength after pressing ceramic plasticity was measured with a universal testing machine. For a test of the significance, a one-way ANOVA was performed, and Tukey's multiple comparison test was conducted. Results: The observation of the surface roughness was SB04($2.22{\pm}1.16{\mu}m$), SB08($2.98{\pm}0.33{\mu}m$), SB12($2.44{\pm}1.32{\mu}m$), SB20($2.34{\pm}0.59{\mu}m$) and SA04($2.34{\pm}0.67{\mu}m$), SA08($1.28{\pm}0.90{\mu}m$), SA12($2.03{\pm}1.60{\mu}m$), SA20($2.19{\pm}1.73{\mu}m$). In the case of ZN Group, the shear bond strength was ZN04($23.26{\pm}3.83MPa$), ZN08($21.76{\pm}2.33MPa$), ZN12($20.49{\pm}3.01MPa$), ZN20($24.98{\pm}4.22MPa$)(p<0.05). As for ZL Group, the shear bond strength was ZL04($25.09{\pm}5.67MPa$), ZL08($22.98{\pm}2.26MPa$), ZL12($21.54{\pm}5.70MPa$), ZL20($23.98{\pm}3.23MPa$)(p<0.05). Conclusion: The research results showed that the bond strength of Zirconia core and Pressing ceramic was further improved by physical surface treatment before sintering, rather than by chemical bonding through liner surface treatment.

공동체 문화 활성화를 위한 APT단지 부대복리시설 계획에 관한 연구

이광영,조진만,Lee, Gwang-Young,Cho, Jin-Man 한국주거학회 2008 한국주거학회 논문집 Vol.19 No.2

This study is researched to provide design guidelines of service facilities and programs that apartment residents want along with the increased quality of life. This study is signifiant because it sought effective methods to activate the com-munity culture through service facilities in apartment complexes and the design standard and planning direction for residents. The study results are as follows. In the result of the correlations analysis and multiple regression analysis for the importancy of service facilities in apartment complexes, the following orders were considered as important factor; man-ager office, open space, resident community facility, elderly people meeting and activity facility, walking paths, resident athletic facility, a children's playground, library, and rest areas in the complex. and result of the correlations analysis and multiple regression analysis is the following: service facilities whole importance (y) = 1.413$+0.262^*{\times}1$ (manager office importance)$+0.271^*{\times}2$ (open space importance) $+0.185^*{\times}3$ (resident community facility importance) $+0.136{\times}4$ (elderly people meeting and activity facility importance)$+0.036^*{\times}5$ (walking paths importance) $+0.031^*{\times}6$ (resident athletic facility importance) + $(-0.042)^*{\times}7$ (a children's playground importance) + $(-0.045)^*{\times}8$ (library importance) + $(-0.0097)^*{\times}9$ (rest areas importance).

지르코니아 코어와 전장용 세라믹의 결합 강도에 대한 표면 처리 방법 평가

이광영,홍민호,Lee, Gwang-Young,Hong, Min-Ho 대한치과기공학회 2020 대한치과기공학회지 Vol.42 No.3

Purpose: This study aimed to identify the impact of physical surface roughing with a polishing tool onto the pre-sintering yttria-stabilized tetragonal zirconia polycrystals (TZP) core and liner treatment for chemical bonding on the bond strength of TZP core and veneering ceramic. Methods: Overall, 80 specimens were classified into two groups (non-liner, NL; and usingliner, UL ) depending on the use of liner, and these two groups were then subclassified into four groups depending on the polishing tool used. (1) Non-liner groups: NS, non-liner+stone point; NC, non-liner+carbide bur; NP, non-liner+paper cone point; NT, non-liner+silicon point. (2) Using-liner groups: US, using-liner+stone point; UC, using-liner+carbide bur; UP, usingliner+paper cone point; UT, using-liner+silicon point. The pre-sintering surface roughing values and shapes were observed, and after burning up the veneering ceramic, the shear bond strength was measured using a universal testing machine. For significance testing, a one-way analysis of variance and Tukey's multiple comparison test were conducted. An optical microscope was used to observe the fracture plane, and the following results were obtained. Results: Surface roughness NP (4.09±0.51 ㎛) represented a higher value than other groups (p<0.001). In shear bond strength, NS (35.21±1.44 MPa) of the NL group showed the highest bond strength (p<0.001). The UL group did not show a statistically significant difference between groups (p=0.612). Conclusion: Our study findings reveal that the bond strength of TZP core and veneering ceramic was improved by pre-sintering physical surface treatment than by chemical bonding with liner surface treatment.

친환경학교건축 설계 적용 방향

이광영(Lee, Gwang-Young) 한국교육시설학회 2007 敎育施設 Vol.14 No.1

도시적 관점의 경관계획 및 평가체계에 관한 연구

이광영 ( Gwang Young Lee ),경학봉 ( Hak-bong Kyoung ) 한국공간디자인학회 2019 한국공간디자인학회논문집 Vol.14 No.4

(연구배경 및 목적)최근 도시경관에 대한 관심이 높아지면서 아름다운 도시를 창출하기 위한 각 지방자치단체의 노력이 커지고 있다. 2007년 경관법이 제정된 이후 경관계획에 대해, 또 그것을 평가하기 위한 많은 연구들이 진행되어 왔지만, 10년이상이지난 지금도 건축적 영역과 공공디자인적 영역, 경관적 영역의 구분이 모호하고, 경관계획을 평가하는데 있어 검토하고 있는 요소들은 합리적, 규범적인 접근을 통한 평가항목인지에 대한 의문점을 남기고 있다. 이러한 점은 정부의 경관계획수립지침에 따른 경관체크리스트를 분석하며 확인할 수 있었다. 따라서 본 연구의 목적은 규범적이고 현상학적인 접근을 통해 도시적 경관계획을 시행하고 평가하는데 있어 분석의 틀을 제안하고자 하였다. (연구범위 및 방법)본 연구의 범위는 최근 천안시와 아산시 도시개발 사업에서 경관심의 시 적용된 건축적, 공공디자인적, 도시적 차원의 경관계획 내용을 분석한다. 그리고 내용적 범위는 도시적 경관을 대상으로 하며 그 분석방법은 규범적이고 형상학적인 접근방법과 상관관계분석을 통하여 도시적 차원의 경관계획을 시행하고 평가하는 틀을 제안하고자 한다. (결과) 선행연구의 고찰결과를 통해 인간의 지각, 인지적 특성에 따른 근거에 의하여 건축적 스케일의 접근요소와 공공디자인적 요소들을 제외하고 도시적 차원의 경관계획 접근 요소 16가지를 도출하였고, 그에 대한 세부 내용으로 28가지를 도출하였다. 최종적으로 규범적이고 형상학적인 접근 방법으로 상관성분석을 통해 도출된 체크리스트에서는 기존의 건축적 스케일의 건축항목을 제외하고 도시적 차원의 접근을 통한 경관계획요소가 구성되었다. (결론)이에 본 연구에서는 경관계획을 평가하는데 있어 평가항목을 토지이용, 도시적맥락, 환경ᆞ생태, 도로, 오픈스페이스, 도시실루엣, 스카이라인, 건축물의 규모ᆞ용도, 건축물의 배치ᆞ형상, 공원ᆞ녹지계획, 건축물의 외관, 건축물의 간격, 대지내의 조경, 시설물의 색채, 야간조명 및 기타시설물 등 총 16가지를 도출하였고, 규범적이고 현상학적 접근인 상관성분석을 통해 경관계획 분석의 틀을 만들고 경관계획의 평가방향을 수립하였다. 이를 통해 앞으로 도시경관을 형성하고 평가하는데 있어서 건축적인 접근과 도시경관적 접근을 명확히 구분할 수 있고, 경관평가를 하는데 있어 분석의 틀을 통해 더욱 합리적이고 규범적인 접근의 평가를 할 수 있다. (Background and Purpose)As an interest of urban-landscape has increased recently, the efforts of local governments to create beautiful cities are increasing. Although a lot of studies and evaluations on urban-landscape planning have been done since the enactment of the 2007 national urban-Landscape Act, the diffrence between architectural, public design, and urban-landscape design is still vague even more than 10 years from there and the elements reviewed in evaluating the urban-landscape plan have left the question of whether those are evaluation items through prescriptive approach. This could be confirmed by analyzing the urban-landscape checklists according to the guideline for urban-landscape planning of government. This study is aim to propose the framework of analysis for evaluating the urban-landscape plan through the normative and phenomenological approach. (Method)The scope of this study is in urban landscape planning except for architectural and public design scale, and urban development projects where is developed in Cheonan city and Asan city. the method of this study is done by the method of normative and phenomenological approach and correlation analysis to verify the diffrence and vague between architectural design , public design, and urban-landscape design in urban landscape planning. (Result)Therefore, it was tried to derive the urban-landscape planning elements through the examination of the previous theoretical research and while the architectural scale approach elements and public design elements are excluded by human conceptual-cognitive characteristics which had been clarified by previous theory among the derived elements, it has derived 16 types of approach elements on the urban level, and 28 kinds of detailed contents have been derived. The reconstructed checklist was built as a urban-landscape planning element through the correlation analysis except the existing architectural scale of architectural items. (Conclusion)Thus, this study creates a framework for analysis and the evaluation of the urban-landscape planning by the correlation analysis, and evaluation items are derived into 16 kinds in total in evaluating a urban-landscape plan, such as use of land, urban context, environment and ecology, road, open space, urban silhouette, skyline, size and use of building, layout and shape of building, planning of park and green space, appearance of building, space between buildings, urban-landscape of site, color of facilities, and night lighting and other facilities. Through the result of this study, it is possible to clearly distinguish architectural approach from urban-landscape approach in evaluating urban-landscape planning in the future, and the framework of analysis in urban-landscape planning evaluation can be made by evaluation of the normative and phenomenological approach.

층간분리 효과를 고려한 복합재 핀의 비선형 천음속 플러터 해석

이광영(Gwang Young Lee),김기하(Ki-Ha Kim),김동현(Dong-Hyun Kim) 항공우주시스템공학회 2023 항공우주시스템공학회지 Vol.17 No.6

본 논문에서는 층간분리 현상을 고려한 복합재 미사일 핀의 비선형 천음속 플러터 해석을 수행하였다. 층간분리 효과를 고려한 유한요소 진동해석 기법은 시험 결과와 비교 및 검증하였다. 비선형 천음속 플러터 해석은 자체 개발한 천음속 미소교란 방정식 기반의 시간영역 플러터 해석 프로그램을 개선하여 복합재 날개의 층간분리 효과까지 고려할 수 있도록 확장하여 활용하였다. 복합재 미사일 핀 모델에 대해 층간분리 영역에 따른 아음속, 천음속 및 초음속 플러터 해석을 수행하고 층간분리 영향에 따른 공력탄성학적 특성을 고찰하였다. In this paper, nonlinear transonic flutter analyses of a composite missile fin considering the effect of delamination are conducted. An effective modal analysis methodology is adopted and verified with the experimental modal test data for laminated composite plates with delamination. Extended version of the in-house computational aeroelastic analysis program with the transonic small-disturbance (TSD) code is used in order to predict the flutter dynamic pressure of the delaminated composite fin models. In the subsonic, transonic, and supersonic flow regions, nonlinear time-domain flutter analyses are performed for various delamination conditions, and aeroelastic characteristics due to the delamination phenomena are examined in detail.

Effects of Pre-Sintering Surface Treatment and Liner Application on the Shear Bond Strength of Zirconia and Veneer Ceramic

Gwang-Young Lee(이광영),Min-ho Hong(홍민호) 대한치과재료학회 2014 대한치과재료학회지 Vol.41 No.2

입자형 구조를 갖는 Pd-Ag-In 합금의 시효경화거동

이광영(Gwang-Young Lee),김영오(Young-Oh Kim),조수연(Su-Yoen Cho),설효정(Hyo-Joung Seol),권용훈(Yong-Hoon Kwon),김형일(Hyung-Il Kim) 대한치과재료학회 2012 대한치과재료학회지 Vol.39 No.2

다목적형 치과용 Au-Ag-Pt합금의 시효경화와 관련된 미세구조 및 원소 분포의 변화

이광영(Gwang-Young Lee),권용훈(Yong-Hoon Kwon),김형일(Hyung-Il Kim),설효정(Hyo-Joung Seol) 대한치과재료학회 2012 대한치과재료학회지 Vol.39 No.3