• 보존과학회지
• /
• 제38권2호
• /
• pp.124-132
• /
• 2022

본 연구는 국가민속문화재 일월수 다라니 주머니 매듭과 테두리 장식에 사용된 '금속 장식지'를 대상으로 과학적 분석을 통해 재료적 특성을 파악하였다. 금속 장식지는 SEM-EDS 분석을 통해 은(Ag) 및 황(S)이 확인되어 은제 금속박을 배지에 부착하여 제작한 것으로 추정할 수 있다. 황(S)은 농도와 접촉시간에 따라 은(Ag)을 황색부터 흑색까지 변색시킬 수 있다. 현재는 황색을 확인할 수 없으나, 은(Ag)으로 가금사를 만든 사례가 있어 본래 색을 추정하기 위해서는 추가 연구가 필요하다. 배지는 배면까지 적갈색이다. 함께 검출된 알루미늄(Al)과 규소(Si), 철(Fe)은 전통 편금사(片金絲)의 붉은색 접착제로 추정되는 주토(朱土)의 주성분으로, 금속 장식지의 접착제 관련 성분으로 추측된다. GC/MS 분석 결과에서 접착제 성분은 아교(阿膠)로 확인할 수 있었다.

• The Journal of Advanced Prosthodontics
• /
• 제11권6호
• /
• pp.324-330
• /
• 2019

PURPOSE. The aim of the study was to evaluate and compare the fracture resistance and modes of fracture of monolithic zirconia crowns with two preparation designs. MATERIALS AND METHODS. Forty human maxillary first premolar teeth were extracted for orthodontic purposes and divided into two main groups (n=20): Group A: monolithic traditional zirconia; Group B: monolithic translucent zirconia. The groups were further subdivided into two subgroups (n=10): (A1, B1) shoulder margin design; (A2, B2) feather-edge margin design. Teeth were prepared with either a 1 mm shoulder margin design or a feather-edge margin design. The prepared teeth were scanned using a digital intraoral scanner. The crowns were cemented using self-adhesive resin cement. All cemented teeth were stored in water for 7 days and thermocycling was done before testing. All samples were subjected to compressive axial loading until fracture. The fractographic analysis was done to assess the modes of fracture of the tested samples. RESULTS. The highest mean values of fracture resistance were recorded in kilo-newton and were in the order of subgroup A1 (2.903); subgroup A2 (2.3); subgroup B1 (1.854) and subgroup B2 (1.523). One-way ANOVA showed a statistically significant difference among the 4 subgroups. Concerning modes of fracture, the majority of samples in subgroups A1 and B1 were fracture of restoration and/or tooth, while in subgroups A2 and B2, the majority of samples fractured through the central fossa. CONCLUSION. Even though all the tested crowns fractured at a higher level than the maximum occlusal forces, the shoulder margin design was better than the feather-edge margin design and the monolithic traditional zirconia was better than the monolithic translucent zirconia in terms of fracture strength.

• Restorative Dentistry and Endodontics
• /
• 제36권6호
• /
• pp.515-520
• /
• 2011

전치부 치간이개를 치료할 때 가장 어려운 것은 레진으로 축성 후 치아 사이의 "black triangle"없이 치간공극을 메우는 것이다. 이를 위해서는 치경부 형태와 접촉점의 위치에 기초하여 치은 형태를 결정하는 것이 중요하다. 이 증례보고는 적절한 접촉점을 형성하기 위해 비침습적 방법을 사용하여 접촉점의 위치를 설정하였다. 또한 치은-치아 사이에 위치한 Mylar strip을 이용한 기존의 방법을 바꾸어 자연스러운 형태를 갖도록 변형하였다. Mylar strip을 치은연 상방으로 약 1 mm 정도 되게 치은열구에 위치시키고 작은 면구를 치은과 그 사이에 위치시켜 출현윤곽(emergence contour)을 부여하였다. 이와 같은 변형된 방법은 적절한 출현윤곽과 치은형태를 형성하는데 유용하였으며, 임상적용에 유효하였다.

• Structural Monitoring and Maintenance
• /
• 제7권3호
• /
• pp.233-259
• /
• 2020

Using bonded fiber-reinforced polymer laminates for strengthening wooden structural members has been shown to be an effective and economical method. In this research, properties of suitable composite materials (sika wrap), adhesives and two ways of strengthening beams exposed to bending moment are presented. Passive or slack reinforcement is one way of strengthening. The most effective way of such a strengthening was to place reinforcement laminates in the stretched part of the wooden beam (lower part in our case), in order to investigate the effectiveness of externally bonding FRP to their soffits. The model is based on equilibrium and deformations compatibility requirements in and all parts of the strengthened beam, i.e., the wooden beam, the sika wrap composite plate and the adhesive layer. The theoretical predictions are compared with other existing solutions. This research is helpful for the understanding on mechanical behaviour of the interface and design of the composite-wooden hybrid structures. The results showed that the use of the new strengthening system enhances the performance of the wooden beam when compared with the traditional strengthening system.

• 한국식생활문화학회지
• /
• 제31권1호
• /
• pp.105-110
• /
• 2016

The objective of this study was to determine sensory profiles of rice confections. The samples used in this study obtained from Korea (traditional Korea rice snack and local specialty rice snack) and three countries (USA, Japan, and China) were evaluated and compared. The sensory characteristics of five kinds of rice confections were evaluated using a sensory test and were analyzed via quantitative description analysis (QDA), principal component analysis (PCA), and hierarchical cluster analysis (HCA). In the descriptive analysis, 10 trained panelists evaluated sensory characteristics consisting of 19 attributes, and there were significant differences (p<0.05) among the 16 characteristics. For the descriptive data, multivariate analysis of variance was carried out and identified differences among the samples. The PCA of rice confections for the first two principal components could explain 85.66% of the variations. The Korean, Japanese, and Chinese rice confections were savory, gritty, and particle-sized, the other Korean local specialty rice confections were fruity, sweet, honey-flavored, compact, and crispy, and those from the USA were glossy, grainy, bright, adhesive, cohesive, crispy, and sweet.

• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2008년도 추계학술대회 초록집
• /
• pp.153-154
• /
• 2008

High velocity oxy-fuel (HVOF) thermal spraying coating has been used widely throughout the last 60 years mainly in defense, aerospace, and power plants. Recently this coating technique is considered as a promising candidate for the replacement of the traditional electrolytic hard chrome plating (EHC) which pollutes the environment and causes lung cancer by toxic hexa-valent $Cr^{6+}$. In this study, two kinds of cermet coatings, WC-CoCr and WC-CrC-Ni, are formed by HVOF spraying. The wear properties of coatings are evaluated comparatively by reciprocating sliding wear tests at $25^{\circ}C$, $250^{\circ}C$ and $450^{\circ}C$ respectively. Wear rates show that WC-CoCr coatings have better sliding wear resistance than WC-CrC-Ni coatings regardless of temperature due to more, compact and homogeneously distributed WC particles, less metal content, Co, Cr rich metallic bindermatrix with higher fracture strength and better adhesive strength with WC particles.

• 조형예술학연구
• /
• 제3권
• /
• pp.87-144
• /
• 2001

This study looks into historical genealogy of autonomy in art criticism on modernism and presents the view of the judgment and correction about that. A matter of autonomy in art appeared in the attempt to totally reconsider and upset the theory of 'Mimesis' or 'Representation' which was the basis of traditional aesthetic theory. In the traditional theory of representation, they assumed primary image exists first and then tried to obtain visual similarity to it through art works. However, in the theory of autonomy in modernism, they maintained the reduction to pure form' or medium', regarding what art works represents and how similar to primary image are not the true essence of art. In the early 20th century, C. Bell laid the foundation stone of the theory of Formalism', providing that a matter of autonomy is significant form', which is the combination of lines and colors Aesthetic autonomy theory came to a climax by C. Greenberg, who systemized art criticism on modernism in the middle 20th century. According to his theory, the pursuit of the essence of form resulted in the specificity of medium' and flatness. They thought that the autonomy of art would be achieved by eliminating outward social factors from art works. This theory ended by Minimalism preventing the instructive function of art work and only emphasizing its material property. Since the middle 20th century, the autonomy theory was confronted with the limit and intense attack because it resulted in this fixed canon and materialism, so they began laying emphasis on those extrinsic factors around art works such as human life, society, history, and so on. This study focuses on arguing and complementing the limit of autonomy such as the adhesive and fixed canon, and then defining the more dynamic area of it. For this, first, I introduced the view of T. J. Clark and T. Crow who criticized the aesthetic autonomy theory. They denied the transcendental structure of form, and found form only in the association with substantial life and society. And they insisted the dynamism of form by emphasizing form as a result of negation insisted by avant-garde. Second, I researched the view of A. C, Danto and M. Fried, who complemented the traditional autonomy theory. They made autonomy emerge from the fixation of form like flatness through connecting essentialism with historical view. In conclusion, I insist that autonomic position of art make it possible to connect or mediate between material form and human or social elements. Therefore, autonomy should not be reduced to the axis of form or that of society but make interaction between two heterogeneous axes.

• 대한한방종양학회지
• /
• 제4권1호
• /
• pp.177-197
• /
• 1998

This experimental study was carried out to evaluate the effect of Yipahnsan on angiogenic inhibition mechanism. This study investigates the effects of Yipahnsan on angiogenic inhibition mechanism evaluate cell adhesive inhibition effect, DNA fragmantaion analysis, nuclear condensation assay, FACScan analysis, angiogenic lumen formation assay, immunocytochemistry analysis, RT-PCR for mRNA expression, western blot analysis, confocal analysis for $Ca^{2+}influx$. The results were summarized as follows : 1. The cell adhesive inhibition ability was strongly increased from $5{\mu}g/ml$ on ECV304 cell line and ECVPAR cell line. 2. YY water extract caused $G_0/G_1$ arrest peak to existed on the ECV304 cell line. 3. YY water extract caused inhibition of proliferation and inducement of apoptosis on the collagen coated plate in ECV304 cell line. 4. YY water extract inhibited the lumen formation on the matrigel coated plate in ECV304 cell line. 5. YY water extract inhibited the expressions of LFA-1 and ELAM-1 on ECV304 cell line and ECVPAR cell line. 6. YY water extract inhibited the expressions of MMP-9 and uPA on ECV304 cell line and ECVPAR cell line. 7. YY water extract inhibited the expression of integrin ${\alpha}_v{\beta}_3$ on ECV304 cell line and ECVPAR cell line. 8. YY water extract decreased the change of $Ca^{2+}$ in intracellular on ECV304 cell line and ECVPAR cell line. According to the results, Yipahnsan showed to be a key antagonist of integrin ${\alpha}_v{\beta}_3$, and to be induction of apoptosis by p53 through flow cytometry. This report also demonstrated that expressions of MMP-9 and uPA were blocked under the angiogenesis model. Thus, we suggested that Yipahnsan blocks angiogenesis by inducing apoptosis in ECV304 and ECVPAR cell lines, and another oriental herbal medicine that treats qi-stagnation and blood-stasis type also has angiogenic inhibition effects.

• 대한한방종양학회지
• /
• 제4권1호
• /
• pp.17-36
• /
• 1998

This experimental study was carried out to evaluate the effects of Hwallakhyoreungdan on angiogenic inhibition mechanism. In order to investigate the effects of Hwallakhyoreungdan on angiogenic inhibition mechanism, MTT assay, cell adhesive inhibition effect, DNA fragmantaion analysis, Nuclear condensation assay, FACScan analysis, Angiogenic lumen formation assay, Immunocytochemistry analysis, RT-PCR for mRNA expression, Western blot analysis and Confocal analysis for $Ca^{2+}$ change were performed. The results were summarized as follows: 1. The cell adhesive inhibition ability was strong from $5{\mu}g/ml$. 2. The $G_0/G_1$ arrest peak was existed on ECV304 cell-line. 3. The cells on Collagen plate were inhibition of proliferation and inducement of apoptosis by HR water extract. 4. Angiogenic lumen formation was inhibited by HR water extract. 5. LFA-1 and ELAM-1's expression were inhibited by HR water extract. They are commenly participation on inflammation and tumor regeneration. 6. The expression of MMP-9 and uPA were inhibited by HR water extract. 7. The expression of integrin ${\alpha}_v{\beta}_3$ was inhibited by HR water extract. 8. The expression of intracellular molecule were successively inhibited by HR water extract therefore the proliferation of ECV304 cell line was stopped and apoptosis was induced. 9. The change of $Ca^{2+}$ was decreased by HR water extract it cause confusion of signal transduction pathway therefore it was take part in apoptosis. According to the results, Hwallakhyoreungdan showed to be a key antaonist of integrin ${\alpha}_v{\beta}_3$, and to be induction of apoptosis by p53 through flow cytometry. This report also demonstrated that expressions of MMP-9 and uPA was blocked under the angiogenesis model. Thus, we suggests that Hwallakhyoreungdan blocks angiogenesis by inducing apoptosis of ECV304 and ECVPAR cell lines and another oriental herbal medicine that treats blood-stasis type also has angiogenic inhibition effects.

• Composites Research
• /
• 제30권4호
• /
• pp.235-240
• /
• 2017

아교는 수용성을 띄는 접착제로, 이 특징에 의해 물에 약하다는 단점에도 불구하고 전통적인 고가구에 많이 사용되어 왔다. 이러한 단점을 개선하기 위하여 많은 연구가 진행되고 있다. 본 연구에서는 탄소나노튜브를 도입에 따른 아교의 계면특성 및 열적특성 그리고 방수특성 개선에 대한 연구를 진행하였다. 탄소나노튜브의 비율이 증가함에 따라 아교를 이용하여 접착한 돌침대용 목재 샌드위치 판 상부의 실시간 온도측정을 진행하였다. 나무와 아교접착제 간의 계면특성의 변화를 알아보기 위하여 랩 전단 실험을 실시하였고, 습도가 높아짐에 따라 물성이 약해지는 아교의 단점을 개선하기 위하여 탄소나노튜브를 도입에 따른 아교의 방수특성이 개선되는지 대한 실험을 진행하였다. 랩 전단시편을 물에 담근 후 랩 전단 실험을 진행하여 기존의 결과와 비교하여 차이가 얼마나 나는지 비교하였다. 이를 증명하기 위하여 물과의 정적 접촉각을 이용해 탄소나노튜브의 함량에 따른 아교접착제의 소수성 정도를 비교하였다. 실험결과 아교 접착제에 탄소나노튜브를 도입으로 계면특성, 열적특성 및 방수특성이 개선되었다.