• The Journal of Advanced Prosthodontics
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• v.11 no.5
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• pp.253-261
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• 2019

PURPOSE. To evaluate the influence of cyclic loading on phase transformation of zirconia abutments and to compare the effectiveness of three different quantitative ageing assessment techniques. MATERIALS AND METHODS. Thirty two Y-TZP prostheses fabricated from two brands, InCoris ZI and Ceramill ZI, were cemented to titanium bases and equally divided into two subgroups (n=8): control group without any treatment and aged group with cyclic loading between 20 N and 98 N for 100,000 cycles at 4 Hz in distilled water at $37^{\circ}C$. The tetragonal-to-monoclinic phase transformation was assessed by (i) conventional x-ray diffraction (XRD), (ii) micro x-ray diffraction (${\mu}XRD$), and (iii) micro-Raman spectroscopy. The monoclinic-phase fractions (M%) were compared by two-way ANOVA. RESULTS. InCoris Zi presented significantly higher M% than Ceramill Zi in both control and aged groups (P<.001). Both materials exhibited significant phase transformation with monoclinicphase of 1 to 3% more in aged groups than controls for all three assessment techniques. The comparable M% was quantified by both ${\mu}XRD$ and XRD. The highest M% was assessed with micro-Raman. CONCLUSION. Cyclic loading produced significant phase transformation in tested Y-TZP prostheses. The micro-Raman spectroscopy could be used as an alternative to XRD and ${\mu}XRD$.

• Restorative Dentistry and Endodontics
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• v.46 no.4
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• pp.54.1-54.10
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• 2021

Objectives: The purpose of this study was to quantify phase transformation after hydrofluoric acid (HF) etching at various concentrations on the surface of yttria-stabilized tetragonal zirconia polycrystal (Y-TZP), and to evaluate changes in bonding strength before and after thermal cycling. Materials and Methods: A group whose Y-TZP surface was treated with tribochemical silica abrasion (TS) was used as the control. Y-TZP specimens from each experimental group were etched with 5%, 10%, 20%, and 40% HF solutions at room temperature for 10 minutes. First, to quantify the phase transformation, Y-TZP specimens (n = 5) treated with TS, 5%, 10%, 20% and 40% HF solutions were subjected to X-ray diffraction. Second, to evaluate the change in bond strength before and after thermal cycling, zirconia primer and MDP-containing resin cement were sequentially applied to the Y-TZP specimen. After 5,000 thermal cycles for half of the Y-TZP specimens, shear bond strength was measured for all experimental groups (n = 10). Results: The monoclinic phase content in the 40% HF-treated group was higher than that of the 5%, 10%, and 20% HF-treated groups, but lower than that of TS-treated group (p < 0.05). The 40% HF-treated group showed significantly higher bonding strength than the TS, 5%, and 10% HF-treated groups, even after thermal cycling (p < 0.05). Conclusions: Through this experiment, the group treated with SiO₂ containing air-borne abrasion on the Y-TZP surface showed higher phase transformation and higher reduction in bonding strength after thermal cycling compared to the group treated with high concentration HF.

• Journal of the Korean Mathematical Society
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• v.15 no.2
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• pp.129-137
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• 1979

• Journal of the Korean Mathematical Society
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• v.21 no.1
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• pp.41-48
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• 1984

• Bulletin of the Korean Mathematical Society
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• v.21 no.2
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• pp.139-139
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• 1984

• Journal of the Korean Home Economics Association
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• v.44 no.12
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• pp.167-178
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• 2006

The purpose of this study is to analyze the transformed fashion design based on the principles of visual design. Wucius Wong classified the kinds of transformation techniques as internal variation, external variation, extension, superimposition, transfiguration, dislocation, and distortion, which create and modify the shape. And the kinds of shape grammar for transformation are rule deletion, rule addition, and rule transformation, which are applied to interpretate for the change of wearing, the specialization & development of clothes, and the avant-garde styles in subculture groups. The formative meanings of the transformed fashion design are multi-transformation with complexity, formal beauty pretending confusion, and the basis for new trend.

• Bulletin of the Korean Mathematical Society
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• v.34 no.3
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• pp.469-481
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• 1997

In this paper we define the generalized regular relations with respect to homorphisms and find some properties of those in transformation groups. And we also investigate the equivalent conditions for the generalized regular relations to be transitive.

• Journal of the Chungcheong Mathematical Society
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• v.11 no.1
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• pp.59-71
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• 1998

In this paper we define a regular relation with respect to a homomorphism in transformation groups and we find the equivalent conditions for the relation to be an equivalence relation.

• The Journal of Pediatrics of Korean Medicine
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• v.21 no.1
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• pp.189-209
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• 2007

Objectives : In order to study the effect of Dangkwiyughwangtang and Okbyoungpoongsangamibang on the immune response induced by methotrexate in mice. Method : Delayed type of hypersensitivity, hemagglutinin titer, hemolysin titer, rosette forming cells, phagocytic activity for immune response, lymphocyte transformation, and productivity of Interleukin-2 were measured. Results : Body weight decreasing was significantly inhibited as compared with control group in both the Dangkwiyughwangtang and Okbyoungpoongsangamibang groups. Delayed type of hypersensitivity was significantly increased as compared with control group in both groups Hemagglutinin titer was significantly increased as compared with control group in both groups. Hemolysin titer was significantly increased as compared with control group in the Okbyoungpoongsangamibang group. Rosette forming cells were significantly increased as compared with control group in both groups. Phagocytic activity for immune response was slightly decreased in the Dangkwiyughwangtang group and slightly increased in the Okbyoungpoongsangamibang group insignificantly as compared with the control group. Lymphocyte transformation was significantly increased as compared with the control group in both the Dangkwiyughwangtang and Okbyoungpoongsangamibang groups. Productivity of Interleukin-2 was significantly increased as compared with the control group in both the Dangkwiyughwangtang and Okbyoungpoongsangamibang groups. Conclusion : Both the Dangkwiyughwangtang and Okbyoungpoongsangamibang groups enhance immunity in mice.

• Journal of applied mathematics & informatics
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• v.9 no.2
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• pp.859-867
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• 2002

In this paper, we get a necessary and sufficient condition for an inner automorphism between compact connected semisimple Lie groups to be an atone transformation, and obtain atone transformations of (SU(n),g) with some left invariant metric g.