• 구강회복응용과학지
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• 제34권4호
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• pp.306-316
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• 2018

단일 구조 지르코니아는 높은 강도와 파괴 인성을 갖고 있어 고정성 보철 치료에 많이 활용되고 있으나 지르코니아 자체의 불투과성으로 인한 심미적인 한계 때문에 전치부 사용에서 어려움이 있었다. 최근에는 기존 단일 구조 지르코니아보다 투과성이 우수하며, 다양한 착색법을 이용하여 심미성을 개선한 지르코니아 블록들이 개발되고 있다. 3M $Lava^{TM}$ Esthetic 지르코니아는 제조사에 따르면 육방정계 결정상의 비율을 증가시키고 형광성 성분을 추가하여 기존 지르코니아보다 심미성이 우수하다고 소개되고 있다. 본 증례들에서는 심미성을 개선한 단일 구조 지르코니아를 이용하여 전치부를 수복하였으며 기능적, 심미적으로 만족한 결과를 얻었기에 이를 보고하는 바이다.

• The Journal of Advanced Prosthodontics
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• 제16권1호
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• pp.48-56
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• 2024

PURPOSE. To evaluate the metameric disparities among monolithic zirconia materials with differing yttrium compositions across various lighting conditions. MATERIALS AND METHODS. Thirty-six square-shaped zirconia samples measuring 10 × 10 × 0.5 mm were prepared from monolithic zirconia materials with three different yttrium contents. A 0.2 mm thick layer of polymerized dual-polymerizable self-adhesive resin cement was created using a silicone mold with the same dimensions as the prepared zirconia specimens. To evaluate metamerism, color measurements were conducted using a spectrophotometer device on a neutral gray background in a color measurement cabinet that offers four different illumination environments. All samples underwent aging by subjecting them to 10000 thermal cycles using a thermal cycle tester. Following thermal aging, color measurements were taken once more, and the data were recorded using the CIE L^*, a^*, b^* color system. Two-way ANOVA and Post-hoc Bonferroni tests were employed to analyze the data. RESULTS. It was observed that there was no statistical difference among the color measurements made in different illumination environments of the monolithic zirconia ceramics used to evaluate metamerism (P > .05). This observation remained consistent both before and after thermal aging. After thermal aging, the color of monolithic zirconia materials exhibited a tendency towards red and yellow hues, accompanied by a decrease in brightness levels. CONCLUSION. It can be stated that different illumination conditions did not affect the metamerism of monolithic zirconia materials, but there was a color change in monolithic zirconia materials after a thermal aging period equivalent to one year.

• Steel and Composite Structures
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• 제38권1호
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• pp.87-102
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• 2021

To investigate the failure form, bending stiffness, and residual bearing capacity of monolithic composite beams with laminated slab throughout the fire process, fire tests of four monolithic composite beams with laminated slab were performed under constant load and temperature increase. Different factors such as post-pouring layer thickness, lap length of the prefabricated bottom slab, and stud spacing were considered in the fire test. The test results demonstrate that, under the same fire time and external load, the post-pouring layer thickness and stud spacing are important parameters that affect the fire resistance of monolithic composite beams with laminated slab. Similarly, the post-pouring layer thickness and stud spacing are the predominant factors affecting the bending stiffness of monolithic composite beams with laminated slab after fire exposure. The failure forms of monolithic composite beams with laminated slab after the fire are approximately the same as those at room temperature. In both cases, the beams underwent bending failure. However, after exposure to the high-temperature fire, cracks appeared earlier in the monolithic composite beams with laminated slab, and both the residual bearing capacity and bending stiffness were reduced by varying degrees. In this test, the bending bearing capacity and ductility of monolithic composite beams with laminated slab after fire exposure were reduced by 23.3% and 55.4%, respectively, compared with those tested at room temperature. Calculation methods for the residual bearing capacity and bending stiffness of monolithic composite beams with laminated slab in and after the fire are proposed, which demonstrated good accuracy.

• The Korean Journal of Ceramics
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• 제6권2호
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• pp.143-149
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• 2000

Monolithic refractory technology has been developed for RH vessels, with the purpose of reducing the total refractory cost. The technology includes the use of an improved monolithic refractory and microwave drying. The improved monolithic refractory was an alumina-spinel composition, of the type used in steel ladles, to which fine alumina was added to increase the density and corrosion resistance. The microwave drying method, previously developed and used to dry the monolithic lining in steel ladles, was modified for use in drying the dense, 500mm thick lining in RH vessels. This work has resulted in significant cost savings.

• Bulletin of the Korean Chemical Society
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• 제27권1호
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• pp.71-76
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• 2006

Porous polymer monolithic columns were prepared by the direct free radical copolymerization of methacrylic acid and ethylene glycol dimethacrylate within the confines of a chromatographic column in the presence of toluene-dodecanol as a porogenic solvent. The separation characteristics of the monolithic columns were tested by a homologous series of xanthine derivatives, theophylline and caffeine. The effects of the polymerization mixture composition and polymerization condition, mobile phase composition, flow rate and temperature on the retention times and separation efficiencies were investigated. The results showed that the selection of correct porogenic solvents and appropriate polymerization conditions are crucial for the preparation of the monolithic stationary phases. The separation efficiency was only extremely weakly dependent on flow rate and temperatures. Hydrogen-bonding interaction played an important role in the retention and separation. Compared with conventional particle columns, the monolithic column exhibited good stability, ease of regeneration, high separation efficiency and fast analysis.

• Journal of information and communication convergence engineering
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• 제12권3호
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• pp.186-192
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• 2014

Monolithic three-dimensional integrated chips (3D ICs) are an emerging technology that offers an integration density that is some orders of magnitude higher than the conventional through-silicon-via (TSV)-based 3D ICs. This is due to a sequential integration process that enables extremely small monolithic inter-tier vias (MIVs). For a monolithic 3D memory, we first explore the static random-access memory (SRAM) design. Next, for digital logic, we explore several design styles. The first is transistor-level, which is a design style unique to monolithic 3D ICs that are enabled by the ultra-high-density of MIVs. We also explore gate-level and block-level design styles, which are available for TSV-based 3D ICs. For each of these design styles, we present techniques to obtain the graphic database system (GDS) layouts, and perform a signoff-quality performance and power analysis. We also discuss various challenges facing monolithic 3D ICs, such as achieving 50% footprint reduction over two-dimensional (2D) ICs, routing congestion, power delivery network design, and thermal issues. Finally, we present design techniques to overcome these challenges.

• 대한심미치과학회지
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• 제25권1호
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• pp.4-14
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• 2016

CAD/CAM이 치과계에 도입된지도 벌써 꽤 많은 시간이 흘렀음에도 불구하고 현재의 CAD/CAM은 여전히 비효율적이거나 또는 비심미적이다. '효율성' 과 '심미성'이란 두 단어는 지르코이나 보철물에 있어서는 양극에 위치하게 된다. 효율적이기 위해 도재소성없이 monolithic한 지르코니아 보철물을 만들다 보면 비심미적인 경우가 대부분이고, 거꾸로 심미적이기 위해 도재소성 과정을 거치다보면 여전히 사람의 손을 타게되는 비효율성을 피할 수 없기 때문이다. 이 글에서는 지르코니아 보철물의 현주소와 이와 관련된 몇가지 증례들을 보여드리고자 한다.

• 디자인학연구
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• 제19권1호
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• pp.49-58
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• 2006

본 연구는 다원화된 현대건축에서 나타나는 현상의 하나인 단일체적(monolithic) 표현 성향의 특성에 관한 것이다. 다양한 건축적 표현 중에서 단일체 건축은 형태적 산만함이나 분열, 이론에 치중한 형태적 복합성의 난해함을 대치하려는 의도로 해석되고, 현시대의 불안정성, 불확정성, 유동성 등이 강조되는 아방가르드적인 건축이론이나 작품경향에 반해 건축의 위상과 자율성 확립을 통한 반발이기도 하다. 이런 단일체 건축은 단순하고 경제적인 구조를 빈틈없는 외피로 감싼 형태적 엄격함을 보여주면서 인식이 용이한 이미지를 구축함으로써 독자적 아이덴티티를 갖춘 형태의 자립형 건축이라 할 수 있다. 외관의 추상적 형태를 이용해 형태묘사적인 아이덴티티를 구축하거나, 크기나 스케일을 과장함으로써 존재감을 강화시키기도 하며, 색, 재료, 마감, 단면형태 등을 이용하여 내부공간과 외부공간을 중재하는 표피를 전략적으로 탐색하기도 한다. 이런 단일체 건축은 오늘날의 다중적이고 불확정적인 상황에서 건축적 아이덴티터를 확립하기 위한 노력의 일환으로 받아들이는 것이 합당할 것이다.

• Journal of Advanced Marine Engineering and Technology
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• 제33권2호
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• pp.288-294
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• 2009

The purpose of this study is manufacturing of monolithic housing for modularization of steering gear. Monolithic housing is difficult to weld with only rotation and linear motion. It is for this reason that housing of joining parts have a slope of 76.3 degrees. For this reason, welding trajectory was measured by the cooperative controled robot system, and then allowing for measured results, we developed the dedicated system. The developed system can be welded by using only 3 axises in contrast with robot system using 8 axises in housing welding. In addition, we applied CMT and laser welding device to dedicated system and as a result of experiment, sound bead and excellent roundness could be obtained.

• 구강회복응용과학지
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• 제31권4호
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• pp.358-363
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• 2015

이전 단일 구조 지르코니아는 색조의 단조로움 등 심미성의 문제로 전치부 사용에서 어려움이 있었다. 이에 전치부 증례의 지르코니아는 코핑으로만 주로 이용되어 최종보철물은 추가적인 도재 피개가 필요했었다. 이에 따라 도재 파절 등의 문제가 존재하였으나 점차 단일 구조 지르코니아 자체의 투과도와 색조가 개선되어 도재 피개 없이도 사용이 가능해졌다. 본 증례는 63세 남성환자로 단일 구조 지르코니아를 이용하여 전악 보철 수복을 시행해 기능적으로나 심미적으로 만족스러운 결과를 얻었기에 이를 보고하는 바이다.