• 대한치과의료관리학회지
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• 제11권1호
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• pp.38-46
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• 2023

Composite resins, commonly used in clinical practice, have been developed to improve aesthetics to obtain smooth surfaces. Although the restored composite resin has a smooth surface, it gradually becomes rough over time. Therefore, this study measured glossiness to evaluate the surface of various composite resins and attempted to evaluate the maintenance of glossiness of composite resins by observing surfaces that change to roughness. Specimens were produced using resin used in clinical practice: Gradia direct anterior (GA), Tetric N-Ceram (TN), Ceram.X Sphere TEC one (CX), Filtek Z350XT (FT), Estelite sigma quick (ES). After creating a smooth surface with slide glass, five locations were randomly selected to measure surface gloss, and the average was the representative value of the specimen. Roughness was applied to the specimen under water pouring at the same speed and pressure using SiC paper #2400, 1200, and 400. The gloss unit of different SiC papers was measured. To evaluate the gloss unit and gloss retention between composite resins, one-way analysis of variance and Tukey multiple comparisons test were used. As a result of the study, there was a difference in gloss unit of specimens produced under the same conditions. Although the degree differed depending on the composite resin, there was also a difference in gloss retention. Based on the findings, composite resins show differences in gloss due to their different characteristics. Ceram.X Sphere TEC one (CX) showing the lowest gloss retention and Estelite sigma quick (ES) showing the highest.

• 한국멀티미디어학회논문지
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• 제25권10호
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• pp.1535-1545
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• 2022

Sign language has completely different meaning depending on the direction of the hand or the change of facial expression even with the same gesture. In this respect, it is crucial to capture the spatial-temporal structure information of each movement. However, sign language translation studies based on Sign2Gloss2Text only convey comprehensive spatial-temporal information about the entire sign language movement. Consequently, detailed information (facial expression, gestures, and etc.) of each movement that is important for sign language translation is not emphasized. Accordingly, in this paper, we propose Spatial-temporal Keypoints Centered Sign2Gloss2Text Translation, named STKC-Sign2 Gloss2Text, to supplement the sequential and semantic information of keypoints which are the core of recognizing and translating sign language. STKC-Sign2Gloss2Text consists of two steps, Spatial Keypoints Embedding, which extracts 121 major keypoints from each image, and Temporal Keypoints Embedding, which emphasizes sequential information using Bi-GRU for extracted keypoints of sign language. The proposed model outperformed all Bilingual Evaluation Understudy(BLEU) scores in Development(DEV) and Testing(TEST) than Sign2Gloss2Text as the baseline, and in particular, it proved the effectiveness of the proposed methodology by achieving 23.19, an improvement of 1.87 based on TEST BLEU-4.

• 펄프종이기술
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• 제34권4호
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• pp.16-21
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• 2002

It was observed that drying temperature and curing time in the paper coating process as well as Tg of the latex used as a binder, greatly affected the properties of the coated paper such as roughness, paper and print gloss, K & N ink drop, and ink set-off. The higher drying temperature induced faster water evaporation and change in binding density, which caused an increase in paper roughness, ink gloss and ink set-off, but decrease in paper gloss and K & N ink drop. The increased curing time promoted latex filming and redistribution of the binder in coating layer. This increased pick strength and ink gloss, but decreased ink trapping. Finally, the higher Tg of the latex showed the wider changing range of these properties.

• The Journal of Advanced Prosthodontics
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• 제16권3호
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• pp.174-188
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• 2024

PURPOSE. The purpose of this study was to investigate the effects of surface treatments, liquids, and aging on color, translucency, and surface properties of monolithic ceramics. MATERIALS AND METHODS. Lithium disilicate (LDS) and zirconia-reinforced lithium silicate (ZLS) ceramics (n = 135 each) were cut and divided into three groups [crystallization+glaze (single stage), crystallization-glaze (two stages), and crystallization-polish (two stages)]. One sample from each group was examined using scanning electron microscopy (SEM). Remaining samples were divided into four subgroups (distilled water, coffee, grape juice, and smoothie) (n = 11 each), stored for 12 d in the respective liquids, and thermally aged. One sample from each subgroup was analyzed using SEM. The color, gloss, and roughness values of the samples were analyzed after surface treatment (initial) and storage under different liquids+aging conditions. The initial data and both the aged data and data change values were analyzed using robust two- and three-way analyses of variance. RESULTS. The glazed groups exhibited smoother surfaces. Ceramic type and ceramic-surface treatment interactions affected the initial translucency parameter (TP) (P < .001) and the initial and aged roughness values (P ≤ .001). Surface treatment type affected the color change (P < .001), and ceramic type affected the aged TP values (P < .001). Type of ceramic, surface treatment, and their interactions affected both the initial and aged gloss (P ≤ .001) and TP change values (P ≤ .015). Surface treatment type and ceramic-surface treatment interactions affected the gloss change values (P ≤ .001). CONCLUSION. Although both ceramics and all surface treatments are clinically applicable, crystallization-glaze is recommended. When gloss and smoothness are important or when translucency is important, ZLS or LDS may be preferred, respectively.

• 접착 및 계면
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• 제15권3호
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• pp.116-122
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• 2014

자외선 경화법을 이용한 강판의 표면 코팅 시 사용되는 올리고머, 단량체, 광개시제 및 강판의 특성 등 주요 인자가 코팅 표면의 $20^{\circ}$ 및 $60^{\circ}$ 광택도(ASTM D523)에 미치는 영향에 대해서 연구하였다. 공정 변수에 대한 광택도의 변화는 $60^{\circ}$ 광택도에 비해 $20^{\circ}$ 광택도가 민감하게 변화하였다. 단독으로 올리고머를 사용할 경우의 경우, 광택도의 변화는 거의 없었으나, 올리고머의 혼합 비율이, 단량체의 종류와 혼합 비율, 올리고머와 단량체의 혼합 비율, 개시제의 종류와 함량 비, 강판의 종류는 광택도에 큰 영향을 주었다. 올리고머 혼합의 경우 폴리우레탄 아크릴레이트(UA)와 에폭시 아크릴레이트(EA)의 혼합 비율이 70 : 30, 단량체의 경우 트리메틸올프로판트리아크릴레이트(TMPTA)와 테트라히드로퍼퍼릴아크릴레이트(THFA)가 5 : 5의 비율로 혼합된 경우가, 혼합 올리고머(UA : EA = 70 : 30)의 함량이 90 wt%인 경우 최대의 광택도를 나타내었다. 광개시제 중 액체 타입인 Darocur MBF가 고체 타입인 Irgacure 184에 비해 우수한 광택도를 나타내었으며, 최소 투입량인 1 wt%의 농도에서 높은 광택도를 나타내었다. 기질의 경우, EG강판이나 primer가 처리된 강판에 비해 GI강판이 더 좋은 광택도를 보여주었다. 상기 공정 변수에 대한 연구를 통해 광택도 향상을 위해 사용되는 첨가제 없이도 $20^{\circ}$ 광택도 95 GU의 최대값을 $60^{\circ}$ 광택도는 120 GU의 광택도를 얻을 수 있었다.

• 펄프종이기술
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• 제34권1호
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• pp.37-45
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• 2002

The effect of soft nip calendering variables including pressure, temperature, nip residence time and sheet moisture on the properties of coated papers was investigated. The change of gloss, opacity, bulk and brightness were determined after calendering. Increase of calendering pressure and temperature increased gloss, but it decreased opacity, bulk and brightness of coated papers. Nip residence time and sheet moisture content showed similar effects on these properties. Calendering conditions of 16$0^{\circ}C$ of temperature, 146kg$_{f}$/cm of line load or less were found to provide optimum conditions to obtain reasonable gloss and smoothness while minimizing the loss of bulk and opacity for coated papers.

• 접착 및 계면
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• 제13권4호
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• pp.171-181
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• 2012

본 연구는 도자기 복원용 에폭시수지 12종을 대상으로 복원제로서의 요구 특성(내구성, 가공성, 광택특성, 수축 팽창특성)을 조사한 후, 이를 통해 효과적인 재료 선택의 기준을 제시하고자 하였다. 내구성 분석결과 액상형은 비교적 손상 정도가 적고 재질 강도가 높은 도자기 유물에, 페이스트형은 상대적으로 손상 정도가 심하고 재질 강도가 약한 토기 유물에 적용하는 것이 보다 효과적이다. 가공성 분석결과 액상형은 페이스트형보다 높은 표면경도를 보였고, 액상형 중에서는 일반경화형이 속경화형보다 표면경도가 높았다. 따라서 높은 표면경도로 재가공이 어려운 액상형은 향후 첨가제 혼합을 통한 물성 개선이 필요하다. 광택특성 분석결과 외관상 무색투명한 액상형이 페이스트형보다 높은 광택도를 보였고, 액상형 중에서는 일반경화형이 속경화형보다 광택도가 높았다. $700^{\circ}C$ 연질토기는 페이스트형 중 CDK-520A/520B와 Araldite SV 427-2/HV 427-1이, 청자와 백자는 액상형 중 Devcon 5 minute과 EPO-TEK 301-2, 페이스트형 중 Quik Wood가, 분청사기는 페이스트형 중 Quik Wood, 액상형 중 EPO-TEK 301-2와 Devcon 5 minute이 대상 도자기의 광택도에 가장 근접하였다. 수축 팽창특성 분석결과 에폭시수지의 대부분은 경화 중 부피 변화가 발생하였으므로, 수축 팽창률에 따른 복원면의 증감을 사전에 예측하여 형태복원 범위를 설정하여야 한다.

• 펄프종이기술
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• 제34권1호
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• pp.12-21
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• 2002

The effect of soft nip calendering variables including pressure, temperature, nip residence time and moisture on newsprint properties was investigated. The change of bulk, opacity, smoothness, and gloss were determined. It was found that the influence of calendering pressure and temperature are more significant compare the Influence of sheet moisture content and nip residence time on newsprint properties. Calendering conditions of 16$0^{\circ}C$ of temperature, 78kg$_{f}$/cm of line load and 4ms of nip residence time were considered to be optimum conditions to obtain reasonable gloss and smoothness while minimizing the loss of bulk and opacity for newsprint.

• 한국표면공학회지
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• 제47권6호
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• pp.335-340
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• 2014

This study selected an outdoor RCD'S and verified behavior of change in the housing with time. Weathering tests were carried out as outdoor exposure test (90 degrees, 37 degrees) and laboratory test (xenon lamp), and the results were evaluated based on color difference, gloss, contact angle, and optical microscope. This study can provide basic data for standardization of development and performance evaluation on RCD'S housing products.

• 보존과학회지
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• 제27권4호
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• pp.415-420
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• 2011

금속 유물의 부식 방지를 위하여 우레탄 코팅제를 제조하였다. 제조된 우레탄 코팅제를 이용하여 그 동안 금속유물 코팅제로 주로 사용된 아크릴계 코팅제의 광택성과 코팅 후에 나타나는 변색 등의 문제점을 해결하고자 하였다. 이를 위하여 합성된 우레탄 코팅제는 아크릴계의 코팅제보다 광택이 낮고 색상 변화가 적도록 제조하였다. 이 코팅제는 기존의 코팅제에 비하여 얇은 코팅 층을 형성하면서도 우수한 접착력을 나타내었으며, 다양한 주위 환경에 의해 나타나는 금속 유물의 표면 산화에 대한 저항력과 표면에서의 발수력이 우수하였다. 또한, 아세톤, 톨루엔, 자일렌 등의 유기용매에 쉽게 용해되는 가역성이 우수한 결과를 나타내고 있어 기존의 아크릴계 금속 유물 코팅 재료를 대체할 수 있는 안정적인 코팅제로 사용할 수 있을 것으로 판단된다.