• 제목/요약/키워드: light adaptation

검색결과 188건 처리시간 0.022초

광중합형 글래스 아이오노머 시멘트의 치질접착에 관한 연구 (THE ADAPTATION OF LIGHT CURED GLASS IONOMER CEMENTS TO TOOTH STRUCTURE)

  • 허승면;조영곤;문주훈
    • Restorative Dentistry and Endodontics
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    • 제21권2호
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    • pp.489-504
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    • 1996
  • The purpose of this study was to compare the adaptation to the tooth structure of five light cured glass ionomer cements (Fuji II LC. VariGlass VLC, Vitremer, Dyract and Geristore). Human, non-carious fifty extracted permanent premolars stored in normal saline were used. Class V cavity preparations were created on the buccal surfaces. The occlusal margin of each cavity was placed on the enamel and the gingival margin was placed on the cementum/dentin. The teeth were then distributed at random into five groups of 10 teeth each. Group 1: Fuji II LC, Group 2 : VariGlass VLC, Group 3 : Vitremer, Group 4: Dyract, Group 5 : Geristore. The prepared cavities were restored with one of the five light cured glass ionomer cements. The manipulation of each material was handled according to the manufacturer's instructions. All samples were placed in incubator of 100% relative humidity at $37^{\circ}C$ for 24 hours. The roots of the teeth were removed with the tapered fissure bur and the remaining crowns were sectioned buccolingually through the center of restorations. The cut interfaces were gradually hand polished on sandpapers from 300 up to 1200 grit. The adaptation at the tooth/cements interface was assessed by SEM (JSM-840A, JEOL Ltd.). The results of this study were as follows : 1. Group 2 revealed the best adaptation and groups 1, 4 and 5 revealed similar adaptation pattern to the cavity walls. Group 3 revealed the worst adaptation to the cavity walls. 2. Enamel margins showed better adaptation than dentin/cementum margins with each material except group 3. 3. The hybrid layers were observed between the glass ionomer cement and dentin in groups 2, 4 and 5.

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복합레진의 충전방법에 따른 변연접합성에 관한 주사전자현미경적 연구 (A Scanning Electron Microscopic Study for the Effect of the Filling Techniques of Composite Resin on the Marginal Adaptation)

  • 조현경;박동수;이찬영;이정석
    • Restorative Dentistry and Endodontics
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    • 제13권1호
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    • pp.139-150
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    • 1988
  • The purpose of this study was to evaluate the marginal adaptation of Class V resin restorations by the filling techniques. The cavities were filled with Heliosit$^{(R)}$ light curing composite resin system in accordance with the following three filling techniques - bulk-pack placement technique, apical to occlusal layering placement technique, and buccolingual layering placement technique. And the interface between the restoration and the tooth structure was observed with scanning electron microscope. The following results were obtained. 1. Marginal adaptation of enamel showed excellent irrespective of the filling techniques. 2. Marginal leakage of dentin was observed irrespective of the filling techniques. 3. No difference of marginal adaptation according to the filling techniques was observed in light curing composite resin.

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벼멸구 겹눈의 명적응과 암적응 효과 (The Effects of Light and Dark Adaptation upon the Compound Eye of Nilaparvata lugens)

  • Young Nam Youn
    • 한국응용곤충학회지
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    • 제34권4호
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    • pp.334-343
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    • 1995
  • 명상태와 암상태에서 벼멸구의 겹눈의 미세구조가 변화하는 것을 관찰하였다. 벼멸구의 겹눈을 암조건 혹은 광조건 하에서 최고 72시간 까지 유지하였을 경우에 비슷한 수준에서 겹눈을 절단하여 해부 현미경으로 관찰한 결고, 구조적인 면에서 서로 다른 모양을 관찰하였다. 한편, 전자현미경을 이용하여 암조건과 광조건 하에서의 겹눈의 미세구조를 비교한 결과, 단애층(palisade layer)의 넓이는 광조건하에서 암조건에서 보다 더 좁은 것을 알 수 있었다. 색소체는 암적응 상태의 눈에서는 단애층 주위에 원을 형성하고 있었지만, 감간채 주위에 밀집되어 있지는 않았다. 암적용과 광적용 상태의 눈에 있는 망막세포 내에서의 미세융모 지름은 차이가 없었으며, 수정체와 감간체의 접합 부위에 있는 색소체의 이동은 감간체의 위부분에 있은 수정체의 끝부분에서 변화가 있음을 관찰 할 수 있었다.

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실내공간의 빛 순응에 관한 연구 - 영화관과 전시공간을 중심으로 - (A Study on the Light Adaptation of Interior Space - Focused on the Space of Cinema and Exhibition -)

  • 이창윤;오인욱
    • 한국실내디자인학회논문집
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    • 제16권3호
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    • pp.111-118
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    • 2007
  • Using effective light, which is physical experiences by its control and manner of adaption, and make human to recognize the shape and give the meaning, so that approaching against perception experimental method which plays a role in basic clue, is regarded crucial highly among human sensory organ. this study consider the perception conception, its feature and necessity against eyes' adaption among human perception experimental experiences which has been discussed indifferently for inner space. Also, we looked over the problems among actual examples of inner spaces which should be considered as to adaption conception of human beings. Furthermore, this study aims at basic studying, which searching for enable to adapt in case of planning for inner space planning and distributing the quality evaluation by using effective light.

포화 저항망을 이용한 광적응 윤곽 검출용 시각칩 (A light-adaptive CMOS vision chip for edge detection using saturating resistive network)

  • 공재성;서성호;김정환;신장규;이민호
    • 센서학회지
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    • 제14권6호
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    • pp.430-437
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    • 2005
  • In this paper, we proposed a biologically inspired light-adaptive edge detection circuit based on the human retina. A saturating resistive network was suggested for light adaptation and simulated by using HSPICE. The light adaptation mechanism of the edge detection circuit was quantitatively analyzed by using a simple model of the saturating resistive element. A light-adaptive capability of the edge detection circuit was confirmed by using the one-dimensional array of the 128 pixels with various levels of input light intensity. Experimental data of the saturating resistive element was compared with the simulated results. The entire capability of the edge detection circuit, implemented with the saturating resistive network, was investigated through the two-dimensional array of the $64{\times}64$ pixels

전자무역에서의 수출채널별 제품의 신뢰도분석과 현지화전략 (An Analysis Product Trust on Export Channel and Product Adaptation Strategy in e-Trade)

  • 조원길
    • 통상정보연구
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    • 제10권4호
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    • pp.171-199
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    • 2008
  • The purpose of this study is to find out current problems facing the commodity trust of e-marketplace and export channel and product adaptation strategy in e-trade. This study will be an important benchmark to shed the light on understanding export channel and the localization adaptation strategy. The business performance of export corporations in Korea so that they will be able to build their own winning marketing adaptation strategy. This study will also obviously provide Korean export corporations having invested in foreign countries with the solid base to set up their marketing channel and localization adaptation strategy to compete with other export corporations abroad.

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Physiological response of red macroalgae Pyropia yezoensis (Bangiales, Rhodophyta) to light quality: a short-term adaptation

  • Xuefeng Zhong;Shuai Che;Congying Xie;Lan Wu;Xinyu Zhang;Lin Tian;Chan Liu;Hongbo Li;Guoying Du
    • ALGAE
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    • 제38권2호
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    • pp.141-150
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    • 2023
  • Light quality is a common environmental factor which influences the metabolism of biochemical substances in algae and leads to the response of algal growth and development. Pyropia yezoensis is a kind of economic macroalgae that naturally grows in the intertidal zone where the light environment changes dramatically. In the present study, P. yezoensis thalli were treated under white light (control) and monochromatic lights with primary colors (blue, green, and red) for 14 days to explore their physiological response to light quality. During the first 3 days of treatment, P. yezoensis grew faster under blue light than other light qualities. In the next 11 days, it showed better adaptation to green light, with higher growth rate and photosynthetic capacity (reflected by a higher rETRmax = 61.58 and Ek = 237.78). A higher non-photochemical quenching was observed in the treatment of red light than others for 14 days. Furthermore, the response of P. yezoensis to light quality also results in the difference of photosynthetic pigment contents. The monochromatic light could reduce the synthesis of all pigments, but the reduction degree was different, which may relate to the spectral absorption characteristics of pigments. It was speculated that P. yezoensis adapted to a specific or changing light environments by regulating the synthesis of pigments to achieve the best use of light energy in photosynthesis and premium growth and metabolism.

Tooth-colored Adhesive Restoration for Posterior Teeth

  • Krejci, I.
    • 대한치과보존학회:학술대회논문집
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    • 대한치과보존학회 2001년도 추계학술대회(제116회) 및 13회 Workshop 제3회 한ㆍ일 치과보존학회 공동학술대회 초록집
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    • pp.579-579
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    • 2001
  • One of the most important factors for the clinical success of adhesive posterior restorations is marginal adaptation. This property is very closely related to mechanical properties and to the shrinkage behavior of composite materials. Most of modem composite materials are light-cured. This is why the first part of this lecture will be confined to our recent research on light curing, such as plasma polymerization, LED polymerization and the power of modem halogen lamps. In the second part of the lecture the shrinkage properties such as dimensional shrinkage and shrinkage forces of different light curing materials and during different curing procedures will be discussed. Finally, in the third part of the lecture, marginal adaptation before and after loading in different cavity classes and by using different restorative techniques and curing procedures will be presented. Data will also be given on wear resistance, abrasiveness against opposing cusps and postcuring of composite materials.(omitted)

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A $160{\times}120$ Light-Adaptive CMOS Vision Chip for Edge Detection Based on a Retinal Structure Using a Saturating Resistive Network

  • Kong, Jae-Sung;Kim, Sang-Heon;Sung, Dong-Kyu;Shin, Jang-Kyoo
    • ETRI Journal
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    • 제29권1호
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    • pp.59-69
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    • 2007
  • We designed and fabricated a vision chip for edge detection with a $160{\times}120$ pixel array by using 0.35 ${\mu}m$ standard complementary metal-oxide-semiconductor (CMOS) technology. The designed vision chip is based on a retinal structure with a resistive network to improve the speed of operation. To improve the quality of final edge images, we applied a saturating resistive circuit to the resistive network. The light-adaptation mechanism of the edge detection circuit was quantitatively analyzed using a simple model of the saturating resistive element. To verify improvement, we compared the simulation results of the proposed circuit to the results of previous circuits.

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