• Title/Summary/Keyword: light adaptation

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

  • Hur, Seung-Myun;Cho, Young-Gon;Moon, Joo-Hoon
    • Restorative Dentistry and Endodontics
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    • v.21 no.2
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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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A Scanning Electron Microscopic Study for the Effect of the Filling Techniques of Composite Resin on the Marginal Adaptation (복합레진의 충전방법에 따른 변연접합성에 관한 주사전자현미경적 연구)

  • Cho, Hyun-Kyung;Park, Dong-Su;Lee, Chan-Young;Lee, Chung-Suck
    • Restorative Dentistry and Endodontics
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    • v.13 no.1
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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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The Effects of Light and Dark Adaptation upon the Compound Eye of Nilaparvata lugens (벼멸구 겹눈의 명적응과 암적응 효과)

  • Young Nam Youn
    • Korean journal of applied entomology
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    • v.34 no.4
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    • pp.334-343
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    • 1995
  • The eyes of Nilaparvata lugens were examined for ultrastructural changes in the light and dark adapted states. Inspection of light microscope sections taken at similar levels of compound eyes from insects kept in light or darkness for periods up to 72 hors revealed some differences between light and dark adapted eyes. Using the electronmicroscope, in light adapted eyes the palisade layer was narrower than that in dark adapted eyes. The pigment granules still formed a ring around the palisade layer in the dark adapted eye but, they did not form a tight circle around the rhabdom. No constant difference was found between the diameters of the microvilli in light and dark adapted eyes. The pigment movements at the junction of the cone and the rhabdom took the effect on varying the pigment aperture at the tip of the cone in front of the rhabdom tip.

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

  • Lee, Chang-Yoon;Oh, In-Wook
    • Korean Institute of Interior Design Journal
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    • v.16 no.3 s.62
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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.

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

  • Kong, Jae-Sung;Suh, Sung-Ho;Kim, Jung-Hwan;Shin, Jang-Kyoo;Lee, Min-Ho
    • Journal of Sensor Science and Technology
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    • v.14 no.6
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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

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

  • Cho, Won-Gil
    • International Commerce and Information Review
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    • v.10 no.4
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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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    • v.38 no.2
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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.
    • Proceedings of the KACD Conference
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    • 2001.11a
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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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    • v.29 no.1
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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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