• Title/Summary/Keyword: High light

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Properties of Fire Resistant Finishing Mortar Using Fly Ash and Glass Forming Light Weight Aggregate (플라이애시와 유리 발포 경량골재를 사용한 내화 마감모르타르의 특성)

  • Song, Hun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.3 no.4
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    • pp.374-381
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    • 2015
  • This study is investigating the fire resistant finishing materials composed of fly ash and glass forming light weight aggregate has the high temperature thermal stability. High temperatures such as a fire, cementitious materials beget dehydration and micro crack of cement matrix. From the test result, developed fire resistant finishing materials showed good stability in high temperatures. These high temperature stability is caused by the ceramic binding and low thermal conductivity of glass forming light weight aggregate. Also, alkali activation reaction of fly ash and meta kaolin not showing the decomposition of calcium hydrates. Thus, this result indicates that it is possible to fire resistant finishing light weight mortars.

High efficiency deep blue and pure white phosphorescent organic light emitting diodes

  • Yook, Kyoung-Soo;Jeon, Soon-Ok;Joo, Chul-Woong;Kim, Myung-Seop;Choi, Hong-Seok;Lee, Seok-Jong;Han, Chang-Wook;Tak, Yoon-Heung;Lee, Nam-Yang;Lee, Jun-Yeob
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.486-488
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    • 2009
  • High efficiency deep blue and pure white phosphorescent organic light emitting diodes were developed using a new deep blue phosphorescent dopant, tris((3,5-difluoro-4-cyanophenyl)pyridine) iridium (FCNIr). A high quantum efficiency of 9.1 % with a color coordinate of (0.15, 0.16) at 1,000 cd/$m^2$ was obtained in the deep blue device and a high quantum efficiency of 15.2 % with a color coordinate (0.30, 0.32) was obtained in the pure white organic light-emitting diodes. The quantum efficiency of the pure white device is the best quantum efficiency value reported in the pure white device up to now.

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Intelligent Lighting Control using Wireless Sensor Networks for Media Production

  • Park, Hee-Min;Burke, Jeff;Srivastava, Mani B.
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.3 no.5
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    • pp.423-443
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    • 2009
  • We present the design and implementation of a unique sensing and actuation application -- the Illuminator: a sensor network-based intelligent light control system for entertainment and media production. Unlike most sensor network applications, which focus on sensing alone, a distinctive aspect of the Illuminator is that it closes the loop from light sensing to lighting control. We describe the Illuminator's design requirements, system architecture, algorithms, implementation and experimental results. The system uses the Illumimote, a multi-modal and high fidelity light sensor module well-suited for wireless sensor networks, to satisfy the high-performance light sensing requirements of entertainment and media production applications. The Illuminator system is a toolset to characterize the illumination profile of a deployed set of fixed position lights, generate desired lighting effects for moving targets (actors, scenic elements, etc.) based on user constraints expressed in a formal language, and to assist in the set up of lights to achieve the same illumination profile in multiple venues. After characterizing deployed lights, the Illuminator computes optimal light settings at run-time to achieve a user-specified actuation profile, using an optimization framework based on a genetic algorithm. Uniquely, it can use deployed sensors to incorporate changing ambient lighting conditions and moving targets into actuation. Experimental results demonstrate that the Illuminator handles various high-level user requirements and generates an optimal light actuation profile. These results suggest that the Illuminator system supports entertainment and media production applications.

The improvement of productivity of a photosynthetic purple bacterium, Rhodobacter sphaeroides by manipulating the photosynthetic apparatus (광합성 기구 조작을 통한 비유황 자색 광합성 세균, Rhodobacter sphaeroides의 생산성 증대)

  • Kim, Nak-Jong;Lee, Cheol-Gyun
    • 한국생물공학회:학술대회논문집
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    • 2000.04a
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    • pp.189-192
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    • 2000
  • The objective of this study was to investigate the effect of high content of light-absorbing pigments on overall photosynthetic efficiency in high density microalgal cultures. The light harvesting complex II (LHC II) regulating gene of Rhodobacter sphaeroides, photosynthetic purple bacterium, was removed to construct a mutant strain that had less pigment content. The mutant and wild type strains were cultured under various light intensity by adjusting the distance from the light source. The productivity of the mutant strain was higher at high light intensity (over 118 ${\mu}E/m^2/s$) compared with one of the wild type , and was lower at low light intensity (34 ${\mu}E/m^2/s$). Especially, the concentration of LHC II mutant strain was 56% higher at 118 ${\mu}E/m^2/s$. The reduction of per cell pigment contents in the mutant strain lessened the degree of the mutual shading and thus enhanced the overall photosynthetic efficiency.

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Mobilization of Photosystem II-Light Harvesting Complex II Supercomplexes during High Light Illumination and State Transitions

  • Nath, Krishna;Elizabeth, John;Poudyal, Roshan Sharma;Ko, Su Yeon;Lim, Woon Ki;Lee, Choon-Hwan
    • Rapid Communication in Photoscience
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    • v.2 no.1
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    • pp.18-23
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    • 2013
  • The photosystem II (PSII) light harvesting complex (LHC) consists of a variety of pigment protein complexes which are involved in structural organization and regulation of photosynthetic unit. These LHC proteins encoded by a group of Lhcb genes are essential for the structural integrity of PSII supercomplex, the channeling the excitation energy to the reaction center of PSII and its redistribution to photosystem I by state transitions. Numerous studies with the help of recent technological advancements have enabled a significant progress in our understanding on the structure of PSII-LHCII supercomplexes and their mobilization under various light conditions. Here, we present a mini-review on the latest concepts and models depicting the structure of PSII-LHCII supercomplexes and the role of Lhcb proteins in their supra-molecular organization. Also we will review on the current understandings and remaining problems involved in the mobilization of the supercomplexes during state transitions and during high light illumination for controlling light energy distribution between the two photosystems.

DETECTING A LED TRAFFIC LIGHT FOR VISIBLE LIGHT COMMUNICATION SYSTEM

  • Premachandra, H.Chinthaka N.;Yendo, Tomohiro;Yamasato, Takaya;Fujii, Toshiaki;Tanimoto, Masayuki;Kimura, Yoshikatsu
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.01a
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    • pp.476-481
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    • 2009
  • In this paper, we propose a visible light road-to-vehicle communication system at intersection as one of ITS technique. In this system, the communication between vehicle and a LED traffic light is approached using LED traffic light as the transmitter, and on-vehicle high-speed camera as the receiver. The LEDs in the transmitter are emitted with 500Hz and those emitting LEDs are captured by a high-speed camera for making communication. The images from the high-speed camera are processed to get luminance value of each LED in the transmitter. For this purpose, first transmitter should be found, then it should be tracked for each frame, and the luminance value of each LED in the transmitter should be captured. In our previous work, transmitter was found by getting the subtraction of two consecutive frames. In this paper, we mainly introduce an algorithm to detect the found transmitter in consecutive frames. Experimental results using appropriate images showed the effectiveness of the proposal

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Korean Secondary Students' Conceptions about Visible light, Ultra Violet and Infrared Ray (가시광선, 자외선과 적외선에 대한 학생들의 개념)

  • Han, Shin;Park, Tae-Yoon;Jeong, Sophia Sun Kyung
    • Journal of the Korean Society of Earth Science Education
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    • v.8 no.1
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    • pp.35-44
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    • 2015
  • The purpose of this paper is to identify the conceptions of middle school and high school students about visible light, Ultra violet(UV) and Infrared ray(IR). We administered questionnaire 40 people of middle school 3rd students and 43 people of high school 2nd students in Gyeonggi-do. Misconceptions about visible light, UV and Ir were observed in many students. The results of study are as follows: Firstly, Many students think that it is possible to see objects without visible light. The explanations given by students for the visiblity of objects in darkness indicates a heavy reliance on personal experiences. Secondly, we have confirmed that high school students well understand the fact that the object reflects the light. However, a significant number of students exhibited an eye-centered perspective of vision. Thirdly, students had a variety of ideas about the meaning of the term UV and IR. Analysis of questionnaire data indicates that many students believe that it is possible to see objects in the presence of UV light alone.

THE CONSTRUCTION METHOD OF IN-CERAM SPINELL CROWN AND ITS CLINICAL APPLICATION (In-Ceram Spinell Crown의 제작법과 임상적 응용)

  • Jo, Byung-Woan
    • Journal of the Korean Academy of Esthetic Dentistry
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    • v.6 no.1
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    • pp.18-31
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    • 1997
  • By the concerns of esthetic restoration were increased recently. many all ceramic crowns were developed. But they except In-Ceram Alumina were used only single crown. In-Ceram Alumina, developed by Dr. Sadon, was revealed to have high flexural Strength(450MPa). So it could be used not only anterior bridges but also posterior bridges. But In-Ceram Alumina was seen to be opaque, a little green color in transillumination light by high content of alumina oxide(85%). So new all ceramics with high strength and high translucence were needed. Spinell($MgAl_2O_3$) have a high melting point, high flexural strength, low heat conductivity, high light conductivity. In-Ceram Spinell offers glasslike light transmission by using the spinell cores instead of the alumina cores. And they have a high translucency like to natural tooth, an excellent margin integrity and a high strength(350MPa). The purposes of this study are 1) to know about the construction method of In-Ceram Spinell System, 2) to investigate the its clinical possibiliy through patients and literature reviews.

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High-Level Production of Astaxanthin by Xanthophyllomyces dendrorhous Mutant JH1, Using Chemical and Light Induction

  • Kim Jeong-Hwan;Chang Hyo-Ihl
    • Journal of Microbiology and Biotechnology
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    • v.16 no.3
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    • pp.381-385
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    • 2006
  • The production of astaxanthin by Xanthophyllomyces dendrorhous mutant depended on the culture conditions. Therefore, a cultivation strategy, including effective chemical and light induction, for the high-level production of astaxanthin by X. dendrorhous mutant JH1 was explored. Effective chemicals such as ethanol, acetic acid, and hydrogen peroxide, which are known inducers or precursors of astaxanthin synthesis, were investigated for their increase of astaxanthin production. Each of 1.0% ethanol, 1.0% acetic acid, and 1.0% hydrogen peroxide increased the astaxanthin concentration to 49.77 mg/l, 46.33 mg/l, and 45.61 mg/l, respectively. Among these chemicals, 1.0% ethanol showed the best effect on increasing astaxanthin concentration after 48 h of cultivation. Under 1.0% ethanol feeding condition, high light intensity (2,400 lux) stimulated astaxanthin production to 59.67 mg/l, compared with that in the dark-grown cultivation.

A Review of Wet Chemical Etching of Glasses in Hydrofluoric Acid based Solution for Thin Film Silicon Solar Cell Application

  • Park, Hyeongsik;Cho, Jae Hyun;Jung, Jun Hee;Duy, Pham Phong;Le, Anh Huy Tuan;Yi, Junsin
    • Current Photovoltaic Research
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    • v.5 no.3
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    • pp.75-82
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    • 2017
  • High efficiency thin film solar cells require an absorber layer with high absorption and low defect, a transparent conductive oxide (TCO) film with high transmittance of over 80% and a high conductivity. Furthermore, light can be captured through the glass substrate and sent to the light absorbing layer to improve the efficiency. In this paper, morphology formation on the surface of glass substrate was investigated by using HF, mainly classified as random etching and periodic etching. We discussed about the etch mechanism, etch rate and hard mask materials, and periodic light trapping structure.