• Title/Summary/Keyword: Down light

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Comparisons of Thermal Insulations between on Air-Cell Pack Embedded Jacket and Down Jackets (공기주입형 의복의 보온력 측정 및 다운재킷의 보온력과의 비교)

  • Kim, Yung-Bin;Jang, Won;Kim, Kirim;Kim, Siyeon;Baek, Yoon Jeong;Lee, Joo-Young
    • Journal of the Korean Society of Clothing and Textiles
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    • v.39 no.1
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    • pp.55-62
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    • 2015
  • This study investigated the thermal insulation of an air-cell pack embedded jacket and down jackets to understand the potential of air-cell pack as a filler for winter outdoor wear. A thermal manikin measured the thermal insulation of the following jackets: HD (heavy down jacket, total weight (Tw) 750g, goose down weight (Dw) 350g), LD (light down jacket, Tw 560g, Dw 140g), AF (air-cell pack embedded jacket, Tw 490g, trunk goose down in LD was replaced to air cell), F (film jacket, Tw 469g, but removed the air in the air-cell pack from the AF), and Control (control jacket, Tw 438g, removed the air-cell pack film from the F). Thermal insulations of each experimental condition were measured in a static standing posture. Total thermal insulations (IT) were 1.29clo (HD), 1.23clo (LD), 1.16clo (AF), 1.20clo (F), and 1.08clo (Control). Body regional thermal insulation was higher in the chest and back than in the abdomen and hip in all conditions. The results suggest that an economical and versatile outdoor jacket with superior thermal insulation will be feasible if the air volume is properly controlled in air-cell pack embedded jackets in consideration of regional different distribution and used in combination with film and down.

LIGHT-DEPENDENT CHANGES OF CHLOROPHYLL FLUORESCENCE AND XANTHOPHYLL CYCLE PIGMENTS IN MAIZE LEAVES DURING DESICCATION

  • Xu, Chang-Cheng;Lee, Choon-Hwan;Zou, Qi
    • Journal of Photoscience
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    • v.5 no.1
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    • pp.17-22
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    • 1998
  • Changes of chlorophyll fluorescence and xanthophyll cycle pigment contents in maize leaves were investigated dunng desiccation in darkness or in the light. In darkness, a drastic dehydration of detached maize leaves down to 50% relative water content (RWC) affected photochemical efficiency of photosystem II (Fv/Fm) and pht)tochemical quenching (qP) only slightly. In contrast, desiccation in the light with a moderate intensity led to a pronounced reduction in Fv/Fm with a Fo quenching when RWC was greater than 70%. This reduction in Fv/Fm could be recovered in darkness under hutrod condition. In leaves with RWC below 70%, significant reduction in Fv/Fm was accompanied by an increase of Fo, which could not be reversed within 5 h in darkness under humid condition. The nonphotochemical quenching increased during desiccation in the light with a concomitant rise in zeaxanthin at the expense of violaxanthin. Pretreatment with dithiothreitol (DTT), an inhibitor of zeaxanthin synthesis, inhibited the development of nonphotochemical quenching and prevented the xanthophyll interconversion during desiccation in the light. These results suggest that even light with a moderate intensity becomes excessive under dehydration and zeaxanthin-associated photoprotection of photosynthetic apparatus against photodamage is involved, but the protection is not complete against severe desiccation.

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Research Trend of Quantum Light Source for Quantum Information Technology (양자 정보 기술을 위한 양자 광원 연구 동향)

  • Ko, Y.H.;Kim, K.J.;Choi, B.S.;Han, W.S.;Youn, C.J.;Ju, J.J.
    • Electronics and Telecommunications Trends
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    • v.34 no.5
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    • pp.99-112
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    • 2019
  • A quantum light source is an essential element for quantum information technology, including quantum communication, quantum sensor, and quantum computer. Quantum light sources including photon number state, entangled state, and squeezed state can be divided into two types according to the generation mechanism, namely single emitter and non-linear based systems. The single emitter platform contains atom/ion trap, solid-state defect/color center, two-dimensional material, and semiconductor quantum dot, which can emit deterministic photons. The non-linear based platform contains spontaneous parametric down-conversion and spontaneous four-wave mixing, which can emit probabilistic photon pairs. For each platform, we give an overview of the recent research trends of the generation, manipulation, and integration of single photon and entangled photon sources. The characteristics of quantum light sources are investigated for each platform. In addition, we briefly introduce quantum sensing, quantum communication, and quantum computing applications based on quantum light sources. We discuss the challenges and prospects of quantum light sources for quantum information technology.

Study on the Plant Growth Variation According to Change of Luminous Flux LED Light in Plant Factory (식물공장의 LED 광강도 변화에 따른 식물성장 변화에 관한 연구)

  • Hong, Ji Wan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.3
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    • pp.304-311
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    • 2020
  • The purpose of this study is to change plant growth according to the light quantity of LED light source and to standardize plant factories technology according to the optimal LED light range. Growth was relatively stable at the 1,400 lx and 1,600 lx intensities, and growth continued with increasing light intensity, but growth slowed down with growth without leaves (Ed- I don't understand). The growth characteristics at 400 lx to 800 lx were sustained to some extent during the experimental period, but the growth of the larvae was maintained until the 7th day and the growth of leaves was not developed. From 1,000 lx to 1,400 lx, brightness, leaf growth and daily growth increased, and the growth cycle exhibited a repeating cycle of growth and slowdown. In addition, 1,600 lx and 1,800 lx showed similar growth to that at 1,400 lx, but leaf growth was high. However, at 1,800 lx, the growth was slightly higher than at 1,400lx and it slowed down over time. In addition, the stronger the light, the higher the temperature around the plant and the greater the dryness of the leaves due to the heat emitted from the light source.

A Study on Light-Shelf System using Location-Awareness Technology for Energy Saving in Residential Space (에너지 저감을 위한 주거공간 내 위치인식기술 적용 광선반 시스템 개발연구)

  • Gim, Sanghoon;Kim, Yongseong;Lee, Henagwoo;Seo, JangHoo
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.26 no.6
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    • pp.275-286
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    • 2014
  • Light shelf is an efficient system that reduces the energy consumption by bringing the natural light down to the deep spaces inside of a building. However, the existing light shelves have limits in reducing energy usage, because the direction of the light flow is determined by the external environment such as the altitude of the sun and the azimuth. This current study presents a system that increases the efficiency of the light shelf by applying the Location-Awareness technology, in which the efficiency was verified through the performance evaluation. According to the examination of the technology for the Location-Awareness within residential space, 'Zigbee' type appears to be the most appropriate. The Location-Awareness technology operates the light shelf based on both the angle control axis and the light shelf angle control axis through the modularization of the reflector surface which is less affected by the external environment. The results of the performance evaluation showed that the movable light shelf that employs the Location-Awareness technology can reduce the energy consumption for lighting by 98.3% compared to the fixed light shelf and by 97.3% compared to the movable light shelf without Location-Awareness.

On Slimming down the Functions Room of Light Rail Transit Stations by Utilizing an Enhanced DSM Method (개선된 DSM 기법을 통한 경전철 정거장 기능실의 슬림화에 관한 연구)

  • Kim, Joo-Uk;Park, Kee-Jun;Kim, Young-Min;Lee, Jae-Chon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.2
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    • pp.927-939
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    • 2015
  • It appears that the rapid advance in technology has allowed to broaden the variety of rail systems technology, thereby fostering new business opportunity in rail industry. The direction of rail systems operations is mainly two fold. In one direction, long distance operations between mega cities are pursued with help of high speed trains under development. In the other case, relatively short distance operations for covering intra-city or suburban area are becoming popular. A good example of the latter case is light rail transit (LRT) systems. Due to the short distance operation, it is thus expected that both the development and operation cost for LRT systems be reduced to some extent. The cost reduction desired in there can be gained by scaling down the sizes of both the trains and stations as compared to those of normal rail systems. However, it is not well known how the LRT stations can be scaled down. The objective of this paper is to study on how to slim down the stations (particularly, the functions room) of LRT systems. To achieve the objective, an approach is studied based on a modified method of design structure matrix (DSM). Specifically, using the enhanced DSM method, an integrated architecture is developed for the functions room, in which equipments are housed to perform the functions of electricity, signaling, and communication for LRT stations. The use of the result indicates that the desired reduction can be obtained with the approach taken in the paper.

Natural Dyeing of Chitosan Crossinked Cotton Fabrics(III) - Amur cork tree - (키토산 가교 처리된 면직물의 천연염색에 관한 연구(III) - 황벽을 중심으로 -)

  • Kwak, Mi-Jung;Lee, Shin-Hee
    • Fashion & Textile Research Journal
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    • v.10 no.4
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    • pp.544-551
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    • 2008
  • In this study, the colorants of Amur cork tree were extracted with boiling water. Chitosan crosslinked cotton fabrics have been dyed with aqueous extract of Amur cork tree and their dyeabilities on the fabrics were studied. Additionally the fastness to washing and light were also investigated. Cotton fabrics were treated with a crosslinking agent epichlorohydrin in the presence of chitosan to provide the cotton fabrics the dyeing properties of natural dye(Amur cork tree) by the chemical linking of chitosan to the cellulose structure. This process was applied by means of the conventional mercerizing process. The chitosan finishing and durable press finishing of the cotton fabrics occurred simultaneously in the mercerization bath. On the surface color change, the fabric of no-chitosan finished and no-mordanted has greenish yellow. The more crosslinked chitosan on cotton fabrics has the more turned down greenish on the surface color, as increasing the concentration of chitosan, greenish color turn down to the yellow close the 90o hue angle. In all sorts of fabrics, dyeability(K/S) is slightly affected by the number of manufacturing process and the concentration of chitosan. But only mercerized cotton fabric has higher dyeability (K/S) than mordant treated cotton fabrics. Wash fastness has little different results by each condition, but almost similar values. Light fastness was improved with chitosan treatment on cotton fabric.

3D image processing using laser slit beam and CCD camera (레이저 슬릿빔과 CCD 카메라를 이용한 3차원 영상인식)

  • 김동기;윤광의;강이석
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.40-43
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    • 1997
  • This paper presents a 3D object recognition method for generation of 3D environmental map or obstacle recognition of mobile robots. An active light source projects a stripe pattern of light onto the object surface, while the camera observes the projected pattern from its offset point. The system consists of a laser unit and a camera on a pan/tilt device. The line segment in 2D camera image implies an object surface plane. The scaling, filtering, edge extraction, object extraction and line thinning are used for the enhancement of the light stripe image. We can get faithful depth informations of the object surface from the line segment interpretation. The performance of the proposed method has demonstrated in detail through the experiments for varies type objects. Experimental results show that the method has a good position accuracy, effectively eliminates optical noises in the image, greatly reduces memory requirement, and also greatly cut down the image processing time for the 3D object recognition compared to the conventional object recognition.

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Characteristics of Street Lamp Controller with Earth Leakage Contactor (가로등 전용 누전 개폐기의 차단효과에 대한 고찰)

  • Lee, Seong-Jae;Shin, Jae-Sik
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.06a
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    • pp.283-283
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    • 2010
  • Smart street light controller is a product with advance micro controller base for energy saving in conventional street lighting systems. Intelligent Street light controller are specially developed for automation and energy saving in conventional street light systems and lighting systems. It is so designed that it operates on sunrise & sun set timings according to longitude of particular location with facilitate to set month wise civil twilight timings to cope up with all seasons. Dimming (Power down) mode selection switch on/off at fixed times with relay or contactor. Night dimming, staggering and intelligent control reduces burn hours and increases the lifetime of lamps with about 30% and low annual operating cost type base are among the most inexpensive wireless technologies available. Low initial costs As PLC wireless, there is no need to establish cable connection.

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Solar System Sciences with SPHEREx (SPHEREx를 활용한 태양계 연구)

  • Pyo, Jeonghyun;Jeong, Woong-Seob
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.1
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    • pp.48.2-48.2
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    • 2018
  • SPHEREx is expected to provide us with the opportunity of unbiased sampling of small Solar System objects along with near-infrared ($0.75-5.0{\mu}m$) spectroscopic (R ~ 41) information. The estimated numbers of detections are tens of thousands for asteroids, thousands for Trojans, hundreds for comets, and several for Kuiper Belt Objects, Centaurs and Scattered Disk Objects. Wide spectral range covering many bands from carbon-bearing molecules and ices will enable us to systematically survey the volatile materials throughout the Solar System. SPHEREx will, for the first time, produce the near-infrared spectral map of the zodiacal light to pin-down the relative contributions of various populations of Solar System objects and interstellar dust to the dust grains in the interplanetary space. The study of the zodiacal light is also important to remove the foreground for the EBL (extragalactic background light) study, one of the main topics of the mission.

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