• Title/Summary/Keyword: lighting intensity

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Changes in nocturnal insect communities in forest-dominated landscape relevant to artificial light intensity

  • Lee, Hakbong;Cho, Yong-Chan;Jung, Sang-Woo;Kim, Yoon-Ho;Lee, Seung-Gyu
    • Journal of Ecology and Environment
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    • 제45권4호
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    • pp.218-227
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    • 2021
  • Background: Artificial light at night has recently been identified as a major factor adversely affecting global insect diversity. Here, we compared the insect diversity in Gwangneung Forest Biosphere Reserve, specifically in the Korea National Arboretum (with no artificial light at night), with that of three nearby urban sites with a gradient of artificial light at night (five locations at each site). We analyzed the effects of the artificial night lighting index, mean annual temperature, and field light intensity (lux) at night on the insect community structure. Results: The urban sites generally exhibited higher species richness and abundance as well as clear indicator species compared with the control site. The size distribution of the collected insects markedly differed between the control and the three urban sites. The abundance of herbivorous and omnivorous insects increased and decreased, respectively, with the increase in light intensity. Species richness of herbivorous and omnivorous insects was likely correlated with the field light intensity at night and artificial night lighting index, respectively. Conclusions: This study demonstrates the association between nighttime environment and marked changes in insect community structure and revealed consequent transition of ecosystem services by changes in trophic group composition.

다양한 조명 환경에 강인한 실시간 얼굴확인 기법 (Robust Real-time Face Detection Scheme on Various illumination Conditions)

  • 김수현;한영준;차형태;한헌수
    • 한국지능시스템학회논문지
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    • 제14권7호
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    • pp.821-829
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    • 2004
  • 얼굴인식기술이 인증 및 보안을 위한 도구로 활용되고 있지만 입력영상의 상태, 즉 조명환경에 따라 적용할 수 있는 범위가 제약적일 수밖에 없다. 본 논문에서는 이러한 제약을 최소화하기 위해 측면과 후면조명 등의 불규칙한 조명환경에서 획득한 입력영상에서 얼굴의 특징을 구분하여 얼굴영상임을 확인하는 방법을 제안한다. 제안된 방법은 에지차영상을 얼굴특징이 두드러지도록 전처리한 후, X와 Y축의 프로파일을 이용하여 얼굴영역을 예측하고 영역 내의 밝기분포를 이용하여 눈, 코, 입 등의 얼굴특징이 놓일 수 있는 수평영역을 분리한다. 수평영역들은 눈, 코, 입을 포함할 수 있는 영역의 그룹으로 나누어지고 각 그룹에서 코와 입, 그리고 눈의 순서로 특징들을 검출한다. 얼굴여부는 검출된 특징들의 구조적인 관계를 검증하여 확인한다. 제안된 알고리즘은 배경색상이나 조명의 방향과 색상 등으로 인해 얼굴의 형태와 특징이 결여된 입력영상에서도 매우 안정적으로 적용됨을 실험을 통해 확인하였다.

지능형 LED 점등시스템을 위한 점등제어 알고리즘 설계 (Design of Lighting Control Algorithm for Intelligent LED Lighting System)

  • 홍성일;인치호
    • 전기전자학회논문지
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    • 제16권3호
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    • pp.274-282
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    • 2012
  • 본 논문에서는 지능형 LED 점등시스템을 위한 점등제어 알고리즘 설계를 제안한다. 제안하는 점등제어 알고리즘은 각각의 센서노드에서 감지된 환경정보를 데이터 버스를 통해 MCU에 전송한다. MCU의 제어 소프트웨어는 설정된 제어방식에 따라 신호 값을 이용하여 조광레벨을 계산하고 결과를 비교하여 레벨유지를 결정하도록 설계하였다. 또한 LED 조명기기에 점등제어 알고리즘을 이용하여 완전대칭 되는 패턴생성에 의하여 회전 및 반전 기법을 주기적으로 교차 수행하여 점등되도록 설계하였다. 본 논문에서 제안한 점등제어 알고리즘은 안정적으로 점등제어를 하는 시스템을 설계하여 전송 데이터의 신뢰성을 높이고 91%의 이벤트 전달 비율을 유지하였다. 또한, 조명기기의 광속은 32% 감소되었고 소비전력은 49% 감소되었으며 발열량은 32% 감소되었다. 결과적으로 LED의 수명은 50% 증가되어 에너지 효율성을 향상할 수 있었다.

감성조명 시스템을 위한 색온도 조정 가능한 LED 조명 (An LED Lighting with Varying Color Temperature for Emotional Lighting Systems)

  • ;김훈;김희준
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 학술대회 논문집 정보 및 제어부문
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    • pp.522-523
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    • 2008
  • This paper presents an LED lighting which can control its color temperature. It consists of a power factor correction (PFC) circuit, an LED driver, and an LED color control circuit. The proposed system can adjusts the light intensity to obtain a desired color with independently changeable illuminance. The power factor of the PFC circuit is 98%. The LED driver has 90% efficiency at 300mA output current. The output power of the experimented LED lighting is 150 W. The achieved color temperature range was from 3000K to 7500K, and the illumination one was from 500 lux to 1500 lux.

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사무공간에서 효율적인 조광제어시스템 적용을 위한 주광분포 연구 (A study on daylight distributions for applying effective daylight responsive dimming systems in offices)

  • 김가영;최안섭
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2005년도 춘계학술대회논문집
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    • pp.123-128
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    • 2005
  • This study purposes to increase the energy-saving effects by reducing excessive intensity of radiation of artificial lighting through analyzing daylight incident A photosensor sends amounts of detected luminous flux to digital control unit(DCU) as a signal and then, it can decide dimming ratios, received a proper dimming signal from DCU. Generally it Is effective to control artificial lighting with the different control ratio of each row by setting a photosensor as same numbers and rows as artificial lighting. However, it is ineffective to do in initial costs of systems aspect in offices. As a result of grasping the distribution of daylight previously, we can dim different dimming ratios to each row of artificial lighting by a single photosensor.

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도시공원 야간 이용자 안전을 위한 경관 조명 시뮬레이션 비교 연구 (A Study on the Comparison of Landscape Lighting by Using Simulation Approach for Users' Safety in Urban Park)

  • 이종성
    • 대한안전경영과학회지
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    • 제12권1호
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    • pp.43-50
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    • 2010
  • The purpose of this study is to propose a simulation approach which compares lighting quality of each luminaire type for small urban park users' safety. For improving illumination quality, lighting intensity distribution of a luminaire is one of the important factors and it is also important to set the luminaire to a proper position. To achieve the best plan for illumination, it is most important to communicate the plan with designers of park and professional engineers in depth and the communication continues from the beginning of the plan.

환경모니터링 센서가 집적된 LED 조명용 광학시트 제작 (Fabrication of Optical Sheet for LED Lighting with Integrated Environment Monitoring Sensors)

  • 최용준;이영태
    • 반도체디스플레이기술학회지
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    • 제12권3호
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    • pp.35-39
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    • 2013
  • In this paper, we developed an optical sheet for LED lighting with integrated $CO_2$ gas and temperature sensor which can monitor at the indoor environment. The optical sheet for LED lighting is fabricated through PMMA(Polymethyl methacrylate) injection process using mold. This research enables to fabricate the reflective sheet, light-guide plate and the prism sheet in a optical sheet. The fabricated sheet demonstrates higher intensity of optical efficiency compared with single-sided sheets. The $CO_2$ sensor was fabricated using NDIR(NON-Dispersive Infrared) method and it has $0.0235mV/V{\cdot}PPM$ sensitivity. The temperature sensor was fabricated using RTD(Resistance temperature detector) method and it has $0.563{\Omega}/^{\circ}C $sensitivity.

광센서 조광제어시스템의 효율적인 조광율 결정을 위한 실험 데이터 분석 (Analysis of experimental data on daylight responsive dimming system performance for determining on effective dimming ratio)

  • 김가영;최안섭
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2005년도 학술대회 논문집
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    • pp.167-172
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    • 2005
  • This study based on the experimental data on the daylight responsive dimming systems performance. The purpose of this study increases the energy-saving effects by reducing excessive intensity of radiation of artificial lighting through analyzing incident daylight. The photosensor sends amounts of detected luminous flux to digital control unit(DCU) as a signal and then, it can decide dimming ratios, by received a proper dimming signal from DCU. Generally it is effective to control artificial lighting with the different control ratio of each row by setting a photosensor as same numbers and rows as artificial lighting. However, it is ineffective to do in initial costs of systems aspect in offices. By analyzing the data of this performance and finding regular ration between photosensors. we will execute different dimming ratios to each row of artificial lighting by a single photosensor.

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인공광을 이용한 접목표 활착촉진 시스템의 시작품 설계 - 활착촉진 시스템 내의 기온과 상대습도 분포에 미치는 기류속도의 효과 (Design of a Prototype System for Graft-Taking Enhancement of Grafted Seedlings Using Artificial Lighting - Effect of air current speed on the distribution of air temperature and relative humidity in a graft-taking enhancement system)

  • 김용현
    • Journal of Biosystems Engineering
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    • 제25권3호
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    • pp.213-220
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    • 2000
  • Grafting of fruit-bearing vegetables has been widely used to increase the resistance to soil-borne diseases, to increase the tolerance to low temperature or to soil salinity, to increase the plant vigor, and to extend the duration of economic harvest time. After grafting, it is important to control the environment around grafted seedlings for the robust joining of a scion and rootstock. Usually the shading materials and plastic films are used to keep the high relative humidity and low light intensity in greenhouse or tunnel. It is quite difficult to optimally control the environment for healing and acclimation of grafted seedlings under natural light. So the farmers or growers rely on their experience for the production of grafted seedling with high quality. If artificial light is used as a lighting source for graft-taking of grafted seedlings, the light intensity and photoperiod can be easily controlled. The purpose of this study was to develop a prototype system for the graft-taking enhancement of grafted seedlings using artificial lighting and to investigate the effect of air current speed on the distribution of air temperature and relative humidity in a graft-taking enhancement system. A prototype graft-taking system was consisted by polyurethane panels, air-conditioning unit, system controller and lighting unit. Three band fluorescent lamps (FL20SEX-D/18, Kumho Electric, Inc.) were used as a lighting source. Anemometer (Climomaster 6521, KANOMAX), T-type thermocouples and humidity sensors (CHS-UPS, TDK) were used to measure the air current speed, air temperature and relative humidity in a graft-taking system. In this system, air flow acted as a driving force for the diffusion of heat and water vapor. Air current speed, air temperature and relative humidity controlled by a programmable logic controller (UP750, Yokogawa Electric Co) and an inverter (MOSCON-G3, SAMSUNG) had an even distribution. Distribution of air temperature and relative humidity in a graft-taking enhancement system was fairly affected by air current speed. Air current speed higher than 0.1m/s was required to obtain the even distribution of environmental factors in this system. At low air current speed of 0.1m/s, the evapotranspiration rate of grafted seedlings would be suppressed and thus graft-taking would be enhanced. This system could be used to investigate the effects of air temperature, relative humidity, air current speed and light intensity on the evaportranspiration rate of grafted seedlings.

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초정압방전램프(UCD)와 나트륨램프를 적용한 식물재배에 관한 연구 (A Study on the Plant Cultivation by comparing Ultra Constant Discharge (UCD) Lamp lighting and Hi-Pressure Sodium Lamp lighting)

  • 정풍기;김영철;양현수
    • 한국기계기술학회지
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    • 제13권1호
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    • pp.31-40
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    • 2011
  • This study was conducted to research how UCD(Ultra Constant Discharge) lamp lighting affects plant cultivation. To get the results within a short time, lettuce seedling was selected as a plant and nutrient hydroponic beds were used in a dark room for 100% artificial lighting. Two beds were installed for same distance lighting condition with UCD lamp and Hi-pressure Sodium lamp each and another two beds were installed for same light intensity condition with each type of lamp. After 15 days of cultivation, for both conditions, the yields under UCD lamp were weighed more than that under Hi-pressure Sodium lamp. The result can be analyzed that the spectrum of UCD lamp having near sunlight characteristic is much superior to that of Hi-pressure Sodium lamp having a line spectrum characteristic on yellow and red wavelengths for plant cultivation.