• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기물성,응용부문
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• pp.261-263
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• 2004

This paper studies the lighting pattern control of a high-brightness LED warning light. The driving circuit for the warning light is composed of a full-wave rectified circuit and of a control circuit using a micro-controller (AT89c2051). The micro-controller is programmed in a suitable manner to accomodate a number of variable lighting patterns and to adjust the blinking speed. To reduce the total number of LEDs installed a special consideration is made to the bundled pattern in a lamp module which is lit simultaneously. The resultant LED warning light has merits not only over the conventional incandescent warning light on the energy saving aspect but also over some other LED-type ones in the market.

• 교육시설 논문지
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• 제18권2호
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• pp.3-14
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• 2011

This study aims to identify differences and lessons in eco-school planning techniques and sustainable design methods by analyzing comparatively green building certification system and the cases of sustainable schools in US, Korea and Japan. As a result of the comparative analysis, green building certification system for school facilities, both domestic and international, is categorized into external environment, energy, materials and resources, and indoor environment. From the case study, it is common that roof garden and biotopes are installed for external environment, while energy saving, passive energy utilization methods for natural lighting and ventilation such as arrangement planning, courtyard, top-light, shading devices, solar panel and insulation by roof garden are most frequently used. Also, storm water uses, water saving equipment and sustainable materials are often introduced for resource savings. Concerns for indoor environment is frequently addressed by introducing natural light and ventilation in the buildings, which makes ultimately a comfortable space.

• 한국태양에너지학회 논문집
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• 제22권4호
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• pp.26-34
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• 2002

Daylighting in building is very important as it has an effect on work performance as well as on their visual health. It is also regarded as a good energy conservation measure in saving energy used for lighting. There are many daylighting evaluation tools such as empirical equations, tables, nomograms, diagrams, protractors, computer simulation, scale models. This study conducted initial daylight measurements to analyze luminous environment in classrooms of elementary school and comparative analysis on three daylighting evaluation tools, such as daylight factor calculation formula, the graphic method with BRE Protractor and computer simulation with Adeline 3.0. It is found that the computer simulation tool produced the closest result to actual measurements of luminous environment in elementary school classroom, and the other simplified tools made appropriate results so that they can be used in the early stage of daylighting design process.

• 한국산학기술학회논문지
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• 제13권4호
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• pp.1419-1426
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• 2012

KNU 식물공장 모델의 냉난방 에너지 부하를 DesignBuilder를 이용하여 해석하였다. 실내설정온도, LED 보광주기, LED 보광량, 유리외피의 구조에 따른 에너지 소모량을 분석하였다. LED 보광이 없는 식물공장의 실내설정온도를 상추의 적정 생육온도인 $20^{\circ}C$를 중심으로 $15^{\circ}C$, $25^{\circ}C$로 변화시키면서 일정온도로 유지하는데 필요한 연간 냉난방부하를 분석하였다. $15^{\circ}C$일 때 냉방부하, $25^{\circ}C$일 때 난방부하가 가장 크게 나타났다. 상추 재배에 필요한 LED 보광 적용 시 난방부하는 감소하지만 냉방부하가 약 6배 증가한다. 또한 LED 보광 시 주간보다는 야간보광이 냉난방부하 감소에 유리한 결과를 주었다. 식물공장 외피가 냉난방부하에 미치는 영향을 비교하기 위하여 다섯 가지 종류의 외피를 적용하여 계산하였다. 이중창호의 열관류율이 작을수록 식물공장의 난방부하는 감소하고 냉방부하는 증가하였다. 재배할 작물의 적정생장온도 설정, LED 및 재배설비의 내부발열량에 따른 적절한 외피선택, 다양한 패시브 및 액티브 에너지 절감기술의 적용으로 냉방부하를 감소시키는 것이 식물공장 운영에 중요한 요소로 판단된다.

• 원예과학기술지
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• 제33권3호
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• pp.349-355
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• 2015

Lisianthus (Eustoma grandiflorum) is relatively sensitive to temperature and light conditions. For year round production of good quality potted plants and energy saving, it is necessary to understand the growth and flowering response to the combined conditions of these environmental factors. This study was conducted to examine the growth and flowering responses to temperature, photoperiod, and light intensity during the post-seedling stage. 'El Paso Deep Blue' lisianthus plants with four true leaf pairs were grown in growth chambers maintained at average daily temperatures (ADT) of 14, 20, and $26^{\circ}C$ and provided with three photosynthetic photon fluxes [PPF; 100, 200, and $400{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$] for 8 (08:00-16:00) and 16 hours (08:00-24:00) by fluorescent and incandescent lamps, resulting in four daily light integrals (DLI): about 3, 6 (two photoperiods), 12 (two photoperiods), and $24mol{\cdot}m^{-2}{\cdot}d^{-1}$. After treatment for three weeks followed by growth for one week in a greenhouse of $20{\pm}3^{\circ}C$, growth and development were measured. Higher temperature, higher PPF, and longer photoperiod promoted plant growth and flowering; however the impacts of PPF and photoperiod were smaller than those of temperature. As ADT and DLI increased, the number of leaves, number of flowers, lateral shoot length, and shoot dry weight increased. An increase of about $1mol{\cdot}m^{-2}{\cdot}d^{-1}$ DLI could constitute an increase of 0.40 to $0.76^{\circ}C$ ADT depending on these crop characteristics when ADT and DLI are above $20^{\circ}C$ and $12mol{\cdot}m^{-2}{\cdot}d^{-1}$, respectively. Therefore, growers can select a regimen of heating or supplemental lighting without delaying harvesting time or decreasing crop quality.

• 한국실내디자인학회논문집
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• 제21권3호
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• pp.194-202
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• 2012

The purpose of this study is to extract environment-friendly planning elements to apply in Korea by putting together and reclassifying four foreign environment-friendly certification systems related to regeneration spaces - LEED in USA, CASBEE in Japan, BREEAM in England and BEAM in Hong Kong - and analyze and evaluate domestic and foreign spaces which were certified as Environment-friendly spaces in order to offer plan guidelines to raise awareness of the importance of environment-friendly elements in regeneration spaces and to encourage them. The concept and the characteristics of green building were studied through documentary survey. In addition, green certification system of the present domestic new spaces and foreign regeneration spaces was studied and assessment tools for indoor regenerated spaces-related green certification system were developed. With checklists which are developed in this study, level of going green of foreign spaces certified environment-friendly was assessed. Based on the results of this study, conclusions are as follows. As a result of case research of spaces-certified green of Hong-Kong's existing buildings with a developed checklist, application of general assessment part was all alike, but that of detailed assessment part was different. However, Hong Kong showed superiority in lighting energy saving, separate collection of recyclable domestic waste, recycling by-product and management. In addition, Hong Kong applied eco-friendly planning elements maintaining buildings in their condition as possible as it could with management, use of green program, replacement with high efficiency lighting, monitoring system, installation of recycling bins and energy saving by attaching reflective film.

• Journal of Biosystems Engineering
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• 제24권1호
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• pp.19-24
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• 1999

Motivated by the need for developing the more efficient lighting system for light culture of strawberries in the greenhouse, this paper aims at acquiring and suggesting more concrete and scientific foundation of illuminating position, numbers of light source by investigating the types of lighting system and illumination distribution in the greenhouse for light culture of strawberries. The results of investigation and experiment are summarized as following below: 1. The types of lighting system used in the greenhouse producing strawberries were classified as 1 line and 2 lines lighting system. 2. As for the arranging types of artificial light, 2 lines lighting system, were classified as Z-type, N-type and W-type. (Refer Fig. 3) 3. The results of illumination distribution for Z-type, N-type and W-type of 2 lines illuminating system in the greenhouse with a small size tunnel measured at the height of 1.5m from the ground with 220V, 100W lamp in 6m light gap showed that maximum illuminance are 961x, 1211x, 1251x, minimum illuminance are 4.41x, 4.71x, average illuminance are 33.71x, 43.11x, 44.51x and standard deviations are 28.31x, 35.41x, 38.31x at each types. 4. Proportion of the area below optimal illuminance to floor area at the two lines illuminating system of Z-, N-, and W-type in greenhouse were appeared as 39.4%, 26.0% and 26.3%, respectively. Also proportion of the area over optimal illuminance to floor area at the two lines illuminating system of Z-, N-, W-type in greenhouse were appeared as 16.8%, 14% and 14.7%, respectively. Thus N-type was superior to the others from the view points of optimal illumination distribution and energy saving.

• 한국조명전기설비학회지:조명전기설비
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• 제8권4호
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• pp.38-45
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• 1994

본 논문에서는 신호감쇄 및 연집잡음(burst noise)이 존재하는 전력선 반송 채널에서 디지틀 데이터를 복조하기 위한 BPSK(Binary Phase Shift Keying) 복조기의 설계에 대하여 논한다. 이러한 BPSK 복조기의 실현에 있어서 반송파 동기호로는 소형화 및 안정화가 요구되며, 입력주파수의 변동에 대해서 낮은 위상 오차가 필요하게 된다. 이와 같은 요구조건을 만족하기 위해서 본 논문에서는 반송주파수가 10.4[kHz]이고, 전송속도가 110[bps]인 재변조방식의 BPSK 복조기를 설계 제작하였다. 설계 제작한 반송파 동기회로는 기존의 아날로그 소자로 구성되었던 승산기(multiplier) 및 지연회로를 PLL(Phase Locked Loop) IC로 대치하여 소형화 및 안정성을 확보하였으며, PLL회로 설계시에 주위온도 등을 고려하여 주파수 인입범위를 $\pm$4[kHz], 정상위상오차를 $\pm$60로 설정하였다. 기능시험 결과로부터, BPSK 복조기의 동작기능은 정상상태에서 설계조건에 만족함을 알 수 있었다.

• 한국정보통신학회논문지
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• 제9권4호
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• pp.792-797
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• 2005

본 논문에서는 전력선 통신과 조광 기술을 기반으로 에너지 절약과 적정 조도의 제어가 가능한 조명제어 스위치의 개발에 대하여 기술하였다. 개발된 스위치는 범용의 마이크로프로세서와 주변 전자기술을 이용하며, 하나의 마이크로프로세서로 전력선 통신과 조광기능을 구현함으로서 저가격 상용화가 가능하였다. 캐리어 주파수는 전송 데이터 길이와 신호감쇄를 고려하여 250kHz로 설정하였다. 저압선로에서 시제작품에 대한 시험결과, 본 스위치는 전력선의 길이와 부하용량의 변동에 대해 강인하게 동작하는 것을 확인하였다.

• Journal of information and communication convergence engineering
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• 제11권4호
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• pp.247-252
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• 2013

An intelligent light emitting diode (LED) dimming system is designed and implemented for energy-saving lighting systems. An LED light bulb is powered by an LED driver controlled by a microcontroller using pulse width modulation (PWM) signals. By changing the duty cycle of the PWM signals, the LED driver generates a driving current of up to 1,000 mA. The current consumption by the LED light bulb exhibits a very linear characteristic that indicates that the level of LED dimming can be finely tuned. Multiple sensors-lighting intensity and ultrasonic range sensors-are combined with the LED dimming system to realize an automatically controllable LED lighting system. The light intensity sensor is capable of sensing ambient light. The ultrasonic range sensor can detect objects from 0.15 to 5.6 m at a resolution of 0.0254 m. The collected information by the light intensity and ultrasonic range sensors is processed by the microcontroller that in turn automatically controls the brightness of the LED light bulb. The algorithm of the software for the LED dimming system is also described.