• 센서학회지
• /
• 제29권2호
• /
• pp.75-81
• /
• 2020

We introduce a new visible light communication (VLC) method in which three-level return-to-zero (RZ) modulation is used for flicker-free transmission. In the VLC transmitter, the three-level RZ modulation ensures that the average optical power is constant; thus, a flicker-free light-emitting diode (LED) light is achieved. In the VLC receiver, a resistor-capacitor high-pass filter is used for generating spike signals, which are used for data recovery while eliminating the 120 Hz optical noise from adjacent lighting lamps. In transmission experiments, we applied this method for wireless transmission of an air quality sensor message using the visible light of an LED array. This configuration is useful for the construction of indoor wireless sensor networks for air pollution monitoring using LED lights.

• Transactions on Electrical and Electronic Materials
• /
• 제2권2호
• /
• pp.1-4
• /
• 2001

Urgency of using plasma-energy technologies in power industry, is outlined, increasing of economical efficiency, decreasing of energy consumption and decreasing of environmental pollution, are shown, scientific and technical bases for plasma-energy technologies of fuel utilisation, are designed, results of theoretical, experimental and rig investigations of processes of plasma ignition, gasification, thermochemical preparation for burning and combined processing of coals, are presented, results of realisation of plasma technologies of residual-oil-free (mazout) pulverised-coal boiler kindling, lighting of torch and stabilisation of luid slagging in furnaces with removal of fluid slag, are described.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2009년도 제38회 동계학술대회 초록집
• /
• pp.92-92
• /
• 2010

Replacing the existing illumination with solid-state lighting devices, such as light-emitting diodes (LEDs) are expected to reduce energy consumption and environmental pollution as they provide better efficiency and longer lifetimes. Currently, white light emitting diodes are composed of UV or blue LED with down-converting materials such as highly luminescent phosphors White light-emitting diodes (LED) were fabricated with multi-shell nanocrystal quantum dots for enhanced luminance and improved stability over time. Multi-shell quantum dots (QDs) were synthesized through one pot process by using the Successive Ionic Layer Adsorption and Reaction (SILAR) method. As prepared, the multi-shell QD has cubic lattice of zinc-blend structure with semi-spherical shape with quantum yield of higher than 60 % in solution. Further, highly fluorescent multi-shell QD was deposited on the blue LED, which resulted in QD-based white LED with high luminance with excellent color rendering properties.

• Korean Chemical Engineering Research
• /
• 제60권2호
• /
• pp.289-294
• /
• 2022

생활 폐수나 산업 폐수에 포함된 오일이나 해양 유출유 등은 수질오염 및 생태계 파괴 등의 심각한 환경오염 문제를 야기하고 있다. 대표적인 유수분리기술인 필터(또는 멤브레인)를 사용하는 경우에 분리막의 파울링, 낮은 처리용량 등의 기술적 제약이 있다. 본 연구에서는 원심력을 이용하여 유체내의 입자상 물질이나 밀도가 다른 액체-액체 혼합물을 분리하는 장치인 하이드로사이클론의 장점을 활용하며, 동시에 분리 효율을 증대시키 위하여 고해상도의 3D 프린팅 기술을 도입하여 스케일 다운된 마이크로하이드로사이클론을 제작하였다. 본 연구에서 개발한 마이크로하이드로사이클론을 통해 탈이온수와 올리브유로 이루어져 있는 수중유상 에멀젼을 효과적으로 분리할 수 있음을 증명하였다.

• 한국주거학회논문집
• /
• 제17권4호
• /
• pp.1-13
• /
• 2006

The purpose of the study was to identify the level of housing choice behavior by using the factors of residential satisfaction level, mobility motivation, and housing needs of potential purchasers in Bukgu New Housing Area, Ulsan. The survey used questionnaire from 326 households living in Bukgu and nearby area and analyzed using descriptive statistics. The research results showed low degree of residential satisfaction in storage space and neighborhood. The mobility motivations were improvement of physical environment improvement, education environment, walking road, view and lighting. The housing needs for indoor spaces showed to want more functional arrangement than the room size. The housing needs for outdoor spaces showed to want neighborhood environment in connection with the education or hospital facilities, the welfare facilities for pre-kindergarten children and elders and the leisure facilities. And the housing needs for facilities were floor furnishing for health, crime prevention system for safety needs, housekeeping appliance against environmental pollution, additional function for energy saving. The housing needs for common spaces showed that the residents preferred playing facilities by age group, exercise facilities, the community hall and the rest room which can do games or meetings.

• 한국주거학회논문집
• /
• 제24권6호
• /
• pp.69-79
• /
• 2013

The concept of sustainable development to preserve natural environment through economy in resources and energy is gradually distinguished since environmental problems as a series of air pollution and global warming take place now. Building occupies more than 1/3 of energy consumption in the whole world. Energy consumption of buildings caused a quick increase in the amount of energy use by air conditioning, which has a lot of effects on exhaustion of fossil energy as well as an increase in environmental load. Therefore, this research intends to suggest characteristics and direction for the designing of acclimatization's housing through the case study on acclimatization's housing. Acclimatization's housing is designed to reduce building load from the designing stage unlike green home or low-energy apartment. Also, factors which are commonly applied to acclimatization's housing are applied complexly by design strategic factors of Heating, Cooling and Lighting. The applied design factors make effects mutually and complexly. In addition, design strategy showed different priority by designing direction.

• 원예과학기술지
• /
• 제35권2호
• /
• pp.170-177
• /
• 2017

본 연구는 '거봉' 포도 재배시 야간의 빛 공해에 따른 피해를 예측하기 위하여 실시하였다. 야간 조사는 만개기부터 수확기까지 인공 광원으로 적색, 청색, 백색 램프를 사용하여 매일 오후 10시부터 오전 2시까지 4시간동안 조사하였다. 야간 조사는 생산량을 비롯하여 가용성 고형물 함량, anthocyanin, chlorophyll a 함량에 영향을 미치는 것으로 조사되었다. 무처리구의 가용성 고형물 함량은 $17.5^{\circ}Brix$로 야간에 빛을 조사한 적색광, 청색광, 백색광 처리구의 16.4, 16.2, $16.3^{\circ}Brix$에 비해 $1^{\circ}Brix$ 이상 높았으며, 과피의 anthocyanin 함량 또한 무처리구가 $4.08{\mu}g{\cdot}cm^{-2}$로 적색광, 청색광, 백색광 처리구의 3.14, 2.47, $2.82{\mu}g{\cdot}cm^{-2}$ 보다 높은 것으로 조사되었다. 반면에 chlorophyll a 함량은 무처리구가 $0.268{\mu}g{\cdot}cm^{-2}$로 적색광, 청색광, 백색광 처리구의 0.339, 0.345, $0.372{\mu}g{\cdot}cm^{-2}$와 비교하여 가장 낮았다. 결과적으로, 당의 증가와 anthocyanin의 축적 및 chlorophyll의 감소는 과실 성숙에 수반된 현상이라는 점을 고려할 때, 야간 조사는 '거봉'의 암기를 중단시켜 과실의 성숙 과정을 지연시키며 적생광 처리는 생산량 감소를 수반하였다. 따라서 광파장에 관계없이 야간조사에 의한 빛공해가 나타나는 것으로 확인되었으며, 가로등을 비롯한 야간 조명이 설치된 지역에 인접한 포도원의 경우 과실의 성숙이 불량해 질 수 있는 것으로 판단된다.

• 한국산학기술학회논문지
• /
• 제17권2호
• /
• pp.246-251
• /
• 2016

도로조명 중 누출광을 고려하지 않은 보안등이 아직도 많이 사용되어 주거지 침입광이 발생되고 있다. 이러한 도로조명의 침입광 저감을 위해 차광판이 설치되고 있지만, 효과가 미미하거나 미적 요소 및 안전성에 문제가 있다. 본 연구에서는 침입광 효율적인 저감을 위해 차광판 구조별 저감 특성을 연구하였으며, 그 방법으로 조명시뮬레이션 프로그램인 Relux 활용하였다. 또한 시뮬레이션의 값의 정확성을 알기 위해 실제 측정값과 검증하였다. 그 결과 (상)도색 글로브를 제외한 모든 차광판에서 후사광 저감 효과가 뛰어났으며, 도장형 차광판의 경우 전사광도 줄어들어 글레어 저감도 효율 적인 것으로 확인되었다. (상)도색 글로브는 위쪽으로 가는 빛을 아래로 반사시켜 후사광 전사광 모두 증가하였지만, 스카이 글로우(Sky glow) 저감에 효율적인 차광판으로 확인되었다. 시뮬레이션 값과 실측값은 90 %의 일치률을 보였다.

• KIEAE Journal
• /
• 제16권3호
• /
• pp.71-76
• /
• 2016

Purpose: This study aimed at improving the indoor environment of the office building by measuring the indoor environment and conducting a survey. Method: The measurement was conducted from January 13 to March 16 in 2012, targeting 44 sites in same office building located in Seoul, South Korea. The lists of measurement such as dry-blub temperature, relative humidity, formaldehyde (HCHO), asbestos, carbon monoxide (CO), carbon dioxide (CO2), volatile organic compounds (VOCs) and particle pollution (PM10) were measured. In addition, illuminance which belongs to light environment and noise in sound[acoustical] environment were measured respectively. Result: The buildings showed overall pleasant conditions. In terms of the thermal, air, sound, and visual environment, each measurements were satisfied with the requirements in standard, within pleasant ranges, except several sites. However, the survey results were revealed that the office workers were mostly dissatisfied with their indoor environment. Given that the measured values were mostly within standards, the results of survey might have resulted from a compensation mentality biased toward the subjects in psychological terms.

• 한국주거학회논문집
• /
• 제19권5호
• /
• pp.85-92
• /
• 2008

The aim of this research is to develop the sentiment indicators of housing welfare for evaluating housing welfare policies conducted by the Korean government. The methods of this research are used by analysis of related documents, FGI (Focus Group Interview), and survey. The survey was made by experts and consumers. To analyze the survey, this research also uses confirmatory factor analysis by SPSS (Statistical Package for the Social Science) program, AHP (Analytical Hierarchy Process) by Expert Choice program, frequency, average, percentages, Factor analysis etc. As a result of this research, selected housing welfare indicators are settled as follows: In the housing welfare aspect, 11 indicators in the department of 'Housing Satisfaction' and 11 indicators in the department of 'Community Satisfaction' (22 in total) are suggested. The indicators are 1) Water Supply and Distribution Equipment 2) Heating equipment 3) the size of the exclusive residential area 4) the number of rooms 5) Ventilation and Lighting 6) Sound Insulation (Indoor Noise) 7) Air Pollution/Odor 8) House Deposit 9) Rent Paid 10) Maintenance (Dwelling) Cost 11) The length of Occupation 12) Proximity to Welfare Facilities 13) Educational Environment 14) Convenience of Facilities (shops, hospitals etc.) 15) Convenience of Transportation and Commuting 16) Distance from Workplace 17) Landscape and Green Space (Tree, Flowers, Grass etc.) 18) Vandalism (Destruction Behavior, graffiti etc.) 19) Privacy 20) Noise in Public Places (Drinking, Loudly Talking etc.) 21) Safety from Crime 22) Safety from a Disaster. As of 2007, the housing welfare sentiment index is measured by the survey of 1,000 inhabitants in the public housing, which shows 3.51.