• 한국위성정보통신학회논문지
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• 제7권3호
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• pp.116-120
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• 2012

전 세계적으로 빌딩 에너지 세이빙에 대한 관심이 증가하고 있으며, BEMS(Building Energy Management System)을 효율적으로 운용하기 위한 IT 기술에 대한 연구를 지속적으로 진행하고 있다. 최근 LED 조명기술의 발전으로 LED를 제어하여 에너지 절감효과를 극대화 할 수 있으며 BEMS에 이러한 LED 조명 제어기술들이 개발되고 있다. 본 논문에서는 건물에 설치되어 있는 IP 카메라와 Adaptive GMM(Gaussian Mixture Model)을 이용하여 BEMS용 LED 조명제어에 대한 시스템을 제안하였다. 설계한 구조를 기반으로 빌딩의 영상을 실시간으로 모니터링하고, 동적 객체를 영상추적하며, 다수의 객체를 클러스터링하고 인체 이동을 감지하여 LED 조명을 제어하는 기능을 제안하고, 관련 Software 개발을 통해 구현가능성을 입증하였다.

• 설비공학논문집
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• 제26권6호
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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.

• 한국주거학회논문집
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• 제17권4호
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• pp.1-13
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• 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.

• Journal of Power Electronics
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• 제18권5호
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• pp.1489-1500
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• 2018

Partial shading analysis of large-scale photovoltaic (PV) arrays has recently become a theoretically and numerically challenging issue, and it is necessary for PV system designers. The main contributions of this study are the following: 1) A PSIM-based macro-model was employed because it is remarkably fast, has high precision, and has no convergence issues. 2) Three types of equivalent macro-models were developed for the transformation of a small PV sub-array with uniform irradiance to a new macro-model. 3) On the basis of the proposed new macro-model, a tearing method was established, which can divide a large-scale PV array into several small sub-arrays to significantly improve the efficiency improvement of a simulation. 4) Three platforms, namely, PSIM, PSpice, and MATLAB, were applied to evaluate the proposed tearing method. The proposed models and methods were validated, and the value of this research was highlighted using an actual large-scale PV array with 2420 PV modules. Numerical simulation demonstrated that the tearing method can remarkably improve the simulation efficiency by approximately thousands of times, and the method obtained a precision of nearly 6.5%. It can provide a useful tool to design the optimal configuration of a PV array with a given shading pattern as much as possible.

• 조명전기설비학회논문지
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• 제17권5호
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• pp.8-14
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• 2003

광센서 조광제어시스템은 실내로 유입되는 주광량에 따라 자동으로 광속량을 조절하여 설정조도를 유지시켜주는 에너지절약 시스템이다. 이 시스템의 성공여부를 결정하는 여러 요인들 중, 광센서의 측광값이 작업면 조도를 얼마나 정확히 나타내는가가 중요한 포인트가 된다. 그래서 본 연구에서는 실험을 통해 광센서의 여러 측광방향 형태를 결정하고, 각 측광방향별 광센서의 반응신호를 측정하였다. 그리고 광센서의 적절한 위치를 찾기 위해 실제공간에서 서로 다른 위치에 광센서를 설치하여, 작업면 조도와 광센서 반응신호의 관계를 측정하고 분석하였다. 분석된 결과를 토대로 광센서의 적절한 위치와 측광방향성을 제시하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.438-438
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• 2011

White light-emitting diodes (LEDs), the so-called next-generation solid-state lighting, offer benefits in terms of reliability, energy-saving, maintenance, safety, lead-free, and eco-friendly. Recently, rare-earth-doped oxynitride or nitride compounds have attracted a great deal of interest as a photoluminescent material because of their unique luminescent property, especially for white LEDs applications. Ce doped ${\beta}$-SiAlON has been studied as a wavelength conversion phosphor in white LEDs thanks to its high absorption rates, high quantum efficiency, and excellent thermal stability. Previously researches were not enough to understand the detail mechanism and characteristics of ${\beta}$-SiALON. The bandgap structures and electronic structures were not exact due to limitation of calculation methods. In this study, to elucidate the Ce doping effect on the SiAlON system, accurate band structures and electronic structure of the Ce doped ${\beta}$-SiAlON was intensively investigated using density functional theory calculations. In order to get a better description of the band gaps, MBJLDA method were used. We have found a single Ce atom site in ${\beta}$-SiAlON super cell. Furthermore, the density of state, band structure and lattice constant were intensively investigated.

• 한국인터넷방송통신학회논문지
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• 제12권1호
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• pp.181-187
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• 2012

LED는 빛을 내는 반도체 이다. 최근 친환경적 산업이 발전함에 따라 LED조명의 연구가 활발하게 진행되어 가고 있다. 특히 LED를 이용한 통신기법인 LED 통신에 대한 활발한 연구가 진행 중이다. 본 논문에서는 LED 통신을 이용한 PC-PC 전송시스템을 구현하였다. LED를 이용한 송신부 회로구성 및 PD와 OP-Amp를 이용한 수신부 회로를 구성하였다. 실험은 다음처럼 진행되었다. 송 수신부 양 끝단에 컴퓨터를 연결한 다음, 텍스트 전송프로그램을 이용하여 텍스트를 전송하였다. 이때 보드 레이트(baud rate), LED 색깔, 전송거리 등 다양한 변화를 주면서 실험을 진행하였다.

• 국제초고층학회논문집
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• 제6권4호
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• pp.297-300
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• 2017

Employers are realizing that workplaces have an immense impact on productivity. And, because people typically represent about 90% of a company's costs, even a slight improvement in productivity hits the bottom-line in a very big way. The focus is shifting away from saving money by reducing space needs or cutting energy requirements, and moving toward making the workplace friendlier and healthier. What is a healthy workplace, exactly? The answer should be clear by now. Mountains of research have expounded on this very topic, and then news outlets cover the latest discoveres ad infinitum. The problem is, research is rather dense, while the news isn't comprehensive. Office managers trying to improve workplace wellness want neither a 55-page report nor a half dozen articles to convince their landlord that their space can do better. Recognizing this gap, Harvard researchers have released a concise-yet-complete list of healthy building features. Here, we're sharing these nine features with a few insights of our own on the value of being healthy and productive. Find out: ${\bullet}$ What makes a healthy building and why is it so important ${\bullet}$ How to improve the health of your own office ${\bullet}$ What happens for your people and your bottom line when you make health a priority.

• 조명전기설비학회논문지
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• 제13권4호
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• pp.1-6
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• 1999

이 논문에서는 주유소 조명시설의 실태를 조사하고 주유소의 각 영역별 조도를 측정하여 그 결과를 KS와 IESNA의 기준과 비교하고 주유소의 전체적인 조명패턴을 분석하였다. 주유지역에 있어서 조도는 KS에 제시된 값보다 상당히 높은 반면 IESNA의 기준보다는 대체로 낮음을 알 수 있었다. 그 외의 지역 또한 조도값에 있어서 서로 많은 차이가 발생함을 확인하였다. 이러한 결과로부터 주유소 조명시설의 적절한 유지·보수에 의해 불필요한 에너지 낭비를 줄일 수 있고, 이러한 점을 고려한 설계과정의 필요함을 알 수 있었다. 또한 KS규격에 있어서 다른 나라의 기준과 비교하여 각 영역별 작업특성을 고려한 철저한 평가와 기준설정이 이루어져야 하겠다.

• 한국재료학회지
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• 제27권6호
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• pp.301-306
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• 2017

The discovery of new luminescent materials for use in light-emitting diodes(LEDs) has been of great interest, since LED-based solid state lighting applications are attracting a lot of attention in the energy saving and environmental fields. Recent research trends have centered on the discovery of new luminescent materials rather than on fine changes in well-known luminescent materials. In a sense, the novelty of our study beyond simple modification or improvement of existing phosphors. A good strategy for the discovery of new fluorescent materials is to introduce activators that are appropriate for conventional inorganic compounds, that have well-defined structures in the crystal structure database, but have not been considered as phosphor hosts. Another strategy is to discover new host compounds with structures that cannot be found in any existing databases. We have pursued these two strategies at the same time using composite search technology with particle swarm optimization(PSO). In this study, using PSO, we have tracked down a search space composed of Sr-Al-Si-O-N and have discovered a new phosphor structure with yellow luminescence; this material is a potential candidate for UV-LED applications.