• 설비공학논문집
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• 제28권9호
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• pp.343-349
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• 2016

Due to the recent increase in lighting energy consumption in buildings, there are a growing number of studies seeking solutions this problem. The effectiveness of light-shelves as natural lighting systems to solve this problem has been recognized, and various studies regarding such systems are being carried out currently. However, the lighting efficiency of light-shelves decreases if illumination intensity is low-such as at night time, and it also obstructs the views of building occupants. Therefore, the purpose of this study is to examine a movable drawer type light-shelf which allows for the width of the reflector to be adjusted and verify its performance through a simulated test-bed. The following conclusions were reached. 1) The purpose of this study is to solve the problem previously associated with the light-shelf system- of obstructed views-by responding to external environments and minimizing the width of the light-shelf at night time when the efficiency of the light-shelf declines. 2) The proper variables of the movable drawer type light-shelf which enables the width adjustment of the reflector were ascertained in this study according to four solar terms : a width of 0.6 m at an angle of $20^{\circ}$, a width of 0.4m with an angle of $20^{\circ}$, and a width of 0.1 m with an angle of $20^{\circ}$ were determined for the summer solstice, fall/spring equinoxes, and winter solstice respectively; revealing that width adjustment of the light-shelf is a significant factor. 3) The movable drawer type light-shelf which enables${\backslash}$width adjustment of the reflector suggested in this study can reduce the lighting energy consumption by 18.7% and 14.3% in comparison to previous light-shelves with a fixed width of 0.3 m and 0.6m, indicating that it is effective for saving energy.

• 한국통신학회논문지
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• 제36권11B호
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• pp.1383-1388
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• 2011

세계적으로 온실가스 감축 정책, 전기전자제품 유해물질 사용제한 지침(RoHS: Restriction of Hazardous Substances) 등 환경 규제 제도의 본격 시행으로 전통적인 조명이 친환경 고효율 LED(Light Emitting Diode)로 빠르게 대체되고 있으며, 에너지 효율의 극대화를 위한 효과적인 조명 제어 기술이 요구되고 있다. 본 논문에서는 여러 광원으로 이루어진 LED 조명 광원의 효과적인 제어를 통해 실내의 각 위치에 따라 요구되는 조도를 만족하면서 LED 조명 시스템의 에너지 소비를 개선하는 조명제어 기법을 제안한다. 실내 각 영역별 사용자 유무, 요구조도 수치 등을 반영하여 조명제어 최적화 문제를 구성하고, 이에 관한 해를 도출하여 LED 조명의 개별 광원 광도(luminous intensity)를 효과적으로 조절한다. 이를 통해 제시되는 각 위치별 요구조도를 만족하고, LED 조명 시스템 에너지 소모를 효율적으로 감소시킨다. 모의실험 결과 제안된 방식이 기존 방식 대비 사용자 실내 점유율 증가에 따라 약 40%, 조명과 피조면 사이 높이 변화에 따라 약 24~71%의 소비전력을 절감 효과를 얻음을 보인다.

• 설비공학논문집
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• 제25권1호
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• pp.14-19
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• 2013

The present study has been conducted for evaluating and comparing the performance of the underfloor air distribution system(UFAD) and the ceiling based air distribution system(CBAD) under cooling condition. Simulations and experiments were carried out for verifying the model by TRNSYS program about UFAD and CBAD. The results of simulation for various conditions of thermal load are summarized as followings. UFAD had an advantage for making thermal comfort because of lower temperature of the floor surface. Moreover, UFAD showed lower fan power about 30~50% than CBAD under the same conditions of thermal load. The energy saving rates of UFAD were increased to 17.7% in proportion to the thermal load on unoccupied zone(lighting). Ultimately, additional investigations should be done for analyzing optimized operating conditions of UFAD with considering the thermal performance of building envelop and the thermal load.

• 한국태양에너지학회 논문집
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• 제29권1호
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• pp.1-10
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• 2009

This study was carried out to evaluate the Life Cycle Cost(LCC) of three types of RTPV(Building Integrated Photovoltaic) systems-Glass plus Granite. Crystalline BIPV and See through Amorphous BIPV-which were vertically installed to generate the same power output(76 kW level). Initial investment costs. cost. savings and maintenance costs had been predicted during the period of analysing the LCC of three types of BIPV(Building Integrated Photovoltaic) systems installed for the purpose of evaluating the LCC. In case of cost savings, it had been analyzed by measuring the amount of electric power generated, reduction in lighting load and heat & cooling loads through simulation. From this analysis, it was predicted that the See-through amorphous BIPV offering cost saving advantages demonstrated the economical efficiency similar to the Class plus Granite when it is backed by more than 20 years of durability.

• 한국가구학회지
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• 제28권3호
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• pp.224-232
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• 2017

Building energy saving have been put effort in a long time since buildings consume about 40.6% of total energy use, where heating, cooling and electrical lighting requirement results in energy consumption of building significantly. The window is an important part of building envelope, it usually brings a certain heat load from solar radiation while it allows light passing through, and properly leads to overheating in summer, hence the cooling load increase sand cause of thermal uncomfortable factor. The purpose of this study was to evaluate internal shade performance according to color and materials. There is growing interest in improving the sense of comfort among students who spend most of their time in the classroom. The study examined thermal environment and light environmental performance according to the color and materials of internal blinds to the school classroom. The results of this study were as follows; Among wooden blinds, aluminium blinds, and polyester blinds, the aluminium blinds were most excellent. In addition, among white blinds, light brown blinds, dark brown blinds, the light brown were most excellent.

• KIEAE Journal
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• 제16권4호
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• pp.63-69
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• 2016

Purpose: This preliminary study investigated a potential of the water wall systems that provide heat storage and natural lighting control simultaneously. Method: In order for transparency of the water wall to be controlled, the study first proposed two measures: to adjust transparency of the water wall; to control transparency of water wall surface. The performance of two measures then was verified and compared by experiments. In addition, a trade-off between heat collect and heat storage resulting from using additive for adjusting transparency was investigated. Result: The experiment showed that the two measures are similar in performance. The investigation of trade-off relation showed the additive should have the same heat storage as the water to prevent decrease in thermal performance of the water wall. As an economical measure to control transparency of the water wall, this study suggested a measure of secondary heat transfer systems using shading device that first absorbs solar radiation and then transfers heat to the water wall. The experiment show that performance of the proposed measure is similar to controlling transparency of water wall surface. In conclusion, it is expected that the performance of the water wall can be economically maximized by using the proposed mean in terms of heating, cooling and lighting energy saving.

• 대한가정학회지
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• 제18권1호
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• pp.67-82
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• 1980

The objectives of the study were to determine 1) energy uses for residential requirements, 2) if energy consumption and adoption of energy conservation attitudes and practices vary with independent variables family size, stage of family life cycle, homemaker's level of education, income, heating system, and number of electrical household items, and 3) if there is a correlation between energy conservation attitudes and practices. Questionnaires were given to the randomly selected homemakers I Seoul in the summer (September, 1979) and the winter (February, 1980). Analysis of variance and correlation were used to analyzed the data which consisted of 537 usable responses of 895 returned in the summer and 554 responses of 794 returned in the winter. The results are as follows: 1) The order of consumption rate of the direct energy uses for residential requirements was found to be heating and air conditioning, cooking, refrigeration, T.V., lighting, and miscellaneous. 2) Energy consumption and adoption of energy conservation attitudes and practices were significantly related to family size, homemaker's level of education, and the stage of family life cycle. (1) Families of five members revealed higher scores in attitudes and practices than families less than five or more than six. (2) The higher the homemaker's level of education, the more energy consumption and the higher scores I attitudes and practices were found. (3) Families in the middle stage of family life cycle tend to use more energy than younger or older families, but their scores in attitudes and practices were high. 3) There was a significant correlation between energy conservation attitudes and practices. However, the scores of the conservation practices were not as good as the attitudes. It may be attributed to either a lack of knowledge and/or financial difficulties, or a dissonance between the concept and implementation of energy conservation. 4) Recommendations for the energy-saving and energy-related public policies are: (1) to use such human resources as attitudes, values, feelings of agreement, and cooperation, as well as nonhuman resources for the energy conservation, (2) to develop a educational program and a creative system I order to implement energy conservation programs, and (3) to consider direct as well as indirect energy uses I selecting goods and services.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 D
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• pp.1956-1957
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• 2006

도로조명의 가로등은 에너지 절약을 위하여 격등제어 방식을 사용하고 있으나 등주 사이의 조도 분포가 균일하지 않아 조도가 낮은 곳에서 운전자가 불안감을 느끼고 피로가 급격히 증가하여 사고로 이어지는 등의 문제점에 대해서 각 가로등에 디밍제어 시스템을 구현하여 안정적인 조도를 유지하고 에너지 절감효과를 증가시킬 수 있는 방안을 제시하였다. 또한 가로등과 배전반 사이에 전력선통신 네트워크를 구성하여 시공과 관리에 소요되는 비용을 대폭 절감하고 신뢰성과 호환성이 높은 $L_{ON}W_{ORKS}$ 전력선통신방식을 사용하여 유지보수의 효율을 높일 수 있도록 구성하였다. 배전반과 관리자 사이에는 다양한 통신방식의 지원으로 관리자가 언제 어디서나 가로등 네트워크에 접근하여 관제가 가능할 수 있도록 가로등의 U-네트워크를 구축하여 에너지 절약형 가로등 디밍제어 시스템 을 제시하였다.

• 산업기술연구
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• 제30권B호
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• pp.113-118
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• 2010

In this paper, We proposed remote dimming control system for Light Emitting Diode(LED) street light using Power Line Communication(PLC). LED will be used widly by indoor or outdoor lighting because of semi-permanent life and environment restriction. For energy saving of street light, the dimming control system is very necessary and the PLC is a very efficient technique. Thus, in this paper we proposed the remote dimming control system for LED street light using PLC. A performance of the proposed system was validated by experimental results.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 전력전자학술대회 논문집
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• pp.466-469
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• 1998

The electronic fluorescent lamp ballast can promote the lighting efficiency up to 10-20% by driving high frequency with frequency transformation technique, and can completely eliminate the flickering phenomenon occurring from 60Hz frequency. The electronic ballast provides very high energy saving effects for it has high power fact than traditional ballast, and it is convenient to use. can extend the life of fluorescent lamp for it starts at once by driving with high frequency. However electronic ballast needs high price, and it can reduce the stability and reliability. This paper provides illumination systems which drive dozens of fluorescent lamps at the same time, to overcome these shortcomings of electronic ballast and utilize the advantage of electronic ballast.