• 한국멀티미디어학회논문지
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• 제23권2호
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• pp.155-165
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• 2020

In this paper, we propose a smart thermostat temperature set-point control method based on machine learning and rule engine, which controls thermostat's temperature set-point so that it can achieve energy savings as much as possible without sacrifice of occupants' comfort while users' preference usage pattern is respected. First, the proposed method periodically mines data about how user likes for heating (winter)/cooling (summer) his or her home by learning his or her usage pattern of setting temperature set-point of the thermostat during the past several weeks. Then, from this learning, the proposed method establishes a weekly schedule about temperature setting. Next, by referring to thermal comfort chart by ASHRAE, it makes rules about how to adjust temperature set-points as much as low (winter) or high (summer) while the newly adjusted temperature set-point satisfies thermal comfort zone for predicted humidity. In order to make rules work on time or events, we adopt rule engine so that it can achieve energy savings properly without sacrifice of occupants' comfort. Through experiments, it is shown that the proposed smart thermostat temperature set-point control method can achieve better energy savings while keeping human comfort compared to other conventional thermostat.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 춘계학술발표대회 논문집
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• pp.115-120
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• 2009

The studies for mechanical performance development have been examined to reduce energy consumption in building construction field. However, The energy consumption using in building for heating is impacted by not only system performance but also PMV particularly at temperature and clo. Most energy using in building part is mainly consumed for heating and cooling to keep comfort temperature. Heating energy consumption is bigger than cooling energy in Korea because of temperature difference in winter in comparison with summer at apartment building. This means that energy consumption can be changed by occupancy's comfort setting temperature in apartment building. This study evaluate actual comfort temperature range by clo and examined heating energy consumption by Esp-r and CO2 reduction possibility. The results show that keeping ASHRAE standards can reduce heating energy up to 23%; also, wearing underclothes with ASHRAE standard can reduce heating energy up to 47.8%. Option 4 showing Maximum CO2 emission reduction indicates that kerosene. LNG and electricity can reduce 1.5t, 1.7t, 2.46t respectively in comparison with option 2.

• 한국태양에너지학회 논문집
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• 제30권4호
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• pp.49-54
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• 2010

Most energy using in building part is mainly consumed for heating and cooling to meet occupancy's comfort temperature. Generally, heating energy consumption show high value than cooling energy in Korea because of high temperature difference in winter season as compared with summer in apartment building. The efforts to develope mechanical performance have been studied to reduce energy consumption in building energy field until now. However, the energy consumption in building is impacted by not only system performance but also PMV particularly at temperature and Clo value. This means that energy consumption can be changed by occupancy's comfort setting temperature in apartment building. This study investigated the passibility of overheating in apartment building by occupant' slow Clo and its setting temperature from preceding research and then the heating energy consumption by setting temperature was calculated with ESP-r. The effects of heating energy and $CO_2$ reduction are also evaluated quantitatively with Clo value. The results showed that keeping ISO-7730 standards can reduce heating energy up to 21% in compared with option 2; also, wearing underclothes with ISO-7730 standard can considerably reduce heating energy consumption up to 50%. As compared with option 2, the reduction of $CO_2$ emission for option 3 showed 0.63TCO2 of kerosene, 0.49TCO2 of LNG and 1.09TCO2 of electricity. The option 4 can be reduced by 1.48TCO2 of kerosene, 1.16TCO2 of LNG and 2.57TCO2 of electricity respectively.

• KIEAE Journal
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• 제14권1호
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• pp.23-30
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• 2014

The preferred illumination environment in accordance with the actions taken by the occupants of the rooms in residences differs significantly between different cultures and circumstances in and out of the country. In this regard, the purpose of this study is to evaluate the visual performance of various illumination environments in residential spaces by allowing the participants of the experiments to select the kind of illumination environment they prefer as the occupants of the room. For this purpose, we prepared a mock-up residential space of $6.2m{\times}4.5m{\times}2.5m$, where the experiments for this study were conducted. Then, three illuminance settings (30lx, 100lx, and 150lx) and three color temperature settings (2700k, 4000k, and 6500k) were selected as the properties of the physical environment where the tests were to be conducted. The survey was conducted with 30 study subjects, with whom the level of visual comfort and the lighting adjustment evaluation by different activities were carried out. The level of visual comfort in lighting in a residential context turned to be more influenced by the color temperature and illuminance compared to other factors. Except for the test item, 'comfort,' all test items showed positive reactions when the illuminance was 150lx, which was rather light. In 'comfort,' the test subjects appeared to prefer warm color temperature of 2700k. As we allowed the occupants to adjust the lighting environment in accordance with the conditions of the subjects and the activities they performed, the subjects regarded 150lx - 4000k setting as comfortable, while they preferred 150lx-5400k configuration for working. In case of resting, the subject answered that the configuration of 30lx -2700k setting to be visually comfortable.

• 수산해양교육연구
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• 제23권2호
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• pp.153-161
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• 2011

Creating standards on thermal environment has been organized traditionally based on the youth and the manhood who are in mainly active layer of a society. However, traditional creating standards have differences from the physiology of the aged who have weak physical ability than younger person. As a result, it causes a health problem of the aged. Therefore, In this study, we had a basic study to create a comfortable thermal environment which had considered to a physical ability and a physiology of the aged, and build a ecological residence space to maintain health. We had several experiments with the aged; Experiment, Comfort Sensation Vote, Mean Skin Temperature and Analyzing HRV. The result have following by: 1)For the aged, the summer recommend temperature, $26^{\circ}C$, is appropriate within first 30 ~ 40 minutes, but it should be increasing the temperature after that time. 2) By considering PMV status and thermal feeling of the aged, they are prefer to higher temperature than normal setting of air-condition system. 3) In the condition of the summer recommend temperature, $26^{\circ}C$, they had answered in neutral or comfort with the comfort sensation vote. However, we had figure out that they had stress in a lower temperature by analyzing the result of HRV.

• 설비공학논문집
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• 제22권7호
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• pp.460-467
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• 2010

In housing units constructed recently in Korea, the length of ondol coil is different in each room, so the flow rate of hot water is adjusted by setting valve opening. If the flow rate is not appropriate for heating load, the room temperature seriously deviates from the set temperature range for comfort. In particular, too small valve opening can induce a noise by cavitation. In order to adjust the valve opening, two methods by zone area and a new method by return temperature rise were modelled and simulated using TRNSYS and EES. As a result, heating energy consumption during one week was the same on three methods, but the room temperature of the new method minimally deviated from the range of set temperature with a low possibility of noise.

• 한국지역사회생활과학회지
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• 제24권4호
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• pp.583-589
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• 2013

This study was to provide the information for optimum utilization of the air-conditioning system in the human health and energy saving perspective. Subjects were 17 male and female college students(7 males and 10 females) with normal weight. They wore a short sleeved shirt, knee length trousers, socks, and underwear(0.4clo). They were asked to choose the preferred temperature from different environmental temperatures($28^{\circ}C$, $25^{\circ}C$). The physiological responses were measured and the subjective sensation was voted during the step changes of environmental temperature, starting at $28^{\circ}C$ to $25^{\circ}C$ with $1^{\circ}C$ decrease every 20 minutes. The preferred temperature was $25.9{\pm}0.4^{\circ}C$ for males and $26.9{\pm}0.2^{\circ}C$ for females at $28^{\circ}C$ and $24.8{\pm}0.6^{\circ}C$ for males and $25.6{\pm}0.1^{\circ}C$ for females at $25^{\circ}C$. The preferred temperature decreased about $1.3^{\circ}C$ while the environmental temperature changed $3^{\circ}C$. During the environmental step changes, mean skin temperature decreased more in females while the oxygen uptake and rectal temperature were kept constant for both males and females. We found the preferred temperature was affected by the exposed temperature and the thermal sensation in the condition. Subjects preferred a lower environmental temperature when they were exposed to a lower temperature with cooler sensation. Therefore, in the perspective of human health and energy saving, it is recommended to start setting the air-conditioning temperature higher than the preferred temperature.

• 전기학회논문지
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• 제62권2호
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• pp.164-170
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• 2013

The commercial buildings are consuming about 30% of total energy used in Korea. And a large amount of energy consumption in commercial buildings is consumed by HVAC(Heating, Ventilation, Air Conditioning) system. Therefore, if we can reduce the energy consumption in HVAC or air-conditioning system in commercial buildings, the overall energy consumption in Korea can be reduced. Currently, an electricity charge called Time of Use (TOU) is applied to typical commercial buildings. This paper proposes the novel energy management method where the temperature setting of air-conditioning system are adjusted to minimize the use of electrical energy while indoor comfort level is retained. The simulation test for a typical commercial building shows that the proposed method gives over 10% savings in electricity bills and electricity consumption compared to the conventional air-conditioning method.

• 한국조경학회지
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• 제41권1호
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• pp.21-33
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• 2013

이 연구는 대구광역시에 위치한 중심상업지역을 포함한 국채보상운동공원과 2.28공원지역을 대상지로 미기후 실측과 컴퓨터 시뮬레이션을 이용해 여름철 인간 열환경 지수를 분석하고, 그 지수를 토대로 인간 생기후지도를 제작하여 향후 도시 조경계획 및 디자인에 이용할 방안을 모색하는데 목적을 두었다. 인간 열환경 지수를 분석하기 위해 필요한 자료들로서 기후자료(기온, 습도, 풍속, 태양 및 지구 복사에너지)와 도시공간 구성자료(건물의 위치와 높이; 수목의 위치와 높이; 수목의 종류와 건물 벽, 지표면의 재질; 태양 복사에너지 반사율과 지구 복사에너지 방사율)를 지리정보시스템 자료와 실측을 통해 구축하였다. 그 결과, 풍속이 약할수록 도시중심상업지역이 공원보다 높은 기온을 나타냈으며, 습도는 반대의 현상을 보였다. 특히, 주풍 방향의 길들은 지역풍의 영향으로 주풍과 직각방향의 길들보다 더 낮은 기온을 나타냈다. 여름철 열환경 지수에서 가장 큰 영향을 미치는 기후요소는 태양직사광선으로 나타났으며, 도시공간에서 그늘 조성이 가장 효과적인 열환경 개선 방법이었다. 그 방법 중 파고라에 수목그늘을 이중적으로 조성하는 방법이 가장 효과적이었으며, 북향의 건물 벽 앞에 수목그늘을 조성하는 것이 그 다음으로 효과적이었다. 또한, 수종 선택뿐만 아니라 식재방식에도 중점을 두어야 하는 것으로 나타났다. 양지의 열환경 지수는 따뜻한 정도(warm)에서 매우 더운 정도(very hot)로 나와, 음지의 중간(neutral)에서 따뜻한 정도(warm)에 비해 불쾌한 열환경이 조성되었다. 특히, 양지는 넓은 광장형태의 지역들이 좁은 길보다 더 불쾌한 결과를 보였다. 재질의 반사율을 건물 벽 0.15, 지표면 0.1 낮췄을 때, 열환경 지수가 음지에서는 한 단계 중 1/6만큼, 양지에서는 1/3만큼 감소됨을 알 수 있었다. 이와 같은 미기후적 접근방식이 도시 열환경 개선방안을 찾는데 효과적일 것이다.

• Architectural research
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• 제17권3호
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• pp.109-115
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• 2015

The dynamic pricing of electricity, where the electricity rate increases in a time zone with a high demand for electricity is typically applied to a building whose power reception capacity is greater than a certain size. This includes the time of use(TOU) electricity pricing in Korea which can induce the effect of reducing the power demand of a building. Meanwhile, a VRF (Variable Refrigerant Flow) system that uses electricity is regarded as one of the typical heating and cooling systems along with central air conditioning (central HVAC) for its easy operation and application to the building. Thus, to reduce power energy and operating costs of a building in which the TOU and VRF systems are applied simultaneously, we suggested a control for changing the indoor temperature setting within the thermal comfort range or limiting the rotational speed of an inverter compressor. In this study, to describe the features of the above-mentioned control and verify its effects, we evaluated the results obtained from the analysis of its operation data. Through the actual measurements in winter operations for 73 days since mid- December 2014, we confirmed a reduction of 10.9% in power energy consumption and 12.2% in operating costs by the new control. Also, a reduction of 13.3% in power energy consumption was identified through a regression analysis.