• KIEAE Journal
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• v.17 no.1
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• pp.83-89
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• 2017

Purpose: Thermal sensation or thermal comfort was randomly used in many studies which focused on combined effects of thermal and acoustic environments on human perception. However, thermal sensation and thermal comfort are not synonyms. Thermal comfort is more complex human perception on thermal environment than thermal sensation. This study aims to investigate effects of noise on thermal sensation and thermal comfort separately, and also to investigate effects of temperature on acoustic sensation and comfort. Method: Combined thermal and acoustic configurations were simulated in an indoor environmental chamber. Twenty four participants were exposed to two types of noise (fan and babble) with two noise levels (45 dBA and 60 dBA) for an hour in each thermal condition of PMV-1.53, 0.03, 1.53, 1.83, respectively. Temperature sensation, temperature preference, thermal comfort, noisiness, loudness, annoyance, acoustic comfort, indoor environmental comfort were evaluated in each combined environmental condition. Result: Noise did not affected thermal sensation, but thermal comfort significantly. Temperature had an effect on acoustic comfort significantly, but no effect on noisiness and loudness in overall data analysis. More explicit interactions between thermal condition and noise perception showed only with the noise level of 60 dBA. Impacts of both thermal comfort and acoustic comfort on the indoor environmental comfort were analyzed. In adverse thermal environments, thermal comfort had more impact than acoustic comfort on indoor environmental comfort, and in neutral thermal environments, acoustic comfort had more important than thermal comfort.

• Journal of Environmental Health Sciences
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• v.43 no.3
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• pp.214-222
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• 2017

Objectives: A hospital is a complex building that serves many different purposes. The indoor environment in a hospital plays a major role in patient well-being and the work efficiency of the hospital staff. This study was conducted to evaluate overall comfort in two major hospitals over the course of one year. Methods: Various indoor environmental conditions were measured in two general hospitals for one year (April 2014 to April 2015). Monitoring alternated between the hospitals at one month per respective monitoring session. The indoor air temperature, relative humidity (RH), mean radiant temperature and air velocity were measured in order to calculate the predicted mean vote (PMV). Carbon dioxide concentration, noise level and illumination level were concurrently measured and applied to the overall IEQ acceptance model for the hospitals (IEQh). Results: The IEQh at the two general hospitals was different at five spaces within a building. The IEQh for summer and winter were significantly different. Real-time IEQh demonstrated that indoor comfort was affected by the hospital's operating hours due to operation of the HVAC system. The percentage of indoor comfort in the hospitals was higher using PMV than IEQh. Conclusion: IEQh in the hospitals was different at locations with different purposes. Indoor comfort assessment using IEQh was stricter than with PMV. Additional research is needed in order to optimize the IEQh model.

• Journal of the Korean housing association
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• v.17 no.5
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• pp.9-16
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• 2006

The researches on the environmental friendly buildings have carried out on the materials, environmental property, technical elements and etc., and various buildings with these green materials have built and under construction nowadays and became a new trend of the green building. And recently, new building technique which builds the wall with the soil and wood and very easy to construct (called M Earthen House) was introduced as the green building and rapidly propagated. But the research on the indoor climatic characteristics, the ability to control the environmental comfort and the influence to the human beings of these buildings are not sufficiently identified yet. In this paper, the indoor environmental characteristics and the temperature controlling ability of these buildings in summer season were measured and analysed by the Portable Indoor Air Quality Monitor(BABUC/A, LSI) measuring equipments, ana the subjective test on the thermal environment of the subjects were carried out to evaluate the thermal comfort. The results can be summarized as follows; 1) Compared to the outdoor dry bulb temp.($15.4{\sim}28.7^{\circ}C$), the indoor temp. was $19.5{\sim}26.8^{\circ}C$. It showed the temperature controlling ability of the M earthen house was outstanding. And the indoor relative humidity, compared to the outdoor($45.4{\sim}100%$), was $58.1{\sim}76.4%$, it showed the humidity controlling ability of the M earthen house was also outstanding. 2) The thermal environment was evaluated as 'comfort'(neutral-slightly warm) and the humidity was also evaluated as 'comfort'(neutral-slightly humid). So, the results of the physical and subjective evaluation on the indoor thermal comfort in summer season were 'neutral' and 'comfort' coincidently, it was confirmed that the controlling ability of the indoor temperature and humidity of the M earthen house was very excellent.

• Journal of the Korean housing association
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• v.8 no.2
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• pp.107-112
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• 1997

This thesis is dealt with the thermal environment, the indoor air environment, the sound environment and the light environment in P.C apartment house. The purpose of this study is to analyze degrees of 'the cognition'. 'the importance', and ‘the satisfaction' on indoor environmental factors and to evaluate comfort of indoor environment based on residents' responses. The questionnaire survey was given to the residents at P.C apartment complex in Rowon-Gu, Seoul. The following are the results obtained in this thesis. The results of Path analysis on comfort revealed that factors of direct effect to comfort were the satisfaction on indoor air environment and sound environment and the cognition on indoor air environment and sound environment. The satisfaction on indoor air environment was the biggest variable which decided the comfort. By the survey of P.C apartment residents' responses, the level of P.C apartment indoor comfort was found uncomfortable. It is meaningful to su99est the model evaluating comfort by residents' responses .

• Journal of Sensor Science and Technology
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• v.12 no.1
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• pp.24-33
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• 2003

This research is about a comfort sensing system for human environmental monitoring using a one-bodied humidity and temperature sensor and an air flow sensor. The thermal comfort that a human being feels in indoor environment has been known to be influenced mostly by six parameters, i.e. air temperature, radiation, air flow, humidity, activity level and clothing thermal resistance. Considering an environmental monitoring, we have designed and fabricated a one-bodied humidity and temperature sensor and an air flow sensor that detect air relative humidity, temperature and air flow in human environment using surface micromachining technologies. Micro-controller calculates a PMV (predicted mean vote) and CSV (comfort sensing vote) with sensing signals and display a PMV on LCD (liquid crystal display) for human comfort on indoor climate. Our work has demonstrated that a comfort sensing system can provide an effective means of measuring and monitoring the indoor comfort sensing index of a human being. Experimental results with simulated environment clearly suggest that our comfort sensing system can be used in many applications such as air conditioning system, feedback controlling in automobile, home and hospital etc..

• Journal of Environmental Health Sciences
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• v.41 no.6
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• pp.389-396
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• 2015

Objectives: A hospital is a complex building that serves many different purposes. It has a major impact on patient's well-being as well as on the work efficiency of the hospital staff. Thermal comfort is one of the major factors in indoor comfort. The purpose of this study was to determine thermal comfort in various locations in a hospital. Methods: Various indoor environmental conditions in a general hospital were measured in February 2014. The predicted mean vote (PMV) and carbon dioxide ($CO_2$) concentration were measured simultaneously in the lobby, office, restaurant, and ward. Results: The ward was the most thermally comfortable location (PMV=0.44) and the lobby was the most uncomfortable (PMV = -1.39). However, the $CO_2$ concentration was the highest in the ward (896 ppm) and the lowest in the lobby (572 ppm). The average PMV value was the most comfortable in the ward and the lowest in the lobby. In contrast, for concentration of carbon dioxide, the highest average was in the ward and the lowest in the lobby. Due to air conditioner operation, during operating hours the PMV showed values close to 0 compared to the non-operating time. Correlation between PMV and $CO_2$ differed by location. Conclusion: The PMV and concentration of carbon dioxide of the hospital lobby, office, restaurant and ward varied. The relationship between PMV and carbon dioxide differed by location. Consideration of how to apply PMV and carbon dioxide is needed when evaluating indoor comfort.

• International Journal of Air-Conditioning and Refrigeration
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• v.9 no.3
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• pp.36-45
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• 2001

During the last decade, an increasing interest in Underfloor Air-Conditioning (UFAC) systems has emerged. The purpose of this paper is to evaluate the indoor environmental performance of office buildings with UFAC system in order to develope the design prototype of this system. The physical measurements and the Interviewing survey of occupant's sensation responses to the environment were carried out. Measurements and survey were made of the thermal environmental factors such as air temperature, relative humidity, air velocity, globe temperature, and the other several environmental factors such as the sound level and the illuminance of working plane, etc. And, the air quality was evaluated by measuring the concentration of suspended particles, carbon monoxide, and carbon dioxide in the room. Furthermore, the paper appraises the various indoor environmental factors of the room by using post-occupancy evaluation (POE) method in office building with UFAC system, and thus, it suggests the basic data for assessing the indoor comfort based on field measurements and survey .

• Advances in Computational Design
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• v.7 no.4
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• pp.321-343
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• 2022

Museum buildings display artefacts for public education and enjoyment, ensuring their long-term safety and the comfort of visitors by following strict indoor environment control protocols using mechanical Heating, Ventilation and Air Conditioning (HVAC) systems to keep the (environmental) variables at a fixed comfort level. Maintaining this requires constant supply of energy currently mostly sourced from the combustion of fossil fuels which exacerbates climate change. However, a review on the effects of the indoor environmental variables on museum artefacts as well as museum visitors revealed that there is no specific point at which artefact deterioration occurs, and that there are wide ranges of conditions that guarantee the long-term safety of artefacts and human comfort. Visits to museum buildings in hot-humid tropical climate of Nigeria revealed that strict indoor environmental practices were adopted. Even when appropriate micro-climatic conditions are provided for artefacts, mechanical HVAC systems remain necessary for visitor comfort because almost no consideration is given to natural ventilation. With the current global push towards energy management, this paper reviewed passive environmental control practices, architectural design strategies, and discusses the adaptation of double skin façade with jali screens, and the notion of smart materials, which can satisfy the range of requirements for the long-term safety of artefacts and levels of human comfort in buildings in hot-humid tropical climate, without mechanical HVAC systems. This review would inspire more discussions on passive, energy efficient, smart and climate responsible popular architecture, challenging current thinking on the impact of the more accepted representative architecture.

• Journal of Korean Society for Atmospheric Environment
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• v.31 no.4
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• pp.385-395
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• 2015

This study evaluated indoor environmental characteristics in an office room equipped both with ventilation window system and central cooling system. Fresh air is supplied only by the central cooling system whereas indoor air is discharged outside through both ceiling diffuser and a ventilation window system. Numerical study is conducted by changing the volumetric flow rates of exhaust ports of each system. For estimating the performance of this coupled system, $CO_2$ concentration and Predicted Mean Vote (PMV) were calculated using Computational Fluid Dynamics (CFD) simulation. The more the ceiling diffuser exhausts indoor air, the more the $CO_2$ concentration decreases. However, when the ventilation window system exhausts more indoor air, thermal comfort level gets improved in the office room with cooling system. Therefore, when the ventilation window system is operated, the coupled operation with central cooling system should be considered for enhancing indoor air quality and thermal comfort, together.

• Journal of IKEEE
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• v.19 no.4
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• pp.603-609
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• 2015

Thermal comfort is one of the fundamental aspects of indoor environmental quality and it is strongly related to occupant satisfaction and energy used in building. In this paper, we proposes smart comfort algorithm that save energy and provide a pleasant and comfortable environment for workers by the indoor comfort conditions(Predictive Mean Vote) detection and controlling the temperature and humidity, air flow. Simulation results, heating and cooling control of the thermal comfort control can be compared with the existing general air conditioners reduces the power of 0.5kW and indoor comfort can be maintained. Also, It showed a 49.2% improvement in the light by lighting control algorithm.