• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.5
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• pp.304-313
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• 2010

During recent years, various studies have demonstrated that indoor chemical pollution causes health problem and also negatively affect the performance of work by occupants. Building materials have been concerned as indoor chemical sources. Some of guidelines and certification system has been developed and resulted as dramatic decrease of harmful indoor chemicals such as formaldehyde and volatile organic compounds. Also, Home furniture and electrical devices has been concerned as one the primary influence the indoor chemical concentration in residential spaces. It is found that various kinds of electric home appliances have a significant source of chemical emission in indoor environments. In this study, the methodologies of detecting harmful chemicals from various kinds of products has been developed with large chamber measurement system and suggest some of the evaluation method for the chemicals from the home appliances as TV sets.

• Journal of the Korean Solar Energy Society
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• v.27 no.4
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• pp.59-65
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• 2007

This study is to propose the basic data for deciding remodeling of wornout educational facilities. In order of it, the indoor environmental standard, the actual conditions of thermal environment and sound insulation of walls were examined through field measurement in the subjected open elementary school(J school) and modernization model of elementary school(Y school) which they are located in Seoul. As the result, standard for indoor environmental factors of educational facilities which is established by Ministry of Education is not subdivided into indoor environmental performances considering usages and characteristics of classrooms for comfortable indoor environment. The vertical temperature difference in general classroom and in open classroom showed to be $11.2^{\circ}C$ and $12.1^{\circ}C$ respectively, while indoor temperature of special classroon was, on the whole, higher than that of any other classroom due to its specific heat flux of wall materials. The sound insulation performance of the masonry brick wall of classroom satisfied the minimum standard of AIJ, Architectural Institute of Japan, in the open elementary school and the modernization model of elementary school. That is to say, the movable partition wall between the classroom and the corridor disturbed students in their class in the open school.

• Journal of Environmental Science International
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• v.15 no.10
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• pp.929-933
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• 2006

Indoor air quality is the dominant contributor to total personal exposure because most people spend a majority of their time Indoors. Especially when indoor environments have sources of contaminants, exposure to in-door air can potentially pose a greater threat than exposure to ambient air. In this study, estimations of volatile organic compounds and formaldehyde omission rate in indoor environments of new apartments were carried out using mass balance model in indoor environment, because indoor air quality can be affected by source generation, outdoor air level, ventilation, decay by reaction, temperature, humidity, mixing condition and so on. Considering the estimated emission rate of volatile organic compounds and formaldehyde, it Is suggested that new apartment should be designed and constructed in the aspect of using construction materials to emit low hazardous air pollutants.

• International Journal of Internet, Broadcasting and Communication
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• v.11 no.1
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• pp.27-38
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• 2019

Sensors collect information for Internet of Things (IoT)-based services. However, indoor construction sites have a poor communication environment and many interfering elements that make it difficult to collect sensor information. In this study, a network was constructed between a Bluetooth Low Energy (BLE)-based IoT device based on a serverless IoT framework and a router. This experimental environment was applied to large- and small-scale indoor construction sites. Experiments were performed to test the communication performance of BLE-based IoT devices and routers at indoor construction sites. An analysis of the received signal strength indication (RSSI) graph patterns collected from the communication between the BLE-based IoT devices and routers for different testbed site situation revealed areas with good communication performance and poor communication performance due to interfering factors. The results confirmed that structural components of the building as well as the materials, equipment, and temporary facilities used in indoor construction interfere with the communication performance. Construction project managers will require improved technical knowledge of IoT, such as optimizing the router placement and matching communication between the router and workers, to improve the communication performance for large-scale indoor construction.

• Journal of the Korean Wood Science and Technology
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• v.46 no.6
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• pp.735-747
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• 2018

Radon radiation exposures in home have been posed as a potential cancer hazard. This research aims to present the basic data of the indoor radon concentration level by examining the radon exhalation rates of wood species. Radon exhalation rates from five commonly used wood species in Korean wood building construction were measured with Continuous Radon Monitor (CRM), Model 1028 (Sun Nuclear Co., USA) using the Closed Chamber Method (CCM). The mass exhalation rate was observed to vary from $0.00089Bq{\cdot}kg^{-1}{\cdot}h^{-1}$ to $0.00181Bq{\cdot}kg^{-1}{\cdot}h^{-1}$, whereas the surface exhalation rate was observed to be $0.00677-0.01517Bq{\cdot}m^{-2}{\cdot}h^{-1}$. The radon exhalation rate of Quercus accutissima Carruth (white oak) which has the highest density showed the highest figure among the five wood species, on the other hand, the rest of four species showed similar results which were similar to the radon exhalation rates of wood in the U.S.A. and Canada. The average of the concentration measured by the CCM represented well up to the second half-life period (7.7 days). Because result of these small quantities seems to indicate that radon exhalation from the tested wood species has almost negligible impact, the main culprit of the high indoor radon concentration is clearly derived from the background of surrounding wood house. Therefore, as a safety precaution, infrastructures made of wood materials should be designed with the consideration of influx of radon and built accordingly. Furthermore, it is highly desirable that wood will be needed to use for furniture and interior finishing material in indoor environment.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.2 s.115
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• pp.35-42
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• 2006

This study was carried out to develop a new application field of traditional Hanji and obtain the basic data for producing functional Hanji using sawdust ceramics and rice-husk ceramics as an architectural material. The results measuring water vapor permeance and water vapor absorption for using window materials and wallpapers are as follows. Hanji wallpaper has good things in controlling indoor space comfortably. Particularly, ability of controlling humidity of Hanji wallpaper affects indoor space comfort and human health. In the case indoor humidity is higher than outdoor humidity, according to the addition of ceramics, Hanji wallpapers maintain the humidity by retaining water vapor molecules in the pores of ceramics. Thus the Hanji wallpapers with ceramics, in particular rice-husk ceramics, make it superior to non-ceramics Hanji wallpapers in maintaining the humidity indoors.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.981-985
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• 2008

Construction company's role is getting bigger recently because of interest of indoor air quality problem. The using environment-friendly building finishing material is the most benefit method to reduce pollutants in house. It is confirmed the actual condition of environment-friendly building finishing material such as wallpapers, wooden flooring boards, glues, paints, adhesives, plaster boards that are used the work of apartment construction in 2006-2007. It shows that environment-friendly materials have excellent grade mostly, general materials have pass I, pass II grade mostly and are high TVOC emission.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.7
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• pp.563-570
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• 2006

We investigated the emission characteristics of gaseous organic contaminants from building materials and newly constructed apartments. The emission test for building materials was done with small chamber method, and field measurements in newly constructed apartment were carried out by Korea Standard Test Method for Indoor Air Quality. First, the emission test by small chamber showed that the TVOC emission from building materials was much higher than formaldehyde. On the other hand, as expected, considerably high concentration of both TVOC and HCHO was detected in the new apartment.

• Journal of the Korean Wood Science and Technology
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• v.34 no.2
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• pp.22-29
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• 2006

On purpose to reduce accumulated moisture and to prevent moisture condensation in a light-frame wall, thermal characteristics and moisture behaviors were investigated for four different wall assemblies; a) typical wall, b) addition of vapor retarder between the insulation and the gypsum board, c) addition of air gap for natural ventilation behind the siding, d) composition with b) and c). Each wall was tested under two climate conditions; 1) $20^{\circ}C$, 50% RH (indoor) and $30^{\circ}C$, 85% RH (outdoor), 2) $30^{\circ}C$, 85% RH (indoor) and $20^{\circ}C$, 50% RH (outdoor).The results showed that the typical wall assembly had poor resistance against moisture intrusion from the inside of building. Outdoor and indoor humidity caused the moisture condensations on the inside of the siding and the back surface of the sheathing respectively. The addition of a vapor retarder did not give significant improvement in preventing the moisture intrusion.

• Journal of the Korean housing association
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• v.26 no.4
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• pp.23-32
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• 2015

The purpose of this research is to analyze characteristics and related factors of IAQ (Indoor Air Quality) in newly built wooden houses by measuring pre and post occupancy. The subjects were five wooden houses which were built with similar materials and completed from July to December 2013. Measuring factors were TVOC, HCHO, PM10, $CO_2$, CO, indoor temperature, and relative humidity. As the result of pre occupancy measuring, the houses that revealed the lowest TVOC concentration or HCHO concentration were satisfied with "the standard for newly built apartment houses". Therefore, IAQ by the wooden structures is considered to be in good condition. However, in cases of partial value exceeded the standard, the reason is analyzed to be the materials of molding, wrapping doors, built-in closet, or kitchen furniture, etc. rather than structure materials. Most PM10 concentration level showed slightly below "the standard for occupied multi-use facilities". Remaining of construction dust was considered to be the reason. As the result of post occupancy measuring, every value except of one subject's TVOC concentration was lower than pre occupancy, explaining the importance of natural ventilation.