• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.5
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• pp.108-114
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• 1999

The thermal environmental chamber has been using in maintaining weather condition keeping thermal capacity under heating and cooling load fluctuation and for the performance testing of cooling system or air-conditioner on artificial envi-ronment. In ordder to make the various environmental conditions in the thermal environmental chamber the proper cooling system is necessary to eliminate the heating load produced inside the chamber and to maintain the designed environmental condition. For this reason the optimal design of cooling system and the prediction of performance is also required. This paper describes the prediction of performance of cooling system in the thermal environmental chamber with the capacity of 37,000kcal/hr which is developed for the test of performance in heating mode of heat pump system, In the results this paper is trying to develop simulation program on the base of mathematical models and which can be applied effectively to the optimal design of cooling system and prediction of performance to the inside and outside change of envi-ronmetal load.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.E
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• pp.41-58
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• 1998

In this study, a wide range of volatile organic constituents of environmental tobacco smoke (ETS) were determined using an environmental chamber, where ETS is the sole source of target compounds. ETS was generated in an environmental chamber by a number of different cigarettes, including the Kentucky reference cigarette and eight different commercial brands. More than 30 compounds were measured simultaneously for a total of twelve experimental runs. The target compounds are classified into three major classes, i.e. vapor phase ETS markers including 3-ethnylpyridine (3-EP) and nicotine, carbonyl compounds including formaldehyde, and volatile organic compounds (VOCs). The results from the chamber study were used to generate characterized ratios of selected VOCs to 3-EP, a vapor phase ETS marker. Emission factors for VOCs associated with ETS were also estimated. The characteristic ratios appeared to be generally in good agreement with published data obtained by environmental chamber studies similar to this study. This implies that the ratios may be useful for identifying and quantifying the impact of ETS as a source of target compounds in 'real world' indoor environments, which is affected by a complex mixture of multi-sources. The environmental chamber method described here provides a direct and reliable method to compare the ETS generated by different cigarettes. The method can also be applied to the simultaneous determination of many different ETS components.

• Journal of Environmental Science International
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• v.18 no.10
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• pp.1123-1134
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• 2009

This study was designed to evaluate qualitatively and quantitatively the pollutant compositions, which were emitted from three types of mosquito repellents(MRs)(mat-, liquid-vaporized, and coil-type) by utilizing a 50-L environmental chamber. A qualitative analysis revealed that 42 compounds were detected on the gas chromatography/mass spectrometer system, and that the detection frequency depended upon chemical types. Nine of the 42 compounds exhibited a detection frequency of 100%. Four aromatic compounds(benzene, ethyl benzene, toluene, and xylene) were detected in all test MRs. The concentration equilibriums in the environmental chamber were achieved within 180 min after sample introduction. The coil-type MR represented higher chamber concentrations as compared with the mat- or liquid-vaporized-type MR, with respect to the target compounds except for naphthalene. In particular, the chamber concentrations of ethyl benzene, associated with the use of coil-type MR, were between 0.9 and $65\;mg\;m^{-3}$ whereas those of mat- and liquid-vaporized-type MRs we~e between 0.5 and $2.0\;mg\;m^{-3}$and 0.3 and $1.4\;mg\;m^{-3}$, respectively. However, naphthalene concentrations in the chamber, where a liquid-vaporized-type MR was placed, were measured as between 17.8 and $56.3\;mg\;m^{-3}$, but not detected in the chamber, where a mat- or coil-type MR was placed. The empirical model fitted well with the time-series concentrations in the environmental chamber(in most cases, determination coefficient, $R^2$ ≿ 0.9), thereby suggesting that the model was suitable for testing emissions. In regards to the target compounds except for benzene, although they were emitted from the MRs, health risk from individual exposure to them were estimated not to be significant when comparing exposure levels with no observed adverse exposure levels or lowest observed adverse exposure levels of corresponding compounds. However, it was concluded that the use of MRs could be an important indoor source as regards benzene.

• Journal of Environmental Health Sciences
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• v.43 no.1
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• pp.87-94
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• 2017

Objectives: This study was conducted to determine the impact of aquariums on indoor air quality for improving humidity and reducing indoor air pollutants. Methods: An air-conditioning chamber was used to determine humidity increase by aquarium volume at three different temperatures ($20^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$). Humidity increase was measured for 21 hours ($20^{\circ}C$) and 12 hours ($25^{\circ}C$, $30^{\circ}C$) while placing five different volume of aquarium in the chamber. Concentrations of several volatile organic compounds and formaldehyde were measured after a known amount was injected into the chamber with and without an aquarium. Results: The humidity inside the chamber increased when the aquarium was inside the chamber. Humidity change was similar at $20^{\circ}C$, $25^{\circ}C$, and $30^{\circ}C$, but slightly higher at higher temperatures. The bigger the aquarium volume, the higher was the humidity increase that occurred. Humidity increase by the aquarium was sufficient to increase indoor humidity in winter and negligible in summer. Concentrations of some water-soluble indoor air pollutants and formaldehyde were decreased with the aquarium inside the chamber. Conclusions: An aquarium could increase indoor humidity in winter, while the humidity increase is negligible in summer. An aquarium could decrease some water-soluble indoor air pollutants, including formaldehyde. This result implies that an aquarium may have positive effects on indoor environmental quality.

• Journal of Environmental Health Sciences
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• v.44 no.4
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• pp.360-369
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• 2018

Objectives: Outdoor tobacco smoke can penetrate into the indoor environment through cracks in the building envelope. This study aimed to characterize the particle size distribution of infiltrated secondhand smoke (SHS) through the gap in a single glazed and a secondary glazed window according to pressure differences in a chamber. Methods: Two polyvinyl chloride sliding windows were evaluated for infiltration, one with a glazed window and the other with a secondary glazed window. Each window was mounted and sealed in a polycarbonate chamber. The air in the chamber was discharged to the outside to establish pressure differences in the chamber (${\Delta}P$). Outdoor smoking sources were simulated at a one-meter distance from the window side of the chamber. The particle size distribution of the infiltrated SHS was measured in the chamber using a portable aerosol spectrometer. The particle size distribution of SHS inside the chamber was normalized by the outdoor peak for fine particles. Results: The particle size distribution of SHS inside the chamber was similar regardless of window type and ${\Delta}P$. It peaked at $0.2-0.3{\mu}m$. Increases in particulate matter (PM) concentrations from SHS infiltration were higher with the glazed window than with the secondary glazed window. PM concentrations of less than $1{\mu}m$ increased as ${\Delta}P$ was increased inside the chamber. Conclusions: The majority of infiltrated SHS particles through window gap was $0.2-0.3{\mu}m$ in size. Outdoor SHS particles infiltrated more with a glazed window than with a secondary glazed window. Particle sizes of less than $1{\mu}m$ were associated with ${\Delta}P$. These findings can be a reference for further research on the measurement of infiltrated SHS in buildings.

• Journal of Environmental Science International
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• v.32 no.2
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• pp.131-137
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• 2023

Filter and microbalance sensitivity in measuring fine particulate matter mass is greatly influenced by particulate properties and environmental factors. Temperature and humidity control inside a measuring chamber with a microbalance, and neutralization of static charges on filters are essential for consistent filter weighing. Commercial weighing chambers are expensive with a unit price of tens of millions won. This study developed an inexpensive weighing chamber for weighing fine particulate matter and evaluatedits weighing performance. A microbalance with 1 ㎍ precision was used to measure the weight of a filter. The microbalance was set in a transparent acrylic enclosure (100 × 60 × 65 cm³) equipped with temperature and humidity control equipments. Weighing performance of the chamber was examined using Teflon filters with or without different particulate sample types. Temperature and humidity were maintained at approximately 23.2±1.2 ℃ and 36.2±1.8℃ for 8 days, respectively.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.5
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• pp.534-544
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• 2011

The secondary aerosol forming potential of ambient air was first measured with the Potential Aerosol Mass(PAM) chamber at Gosan supersite on Jeju island from October 22 to November 5, 2010. PAM chamber is a small flowthrough photo-oxidation chamber with extremely high OH and $O_3$ levels. The OH exposure in the PAM chamber was $(2{\pm}0.4){\times}10^{11}{\sim}(6{\pm}1.2){\times}10^{11}$ molecules $cm^{-3}$ s and was similar to 2 to 5 days of aging in the atmosphere. By periodically turning on and off UV lamps in the PAM chamber, ambient aerosol and newly formed aerosol (e.g. called as PAM aerosol) was alternately measured. Aerosol number and mass concentration in the range of 10~487 nm in diameter was measured by SMPS 3034. With UV lamps on, the nucleation mode particles smaller than 50 nm in diameters were formed. Their number concentration was greater than 105 $cm^{-3}$, leading to increase in aerosol mass by 0~8 ${\mu}gm^{-3}$. The variations of PAM and ambient aerosols were greatly dependent on characteristics of air masses such as precursor concentrations and degree of aging. This preliminary results suggests that PAM chamber is useful to assess the aerosol formation potential of air mass and its impact on the air quality. The further analysis of data with gaseous and particulate measurements will be done.

• Journal of Biosystems Engineering
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• v.32 no.3
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• pp.166-172
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• 2007

Egg quality indices are related with freshness, size of air chamber, loss of weight, and viscosity of the yolk and the protein. However, since the described quality parameters require measured in a destructive way, it is not suitable to inspect the egg quality with complete enumeration. Therefore, this study was performed to investigate the potential of image analysis method for evaluation of internal egg quality. Samples of 90 fresh eggs were collected immediately after laying and stored up to 24 days. Five eggs were randomly drawn from each storage condition (packing vs unpacking) at a regular interval and loss of weight, specific gravity and size of air chamber were measured. The image analysis for nondestructive measurement of size of air chamber was also studied. Results showed that the egg weight and gravity gradually decreased with increasing of storage days, while the size of air chamber linear increased caused by evaporation of water through the shell. A relationship a between conventional method and the image analysis method for measuring the size of air chamber was developed with the correlation coefficient of 0.928. The new finding implied that image analysis might provide a useful nondestructive tool to assess internal egg quality.

• Proceedings of the Korean Fiber Society Conference
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• 1998.04a
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• pp.285-290
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• 1998

The purpose of this study is the design of the climate chamber. Experiments was performed in a climate chamber that was running Under Floor Air-Conditioning System(UFAC). The chamber has a diffuser in the middle of the floor, and exhausts on the ceiling, simulating underfloor air conditioning system.

• Journal of Environmental Science International
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• v.25 no.8
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• pp.1191-1206
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• 2016

Transported deposit was accumulated in a grit chamber built at the mouth of Yeocheoncheon in 1987 with the intention of blocking the influx of sediment into the Ulsan-harbor. This study attempted to analyze the effects of the transported deposit on the water quality at Yeocheoncheon. Only one episode of dredging has been performed in the approximately 25 years since the grit chamber were built, leading to the formation of stagnant water in the grit chamber due to a large amount of transported deposit. The deposit has a relatively high organic content, in the range of 11.7-25.9% (mean 18.3%). It appears that the main reason for the upstream transport of water pollution from the mouth of the Yeocheoncheon is the tides. The effects of organic content and stagnant water on water quality were analyzed using WASP. Moreover, the changes in water quality arising due to the removal of the grit chamber were analyzed. Results indicated that BOD improved by 18.8-100%, while T-P improved by 90.0-617.4%, between the grit chamber and Hanbi-Gyo, which is located 1.3 km away from the grit chamber.