• Journal of Advanced Marine Engineering and Technology
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• v.32 no.5
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• pp.717-723
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• 2008

The purpose of this study is to measure and analyze the indoor thermal conditions of a 8,500GT class chemical carrier which was launched on July 2007. The measurement was operated from 4th June to 4th June 2007, just before handing over to Owner. Followings are the results of this study. (1)The temperature variations of supply air were related to the outdoor temperature variations, but the humidity was stable at $65{\sim}80%$. (2)The temperature variations at the representative position of bridge, restaurant, crew's cabin showed gentle slopes. but that of conference room was very steepy. The humidities of bridge and restaurant were unstable because of outdoor-contact and cooking, respectively. (4)The temperature and humidity of ECR(Engine Control Room) which was designed to supply heating and cooling by PAC(Package Air Conditioner) were directly affected by the operating conditions of PAC. (5)The measured supply air volume from dampers of bridge, crew's cabin and conference room were satisfied with the design supply air volume. (5)For the improvement of the indoor thermal conditions, the temperature of crew's cabin and restaurant and the humidity of conference room, and the temperature and humidity of bridge should be controlled, respectively.

• Journal of Environmental Science International
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• v.21 no.1
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• pp.11-21
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• 2012

This study investigated the characteristics of selected volatile organic compounds(VOCs) in newly-finished residential buildings, before the occupants moved in. This investigation was carried out by measuring the indoor and outdoor concentrations of selected VOCs before the occupants moved in and by utilizing an indoor mass balance model. Among 25 target VOCs, five aromatics(benzene, ethyl benzene, toluene, m,p-xylene, and o-xylene) were detected in all samples of both indoor and outdoor air. Toluene was most abundant VOC in the indoor air of new apartments, with a median value of 168 mg $m^{-3}$. Unlike other VOCs, halogenated compounds would not be significantly emitted from building materials. The indoor air concentrations of all selected VOCs, except for 1,3,5-trimethyl benzene, exhibited significant correlations each other, while for outdoor air concentrations, five aromatics only were significantly correlated between them. The emission rate of toluene was higher for the current study(median value, 76.8 mg $m^{-2}\;h^{-1}$) than for a previous study, while the emission rates of limonene, a-pinene and b-pinene(geometric means of 2.4, 13.8 and 9.6 mg $m^{-2}\;h^{-1}$, respectively) were lower and the emission rates of m,p-xylene and 2-butanone(geometric means of 10.9 and 21.3 mg $m^{-2}\;h^{-1}$, respectively) were similar. Although there were a few exceptions, the emission strengths are likely proportional to indoor temperature, and appear to reversely proportional to air exchange rate.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.39 no.1
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• pp.1-6
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• 2002

In this paper, we propose temperature inference system for indoor and outdoor temperature of the Air-Conditioner with limited sensors. The proposed system based on the network theory of biological immune system consists of indoor and outdoor temperature inference process. It is designed that on-line temperature inference is possible. This system is admirable for unlearned data as well as given input data by making efficient use of previous information.

• Journal of the Korean housing association
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• v.21 no.3
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• pp.1-9
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• 2010

The purposes of this study were to determine the actual state of indoor environments of solitary elderly houses in the rural district during winter and to analyze the relationship between the influencing factors and indoor physical elements. Field surveys consisted of measurements of physical elements, observations of living factors, and resident's responses in interviews. Field surveys were carried out in 4 houses from $28^{th}$ of February to $2^{nd}$ of March 2008. The elements measured were air temperature, relative humidity, floor temperature, seating-place temperature, CO2 concentration, CO concentration, and illumination. The results showed that the average indoor temperature for houses was $13.5{\sim}22.5^{\circ}C$, relative humidity was 30.6~55.4%, floor temperature was $13.9{\sim}24.0^{\circ}C$, temperature when seated was $27.6{\sim}51.1^{\circ}C$, $CO_2$ concentration was 1434.6~3305.5 ppm, CO concentration was 2.8~8.4 ppm, and illumination was 31.0~96.7 lux. The residents' clothing values were 1.10~1.78 clo. The environment was evaluated as being in an unsuitable state, and it was revealed that the main reason was the lack of heating and ventilation.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.11a
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• pp.452-457
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• 2008

The purposes of this study were to determine the actual state of indoor environment and to analyze the relationship between the living factors and indoor physical elements in solitary elderly houses at rural district during winter. The field surveys were consisted of measurements of physical elements, observations of living factors, and interviews of resident's responses. The field surveys were fulfilled in 4 houses from February to March 2008. Measuring elements were air temperature, relative humidity, floor temperature, seated place temperature, $CO_2$, CO, and illumination. The results showed that the average of indoor temperature for houses was $13.5{\sim}22.5^{\circ}C$, relative humidity was $30.6{\sim}55.4%$, floor temperature was $13.9{\sim}24.0^{\circ}C$, seated place temperature was $27.6{\sim}51.1^{\circ}C$, $CO_2$ was $1434.6{\sim}3305.5ppm$, CO was $2.8{\sim}8.4ppm$, illumination was $31.0{\sim}96.7lux$. The residents' clothing values were $1.10{\sim}1.78clo$. Most of the residents' subjective responses were in discord with the physical elements. It was evaluated to be uncomfortable state, and the main reason was revealed lack of heating and ventilation.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1267-1271
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• 2009

In the present study, performance characteristics on environment change of A/C applied fin-tube and PF heat exchangers were experimentally investigated. Capacity and COP changing an outlet air velocity, an indoor/outdoor temperature and a relative humidity were obtained. Air－enthalpy calorimeter was used. As the air velocity, indoor temperature and relative humidity increase, capacity and COP increase. PF A/C has smaller refrigerant weight than the fin-tube A/C. The performance of PF-2 A/C with the squarer fin was more excellent than that of PF-1 A/C with the triangler fin.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.8 no.3
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• pp.19-28
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• 2012

In a heat only boiler system of a steam power plant, outdoor air required for combustion is made to pass through indoor space for increasing the boiler efficiency. Due to heat generated by various equipments, temperature of the air that enters the boiler will increase resulting in combustion efficiency. If the outdoor air temperature is low, however, this will cause freezing and bursting of pipes which are filled with water. It is especially fatal to small diameter pipes and pipes connected to measuring instruments. The purpose of this study is find operation and outdoor conditions where this phenomena can happen and also establish preventive measures to avoid this problem.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.7
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• pp.470-477
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• 2008

The near-optimal control algorithm for central cooling system has been developed for minimizing energy consumption while maintaining the comfort of indoor thermal environment in terms of the environmental variables such as time varying indoor cooling load and outdoor temperatures. The optimal set-points of control parameters with near-optimal control are supply air and chilled water temperatures. The near optimal control algorithm has been implemented by using LabVIEW program in order to analyze energy performance for central cooling control system.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.6
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• pp.898-902
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• 1999

During summer season, the weather condition of Korea is hot and humid. So humidity elements are very important relating to building envelope condition. The purpose of this investigation is to measure and analyze characteristics of summer's environmental elements such as relative humidity, dry bulb temperature and air velocity in the clay/cement envelope materials using a granite dome model. According to the variation of exterior humidity, the state of interior relative humidity for clay model has an equal tendency, although a little range of variation is shown in comparison to the cement model.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.591-596
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• 2008

The present study has been conducted to study the performance of dedicated outdoor air handling unit in central and personal air-conditioning. With conventional central and personal air-conditioning systems which are designed according to the maximum load, humidity increase above comfort level can not be avoided as the cooling load decreases. The adoption of dedicated outdoor air handling unit, however, can solve this problem. Moreover, the dedicated outdoor air handling unit has the characteristics of anti-bacteria due to dry coil, energy saving and good indoor air quality. During cooling seasons, dedicated outdoor air handling unit can save energy up to 30% than the conventional cooling+reheating system for controlling both temperature and humidity.