• Land and Housing Review
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• v.6 no.4
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• pp.231-237
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• 2015

Recently, It has been much interest in modular housing construction. so, The purpose of this study was to investigate the characteristics of the indoor air quality in modular mock-up housing. We measured indoor air quality(formaldehyde, benzene, toluene, ethylbenzene, xylene, styrene) of two modular mock-up units that built-in furniture is installed and uninstalled. As a result, the pollutants of built-in furniture installed unit were emitted more than built-in furniture uninstalled unit. But after bake-out and ventilation, emission concentrations of two modular mock-up units were similar and were below Indoor Air Quality recommendation standards. Built-in furniture is likely to affect the emission concentration of toluene

• KIEAE Journal
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• v.4 no.3
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• pp.187-194
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• 2004

In many other buildings, hospital is very important because of its function and purpose. A proper building service systems including heating, cooling, ventilation and plumbing systems is required in hospial. Besides, a special systems like medical gas, vacuum cleaning systems are required to prevent contamination as well as cure a patient in hospital. Ventilation is very important method to keep the indoor pressure and clean class. There are some specific rooms to consider clean class and indoor pressure in the general hospital. In this article, specific rooms were set to operating room, laboratory, ICU, isolation unit, and sterilizer room. In this case study, design factors of ventilation system, including air changes of OA and TA, indoor pressure, clean class, filter, and material of system, of specific rooms in hospital were proposed through a literature research and a design examples review.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.584-589
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• 2008

It is known that slab thermal storage which uses concrete slab as thermal material is effective in the load leveling and using the nighttime electric power. The temperature distribution is not constant in plenum in thermal storage time by beams, ducts such as several factor. It is considered that this fact will effect on efficiency of thermal storage and indoor thermal environment. The purpose of this paper is to examine the thermal environment inside plenum. A macro model was made for the analysis of indoor thermal environment as the first step. The flow rate distribution and temperature distribution of object room model was examined by use of basic equations such as airflow by the pressure difference between unit cells, heat flow by air and heat transfer.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.67-70
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• 2006

For a long time the GSM and GPS world has been living side by side. There have been some half hearted attempts to invoke the GPS unit into GSM units but performance and usability has suffered. The A-GPS approach is interesting and we wanted to verify general performance for fleet application and alarm/emergency situations. The result is now promising but still more to enhancements are anticipated. We achieved near acceptable availability (${\sim}70%$) under indoor conditions. Accuracy was as anticipated (50-100 meter) as we are using reflected signals. Time to first fix is in general good in outdoor conditions but too long for indoor conditions (45-60 seconds). We would like manufactures to put some more effort to get better performance in the future as test with Nordnav high sensitivity measurement system proves that conditions indoor are at a level where better performance should be possible.

• Journal of the Korean housing association
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• v.19 no.4
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• pp.97-105
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• 2008

The purposes of this study were to determine the actual state of the indoor thermal environment in apartment units and to analyze the relationship between the living factors and indoor thermal elements. The field surveys consisted of measurements of physical elements and observations of living factors. In addition, the residents of 20 apartment units were interviewed to survey their subjective response. Field surveys were carried out from January to March 2007. Measuring elements were air temperature, globe temperature, and relative humidity. The results showed that the average of indoor temperature for the houses was $21.2{\sim}27.2^{\circ}C$, while 4 houses exceeded the comfort zone. The average of globe temperature for the houses was $21.3{\sim}27.5^{\circ}C$, while 6 houses exceeded the comfort zone. The mean relative humidity was $19.5{\sim}58.8%$, which is a relatively dry condition. The residents' average clothing value was $0.39{\sim}0.89$ clo(average 0.68 clo). The average thermal sensation vote on each room was $4.2{\sim}4.8$, which is 'neutral' to 'slightly warm'. Living factors had significant effect on indoor temperature in regression analysis were ventilation time(outdoor air exchange), opening time of door through balcony, and gas cooker use time.

• Journal of the Korean Solar Energy Society
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• v.32 no.6
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• pp.141-148
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• 2012

Ceiling cassette type air conditioner has been a main stream as a heating/cooling system recently in school, Korea. In this study, indoor thermal environments made by ceiling cassette type air conditioner were investigated by CFD simulation. Concentrations of $CO_2$ were investigated by a field measurement. Indoor thermal environment with the velocity inlet angle of $45^{\circ}$ from the ceiling in heating season was very ununiform so that thermal area was divided into two parts those the one is window side which is cold, and the other is corridor side which is hot. In cooling season under the same condition, there are areas too hot or too cold. If the velocity inlet angle is set in $30^{\circ}$ from the ceiling, indoor thermal environments was improved greatly in cooling season and heating season, too. Also, from the field measurement of $CO_2$ concentrations, it was suggested to install ventilators with proper air volume considered the number of class students.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.6
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• pp.903-908
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• 2011

The purpose of this paper is to provider an indoor location measuring method, apparatus and Service available for mobile wireless network. This paper introduces positioning technology such as Basic Technology Element and QoS(Quality of Service) etc. of WPS(WiFi Positioning System) for mobile wireless network. An apparatus for sectionalizing an indoor area for indoor location measurement includes several steps. For example, a sector number input step, a sectionalization calculating step, a storing unit step etc. Also, This paper show advance Indoor positioning result.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.04a
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• pp.281-284
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• 2008

The purposes of this study were to make clear the present condition of indoor thermal environment in apartment units and to analyze the relation of the living factors with indoor thermal elements. The field surveys consisted of measurements on physical elements and observations on living factors and interview on resident's subjective responses were carried out in 20 apartment units. The field surveys were carried out during the $January{\sim}March$ 2007. Measuring elements were air temperature, globe temperature, and relative humidity. As results, the averages of indoor temperature each houses were $21.2{\sim}27.2^{\circ}C$, the number of houses exceed the comfort zone were 4. The averages of globe temperature each houses were $21.3{\sim}27.5^{\circ}C$, 6 houses exceeded the comfort zone. The means of relative humidity were $19.5{\sim}58.8%$, relatively dry condition. The clothing value of residents were $0.39{\sim}0.89$ clo(average 0.68 clo). The average of thermal sensation ratings each room were $4.2{\sim}4.8$, 'neutral'$\sim$'slightly warm'. The results of regression analysis on relations of living factors with the thermal elements are as follow; ventilation time(outdoor air exchange), door opening time with balcony, and gas cooker use time had significant effect on indoor temperature.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.618-622
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• 2007

In the present study, the cooling and heating operation characteristics of a multi-heat pump have been experimentally investigated for the number of the indoor units(A, B, C) and the operating conditions. The heat pump was controlled by an inverter scroll compressor. The performance of the heat pump was measured by the multi-calorimeter of an air enthalpy method. Cooling and heating capacities and COPs were obtained at the cooling and heating temperature conditions and the setting temperatures of an indoor unit. With increasing the operation frequency of the compressor, the cooling and heating capacities of the heat pump increased linearly. The operation frequency region of the compressor was different as the combination of the indoor unit and the cooling/ heating condition.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.364-369
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• 2007

A system heat pump provides the benefits of comfort, energy conservation and easy maintenance. Recently, the system heat pump has been employed in small and medium-sized buildings. However, the performance data and control algorithm for system heat pump are limited in literature due to complicated system parameters and operating conditions. In the present study, the performance of a system heat pump with two indoor unit is measured by varying indoor loads, EEV opening, and compressor speed. In addition, the integral optimum regulator which includes MIMO control algorithm is proposed. The capacity modulation and optimum capacity for each indoor unit can be adjusted by utilizing the EEVs opening and compressor speed. The proposed scheme shows appropriate control performance at test conditions.