• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.8
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• pp.612-620
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• 2012

High economic growth causes increase of the building energy consumption. The energy consumption for HVAC system accounts for 40~50% of the whole building consumption. The trend for building is large-scale and high-rise. Because of the trend, the energy consumption is becoming bigger than before. Nowadays, HVAC system design are recognized as the solution for a energy-saving. This paper is focused on the energy performance evaluation of central air-conditioning system(water-based) and system air-conditioning that were applied to the office building. The systems are modeled and simulated by using EnergyPlus Software 6.0. After the Simulation, annual cooling and heating energy consumption were calculated. It was found that the system air-conditioning can reduce the energy consumption approximately 55.24% annually compared with the central air-conditioning system(water-cooled). In addition, about 46.13% of annual operating costs can be reduced by use of system air-conditioning.

• Transactions on Electrical and Electronic Materials
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• v.8 no.1
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• pp.26-31
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• 2007

The goal of this study is to determine if High Pressure Micro Jet (HPMJ) conditioning can be used as a substitute for, or in conjunction with, conventional diamond pad conditioning. Five conditioning methods were studied during which 50 ILD wafers were polished successively in a 100-mm scaled polisher and removal rate (RR), coefficient of friction (COF), pad flattening ratio (PFR) and scanning electron microscopy (SEM) measurements were obtained. Results indicated that PFR increased rapidly, and COF and removal rate decreased significantly, when conditioning was not employed. With diamond conditioning, both removal rate and COF were stable from wafer to wafer, and low PFR values were observed. SEM images indicated that clean grooves could be achieved by HPMJ pad conditioning, suggesting that HPMJ may have the potential to reduce micro scratches and defects caused by slurry abrasive particle residues inside grooves. Regardless of different pad conditioning methods, a linear correlation was observed between temperature, COF and removal rate, while an inverse relationship was seen between COF and PFR.

• Journal of The Korea Institute of Healthcare Architecture
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• v.24 no.3
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• pp.29-38
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• 2018

Purpose: Space planning to cope with the changing function of the hospital is essential in hospital architecture. In order to do so, it is vital that the paradigm shifts from hospital design focused on purpose toward hospital design focused on system. Not only space planning but also air-conditioning plan, which is most closely related to the operation and maintenance of hospital facilities; and the environment of hospital users, should be able to respond to changes with ease. Thus this study is to provide fundamental data of the air-conditioning plan for the hospital design focused on system by analyzing the concept and characteristics of the air-conditioning plan in the recent hospital architecture planning. Results: As a result of this study, in the air conditioning plan for the hospital architecture planning, the most important are the location relation among the departments the air handling unit room and the air handling unit manage and the air conditioning zoning setting according to the air conditioning system. Therefore, for the hospital architecture planning focused on system, it is necessary to establish the air conditioning setting that can accommodate changeable environment of departments and accordingly the appropriate area range of the air conditioning zoning and the plan for the location of the air handling unit should be considered. Implications: Thereby aims to provide fundamental data on air handling unit zoning planning in the hospital architecture planning.

• Journal of Biosystems Engineering
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• v.27 no.1
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• pp.51-58
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• 2002

The goal of this research was to an optimum conditions for the brown rice conditioning from data of milling characteristics after conditioning of the brown rice. The range of the initial moisture content of the sample was 13%, 14%, and 15%, the range of the increment of the moisture content was 0.4% and 0.8% with respect to the initial moisture content, and a ripe time after conditioning was eight hours. The results obtained from this research can be summarized as fellows. 1 The crack ratio after conditioning the brown rice with the initial moisture content was increased as the initial moisture content decreased and increment of the moisture content increased. The crack ratio of the milled rice was increased than that of the non-conditioned brown rice and decreased with the conditioned brown rice with the increment of the moisture content of 0.4% and 0.5%. 2. The broken rice ratio after conditioning the brown rice with the initial moisture content was a little higher than that of the non-conditioned brawn rice. The broken ratio of the conditioned brown rice with the increment of the moisture content of 0.4% was increased around 0.2∼0.4% with respect to the non-conditioned brown riced and the broken ratio of the brown rice was high with increased amount of water sprayed during conditioning process. 3. The moisture content of the milled rice after conditioning the brown rice with the initial moisture content increased around 0.3∼0.8% with respect to the non-conditioned milled rice. 4. The electric energy consumption on milling process with the conditioned brown rice by the initial moisture content was decreased 3.4∼39.1% with respect to the non-conditioned brown rice.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2270-2273
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• 2003

Fuzzy logic control has been widely implemented in air conditioning and ventilation systems which has uncertainty or high robust system. Since the dynamic behaviors of the systems contain complexity and uncertainty in its parameters , several fuzzy logic controllers had been implemented to control room temperature in the field of air conditioning system. In this paper, the fuzzy logic control has been developed to control room temperature and humidity in the precision air conditioning systems. The nonlinear mathematical model was formulated using energy and continuity equations. MATLAB was used to simulate the fuzzy logic control of the multi-variable air conditioning systems. The simulation results show that fuzzy logic controller can reduce the steady-state errors of the room temperature and relative humidity in multivariable air conditioning systems. The offset are less than 0.5 degree Celsius and 3 percent in relative humidity respectively under random step disturbance in heating load and moisture load respectively

• International Journal of Air-Conditioning and Refrigeration
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• v.14 no.1
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• pp.1-6
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• 2006

For the purpose of processing weather data for air conditioning equipment de sign in Busan area Korea, this study collected weather observations made by Busan weather Administration from 1970 to 2003, and then established external conditions for heating and air-conditioning design. For changes of temperature in external conditions for design, the highest temperature had little changed, whereas the lowest had been on the rise as the years went by through the 1970s, 1980s, 1990s, and 2000s, but insolation has a little lessened. Absolute humidity does not show a significant change but an incessant rise.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.6
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• pp.495-501
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• 2003

Control algorithms for the absorption air conditioning system may be developed by using dynamic models of the system. The simplified effective dynamic models, which can predict the dynamic behaviors of the system, may help to develop effective control algorithms for the system. In this study, control algorithms for an absorption air conditioning system were developed by using a dynamic simulation program. A cooling water inlet temperature control algorithm, a chilled water outlet temperature control algorithm, and a supply air temperature control algorithm, were developed and analyzed. The steepest descent method was used as an optimal algorithm. The simulation results showed energy savings and the effective controls of an absorption air conditioning system.

• International Journal of Air-Conditioning and Refrigeration
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• v.11 no.3
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• pp.125-131
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• 2003

The fault detection and diagnosis technology may be applied in order to decrease the energy consumption and the maintenance cost of the air-conditioning system. In this paper, two fault detection methods were considered. One is a generic neural network, and the other is an moving average neural network. In order to compare the performance of fault detection results from these methods, two different types of faults in an air-conditioning system were applied. These are the condenser 30% fouling and the evaporator fan 25% slowdown. Test results showed that the moving average neural network was more effective for the detection of partial faults in the air-conditioning system.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.9
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• pp.881-888
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• 2004

Control algorithms for a dual source chiller air conditioning system were developed. These are control algorithms for the supply air temperature control, the supply header chilled water temperature control, the chiller chilled water temperature control, and the cooling tower water temperature control. These algorithms were analyzed by using a dynamic simulation program. Simulation results showed the energy savings and the satisfactory controls of an absorption and centrifugal chiller air conditioning system. Therefore, control algorithms developed for this study may effectively be used for the improved controls of the dual source chiller air conditioning system.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.11
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• pp.994-1003
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• 2000

Control algorithms for the absorption air conditioning system may be developed by suing dynamic models of the system. The simplified effective dynamic models, which can predict the dynamic behaviors of the system, may help the development of effective control algorithms for the system. In this study, a dynamic simulation program for the absorption air conditioning system was developed. Dynamic models for an absorption chiller, a cooling tower, an air handling unit, a boiler, a three way valve, a controller, and a duct were developed and programed. Control algorithms for the absorption chiller, the cooling tower, and the air handling unit were selected, and analyzed to show the effectiveness of dynamic models. From the simulation results, it may be concluded that this simulation program may be effectively used for the development of optimal control algorithms of the absorption air conditioning system.