• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.509-513
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• 1992

This paper investigates the EEG waveform distortions caused by the transient responses of various types of signal conditioning filters, which are generally introduced for automated analysis of EEG. This study explicitly simulates the filter responses to the typical EEG waveform models, and compares the distortions. The filter distortion effects are also illustrated with the experiments on real EEG signals.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.8 no.1
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• pp.55-64
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• 1996

A numerical model of refrigerant flow through a capillary tube is developed, which considers the effects of underpressure for vaporization, kinetic energy, and roughness of capillary tube. The numerical model is based on homogeneous flow assumptions for the two-phase flow region. A characteristic chart of HFC refrigerants flow through capillary tubes and correction factor chart of geometry and relative roughness of capillary tube to select a proper capillary for refrigerating machines using alternative refrigerants is presented by this numerical model.

• International Journal of Air-Conditioning and Refrigeration
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• v.13 no.3
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• pp.152-157
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• 2005

This paper reviews the literature on the performance of fin-and-tube heat exchangers under frosting and defrosting conditions. The effects of frosting and defrosting on the following parameters were discussed: frost growth, overall heat transfer coefficient, surface roughness, and surface characteristics on the heat exchanger. Comparisons of the experimental results and empirical correlations that were obtained from open literature were presented. In addition, a review of the defrosting methods was conducted.

• International Journal of Air-Conditioning and Refrigeration
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• v.12 no.2
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• pp.97-107
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• 2004

Wall/floor intersection is important parts of a building envelope system. These intersections can be sources of thermal bridging effects and/or moisture condensation problems. This paper provides a detailed analysis of the thermal performance of wall/floor intersection. In particular, two-dimensional steady-state and transient solutions of the heat conduction within the wall/floor joint are presented. Various insulation configurations are considered to determine the magnitude of heat transfer increase due to wall/floor joint construction.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.17 no.4
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• pp.377-381
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• 1988

Effects of thermal resistance of mold during freezing processes have been investigated. Saturated liquid is chosen to present one-dimensional quasi-steady solution and this solution is compared with numerical solutions. Front tracking finite element method has been applied for the numerical solutions. Results show that mold should be considered as well as phase change material except the cases when the very thin mold with relatively high thermal conductivity is used.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.27 no.6
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• pp.541-547
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• 1998

공기 중에 존재하는 미생물(바이오에어로졸, bio-aerosol)은 많은 질병 발생의 원인이다. 의학계에서는 바이오에어로졸과 공기 매개성 질병의 전파와의 연관성이 잘 알려져 있다. 특히 결핵, 수두, 홍역, 천연두의 발병은 공기를 통한 질병 전파의 중요성을 확인시켜 준다. 그러나 IAQ(indoor air qualify)의 영향은 최근에서야 조사되었다. 보건의료기관과 연구실험실에서는 세균과 진균의 감염이 HVAC 시스템을 통해서 종종 일어난다. 유사한 IAQ연구에서는 바이오에어로졸이 빌딩증후군과 같은 빌딩과 관련된 질병(building-related illness, BRI), 감염, 중독성 증상, 민감성 질병과 1차적으로 연결되어 있음을 발견되었다.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.5 no.4
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• pp.281-287
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• 1976

Solar Radiation is effected by the astronomical condition, the collector inclination, the air and the climate conditions before it reaches an earth surface. Based on the data which have been collected and recorded by the Central Meteorological Office and other resources, the effects of those conditions in Korea are analysed and appraised in this report.

• International Journal of Air-Conditioning and Refrigeration
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• v.12 no.4
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• pp.192-197
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• 2004

A capillary tube, which is a common expansion device in small sized refrig-eration and air-conditioning systems, should be redesigned properly to establish an optimum operation cycle of a refrigerating system with alternative refrigerants. Based on experimental data for R-22, R-290, and R-407C, an empirical correlation is developed to predict mass flow rate through capillary tubes. Dimensionless parameters are derived from the Buckingham Pi theorem, considering the effects of operating conditions and capillary tube geometry on mass flow rate. Approximately $97\%$ of the present data are correlated within a relative deviation of $\pm\;10\%.$ The present correlation also predicts the data obtained from open literature within $\pm\;15\%.$ In addition, rating charts of refrigerant flow rate for R-12, R-22, R-134a, R-152a, R-407C, R-410A, R-290, and R-600a are developed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.4
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• pp.542-548
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• 1999

Instead of testing split air conditioners, an empirically based calculation procedure may be used to estimate the Energy Efficiency Ratio at ARI A test conditions. Typically, the system involving the indoor unit well sold and the given outdoor unit is called the matched system. All other systems involving a given outdoor unit and other indoor units are called the mixed systems. To estimate the EER(A) for the mixed systems, EER(A) for the matched system must be known, Generally, the EER(A) for the matched system is known. This procedure relies on independent measurements and calculations made on an outdoor unit in conjunction with a matched indoor and a mixed indoor coil. A heat pump simulation model was used to quantify the effects of individual system components on the system performance. The procedure is applicable to all air-conditioning units having rated cooling capacities less than 19,000W and charged with refrigerant 22.

• 유체기계공업학회:학술대회논문집
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• 2004.12a
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• pp.691-696
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• 2004

Recently, it is required that the automotive air conditioning system must keep the cabin temperature comfortable in spite of engine speed, and Improve the fuel consumption during all the seasons. To satisfy these requirements, the variable displacement swash plate type compressor with control pressure valve is developed. In this study, the effects of two type valves, suction pressure control valve and differential pressure control valve, on the performance of swash plate type compressor has been investigated experimentally.