• 한국가구학회지
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• 제20권6호
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• pp.599-604
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• 2009

For the search of unified law of moisture movement in wood, moisture distribution of Korean red pine at non-steady state was investigated. We assume that the equilibrium moisture content (EMC) in wood depends on only temperature and relative humidity, it can be control in temperature and humidity chamber. If temperature is constant and humidity or vapor pressure is changed with sin curve shape at adequate cycles, EMC in chamber can be changed as well with sin-curve shape. The setup condition of a non-steady state in humidity control chambers is a constant temperature at $20^{\circ}C$ and 15+10 sin ${\omega}t$ percent EMC. It can be found that the distribution of moisture in the specimen with varying relative humidity are illustrated various types. Moisture in wood is complicated and vibrates with the moisture sorption process. Considering a unified law of moisture movement in wood, it is considered that the most important fact is to search the method of precise diffusion & transfer coefficients.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.1065-1068
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• 2008

Concrete is still one most common construction materials even in railway structures. As structures become massive and mega-sized, the importance of early age concrete quality control becomes more significant. Among various factors, relative humidity and temperature are the primary factors governing the early age quality. Temperature raise due to cement hydration causes stress, which can develop to cracking with internal and/or external restraints. Exposure conditions including ambient temperature, humidity and wind also significantly affect the cracking behavior of early age concrete. Among many of studies on the early age concrete behavior, investigation on the variation of temperature and relative humidity internal of concrete is not common. That is in part because the difficulties in measuring the relative humidity and temperature inside the concrete. This study used a digital sensor with an appropriate logger to measure internal temperature and relative humidity. This direct measuring method is expected to provide more reliable and comprehensive data acquisition on the early age behavior of concrete.

• 환경생물
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• 제22권2호
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• pp.279-286
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• 2004

본 연구는 토지피복현황과 수림의 층위구조 등이 다양한 도시녹지를 대상으로 미기상 조절에 미치는 영향을 정성 및 정량적으로 파악하기 위해 녹지내의 기온 및 습도를 관측하였다. 그 데이터를 바탕으로 녹지내의 토지피복 현황과 그 비율, 녹적량과 기온 및 습도와의 관련성을 회귀분석 등에 의해 해석하였다. 그 결과 고온역은 포장면과 나지 주변에서, 저온역은 수림지 및 수면 주변에서 형성되었다. 또한, 수림(교목+소교목)으로 둘러싸인 수면, 소하천 주변에도 저온을 나타냈다. 습도는 기온분포에 거의 대응하는 형태로 고온역이 저습역이고, 저온역이 고습역으로 나타났다. 녹지가 미기상조절효과를 갖는 메커니즘은 토지피복비율의 종류,그 비율의 차이에 따라 미기상조절효과의 정도가 서로 달랐다. 더욱이 각 녹적량의 증가는 수고에 관계없이 모두 기온은 떨어뜨리고 습도는 상승시키는 효과를 보였다. 그 효과의 효율은 교목, 소교목, 관목의 순이다. 지금까지의 실증결과로부터 고온완화에는 수림지, 수면,초지의 순으로, 그 비율을 증가해서 배치하면 효과가 커지고, 같은 방법으로 습도의 상승에는 수면, 수림지, 초지의 순으로 그 비율을 증가해서 배치하면 효과가 높아진다. 그 효율성을 고려하면 수면, 소하천을 핵으로 그 주변은 교목 중심의 수림이 좋고, 그 층위구조는 단층림보다는 2∼3층의 혼효림이 미기상조절에 미치는 효과가 크다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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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

• KIEAE Journal
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• 제14권1호
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• pp.75-81
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• 2014

This study aims at investigating the benefit of actively controlling humidity to improve thermal comfort and energy efficiency in climate zones other than hot-dry. For this research purpose, three thermal control strategies, which adopted different initiative degrees in humidity control, were developed - i) temperature controls, ii) temperature and humidity controls, and iii) thermal sensation controls. Performance of the developed strategies were experimentally tested in a full scale mock up of an office environment. The study revealed that air temperature was better controlled in the occupied zone under the first two strategies than the thermal sensation based strategy. On the other hand, the thermal sensation-based strategy maintained thermal sensation levels more comfortably. In addition, energy consumption was significantly reduced when humidity was actively controlled for thermal comfort. The thermal sensation-based control strategy consumed significantly less electricity than the first two strategies. From these findings, this study indicated that adoption of an active humidity control system based on thermal sensation can provide increased thermal comfort as well as energy savings for summer seasons in climatic zones other than hot-dry.

• 한국전자통신학회논문지
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• 제13권4호
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• pp.851-858
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• 2018

본 논문에서는 스마트 농장의 경제성과 생산성을 제고하기 위한 스마트 농장을 위한 온습도 제어 알고리즘을 제안하였다. 스마트 농장의 기본 조건을 분석하고, 이를 기반으로 무선통신을 기반으로 하는 스마트 농장내의 센서 및 제어대상간 정보교환 시스템을 설계하였으며, 스마트 농장내의 온도, 습도 그리고 토양습도가 식물 성장에 적합하게 설정된 기준 값을 추종하도록 온습도 제어 알고리즘을 개발하였다. 제안된 설계 방법론 및 제어 알고리즘의 유효성을 검증하기 위해서 2.4GHz 무선통신 기반 소규모 스마트 농장의 프로토타입을 제작하였으며, 온습도 실험을 통해서 그들의 유효성을 확인하였다.

• 생물환경조절학회지
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• 제18권3호
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• pp.200-207
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• 2009

This study was conducted to analyze the variations of air temperature, relative humidity and pressure in a low pressure chamber for plant growth. The low pressure chamber was composed of an acrylic cylinder, a stainless plate, a mass flow controller, an elastomer pressure controller, a read-out-box, a vacuum pump, and sensors of air temperature, relative humidity, and pressure. The pressure leakage in the low pressure chamber was greatly affected by the material and connection method of tubes. The leakage rate in the low pressure chamber with the welding of the stainless tubes and a plate decreased by $0.21kPa{\cdot}h^{-1}$, whereas the leakage in the low pressure chamber with teflon tube and rubber O-ring was given by $1.03kPa{\cdot}h^{-1}$. Pressure in the low pressure chamber was sensitively fluctuated by the air temperature inside the chamber. An elastomer pressure controller was installed to keep the pressure in the low pressure chamber at a setting value. However, inside relative humidity at dark period increased to saturation level.. Two levels (25 and 50kPa) of pressure and two levels (500 and 1,000sccm) of mass flow rate were provided to investigate the effect of low pressure and mass flow rate on relative humidity inside the chamber. It was concluded that low setting value of pressure and high mass flow rate of mixed gas were the effective methods to control the pressure and to suppress the excessive rise of relative humidity inside the chamber.

• KIEAE Journal
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• 제6권1호
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• pp.57-62
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• 2006

Korean Traditional houses has been evolved and developed in many years, adopting the natural environment to control exterior conditions. These control method are various passive system of using natural materials, considering micro climate, building lay out, and these system are more natural and ecological to make the comfortable indoor climate than active systems of the present houses. This study aims to analyzed control performance of outdoor environment of five Korean traditional houses during the summer and winter. These houses are varied with lay out and floor plan to reflect the way of control for environmental condition, surveyed the reverberation time and sound level difference between rooms of the main living room and other main floored room, master room and kitchen. Especially air temperature and humidity have been measured simultaneously in each rooms to compare with outdoor condition. As a result, the variation of air temperature and humidity of most rooms are considerably static while condition of outdoors are much varied, it is showed that indoor climate has been controled with traditional soiled walls.

• 한국연초학회지
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• 제7권2호
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• pp.129-139
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• 1985

cent was carried out to study on the effect of temperature and humidity to chemical tobacco leaves during the yellowing stage. The results were follows : In the condition of high humidity and low temperature, yellowing time was delayed ; leaf color appeared lack clearness. In the higher temperature and the lower humidity during the yellowing stage : total sugar, reducing sugar and malic acid content were increased. Decomposition of nitrogenous components elevated in $38^{\circ}C$, 85%RH. Changes of total nitrogen content correlated with total curing time. Adecrease of linolenic acid with a corresponding increase of chlorogenic acid proceeded in the condition of low temperature and high humidity. In a view of tobacco quality by chemical components, the low temperature and high humidity during the yellowing stage decreased quality of tobacco leaves. It is considered to control of the proper condition of temperature and humidity during the yellowing.

• 설비공학논문집
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• 제14권7호
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• pp.607-616
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• 2002

This study has been conducted to evaluate the applicability of the control method in the dehumidification-integrated radiant floor cooling system in terms of stability of the room air temperature and the control variables through experiments. To do this, the relationship between the control variables in preventing floor surface condensation is first analyzed and the control method is predetermined through simulations. The results are as follows. First, it is necessary to determine the operation status of the dehumidification system according to the relationship between floor surface temperature and dew point temperature in the conditioned space. Second, outdoor reset with indoor temperature feedback control is better than on/off bang-bang control with respect to temperature stability in controlling the room air temperature and the possibility of energy savings. Finally, the humidity sensor can be located with the current thermostat in that there are small differences in absolute humidity in vertical distribution.