• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.123-125
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• 2021

Pregnant women's psychological health affects the health of the fetus. Therefore, health care for pregnant women is essential for a healthy fetus. One of the symptoms of pregnancy among many pregnant women is the depression of emotional ups and downs. One way to relieve this depression is to use light therapy and color therapy by using lighting. Adjust the color temperature of the light so that it affects the emotions through color. For example, ceiling lights in car dealerships are set up like a sun-light, or low color temperature are used to create a comfortable mood in facilities like spas. In this paper, we use image sensors to identify the psychological state and change the color temperature of the lighting in real time. The study was conducted to relieve postpartum depression by using the psychological effects of pregnant women with easily purchased lighting devices.

• Journal of the Korean Wood Science and Technology
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• v.39 no.3
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• pp.230-237
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• 2011

The study was performed to investigate the characteristics of charcoal and temperature change of a kiln's inner and outer walls in carbonization process using improved kiln. In this kiln system, carbonization process was completed in eight days. In the kiln, the ignition temperature was kept about $720^{\circ}C$. And then the temperature were increased gradually prior to be refined. Finally, the temperature in refining process was reached to maximum point, $1,000^{\circ}C$. In the chimney, the temperature was increased gradually from $90^{\circ}C$ at ignition to $750^{\circ}C$ at refining. The temperature change of the kiln wall resembles a temperature change progress curve during a carbonization process. The highest temperature of the kiln wall that appeared by a carbonization process was around $500^{\circ}C$. As a result of having measured an inner wall and the outer wall of the kiln using an infrared thermography camera, it was judged with there being considerable latent heat on kiln wall and ceiling. Fixed carbon contented of charcoal was 85.9~89.9%. Refining degree of charcoal, hardness, calorific value and pH were l, 12, 7,047~7,456 kcal/kg, 9.0~9.9, respectively. The yield of wood charcoal was 13.8%, and compared to conventional kiln's yield increased 1.5%.

• Journal of Animal Environmental Science
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• v.8 no.2
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• pp.79-86
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• 2002

This study was conducted to collect basic data about the effects of ventilation types on the interior environment of the enclosed farrowing-nursery pig house in Anseong, Icheon and Jeungpyong. Surveyed ventilation types in the enclosed farrowing-nursery pig house are classified in to 4 types. In V1 type, air enters through a planar slot inlet placed on the juncture of the entering wall and exit through the chimney fan outlet; in V2 type, air enters through a perforated ceiling inlet and exits chimney fan outlet(V2); in V3 type, air enters through a circular duct inlet and exit chimney fan outlet(V3); in V4 type, enters through a circular duct inlet and exits side wall exhaust fan outlet(V4). Temperature, relative humidity, air velocity and ammonia concentration($NH_3$) were measured in the interior of swine building in the summer. Interior temperature was not remarkably different in all ventilation types in this study. However, temperature of the V4 was somewhat lower than that of the other types. Air velocity of the V4 was higher and $NH_3$ concentration of the V4 was lower than those of other ventilation types. It is suggested that the V4 ventilation type be applicable in the enclosed farrowing-nursery pig house in Korea.

• Journal of the Korean Society for Railway
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• v.9 no.3 s.34
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• pp.291-297
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• 2006

The present study investigated the effect of fire suppression using a mid-low pressure water mist in a carriage fire. The fire extinguishing time and temperature distributions below ceiling in the enclosed compartment of $2.9m{\times}2.8m{\times}5.0m$ were measured by stopwatch and k-type thermocouples for various fire positions. The numerical simulations were extensively performed using. Fire Dynamics Simulator(FDS, Ver. 4.0) code and the predictions were compared with experimental data. The prediction results showed good agreement with the measured maximum temperature in the all cases. Whereas the predicted temperature was about $40^{\circ}C$ higher than the measured one after operating of water mist. The predicted fire extinguishing times were compared with those of measured data. Fires are extinguished within 200 seconds at the experiment in Case 2 and Case 3. But in Case 1 fire was not extinguished in the numerical simulation. The reason of the discrepancy between predicted and measured data was that a simple suppression algorithm has been implemented in FDS. Also, various databases of fire properties for combustible materials and more elaborate model considering the water mist were required fur better predictions of the cooling and suffocation effect.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.10
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• pp.387-393
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• 2016

A ground source heat pump system maintains a constant efficiency due to its stable heat source and radiant heat temperature which provide a more effective thermal performance than that of the air source heat pump system. As an eco-friendly renewable energy source, it can reduce electric power and carbon dioxide. In this study, we analyzed one year of data from a web based remote monitoring system to estimate the thermal performance of GSHP with the capacity of 3RT, which is installed in a low energy house located in Daejeon, Korea. This GSHP system is a hybrid system connected to a solar hot water system. Cold and hot water stored in a buffer tank is supplied to six ceiling cassette type fan coil units and a floor panel heating system installed in each room. The results are as follows. First, the GSHP system was operated for ten minutes intermittently in summer in order to decrease the heat load caused by super-insulation. Second, the energy consumption in winter where the system was operated throughout the entire day was 7.5 times higher than that in summer. Moreover, the annual COP of the heating and cooling system was 4.1 in summer and 4.2 in winter, showing little difference. Third, the outlet temperature of the ground heat exchanger in winter decreased from $13^{\circ}C$ in November to $9^{\circ}C$ in February, while that in summer increased from $14^{\circ}C$ to $17^{\circ}C$ showing that the temperature change in winter is greater than that in summer.

• Journal of the Korean Wood Science and Technology
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• v.2 no.2
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• pp.32-34
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• 1974

The important results which have been obtained in the investigation can be recapitulated as follows. 1. As demonstrated by the experimental results and analyses concerning their effects in the on-ground type mushroom house, the constructions in relation to the side wall and ceiling of the experimental house showed a sufficient heat insulation on effect to protect insides of the house from outside climatic conditions. 2. As the effect on the solar type experimental mushroom house which was constructed in a half basement has been shown by the experimental results and analyses, it has been proved to be effective for making use of solar heat. However there were found two problems to be improved for putting solar house to practical use in the farm mushroom growing: (1) the construction of the roof and ceiling should be the same as for the on ground type house, and (2) the solar heat generating system should be reconstructed properly. 3. Among several ventilation systems which have been studied in the experiments, the underground earthen pipe and ceiling ventilation, and vertical side wall and ceiling ventilation systems have been proved to be most effective for natural ventilation. 4. The experimental results have shown that ventilation systems such as the vertical side wall and underground ventilation systems are suitable to put to practical use as natural ventilation systems for farm mushroom house. These ventilation systems can remarkably improve the temperature of fresh air which is introduced into the house by heat transfers within the ventilation passages, so as to approach to the desired temperature of the house without any cooling or heating operation. For example, if it is assuming that X is the outside temperature and Y is the amount of temperature adjustment made by the influence of the ventilation system, the relationships that exist between X and Y can be expressed by the following regression lines. Underground iron pipe ventilation system. Y=0.9X-12.8 Underground earthen pipe ventilation system. Y=0.96X-15.11 Vertical side wall ventilation system. Y=0.94X-17.57 5. The experimental results have 8hown that the relationships existing between the admitted and expelled air and the $CO_2$ concentration can be described with experimental regression lines or an exponent equation as follows: 5.1 If it is assumed that X is an air speed cm/sec. and Y is an expelled air speed in cm/sec. in a natural ventilation system, since the Y is a function of the X, the relationships that exist between X and Y can be expressed by the regression lines shown below: 5.2 If it IS assumed that X is an admitted volume of air in $m^3$/hr. and Y is an expelled volume of air in $m^3$/hr. in a natural ventilation system, since the Y is a function of the X, the relationships that exist between X and Y can be expressed by the regression lines shown below. 5.3 If it is assumed that expelled air speed in emisec. and replacement air speed in cm/sec. at the bed surface in a natural ventilation system are shown as X and Y. respectively, since the Y is a function of the X. the relationships that exist between X and Y can be expressed by the following regression line: GE(100%)-CV (50%) ventilation system. Y=-0.54X+0.84 5.4 If it is assumed that the replacement air speed in cm/sec. at the bed surface is shown as X, and $CO_2$ concentration which is expressed by multiplying 1000 times the actual value of $CO_2$ % is shown as Y, in a natural ventilation system, since the Y is a function of the X, the relationships that exist between X and Y can be expressed by the following regression line: GE(100%)-CV(50%) ventilation system. Y=114.53-6.42X 5.5 If it is assumed that the expelled volume of air is shown as X and the $CO_2$ concencration which is expressed by multiplying 1000 times the actual of $CO_2$% is shown as Y in a natural ventilation system, since the Y is a function of the X, the relationships that exist between X and Y can be expressed by the following exponent equation: GE(100%)-CV(50%) ventilation system. Y=$127.18{\times}1.0093^{-x}$ 5.6 The experimental results have shown that the ratios of the cross sectional area of the GE and CV vent to the total cubic capacity of the house, required for providing an adequate amount of air in a natural ventilation system, can be estimated as follows: GE(admitting vent of the underground ventilation) 0.3-0.5% (controllable) CV(expelling vent of the ceiling ventilation) 0.8-1.0% (controllable) 6. Among several heating devices which were studied in the experiments, the hot-water boilor which wasmodified to be fitted both as hot-water boiler and as a pressureless steam-water was found most suitable for farm mushroom growing.

• Transactions on Electrical and Electronic Materials
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• v.10 no.2
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• pp.35-39
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• 2009

A novel Helmholtz coil inductively coupled plasma(H-ICP) etcher is proposed and characterized for deep nano-scale CMOS technology. Various hardware tests are performed while varying key parameters such as distance between the top and bottom coils, the distance between the chamber ceiling and the wafer, and the chamber height in order to determine the optimal design of the chamber and optimal process conditions. The uniformity was significantly improved by applying the optimum conditions. The plasma density obtained with the H-ICP source was about $5{\times}10^{11}/cm^3$, and the electron temperature was about 2-3 eV. The etching selectivity for the poly-silicon gate versus the ultra-thin gate oxide was 482:1 at 10 sccm of $HeO_2$. The proposed H-ICP was successfully applied to form multiple 60-nm poly-silicon gate layers.

• Journal of Biosystems Engineering
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• v.34 no.3
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• pp.161-166
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• 2009

This study was conducted to investigate the growth characteristics of cherry tomatoes in greenhouse using far infrared heating system. The far infrared greenhouse heating systems were installed in two ways on the greenhouse side wall and at the greenhouse ceiling. The heating characteristics of far infrared heating system were analyzed by investigating the heating load, internal temperature, energy consumption, growth characteristics and quality evaluation. The results were compared with heated air heating system using kerosene. The results showed that tomatoes grown in the greenhouse with the far infrared heating system had relatively better plant height, leaf length, leaf width, stem diameter than ones from the greenhouse with hot air heating system and both heating methods had no significant difference on Cherry tomato sugar contents. At the same time, the far infrared heating system reduced heating cost from 34.5 to 41.4% on comparing with hot air heating system.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.398-403
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• 2009

The theoretical bases on characteristics of heat release rate in compartment of building for scenario of smoke management are introduced and the numerical applications to simple compartment model are carried out. The growth stage which is important for smoke management design is modelled as t-squared fire curve including fire growth coefficient with related to growth rate. The conditions for the happening of flashover is presented such as $600^{\circ}C$ of temperature or $20kW/m^2$ of radiation heat flux. After the flashover happen, the fire in compartment changes to fully developed fire having the characteristics of ventilation-controlled fire. As the result of numerical analysis to simple compartment model, the time to reach 900K under ceiling for condition of medium growth is twice for condition of fast growth.

• Journal of Korean Tunnelling and Underground Space Association
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• v.6 no.2
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• pp.141-149
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• 2004

In this study, smoke movement in tunnel fire with natural and longitudinal ventilation systems has been investigated. Reduced-scale experiments were carried out under the Froude scaling using 14.55kW fire source with a wick and experimental data is obtained with 1/18 model tunnel test. Temperature profiles were measured under the ceiling and vertical direction along the center of the tunnel and poisonous gas was measured at emergency exit point. The results show that refuge time for 225m intervals of emergency exit in case of natural ventilation systems is 256 seconds and critical velocity for sufficient back-layer prevention is 2.8m/s for fire strength of 20MW.