• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.769-772
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• 2008

Pores can become factors of reducing the capacity of concrete by being path of degradation factors and moisture can fill up pores inside of concrete, so evaluating the effect of unidirectional permeability due to moisture on pore structure of concrete structure is very important. Therefore, the change of pore structure in cases of 0%, 40%, 60%, 80% and 90% humidity being maintained on test specimens and in case of Lithium Silicate, which is chemical compound, being coated were evaluated. As a result, the condensation due to moisture could be confirmed since unidirectional permeability was decreased and the density of Pore Structure was improved as the percentage of water content was being increased. And, solution-type Lithium Silicate fills up pores of sizes around 1$\mu$m in the condition of carrying water and improves the density but the range of capacity improvement due to osmosis will be limited according to functional conditions.

• KIEAE Journal
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• v.13 no.4
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• pp.103-112
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• 2013

The Federal Democratic Republic of Nepal(Nepal) is one of the poorest country in the world. People in Nepal are having lots of housing problems including the lack of housing provision. Even Habitat for Humanity Nepal (HfH_Nepal) has developed various programs to diffuse ecological housing, still there are many problems due to financial and technological shortage. The purpose of this study is to verify the effects of suggestion of performance improvement for HfH_Nepal eco house with introduction of the housing situation and efforts to provide sustainable housing by HfH_Nepal in Terai plain. Ideas on CGI sheet roof with poor insulation, double panel bamboo wall and adobe brick wall which can overcome structural and waterproof flaws of the thin single panel bamboo wall. The experiment result shows that both ideas adapted to adobe brick house reduces daily temperature range 50.8% and humidity adjust effect. For the effective provision of adobe brick house, compressive strength was tested for the bricks made with locally available fiber materials. Brick with jute displayed 41.1% betterment than plain brick with closest packing condition while coconut and straw showed 25.1% and 7.9% improvement respectively. Technical and economic problems brought up during the building and experiment process were listed and countermeasures established. This kinds of building prototype houses and experiments can improve the living conditions of people in developing countries with little supplement of resources. Furthermore, consideration of locally available and affordable material can help the social and ecological sustainability in the world.

• Journal of the Korean Data and Information Science Society
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• v.26 no.3
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• pp.661-668
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• 2015

Them traffic accidents have been increased every year due to increasing of vehicles numbers as well as the gravitation of the population. The carelessness of drivers, many road weather factors have a great influence on the traffic accidents. Especially, the number of traffic accident is governed by precipitation, visibility, humidity, cloud amounts and temperature. The purpose of this paper is to analyse the effect of road weather factors on traffic accident. We use the data of traffic accident, AWS weather factors (precipitation, existence of rainfall, temperature, wind speed), time zone and day of the week in 2013. We did statistical analysis using logistic regression analysis and decision tree analysis. These prediction models may be used to predict the traffic accident according to the weather condition.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.5
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• pp.397-402
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• 2010

In this paper, we studied WVTR(water vapor transmission rate) properties of $Si_3N_4$ thin film that was deposited using TCP-CVD (transformer coupled plasma chemical vapor deposition) method for the possibility of OLED(organic light emitting diode) encapsulation. Considering the conventional OLED processing temperature limit of below $80^{\circ}C$, the $Si_3N_4$ thin films were deposited at room temperature. The $Si_3N_4$ thin films were prepared with the process conditions: $SiH_4$ and $N_2$, as reactive gases; working pressure below 15 mTorr; RF power for TCP below 500 W. Through MOCON test for WVTR, we analyzed water vapor permeation per day. We obtained that WVTR property below 6~0.05 gm/$m^2$/day at process conditions. The best preparation condition for $Si_3N_4$ thin film to get the best WVTR property of 0.05 gm/$m^2$/day were $SiH_4:N_2$ gas flow rate of 10:200 sccm, working pressure of 10 mTorr, working distance of 70 mm, TCP power of 500 W and film thickness of 200 nm. respectively. The proposed results indicates that the $Si_3N_4$ thin film could replace metal or glass as encapsulation for flexible OLED.

• Journal of Korea Foresty Energy
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• v.20 no.2
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• pp.34-40
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• 2001

This study was carried out to investigate the effects of IBA(indole-bufrric acid) on the rooting and root growth of air-layered part of Pinus thunbergii for miniature tree material. The experiment was performed on April 13 and lune 11, 2000 in the humidity controllable greenhouse condition. In April experiment, IBA treatment with 5000ppm at girdling part shortened about 20 days for rooting than those of control and 1000ppm treatment. IBA treatment in June did not affect on the period required for rooting, but the rooting of all the air-layered seedlings was faster than that of in April. On the other hand, IBA treatment in April did not affect on the number of root grown at girdling part and the root biomass, but the treatment in June increased the number of root and the root biomass of air-layered Pinus thunbergii.

• Fashion & Textile Research Journal
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• v.20 no.4
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• pp.474-481
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• 2018

For this study, we developed clothing in which textile materials that were excellent weather control function for the cold environment and we performed the human subject test with developed clothing to determine the thermal comfort. We used 2 clothing samples developed (A and B, hollow yarn+moisture absorption/quick drying yarn, 3 layers, high stretchable, heat reflection film and lamination treated) and a control sample (Ctrl.) for the human subject test and 8 adult males were used as a human subjects and environmental conditions of chamber were $0{\pm}1^{\circ}C$. $50{\pm}5%RH$, 0.3m/sec. The results were as follows: The average skin temperature and hand, thigh temperature of B were higher than B and Ctrl. (p<.05). The micro-climates of B were near to thermal comfort range which is $32{\pm}1^{\circ}C$ and $50{\pm}10%\;RH$. The chest temperature of B was significantly higher than others (p<.05). The relative humidity of B was lower than others and kept stable rather than others. The thermal sensation of B was near the "neutral" and was significantly different from Ctrl. (p<.01) and the weight loss of B was lower than Ctrl. (p<.05). The counting task and hand temperature was positively related and the counting task value of B and A is bigger than Ctrl. and that of A was bigger than Ctrl. (p<.05).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.1
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• pp.11-15
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• 1988

Square slices of sea tangle was dried in constant condition of thickness (1.54mm), air temperature $(50^{\circ}C)$, relative humidity $(30\%)$ and air velocity (0.4m/s). The shrunk surface area and the shrinking rate were investigated. The results obtained are summarized as follows : 1) Comparing the shrinking of transverse section with that of vertical section, the transverse section was proceeded more double shrinkage than vertical section. 2) The shrunk surface area curve showed nearly a linear shrinkage up to 90min of drying time. 3) The shrinking rate was rapidly increased in first falling rate period, and was largest in the early period of second falling rate period.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.6
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• pp.724-731
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• 2011

Dew generation on an outer surface is considered as an important issue to be settled in the field of home appliances. In the case of a refrigerator that is subject to the dew generation problem on the surface of an outer-door of refrigeration thread, and so as to solve this problem, the electric heater is generally used for drying the dew. However, the heater inevitably requires electrical power consumption that is one of critical issues on the refrigerator. In this study, to prevent dew generation without the heater, a method of using induced heat from room temperature was proposed. In edge sides of a door, high conductive plates are installed and received the heat from outside that is relatively high temperature, and the heat is transferred onto dew generation region. Using prototypes, performance test was conducted under a certain temperature and humidity condition. The experimental results show that the surface temperature on the dew generation region was increased about $0.3{\sim}2.5^{\circ}C$ without use of any heater.

• Journal of Mushroom
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• v.5 no.2
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• pp.81-85
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• 2007

This study was carried out to investigate the conditions of liquid culture and fruiting body formation of Cordyceps militaris using grain mediacontained the brown rice and black purple rice. Liquid mycelial growth and density of Cordyceps militaris were the highest in the medium of malt extract 0.7% and pH 5.0~5.5. The optimal condition of formation the fruiting bodies were shown to be temperature of $17^{\circ}C$, light intensity of 600 lux, $C0_2$ of 500ppm and humidity intensity of 95% produced highest amount of fruit bodies.

• Advances in concrete construction
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• v.10 no.5
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• pp.393-402
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• 2020

The given research focuses on examining the effect of relatively humidity (RH) and curing temperature on the hydrates as well as the porosity of calcium sulfoaluminate (CSA) cement pastes. Numerous tests, which consist of mercury intrusion porosimetry (MIP), thermosgravi metric (TG) and X-ray diffraction (XRD) were conducted. Various characterization techniques which include, scanning electron microscopy, Fourier transform microscopy along with X-ray diffraction evaluations were conducted on the samples to examine phase formation and crystallinity, morphology and microstructure along with bond formations and functional groups, respectively. During long-term study, the performance of concrete which consisted of limestone and flash-calcined was close to those from standard Portland cement concrete. Traditional classifications and methods of corrosion were widely used for the assessment of steel in concrete which may get employed to concrete which contains LC3 to recalibrate the range of polarization resistance for passitivity condition. For example, there is up to 79.5% and 146% respective flexural and compressive strengths. Moreover, they developed more advance electrical and thermo-mechanical performance with a substantial reduction in absorption of water of close to 400%. These advantages allow this research crucial to evaluate how these methods can be applied. Additionally, the research evaluates developed and more advanced cement preservation and repair techniques. The conclusion suggests concerted efforts by various stakeholders such as policy makers to enable low-carbon rates.