• Textile Coloration and Finishing
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• v.11 no.5
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• pp.30-37
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• 1999

The extracts drawn out from Artemisia princeps by water was concentrated. Using this concentrate the silk and the cotton fabrics were dyed, and they were measured with the K/S value, surface color and mordant quantity in order to evaluate the dyeability and the antimicrobial activity. The results are as follows; 1. The K/S value of the silk fabric was much higher than that of the cotton fabric. And the color yield of the dyed silk fabric was most efficient for the premordanting method. 2. The surface colors on the dyed fabric depended heavily upon mordants used or mordanting methods. For all cases, the value of the dyed fabric was generally dark. For the Cr-mordant among various mordants, the chroma produced clear and the color difference was distinct when using the Fe-mordant. 3. On the other hand the amount of absorbed mordant in the silk fabric was larger than that of the cotton fabric. And the Cu-mordant was most efficient. 4. The color fastness was significantly improved when mordants were added. Cr-mordant improved best in all of the dry cleaning, wet cleaning and perspiration fastness. Iron and abrasion fastness showed over 4-5 grade regardless of any mordant. And light fastness was best in Cu-mordant. 5. The Cu-mordant showed the greatest antimicrobial activity in both of mordant treat silk and cotton fabrics.

• Journal of the Korean Chemical Society
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• v.26 no.3
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• pp.135-141
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• 1982

The gamma radiolysis of C$O_2$, in the presence of organic additives, was studied at the total absorbed dose of 6.7 Mrad. Considerable quantity of CO was produced by adding these additives to $O_2$, though no CO was found without them. The maximum G(CO) values of 4.1 and 4.6 were obtained by addition of 0.5% methanol and 0.25% ethanol, respectively. The G(CO) values of 6.3 and 8.4 were noted by the addition of 1% acetaldehyde and 1% formaldehyde, respectively. The maximum CO concentration of 0.65% was obtained by the addition of 1% acetaldehyde at the dose of 40 Mrad.

• International Journal of Automotive Technology
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• v.8 no.1
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• pp.93-102
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• 2007

The frontal crash optimization of an engine room member using the response surface method was studied. The engine room member is composed of the front side member and the sub-frame. The thicknesses of the panels on the front side member and the sub-frame were selected as the design variables. The purpose of the optimization was to reduce the weight of the structure, under the constraint that the objective quantity of crash energy is absorbed. The response surface method was used to approximate the crash behavior in mathematical form for optimization procedure. To research the effect of the regression method, two different methodologies were used in constructing the response surface model, the least square method and the moving least square method. The optimum with the two methods was verified by the simulation result. The precision of the surrogate model affected the optimal design. The moving least square method showed better approximation than the least square method. In addition to the deterministic optimization, the reliability-based design optimization using the response surface method was executed to examine the effect of uncertainties in design variables. The requirement for reliability made the optimal structure be heavier than the result of the deterministic optimization. Compared with the deterministic optimum, the optimal design using the reliability-based design optimization showed higher crash energy absorption and little probability of failure in achieving the objective.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.05a
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• pp.23-26
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• 2006

The study about the concrete to use recently a light weight aggregate, processed actively. And concrete pumping with a high pressure pump has been popularized, the mechanical development, such as high pressure pumps or pipes, is progressing rapidly. Concrete placing by pumping has the advantage of the reduction of the construction period with workability, easiness of work and the increase of placing, but the quality variation of concrete is caused by pumping is seldom considered, including the increase of the pipe length by high-rising and large-sizing, there by the loss of the unit quantity of water, with pumpability or workability deteriorated. In this research, we will compare and analyze before pumping and after pumping samples of ready-mixed light weight concrete. The result of study as follow. The case of a light weight concrete which the low slump is more decrement compared with high slump light weight concrete in after pumping samples. After pumping the water by pressure of a pump was absorbed to the aggregate inside, and it showed an increase of compression strength about $5{\sim}20%$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.71-74
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• 2002

Currently small and accurate dosimeters are on the rise. In this study, the feasibility and energy dependency of the electret dosimeter that made of PET (polyethylene terephtalate) were observed by irradiating 4, 6, 15 MV photon beams from the clinical linear accelerator to develop a dosimeter for the clinical field. $10{\times}10cm$ field size of the photon beams were irradiated to the electret dosimeter where the 2.5 cm depth in the polystylene phantom from 100 cm SSD, while 300 DCV was applied to the electret dosimeter. The result showed that the absorbed dose was proportional to the charge linearly, and the volume of a dosimeter could be reduced and the signals were high enough. According to this study, it was found that the polymer electret detector could be produced as a large quantity with a small cost and showed the feasibility of a realtime measurement.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.729-732
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• 2008

Recently the attention against the indoor air quality that could affect health and comfort of building becomes intensively, the efforts for a problem solving is advanced with many sidedness. The research which it mixes the activated carbon and the functional catalyst materials that will be able to dissolve foul air absorbed by activated carbon in concrete with application technique of existing differently examined the basic physical properties and the removal ratio of formaldehyde so that it analyzed the effect of air purge. The test results in addition quantity increase of the activated carbon the slump showed the tendency which it decreased and the compressive strength appeared with no much difference. The test result removal ratio of formaldehyde was measured until the maximum 80%.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.19-22
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• 2011

For underground structures that are exposed to environmental conditions, the declination of the durability of concrete occurs easily because of leakages from high hydraulic pressure and the frequent contact of water due to environmental factors. Therefore this study is to confirm that the leakage reduction of natural inorgnic powder compound applying subsurface structural weak part and make the performance improvement of concrete as an objective. The test was done by making the rebar, flat tie, nail and film infiltration and each of its water tank and cylindrical test body then after pouring water to each of the test body, the test observe the change of the water tank surface absorbed condition and leakage of each specimen with respect to time. As a conclusion, the test was observed that this water proofing admixture has better watertightness from the beginning of the setting time(when it hardens), the ettringite and the thaumasite generates a large quantity of hydration products that controls the formation in a large opening and the CSH produced by pozzolan reaction makes a dent at this opening.

• Korean Journal of Metals and Materials
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• v.49 no.12
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• pp.945-949
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• 2011

The cycling characteristics of $MgH_2$ made by hydriding chemical vapor deposition method have been investigated. The particle size of $MgH_2$ made by HCVD was about $1{\mu}m$. The cycling experiment was performed by measuring hydrogen quantity absorbed at 673 K and under 35 atm of hydrogen pressure for 30 min. Up to 3 cycles the hydrogen storage capacity increased, but from 4 to 6 cycles the hydrogen storage capacity decreased rapidly. During this cycling test the particle size increased gradually from $1{\mu}m$ to $6{\mu}m$. This increase was due to sintering by the high reaction temperature and the heat of reaction during hydrogen absorption. From 7 to 30 cycles, the hydrogen storage capacity was maintained at 5.8 wt%. Even after 30 cycles, the plateau pressure was constant.

• Metals and materials international
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• v.24 no.6
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• pp.1403-1411
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• 2018

Graphene (multilayer graphene) was chosen as an additive to improve the hydrogen uptake and release properties of magnesium (Mg). Five weight percent of graphene was added to pre-milled Mg by milling in hydrogen (reaction-involving milling). The hydrogen uptake and release properties of the graphene-added Mg were investigated. The activation of Mg-5graphene, which was prepared by adding 5 wt% graphene to Mg pre-milled for 24 h, was completed after the second cycle (cycle number, CN=2). Mg-5graphene had a high effective hydrogen-storage capacity (the quantity of hydrogen absorbed for 60 min) of 6.21 wt% at CN=3 at 593 K in 12 bar $H_2$. At CN=1, Mg-5graphene released 0.46 wt% hydrogen for 10 min and 4.99 wt% hydrogen for 60 min. Milling in hydrogen is believed to create defects (leading to facilitation of nucleation), produce cracks and clean surfaces (leading to increase in reactivity), and decrease particle size (leading to diminution of diffusion distances or increasing the flux of diffusing hydrogen atoms). The added graphene is believed to have helped the sample have higher hydrogen uptake and release rates, weakly but partly, by dispersing heat rapidly.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.4
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• pp.264-269
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• 2016

The present study was conducted to establish the optimal fertilization type and method for no-tillage during the first year of No-tillage (NT) and Conventional-tillage (CT) practices for soybean, using different types of fertilizers. In this experiment, the culm length and stalk diameter showed a greater response to fertilization with surface irrigation than to conventional fertilization. The fastest flowering period (July 28) occurred using chemical fertilization applied via subsurface irrigation. Comparing maturation based on growth characteristics and flowering date revealed that fertilization with subsurface irrigation was more effective for the growth of crops than other methods. Regarding yield, there was no significant difference between livestock and chemical fertilizers in subsurface irrigation, but there were significant differences between these fertilizers when using conventional fertilization methods. Based on the results, livestock fertilizer with subsurface irrigation effectively enhanced crop quantity. Nitrogen absorption of plants using subsurface irrigation was more effective than that using conventional fertilization. Regarding phosphorus absorption of plants, chemical fertilizers showed higher absorption than did livestock fertilizers for both subsurface irrigation and conventional fertilization. Unlike nitrogen, phosphorus was highly absorbed using conventional fertilization. Absorption of phosphorus and potassium were similar but phosphorus was not absorbed using livestock fertilizers applied either using subsurface irrigation or with conventional fertilization.