• Fire Science and Engineering
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• v.23 no.5
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• pp.17-23
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• 2009

Moisture evaporates, when concrete is exposed to fire, not only at concrete surface but also at inside the concrete to adjust the equilibrium and transfer properties of moisture. The equilibrium properties of moisture are described by means of water vapor sorption isotherms, which illustrate the hysteretical behavior of materials. In this paper, the prediction method of the moisture distribution inside the concrete members at fire is presented. Finite element method is employed to facilitate the moisture diffusion analysis for any position of member. And the moisture diffusivity model of high strength concrete by high temperature is proposed. To demonstrate the validity of this numerical procedure, the prediction by the proposed algorithm is compared with the test result of other researcher. The proposed algorithm shows a good agreement with the experimental results including the vaporization effect inside the concrete.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.1033-1037
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• 1997

The occurrence of mold growth due to moisture migration in a composite chocolate product filled with marshmallow during storage was investigated. The correlation between water activities and water contents of dark chocolate coating and filling marshmallow at $25^{\circ}C$ was well applied to Kuhn's equation. The marshmallow was found to be more hydrogroscopic than the chocolate. Since the moisture transferred from marshmallow to chocolate, the water activity of marshmallow decreased from 0.88 to 0.80 and that of chocolate increased from 0.22 to 0.76 at $25^{\circ}C$ for 30 days. This water activity, 0.76, can allow mold growth. A mold was isolated on the surface of a composite chocolate product at $25^{\circ}C$after 3 months and then was identified as Aspergillus repens. Growth experiments at varied water activities with A. repens were performed. When the water activity in a chocolate solid medium increased from 0.73 to 0.93, the occurrence time of mold growth decreased from 62 to 15 days. These results suggested that the occurrence of mold growth was due to the increased water activity of the chocolate resulting from the moisture transfer from filling marshmallow dark to chocolate coating.

• Korean Journal of Pharmacognosy
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• v.42 no.2
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• pp.182-186
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• 2011

Houttuynia cordata Thunb.[H.cordata]belonging to Saururaceae, is a wild medicinal herb of perennial plants, and grows well in a place with a lot of shade and moisture. The medical action of H.cordata is reported to have an antitumer effect, toxicity-suppressive effect, antifungal effect, diuretic effect, and antioxidative action, but its effect hasn't been reported on cardiovascular diseases, such as ateriosclerosis and hypertension yet. This study intended to confirm the effect of the water extract of H.cordata on the migration and proliferation of rat aortic smooth muscle cells. Such results show that the water extract of H.cordata suppresses the migration and proliferation of rat aortic smooth muscle cells. It is believed that a useful clue will be offered later to the prevention of cardiovascular diseases such as ateriosclerosis and hypertension, and the development of their medicines on the basis of the fact.

• Journal of the Korean Society of Tobacco Science
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• v.28 no.1
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• pp.31-35
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• 2006

In this study, the effects of the relative humidity and storage time of blended tobaccos at total blending silo on cut tobacco equilibrium moisture contents, leaf moisture contents and migration of casing materials of tobacco types were investigated. To maintain the cutting moisture content(21 $\pm$ 1 %), it is necessary to keep 75 % relative humidity at 28 $^{\circ}C$ at total blending silo. The moisture content of reconstituted tobacco sheet was changed from $13{\sim}14$ % to $19{\sim}21$ % within 2 h after preblending. The contents of glycerin and fructose of tobacco types followed by storage time after preblending were not changed significantly. From these results, it is suggested that 2 h storage time after preblending was sufficient to maintain physical properties of cut tobaccos and tobacco taste and fragrance.

• Journal of Korea Soil Environment Society
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• v.4 no.2
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• pp.103-111
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• 1999

This study is on the mathematical modeling and its verification of the retardation phenomenon of gas migration in an unsaturated zone of very little moisture content The adsorption of VOCs onto the surface of the dry medium was taken into account, which has not been usually considered in the conventional models. The trichloroethylene(TCE) gas migration predicted from the mathematical model developed in this study fits the experimental results obtained from a dry glass-bead column and a dry silica sand column very well The model developed in this study gave much better prediction than did a coventional model.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.3
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• pp.425-430
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• 2011

This study evaluated the effect of extraction conditions of yam (Dioscorea aimadoimo) on antioxidant, moisturizing, collagenase activity, proliferation, and migration. Yam has been recognized as a healthy food due to its various biological activities, such as anti-obesity, anti-constipation, anti-mutagenic activities, as well as its ability to decrease blood glucose and cholesterol levels. Electron donating ability of high temperature ethanol extract of Dioscorea aimadoimo (HDA) had shown 70.6% at 400 mg/ml, and low temperature ethanol extract of Dioscorea aimadoimo (LDA) had shown 40% at 400 mg/ml. SOD-like activities of LDA and HDA were 23% and 34% at 400 mg/ml respectively. LDA significantly reduced the activity of collagenase in a dose-dependent manner, which was higher than HDA. The water contents in LDA-treated skin and HDA-treated skin were increased by 45.63% and 38.65% than the placebo cream respectively. The cellular proliferation of human dermal fibroblast neonatal (HDFn) was evaluated by MTT and cell migration assay. Compared to control, the cell proliferation was elevated to 109.7% and 114% by the treatment of LDA and HDA respectively at the concentration of 200 mg/ml. In addition, LDA and HDA were induced cell migration in HDFn. Our study suggests that LDA and HDA should be a very useful cosmetic ingredient, as anti-aging and skin moisturizer.

• Fashion & Textile Research Journal
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• v.25 no.1
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• pp.119-126
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• 2023

This study aimed to determine the effects of relative humidity and fiber properties on the moisture permeability of multilayer systems by measuring water vapor transmission in the overlapping condition of various fabrics. The results confirmed that the property of the fabric in contact with the humid environment affects the moisture permeability. If the layer facing the humid environment is hydrophobic and the layer facing the dry environment is superhydrophobic, water vapor transmission increases by up to 17.8% compared to the opposite conditions. Comparing the correction values of the water vapor transmission reflecting the thickness of the specimen under the multilayer condition showed that permeability was higher when the hydrophilic or hydrophobic layer was facing the humid environment. The opposite was true from the "push-pull" effect of absorption mechanism. In the case of moisture permeability, the more hydrophilic the surface facing the humid environment, the more permeable that water vapor diffuses and passes through. It was concluded that the "pull-push" effect, in which water vapor diffuses widely through the hydrophilic facing a humid environment and then passes through the hydrophobic layer, contributes to the improvement of permeability. Permeability differed according to the multilayer overlapping condition. When the relative humidity was high, the "pull-push" effect was insignificant. This is caused by water droplets absorption after the partial migration of water due to condensation. These results suggest that the overlapping conditions and properties of fabrics should vary depending on heavy sweating or not.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.10 no.1
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• pp.7-14
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• 2004

Migration behavior of selected solvents and food samples showed differences of the chemical structures and polarities, the food samples which have similar polar expresses more higher affinity than different polar degrees. Water which is polar has a highest partitioning coefficient values on polar isopropanol, and oil which is nonpolar has highest partitioning value on non-polar toluene. The increasing order of partitioning values was accord with increasing water contents in food samples. It is showed that the wheat flour with 13.2% moisture content has the highest partitioning coefficient values on the isopropanol with -OH. Kp value of sugar showed remarkable lower partitioning coefficient values than other food samples due to high degree crystallinity. This phenomenon can be predictable with ${\delta}$ values, because order of partitioning coefficient values which comes out through the experiment and the sequence of Hildebrand solubility parameter value difference between food sample and printing ink solvent correspond almost. This Hildebrand solubility parameter value can be easily applied to the food package industry because the effect of food-safety can be considered without passing through complicated steps by using this method.

• Magazine of the Korean Society of Agricultural Engineers
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• v.35 no.4
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• pp.47-54
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• 1993

A series of laboratory tests was performed with soil-columns which were compacted with sands and different amount of silt collected from the mid-stream of Gumgang, Korea. A known degree of concentration of PCP(Pentachlorophenol) was poured into the soil-columns and concentration of PCP was monitored and analyzed with time and depth. The results of the study are summarized as follows : 1. PCP was transported into soil along with the movement of moisture under gravitational force. The amount of PCP transported through soil or absorbed by soil varied with soil types. 2. The great amount of PCP was remained at 4~8cm section for the specimen No.2 and at 0~4cm section for the specimen Nos. 3 and 4. Based upon this result it is said that the amount of silt between 30 and 40% may be a threshold value for PCP transported through soil. 3. The amount of PCP remained in the specimen Nos. 2, 3 and 4 is greater than that in the specimen No.1 due to high specific surface of silt and high attraction force between PCP and silt particles in the specimen Nos. 2, 3 and 4. 4. It is said that groundwater under highly permeable soil layer such as specimen No.1 is easily polluted by PCP. That is because the PCP is basically migrated with water under the gravitational force.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.3-17
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• 2007

This paper provides an introduction to life-span simulation and numerical approach to support the performance design processes of reinforced concrete structures. An integrated computational system is proposed for life-span simulation of reinforced concrete. Conservation of moisture, carbon dioxide, oxygen, chloride, calcium and momentum is solved with hydration, carbonation, corrosion, ion dissolution. damage evolution and their thermodynamic/mechanical equilibrium. Coupled analysis of mass transport and damage mechanics associated with steel corrosion is presented for structural performance assessment of reinforced concrete. Multi-scale modeling of micro-pore formation and transport phenomena of moisture and ions are mutually linked for predicting the corrosion of reinforcement and volumetric changes. The interaction of crack propagation with corroded gel migration can also be simulated. Two finite element codes. multi-chemo physical simulation code (DuCOM) and nonlinear dynamic code of structural reinforced concrete (COM3) were combined together to form the integrated simulation system. This computational system was verified by the laboratory scale and large scale experiments of damaged reinforced concrete members under static loads, and has been applied to safety and serviceability assessment of existing structures. Based on the damage details predicted by the nonlinear finite element analytical system, the life-span-cost of RC structures including the original construction costs and the repairing costs for possible damage during the service life can be evaluated for design purpose.