• Journal of the Korean Wood Science and Technology
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• v.45 no.6
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• pp.762-771
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• 2017

Predicting the amount and distribution of moisture content within wood allows calculating the various mechanical dynamics of the wood as well as determining the drying time. For boxed-heart wood with a large cross-section, since it is difficult to measure the moisture content of the interior, it is necessary to predict the moisture content distribution. This study predicted the moisture movement in boxed-heart red pine timber, during high temperature drying, by using the three-dimensional finite difference method for the efficient drying process. During drying for 72 h, the predicted and actual moisture content of the tested wood tended to decrease at a similar rate. In contrast, the actual moisture content at 196 and 240 h was lower than predicted because surface checking of the wood occurred from 72 h and excessive water emission was unexpectedly occurred from the checked and splitted surface.

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.1
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• pp.51-60
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• 2020

The purpose of this study is to determine the spatial and temporal resolutions that can represent land surface characteristics comprised of various land use using Landsat/AMSR2-based soil moisture data. We estimated the Landsat (30 m×30 m)-based soil moisture values using the soil moisture regression model. Then, the Landsat (30 m×30 m)-based soil moisture (reference values) were resampled to the relatively coarse resolutions from 1 km to 4 km, respectively. Comparing the reference values to the resampled soil moisture values, we confirmed that uncertainties were increased with the spatial resolutions of 2 km~4 km indicating that the spatial resolution of 1 km×1 km is required to represent the complicated land surface. Also, the AMSR2 soil moisture values have less uncertainties compared to SMAP data with the temporal resolution of 1~2 days. Thus, our findings can be useful for various areas such as agriculture, hydrology, forest, etc.

• Journal of Environmental Science International
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• v.3 no.2
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• pp.89-100
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• 1994

It is very important to assess accurately the terms which are included in the heat budget equation of soil surface because they are used in the UM and miso-scale circulation modeling as well as in the micrometeorological studies. Each terms in the heat budget equation change according to the soil moisture content. So, it is necessary to specify clearly the relations between soil moisture content and these terms. Special experiment with micrometeorological measurements was executed to study these relations at Environmental Research Center of Tsukuba University, Japan. The results are as follow: 1. The soil moisture contents of 1 cm and 4 cm depth are oscillated with one day Period in drying process and the amplitude of variation of 1 cm depth is greater than that of 4 cm. 2. Increase in soil moisture contents due to precipitation result in decrease of albedo with step function. 3. Sensible heat is in reverse proportion to the soil moisture content and latent heat is in direct proportion to it. Latent heat is more sensitive than sensible heat according to the soil moisture variation. Net long wave radiation have high correlation with soil moisture. 4. Comparing with the radiative term with the flux term in wetting process due to precipitation, the energy transfer of the aero and thermodynamic flux is greater than that of the radiative heat flux.

• Journal of the Korean Applied Science and Technology
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• v.36 no.1
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• pp.248-257
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• 2019

On this study, we have observed the change of the gel nail morphology as the time elapse and measured the surface roughness/volume, moisture content/purcutaneous moisture vaporizing amount of the nail surface before gel nail treatment and after gel nail removing of the 100%acetone remover, 5%acetone remover and 0%acetone remover and the avocado non acetone remover for the comparison of the effect on the nail surface and the degree of the removing of the gel nail of the removers as the acetone contents. The removing ability were the order of 100%acetone remover, avocado non acetone remover, 5%acetone remover and the 0%acetone remover. There were no statistical significance difference in the nail surface roughness comparision before and after gel nail removing in 5%acetone, 0%acetone and avocado non acetone, and there was no statistical significance difference in the nail surface volume comparision before and after gel nail removing in 0%acetone. We measured the moisture content of the nail surface and the purcutaneous moisture vaporizing amount before gel nail treatment and after gel nail removing, resulted that, the decrease of the moisture content of the nail surface after removing the gel nail is the minimun and the increase of the purcutaneous moisture vaporizing amount of the nail surface after removing the gel nail is the minimun at the case of 0%acetone. In conclusion, 5%acetone remover and 0%acetone remover is possible to use as the gel nail remover and they had revealed that there was the least harmful effect on the nail. We hope that this study is utilized to the development of the non acetone remover and the basic research of the nail beauty industry.

• Journal of the Korean Wood Science and Technology
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• v.48 no.4
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• pp.488-502
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• 2020

In this study, the moisture absorption and desorption properties presented by the Health-Friendly Housing Construction Standards of South Korea were compared using the wood of three tree species (Douglas-fir, Hinoki, Larch) and two types of wood-based materials(Plywood, WML Board^Ⓡ). The national standards for functional building materials present that the amounts of moisture absorption and desorption should be at least 65g/㎡ on average, respectively according to the test method under KS F 2611:2009. Therefore, in this study, the moisture absorption/desorption properties of materials with no treatment (Control), with punching, and with surface stain finishing and the moisture absorption/desorption property improvement effects of the treatments were compared and analyzed. According to the results of this study, it was evaluated that all five types of wood and wood-based materials tested did not satisfy the amount of moisture absorption/desorption of at least 65g/㎡, which is the performance standard for moisture absorption/desorption functional building materials, indicating that untreated wood and wood-based materials cannot be applied as functional finishing materials according to the Health-Friendly Housing Construction Standards. The surface stain finishing greatly reduced the moisture absorption and desorption rates of the materials, and the amounts of moisture absorbed and desorbed were also shown to decrease by at least two times on average. When the surfaces of the materials were punched with Ø4mm holes at intervals of 20 mm, the moisture absorption/desorption areas increased from 18% to 51%, and this increase was shown to be capable of increasing the amounts of moisture absorbed/desorbed by 29% on average at the minimum, and 81% on average at the maximum. The effects of punching were shown to be identical even in cases where the materials were stain finished. For the application of wood or wood-based materials as eco-friendly, health-friendly, and moisture absorption/desorption functional building materials hereafter, it is judged that new physical and chemical improvement studies should be conducted, and treatment methods should be developed.

• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.1
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• pp.57-70
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• 2017

In this study, we evaluated daily root zone soil moisture dynamics and agricultural drought using a near-surface soil moisture data assimilation scheme with Soil Moisture Active & Passive (SMAP, $3km{\times}3km$) soil moisture footprints under different hydro-climate conditions. Satellite-based LANDSAT and MODIS image footprints were converted to spatially-distributed soil moisture estimates based on the regression model, and the converted soil moisture distributions were used for assessing uncertainties and applicability of SMAP data at fields. In order to overcome drawbacks of the discontinuity of SMAP data at the spatio-temporal scales, the data assimilation was applied to SMAP for estimating daily soil moisture dynamics at the spatial domain. Then, daily soil moisture values were used to estimate weekly agricultural drought based on the Soil Moisture Deficit Index (SMDI). The Yongdam-dam and Soyan river-dam watersheds were selected for validating our proposed approach. As a results, the MODIS/SMAP soil moisture values were relatively overestimated compared to those of the TDR-based measurements and LANDSAT data. When we applied the data assimilation scheme to SMAP, uncertainties were highly reduced compared to the TDR measurements. The estimated daily root zone soil moisture dynamics and agricultural drought from SMAP showed the variability at the sptio-temporal scales indicating that soil moisture values are influenced by not only the precipitation, but also the land surface characteristics. These findings can be useful for establishing efficient water management plans in hydrology and agricultural drought.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.1172-1175
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• 2003

The characteristics and change of electrode surface about Gap type surge arrester for protect DC subway rail were investigated with moisture absorption. Compared that tested about DC/AC discharge commencement voltage, residual voltage, Impulse, square wave impulse for DC rail surge arrester about Gap type surge arrester of moisture absorption state. The AC discharge commencement voltage acted greatly effect of moisture absorption than the DC discharge commencement voltage test.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.11a
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• pp.117-120
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• 2009

It has been gradually increased with the use of resin based membrane forming agent for curing method, which plays a role in protecting moisture evaporation by forming resin membrane at the surface of concrete. In this paper, tests were carried out to examine moisture retention capability of cement mortar applying membrane forming agent. Dosages and types of the membrane forming agent were varied. It is found that sheet curing sealed with the surface of concrete closely has favorable moisture retention capability. However, the application of membrane forming curing method had superiority in moisture retention capability at early stage but at later age, its capability is deteriorated. Hence, further study regarding altering application method was necessary to secure enhanced moisture retention capability.

• Korean Journal of Food Science and Technology
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• v.53 no.1
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• pp.92-98
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• 2021

The effects of heat-moisture treatment (HMT) on rice flour (RF) have been investigated for possibility of texture modifier in protein-based foods matrix, tofu. The optimum condition for preparation of tofu with maximum textural parameters was investigated by using response surface methodology (RSM). Rice flour was subjected to moisture content (10-30%) and heating temperature (100-140℃). Based on the response surface and superimposed plots, the optimized conditions of hydrothermally treated rice flour was as followed: moisture content, 22%; temperature, 130℃, which showed lower swelling power as compared to native RF and became more stable during continuous heating and agitation than native one. Tofu, prepared with HMT-RF, showed a denser network structure than that with RF, thereby inducing an increase in textural parameters. From the above results, the addition of HMT-RF could preserve the quality of tofu and be useful for developing an acceptable protein-based food product.

• Food Science and Biotechnology
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• v.14 no.1
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• pp.28-31
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• 2005

To extract apple pectins, apple pomace (AP) was extruded under 14 different conditions of screw speed (250-350 rpm), feed rate of 30-40 kg/hr, and 20-30% moisture content using twin-screw extrusion. Response surface methodology (RSM), based on three variables by three-level factorial design, was employed to investigate effects of screw speed, feed rate, and moisture on dependent variables of extrudates, soluble dietary fiber (SDF), yield of anhydrogalacturonic acid ($Y_{AGA}$) representing pectin, and intrinsic viscosity ([${\eta}$]). Second order models were used to generate three-dimensional response surface for dependent variables, and their coefficients of determination ($R^2$) ranged from 0.96 to 0.99. Moisture content showed highest effect on solubilization of AP.