• Journal of Biosystems Engineering
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• v.30 no.2 s.109
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• pp.95-101
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• 2005

Adsorption and desorption experiments were carried out on rough rice and brown rice (Nampyung) at 5, 15, 25, 35, $45^{\circ}C$ for moisture contents between 8.7 and $25\%$ (db). The method employed was to measure the equilibrium relative humidity (ERH) of air in contact with the grain under static conditions, using an electronic hygrometer The effects of temperature and moisture contents were investigated, and the measured values were fitted to the modified Henderson, the modified Chung-Pfost, the modified Halsey and the modified Oswin model. The ERHs of rough rice and brown rice decreased with an decrease in moisture content and temperature, and the effects of temperature was no significant at moisture content of $25\%$ (db). Equilibrium moisture content (EMC) of brown rice was higher than rough rice at same temperature and relative humidity. Desorption EMC is higher than the adsorption, but there is no significant difference between desorption and adsorption EMC in moisture content near $25\%$ (db) at rough rice and near 9, 21 and $25\%$ (db) at brown rice. The modified Oswin model was the best in describing the adsorption EMC and the modified Chung-Pfost model was the best in describing the adsorption ERH of rough rice. The modified Oswin model was the best in describing the adsorption EMC/ERH of brown rice. The modified Chung-Pfost model was the best in describing the desorption EMC/ERH of rough rice and brown rice.

• Journal of Ecology and Environment
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• v.41 no.10
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• pp.281-289
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• 2017

Background: In this study, the growth and reproductive response of seedlings, grown in plastic pots with sand, to moisture and nutrients were analyzed in order to study the environmental conditions required to create an alternative habitat for Epilobium hirsutum L., an endangered plant. Results: Vegetative and reproductive growths of Epilobium hirsutum L. are accelerated with increase in moisture and organic matter content in the soil. Among vegetative organs, the number of runners related to asexual reproduction was the highest when the moisture content was over 25% and nutrient content between 7 and 14% in the soil. But the number of flowers related to flowering responses, among reproductive organs, was the highest when the moisture content was maintained at 75% and when nutrient content was 21% in the soil. The number of seeds, related to sexual reproduction, was the highest when the moisture content was over 25% and nutrient content between 14 and 21%. Conclusions: The study results show that a place with high moisture and nutrient content in the soil is advantageous to asexual and sexual reproduction of Epilobium hirsutum L. Therefore, we must serve periodically nutrient and seeds to sustain population in in situ conservation. Furthermore, it is advisable to create in riverside where abundant nutrient content have, making alternative habitat of Epilobium hirsutum L. Also, we must find species that have high contribution degree index through vegetation survey.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.2
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• pp.101-104
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• 1998

This study was conducted to establish a rapid analysis method for determining protein and moisture contents of pea. Ninety and eighty pea (Pisum sativum L.) lines were analyzed to determine protein and moisture contents, respectively using near-infrared reflectance spectroscopy. Simple correlations (${\gamma}$) of protein content in a ground sample and an intact grain sample by an automatic regression method were 0.978 and 0.910, respectively. Simple correlations by partial least square regression/principal component analysis (PLS/PCA) methods were 0.982 and 0.925, respectively. Standard error of performance (SEP) in protein content was the lowest value, 0.446 in ground sample by PLS/PCA methods. Simple correlation of moisture content was the highest at 0.871 in ground samples. when using a standard regression method. Accuracy for the moisture content was slightly lower than for protein content. It was concluded that the NIRS method would be applicable only for rapid determination of protein content in pea.

• Magazine of the Korean Society of Agricultural Engineers
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• v.16 no.3
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• pp.3539-3542
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• 1974

Maximum density and optimum moisture content of a soil may be one of the very important properties to be specified in the design of earth structures and their works. However, the determination of these soil properties may not be done without the necessary equipment and time-consuming field tests. This study was conducted to develop an easier method by determing the relations between the natural moisture content and optimum moisture content and between maximum density and optimum moisture content so determined. These velations are remarkably defferent according to the areas where the samples were taken, and thus analysis of the experimental results are shown by regions as follows: Eastern Districs:{{{{Tdmax= { 1} over {0.0090Wopt+0.417 } ( delta = +- 0.042, gamma =0.92) Wopt=0.251WN+8.5( delta = +- 2.41%, gamma =0.87) }}}} Southern Districts: {{{{Tdmax= { 1} over {0.0088Wopt+0.412 } (delta = +- 0.083, gamma =0.89) Wopt=0.332WN+8.42(delta = +- 3.41%, gamma =0.84)}}}}Central Districtsl1): {{{{Tdmax= { 1} over {0.0112Wopt+0.383} ( delta = +- 0.052, gamma =0.97) Wopt=0.758WN+2.606( delta = +- 4.72%, gamma =0.79)}}}}($\delta$:Standard Deviation, ${\gamma}$:Correlation Coefficient)

• Journal of the Korean Wood Science and Technology
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• v.25 no.2
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• pp.67-74
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• 1997

A relationship between drying resistance and moisture content was found for 24, 27 and 30mm thick boards, and 45, 51 and 57mm thick dimensions of Japanese larch. Dahurian larch and radiata pine in order to modify the kiln schedule by using time schedules. The amount of drying resistance for Dahurian larch lumber was the highest, and radiata pine lumber was the lowest, on the basis of the same moisture content range. Drying resistance increased curvilinearly as moisture content decreased, and was higher for thicker lumber than for thinner lumber, at a given moisture content. Combined drying resistance for the three board thicknesses and the three dimension thicknesses showed a comparatively strong for radiata pine and a Japanese larch, while a weak correlation for Dahurian larch as a function of two independent variables, thickness and moisture content of lumber, respectively.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.1
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• pp.107-122
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• 2015

The purpose of this study is to analyze the structural stability of pavement due to water infiltration at the road with infiltration trench as using the FEM(finite element analysis). Five cases for FEM is divided considering the amount of rainfall and rain duration time. The results of FEM show that the more rainfall in a short period time is faster the change of moisture content. Also, it is the proportional relationship between and changing area of moisture content of more than 40% due to rainfall. Case 3 and 4 are necessary to check the installation of infiltration trench because of moisture content of more than 40%, recovery time of initial moisture content, and changing area of more than 40%. Case 1,2, and 5 have no a significant effect on road pavement structure due to lower moisture content and shorter duration time of higher moisture content.

• Magazine of the Korean Society of Agricultural Engineers
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• v.22 no.3
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• pp.60-74
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• 1980

Soil-cement mixtures involve problems in it's durability in grain size distribution and mineral composition of the used soils as well as in cement content, compaction energy, molding water content, and curing. As an attempt to solve the problems associated with durability of weathered granite soil with cement treated was investigated by conducting tests such as unconfined compression test, it's moisture, immers, wet-dry and freeze-thaw curing, mesurement of loss of weight with wet-dry and freeze-thaw by KS F criteria and CBR test with moisture curing on the five soil samples different in weathering and mineral composition. The experimental results are summarized as follows; The unconfined compressive strength was higher in moisture curing rather than in the immers and wet-dry, while it was lowest in freeze-thaw. Decreasing ratio of unconfined compressive strength in soil-cement mixtures were lowest in optimum moisture content or in the dry side rather than optimum moisture content with freeze-thaw. The highly significant ceofficient was obtained between the cement content and loss of weight with freeze-thaw and wet-dry. It was possible to obtain the durability of soil-cement mixtures, as the materials of base for roads, containing above 4 % of cement content, above 3Okg/cm$_2$ of unconfined compressive trength with seven days moisture curing or 12 cycle of freeze-thaw after it, above 100% of relative unconfined compressive strength, 80% of index of resistance, below 14% of loss of weight with 12 cycle of wet-dry and above 1. 80g/cm$_2$ of dry density.

• Journal of Biosystems Engineering
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• v.3 no.2
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• pp.62-68
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• 1978

Equilibrium moisture content of rough rice is an important factor because it has a close relationship to storage and drying problems. Determination of the EMC for 10 different varieties of rough rice were made in atmospheres of various constant humidities at three different constant temperatures. In addition , some physical properties were also measured for two different levels of moisture content of the samples. The results may be summarized as follows ; 1. Several physical properties of ten different varieties of rough were measured. Significant difference of the properties was appeared between the varieties in which the difference was pronounced in the dimensions of the varieties. Also, all the dimensions were increased as the moisture content of the rough rice was increased from 14 % to 16%. 2. Significant difference of the equilibrium moisture content was also appeared between some of the varieties in which the equilibrium moisture content of Josaengtongil and Minehikari was 24.26% while that of the others was in the range between 18 to 19% at the conditions of relative humidity of 84% and temperature of 47℃ , respectively. Similar pattern was also observed in other conditions. 3. The values of the constant of Henderson's equation were calculated from the data obtained but they are believed to be useful until more precise and complete data are obtained. There was a good agreement between the calculated and experimental results.

• Journal of the Korean Wood Science and Technology
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• v.48 no.1
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• pp.12-21
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• 2020

For quantitative evaluation of wooden structures, the mechanical performance of members has undergone outdoor exposure tests. A year-long monitoring was conducted using an SPF species. Test groups were divided into twelve (each month) to measure the moisture content, density and ultimate load. Starting from May when moisture content of the test group was at the lowest, simple failure modes were observed more frequently during the first half of the experiment, whereas complex failure modes took over during the second half. Starting from June when moisture content of the test group was the highest, ultimate load decreased by 30% in the second half compared to the first half. A multiple regression analysis confirmed that moisture content of the test group was the variable with most effect on ultimate load of various outdoor variables, and an estimation equation of a simple regression analysis revealed that moisture content and ultimate load formed an inversely proportionate relationship. It is thought that correlational relationships of variables other than moisture content could be applied with the increase in added data amount by longer periods of outdoor exposure tests.

• The Korean Journal of Food And Nutrition
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• v.35 no.1
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• pp.62-73
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• 2022

Omija seed oil was extracted from Omija seeds, a by-product of Omija, using an eco-friendly pressed extraction method. Physicochemical properties and antioxidant activities of 12 extracts using different combinations of seed moisture content (5, 7.5, and 10%) and extraction temperature (25, 49, 75, and 100℃) were then investigated. The highest extraction yield was 31.33% at moisture of 5% and temperature of 75℃. The lowest acid value was 4.18±0.25 at moisture of 5% and temperature of 49℃or moisture of 7.5% and temperature of 25℃. Peroxide value, iodine value, and saponification value were the lowest at 0.64±0.56 meq/kg, 159.38± 6.03, and 57.60±9.40, respectively, at moisture of 5% and temperature of 25℃. The content of total polyphenolics was the highest at 4,413±125 mg TAE/100 g when the moisture content was 10% and the extraction temperature was 25℃. DPPH radical scavenging activities of oil extracts at 20~100 mg/mL were 28.68±7.30~87.65±2.20%. The maximum antioxidant activity and IC₅₀ were 87.65±2.20% and <20 mg/mL, respectively, for extract obtained at moisture of 10% and temperature at 100℃. As a result, the extraction yield, acid value, peroxide value, iodine value, saponification value, and so on were excellent at moisture content of 5% and extraction temperature of 25℃ or 49℃. However, the content of total polyphenolic compounds and antioxidant activity were the highest at moisture of 10% and extraction temperature of 100℃. In conclusion, extracting Omija seed oil from Omija seeds, a by-product of Omija, is effective with a pressed extraction method.