• Korean journal of applied entomology
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• v.3
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• pp.27-30
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• 1964

The effects of the rice weevils(Sitophilus oryzae L.) on naked barley and wheat were studied in connection with the moisture contents and the molds in the grain under the controlled conditions; R.H. $75\%,\; 28^{\circ}C.$ 1. The moisture contents of control grain were decreased $2.07\%$ for naked barley and $1.29\%$ in wheat in four weeks. 2. The moisture contents of naked barley which had been infested with 100 weevils were decreased $0.29\%$ and were increased $0.79\% in the berley infested with 200 weevils at t beginning. In wheat, the moisture contents were decreased by$0.84\%\; and\; 0.13\%$ in respective experimental lots. 3. The moisture contents of grains have close relation with the population densities of the weevils in the grain. 4. The pattern of the change in the moisture content of grain have close relation with the population densities of the weevils in the grain. 5. The number of the mold colonies in the grain increased exponentially with the increase in the population densities of weevils in the grain. 6. The species of the mold found were A. restrictus and A. versicolor, which were the most abundant, and A. candidus was also found, but Ins common.

• Journal of the Korean Society of Combustion
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• v.14 no.3
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• pp.16-23
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• 2009

It is strongly desired for coal-fired power plants to utilize not only low-rank coals with high moisture contents, but also lowering cost with diversifying fuel sources. In this study, combustion characteristics of low rank coal with high moisture, and standard pulverized coals are experimentally investigated using TGA (Thermogravimetric Analysis) and DTF (drop tube furnace). The coals tested are three kinds of coal with moisture content ranging from 8.32 to 26.82%. The results show that under the air combustion condition, the burn-out time at TGA rises as moisture content increases, and standard pulverized coal with 8.32% moisture content showed the lowest activation energy of 55.73 kJ/mol. In case of the high amount of moisture, the combustion efficiency decreases due to evaporation heat loss, and unburned carbon in ash produced at combustion process in DTF increased. Aslo, initial deformation temperature of slag attached in alumina tube of DTF decreased with lowering the crytallinity of anorthite and augite. To improve the combustion reactivity and efficiency, it is effective to upgrade through drying the high moisture coal to moisture level (less than 10%) of standard pulverized coal.

• Journal of the Korean Society of Tobacco Science
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• v.26 no.1
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• pp.43-49
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• 2004

This study was carried out to investigate moisture sorption and desorption characteristics followed by tobacco type. Experiments were performed at various temperature(5, 15, 25, 40 $^{\circ}C$) and relative humidity range (11～84 %) controlled by saturated salt solution. Regression equation was obtained to predict equilibrium moisture according to various relative humidity, temperature and tobacco types. The obtained regression equation showed high $R^2$(above 0.95) and predicted accurate equilibrium moisture. Equilibrium moisture contents declines in the following order when a relative humidity is 50 % or above: expanded stem, flue-cured, expanded tobacco, reconstituted tobacco, USA flue-cured, orient, burley. To maintain 13 % moisture of each tobacco type in the range of 5～40 $^{\circ}C$ it is recommendable to control relative humidity 49～56 % for expanded stem, 50～57 % for flue-cured, 54～61 % for USA flue-cured, 56～60 % for reconstituted tobacco, 57～62 % for expanded tobacco, 58～64 % for orient and 58～65 % for burley, respectively. It means that the relative humidity of each tobacco type should be differently controlled to maintain the same moisture under the same temperature. In the range of 5～25 $^{\circ}C$, the lower temperature showed the higher equilibrium moisture content.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.1
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• pp.329-336
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• 2013

The infrastructure of flexible pavement is composed of aggregate subbase, anti-frost layer, and subgrade. In particular, the subgrade performance is affected by climates such as frost action and precipitation. The method of TDR(Time Domain Reflectometry) sensors to measure moisture contents in subgrade layer has been used in the research. Due to the TDR method using dielectric permitivity of soil and water, the sensors can be affected by the low subgrade temperatures. The air temperatures frequently drops below $-20^{\circ}C$ in the winter in Korea. As a result, it is necessary to estimate the accuracy of the TDR moisture sensors in the range of below zero temperatures. In this study, the subgrade temperatures of lower than $-2^{\circ}C$ were extended to evaluate temperature sensitivity of the TDR moisture sensors. The test results revealed that the moisture contents around the sensors were reduced while those of the upper part of specimen showed a tendency to increase as the specimen surface temperature drops below zero under the volumetric moisture contents(VMC) of 20% and 30%. However, the impact of temperature on the function of the sensor at lower water contents was found to be negligible if any.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1407-1414
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• 2014

Physicochemical properties of rice-based expanded snacks extruded with rice flour, high amylose starch, and isolated soy protein were investigated using a twin-screw extruder. The ingredients were extruded at various feed moisture contents (19~23%) and screw speeds (200~400 rpm) at a constant feed rate (43.4 kg/hr). Bulk density and apparent density of rice snacks were 0.06~0.21, and 0.55~0.65 respectively. Bulk density, apparent density, water absorption index, and breaking strength of rice snacks increased with increasing feed moisture content and decreasing screw speed. However, expansion and water solubility index of rice snacks increased with decreasing feed moisture content and increasing screw speed. Hunter's color L values of rice snacks was lower with increasing screw speed at feed moisture contents of 19% and 21%, but was not significantly different from a feed moisture content of 23%. On the other hand, a and b values of rice snacks were higher with increasing screw speed a feed moisture content of 19%. X-ray diffraction intensity of rice snacks decreased with decreasing feed moisture content and increasing screw speed. X-ray diffraction of rice snacks was V-type at feed moisture contents of 19% and 21% and screw speeds of 300, and 400 rpm. In the microstructure of the cross section of rice snacks, air cells in rice snacks were not well formed, and cell walls were thicker with increasing feed moisture content and decreasing screw speed.

• Korean Journal of Food Science and Technology
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• v.19 no.3
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• pp.206-211
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• 1987

In an attempt to improve the quality stability of dried layer (Porphyra yezoensis Ueda), during longterm storage and distribution, a 6 months storage trial at different temperature and packaging condition was conducted. Dried layer samples were prepared by conventional procedure with different washing condition and $5^{\circ}C$ and $30^{\circ}C$ were employed as storage temperature. The moisture sorption isotherm was drawn at $5^{\circ}C$ and $25^{\circ}C$ and BET equation was prepared from the moisture sorption isotherm. The monolayer moisture contents of dried layer were 7.4% at $5^{\circ}C$ and 6.4% at $25^{\circ}C$, respectively. It was also found that the changes in comprehensive quality of dried layer during storage was much less at low temperature and the degree of washing before drying process as far as its moisture contents are lower than monolayer moisture contents. With regard to the packing methods, vaccum packing was superior to air containing packaging for the maintainance of quality during storage.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.4A
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• pp.373-384
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• 2009

For the first step on the quantitative evaluation of shrinkage reduction and differential shrinkage analysis of lightweight aggregate concrete, this study sets the moisture transport model of concrete by pre-absorbed water of porous lightweight aggregates and measured effective moisture diffusion coefficient, moisture capacity, degree of humidity supply and degree of humidity consumption by water binder ratio and aggregate type. The effective moisture diffusion coefficient in steady state caused by humidity difference between inside and outside of concrete had low value as low water-binder ratio. And in case of same water-binder ratio, effective moisture diffusion of mixtures used normal aggregates were lower than those used lightweight aggregates. To determine moisture store capability of concrete - moisture capacity, moisture contents were measured in 9 humidity conditions. As a result moisture contents of mixtures used lightweight aggregates was higher than mixtures used normal aggregates in all humidity conditions. This study measured lightweight aggregates' degree of humidity supply that applicable to normal atmospheric environment (above RH 50%) and made it quantitatively. Also amount of moisture release was set as a exponential function that represents a clear trend proportion to time and inverse proportion to humidity of the surroundings. As the result of measurement about degree of moisture consumption inside concrete following the internal consumption caused by cement hydration self-drying, it was showed that rapid decrease of humidity, around 10%, at early ages (7~10 days) when water-binder ratio is 0.3 and slow decrease around 5% and 1% when water-binder ratio is 0.4 and 0.5.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.838-843
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• 1997

The effects of the addition of apricot juice on Haengbyung qualities were evaluated. The reducing sugar contents, degree of gelatinization, moisture contents, color L value and b value of Haengbyung were decreased but the color a value and hardness were increased during the storage. The reducing sugar contents and gelatinization of Haengbyung with the raw apricot juice was decreased less than those with the steamed apricot juice during the storage. the moisture contents of Haengbyung were decreased less than Baeksulgi. Color b value of Haengbyung with the raw apricot juice was decreased less than that with the steamed apricot juice. The consistence, moistness, texture and overall quality of Haengbyung were generally more favorable than Baeksulgi based upon the sensory evaluation during the storage. Throughout the storage, consistence, moistness and texture of Haengbyung with the rqw apricot juice were generally more favorable than those with the steamed apricot juice. With respect to overall quality, Haengbyung with the addition of 15% apricot juice of rice flour weight was generally the most favorable during the storage.

• Food Science and Preservation
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• v.4 no.1
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• pp.1-10
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• 1997

This study was performed to determine chemical compositions of dried persimmons stored with plastic film at low temperature and the effect of film packaging on dried persimmons during storage. The moisture contents of dried persimmons were 30 to 36% and alcohol contents were 264 to 318 mg/100g and acetaldehyde contents were 25 to 40mg/100g. Total lipid contents of dried persimmon were 626 to 869mg/100g and oleic, palmitic, linolenic, and palmitoleic acid were major fatty acids in total lipids. Major amino acids were glutamic acid, arginine, cystine and aspartic acid. From the result of storage experiment, non-packed group was that hardness was high as decreased in moisture content. In case of film packed groups stored at 5$^{\circ}C$, self life was longer than non-packed and packed groups stored at room temperature. But, it need to develop available packing material and storage method.

• Journal of Biosystems Engineering
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• v.24 no.3
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• pp.235-242
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• 1999

This study was conducted to develop a grain moisture meter using microwave free space transmission technique at X-band frequency. The 10.5GHz microwave oscillator using a dielectric resonator was designed and fabricated to transmit electromagnetic wave through standard horn antenna to a sample holder with the wetted Hwasung and Chuchung rough rice(12.00∼26.25%). To detect the output voltage of transmitted wave from receiving horn antenna, the detector was composed of shottkey diode and RF impedance matching circuit. The regression model for measurement of grain moisture content was developed. Its correlation coefficient and standard error of prediction (SEP) were found to be 0.9882 and 0.657 respectively between measure and predicted moisture contents.