• Magazine of the Korean Society of Agricultural Engineers
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• v.16 no.1
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• pp.3293-3301
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• 1974

An experimental work was conducted by using a laboratory-made model dryer to investigate the effect of the rate of natural forced-air on the drying rate of rough rice which was deposited in the deep-bed. The dryer consisted of 8 cylinderical containers with grain holding screen at their bottoms, each of which having 30cm in diameter and 15cm in height. The containers were sacked vertically with keeping them air-tight by using paper tape during dryer operation. Two separate layers of containers were operated in the same time to have two replications. The moisture contents of grains within each bins after predetermined period of dryer operation were determined indirectly by measuring the weight of the individual containers. The air-rates were maintained at 6 levels, or 5, 8, 10, 15, 18 and 20 millimenters of static head of water. The roomair conditions during dryer operation were maintained in the range of 10-l5$^{\circ}C$ in temperature and 40-60% in relative humidity. The results of the study are summarized as follows: 1. Drying characteristics of the grains in the bottom layers were approximately the same regardless of airdelivery rates, giving the average drying rate as about 0.35 percent per hour after 40-hour drying period, during which moisture content (w. b.) reduced from 24 percent to about 10 percent. 2. After about 40-hour drying period, the mean drying rates increased from 0.163 percent per hour to 0.263 percent per hour as air-flow rates increased from 5mm to 87.16mm of static head of water. In the same time, the moisture differences of grains between lower and upper layers varied from 12.7 percent at the air rate of 5mm of water head to 7.5 percent at the air-flow rate of 20mn of water head. Thus, the greater the air-flow rate was, the more overall improvement in drying performance was. Additionally, from the result of ineffectiveness of drying grain positioned at 70cm depth or above by the air rate of 5mm of static head of water it may be suggested in practical application that the height of grain deposit would be maintained adequately within the limits of air-rates that may be actually delivered. 3. Drying after layer-turning operation was continued for about 30 hours to test the effectiveness of reducing moisture differences in the thick layers. As a result of this layer-turning operation, moisture distribution through layers approached to narrow ranges, giving the moisture range as about 7 percent at air-flow rate of 5mm head of water, about 3 percent at 10mm head about 2 percent at 15mm head, and less than 1 percent at 20mm head. In addition, from the desirable results that drying rate was rapid in the lower layers and dully in the upper layers, layer-turning operation may be very effective in natural air drying with deep-layer grain deposit, especially when the forced air was kept in low rate. 4. Even though the high rate of air delivery is very desirable for deep-layer natural-air drying of rough rice, it can be happened that the required air delivery rate could not be attained because of limitation of power source available on farms. To give a guide line for the practical application, the power required to perform the drying with the specified air rate was analyzed for different sizes of drying bin and is given in Table (5). If a farmer selects a motor of which size is 1 or {{{{1 { 1} over {2 } }}}} H.P. and air-delivery rate which ranges from 8~10mm of head, the diameter of grain bin may be suggested to choose about 2.4m, also power tiller or other moderate size of prime motor may be recommended when the diameter of grain bin is about 5.0m or more for about 120cm grain deposit.

• Korean Journal of Community Nutrition
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• v.10 no.3
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• pp.290-302
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• 2005

The nutrients intake and health-related habits of nonagenarian subjects in Korean representative longevity belts of Damyang, Gokseong, Kurye, Sunchang were evaluated for the purpose of providing the information on the desirable food selection and dietary pattern of elderly population. A survey was conducted with 91 subjects (26 males and 65 females) and their food intakes were measured by the combination of one meal weighing and 24-hr recall, and their general background information was collected by visit. The mean age of the subjects was 93.6 $\pm$ 2.2 (male) and 97.6 $\pm$ 4.6 (female) The average smoking rate was $20.9\%$, the rate of regular drinking was $26.4\%$. The average energy intake was 1,284.9 kcal comprising $77.1\%$ of RDA for elder people over 75. The energy ratio of carbohydrate, protein and fat were 66.5 : 18.2 : 15.3. The average intake of protein, calcium, iron and zinc were $107.4\%,\;59.9\%,\;106.3\%$ and $60\%$ of RDA respectively. The lower intake of vitamins as low as $70\%$ was found except vitamin $B_6$ and niacin. The majority of the subjects consumed rice as staple diet and mostly consumed white plain rice rather than mixed grain rice. The animal and plant food intakes were 88.4 : 11.6 in males and those of females were 83.0 : 17.0 showing a tendency of plant-based meals. Nutrients that showed NAR over 0.7 were protein, iron, vitamin $B_6$, niacin and phosphate, but those with INQ over 1. Nutrient with INQ below 0.7 was only vitamin E. Even though their nutritional quantity did not appear to be enough, but their nutritional quality was relatively high. The adding dairy products, nuts and fruits for the purpose of proving sufficient vitamin and minerals can achieve the optimal nutritional intake patterns. Further research on RDA of this age population should be followed.

• Journal of Biosystems Engineering
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• v.5 no.1
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• pp.33-42
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• 1980

This study was carried out to investigate the actual environmental paddy storage conditions in conventional Korean farm warehouses. The paddy storage conditions by the locations and sizes of warehouses were figured out. The effectiveness of the small insulated box for storing paddy was also examined. Observations were made at sixteen different warehouses located in Moonsan-Myeon, Jinyandg-gun, Gyungnam Province from July lst to September 28 th, the period which was considered to be the worst for storing grains. The results are as follows ; 1. the average temperatures of rough rice and air inside the warehouse were 0.9 and 0.7$^\circ$ higher than the outside air temperature. 2. The average relative humidity in warehouses was 1.5percent higher than that of the atomosphere. This fact resulted in the increased moisture content of grains. Therefore, the ventilation for equalizing the relative humidity of inside and outside of warehouses was required. 3. The dry matter of stored rough rice was decreased by 1.1 percent in average druing the observation period. In order to reduce the dry matter loss, application of new grain storing method ;hermetic storage or filling inert gas storage, was highly recommended. 4. Environmental conditions for storing rough rice in a warehouse located in a sloping site are, in general , better than those of a warehouse located in a flat site. But as far as the dry matter of rough rice was concerned, above situation is not always satisfactory. Because it is fairly frequent to observe the higher rate of moisture absorption by grains stored in a warehouse located in a sloping site. 5. Environmental conditions for storing rough rice in a large-scale warehouse were better than those in a small size warehouse. Therefore, it is advisible for farmers to store their grins in the large-scale warehouses commonly used by villagers. 6. It was undesirable to store rough in a insulated box.

• Journal of the Korean Society of Clothing and Textiles
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• v.2 no.1
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• pp.157-166
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• 1978

The purpose of this study was; (1) to examine ready-to-wear dresses to find the characteristics of labels and construction which existed at three different price levels and (2) to make the gathered information available to consumers, designers, manufacturers and the people who are concerned with ready-to-wear garments. A check sheet was made listing a wide variety of features which could cause garments to be different. For the statistical analysis. 87 dresses were used out of 116 dresses examined. Observation was made at the stores in Myung Dong, Suh-Dae Moon and No Ryang Jin in Seoul from February 16, 1978 to March 3, 1978. The findings are; 1. The average prices of high, medium and low priced levels were ${\\}54,728$, ${\\}41,448$ and ${\\}7,225$. The average price discrepancy between high and medium priced levels was ${\\}13,000$ and ${\\}34,194$ between medium and low priced levels. 2. Most of the dresses examined had labels in all three priced levels. The most informative labels were found on medium priced dresses and then high. The low priced dresses had no information which would be of help to the consumer in regard to care, size and Jiber content. 3. Most of the dresses examined were cut on lengthwise grain. The stitching of medium and high priced levels were satisfactory. The chief way of fastening threads at the end of stitching was by backtracking. $28\%$ of the low priced levels was found unappropriate in stitching number because it was too large to the fabric. Many dresses in low priced levels were not pressed well. The average hem width of low priced dresses were less than 3cm, the high 3-4cm and the medium 4-5cm. Hemming was done mostly by hand in high and medium and by machine in low priced dresses. The medium priced dresses used more linings than low and high priced dresses.

• Tunnel and Underground Space
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• v.14 no.5
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• pp.363-372
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• 2004

Double torsion (DT) tests were carried out to investigate the influence of the geometry of guide groove on stress corrosion index of Kumamoto andesite. The fracture toughness was measured in the constant displacement rate, which was set to 2.07 MN/m$^{3}$2/ in average regardless of crack velocity. Stress corrosion indices, n were evaluated using specimens with rectangular, circular and triangular grooves and were 37, 36 and 38 in average, respectively. The n values were constant regardless of the groove geometry, however the DT specimen with triangular groove geometry showed the largest standard deviation in the relationship between crack velocity and stress intensity factor. The DT test was found to be effective in using a rectangular-grooved specimen and the width of the groove must be greater than the average grain size of minerals.

• Transactions on Electrical and Electronic Materials
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• v.6 no.6
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• pp.245-248
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• 2005

The physical and electrical properties of polycrystalline $\beta$-SiC were studied according to different nitrogen doping concentration. Nitrogen-doped SiC films were deposited by LPCVD(1ow pressure chemical vapor deposition) at $900^{\circ}C$ and 2 torr using $100\%\;H_2SiCl_2$ (35 sccm) and $5 \%\;C_2H_2$ in $H_2$(180 sccm) as the Si and C precursors, and $1\%\;NH_3$ in $H_2$(20-100 sccm) as the dopant source gas. The resistivity of SiC films decreased from $1.466{\Omega}{\cdot}cm$ with $NH_3$ of 20 sccm to $0.0358{\Omega}{\cdot}cm$ with 100 sccm. The surface roughness and crystalline structure of $\beta$-SiC did not depend upon the dopant concentration. The average surface roughness for each sample 19-21 nm and the average surface grain size is 165 nm. The peaks of SiC(111), SiC(220), SiC(311) and SiC(222) appeared in polycrystalline $\beta$-SiC films deposited on $Si/SiO_2$ substrate in XRD(X-ray diffraction) analysis. Resistance of nitrogen-doped SiC films decreased with increasing temperature. The variation of resistance ratio is much bigger in low doping, but the linearity of temperature dependent resistance variation is better in high doping. In case of SiC films deposited with 20 sccm and 100 sccm of $1\%\;NH_3$, the average of TCR(temperature coefficient of resistance) is -3456.1 ppm/$^{\circ}C$ and -1171.5 ppm/$^{\circ}C$, respectively.

• Korean Journal of Medicinal Crop Science
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• v.23 no.1
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• pp.8-12
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• 2015

Characteristic of seed for Sageretia thea fruits collected from the habitat of harvest season in Jeju and their germination ratio in different temperatures were considered. The average weight was 0.2 g, average diameter was 7.2 mm, average length was 6.5 mm, and size distribution range was 5.1 ~ 10.0 mm. The number of seeds per fruit was 1.8, and 1000 grain weight was 7.77 g with diameter of 3.7 mm and thickness of 1.7 mm in size. The fruit maturation was investigated to be from April 27 to June 1, when the best maturation period was about a week, May 11 to May 18. Also, the fruits grown on May 4 to May 11 were seen to have the bigger in transverse size and weight with a tendency of the earlier maturation date has the greater the number of seeds. S. thea seeds pretreated for 24 hours at $50^{\circ}C$ were not germinated, while most of those pretreated for 24 hours at $4^{\circ}C$ were successfully germinated at any degree of temperature (except at a temperature of $10^{\circ}C$). Particularly, the highest germination rate of 55% was made at $15^{\circ}C$, and plumule and radicle were best grown within the temperature range of $25^{\circ}C$.

• The Korean Journal of Ceramics
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• v.2 no.2
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• pp.102-110
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• 1996

The Mg-PSZ/$Al_2O_3$ fibers were fabricated by the sol-gel method. The added $Al_2O_3$ amounts were varied from 5 to 20 mol%. The phase transformation studies of a drawn Mg-PSZ/$Al_2O_3$ fibers were investigated by use of X-ray diffraction, IR and Raman spectroscopy. Microstructure and tensile strength of fibers were subjected to scanning electron microscopy and tensile strength tester. When $Al_2O_3$ was added to the Mg-PSZ fibers, it was found out from the analysis of XRD patterns and Raman spectra that a small amount of crystalline spinel($MgAl_2O_4$) started to form due to the reaction between $Al_2O_3$ and MgO, at $1000^{\circ}C$, and the phase transformation temperature of $ZrO_2$ crystal phase at different sintering temperatures increased. Also, the rapid grain growth with average size of 2.0 ${\mu}m$ shown in Mg-PSZ fiber at $1500^{\circ}C$ was considerably suppressed to 0.39 ${\mu}m$ by adding $Al_2O_3$ at the same temperature. When the Mg-PSZ/$Al_2O_3$ fibers containing 5 mol% $Al_2O_3$ were sintered $800^{\circ}C$ for 1 hr, average tensile strength of fibers was 0.9 GPs at diameters of 20 to 30 ${\mu}m$, but as the sintering temperatures was increased to $1000^{\circ}C$ for 1 hr, average tensile strength of fibers increased to 1.2 GPa in the same diameter range.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.31 no.6
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• pp.403-407
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• 2018

In this study, double layer KTN/STO thin films were fabricated on $Pt/Ti/SiO_2/Si$ substrate, their structural and electrical properties were measured according with the number of STO coatings, and their applicability to microwave materials was investigated. The average grain size was about 80~90 nm, the average thickness of the 6-coated KTN thin film was about 320 nm, and the average thickness of the STO thin film coated once was about 45~50 nm. The dielectric constant decreased with increasing frequency, and as the number of STO coatings increased, the rate of change of the dielectric constant with the applied electric field decreased. The tunability of the KTN thin film showed a maximum value of 19.8% at 3 V. The figure of merit of the KTN/1STO thin film was 9.8 at 3 V.

• Korean Journal of Community Nutrition
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• v.9 no.3
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• pp.315-325
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• 2004

This study was conducted to develop the standard breakfast menu for those weak groups having insufficient breakfast intake. The following three target groups are classified as: 16-19 years old high school male student, 20-29 years old female who have job or college students, 20-29 years old male or female who have job (double income family). While developing menus for each target groups, we applied several basic guidelines for meal planning as follows: Nutrient intake level was set to $\graction one-Third$ of RDA, while the energy level to $\fraction one-quarter $ of RDAs. Most Sequent meal pattern of Koreans was adapted; Suitabilities of appropriate serving size and cost for middle-income families were considered; Domestic foods and ingredients were used. We developed 24 menus summed by 2 menus for each season and three target groups. When evaluating the menus, most of the breakfast menus were sufficient of nutrients as a meal for the subjects. Three food groups such as grain/starch group, meat/fish/egg/bean group, vegetable/fruit group were included in all menus. Even though milk/dairy products group was not excluded for some menus, other calcium substitutes like anchovies were used. Oil/nut/sugar group was used to a minimum. The average number of foods for each menu was 12.8, which ranged from 10 to 17 depending on the menus. The average weight of the menus including soup was 822 g, 633 g and 730 g for each target group, respectively. The average price of the menu ranged from 2,000 to 3,500 won per person. The above results could be applied at home as well as foodservice institutes and furthermore could offer information for developing breakfast-substituting food products.