• Korean Journal of Food Science and Technology
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• v.9 no.4
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• pp.245-250
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• 1977

Experiment were conducted to find out the effective drying method of citrus peel produced in Korea by varying the temperature of hot air, surface area of peels, peels from several citrus varieties and physicochemical treatment of the peel. 1. About $3{\sim}6\;days$ were required to reduce the moisture level of the peel from 70%(wet basis) to 20% at room temperature without forced convection. 2. Drying was speeded up until the temperature of hot air reached $60^{\circ}C$. Beyond that no significant increase in drying rate was observed. About 50 minutes were needed to reduce the moisture level (dry basis) to below 10% at $60^{\circ}C$ by forced convection 3. When the peel surface area was increased twice by cutting the peel into 256 fractions, the overall drying time (the time required to reduce the moisture level to 10%, dry basis) was shortened to 15 minutes from 50 mintes of the original peel. 4. No significant difference in drying rate was observed among the peels from several citrus varieties except Shaddock jabon and Citrus ponki tanaka, which dried more slowly than others. 5. Treatment of $Ca(OH)_2$ and the pressing of the peel before drying were effective in drying only when the initial moisture content was substantially higher.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1086-1092
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• 2003

This study was carried out to investigate the effectiveness of blanching on the different drying methods and to examine the quality properties of carrots dried by freeze., vacuum- or hot air-drying during storage. Blanched carrots (BC) dried faster than raw carrots (RC), while RC showed more effective rehydration than BC by hot air- and vacuum-drying methods. There was more stability for BC on carotene retention and browning degree than RC in all drying methods during storage. Moreover, firmness of RC and BC by vacuum-drying was slightly lower than that of hot air-drying, but higher than freeze-drying. In firmness, BC and RC showed similar trends with different drying methods (decreasing with increased storage periods), while BC showed about 3 time firmer texture than RC in all cases during storage. The dried carrots prepared with blanching treatment showed more fine structures than those not treated. These results showed that the blanching treatment of carrots was good for maintaining quality by various drying methods.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.10
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• pp.886-893
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• 2000

A good understanding of the heat transfer distribution is very important to suppress the deformation of steel products. In this study, the local heat transfer coefficients are experimentally investigated to understand the heat transfer distribution of thick steel plates with even flat spray nozzle. The steel slabs are cooled down from the initial temperature of about $1000^{\circ}C$ , and the local heat transfer coefficients and surface temperatures are calculated from the measured temperature-time history. The results show that the local heat transfer coefficients of spray cooling are dominated by the local droplet flow rate, and in proportion to becoming more distant from the center of heat transfer surface, the local heat transfer coefficients decrease with the decrease of the local droplet flow rate.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.4 no.1
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• pp.22-30
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• 1971

Sea mussel Mytilus edulis, world-widely distributed, is a sort of popular food in Korea. The demands of high quality and mass production are not being satisfied since it is usually sun dried. A rapid dehydration and the treatment of food additives to improve the quality of the product seems to be required. In this paper, the effect of antioxidants and EDTA treatment was studied when sea mussel was pressed and hot-air dehydrated for 10 hours at 45 to $52^{\circ}C$ under the air flow rate of 3 meter per second. The results are as follows: 1) Cooked and pressed sea mussel was dehydrated mere rapidly than cooked without pressing. 2) The rehydration rate of pressed and dehydrated sea mussel was higher than that of the unpressed. 3) Among six samples, BHA treated material showed the best color preservation during dehydration and storage. The treatment of Teonox-II was also effective following BHA. 4) The effects of antioxidants used during dehydration and storage were in order of BHA, Tenox-II and NDGA treatment, while EDTA was ineffective. 5) No significant difference in rehydration rate was found between those treated with antioxidants or EDTA and the untreated. 6) The amount of soluble protein was higher in the samples treated with antioxidants than in EDTA treated or untreated samples. 7) The results suggest that the treatment of BHA and pressing process produce improved product in quality which gives higher amount of soluble protein and better rehydration, color preservation and preventive effect of rancidity.

• Corrosion Science and Technology
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• v.10 no.1
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• pp.24-29
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• 2011

The greatest purpose of chromate treatment is to improve anti-corrosion by stabilizing a metal surface. Because metal surface forms a compound by absorbing oxygen or water in the air by being generally unstable, it is necessary to improve anti-corrosion of the metal by forming the metal surface with a stable film. When considering the economical efficiency and requirements together because the film of the metal surface treated with chromate has good anti-corrosion and the stability also in the air by being compact and strong, Chromate treatment has been used most up to the electronics industry from the auto industry. However, these days, because hexavalent chromium is both a toxic agent to be able to cause cancers and deadly poisonous environmental pollutant, the strong legal controls on its use is being imposed all over the world. Because of this reason, a new anti-corrosion method is being required. Also, by users' various demands, the passivations that have recently been developed require various characteristics such as conductivity, chemical resistance, alkali cleaning resistance as well as anti-corrosion. We could confirm the results such as excellent anti-corrosion compared to chromate, conductivity, chemical resistance and detergent resistance as the result of analysis of various characteristics of the galvannealed sheet steels coated with Cr-Free solution developed in this research.

• Food Science and Preservation
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• v.21 no.5
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• pp.646-651
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• 2014

To evaluate the processing adaptability of burdock (Arctium lappa L) tea, the physicochemical properties of burdock tea treated with steaming and roasting were investigated. The tea treatments included hot-air drying after roasting (HDR, drying at $60^{\circ}C$ for 6 hr), steaming after hot-air drying (SHD, steaming at $100^{\circ}C$ for 10 min), and steaming and then hot-air drying followed by roasting (SHDR, roasting at $250^{\circ}C$ for 3 min). The physicochemical properties, antioxidant activities, and sensory properties of the HDR, SHD, and SHDR teas were measured in hot water, and the tea was extracted from each sample. The color values of lightness (L) and yellowness (b) were lower in the HDR and SHDR teas, and the total sugar content of the SHDR tea was significantly higher than that of the other teas. The ABTS and DPPH radical scavenging abilities of the SHDR tea with a 500 mg% concentration were significantly higher than those of the SHD tea. In the sensory evaluation, the SHDR tea was ranked significantly higher than the other samples as to its color, flavor, taste, and overall acceptability. The results suggest that SHDR can be applied to burdock tea to achieve high quality and functionality.

• Korean Journal of Medicinal Crop Science
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• v.25 no.6
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• pp.397-403
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• 2017

Background: This study was aimed at evaluating the growth, yield, and carbohydrate content in the whole Allium hookeri plant with shading treatment in hot summer. Methods and Results: Different shading rate, including 0 (control), 35 or 55%, was employed from the June $21^{st}$ to August $31^{st}$. Daily average air and soil temperature, which were approximately $2.5^{\circ}C$ and $3.8^{\circ}C$ lower, respectively, were observed with both 35% and 55% treatments in July and August, with no significant difference in daily maximum air temperature. Dry weights were high, approximately 40% and 48% for the shoot and 20% and 12% for the root, with the 35% and 55% treatments, respectively, 8 weeks after shading. Division number was increased by 13% and 19.8% with the 35% and 55% treatments, respectively. The mortality rates of 150 plants were 9.1%, 4.0%, and 1.3% with the 0 (control), 35% and 55% treatments, respectively. At 4 weeks after shading, the highest and lowest sucrose levels in both shoot and root were observed with the 35% and 55% treatments, respectively. At 8 weeks after shading, there was no significant difference in the sucrose content in the shoot among the treatments. Conclusions: The highest plant growth rate and yield with the 55% treatment may be related with the decrease in both air and soil temperatures, resulting in reducted leaf respiration and thus compensate net photosynthesis.

• Journal of the Korean Society for Heat Treatment
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• v.8 no.3
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• pp.197-204
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• 1995

In recent work, we reported that a hot-rolled Fe-18wt%Mn alloy exhibited high damping capacity as well as excellent mechanical properties. It was also proposed that damping capacity of the alloy was proportional to the ${\gamma}/{\varepsilon}$ boundary area. In the present study, the effects of homogenization(12hrs at $1100^{\circ}C$) and solution treatment(1hr at $1050^{\circ}C$ before air cooling) on damping capacity and mechanical properties were investigated for as-cast and heat treated Fe-18wt%Mn alloy. The specimen subjected to both homogenization and solution treatment was found to show superior damping capacity and mechanical properties to the as-cast state due to removal of segregation and increase in ${\gamma}/{\varepsilon}$ boundary area.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.9
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• pp.1338-1344
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• 2016

The present study was carried out to evaluate the anti-obesity effect of different concentrations of extracts of hot air-dried ramie leaf (HR) and freeze-dried ramie leaf (FR) in 3T3-L1 cells and pig preadipocytes. To analyze the effect on cell proliferation, cells were treated with $25{\mu}g/mL$ or $100{\mu}g/mL$ HR or FR extract for 2 days. Cell differentiation was evaluated by measuring glycerol-3-phosphate dehydrogenase and lipoprotein lipase (LPL) activities and intracellular triglyceride content. Treatment with either HR or FR extracts inhibited the proliferation of 3T3-L1 cells and pig preadipocytes in a dose-dependent manner. HR extract treatment inhibited the differentiation of both cell types more effectively than FR treatment. The extent of triglyceride accumulation decreased significantly in both cells following either HR or FR treatment. Furthermore, LPL activity significantly decreased after treatment with HR or FR extract. These results indicated that HR and FR extracts may inhibit proliferation and differentiation of 3T3-L1 cells and pig preadipocytes. Further studies are needed to explore the anti-obesity effect of HR and FR extracts.

• The Journal of Korean Physical Therapy
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• v.13 no.1
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• pp.175-188
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• 2001

The purpose of this study was to investigate the effect of the cold air application for release of inflamation and pain in patient with acute rheumatoid arthritis who had taken medication(NSAIDs, DMARDs, corticosteroids). The participants had knee joint pain and ESR score over the 30. They were randomly assigned to three groups with each 15. Control group(group I ) were applied cold air and medication, experimental group II were applied hot pack and medication. and experimental group III were applied only medication. They were evaluated from April 1, 2000 to september 1,2000 ,and it was examined by ESR and VAS(visual analoge scale) in Lee Bang Hoon rehabilitation medicine clinic in Jeju Korea. The result of this study were as follow: 1. It was found that group 1, group II and group III had the statistically significant reduction of the ESR score according to treatment time(p<.05). 2. There were not statistically significant differences in ESR change pattern of each group according to treatment time(p>.05). 3. There were not statistically significant differences in the change of ESR according to treatment time between group I and group II , group I and group III , and group II and group III (p<.05). 4. It was found that group I . group II and group III had the statistically significant reduction of the VAS(Visual Analoge Scale) score according to treatment time(p<.05). 5. There were statistically significant differences in VAS score according to treatment time between control group(group I ) and experimental groups(group II and group III)(p<.05), but there were not stsiistically significant differences between experimental groups(p>.05).