• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.6
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• pp.2596-2603
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• 2013

The precision and endurance of tire mold are very important factors to decide the quality of tire. However, the investigation on the thermal deformation of tire mold has a lot of trouble because the tire mold is produced in airtight permanent casting material. In this study, the thermal deformations such as temperature, displacement and stress distributions inside the AC7A tire mold casting material were analyzed by numerical analysis according to the preheating temperature of permanent casting device. In order to verify the results of numerical analysis, the experiments for temperature measurement of the AC7A casting material were carried out under the same condition with numerical analysis. For the numerical analysis, "COMSOL Multiphysics" was used. The preheating temperatures were set up $150^{\circ}C$, $200^{\circ}C$, $250^{\circ}C$ and $300^{\circ}C$, respectively. The thermal deformations were calculated in each case. When the preheating temperature is $300^{\circ}C$, displacement and stress are the lowest with 0.25mm and 0.351GPa, but the temperature is the highest with $374.27^{\circ}C$. When the experimental results were compared with the numerical results, there were some temperature differences because of the latent heat by phase change heat transfer. However, the cooling patterns were almost similar except for the latent heat section.

• Journal of Korean Ophthalmic Optics Society
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• v.6 no.1
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• pp.133-137
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• 2001

The method to make glass is tried first thing in domestic study for glasses lens. Tg of glass KzFSl was measured by DSC experiment and press method of glass of meniscus shape was studied for minimize the cost. Tg was increased $483^{\circ}C$ to $501^{\circ}C$ with increasing heating rate $2^{\circ}C/min$ to $20^{\circ}C/min$. It shows Arrhenius temperature dependence and the activation energy of Tg is ${\Delta}E$=409 kJ/mole(4.25eV) by using Ozawa method and Tg is near $480^{\circ}C$. The melt of KzFSl powder was poured to concave cast stainless and pressed convex cast stainless. The quenched glass was slow cooled with cooling rate $0.25^{\circ}C/min$ in temperature range $520{\sim}430^{\circ}C$. The glass was made without strain. It has meniscus shape and same size to commercial glasses lens.

• Journal of Conservation Science
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• v.24
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• pp.13-22
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• 2008

The identification of species, hygroscopic property, and ability of ethylene gas absorption of 23 ancient charcoals excavated from wooden coffin burials and roof-tile kilns of Chudong-ri cultural site were investigated. All of the 12 charcoals excavated from wooden coffin burials were broad-leaved trees. Among the total 12 samples, 9 samples were Lepidobalanus and others were Celtis spp.. On the other hand, other 11 charcoals from roof-tile kilns were needle-leaved tree, Pinus spp.(hard pine). The broad-leaved tree charcoals from wooden coffin burials showed a higher moisture absorption capacity than needle-leaved tree charcoals from roof-tile kilns. The ethylene gas absorption was greater in the Lepidobalanus charcoal than that of Celtis spp. and Pinus spp. (hard pine) charcoal. The broad-leaved tree charcoal having high absorption ability of substances was due to a large microporous and specific surface area. Therefore, it was estimated that broad-leaved tree charcoals were filled in order to make favorable condition in tomb. The wood quality of pine is soft and easy to burn because of low specific gravity, as well as high calorific value by resin in wood. We could assume that the pine wood was used as fuel for roof-tile kilns because of easy control of heating and thermal power.

• Korean Journal of Food Science and Technology
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• v.17 no.4
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• pp.253-257
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• 1985

Effects of four kinds of phosphate complex on the water holding capacity (W.H.C) and protein solubility of yellow-corvenia (Pseudosciance manchurica) and hair tail (Tichurus lepturus) meat paste were investigated. The formulations of four kinds of phosphate complex employed to this experiment were made by mixing several phosphates such as sodium polyphosphate, sodium pyro-phosphate, sodium acid pyro-phosphate, potassium pyro-phosphate, sodium tetra meta-phosphate, sodium ultra meta-phosphate and sodium hexa meta-phosphate, and monoglyceride at different mixture ratios. Among the four kinds of phosphate complex, phosphate B complex which was formulated by mixing sodium poly-phosphate 50%, sodium pyrophosphate 20%, sodium tetra meta-phosphate 20%, sodium acid pyrophosphate 5% and sodium ultra meta-phosphate 5% was most effective on enhancing the W.H.C and protein solubility of yellow corvenia meat paste, and in case of hair tail meat paste, phosphate C complex which was formulated by mining sodium poly-phosphate 40%, sodium pyro-phosphate 30%, potassium pyro-phosphate 15%, sodium tetra meta-phosphate 10%, and sodium hexa meta-phosphate 5% was more effective than other phosphate complex, and their optimum addition level was 0.4% respectively in weight of fish meat paste. Texture characteristics such as hardness, cohesiveness, and springiness value of Kamaboko (fish meat paste product) were evaluated as best when 0.3% of phosphate B complex was added. The optimum cooking condition of Kamaboko to get good texture was heating for 45 mimutes at $85^{\circ}C$.

• Korean journal of food and cookery science
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• v.31 no.4
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• pp.395-404
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• 2015

The aims of this study were to determine the optimal mixing condition for two different amounts of Gynura procumbens powder and olive oil for the preparation of beef sausage. The experiments were designed according to the central composite design of response surface methodology, which showed 10 experimental points including two replicates of Gynura procumbens powder and olive oil. The physicochemical and mechanical characteristics as well as the sensory properties were measured, and these values were applied to the mathematical optimization models. The results of the physiochemical and mechanical analysis of each sample, including chewiness, cohesiveness, color a, color b, moisture content, salinity and heating loss showed significant differences. The sensory measurements were significantly different in color, flavor, tenderness, texture and overall quality. The optimum formulation, which was calculated using the numerical and graphical method, was determined to be 2.1 g Gynura procumbens powder and 7.06 g of olive oil.

• Applied Biological Chemistry
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• v.13 no.1
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• pp.29-34
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• 1970

In order to prepare digested Protein source for the Weanling Food from soybean, an attempt was made to decompose steamed soybean protein to amino acids and peptides by protease and cellulase produced from Aspergillus niger and Aspergillus sojae. In this paper, the optimum condition for digestion of soybean protein were studied and also investigated the effects of decolorization of it. As the results, followings were obtained; 1. As steaming conditions, a treatment under 15 lb of pressure and 10 minutes of heating shows most effective. 2. The optimum pH of Asp, sojae enzyme for the digestion of soybean protein is 6.0, while that of Asp. niger enzyme is 4.4. In successievly-decomposing with Asp. sojae and Asp. niger, it shows the most effective on ratio of water-soluble-nitrogen to total nitrogen and amino-nitrogen to total nitrogen than any other separate treatments. 3. The suitable amount of the enzyme solution to that of the soybean substrate paste, in volume, is 1 : 2. 4. Digestion ratio of soybean protein indicates the gradual and steady effects of increasing time of digestion, but 8 hour-digestion regarding to putrefaction was suitable. 5. The most effective decolorization was successively passed on culumns of active carbon and anion exchanger (Dowex 2-x-8) at room temperature. In separate treatments, the effective order of decolorization was as follows; (Dowex 2-x-8)>Active carborn>Amberite IR-120 6. The powder type of the soy protein source obtained by concentration below $60^{\circ}C$ contains 12.51% of moisture, 66.31% of protein, 4.25% of fat, 12.75% of carbohydrate, 4.18% of ash.

• Journal of the Korean Wood Science and Technology
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• v.38 no.1
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• pp.17-26
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• 2010

Recently, yellow poplar (Liriodendron tulipifera L.) is getting attention in Korea due to the fast growing and high yield and quality of lumber. But, it is thought that the color difference between heartwood and sapwood may restrict the practical use of it. This study was aimed to enhance the value of yellow poplar lumber by the color control using high temperature heat-treatment, which had been tried for domestic cedar (Kim et al., 2009). The material properties including surface color of yellow poplar lumber were evaluated according to heat treatment conditions. The difference of color between sapwood and heartwood could be reduced by heat treatment at a temperature about $200^{\circ}C$. Long heating time was more effective in reducing the difference. The Equilibrium Moisture Content (EMC) of heat-treated wood was as low as 50 percent of the control. The result obviously indicates that heat-treated wood is more dimensionally stable in the change of moisture condition. The durability against wood rotting fungi also increased by the heat-treated, but it was not so effective as the case of cedar. The changes of mechanical properties of heat-treated yellow poplar were very similar to that of heat-treated cedar. In order to develop new use of heat-treated yellow poplar, the changes of mechanical properties should be considered. There were no significant changes in microscopic structure which may cause changes in mechanical properties. Further study of heat-treated wood is needed to scrutinize the causes of changes of material properties.

• Land and Housing Review
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• v.3 no.4
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• pp.357-367
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• 2012

The efficient business scheme were suggested with the consideration of the local development condition at Ulaanbaatar. Major findings of the study were presented as follows. First, high level of education and the underground resources are presented as the merits of Mongolia. On the other side, the defects are limited domestic demands of 2.6 millions of population and the insufficiency of the infrastructure. The improvement of the infrastructures like roads, water & sewage, electric power, and heating is urgent while the development pressure of Ulaanbaatar is expected to be high due to the continuous inflow of population. Secondly, the Mongolian land system consists of the right of ownership, lease and use, therefore there are some differences among the right of land. Thirdly, definite business scheme to sell land in lots and to sell buildings in lots are suggested which are actual methods to participate in the development project in Ulaanbaatar. Moreover, enhancing the possibility to sell the lands, fixing the proper sale price to secure the profit, finding the proper buyer for the profitable lands, investing of quota and guaranteeing of granting the principal and interest by the Mongolian government, etc. are presented as consideration when participate in projects.

• Korean Journal of Food Science and Technology
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• v.33 no.3
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• pp.301-306
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• 2001

An invistigation was carried out to study the effects of heat treatment of garlic and storage temperature of garlic extracts on functional properties of garlic extracts. The garlic was heated at 40, 60, 80, 100, $120^{\circ}C$ for 10 minutes and extracted with 50% ethanol. The extracts were stored at 4, 25 and $50^{\circ}C$ for 30 days, and then electron donating ability(EDA), nitrite-scavenging effects(NSE) and total thiosulfinates contents were determined. Among the functional properties, total thiosulfinates were rapidly reduced as the heating and storage temperature increased. The total thiosulfinates in the extracts were not detected for those heat-treated at 100 and $120^{\circ}C$. The EDAs were also decreased to almost half of their initial level by heat treatment of garlic at higher temperature than $80^{\circ}C$ while NSE was decreased a little. As the storage temperature increased, EDA and thiosulfinate contents decreased. Particularly the thiosulfinates were ditected none after 11 days of storage at $25^{\circ}C$ and $50^{\circ}C$. Therefore, mild heat treatment of garlic at lower temperature than $60^{\circ}C$ and storage at refrigerated condition are recommendable for preparation and storage of garlic extracts.

• Journal of the Korean Home Economics Association
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• v.28 no.4
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• pp.65-86
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• 1990

Living conditions of the rural elderly were assessed in terms of clothing behavior, health and nutritional status, housing and envioronmental condition, and psychological adjustment. The subjects were eighty individuals over sixty residing in the rural community of Iksan-kun, Chollabukdo. The interview method using questionnaires, direct measurement, and observation was used for this study. Data were compared with those obtained from a previous study of the elderly residing in an urban area. Clothing behavior showed that the elderly residing in the rural community were more concerned about plain and conservative design of clothes than their urban counterparts. Special protective clothes for cropdusting with agricultural chemicals had not been prepared. The following urgent needs were pointed out: development and supply of agricultural chemical protective clothing and development and education of appropriate washing and clothing care methods. The health status of the elderly was generally good, but poor eating habits were found more frequently in the rural elderly than among the urban dwellers. Several dietary nutrient intakes were insufficient. Contrasting the urban elderly with the rural group, it was found that the urban group lacked sufficient vitamin A and vitamin C and the urban women had insufficient calorie whereas the rural group was deficient in protein, vitamin A, calorie, and fat. A significant relationship was found between dietary nutrient intake and health index, food habit points, self recognized health status, meal satisfaction, and economic status. Urgent needs of the development of a nutrition education program for the elderly were pointed out. Most of elderly residing in the surveyed rural communities were living alone or with their spouse only, therefore only one room was used among the three or four available rooms. Most of the rural elderly were living either in a traditional Korean house built with differing floor levels or in a modified Korean style house. Minimal modernization had been made for kitchen facilities such as sink and gas range or for heating facilities with the briquette boiler. However, sanitary space such as lavatory and bathroom had not been remodeled. A housing welfare program for rural communities should be implemented at the national level. The comparison of psychological characteristics of the rural elderly with their city counterparts revealed that the rural elderly have a more stable psychological status and optimistic attitude than those living in a city. However, it was found that most of the elderly did not have any future plan. Community programs for the elderly including hobbies or leisure activities or education programs to generate close interpersonal relationships with their children should be developed and provided.