• Journal of Korean Society of Forest Science
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• v.83 no.2
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• pp.133-147
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• 1994

Wastepaper recycling has significant implications not only in providing scarce raw material input for the paper industry but in environmental concerns such as reducing solid waste disposal, energy conservation and preservation of forest resources. The objectives of this study was (1) to develop an econometric model of demand for and supply of wastepaper, (2) to forecast wastepaper consumption and price to the year 2000 applying the econometric models estimated and (3) to estimate the elasticity of variables which are included in the wastepaper supply and demand equations. In this study wastepaper was classified into three groups, old newsprint, old corrugated and mixed For each group such as demand and supply equation were estimated. The demand equations were estimated as a function of paper and paper product consumption and wholesale price index and supply equations as a function of wastepaper price, one year lagged paper and paperproduct consumption and transportation price. Applying the econometric models to forcasting results in the future consumption and supply of wastepaper projected as 11.645 million MT and 7.396 million MT in 2000, respectively. The rate of wastepaper self-supply is forcasted about 63.5% in 2000. Especially, the rate of old neswprint self-supply is predicted about 16% which means about 2.2 million MT of old newsprint should be imported from foreign countries. Lastly, some policy measures to promote wastepaper recycling rate based upon economic and physical characteristics of wastepaper and market structure are suggested.

• Journal of Energy Engineering
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• v.24 no.2
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• pp.9-16
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• 2015

As electricity is an indispensable input to human's existence and industrial production, economic benefits arise from consumption. The economic benefits of the electricity consumption are useful information in various fields of electricity-related policy. Therefore, this study attempts to value the economic benefits from electricity use. The economic benefit of electricity consumed is the area under the demand curve which made of the sum of the actual consumer expenditure and the consumer surplus. Consumer expenditure can be easily observed but the information on price elasticity of demand is necessarily required to compute consumer surplus. This study derives the estimates for price elasticities through literature review. The price elasticities of the electricity demand for residence, industry, and commercial are estimated to be -0.332, -0.351, and -0.263, respectively. Because the consumer surplus of the electricity consumption for residence, industry, and commercial are computed to be 191.54, 143.44, and 231.91 won per kWh, respectively. Given that average prices of electricity use were 127.02, 100.70, and 121.98 won per kWh for the year 2013, the economic benefit are calculated to be 318.56, 244.14, and 353.89 won per kWh, respectively. We can convert the values to 321.96, 246.75, and 357.67 won per kWh in 2014 constant price, respectively, using consumer price index. They can be used in the economic feasibility analysis of a new electricity supply project.

• Culinary science and hospitality research
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• v.22 no.3
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• pp.11-21
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• 2016

This study investigated the quality characteristics and retarding retrogradation of sponge cakes made with red yeast rice (RYR) flour. RYR (Monascus nuruk) is known to help digestion, smooth blood flow, and have anti-cancer, anti-microbial, and inhibitory effects against biosynthesis of cholesterol and blood pressure. This studys aim' was to find the optimal proportion of RYR flour in sponge cake. RYR sponge cakes were prepared with various levels (0, 5, 10, 15 and 20%) replacement of wheat flour and were designated as the control (without RYR), RYR5, RYR10, RYR15 and RYR20 respectively. Specific gravity was the lowest in RYR15 at 0.57, and the baking loss rate was not significantly different among the samples (p<0.05). The dough yield was the highest in RYR15 at 96.61. The moisture contents was highest in order, control, RYR5, and RYR15 at 28.67%, 28.18%, and 26.82% respectively. The L-value of crust tended to increase according to the level of RYR, but the L-value of crumb decreased in accorddance with the the content of RYR. The a-value of crust also decreased according to the level of RYR, although the a-value of crumb increased in response to higher levels of RYR. The b-value tended to decrease with increases of RYR (p<0.05). RYR5 exhibited the highest pH at 8.63, compared with RYR15 (8.57). The hardness, which was measured after cooling for 1 hour, was the lowest in RYR15 at $163.33g/cm^2$ and the springiness was not different significantly (p<0.05). Cohesiveness was the highest in RYR10 at 133.06%. The chewiness was the highest in RYR10 at $391.63g{\cdot}cm$ and lowest in RYR15 ast $169.62g{\cdot}cm$. Avrami equation showed that RYR15 and RYR20 had the lowest Avrami exponent (n) at 0.0664 and 0.4983 respectively. Time constant (1/k) was the highest in RYR15 at 200.00. Sensory evaluation revealed that RYR15 was the highest in color (5.50), flavor (4.95), sweetness (4.90), chewiness (4.75), and overall acceptability (4.60).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.1
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• pp.34-43
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• 1990

Six commerical rice varieties were cultivated and harvested at different locations in 1987 and 1988 to clarify the degree of locational variations. of several characteristics related to rice grain quality using the rice samples harvested from 8 to 20 locations for a variety each year. Locational variations of percent brown rice, percent milled rice, 1000-grain weight and amylose content were small, but whole grain rate, alkali digestibility, gel consistency, percent white-center and white-belly grain, degree of chalkiness and degree of translucency showed larger variations between locations. The degree of locational variation of sensory evaluation score for eating quality of cooked rice were varied from small to large along with rice variety used and year cultivated. Texture palatability index and stickiness of cooked rice among rheogram characteristics showed larger locational variations, but cohesiveness and springiness showed smaller variations between locations. Set back, break down and maximum viscosity showed larger locational variations among amylogram characteristics of rice flour. Special attention was given to a cultivated location, Anseong, because rice samples harvested at Anseong showed lower percent white-center and white-belly grain, and low set back and high break down in Chucheongbyeo, lower percent white-center and white-belly grain, higher texture palatability index and viscousness/hardness ratio, and low set back and high break down in Dongjinbyeo, higher texture palatability index, and low set back and high break down in Yongmunbyeo, lower percent white-center and white-belly grain in Sangpungbyeo, and low set back and high break down in Samkangbyeo. No other locations in this study produced rice samples showing wide acceptable quality-related characteristics except Anseong.

• Culinary science and hospitality research
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• v.21 no.3
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• pp.168-180
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• 2015

This study set out to make sponge cake a product of confectionery and bakery to expand the uses of rice bran and conducted a preliminary experiment to revise and supplement the addition of rice bran. The study sought to determine the level of added rice bran, 0~20%, by taking into account the taste, color, and marketability of rice bran in order to provide basic data for the possibilities of new product development and increase the usage of rice bran. As for the general composition, moisture, protein, fat, carbohydrate, and ash content comprised 9.50%, 15.51%, 18.12%, 48.17%, and 8.70% of the rice bran powder respectively. The pH of the dough decreased significantly with increased levels of rice bran. The specific gravity of the dough tended to rise significantly with the addition of rice bran. The group of 0% rice bran powder recorded the highest score of brightness, whereas the group of 20% rice bran powder scored lowest in terms of brightness. While there were significant differences between the control and experiment groups, no significant differences were found among the addition groups. Hardness also showed a tendency to significantly increase. The sensory evaluation results indicate that the group of 0% rice bran powder recorded the highest overall preference score at 5.00 and that the group of 20% rice bran powder had the lowest overall preference score at 2.87. The results also suggest that 10% rice bran powder sponge cake could be helpful in improving physical quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.12
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• pp.1792-1798
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• 2016

This study investigated quality characteristics, antioxidant activities, and retarding retrogradation of Sulgidduck, traditional rice cake of Korea, prepared using rice flour added with 0%, 1%, 2%, 3%, and 4% pumpkin leaf powder. Moisture content of pumpkin leaf Sulgidduck showed a tendency to increase in the 1% and 2% added group but decrease in the 3% and 4% added group. pH level significantly increased (4.50~6.16) with an increase in content of pumpkin leaf powder (P<0.05). For color, as content of pumpkin leaf powder increased, L-value decreased and b-value increased. Hardness tended to increase with addition of pumpkin leaf powder except for the 1% added group. Springiness was not significantly different (P<0.05). Chewiness and adhesiveness increased according to addition level increase. Retarding retrogradation showed that the pumpkin leaf powder added group had a stronger effect compared to the control, whereas the 2% added group presented the most retarding retrogradation effect with the lowest Avrami exponent. Total phenols content and ABTS radical scavenging activity tended to increase as content of pumpkin leaf powder increased. Sensory properties by 7-point scale test showed that the 2% added group had the highest scores, whereas the 4% added group had the lowest scores. These results suggest that pumpkin leaf is considered as a good material to improve quality characteristics, antioxidant activities, and retarding retrogradation of Sulgidduck. The most appropriate proportion for the greatest effect of retarding retrogradation in Sulgidduck was considered to be 2%.