• Title/Summary/Keyword: Composition Rate

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A Study on the Load Composition Rate Estimation Considering Reliability of Hourly Load Data and a Method for Enhancement of Data Quaility (시간별 부하자료의 신뢰도를 고려한 부하구성비 추정 및 데이터 품질 향상 방안에 관한 연구 -산업용 부하를 중심으로-)

  • Hwang Sung-Wook;Kim Jung-Hoon
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.55 no.2
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    • pp.67-69
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    • 2006
  • A load composition rate estimation algorithm is developed for DSM evaluation system. The algorithm has the structure which is composed of data verification and development and can enhance the data quality Also a hourly weighting function is introduced for maintaining load shapes. The load composition rates of specific industrial customers are obtained and the results of case studies show that a reasonable load composition rate is achieved. Additionally qualify function deployment (QFD) is introduced to enhance quality and reliability of data.

Composition and interface quality control of AlGaN/GaN heterostructure and their 2DEG transport properties

  • Kee, Bong;Kim, H.J.;Na, H.S.;Kwon, S.Y.;Lim, S.K.;Yoon, Eui-Joon
    • Journal of Korean Vacuum Science & Technology
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    • v.4 no.3
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    • pp.81-85
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    • 2000
  • The effects of $NH_3$ flow rate and reactor pressure on Al composition and the interface of AlGaN/GaN heterostructure were studied. Equilibrium partial pressure of Ga and Al over AiGaN alloy was calculated as a function of growth pressure, $NH_3$flow rate and temperature. It was found equilbrium vapor pressure of Al is significantly lower than that of Ga, thus, the alloy composition mainly controlled by Ga partial pressure. We believe that more decomposition of Ga occur at lower $NH_3$ flow rate and higher growth pressure leads to preferred Al incorporation into AlGaN. The alloy composition gradient became larger at AlGaN/GaN heterointerface at higher reactor pressures, higher Al composition and low $NH_3$ flow rate. This composition gradient lowered sheet carrier concentration and electron mobility as well. We obtained an AlGaN/GaN heterostructure with sheet carrier density of ${\sim}2{\times}10^{13}cm^{-2}$ and mobility of 1250 and 5000 $cm^2$/Vs at 300 K and 100 K, respectively.

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Effects of Bedding Materials and Season on the Composition and Production Rate of Broiler Litter as a Nutrient Resource for Ruminants

  • Park, K.K.;Yang, S.Y.;Kim, B.K.;Jung, W.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.11
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    • pp.1598-1603
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    • 2000
  • Broiler litter can be used as a feedstuff for ruminants. Fifty seven litter samples collected from 47 farms in Kyungkee Province of Korea were analyzed to assess the effects of type and amount of bedding (rice hulls vs. sawdust), season (winter vs. summer) and drinkers (bell- vs. trough-type) on composition of broiler litter. Rearing conditions of broilers were also surveyed from the farms to estimate annual production rate of litter. Nutrient composition of broiler litter varied widely and moisture and ash concentrations were higher than observed by other researchers. Ash concentration was higher (p<0.05) for samples taken in winter than in summer and higher (p<0.05) in the rice hulls- than in the sawdust-based litter both in winter and summer. Only minor differences in litter composition were noted between drinkers. Ash was negatively correlated with crude protein and neutral detergent fiber (p<0.01), and acid detergent fiber (p<0.05). The estimated litter production rate was 2.7 kg per bird per flock on a wet basis (60% DM) and the annual production rate was 12.7 kg per bird per yr (60% DM). Therefore, the 42 million broilers per month grown in Korea in 1999 produced a total of 533,400 metric tons of litter.

Evaluation of 0ff-gas Characteristics in Vitrification Process of ion-Exchange Resin

  • Park, S. C.;Kim, H. S.;K. H. Yang;C. H. Yun;T. W. Hwang;S. W. Shin
    • Nuclear Engineering and Technology
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    • v.33 no.1
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    • pp.83-92
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    • 2001
  • The properties of off-gas generated from vitrification process of ion-exchange resin were characterized. Theoretical composition and flow rate of the off-gas were calculated based on chemical composition of resin and it's burning condition inside CCM. The calculated off-gas flow rate was 67.9Nm$^3$/h at the burning rate of 40kg/h. And the composition of off-gas was avaluated as $CO_2$(41.4%), steam(40.0%), $O_2$(13.3%), NO(3.6%), and SO$_2$(1.6%) in order. Then, actual flow rate and composition of off-gas were measured during pilot-scale demonstration tests and the results were compared with theoretical values. The actual flow rate of off-gas was about 1.6 times higher than theoretical one. The difference between theoretical and actual flow rates was caused by the in-leakage of air to the system, and the in-leakage rate was evaluated as 36.3Nm$^3$/h. Because of continuous change in the combustion parameters inside CCM, during demonstration tests, the concentration of toxic gases showed wide fluctuation. However, the concentration of CO, a barometer of incompleteness of combustion inside CCM, was stabilized soon. The result showed quasi-equilibrium state was achieved two hours after feeding of resin.

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Current Composition Table of Foods in Japan and Future Trends

  • Watanabe, Tomoko
    • Journal of Community Nutrition
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    • v.5 no.2
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    • pp.65-71
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    • 2003
  • In Current Standard Tables of Food Composition in Japan (Fifth Revised Edition), standard composition values of food used regularly in Japan are shown by values per 100g of their edible portion, with one value of standard composition per one foodstuff as a rule. In the Explanation (Chapter 1) and Reference Data (Chapter 4) of the original table, the most important matters are mentioned, including the table of the weight change rate by cooking, the table of the outline of the cookery, and the formula of the actual amount of intake nutrition. These are helpful for an understanding of the actual amount of intake nutrition. The formula for the amount of purchase in consideration of the amount of refuse is also shown. Information concerning foodstuffs and composition items in the table as well as important points in the reference column are concurrently written in English. As related studies, the composition tables by values per 100m1 or considered loss, the table or the formula for estimation of the amount of sucrose, and the list of the composition extant rate after cooking, among others, are also provided. Users should understand the original composition table, and then suggest how to utilize it. (J Community Nutrition 5(2) : 65∼71, 2003)

The Evolution of Rate of Profit and Its Determinants in Korean Economy (한국경제에서의 이윤율 변화와 결정요인들)

  • Yu, Won-Keun;Choi, Ho-Yeong
    • Journal of Digital Convergence
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    • v.12 no.2
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    • pp.89-97
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    • 2014
  • With regard to conventional theory, the rate of profit is determined by the interaction between the rate of surplus value and the organic composition of capital. And it declines with the capitalistic development through intensifying the organic composition of capital. According to the empirical test, the rate of profit and the rate of surplus value have been decreased. On the contrary, the organic composition of capital have increased during the period under study. The empirical results of the rate of profit in Korean economy appears to hold the principle of the law of the tendency of the rate of profit to fall. But the trend of the determinants is distinct from the conventional theory. Despite the distinctive empirical results, the law of the tendency of the rate of profit to fall is realized in Korean economy in objective period of time.

Study on the Mechanical Properties of TiAl Crystals Grown by a Floating Zone Method

  • Han, Chang-Suk;Kim, Sang-Wook
    • Korean Journal of Materials Research
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    • v.27 no.7
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    • pp.369-373
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    • 2017
  • Unidirectionally solidified TiAl alloys were prepared by optically-heated floating zone method at growth rates of 10 to 70 mm/h in flowing argon. The microstructures and tensile properties of these crystal bars were found to depend strongly on the growth rate and alloy composition. TiAl alloys with composition of 47 and 50 at.%Al grown under the condition of 10 mm/h showed $Ti_3Al({\alpha}_2)/TiAl({\gamma})$ layer structures similar to single crystals. As the growth rate increased, the alloys with 47 and 50 at.%Al compositions showed columnar-grain structures. However, the alloys fabricated under the condition of 10 mm/h had a layered structure, but the alloy with increased growth rate consisted of ${\gamma}$ single phase grains. The alloy with a 53 at.%Al composition showed a ${\gamma}$ single phase regardless of the growth rate. Room-temperature tensile tests of these alloys revealed that the columnar-grained material consisting of the layered structure showed a tensile ductility of larger than 4 % and relatively high strength. The high strength is caused by stress concentration at the grain boundaries; this enhances the secondary slip or deformation twinning across the layered structure in the vicinity of the grain boundaries, resulting in the appreciable ductility.

A study on the Poly-$Si_{1-x}Ge_x$ thin film deposition (I) Variation of the deposition rate and Ge composition with deposition parameters (다결정 $Si_{1-x}Ge_x$박막 증착에 관한 연구(I) 증착변수에 따른 증착속도 및 Ge조성 변화)

  • 이승호;어경훈;소명기
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.7 no.4
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    • pp.578-588
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    • 1997
  • Poly-$Si_{1-x}Ge_x$ films on oxidized Si wafer were prepared by rapid thermal chemical vapor deposition using the $SiH_4$ and $GeH_4$ gaseous mixture at various deposition conditions. The deposition temperature, $SiH_4\;: GeH_4$ flow ratio and pressure were varied from 400 to $600^{\circ}C$, 1 : 0.1-2 : 1 and 1 to 50 torr, respectively. In this work, we have investigated the change of Ge composition of poly-$Si_{1-x}Ge_x$ films deposited with the variation of deposition parameters and the effect of Ge composition on the deposition rate. From the experimental results, it was observed that the deposition rate increased with increasing deposition temperature and Ge composition. On the other hand, the Ge composition decreased with increasing temperature. As the deposition pressure increased, the deposition rate and Ge composition were increased linearly to 10 torr but increased slowly above it, which has been attributed to the slower rate of surface reaction than mass transfer.

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Effects of Dietary Composition, Feeding Satiation Rate and Feeding Frequency of Extruded Pellets on Growth and Body Composition of Flounder Paralichthys olivaceus (부상사료의 사료조성, 공급율 및 공급횟수가 넙치의 성장 및 체조성에 미치는 영향)

  • Seo, Joo-Young;Jang, Hyun-Seok;Kim, Kyoung-Duck;Kim, Gun-Up;Lee, Sang-Min
    • Journal of Aquaculture
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    • v.18 no.2
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    • pp.98-106
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    • 2005
  • A feeding trial of two extruded pellets (EPI, 45% crude protein with 7% crude lipid and EP2, 47% crude protein with 10% crude lipid)${\times}$ two satiation rates (satiation and 80% satiation)${\times}$ three feeding frequencies (three, two and one meal a day) factorial design with three replications was carried out to investigate the optimum feeding frequency and satiation rate for growth of juvenile flounder. Flounder averaging 55 g were fed a extruded pellets for 58 days. Daily feed intake was affected by dietary composition, feeding frequency and satiation rate (P<0.05). Weight gain of fish fed the EP1 and EP2 was not affected by both dietary composition and feeding frequency (P>0.05), but affected by feeding satiation rate (P<0.05). Weight gain of fish fed the each of EP1 and EP2 twice daily with satiation was the highest among treatments, but was not significantly different to that of fish fed the diets three times daily with satiation feeding. Feed efficiency and protein efficiency ratio of the fish were not affected by dietary composition, feeding frequency and satiation rate (P>0.05). Moisture, crude protein and crude lipid contents of the muscle of fish were affected by satiation rate. Moisture and crude protein contents of the liver were affected by dietary composition. Based on fish performance results, it can be concluded that the proper feeding frequency for the growth of juvenile flounder grown from 55 g to 90 g is two meals a day with satiation feeding, regardless of dietary composition used in this study.