• Bulletin of the Korean Chemical Society
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• v.18 no.7
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• pp.703-706
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• 1997

Response surface method was applied to the predicting optimum conditions of benzene synthesis for radiocarbon dating. The weight of carbon dioxide, the temperature of lithium container for producing acetylene and the activation temperature of catalyst which was used for the cyclization of acetylene to benzene were used as experimental factors. The yields of benzene synthesis were measured from twelve experiments which were carried out under various experimental conditions. The polynomial equation was obtained by using three experimental factors and yields. The validity of polynomial equation was confirmed by comparing the calculated yields with the experimental ones.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.324-329
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• 2001

Sediment yields from the reservoir watershed areas and raising of the spillway crest for the agricultural reservoir capacity enlargement were investigated and analysed through the 21 pilot reservoirs, have irrigated areas 200has. and over in the Kyoungpook province. In these studies, (1), the correlation analysis between various watershed characteristics and annual specific sediment yields were derived and (2), the excess effective reservoir capacity of the over 0.5m above the spillway crest could be estimated. In brief, catchment area should strongly be correlated with the annual specific sediment yields (R=0.90), the other side, average slope of the main stream is less than catchment area. The excess effective capacity of reservoir enlargement by the raising of spillway crest at 0.5m-height was resulted 12.1% of increasing capacity compare with the original reservoir capacity.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.527-530
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• 2003

In this study, physically based SWAT model was applied to estimate the daily stream flows and sediment yields in Gyeongancheon watershed. The calibration and validation of the model outputs have been performed with yearly and daily measured stream flows of the time period 1988-1991 and 2001. The application results showed a good agreement with the simulated and observed stream flows, and similar trend with simulated and observed sediment yields. Overall, SWAT is a reasonable watershed scale model on long-term simulations of stream flows and sediment yields for management purposes.

• Journal of Environmental Science International
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• v.27 no.3
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• pp.147-154
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• 2018

The purpose of this article is analyzing the impacts of seawater surface temperature rise on sea mustard yields of Goheung and Wando coast in Korea, with employing a panel data regression model. Our results show that there has been a negative impacts on sea mustard yields as seawater surface temperature continuously has been rising. Especially if the upward trend in seawater surface temperature since 2005 will be maintained in future, sea mustard yield is expected to decrease by 2.6% per year.

• Transactions of Materials Processing
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• v.8 no.2
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• pp.208-215
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• 1999

To increase rolling yields by minimizing trimming losses of hot-rolled plate, optimization logic for the edger model has been developed. The logic to determine optimum edging amount model has been formulated on the basis of actual production rolling data. In case of broadside rolling, the fish tail shape at the sides of plate was better for reducing the crop loss and this could be achieved when the edging amount of broadside rolling was increased. At a given broadside rolling ratio, methodology to determine optimum edging amount for the finish rolling which could minimize the width deviation of plate were systematically derived. Therefore, for a given broadside rolling condition and the permissible tolerance in width deviation of plate, it was possible to optimize the edging amount in finish rolling to maximize rolling yields. The application of optimization logic in this study increased rolling yields from approximately 10% to 30% at various longitudinal eding raitos.

• Journal of Biosystems Engineering
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• v.30 no.6 s.113
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• pp.360-365
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• 2005

Precision agriculture attempts to improve cropping efficiency by variable application of crop treatments such as fertilizers and pesticides, within field on a point-by-point basis. Therefore, a more complete understanding of the relationships between yield and soil properties is of critical importance in precision agriculture. In this study, the functional relationships between measured soil properties and rice yield were investigated. A supervised back-propagation neural network model was employed to relate soil chemical properties and rice yields on a point-by point basis, within individual site-years. As a results, a positive correlation was found between practical yields and predicted yields in 1999, 2000, 2001, and 2002 are 0.916, 0.879, 0.800 and 0.789, respectively. The results showed that significant overfitting for yields with only the soil chemical properties occurred so that more of environmental factors, such as climatological data, variety, cultivation method etc., would be required to predict the yield more accurately.

• Journal of Ginseng Research
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• v.9 no.2
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• pp.170-178
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• 1985

Korean red ginseng tails was extracted with solutions having various ethanol concentration at the temperature range of 70-100 $^{\circ}C$. Extraction was carried out for 1-5 times of 8 hours at given temperature. The results obtained on physicochemical properties of yields, saponins, sugars, minerals, color and viscosity were analyzed statistically to find the correlation with extracting conditions. A very high positive correlation was found between extraction time and cumulative values of yields of chemical components. Increase in ethanol concentration affected negatively on viscosity, absorbencies and yields of soluble solids and minerals. Some of the properties also showed a high correlation with temperature increase. Equations were also derived from the significant results on correlation analysis.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.6
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• pp.775-781
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• 2016

A single trait linear mixed random regression test-day model was applied for the first time for analyzing the first lactation monthly test-day milk yield records in Karan Fries cattle. The test-day milk yield data was modeled using a random regression model (RRM) considering different order of Legendre polynomial for the additive genetic effect (4th order) and the permanent environmental effect (5th order). Data pertaining to 1,583 lactation records spread over a period of 30 years were recorded and analyzed in the study. The variance component, heritability and genetic correlations among test-day milk yields were estimated using RRM. RRM heritability estimates of test-day milk yield varied from 0.11 to 0.22 in different test-day records. The estimates of genetic correlations between different test-day milk yields ranged 0.01 (test-day 1 [TD-1] and TD-11) to 0.99 (TD-4 and TD-5). The magnitudes of genetic correlations between test-day milk yields decreased as the interval between test-days increased and adjacent test-day had higher correlations. Additive genetic and permanent environment variances were higher for test-day milk yields at both ends of lactation. The residual variance was observed to be lower than the permanent environment variance for all the test-day milk yields.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.3
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• pp.190-198
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• 1996

This experiment was conducted to evaluate the forage yield and quality potential of Festulolium braunii (Festuca pratensis Huds. $\times$ Lolium multiflotum Lam) as forage source in Korea. The experimental design was a split plot design with four replications from Feb. 1994 to Jan. 1996 at Hohenheim uniwrsity. Main plots were three forage species {Fesruca pratensis(Cosmos), Lolium mult~~orum(Lemtal) and Festulolium braunii(Pau1ita)) and subplots were three N levels (150,300 and 450kgha). No differences in dry matter(DM) yields were noted between Festulolium braunii and Lolium multj7orum, but DM yields for Festulolium braunii was 138 more than for Fesruca prafensis(P<0.01 ). Total DM yields over all species increased linearly with increasing N levels. The peak of DM yields over 2 years mean at 450kglha N levels were higher for Lolium mulriJotum(l5,724kg) than for Festulolium braunii(14,730kg) and for Festuca pratensis(l3,68 l kg) (P<0.01). OMD, ME, NEL and other minerals of Fesrulolium braunii were slightly higher and CP, Ca and Mg slightly lower than thsoe of Fesruca pratensis, but CP, OMD, NEL and minerals were absolutly higher for Fesrulolium braunii than for Lolium mulriflorum(P<0.01). It appears that Festulolium braunii has higher potential for improvement of the forage quality than Fesruca prarensis or Lolium rnulrijlorum. The content of CP, CF and minerals were increased, wherease OMD, ME and NEL were decreased in all species with increasing N levels. Yields of CP, DOM and NEL over 2 yean mean were increased in all species with increasing N levels. CP, DOM and NEL yields of Festulolium braunii were higher than those of Lolium multiflorum or Festuca pratensis(P

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.8
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• pp.1136-1141
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• 2011

Effect of dietary essential oils on growth, feed utilization and meat yields of white leg shrimp L. vannamei was investigated. White shrimp fry weighing 0.62 g were kept in one of 12 tanks (75 head/500 L holding tank) in a closed recirculation system. Four experimental diets, a commercial diet (control), phytoncide oil (PO), oregano oil (OO) and fermented garlic liquid (GL) were fed for 16 weeks. The mean water quality values for the whole experimental period were $27.8{\pm}1^{\circ}C$, $7.6{\pm}0.3$, $15.5{\pm}0.3$ g/L and $6.1{\pm}0.3$ mg/L for water temperature, pH, salinity and dissolved oxygen, respectively. At the end of the trial, 10 shrimp per tank were randomly sampled and meat yields (%) were evaluated after peeling the shell and removing the head. After a 16 week feeding trial, final weight of shrimp ranged from 21.9 g to 23.6 g. Feed conversion was not significantly different among groups (p>0.05), which was the lowest (1.95) in the control and highest (2.30) in the PO. Specific growth rate was also not significantly different (p>0.05) and ranged from 3.18% to 3.25%. Average daily gain of 0.2 g was obtained in all treatments. Mortality varied from 35.1% for control to 44.9% for OO. Meat yields maintained constant at 52.1% for control to 53.0% for PO. The study suggested that natural essential oils could not exert any improvement in growth performance, mortality and meat yields of white leg shrimp.