• Korean Journal of Food Science and Technology
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• v.13 no.4
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• pp.334-339
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• 1981

Surface color, water extract color and soluble solids of the roasted barley resulted from the various roasting conditions were determined to establish the optimum roasting conditions. The correlation coefficients between the surface color of the roasted barley and its ground was in the range from 0.957 to 0.994, and which showed the internal color being well represented that of surface of the roasted grain. The degree of roasting was determined maim by the roasting temperature, rather than by the total heat energy input during roasting. The maximum yield of the water soluble solids was 68% and obtained from the barley roasted at $232^{\circ}C$ for 25 minutes. The readings of Y-value of the roasted whole barley was a good index to judge and control the degree of roasting.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.4
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• pp.386-391
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• 1988

Five barley crosses and their progenies (F$_2$, F$_3$, and F$_4$) were evaluated the potentiality of hybrid populations to segregate superior yielders in later generation. Four characters used for evaluation were number of spike, number of grain, spike weight and grain weight per plant. Superiority value (Y) of number of spike was best in SB76588${\times}$SB72648 and average of superior plants in F$_4$, was excellent in this cross. Milyang 6${\times}$Suwon 203 showed high Y value and average of F$_4$ superior plants in the number of grain. Spike weight showed the highest Y value and excellent averages of superior plant in Milyang 6${\times}$Suwon 203. Superiority value of grain weight per plant coincided with average of F$_4$ superior plants in 3 crosses and SB76588${\times}$SB72648 was the best among the crosses.

• Journal of The Geomorphological Association of Korea
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• v.19 no.4
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• pp.157-168
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• 2012

The Eonyang section is located at the confluent area of Samdong River to Taehwa River in Sinhwa-ri, Samnam-myeon, Ulju-gun, Ulsan-si, Korea. Physical analyses such as the OSL age dating, magnetic susceptibility and grain size analysis were performed. Coarse grains in the upper section were deposited by the aeolian processes from the local sources and the grains in the lower section by the fluvial processes. The Eonyang section shows the large differences such as the irregularity in the variations of magnetic susceptibility, large deviations in the Y values and very poor sorting values from the loess sediments in Bongdong, Geochang and Daecheon in Korea. These characteristics in the Eonyang section suggest the multi-source areas such as the Chinese Loess Plateau and nearby floodplain or the influences by the other processes. The loess sediments of Eonyang section were formed during the period from the late MIS 3 to MIS 2.

• Applied Chemistry for Engineering
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• v.8 no.6
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• pp.954-959
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• 1997

The solid solutions of the $Sr_{1-X}M_XFeO_{3-y}$ (x=0.1, 0.2, 0.3, 0.4, 0.5, M=Ca) system having perovskite structures were prepared in air by heat treatment at 1473 K for 18hr. X-ray diffraction assigns cubic system for all the samples and shows that the lattice volume of each system decreases with increasing x value until x=0.3, but increases abruptly from x=0.4. The mole fractions of $Fe^{4+}$ ion($\tau$ value), the amounts of oxygen vacancy (y value) and finally nonstoichiometric chemical formulas for each composition were determined from Mohr salt analysis. TG/DTA thermal analysis (temperature range: 300~1173K) exhibits that 3-y values of the samples having x=0.1 and 0.2, decrease with temperature and increase almost reversibly with decreasing temperature. The samples of $x{\geq}0.3$, however, didn't show the reversible weight change and the 3-y values of them were nearly 2.5 in cooling process. Conductivities of each sample were varied within the semiconductivity range at relatively low temperature. And the conductivity at constant temperature decreases steadily with x value. The conduction mechanism of this ferrite system may be proposed as a hopping model of conducting electrons between the mixed valence states. At high temperature semiconductivity of each sample changed into metallic property.

• Journal of the Korean Chemical Society
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• v.31 no.1
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• pp.25-30
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• 1987

Solvolysis of tert-butyl halides and 1-adamantyl tosylate in methanol-acetone mixtures and solvolysis of tert-butyl bromide in methanol-chloroform mixtures have been studied. Solvent ionizing power of methanol-acetone mixtures were calculated by the Grunwald-Winstein equation and discussed the Y value variation caused by substrate changes. Y values based on 1-adamantyl tosylate is superion to others since it varies in wide range for methanol-acetone mixtures. It was found that the order of electrophilic assistance to leaving group is OTs > Cl > Br > I.

• Journal of the Korean Chemical Society
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• v.37 no.11
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• pp.923-928
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• 1993

The series of solid solutions in the $Sr_{1+x}Ho_{1-x}FeO_{4-y}$ (x = 0.00, 0.25, 0.50, 0.75 and 1.00) systems with $K_2NiF_4$ type structure have been prepared at 1550$^{\circ}$C under an atmospheric air pressure. The X-ray powder diffraction spectra of these samples assign that the crystallographic phases are tetragonal system over the whole x range. The lattice volume was increased with increasing the substitution amount of the $Sr^{2+}$ ion. The mole ratio of the $Fe^{4+}$ ion to total iron ions or ${\tau}$ value has been determined by Mohr salt titration of the sample and then the y value was calculated from x and ${\tau}$ values. The ${\tau}$ and y values have been increased with x values. The nonstoichiometric chemical formula are formulated from the general formula of $Sr_{1+x}Ho_{1-x}Fe^3_{1-}\;^+_{\tau}Fe_{\tau}^{4+}O_{4-y}$ replaced by x,${\tau}$ and y values. Mossbauer spectra show the mixed valence state and coordination state of $Fe^{3+}\;and\;Fe^{4+}$ ions. It is found out that the magnetic property of the samples is paramagnetic at room temperature. Electrical conductivity varied within the semiconductivity range of 1.0 to 1 ${\times}\;10^{-9}{\Omega}^{-1}cm^{-1}$. Activation energy of the electrical conductivity was decreased with the $\tau$ value. The conduction mechanism should be explained by the hopping model of the conduction electrons between the valence states of $Fe^{3+}\;and\;Fe^{4+}$ ions.

• Journal of Sericultural and Entomological Science
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• v.48 no.2
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• pp.46-55
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• 2006

In this thesis, we took some stalks, flowers, and leaves of the Serratuls coronate var. insularis which are able to propagate as mass n our wild to extract the dyeing solution, and cotton and silk were dyed using them in many different conditions. Silk was dyed darker than cotton. We found there was not a big difference between silk and cotton in the given condition considering 'Y' values vs. dyeing temperature. There was a rapid decreasing of 'Y' values after one to two hours and almost all of dyeing was completed at these times. We found there was a dyeing acceleration at the higher dyeing density and the lower 'Y' value. If the density was low, dyeing attachment was reduced by dyeing ability via the density of liquid in both plants. Silk was affected higher by mordant dyes in both plants. Fe and Cu had an effect by mordant dyes slightly an Serratuls coronate var. insularis.

• Journal of Sericultural and Entomological Science
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• v.47 no.2
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• pp.78-87
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• 2005

In this thesis, we took some stalks, flowers, and leaves of the Hypericum ascyron L. which are able to propagate as mass in our wild to extract the dyeing solution, and cotton and silk were dyed using them in many different conditions. Silk was dyed darker than cotton with increasing the pH density. Silk was dyed darkest among Hypericum ascyron if pH was neutral. We found there was not a big difference between silk and cotton in the given condition considering 'Y' values vs. dyeing temperature. However cotton was dyed darker in hypericum ascyron. There was a rapid decreasing of 'Y' values after one to two hours and almost all of dyeing was completed at these times. We found there was a dyeing acceleration at the higher dyeing density and the lower 'Y' value. If the density was low, dyeing attachment was reduced by dyeing ability via the density of liquid in this plants. Silk was affected higher by mordant dyes in this plants. Fe and Cu had no effect on Hypericum ascyron.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.11
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• pp.1053-1060
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• 2013

The purpose of this study is to estimate the packing friction of power-operated valve in nuclear power plants. The roll of packing in valve is preventing leakage through stem. Packing friction is highly depend on gland nut tightness which means higher reliability in sealing is lower operability. For the estimation of friction, we used statistical analysis and experimental analysis. In experimental approach, we have performed packing fY test and applied it to valve field test. In statistical approach, we have used 10 years DB of safety-related valve in nuclear power plant and analyzed packing friction based on confidence interval of sample. The comparison of two results shows that statistical analysis for packing friction are more accurate than fY analysis even though both approach have error compared to measured value but we confirmed that statistical approach is proper way to estimate packing friction.

• School Mathematics
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• v.14 no.3
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• pp.275-296
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• 2012

This study investigated elementary school students' understanding of basic functional relationships. It analyzed the written responses from a total of 2087 students of second, fourth, and sixth graders using tests that examined their understanding of five types of functional relationships. The results of this study showed that students tended to be more successful as their grades went up with regard to all the problem types. There were statistically differences among the three grade levels. Even lower graders were quite successful in dealing with additive relation, direct proportion, and inverse proportion. However the items dealing with square relation and linear relation were difficult even to sixth graders. It was common that students were good at completing the table by looking for a pattern from the given numbers but that they had difficulties in anticipating the value of 'y' when the value of 'x' is given either as a big number or as a symbol. Given these results, this paper includes issues and implications on how to foster functional thinking ability at the elementary school.