• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.325-325
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• 2007

The perovskites in the $LaAlO_3-BaZrO_3$ system (i.e., $(1-x)LaAlO_3-xBaZrO_3$ were fabricated by a solid state reaction and their dielectric properties were investigated. For the compositions of x=0.1~0.9, the mixture of $LaAlO_3$ with a rhombohedral structure and $BaZrO_3$ with a cubic was observed when the sintering was conducted at $1500^{\circ}C$, indicating that the solubility of constituent elements was very low and a narrow solid solution region might exist. The large difference of ionic radii between $La^{3+}$ ion (0.136nm, C.N.=12) and $Ba^{2+}$ ion (0.161nm) or $Al^{3+}$ ion (0.0535nm, C.N.=6) and $Zr^{4+}$ ion (0.072nm) might hinder the mutual substitution. Within the compositions of x=0~0.7, the dielectric constant of the mixture increased with the amount of $BaZrO_3$, i.e., x value, which was in good agreement with the logarithmic mixing rule (In $_{r,i}={\Sigma}v_iln\;_{r,i}$). The increase in $BaZrO_3$ doping decreased $Q{\times}f$ value significantly due to the low $Q{\times}f$ value of $BaZrO_3$ itself, a poor microstructure of the mixture with an increased grain boundary area per volume, and defects in the cation and oxygen sub-lattices which were respectively caused by the evaporation of barium during the sintering process and the substitution of Ba on La-site or Al on Zr-site.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.1
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• pp.44-49
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• 2019

The purpose of this study is to analyze the fundamental characteristics of concrete with the change of reject ash(Reject ash=Rj) in the mixed aggregate where single grain aggregate of different grain size and aggregate of opposite grain size are mixed together, to analyze the possibility of a mixed aggregate system that premixes at an aggregate manufacturing plant and delivers it as one aggregate. As a result of the experimental study, it was found that the grain size regulation is satisfied if the mixed aggregate(CSb+SS) is substituted for about 5% of Rj. In the case of the fluidity slump, slump flow and air volume, it was found that they decrease as the substitution ratio of Rj increases, while the compressive strength increases as the substitution ratio of Rj increases. Therefore, it is analyzed that it would contribute greatly to an improvement of quality such as improvement of compressive strength if adequate fluidity and air quantity are secured by the water reducing agent and AE agent while premixing the Rj, which is disposed of by landfill, with about 5% of the mixed aggregate.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.1
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• pp.87-94
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• 2008

In this study, a nanatural fermentation starter formulation was developed for manufacturing bread products by substituting baker's yeast with naturally fermented raisin extract and sourdough. Four experimental groups containing 2.5, 5.0, 7.5, 10% naturally fermented raisin extract per 2,000 g of flour were compared based on quality characteristics, including the fermentation power on dough expansion, specific volume, baking loss, water activity, color, textural characteristics, and internal surface appearance. The activities of the naturally fermented raisin extract were examined in terms of pH changes, total titratable acidity, brix, and viable yeast counts. The raisin extract, which was cultured for 7 days at 30$^{\circ}C$, smelled of alcohol and produced $CO_2$. Yeast were also found in the extract after separation. As the incubation time of the raisin extract and sourdough increased, pH decreased, while total titratable acidity increased. The brix of the raisin extract increased until the $2^{nd}$ day of fermentation, and viable yeast counts increased until the $5^{th}$ day however, these gradually decreased by the $7^{th}$ day. The fermenting power on dough expansion increased in the bread with increasing incubation time. The bread samples containing 7.5% and 10% raisin extract had significantly higher specific volumes than the other samples. Baking loss was minimal with the 2.5% extract substitution. In analyzing the crumb, water activity, redness, and yellowness were highest in the 10.0% raisin extract bread samples, and lightness was maximal in the 5.0% group. In terms of textural characteristics, hardness was lowest with the 2.5% extract substitution. Gumminess, springiness, and chewiness were not significantly different among the bread samples. Cohesiveness was highest at the 7.5% extract substitution level, and resilience was lowest at the 10% level. In conclusion, based on the results, a natural fermentation starter formulated with 2.5% naturally fermented raisin extract (1 part raisins and 1.5 parts water) and 70% sourdough (1 part rye flour and 1 part water) has high potential as a baker's yeast substitute for making naturally fermented bread.

• The Korean Journal of Food And Nutrition
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• v.24 no.4
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• pp.567-576
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• 2011

A study was undertaken to examine the antioxidative activity and the quality attributes of broccoli stem powder pound cakes. Broccoli stem powder was added to the batter at a ratio of 5, 10 and 15% respectively. The antioxidant activity was estimated by DPPH free radical scavenging activity, the total phenolic compounds content and flavonoid content in Broccoli stem powder and pounds cakes. Antioxidative activity was highly correlated with the total phenolic and total flavonoids contents of broccoli stem pound cakes respectively($r$=0.937, $r$=0.981). The effect of cake improver on quality characteristics of cake broccoli stem powder and pound cakes were estimated in terms of the specific load volume, hardness, hunter value of crumb and crust and sensory quality of cakes. The specific volume were increased significantly with increasing substitution level of cake improver and broccoli stem powder($p$ <0.01). The lightness were significantly decreased with increases in broccoli stem powder of pound cake crust and crumb($p$ <0.01, $p$ <0.01). The hardness, chewiness and gumminess and cohesiveness were tended to reduce in both of powder. The consumer acceptability score for 5~10% broccoli stem pound cakes ranked significantly($p$ <0.01) higher than those of the other groups in taste, flavor and overall preference. This results showed that cake improver & broccoli stem powder are a good ingredient to increase consumer acceptability and the healthy.

• Culinary science and hospitality research
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• v.22 no.3
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• pp.1-10
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• 2016

The study was conducted to evaluate the effect of substitution of flour with Suaeda asparagoides(at the levels of 0%, 2%, 4%, and 6%) on the characteristics of sponge cake. The specific gravity of batter increased significantly as the content of Suaeda asparagoides increased. The specific volume and baking loss rate of cake decreased significantly as the content of Suaeda asparagoides increased. The volume and weight of batter increased significantly as the content of Suaeda asparagoides increased. Texture analysis showed that the control had the lowest hardness and highest springiness. According to sensory evaluation, the experiment groups scored higher points in texture acceptance than the control. Above all, the 2~4% samples scored the highest points in aroma, taste, appearance, and overall acceptance.

• Korean journal of food and cookery science
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• v.22 no.1 s.91
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• pp.62-68
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• 2006

This study evaluated the effect of the substitution of flour with Angelica plant(Bakluncho) powder on the characteristics of batter cake and cookies. The specific volume of batter cake was increased significantly with increasing content of Angelica plant powder, but hardness was decreased slightly. The specific volume of cookies didn't show significant difference, and the width detennined by the water content in the dough was decreased with increasing content of Angelica plant powder. The L value in the crust and crumbs of the cake was significantly the largest value in the control group. The a and b values were the highest in the 5% substituted sample group. The L, a and b values of the cookies also showed the same pattern. According to the sensory evaluation of cakes and cookies, the scores of flavor, color, and texture were raised by the addition of Angelica plant powder. The acceptance tests of cakes and cookies showed a higher overall acceptability than those of the 1% and 3% substituted samples.

• Korean journal of food and cookery science
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• v.23 no.4 s.100
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• pp.530-536
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• 2007

In this study, rice flour sponge cakes were prepared by replacing 50% of the sucrose with oligosaccharides. Isomaltooligosaccharide and fructooligosaccharide were used as the oligosaccharides. The effects of oligosaccharides on the physical, textural and sensory properties of the cakes were then examined. The oligosaccharides increased batter viscosity and decreased batter specific gravity and baking loss. The moisture content, specific loaf volume and loaf volume index of the cake increased by replacing 50% of the sucrose with oligosaccharides. Internal and exterior color determinations showed that the 'L' value of the sponge cake with oligosaccharides was lower than that of the control, indicating a darker crust and crumb with the oligosaccharide substitution. Decreases in textual hardness, chewiness, and brittleness occurred with the oligosaccharides. Sensory panels perceived that the oilgosaccharide darkened the crust of the rice flour sponge cake and the panelists rated the cakes with the oilgosaccharide substitutions as sweeter, softer and more moist. The rice flour sponge cakes with isomaltooligosaccharides had a significantly higher acceptability then the others.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.577-585
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• 2013

This study investigated the physicochemical and sensory characteristics of rice pound cake prepared with various amounts of blueberry powder. The weight of rice pound cakes with additions of 2~8% blueberry powder increased from 418.58 to 420.50 g. The volume and specific loaf volume of rice pound cakes prepared by adding blueberry powder were lower than those of the control. The baking loss rate for the control was 7.72% and that of rice pound cakes prepared by adding blueberry powder decreased by 6.98~6.56%. The moisture contents of rice pound cakes added with blueberry powder were higher than the control. The pH levels for rice pound cakes prepared with blueberry powder ranged between 6.47 and 7.58 and that of the control was 8.11. The microstructural observation by scanning electron microscopy (SEM) showed well developed air cells of control. DPPH radical scavenging activity of the control group was 13.6%, whereas pound cakes prepared by adding blueberry powder ranged from 35.2~78.8%. The "a" value of redness was increased, but L and b value were decreased significantly by additions of blueberry powder. The full textural properties of rice pound cakes were being significantly increased by additions of blueberry powder. Sensory evaluation scores in terms of appearance, flavor, taste, texture and overall preference for pound cakes showed that 4~6% of substituted sample groups were higher than those of others. The results of this study suggest that additions of 4~6% blueberry powder was the best substitution ratio for rice pound cakes.

• Korean journal of food and cookery science
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• v.30 no.3
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• pp.239-248
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• 2014

This study investigated the physicochemical and sensory characteristics of pound cake prepared with various amounts of dropwort powder. According to the results, the specific gravity of batter prepared with dropwort powder was increased, whereas the pH of batter was decreased significantly with the addition of dropwort powder. Furthermore, the weight of the pound cake prepared by adding 8% dropwort powder had the lowest among all samples. The volume and specific loaf volume of pound cakes prepared by adding dropwort powder were higher than those of the control. The baking loss rate of the control was 5.45% and that of pound cakes prepared by adding dropwort powder was 5.08~7.08%. In addition, the moisture content of pound cakes was found to increase with an increased in the amount of dropwort powder, whereas the pH of pound cakes was found to decrease with an increase in the dropwort powder content. The DPPH radical scavenging activity of the control group was 23.58%, whereas that of pound cakes prepared by adding dropwort powder ranged from 38.77~77.60%. However, the L, a and b values were decreased significantly by the addition of dropwort powder. The hardness, springiness, chewiness and brittleness of pound cakes were decreased significantly by the addition of dropwort powder. Overall, the sensory evaluation scores in terms of appearance, flavor, taste, texture and overall preference for pound cakes were conveyed to be higher in 4~6% of substituted sample groups than those of others. Hence, the results of this study suggest that addition of 4~6% dropwort powder is the best substitution ratio for pound cakes.

• Membrane Journal
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• v.25 no.2
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• pp.162-170
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• 2015

In this study, gas permeability of polyimide materials having a various amine group was measured and molecular dynamics was used to analyze the dynamic characteristics of the gas molecules in the polyimide by calculating the position and velocity of the gas molecules with change of the time. The gas permeability of polyimide membrane having substitution site which increase free volume in the polymer was increased. However, polyimide with rigid structure showed decreased gas permeability. As a result of analyzing the change in the gas permeation behavior using molecular dynamics simulations, we confirmed that the results show the same tendency with actual measurements of the gas permeability.