• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.2
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• pp.114-120
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• 2006

The basic effects of hydrogen addition for engine performance and emission were investigated in single cylinder research engine. Seven commercial injectors were tested to choose a suitable injector for hydrogen injection prior to its engine implementation. The hydrogen fuel leakage and flow rate were evaluated for each injector and KN3-1(Keihin, CO.) showed the best performance for hydrogen fuel. At the higher excess air ratio(${\lambda}=1.7$, 2.0), the better combustion stability was found with hydrogen addition even though its effect was small at lower excess air ratio (${\lambda}=1.0$, 1.3). Stable operation of the engine was even guaranteed at ${\lambda}=2.0$, if the amount of hydrogen gas was near 15% of total energy. In the lean region, ${\lambda}>1.3$, thermal efficiency was improved slightly while it was not clearly observed at ${\lambda}=1.0$, 1.3. It is considered that, in some cases, high temperature environment due to hydrogen combustion caused further heat loss to surroundings. Except for ${\lambda}=1.0$, with larger amount of hydrogen addition, CO was reduced drastically but it was emitted more at the leaner region. Nitric oxides(NOx) was increased a little more with hydrogen addition at ${\lambda}=1.0$, 1.3. However, at ${\lambda}>1.3$ its relative amount of emission was low. In addition, the amount of NOx was continuously decreased with hydrogen addition, but, at ${\lambda}=2.0$ the amount of NOx was lowered to 1/100 of that of ${\lambda}=1.0$. THC emission was significantly increased as air/fuel ratio was raised to leaner region due to misfire and partial burn.

• Journal of Biosystems Engineering
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• v.8 no.1
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• pp.38-46
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• 1983

This study was carried out to investigate the possibility of improving the performance of a kerosene engine with water addition. The engine used in this study was a single-cylinder, four-cycle kerosene engine with the compression ratio of 4.5. Water could be successfully added into the inlet manifold by an extra carburetor for the volumetric ratios of 5, 10, 20, and 30 percents. Variable speed tests at wide-open throttle were performed for five speed levels in the range of 1,000 to 2,200rpm for each fuel type. Volumetric efficiency and brake specific fuel consumption were determined, and brake thermal efficiency based on the lower heats of combustion of kerosene was calculated. To examine variation in fuel consumption, CO concentration, and cooling water temperature, part load tests were also performed. The results obtained are summarized as follow. (1) Brake torque increased almost in proportion to volumetric efficiency. But the ratio of increase in torque was greater than that of volumetric efficiency. Mean torque over the speed range of 1,000 to 2,200rpm increased 1, 3, 7, and 2 percents for 5, 10, 20, and 30 percents water addition, respectively. The increase in brake torque with water addition was greater at lower speeds. (2) Mean brake specific fuel consumption over the speed range of 1,000 to 2,200rpm decreased 1, 2, 3, and 3 percents for 5, 10, 20, and 30 percents water addition, respectively. (3) Mean temperature of cooling water over the speed range of 1,000 to 2,200rpm decreased 2, 4, 8, and 12 percents for 5, 10, 20, and 30 percents water addition, respectively. (4) The effects of decreasing CO concentration in the exhaust emissions with water addition were significant. At the speed range of 1,000 to 2,200rpm, CO concentration in the exhaust emissions decreased 2, 10, 23, percents for 5, 10, and 20 percents water addition, respectively. (5) Deposits were not discovered in the combustion chamber during the experiment. However, a little rust was formed in the water-supply carburetor.

• Applied Chemistry for Engineering
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• v.19 no.2
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• pp.242-248
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• 2008

The iron incorporation method according to addition steps during the synthesis of iron incorporated MCM-41 was examined systematically. Iron addition during pH adjustment was more effective than the other addition steps which were addition to template agent solution or addition after mixing of template agent and sodium silicate solution. In case of iron addition after extraction of template agent from as-synthesized silica MCM-41, most of the iron was on the surface of pores not the frame work structure. Although the amount of iron addition was increased, there was a limit to the amount of iron incorporated into framework structure of MCM-41. The synthesized FeMCM-41 catalyst showed catalytic activities for propylene oxidation. Otherwise, there might be no attractive differences of catalytic activity among the addition steps of iron.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.6
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• pp.894-902
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• 2007

This study was performed to observe the quality characteristics of Eunhakong dasik and Small Black Soybean dasik prepared with different addition rates of chlorella powder. For the Hunter's color values, the $L^*,\;a^*,\;and\;b^*$ values of both dasiks decreased with the addition of chlorella powder. The cohesiveness and gumminess of both dasiks were not dependant on the chlorella powder additions. However, the hardness of the Eunhakong dasik with 8% chlorella powder increased. The springiness and brittleness of the Eunhakong dasik had a tendency to decrease as the addition rate of the chlorella powder increased. In terms of sensory quality, both the dasiks were improved by the addition of 4% chlorella powder. Therefore, in subsequent examinations, the chemical characteristics of both dasiks were determined for the 4% addition of chlorella powder. The moisture and crude lipid contents of both dasiks were not influenced by the addition of chlorella powder. Carbohydrate content was highest in the Eunhakong dasik with 0% chlorella powder, and in the Small Black Soybean dasik with 4% chlorella powder. Conversely, crude protein content was highest in the Eunhakong dasik with 4% chlorella powder, and in the Small Black Soybean dasik with 0% chlorella powder. The crude lipid content of the Small Black Soybean dasik with 4% chlorella powder was lower than that of the control without chlorella powder. For mineral content, the K content of both dasiks was not influenced by the addition of chlorella powder. The Ca, Mg, and P contents of both dasiks with 4% chlorella powder, respectively, were lower than those of the dasik with 0% chlorella powder. Finally, the total amino acid content of the Eunhakong dasik tended to decrease, while that of the Small Black Soybean dasik incrased, with the 4% addition of chlorella powder.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.5
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• pp.631-640
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• 2014

In this study, manufactured a cream soup by varying addition of Hericium erinaceus and decided its recipe, and conducted particle size analysis, calorimetry, sensory test for investigating physicochemical characteristics and quality characteristics (salinity, sugar content, color value, pH, viscosity), antioxidant activities of soup, and mechanical sensory test for objectivity. This study found that moisture content in Hericium erinaceus powder was 6.16%, crude protein 26.87%, crude fat 4.62% and crude ash was 10.75% respectively. No significant differences were found in salinity, sugar content, pH according to addition of Hericium erinaceus. As for color value of cream soup manufactured by adding Hericium erinaceus, L value decreased with increase in addition of Hericium erinaceus, whereas a value and b value increased. The more the addition of Hericium erinaceus, the higher the viscosity, which increases concentration of soup. As result of analysis on antioxidant activities of Hericium erinaceus cream soup, antioxidant activities increased with increase in addition of Hericium erinaceus. Particle size analysis showed results similar to that of viscometry, which means that the smaller the particle size, the higher the viscosity, whereas viscosity lowered vice versa. Calorie of cream soup showed no significant difference notwithstanding the amount of addition. As a result of sensory test, S5 with 5% of Hericium erinaceus powder was highest rated in color, flavor, taste, umami taste and overall preference. As a result of mechanical sensory test, umami taste increased with increase in addition of Hericium erinaceus powder, whereas bitterness taste lowered significantly (p<0.05) with addition of Hericium erinaceus. As for salty taste, both control group and experimental group that added Hericium erinaceus powder showed no significant difference. Accordingly, experimental group with 5% of Hericium erinaceus powder was proved to be the most desirable.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.5
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• pp.529-539
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• 2017

The aim of this work was to make acorn bread containing natural antioxidants as healthy food. The amylographic characteristics, loaf volume, color, texture, and subjective preference of the acorn bread containing 5~25% of acorn flour were measured during storage at room temperature and in a freezer. The results were as follows: The loaf volume decreased with increasing the addition of acorn flour from 5% to 25%. The onset gelatinization temperature and the value at the peak point of the bread decreased according to the amount of acorn flour added. L-value decreased with the increase of acorn flour contents, but the a- and b- values increased. During the storage period at room temperature, the L, a, and b- value decreased, whereas in the freezer, the L-value decreased except for the bread containing 5~11% acorn flour. In sensory evaluation, color and taste achieved high scores at 18% addition, but low scores at 25% addition. The bitter aftertaste showed low scores according to the addition of acorn flour. The softness and chewiness decreased, but the overall acceptance increased according to the addition of acorn flour except for the bread added with 25% acorn flour. The textural measurements showed that the hardness, springiness, gumminess, and brittleness increased significantly during the storage periods. The cohesiveness, gumminess, and brittleness in room temperature storage decreased with the increase of acorn flour contents. In freezer storage, the addition of acorn flour resulted in the increase of hardness, springiness, gumminess, and brittleness during storage periods. On the other hands, the cohesiveness decreased with the addition of acorn flour. Moreover the addition of acorn flour increased significantly the hardness, gumminess, and brittleness during storage periods. As a result, the bread containing acorn flour showed reasonable textural properties during storage periods.

• Advances in materials Research
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• v.5 no.2
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• pp.93-105
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• 2016

KNN-based ceramics modified with small amounts of $Bi_4Zr_3O_{12}$ (BiZ) has been synthesized using high-throughput experimentation (HTE). The results from X-ray diffraction show that for samples with base composition $(K_{0.5}Na_{0.5})NbO_3$ (KNN), the phase present changes from orthorhombic to pseudo-cubic with more than 0.2 mol% BiZ addition; for samples with base composition $(K_{0.48}Na_{0.48}Li_{0.04})(Nb_{0.9}Ta_{0.1})O_3$ (KNNLT), the phase present changes from a mixture of orthorhombic and tetragonal symmetry to pseudo-cubic with more than 0.4 mol % while for samples with base composition $(K_{0.48}Na_{0.48}Li_{0.04})(Nb_{0.86}Ta_{0.1}Sb_{0.04})O_3$ (KNNLST), the phase present is tetragonal with <0.3 mol% BiZ addition and transforms to pseudo-cubic with more dopant addition. The microstructures of the samples show that addition of BiZ decreases the average grain size and increases the volume of pores at the grain boundaries. The values of dielectric constant for KNN and KNNLT compositions increase slightly with BiZ addition while that for KNNLST decreases gradually with BiZ addition. The dielectric loss values are between 0.02 and 0.04 for KNNLT and KNNLST compositions while they are ~ 0.05 for KNN samples. The resistivity values increases with BiZ addition and values in the range of $10^{10}{\Omega}cm$ and $10^{12}{\Omega}cm$ are obtained. The piezoelectric charge coefficient ($d{^*}_{33}$) is highest for KNNLST samples and decreases gradually from ~400 pm/V to ~100 pm/V with BiZ addition.

• The Korean Journal of Food And Nutrition
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• v.30 no.5
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• pp.916-922
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• 2017

This study was conducted to investigate changes in organoleptic properties and taste components including free sugar, organic acid and free amino acid with addition of walnut. Changes in total nitrogen were insignificantly different with addition of walnut. Amino type nitrogen content was decreased in proportion to supplemental level of walnut. Content of organic acids, of which three kinds were detected, such as citric acid, malic acid and lactic acid increased more than two times with addition of walnut. Contents of free sugar and amino acid were decreased with addition of walnut. The proportion of essential amino acid was 40.6~41.4 percent. Glutamic acid in total amino acid was increased in proportion with addition of walnut. The highest sensory evaluation score was recorded in soy sauce with addition of 2 percent walnut. Together, it was expected that 2 percent addition of walnut to soy sauce has a positive effect on the taste of soy sauce.

• Journal of Elementary Mathematics Education in Korea
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• v.22 no.4
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• pp.331-368
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• 2018

This study is derived from a student who can add without knowing the addition principle. To understand where the student's response come from, we came to analyse the curriculum contents of natural numbers, decimals and fractions addition principle. At the same time, we surveyed two different school of forty six sixth grade participants with questionnaires to determine whether it is a problem of the student or an universal one. As a result, we found that there is a room for improvement in the addition and connections of addition. We propose appropriate instructional method regarding connections of addition and addition principle of natural numbers, decimals and fractions. The conclude there is a close relation and differences among the principles of natural numbers, decimals and fractions in the proposed instructional method. Therefore, we need to consider and instruct the differences of the number expansion.

• The Korean Journal of Food And Nutrition
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• v.31 no.6
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• pp.926-932
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• 2018

This research was conducted to investigate the changes in quality characteristics of cheonggukjang fermented with the addition of hazelnut (10, 20, 30 and 40%) including; water content, pH, hydrophilic and lipophilic substances, color, viscosity and angiotensin converting enzyme inhibition activity. There was no significant change in pH with the addition of hazelnut. The water content significantly decreased with the addition of hazelnut. Hazelnut was also found to brighten the color of cheonggukjang. L-value and b-value increased with the addition of cheonggjuang. There was an insignificant change in the a-value. There was a slight decrease in the content of hydrophilic with addition of hazelnuts. Where there was more than 20% addition of hazelnut to soybean, the viscous substance content in cheonggukjang decreased significantly. Angiotensin converting enzyme inhibitory activity increased proportionally to the amount of hazelnut added. It was identified that the addition of 40% of hazelnut made its angiotensin converting enzyme inhibitory activity 10% point higher than that of control. These results suggests that the addition of hazelnut makes it possible to produce cheongkukjang of excellent angiotensin converting enzyme inhibitory activity.