• Journal of Korean Tunnelling and Underground Space Association
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• v.26 no.5
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• pp.403-419
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• 2024

Advance rate significantly affects both the construction period and cost in tunnel blasting. As such, there has been persistent research dedicated to the development of innovative blasting technique aimed at enhancing the advance rate. This paper aims to provide fundamental insights into the differences in advance rate and the powder factor between two- and three-free-face blasting, laying the groundwork for the advancement of tunnel blasting techniques. Large-scale cement mortar specimens were fabricated, and blasting tests were conducted for both two- and three-free-face blasting. Experimental findings were then compared with those from numerical simulation. Notably, an increase in the number of free faces, under uniform conditions, significantly improved the advance rate while reducing the powder factor. The outcomes of this study serve as crucial groundwork for devising blasting patterns employing three-free-face blasting, characterized by improved advance rates and minimized powder factors. Consequently, the anticipated outcomes include an overall improvement in tunnel advance rates and a reduction in the number of drilling holes and the amounts of explosives.

• The Korean Journal of Food And Nutrition
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• v.26 no.4
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• pp.759-765
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• 2013

This study investigated the quality characteristics of cookies containing Platycodon grandiflorum powder, which is well known for its various functions and biological activity. Cookie samples were prepared by adding the Platycodon grandiflorum powder at different levels of 0%, 1%, 3% and 5%. In this study, moisture, pH, color, spread factor, hardness and sensory evaluation of cookies were examined. The results showed that the pH and moisture of cookies were decreased when more amount of Platycodon grandiflorum powder was added. Regarding the color of cookies, the L value was decreased when more amount of Platycodon grandiflorum powder was added, where as the a value and b value were increased (p<0.001, p<0.01). The spread factor of cookies generally increased as more amount of Platycodon grandiflorum powder was added, but it was not statistically significant. The hardness of the cookies decreased as more amount of Platycodon grandiflorum powder was added. Cookies containing 1% of Platycodon grandiflorum powder showed the highest scores for overall acceptability, color, taste and texture. Regarding the flavor of cookies, the control showed the highest score, and the score decreased as more amount of Platycodon grandiflorum powder was added.

• Fire Science and Engineering
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• v.32 no.3
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• pp.27-34
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• 2018

A Semi-Incombustible Composite Insulation Board (SICIB) that can be applied to building construction and ships was developed. The SICIBs comprised of pine leaf powder, vermiculite. The incombustibility, semi-incombustibility, and U-factor of the developed SICIBs were measured. The incombustibility of the each SICIB was determined by the proportion of combustible flexible binder and pine leaf powder. SICIB satisfied the incombustibility test without a combustible flexible binder and pine leaf powder. In addition, SICIB with 6% of pine leaf ensured its semi-incombustible performance. A combustible flexible binder or pine leaf powder over 6% failed the fire-resistant performance of SICIB. In addition, SICIBs with incombustible/semi-incombustible finishing and a 200 mm insulating layer (glass wool and sprayed poly urethane foam) met the U-factor of an external wall for buildings described in the Korean building code.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.951-956
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• 2000

Blast furnace slag powder(BFS) is potential hydration material, and that usage is increased the construction. But, the amount of BFS is important factor with the properties of concrete. The determinational method of slag powder experiments by salicylic acid-methyl alcohol solution method. From these results we can determine the amount of slag powder with blaine 4, 000 and 6, 000 in fresh concrete.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.3
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• pp.401-408
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• 2009

The purpose of this study was to investigate the quality characteristics of Maejakgwas prepared with different concentrations of shrimp powder (0, 1, 2, 3, 4%) substituted for flour as a snack food for kindergarteners. The pH of the Maejakgwas dough decreased significantly as the level of shrimp powder increased; however, there were no significant differences in dough values among the test groups. Furthermore, the spread factor values of the groups were found to be inversely proportional to the shrimp powder concentration. Hunter's color L, a and b values decreased significantly as the level of shrimp powder increased. Moreover, the 2~4% shrimp powder groups had increased levels of hardness, cohesiveness, springiness, and brittleness when compared to the control. Finally, an acceptance test, the Maejakgwas sample containing 3% shrimp powder received the highest scores.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.4
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• pp.550-557
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• 2012

The purpose of this study was to investigate the quality characteristics of Maejakgwa prepared with Eriobotrya japonica leaf powder (0, 1, 3, 5, 7%) substituted for flour. The pH and density of Maejakgwa dough significantly decreased in response to addition of all levels of E. japonica leaf powder. Furthermore, when spread factor values were compared among the groups, they were found to be inversely proportional to the E. japonica leaf powder concentration. With increasing amounts of E. japonica leaf powder, L and a values decreased, whereas b value increased. In terms of textural characteristics, addition of E. japonica leaf powder increased hardness, cohesiveness, springiness, chewiness, and brittleness compared to control. Finally, the results of an acceptance test showed that Maejakgwa containing 5% E. japonica leaf powder had the highest scores.

• Journal of the Korean Society of Food Culture
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• v.32 no.6
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• pp.558-565
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• 2017

This study examined the quality characteristics of cookies prepared with mulberry leaf powder (0, 1, 3, 5, and 7%) substituted for flour. The pH of the cookie dough decreased significantly in response to the addition of all levels of mulberry leaf powder. The spread factor of the cookies also increased significantly with increasing mulberry leaf powder content added to the cookies recipe. In addition, the Hunter's color L and a values decreased significantly with increasing mulberry leaf powder content, whereas the b value increased. According to hardness measurements, the substitution of 1~7% mulberry leaf powder resulted in increased hardness compared to the control. Moreover, the DPPH free radical scavenging activity of the cookies was increased significantly (p<0.05) with increasing levels of mulberry leaf powder. The sensory evaluation revealed cookies containing 3% to have the highest scores.

• Journal of the Korean Society of Food Culture
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• v.23 no.6
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• pp.771-778
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• 2008

This study was conducted to investigate the quality characteristics of cookies prepared using skate powder (0, 1, 3, 5, 7%) as a substitute for flour. The pH of the cookie dough decreased significantly in response to the addition of all levels of skate powder. However, there were no significant differences in the dough values among the test groups. Furthermore, when the spread factor values were compared among groups, they were found to be inversely proportional to the skate powder concentration. In addition, the Hunter's color L, a and b values decreased significantly as the level of skate powder increased. Moreover, the addition of 1-7% skate powder resulted in increased hardness, cohesiveness, springiness, and brittleness when compared to the control. Finally, the results of the sensory evaluation and acceptance test showed that the cookies containing 3% skate powder had the highest scores.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.2
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• pp.234-241
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• 2014

In this study, we assessed the antioxidant activities and quality characteristics of cookies containing various concentrations (0, 1, 3 and 5%) of Eleutherococcus sessiliflorus leaf powder. Antioxidant activity was estimated based on DPPH free radical scavenging activity and total content of phenolic compounds in Eleutherococcus sessiliflorus leaf powder and cookies. The quality characteristics of Eleutherococcus sessiliflorus leaf cookies were estimated based on spread factor, loss rate, leavening rate, color, texture and sensory evaluation, polyphenol contents, DPPH free radical scavenging activity, as well as spread factor of cookies significantly increased. L value, b value and hardness of cookies decreased with increasing Eleutherococcus sessiliflorus leaf powder content. Finally, the sensory evaluation showed the highest scores for cookies containing 3% Eleutherococcus sessiliflorus leaf powder. From these results, we suggest that Eleutherococcus sessiliflorus leaf is a good ingredient for increasing consumer acceptability as well as the functionality of cookies.

• Korean journal of food and cookery science
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• v.25 no.1
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• pp.98-105
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• 2009

This study examined the effects of adding four different amounts (0%: control, 4%: M-4, 8%: M-8, 12%: M-12) of button mushroom (Agaricus bisporous) powder on the quality characteristics of cookies. The bulk density and pH of the dough, and firmness, color, spread factor, consumer acceptability of cookies, and total phenol compound content and free radical scavenging activity of mushroom powder and cookies were measured. While the bulk density and pH of the dough as well as spread factor of the cookies significantly decreased, the firmness, L values and total phenol compound contents and free radical scavenging activity of the cookies significantly increased with increasing mushroom powder content(p<.05). The consumer acceptability scores for the button mushroom cookie groups ranked significantly(p<.05) higher than those of the control group in general acceptability, appearance, flavor, color, taste, and texture. This study suggests that button mushroom powder is a good ingredient for increasing the acceptability and functionality of cookies.