• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.2
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• pp.224-229
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• 1996

Performance characteristics of single cell in phosphoric acid fuel cell were studied for various electrode fabrication parameters such as teflon content, electrode structure, thickness of electrocatalyst layer, platinum content and electrode area. The performance of single cell was decided from the measured voltage-current through a load change. The electrode of 40wt.% teflon exhibited high initial performance of single cell, but in the long term operation, the cell performance of 45 wt.% teflon was better. Also the single cell appeared good performance in case of electrodes with duplicate structure, thin electrocatalyst in thickness, more platinum content, and small area. These results of cell performance were discussed as related to the electrolyte flooding, formation of 3 phase boundary area, internal resistance of electrode, and microstructure of electrode.

• Journal of Environmental Science International
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• v.32 no.12
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• pp.987-990
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• 2023

This study exploded the correlation between feed and livestock manure characteristics across different livestock species. The selected farms included laying hen, fattening pig, and Hanwoo farms, with visits conducted to each farm at 1-day intervals. In the experiment, feed was provided to each livestock species every day at the same scheduled time, and samples of both feed and livestock manure were collected from each farm after 1 month. The correlation analysis revealed no significant effect on the crude protein content of the feed for each livestock species and the respective livestock manure characteristics. This could be attributed to the fact that the difference in nitrogen content of each feed did not have a substantial effect on the content of the livestock manure components or the differences in individual components were similar. Based on these results, it is crucial to conduct environmental impact assessments on farms using diverse feeding management approaches for each farm.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.471-478
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• 2023

This study investigated the quality characteristics and antioxidant activities of salad dressing prepared with Jerusalem artichoke powder (0%, 4%, 8%, and 12%). The pH, soluble solid content, and viscosity increased as the content of Jerusalem artichoke powder increased. The titratable acidity showed no significant differences between samples. The lightness values decreased, while the redness and yellowness values increased with increasing amounts of Jerusalem artichoke powder. The total polyphenol content ranged from 52.00-69.64 ㎍ GAE/g, and increased with the increase in Jerusalem artichoke powder levels. The antioxidant activities measured via DPPH and ABTS radical scavenging activity and reducing power also increased with increasing Jerusalem artichoke powder, at a higher rate than in the control. These results suggest that it is beneficial to add Jerusalem artichoke powder when in salad dressing.

• The Korean Journal of Food And Nutrition
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• v.37 no.3
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• pp.152-161
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• 2024

This study investigated the influence of incorporating chestnut inner shell powder (CISP) at varying levels (0%, 3%, 6%, 9%, and 12% w/w) on the quality, antioxidant potential, and consumer preference of garaetteok, a Korean rice cake. Findings revealed a decrease in moisture content and pH with increasing CISP content. Color analysis indicated a reduction in lightness (L) and yellowness (b) values, while redness (a) values increased. Textural properties displayed an increase in hardness, chewiness, and gumminess, but a decrease in springiness, adhesiveness, and cohesiveness with increasing CISP levels. Sensory evaluation for appearance, taste, flavor, texture, and overall preference revealed the sample containing 6% CISP to be the most favorable. Moreover, the antioxidant activity of the garaetteok exhibited a positive correlation with increasing CISP content. In conclusion, incorporating 6% CISP resulted in improved quality characteristics for garaetteok development, offering enhanced nutritional value, antioxidant properties, and overall consumer preference.

• Journal of the Korean Geosynthetics Society
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• v.22 no.3
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• pp.37-46
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• 2023

In this paper, the physical properties, stress deformation and strength characteristics, density and permeability characteristics of silty sand (SM) by fines content were analyzed through indoor tests. also based on the results of the indoor tests, a compact analysis was performed according to the content of SM, and the applicability of SM ground to the compacted target layer was evaluated by comparing it with the measurement data of the actual problem site. As a result of indoor tests and compression analysis, SM changed its mechanical properties from sandy soil to viscous soil when the fine particle content was 35% or higher, and using field measurement data, SM was found to have a higher compression tendency than direct subsidence. Therefore, the mechanical characteristics of SM above Fc 35% are considered to be similar to that of viscous soil, which is different from the compression characteristics of the tendency of immediate subsidence to conventional sandy soil, so it is necessary to present the mechanical characteristics of SM through further research. The research findings highlight the importance of considering consolidation settlement in silty sand (SM) when evaluating soft soil conditions. These findings can aid in revising criteria for assessing weak ground conditions by providing essential engineering property data based on varying fines content in silty sand.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.1
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• pp.126-135
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• 2014

This study was conducted to evaluate the quality characteristics of sponge cake consisting of 10%, 20%, 30%, 40% and 50% Helianthus tuberosus powder (HTP). With higher HTP contents in sponge cake, pH of sponge cake batter decreased significantly, whereas specific gravity was increased significantly (p<0.05). Meanwhile volume and symmetry indices of sponge cake were inversely proportional to HTP amounts. With higher HTP content in sponge cake, L value (brightness) of crumb significantly decreased (p<0.05), whereas a value (redness) significantly increased (p<0.05). b value (yellowness) of crumb in 40% and 50% HTP sponge cakes were significantly different from b value of crumb in 10%, 20% and 30% HTP sponge cakes. In 10~40% HTP sponge cake, L value, a value and b value all decreased significantly with higher HTP content in sponge cake. However in 40% and 50% HTP sponge cakes, there was no significant difference in any value. For texture characteristics, hardness of sponge cake significantly increased while cohesiveness decreased (p<0.05) with higher HTP content in sponge cake. On the other hand, springiness and gumminess of sponge cake did not change. Sponge cake containing 10% HTP showed the highest values for every organoleptic property. The results of this study suggest that sponge cake containing 10% HTP is the most appropriate for quality characteristics. This study also provides a way to increase the quality, texture characteristics, and organoleptic properties of sponge cake while reducing HTP content to less than 10% in order to qualify consumer taste.

• Korean journal of food and cookery science
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• v.24 no.1
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• pp.31-38
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• 2008

Sulgidduk samples made with additions of 1, 2, 3, 4, and 5% Ulmus cortex powder, and a control, were examined for quality characteristics such as moisture content, color, gelatinization properties, textural characteristics, and consumer acceptance, in order to determine the optimal ratio of Ulmus cortex powder in the formulation. The moisture contents among the samples were not significantly different, ranging from 40.57 to 42.37%, and increased as the Ulmus cortex powder content increased. For the color values, lightness decreased and yellowness and redness increased with increasing Ulmus cortex powder content. With regard to the gelatinization properties, peak viscosity (P), trough viscosity (T), final viscosity (F), breakdown, and consistency increased with increasing amounts of Ulmus cortex powder. Pasting temperature, time to peak viscosity, and setback presented decreasing tendencies with the additions of Ulmus cortex powder. For the textural characteristics, increasing Ulmus cortex powder content presented decreases in hardness, springiness, and chewiness however, adhesiveness, cohesiveness, and gumminess were not significantly different among samples. In the consumer acceptance test, the scores of all evaluated characteristics decreased as the ratio of Ulmus cortex powder increased. However, the intensity ratings for the 1 and 2% Ulmus cortex powder samples showed the opposite effect, obtaining fairly good scores. In conclusion, the results indicate that adding $1{\sim}2%$ Ulmus cortex powder to Sulgidduk is optimal, providing good physiological properties and reasonably high consumer acceptability.

• Journal of the Korean Society of Food Culture
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• v.29 no.2
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• pp.195-204
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• 2014

This study was conducted to evaluate the quality characteristics and antioxidant activities of rice flour sponge cakes containing 0, 20, 30, 40, and 50% Helianthus tuberosus powder (HTP). As HTP content of sponge cake increased, the pH of sponge cake batter significantly decreased, whereas specific gravity significantly increased (p<0.05). Meanwhile, volume and symmetry indices of sponge cake were inversely proportional to HTP amount. Further, with higher HTP content in sponge cake, L and b values of crumbs significantly decreased (p<0.05), whereas a value significantly increased (p<0.05). L, a, and b values of crust significantly increased with higher HTP content. For texture characteristics, hardness, cohesiveness, gumminess, and chewiness of sponge cake significantly increased (p<0.05),whereas cohesiveness did not significantly change. In the sensory evaluation test, rice sponge cake prepared with 10% HTP showed the highest sensory scores in terms of color, flavor, taste, softness properties, and overall preference. The levels of total polyphenol compounds and DPPH radical scavenging activities of rice sponge cakes significantly increased with higher HTP contents (p<0.05). The results of this study suggest that rice sponge cake containing 10% HTP is the most appropriate for quality characteristics and sensory evaluation. This study also provides a way to increase the quality, texture characteristics, and organoleptic properties of sponge cake while reducing HTP content to less than 10% in order to satisfy consumer tastes.

• Korean Journal of Food Science and Technology
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• v.54 no.2
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• pp.141-146
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• 2022

This study investigated the quality characteristics and antioxidant activities of preserved jams prepared by mixing various ratios of aronia and sugar. To analyze the quality characteristics, the total sugar, pH, moisture, maximum stress, hardness, total phenolics, 1,1-diphenyl-2-picrylhydrazyl (DPPH), trolox-equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and sensory characteristics of the preserved jams were measured. Lower aronia contents resulted in higher total sugar content, hardness, and strength, as well as lower moisture, total phenolic content, and DPPH, TEAC, FRAP, and ORAC values. In terms of the sensory characteristics, an aronia content of 30%, which was determined to have strong sweetness and texture, resulted in the lowest overall acceptability. In contrast, the highest preference was shown to an aronia content of 40%. In this study, quality characteristics and antioxidant activity experiments were conducted based on various ratios of aronia and sugar. The results are expected to be used as preliminary data for developing products that use domestic aronia.

• Korean Journal of Poultry Science
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• v.22 no.4
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• pp.223-223
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• 1995

A study was conducted to compare the quality characteristics among commercial broiler, Wangchoo (imported dual purpose breed) and Korean native chicken(KNC). Thigh and breast meat of the broiler(7-wk old), Wangchoo(15-wk old), and Korean native chicken(15-wk old) stored for 24 h at 5t were used to analyze chemical composition, physico-chemical characteristics, textural traits and sensory evaluation test. Crude fat and moisture contents in broiler meat and crude protein content in KNC were significantly(P<.05) higher than those in the other breeds regardless of parts of the body. Total collagen content in broiler meat was significantly higher than those of the other breeds, however, the heat-soluble and the acid-soluble collagen content in Wangchoo were significantly lower than those of the other breeds. Water-holding capacities of KNC in breast meat, and of broiler in leg meat were significantly higher than that of the other breeds, while the results of the water-holding capacity and the cooking loss were reversed. Myofibrillar fragmentation index in broiler meat was significantly higher than that in the other breeds regardless of body parts. Hardness, elasticity and cohesiveness in Wangchoo were significantly higher than those in the other breeds. The prominent fatty acids were oleic, palmitic and linoleic acids and run up to 79.03~83.82 %, regardless of breeds and parts. The sensory evaluation score of tenderness, taste and preference in Wangchoo were lower compared to the broiler and KNC, however, they were not significantly different between broiler and KNC. In conclusion, the quality characteristics of KNC were excellent compared to Wangchoo.