• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.4
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• pp.839-847
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• 2015

To seamlessly provide content through the Internet, it is generally considered to use distributed processing for content requests converged on original content providers like P2P, CDN, and ICN. That is, after other nodes temporally save content, they handle content requests instead of original content providers. However, in this case, it may be possible that a content sender is different from the original provider of the content. In this case, users may be exposed to various risks. To solve such a problem, it is highly recommended to verify received contents before using them, but it can cause network traffic increases as well as a serious service delay. This paper proposes an efficient content verification scheme for distributed networking/data store environments and analyzes its performance.

• Women's Health Nursing
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• v.29 no.3
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• pp.208-218
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• 2023

Purpose: The aim of this study was to explore the continuous usage intention of head-mounted display-based virtual reality (HMD-based VR) content among college students. The study also sought to understand how this intention is influenced by factors related to personal cognition, social aspects, VR content, and HMD-related elements. Methods: This descriptive correlational study used a self-report questionnaire to survey 217 students from two universities in Korea who had prior experience with HMD-based VR content. Results: The mean score for continuous usage intention of HMD-based VR content was 2.59±0.57 points (range, 1-5 points). Regarding the average frequency of HMD-based VR content usage, 64.5% of participants reported using it 1 to 2 times, while 91.7% indicated a total HMD-based VR usage period of less than 6 months. Factors such as personal cognition, VR content, social aspects, and HMD-related elements had explanatory power of 35.1%, 10.7%, 4.4%, and 2.5%, respectively, for the continuous usage intention of HMD-based VR content. Additionally, engagement (β=.45, p<.001), influential others (β=.37, p<.001), environmental support (β=-.18, p=.030), and cyber sickness (β=-.21, p=.001) were identified as having a significant influence. Conclusion: When developing HMD-based VR content, strategies to improve users' personal cognition should be included. Additionally, it is necessary to develop strategies that enhance enjoyment and interest in the content, while also facilitating ongoing social support. Furthermore, coping strategies should be devised that take into account cyber sickness, a potential side effect of these devices.

• The Korean Journal of Ecology
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• v.10 no.3
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• pp.119-127
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• 1987

On the east slope of the front ranges of the Colorado Rockies, USA, three species of Populus are distributed at different elevations from the Great Plains to the timberline. At elevations 1, 720m (P. sargentii), 2, 335m (P.angustifolia) and 3, 190m (P.tremuloides) chlorophyll cotents of leaves of thses dioecious trees were determined. Total chlorophyll content was in the range of 0.86-1.56mg/g leaf, increasing with elevation as a second-degree polynomial, and the peak content was estimated to be reached at about 2, 800m. Total chlorophyll content was greater in female than in male trees in the two higher elevation species, but not in P. sargentii, the low elevation species. Chlorophyll b content was greater than chlorophyll a content in the same two higher elevation species. The increase of chlorophyll b than to increase of chlorophyll a content. These phenomena appear to be the result of adaptation of these species to different environmental conditional at different elevation. Sequential distribution of plant populations on environmental gradients in such a way that variation in given plant characters paralell the environmental gradient must occur not only in ecotypes of a species, but also in different but closely related species.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.5 s.108
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• pp.69-77
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• 2004

Degradations of pine, yellow poplar and sweet gum by two fungi, Pycnoporus cinnabarinus and Trichophyton rubrum LSK-27 were investigated. P. cinabarinus degraded pine block samples much faster than T rub rum LSK-27, whereas P. cinnabarinus and T rubrum LSK-27 degraded yellow poplar and sweet gum at almost the same rate. In an effort to get a better understanding of how fungi degrade lignin in wood, contents of various functional groups were analyzed. After three-months of degradation of pine flour by these fungi, the following changes were observed: an increase in condensed phenolic OH group and carboxylic acid group content, a decrease in the guaiacyl phenolic OH content, and little change of aliphatic OH group content. Further studies in the degradation of pine flour by P. cinnabarinus indicated that the increase in condensed phenolic OH group content and the decrease in guaiacyl phenolic OH group content occurred in the first month of the degradation. The changes of functional group contents in the degradation of unbleached softwood kraft pulp by P. cinnabarinus had the same trends as those in the degradation of pine flour. That is, structural alteration of lignin due to the kraft pulping process had little effect on how P. cinnabarinus degraded lignin.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.3
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• pp.138-144
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• 1992

This study was carried out to determine the effects of lime(0, 300 kg/lOa) and phosphate application( 0, 20, 40, 80 kg/lOa) on mineral contents in herbage when 5 pasture species(orchardgrass, tall fescue, perennial ryegrass, redtop and ladino clover) were grown in pot of black(B) and very dark brown (VDB) volcanic ash soil of Cheju island, respectively. P content of orchardgrass and perennial ryegrass were higher in VDB than in B (P<0.01), but other grasses were not different between two soil types. Also, Ca and Mg contents of ladino clover were higher in VDB than in B, but other grasses were not different between two soil types. P and K contents were not affected by lime but Ca and Mg contents were increased by lime application in most of the pasture species. P, Ca, Mg and Na contents of all pasture spesies were increased by phosphate application(P< 0.Ol)except for Ca content of tall fescue. K and Fe content were decreased, with increasing phosphate application but Zn content was not changed by phosphate application.

• Food Science of Animal Resources
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• v.38 no.6
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• pp.1305-1314
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• 2018

To investigate relationships of electronic taste-traits with muscle fiber type composition (FTC) and contents of nucleotides, porcine longissimus lumborum (LL), psoas major (PM), and infra spinam (IS) muscles were obtained from eight castrated LYD pigs. FTC and taste-traits in these three porcine muscles were measured by histochemical analysis and electronic tongue system, respectively. IS had significantly higher proportion of type I fibers while LL had significantly higher proportion of type IIB than other muscles (p<0.05). IS had the highest inosine monophosphate (IMP) content while LL had the lowest IMP content (p<0.05). In contrast, LL had significantly higher hypoxanthine content compared to PM and IS (both p<0.05). For taste-traits, IS had significantly higher umami and richness values but lower sourness value than LL and PM (p<0.05). Sourness and astringency values of LL were significantly higher than those of IS (p<0.05). The proportion of type IIB fiber was positively correlated with sourness and astringency but negatively correlated with saltiness. These results suggest that sourness and astringency tastes are increased with increasing proportions of type IIB fibers in porcine muscles due to increase of hypoxanthine content. These results also imply that umami and richness tastes are increased with increasing contents of type I and IIA fibers because of increased IMP content in porcine muscles.

• Journal of Applied Biological Chemistry
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• v.63 no.3
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• pp.175-180
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• 2020

The purpose of this study was to investigate the cultivation site of Cornus officinalis (C. officinalis) by analyzing the contents of loganin and morroniside according to the cultivation environment of C. officinalis. The loganin and morroniside contents were analyzed by ultra performance liquid chromatography. Mg content and pH in soil data were found to have the greatest effect on logainin content. In soil data, Mg, Na content, pH, salinity, silt ratio and clay ratio were found to have the greatest effect on morroniside content. Therefore, Mg content, pH, and clay ratio were found to have a high effect on the contents of loganin and morroniside, which are indicators of C. officinalis. In conclusion, Mg content, pH, and clay ratio in soil may have a high effect on the contents of loganin and morroniside, which are indicators of C. officinalis.

• Food Science of Animal Resources
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• v.41 no.2
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• pp.247-260
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• 2021

This study aimed to determine the physicochemical properties (proximate composition, color, pH, salinity, water holding capacity (WHC), curing yield, and shear force) and sensory properties (electric nose and sensory evaluation) of Bulgogi sauce with added crust derived from dry-aged beef loin. Increasing the amount of crust in the Bulgogi sauce tended to increase the protein content, fat content, and pH. Uncooked Bulgogi also tended to have elevated fat content, ash content, pH, and shear force. Increasing the crust content tended to decrease the water content, lightness, redness, and yellowness of Bulgogi sauce. The yellowness of uncooked Bulgogi with 6%-12% crust in sauce was significantly lower than that of the control (no crust) and the sample with 3% crust in sauce (p<0.05). The redness of the cooked control Bulgogi was significantly lower than that of the samples with crust in sauce (p<0.05). The WHC of uncooked Bulgogi with 6%-12% crust in sauce was significantly higher than that of the control and the sample with 3% crust in sauce (p<0.05). The flavor, texture, and overall acceptability of the Bulgogi with 9% crust in sauce were significantly higher than those of the control (p<0.05). These findings showed that the crust did not degrade the physicochemical properties of Bulgogi sauce and meat. The sensory characteristics of Bulgogi marinated with 9% crust in sauce were rated the best as persensory evaluation. Therefore, crust is a suitable flavor enhancer for Bulgogi sauce, and a 9% addition amount is optimal in terms of quality.

• Korean journal of food and cookery science
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• v.14 no.3
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• pp.219-224
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• 1998

Kochujang was prepared by using retrograded rice cakes (Song Pyun, Sym rice cake, Ssuk rice cake, Pat rice cake) as a source starch and the physiochemical and sensory characteristics were compared with traditional kochujang during aging for 60 days. Moisture content of all kochujang groups increased slowly but crude fat content decreased according to aging process. Changes of pH values of all kochujang reduced gradually during aging and the pH of saccharified kochujang was lowered than that of traditional one. Total reducing sugar contents in saccharified kochujang reached the maximum value at 50th day, and decreased thereafter. In contrast, the reducing sugar content in traditional kochujang was the highest at 30-day-aging. After 60 days of aging, the total contents of organic acids were 28.57 mg for P$\_$1/, 27.9 mg for P$\_$4/, 27.05 mg for P$\_$3/ 24.60 mg for P$\_$2/, and 22.30 mg for P$\_$0/. By sensory evaluation, saccharified kochujang prepared with Siru rice cake showed the highest sensory score in its appearance, flavor, texture, color, and taste.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.517-520
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• 1993

As the pH of ground pork increased from 5.0 to 7.0, the corresponding development of 2-thiobarbituric acid reactive substance (TBARS) during storage at $4^{\circ}C$ decreased significantly (p<.001). At the 4th day of refrigerated storage, with the increase in pH of ground pork from 5.0 to 7.0, the release of free iron decreased significantly (p<.05) from 1.50 to .99 ppm. The decrease in free iron content of pH 7 pork well explains the decrease in TBARS absorbances. The fact that the addition of 2% ethylenediamine tetraacetic acid (EDTA) to pH 5 ground pork decreased the oxidative rancidity development (p<.001) strongly supported the above finding that the increased free iron content of pH 5ground pork catalyze the oxidation during storage. The activity of glutathione peroxidase (GPx) at the 4th day of refrigerated storage decreased significantly (p<.05) when the pH of ground pork decreased from 7.0 to 5.0. Both the lower free iron content and the higher activity of GPx were proved to be important factors in controlling the oxidative rancidity of high pH ground pork.