• Korean Journal of Materials Research
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• v.4 no.5
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• pp.600-607
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• 1994

Optimum exper~mental conditions were established for the growth of heteroepitaxial GaAs layers on InP using liquid phase epitaxy (LPE) technique. Results showed that the optimum growth temperature was $720^{\circ}C$ at a cooling rate of $0.5^{\circ}C$/min. Surface morphology of the grown layers significantly improved by addition of about 0.005wt% Se to the Ga growth melt, which effectively suppressed melt-back of InP substrates into the melt during the initial stage of growth. It was observed that the quality of GaAs layers also improved substantially when the substrates patterned with grating structure were used, as determined by the (400) double crystal X-ray diffraction. The transmission electron microscopy observation indicated t.hat the misfit dislocations interact with each other at the grating region, resulting in a lower dislocation density in the upper GaAs layer.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.47 no.3
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• pp.265-271
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• 2021

Nanoparticles are substances that are smaller in size and smaller than cells that make up the skin. Therefore, they are very suitable as mediators for transmitting drugs or genes across cell membranes, and also deliver specific ingredients into the skin.In this study, nanoparticles were extracted from mugwort and particles of around 100 nm were obtained through dynamic light scattering (DLS), and the results of concentration-dependent enhancement of cell viability in fibroblasts were obtained through MTT assay. In addition, it was confirmed that the COL1A1 mRNA expression level was increased and the IL-6 mRNA expression level was decreased through the quantitative real-time PCR analysis method. Moreover, as these nanoparticles were confirmed to be stable, they can be applied not only to cell experiments but also to cosmetic formulations. While the demand for plant-derived ingredients continues to increase, excluding chemical ingredients from the recent cosmetics industry trend, there is a limitation in that there are few research results suggesting the application field of plant-derived nanoparticles. Therefore, in order to overcome the limitations of the cosmetic industry at the present time, the results obtained in this study present nanoparticles derived from Artemisia princeps (NDAP) as a highly functional cosmetic material.

• Journal of Life Science
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• v.29 no.4
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• pp.470-477
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• 2019

White jelly fungus (Tremella fuciformis Berk) is effective for hypertension, diabetes, obesity, lung disease, beauty, and has been known as an elixir of life in ancient Chinese dynasty. In this study, we investigated the anti-obesity and diabetic effects of the fermented white jelly fungus extract by the bioconversion process. We fed an obesity-inducing mouse with 5% non-fermented Tremella fuciformis (TF), 2.5% fermented Tremella fuciformis (FTF), and 5% FTF containing High Fats Diet (HFD) and HFD for 8 weeks, respectively. The oral glucose tolerance test (OGTT) was performed analysis after 7 weeks of feeding and the dietary intake, food efficiency ratio, body weight, liver, epididymal fat weight, and serum insulin level were measured after 8 weeks of feeding. Also, HOMA-IR was analyzed. The concentrations of serum total cholesterol, triglycerides test was analyzed. The FTF compare with 5% TF and HFD confirmed that 5% FTF reduced body weight, tissue weight, triglycerides concentration, HOMA-IR, respectively. As a result, we confirmed that the fermented white jelly fungus has the anti-obesity effect. Finally, this study can be used a basic data for obesity treatment using fermented white jelly fungus.

• Korean Journal of Construction Engineering and Management
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• v.20 no.4
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• pp.104-113
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• 2019

Construction dispute about Extension of Time are complexly intertwined with various issues. The duration delay analysis defines the impact the issue has on the duration variation. And The international court and the arbitrator use the results of the analysis as a basis for reasonable duration judging. However, most of the domestic Construction sites have not established a business process for Extension of Time litigation. Therefore, Analysis data are collected after the occurrence of the dispute, there is not enough basic data of analysis almost. This study sought to improve the management efficiency by organizing information requirement for delay analysis and suggesting a reasonable business process. As a result of applying the proposed process to actual construction duration extension disputes, about 33% of practitioners, 46% of contractors, and 48% of legal advisors were satisfied with the process application site And Matrix validation was 91% identical. This study suggests that it is possible to increase the efficiency of the construction duration analysis work used as a basis in the construction dispute. Finally, the Computer based system design for this process should continue in the future.

• Microbiology and Biotechnology Letters
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• v.47 no.3
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• pp.323-331
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• 2019

White jelly fungus (Tremella fuciformis Berk; TF) has been used as a traditional medicine in Asia; it is known to prevent hypertension, aging, cancer, and arteriosclerosis. This study aimed to investigate the anti-diabetic effects of fermented Tremella fuciformis Berk (FTF) ethanol extracts fermented with L. rhamnosus BHN-LAB 76. We show that FTF increases the ${\alpha}$-glucosidase inhibitory activity and suppress the adipogenesis of 3T3-L1 adipocytes. These inhibitory effects of FTF are accompanied by the regulation of the phosphorylation of AMPK, JNK, and Akt. These data demonstrate that FTF not only inhibits adipogenesis by affecting the adipogenic signaling, but also increases the anti-diabetic effects by regulating the insulin signaling pathway. Therefore, we suggest that the FTF can be used for developing functional food and cosmetics materials.

• Journal of Korea Water Resources Association
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• v.52 no.8
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• pp.555-563
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• 2019

Reduced thickness of the water pipes due to corrosion makes it difficult to perform the original functions since corrosion in metallic water pipes can occur over time. In this study, reliability model that can estimate the probability of pipe breakage is developed regarding corrosion depth increment according to service year. Probability of pipe breakage was calculated by FORM(First Order Reliability Method) and unsteady analysis was performed to analyze the statistical properties of water pressure. And KCIP(Korea Cast Iron Pipe) equation was adopted for the reliability function. Furthermore, change of pipe thickness was estimated by Nahal and Khelif equation and Romanoff equation. Therefore, pipe thickness was calculated due to change of corrosion depth and probability of pipe breakage was calculated and compared with 10, 20, 30 service years. From the results, probability of pipe breakage for network A is gradually increased from 6.8% to 8.6% according to service year of 10, 20, 30 when Nahal and Khelif equation is applied. And probability of pipe breakage for network A is also gradually increased from 6.4% to 8.9% according to service year of 10, 20, 30 when Romanoff equation is applied.

• Journal of Life Science
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• v.29 no.8
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• pp.846-853
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• 2019

Phytochemical compounds of Ligusticum striatum Makino are used as traditional medicinal herbs in Asia. These compounds are reported to have pain relief and antioxidant activities in gynecological and brain diseases. In this study, we investigated the antioxidant effects of Ligusticum fermented ethanol extract from Lactobacillus plantarum BHN-LAB 129 isolated from Kimchi, a Korean traditional food. The total polyphenol and total flavonoid contents increased by about 116.2% and 281.0% respectively, in the fermented Ligusticum extract as compared with those in the nonfermented Ligusticum ethanol extract. Superoxide dismutase-like (SOD), DPPH radical scavenging, ABTS radical scavenging, and reducing power activities increased by around 139.9%, 199.6%, 301.0%, and 137.1%, respectively, in the fermented Ligusticum ethanol extract as compared with these parameters in the nonfermented Ligusticum ethanol extract, respectively. In conclusion, the fermented Ligusticum ethanol extract with L. plantarum BHN-LAB 129 was effective in increasing the antioxidant effects. The bioconversion process in this study points to the potential of using Ligusticum to produce phytochemical-enriched natural antioxidant agents with high added value. The findings may prove useful in the development of improved foods and cosmetic materials.

• Journal of Life Science
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• v.31 no.2
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• pp.192-198
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• 2021

Red yeast rice has been extensively used as food and traditional medicine for thousands of years in East Asian countries. It is produced by the fermentation of a particular yeast (in general, Monascus purpureus) as rice and various cereals (barley, soybean, etc.). Monascus sp. produces many secondary metabolites during its growth, including pigments, monacolins, and γ-aminobutyric acid. Some metabolites―specifically, monacolin K, γ-aminobutyric acid, dimerumic acid, and monascus pigments―have been reported to lower cholesterol and blood pressure while showing anti-obesity effects. In this study, we investigated the anti-obesity effect of ethanol extract from red yeast barley (RYB) fermented with Monascus sp. BHN-MK 2 on 3T3-L1 cells. The anti-obesity effects of RYB extract were examined: its lipid accumulation inhibitory effect was tested by Oil Red O staining, and obesity-related mRNA expression levels were tested by real-time RT-PCR in MDI stimulated 3T3-L1 cells. The intracellular lipid content of MDI-stimulated 3T3-L1 cells decreased significantly to 5.04%, 12.24%, and 23.52% in response to 200, 400, and 800 ㎍/ml RYB, respectively. Moreovers, we evaluated that RYB extract significantly downregulated the expression of C/EBPα, SREBP-1, and PPAR-γ gene in a dose-dependent manner. As a result, red yeast barley ethanol extracts exerted the strongest anti-obesity effects. Also, the results indicate that red yeast barley could be used as a functional anti-obesity food material.

• Journal of the Korea Society of Computer and Information
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• v.26 no.1
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• pp.135-146
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• 2021

VMP(Variable Message Protocol) is bit-based variable message processing protocol that enables the sharing situation information in real time as a tactical datalink protocol for Korean Army. System A is currently under development and will be operated as an army system when its development is completed. In system A, the VMP processing terminal is mounted and the VMP is utilized for exchanging tactical information. System A can acquire situation information from mounted situation information acquisition system and share situation information with other system A by the VMP. In this paper, we propose a method of sharing situation information with system A and speed improvement methods of sharing situation information using VMP. As speed improvement methods of sharing situation information, this paper studied 'Removing Process of Sending VMP Observation Report', 'Adopting One-time Situation Information Send Button When Sharing A System Situation Information By VMP', 'Combination of Many VMP Messages Using Repeat Function Of Application Header'. And we conducted the experiment, the result was that the transmission speed of equipment to which the research method was applied was improved by 76.8% compared to the existing equipment.

• Korean Medical Education Review
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• v.23 no.2
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• pp.128-138
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• 2021

This study examined the relationships among personality traits, coping efficacy, and academic stress in medical and non-medical students in South Korea, and investigated the mediating effect of coping efficacy in the relationship between personality traits and academic stress. The study group comprised 210 medical students and 175 non-medical students. They were asked to rate their personality traits, coping efficacy, and academic stress. The data were analyzed using IBM SPSS ver. 26.0 (IBM Corp., Armonk, NY, USA) and AMOS ver. 26.0 (IBM Corp.). Medical students scored higher for examination stress and lower for extroversion than non-medical students. In both groups, extroversion and conscientiousness positively affected coping efficacy, while neuroticism influenced it negatively. Neuroticism directly influenced all types of academic stress in both groups, while extroversion and conscientiousness only had direct effects on examination stress among medical students. Coping efficacy mediated the associations between personality traits and academic stress, except for the relationship between neuroticism and grade stress among medical students. The study indicates that coping efficacy had a significant effect on relieving academic stress among students with higher scores for extroversion and conscientiousness. Efforts should be made to decrease neuroticism to lower academic stress, as the relationship between neuroticism and academic stress is not directly influenced by coping efficacy. The implications of these results are discussed regarding a consultation system for students, especially those in medical school.