• Transactions of the Korean hydrogen and new energy society
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• v.34 no.3
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• pp.274-282
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• 2023

This study conducted direct numerical simulations of the natural convection phenomena of gaseous hydrogen in a physical storage container containing four circular cylinders. Rayleigh numbers (Ra) in the range of 10⁴≤Ra≤10⁶ and a Prandtl number (Pr)=0.69 (gaseous hydrogen) were considered. The main parameter is a horizontal distance of four circular cylinders and the values of ε_h=0.1, 0.2, 0.3, 0.4, and 0.5 are considered. The flow and thermal structures and corresponding heat transfer characteristics are investigated with respect to the transition of the flow regime. The time- and surface-averaged Nusselt number on the cylinder surface and the wall of physical storage container increased by about 57% and 69% according to the Ra and ε_h, respectively. Thus, the horizontal distance has an influence on the heat transfer characteristics on natural convection of gaseous hydrogen.

• Journal of Animal Reproduction and Biotechnology
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• v.38 no.3
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• pp.167-176
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• 2023

Background: A breast cancer is the second leading cause of cancer death in women worldwide and among different types of breast cancers, triple-negative breast cancer (TNBC) has a poor prognosis. Methods: We investigated the potential of ginsenoside compound K (CK), an active ingredient in the bio-transformed ginsenoside, to be used as a therapeutic ingredient by examining the effects of CK on cell proliferation, apoptosis, and cancer-related gene expressions in breast cancer cells. Results: From the results of treating MCF-7, an ER and PR-positive breast cancer cells, and MDA-MB-231 (TNBC) with CK at a concentration of 0-100 µM, the half maximal inhibitory concentration (IC₅₀) values for each cell were 52.17 µM and 29.88 µM, respectively. And also, it was confirmed that cell migration was inhibited above the IC50 concentration. In addition, fluorescence analysis of Apoptosis/Necrosis showed that CK induced apoptosis rather than necrosis of breast cancer cells. Through qPCR, it was confirmed that the expression of genes related to apoptosis and cell cycle arrest was increased in CK-treated breast cancer cells, and it acted more effectively on TNBC. However, the expression of genes related to tumor invasion and metastasis is also increased, so it is necessary to consider the timing of application of CK as a potential therapeutic anticancer compound. Conclusions: CK showed a stronger inhibitory effect in TNBC with poor prognosis but considering the high tumor invasion and metastasis-related gene expression, the timing of application of CK should be considered.

• The Journal of Industrial Distribution & Business
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• v.10 no.6
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• pp.39-50
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• 2019

Purpose - Since the local liquor industry uses the agricultural products produced in the region as the main raw material, cultivation of the industry can be a way to expand the demand for domestic agricultural products and can contribute to the income increase of the farmers. In addition, the local liquor industry can be developed into a region-specific industry differentiated from other regions by linking with the region's tourism resources. Therefore, in order to achieve various derivative effects through promotion of the local liquor industry, it is necessary to precisely understand the factors related to the purchase and consumption of local liquor which then will lead to an increase in consumption. This study analyzes the current status and problems of local liquor industries and examines the determinants of consumers' purchasing decisions of regional specialties through questionnaires. We will then propose a strategy to promote consumption of locally produced alcoholic beverages. Research design, data, and methodology - An online Domestic Consumer Survey was conducted to identify the actual purchases and uses of local liquors for 500 consumers nationwide. Based on the questionnaire results, the analysis uses an ordered probit model. Results - As a result of analyzing the effect of consumer characteristics on the purchase of local liquors, it was found that the average cost of drinking, income, local specialty, brewery experience, and health concerns have a significant effect on gender, drinking frequency. All the variables except the participation in the training of the special provincial manufacturing method were found to be statistically significant. The statistical significance was at a 1% significance level for the remaining factors excluding the bottle design. This shows that the higher taste, quality, price, and harmony with food, the higher the probability of purchasing local liquors. Conclusions - In the analysis of factors influencing the purchase intention of local liquors, it was found that factors such as taste, quality, price, and harmony with food had a significant effect. Given the diversity of purchasing factors, the importance of diversification strategies is emphasized again. In particular, it will be important to secure wide publicity for local liquors through various PR strategies.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.10
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• pp.1869-1879
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• 2000

A series of experiments were conducted for modeling the fate and effect of the coupled oxidation reduction reaction of ethanol and propionate recognized as important intermediates in anaerobic degradation metabolism. Anaerobic kinetics for conversion of propionate and the interaction with ethanol were investigated using the model of specific substrate priority utilization effect. Seed cultures for the experiment were obtained from an anaerobically enriched steady-state propionate master culture reactor (HPr-MCR), ethanol-propionate master culture reactor (EtPr-MCR) and glucose master culture reactor (Glu-MCR). Experiments were consisted of four phases. Phase I, II and III were conducted by fixing the propionate organic loading as 1.0 g COD/L with increasing ethanol loading of 0, 100, 200, 400 and 1,000 mg/L, to find metabolic interaction of ethanol and propionate degradation by each enriched anaerobic culture. In phase IV, different mixing ratios of Glu-MCR and HPr-MCR cultures with fixed propionate organic loading, 1.0 g COD/L, were applied to observe the propionate degradation metabolic behavior. In the results of this study, different pathways of propionate and ethanol conversion were found using a modified competitive inhibition kinetic model. Increase of $K_{s2}$ value reflected the formation of acetate followed by ethanol degradation. In addition. $K_3$ value was increased slightly as the reactions of acetate formation and degradation were occurred in acetoclastic methanogenesis.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.2
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• pp.129-136
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• 2016

The purpose of this study is to examine the sealing effect and efficiency of root canal filling MTA (Endoseal, Endoseal MTA). A total of 106 extracted single rooted teeth were used and classified with group AH (AH-26), group PR (ProRoot MTA), group ES (Endoseal) and group EM (Endoseal MTA) depending on filled sealers. Time was measured in each group when sealers were filled. The groups were divided into subgroup A and subgroup B. The sealing of root canal walls and penetration of sealer in the dentinal tubule were evaluated, respectively. According to the results, the sealing of root canal walls and dentinal tubule penetration of root canal filling MTA were inferior to AH-26 (p < 0.05). When compared with ProRoot MTA, however, there was no significant difference in sealing of root canal walls (p > 0.05), but dentinal tubule penetration was high (p < 0.05). Working time was shorter in root canal filling MTA than ProRoot MTA and AH-26 (p < 0.05). In conclusion, root canal filling MTA has lower root canal sealing effect than resin-based sealer, however, when in MTA needed root canal filling, it could be an effective alternative.

• The Journal of the Korea Contents Association
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• v.10 no.3
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• pp.241-249
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• 2010

The purpose of this study is to provide basic information for marketing strategy for hospitals in Busan Metropolitan area by investigating of the web-site management and effect on hospital management about the web-sites managers. Survey of 53 web-site managers was taken between May 1st and May 25th 2008. The survey was carried out to gather information about characteristics of web-site managers and creating, managing and operating process of web-sites and web-sites' effect and information sharing abilities. The results of survey are as follows. First, most of hospitals' web-sites were launched between 2001 to 2005 via outsourcing. Most of hospitals spent about one to three million won for their web-sites and renew web-sites every year. Most of these web-sites have hospital PR, Q&A, and on-line support functions. Second, most of whom participated in survey have agreed that a hospital web-site has influence in hospital management in various categories such as introducing hospital to medical examination, making doctor's appointment, providing patient guidance, providing medical information, and patient counselling. This study shows that effects of web-sites are closely related to web-site satisfaction level. Therefore, to raise the hospital satisfaction level, it is necessary for hospitals to put more efforts in creating web-site that provides more medical information and improved on-line services.

• The Journal of the Korea Contents Association
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• v.16 no.3
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• pp.33-42
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• 2016

Utilization of cultural contents is more and more increasing as it is believed to improve local problems and provide historical values. This kind of business is positive in terms of the fact that it attracts visitors into local areas and activate local commercial areas. Under this trend, the construction of specialized streets is required to be approached with first priority to solve problems of cities. So to speak, it's more important to solve intrinsic problems found in local communities and then approach cultural contents step-by-step rather than constructing new spaces with first priority. Moreover, cultural contents should accompany economic aspects which result in local community-friendly and sympathetically concentrated values. Under this sentiment, the efforts to suggest economic ripple effects for government local government's businesses using cultural contents are very important. This study analyzed how much economic ripple effects is yielded by reflecting cultural contents. As the result of analysis, specialized street with cultural contents applied are proved to be more concentrated on multiplier of expediting employment, income and tax and tourism industry than service industry. On the contrary to this, service industry showed more concentrated multiplier of expediting production, income, added values and chain reaction effect (coefficients for influence and sensitivity for front and rear side of tourism industry. Based on these results, construction of specialized streets with cultural contents applied is proved to help synergy effects for local economy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.1126-1133
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• 2002

Conjugated linoleic acid (CLA) is a collective term for a class of positional and geometric conjugated dienoic isomers of linoleic acid (LA) and has anti-cancer activity in experimental animals. We have previously observed that an isomeric mixture of CLA and trans-10,cis-12 (t10c12) inhibited cell growth in a dose-dependent manner whereas LA and cis-9,trans-11 (c9t11) had no effect. The present study examined whether the CLA mixture and t10c12 induce apoptotic cell death. TSU-Prl cells were incubated for three days in serum-free medium in the absence or presence of individual fatty acids, and the DNA fragmentation assay was performed. Cells treated with the CLA mixture or t10c12 produced a distinct oligonucleosomal ladder with different sizes of DNA fragments, a typical characteristic of cells undergoing apoptosis. By contrast, LA and c9t11 had no effect. Western immunoblot analysis of total lysates revealed that t10c12 reduced anti-apoptotic, 26 kDa, Bcl-2 protein levels by 49$\pm$8% compared with controls, whereas this CLA isomer did not alter pro-apoptotic,21 kDa, Bax protein levels. These results suggest that growth inhibitory effect of the t10c12 CLA isomer may, at least in part, be attributed to Increased apoptotic death in TSU-Prl cells.

• Restorative Dentistry and Endodontics
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• v.26 no.2
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• pp.141-152
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• 2001

Eliminating the infecting bacteria of the root canal system and preventing reinfection must be the main objectives of all endodontic works. None of commercially available root canal sealers have the properties of desirable tissue compatibility and strong antibacterial activity. The purpose of this study is to develope an ideal root canal sealer using commercially available polyphosphate (polyP), Calgon, which is known to be antibacterial and safe. For the study. resin type AH26, zinc oxide eugenol type Tubli Seal. Ca(OH)$_2$ type Apexit as base sealers for polyP (0~3%) and para formaldehyde containing N2 as a control base were selected. Specimens (3$\times$4mm) of the sealers were prepared in a 37$^{\circ}C$ incubator for 3 and 10 days and their antibacterial activity against streptococci and black pigmented anaerobic rods was observed using an agar diffusion method. The result were as follows: 1. Among 3 day old root canal sealers. N2 as a positive control showed the strongest antibacterial effect. followed by AH26. Tubli Seal and. Apexit which barely showed antibacterial activity against the test bacteria. In contrast. 10 day old AH26 showed a greater antibacterial activity than 10 day old N2. 2. All sealer specimens showed a greater antibacterial activity against black pigmented anaerobic rods than streptococci. Three day old ones appeared to be more antibacterial than 10 day old ones except for Apexit. 3. As compared to N2, 3 day old AH26 demonstrated a similar antibacterial activity against black pig mented anaerobic rods but to a lesser extent to streptococci. Ten day old AH26 showed a greater antibacterial activity against black pigmented anaerobic rods than 10 day old N2. 4. As compared to AH26. Tubli Seal generally revealed a lower antibacterial activity but it showed a greater antibacterial activity aginst S. gordonii Challis. 5. Enhancement of antibacterial activity by polyP was more clearly observed when it was added to Ca(OH)$^{\circ}C$ based root canal sealers. Tubli Seal and N2. 6. The addition of polyP enhanced the antibacterial activity of 3 day old AH26 against S. gordonii G9B (16%) and Challis (29%), and P. gingivalis 2561 (24%) only. Moreover, polyP failed to increase antibacterial activity of 10 day old AH26 against the test strains but P. gingivalis A7A1 28(13%). 7. The addition of polyP increased the antibacterial effect of 3 day old Tubli Seal on several test bacteria including s. mutans GS 5 (50%). s. gordonii G9B (47%) and Challis (122%). and all the test strains of P. gingivalis (13~35%) except for 9 14K 1. The addition of polyP to 10 day old Tubli Seal increased antibacterial activity of the root canal sealer against most test strains. 8. 3 day old Apexit failed to show antibacterial activity. if any very little against S. mutans GS 5 and Pr. intermedia ATCC 49046. However. polyP increased its antibacterial activity by 50 and 69%, respectively. Increase of antibacterial activity of 10 day old Apexit by polyP was more clearly observed than that of 3 day old one.

• Journal of Distribution Science
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• v.14 no.4
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• pp.117-125
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• 2016

Purpose - As consumers' needs for purchasing fresh and safe food have been bigger in Korea, their interest in local food is also growing recently. So, the number of local food stores has been increased from 3 in 2012 to 103 in 2015. Local food stores should operate a business responding consumers' needs in order that local food stores are not to be a one-time fad. Therefore, the purpose of this study is to analyze the characteristics of consumers who use a local food store and provide helpful implications to design a strategy for sustainable growth of local food store. Research design, data, and methodology - In this study, Probit model was used for empirical analysis in order to examine the effect of purchase choice attributes of agricultural products, consumer's satisfaction, and their demographic factors upon the intention to use a local food store. After estimating coefficients of the probit model, marginal effects were calculated as a standard normal, and cumulative distribution is differentiated with respect to explanatory variables. To collect the data, questionnaire survey was carried out with the consumers using the local food store (Youngjin Nonghyup near to Jeonju city located in Jeollabuk-do). Result - The data analysis found that the more consumers are satisfied with local food store, the higher intention they have to use the local food store. In addition, it was known that the factors related to quality of agricultural products and shopping convenience among the purchase choice attributes have a considerable impact on the purchase intention of a local food store. In demographic factors, income was turned out to be an important factor affecting purchase intention of local food. Such a result supports the hypothesis that high income consumers are likely to purchase local food, which is based on the inference that consumers who have a high income tend to pursue wellbeing life. Futhermore, information delivery, through a reputable media source among general factors, was known to play an important role in forming an intention to purchase local food. According to the analysis of marginal effects, probability of purchase intention of a local food store is increased by 11.4%, if a monthly average income of a household is above 4.5 million Won(Korean currency). If purchasing satisfaction with local food stores is high, the probability of purchase intention would be increased by 24.1%. Likewise, such a probability goes up by 8.7%, 5.8%, respectively as an increasing one unit of quality of agricultural products and shopping convenience of local food stores, respectively. Conclusion - For attaining sustainable growth in a local food store, it is considered necessarily to establish a proper store operation system to meet consumers' needs, especially for quality and shopping convenience of local food. Moreover, as it was found that appropriate communication through media source has a positive effect on the intention to use local food store, PR activity seems to be necessary to expand the consumers' demands for local foods.