• Applied Chemistry for Engineering
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• v.29 no.4
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• pp.440-445
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• 2018

In this study, the stability of O/W cosmetic facial cream emulsions according to HLB values was evaluated by mixing nonionic surfactants, such as Brij 78&72 and Brij 98&92. Brij 78&72 (steareth-20&steareth-2, EMS-01), saturated fatty acid, and Brij 98&92 (oleth-20&oleth-2, EMS-02), unsaturated fatty acid, were used as mixed surfactants. The stability of the O/W emulsion was evaluated by using the emulsion viscosity, particle size, particle size distribution, and zeta-potential. The viscosity of the emulsion increased with the increase of time for EMS-01 while that of EMS-02 decreased with the increase of HLB value. The particle size of both EMS-01 and EMS-02 increased with time. The emulsifier with a HLB value of 10.8, which is the most similar to the required HLB value of mineral oil, 10.5, had the smallest particle size and highest density and also showed the highest emulsion stability. The zeta-potential of both emulsions tended to increase with the HLB value. No significant changes were observed in emulsions of the HLB value of 10.8 or more. The saturated fatty acid system, EMS-01, exhibited a higher zeta-potential value than that of the unsaturated fatty acid EMS-02 and also was superior in the stability.

• Journal of Preventive Medicine and Public Health
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• v.55 no.4
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• pp.389-397
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• 2022

Objectives: This study examined the effect of out-of-pocket (OOP) payment reduction on the potential utilization of low-value magnetic resonance imaging (MRI) across income groups. Methods: We conducted an experimental vignette survey using a proportional quota-based sample of individuals in Korea (n=1229). In two hypothetical vignettes, participants were asked whether they would be willing to use MRI if they had uncomplicated headache and non-specific low back pain, each before and after OOP payment reduction. To account for the possible role of physician inducement, half of the participants were initially presented with vignettes that included a physician recommendation for low-value care. The predicted probability, slope index of inequality (SII), and relative index of inequality (RII) were calculated using logistic regression. Results: Before OOP payment reduction, the lowest income quintile was least likely to use low-value MRI regardless of physician inducement (36.7-49.6% for low back pain; 30.5-39.3% for headache). After OOP payment reduction, almost all individuals in each income quintile were willing to use low-value MRI (89.8-98.0% for low back pain; 78.1-90.3% for headache). Absolute and relative inequalities concerning potential low-value MRI utilization decreased after OOP payments were reduced, even without physician inducement (SII: from 8.15 to 5.37%, RII: from 1.20 to 1.06 for low back pain; SII: from 6.99 to 0.83%, RII: from 1.20 to 1.01 for headache). Conclusions: OOP payment reduction for MRI has the potential to increase low-value care utilization among all income groups while decreasing inequality in low-value care utilization.

• Asia pacific journal of information systems
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• v.19 no.1
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• pp.83-111
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• 2009

Despite the growing emphasis on the importance of knowledge exchange among supply chain participants, few companies have fully exploited the knowledge resources held by their supply chain partners. Among many reasons for this phenomenon, recent literature on inter-firm knowledge exchange identifies knowledge complementarities between the supply channel partners as an important determinant of knowledge exchange. Firms participating in a supply chain are likely to exchange partners' complementary knowledge. In order to extract value from them, it is important to recognize the difference between the potential value and the implementation of this potential value. However, the literature fails to distinguish between potential knowledge complementarities and implemented knowledge complementarities. In order to realize the value of potential knowledge complementarities, knowledge should be exchanged and effectively integrated in the supply channel. Further, investigating inter-firm knowledge exchange from both partners' perspectives is important especially when there are interdependencies between the channel partners. The purpose of this research is to investigate the impact of potential knowledge complementarities on knowledge exchange in buyer-supplier relationships by looking at both partners' perspectives. This research also includes trust in partner's competence and inter-organizational information systems (IOIS) as they are relevant when the complementary knowledge flows between organizations. The data required for this field study was collected from 70 buyers and their suppliers in three multinational enterprises in two different industries (Automobile manufacturing and Telecommunication services) headquartered in Korea. The results indicate that potential knowledge complementarities between buyer and supplier do not directly influence knowledge exchange, but indirectly through trust in partner's competence. And the results indicate that competence-based trust and IOIS have direct effects on knowledge exchange. Empirical results also show that IOIS moderates the relationship between potential knowledge complementarities and knowledge exchange. This study is a first attempt to empirically verify the theoretical model about potential knowledge complementarities and to investigate the impact of potential knowledge complementarities on interfirm knowledge exchange. From a theoretical perspective, this study not only clarifies the distinction between potential knowledge complementarities and implemented knowledge complementarities, but also develops an instrument to measure the concept of potential knowledge complementarities in the context of operational and planning knowledge in a supply chain. Further, we develop a theoretical framework suggesting that potential knowledge complementarities of partners in a supply chain affect knowledge exchange directly and indirectly through competence-based trust. The findings from this study have some managerial implications for practicing managers as well. First, buyers should search for suppliers that have potential complementary knowledge, which can be integrated to create synergy through interfirm knowledge exchange. Furthermore, firms must develop mechanisms to identify potential complementary knowledge of partners. Second, firms should continue their endeavor to develop their own unique knowledge so that their knowledge can benefit the entire supply channel. Finally, trust among supply chain partners turns out to be an important factor for interfirm knowledge exchange. Therefore, effective management for engendering trustworthy buyer-supplier relationships should receive appropriate attention from managers.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.4
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• pp.21-30
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• 2022

To mitigate the environmental impacts of the energy sector, the government of South Korea has made a continuous effort to facilitate the development and commercialization of renewable energy. As a result, the efficiency of renewable energy plants is not a consideration in the potential site selection process. To contribute to the overall sustainability of this increasingly important sector, this study utilizes the Black-Scholes model to evaluate the economic value of potential sites for off-site wind farms, while analyzing the environmental mitigation of these potential sites in terms of carbon emission reduction. In order to incorporate the importance of flexibility and uncertainty factors in the evaluation process, this study has developed a site evaluation model focused on system dynamics and real option approaches that compares the expected revenue and expected cost during the life cycle of off-site wind farm sites. Using sensitivity analysis, this study further investigates two uncertainty factors (namely, investment cost and wind energy production) on the economic value and carbon emission reduction of potential wind farm locations.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.1
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• pp.51-59
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• 1998

This paper presents a new present value measure, the dynamic present value, or DPV. DPV takes into account not only the value of the realized cash flow but also that of potential cash flow. The DPV approach enables the analyst to observe differences in the present value of the alternatives every period over the whole time period of interest. This is the most fundamental advantage of the DPV approach over the traditional present value approach in which the present value of the alternatives is evaluated only one particular point of time. The concepts of the realized and potential cash flows are also developed in this paper. These new concepts are found to be useful elements in evaluating economic alternatives.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.927-930
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• 2006

This study was conducted to investigate potential effects of previously identified QTL regions on carcass traits in Hanwoo. The data analyzed in this study was collected from 326 steers of 67 proven sire. Thirteen micorsatellite markers spanning QTL regions on bovine chromosomes 1 and 14 were genotyped in 326 steers. The following breeding values were analyzed for QTL effects. Cold carcass weight breeding value (CCWBV), longissimus muscle area breeding value (LMABV), marbling score breeding value (MSBV) and backfat thickness breeding value (BFTBV). Chi-square tests were performed to compare frequencies of individual allele between high and low breeding value groups. Significant differences of allele frequencies in BMS711, MCM130, BMS4049, and BMS2263 were found. And also, in RM180, BL1029, BM4305, and BMS2055 there were significant differencies of allele frequencies. These results showed a potential application for investigation of putative QTL locations.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.11a
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• pp.187-190
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• 2003

Since the early 1980s, the concept of relationship management in marketing area has gained its importance. Acquiring and retaining the most profitable customers are serious concerns of a company to perform more targeted marketing campaigns. For effective CRM (Customer Relationship Management), it is important to gather information on customer value. Many researches have been performed to calculate customer value based on CLV (Customer Lifetime Value). It, however, has some limitations. It is difficult to consider the churn of customers, because the previous prediction models have focused mainly on expected future cash flow derived from customers'past profit contribution. In this paper we suggest a CLV model considering past profit contribution, potential benefit, and churn probability of a customer. We also cover a framework for analyzing customer value and segmenting customers based on their value. Customer value is classified into three categories: current value, potential value and customer loyalty. Customers are segmented according to the three categories of customer value. A case study on calculating customer value of a wireless communication company will be illustrated.

• Elastomers and Composites
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• v.50 no.4
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• pp.304-313
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• 2015

In this study, the anionic emulsified asphalt was prepared by dispersing asphalt particles evenly into water with combination of anionic and nonionic surfactants. Effects of NaOH and $CaCl_2$ on the phase stability of the emulsified asphalt were also investigated through zeta potential value and rheology behavior; the emulsified asphalt added with NaOH and $CaCl_2$ showed higher zeta potential value than that the asphalt with addition of only anionic and nonionic surfactants. In addition, with regard to shear thinning behaviors, it was found that pH of the emulsified anionic asphalt and $Ca^{2+}$, counter ion, affected the phase stability. SBR (styrene-butadiene-rubber) latex, EPD (water dispersed Epoxy), PU (polyurethane) and RI-10S, SBS (styrene-butadiene-styrene)-based property improvement additive, were used and studied to enhance the adhesion properties with the aggregates. RI-10S, however, was found to be only compatible with the anionic emulsified asphalt; the coating rate, adhesion and compression strength were increased with the RI-10S content.

• Journal of Environmental Science International
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• v.4 no.5
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• pp.469-479
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• 1995

The increase of population and industrial activities had brought into eutrophication in the Nakdong river. A remarkable acceleration of eutrophication brought about serious problems for water supply. Therefore, for the purpose of conservation of water quality in the Nakdong river it is necessary to control nutrients. MBOD method was use to evaluate algal growth limiting factor and algal growth potential in the Nakdong river from June to August 1994. The modified biochemical oxygen demand(MBOD) depends on the amount of available inorganic nutrient and organic substrate during 5 day incubation in the dark at 2$0^{\circ}C$. The MBOD assay depends on inorganic nutrients such as P and N as well as reduced carbon and called the MBOD, the MBOD-P, and the MBOD-N, respectively. The results of bioassay by MBOD(Modified BOD) method showed that the MBOD, MBOD-P and MBOD-N value were found to be in the ranges of 3.8~96.0 mg$O_2$/l, 5.6~94.0 mg$O_2$/l and 42.0~220 mg$O_2$/l, respectively. And the the bioassay value was found to be the highest in Koryong area and the lowest in Waekwan area throughout the Nakdong river. The variations of MBOD-P and MBOD-N value showed similar tendencies to the variations of phosphorus and nitrogen value, respectively. By MBOD method, the relationships of MBOD, MBOD-P and MBOD-N value were MBOD ≒ MBOD-P 《 MBOD-N. The MBOD value was nearly equal to the MBOD-P value, and the MBOD-N value was 3 to 20 times more than the MBOD-P value, approximately. Therefore, in the Nakdong river, phosphorus was the limiting factor for algal growth during summer season. The algal growth potential as the concentration of chlorophyll-a in the summer was maximum 5 times more than standing crop as it.

• Journal of Korean Society of Rural Planning
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• v.14 no.2
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• pp.55-64
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• 2008

This study aims to analyze the sensitivity of WSM(weighted scenario method)-AHP method according to variation of nonlinear exponent for accessibility criteria, which are used to make urbanization potential maps with the optimal weighting value for multiple criteria in grid-based GIS technique. Besides this study tried to develop WSM-AHP2 which is simplified by using rank of the potential value for each scenario. The two methods were applied to the test area, Suwon city located south area of Seoul, with time series land-use maps of 1986 and 1996. The evaluation system of urbanization potential have 7 criteria including 6 accessibility criteria. The results of WSM-AHP2, the optimal weighting values and their corresponding potential maps, have almost similar with those of WSM-AHP. In the application of CA(cellular automata) model for expansion of urbanized area using the three potential maps by WSM-AHP, WSM-AHP2, and specialists's AHP evaluation, it also showed that the accuracy of simulation for actual urban area is the highest in the potential map of WSM-AHP, followed by WSM-AHP2 and specialists's AHP evaluation. From the results of this study, WSM-AHP and simplified WSM-AHP2 will be used to generate the optimal potential maps for land-use planning in urban fringe area.