• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.6
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• pp.562-575
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• 2023

In an effort to improve water quality, the South Korean government has implemented measures to increase seawater circulation in Saemangeum Lake. We analyzed the effect of increasing the frequency of seawater circulation based on salinity levels and bottom water exchange in the lake, using an environmental fluid dynamics code model. When the sluice gate opening and shutting frequency increased from once to twice per day, the internal water level of Saemangeum Lake increased by up to ~0.7 m. The salinity increased by 2.12 psu near the western breakwater and decreased by 1.18 psu near the freshwater inlet. We analyzed the extent of bottom water exchange using a particle tracing method and observed that the residual rate of particles shallower than 5 m in water depth decreased by 2.52% in Case 2 (opening and shutting twice per day) compared to Case 1 (opening and shutting once per day). This indicates that increasing the frequency of sluice gate opening and shutting would promote enhanced bottom water exchange. Consequently, the increased salinity and bottom water exchange associated with increased seawater circulation are expected to improve water quality in Saemangeum Lake.

• Journal of the Korean Geotechnical Society
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• v.39 no.12
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• pp.61-73
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• 2023

Suction buckets are feasible options for offshore foundations to support subsea structures in deep water, enabling suction-induced installation by pumps. Recently, hybrid suction bucket foundations that combine single or multiple suction buckets with a mat foundation have been considered. The foundations effectively increase the load capacity while reducing construction costs. However, there is still insufficient experimental validation of hybrid suction bucket foundations regarding their bearing capacity. Furthermore, research on the horizontal load capacity under low vertical and moment loads is inadequate. In this study, we investigate the feasibility of using a hybrid suction bucket foundation for subsea installations in clay. We considered two types of hybrid suction bucket foundations: a circular mat with a single suction bucket and a square mat with multiple buckets. Centrifuge tests were performed to understand the hybrid suction bucket foundation characteristics under horizontal loads and their corresponding bearing capacity. Particularly, we verified the effect of the mat foundation and bucket embedment depth on the horizontal bearing mechanism and capacities. Results confirmed that the hybrid suction bucket foundation outperforms the single suction bucket.

• Information Systems Review
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• v.21 no.1
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• pp.39-59
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• 2019

E-learning has improved the educational effect by making it possible to learn anytime and anywhere by escaping the traditional infusion education. As the use of e-learning system increases with the increasing popularity of e-learning, it has become important to measure e-learning satisfaction. In this study, we used the mixed research method to identify satisfaction factors of e-learning. The mixed research method is to perform both qualitative research and quantitative research at the same time. As a quantitative research, we collected reviews in Udemy.com by text mining. Then we classified high and low rated lectures and applied topic modeling technique to derive factors from reviews. Also, this study conducted an in-depth 1:1 interview on e-learning learners as a qualitative research. By combining these results, we were able to derive factors of e-learning satisfaction and dissatisfaction. Based on these factors, we suggested ways to improve e-learning satisfaction. In contrast to the fact that survey-based research was mainly conducted in the past, this study collects actual data by text mining. The academic significance of this study is that the results of the topic modeling are combined with the factor based on the information system success model.

• Journal of the Korean Society for information Management
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• v.41 no.3
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• pp.205-247
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• 2024

The purpose of this study is to investigate how information use behavior and satisfaction appear by personality type for liberal arts learning among college students, and to propose a customized information service plan that can help college students study in university libraries. To this end, a survey was conducted on 169 university students enrolled in C University. The analysis consisted of demographic characteristics, MBTI personality type, information use behavior, satisfaction, and university library service perception survey. Frequency analysis, cross-analysis, multinomial logistic regression, one-way ANOVA, and hierarchical regression analysis were performed on the collected data using the SPSS 29 statistical program. As a result of the study, first, significant results were found in 'preferred information sources', 'information source consideration factors', and 'information collection patterns' according to personality type. Second, there were statistically significant differences in satisfaction according to personality type in 'system utilization ability', 'data selection ability', and 'the degree of recognition of the usefulness of learning activities'. Third, in the relationship between preferred information sources and satisfaction based on personality types and information use behaviors, there appears to be an inverse relationship when the content includes various topics with a lack of academic depth or expertise. However, the preference for 'social media' is positively correlated with 'satisfaction with search results,' as it provides diverse perspectives and viewpoints in liberal education

• Journal of Korean Home Economics Education Association
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• v.35 no.4
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• pp.47-60
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• 2023

The purpose of this study was to examine students' experiences in the dietary life class using traditional Korean desserts in middle school home economics classes. Participatory observation, in-depth interview, and site data collected in this study were analyzed through emic coding, and the results are as follows. First, students had 'expectations about Han-gwa lab classes.' Students were always positive about lab classes, looking forward to eating delicious food and eagerly awaiting their first lab class since entering middle school. Additionally, there were many students who were experiencing Han-gwa for the first time, so expectations about learning about Han-gwa were high. Second, students engaged in 'self-directed learning through the Han-gwa project.' In other words, while creating an activity book about Han-gwa, the students realized self-directed learning about the differences between Han-gwa and Yang-gwa (Western-style sweets), and the scientific principles of cooking Han-gwa. Third, students had 'instilled pride in Han-gwa through lab classes.' The students learned that there was sufficient awareness and change in values to cherish Han-gwa and to inherit its traditions. Fourth, there was a 'potential curriculum effect.' Students who did not experience face-to-face group activities for three years in middle school due to COVID-19 came to recognize the importance of collaboration and even tried making Han-gwa at home. In order for students to have pride in Han-gwa, it was confirmed that it was necessary for home economics teachers at school to actively teach classes on traditional foods and provide students with many opportunities to encounter them.

• Journal of Naturopathy
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• v.12 no.2
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• pp.45-55
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• 2023

Background: A musical self-care program can be used to prevent physical and psychological burnout of social workers in child care facilities. Purpose: This study aims to find out what social workers at child care facilities experience and mean by musical self-care, and what the benefits of using music are in self-care cases. Method: Qualitative case study method was applied and explored. Five sessions of a musical self-care program and one session of face-to-face in-depth interviews were conducted with four child care facility social workers from April 2022 to June 2022, and the data were analyzed as a collective case study and the results were obtained. Results: The musical self-care experiences of the participants were analysed into two major perspectives. The first is reflection in the care process. The second result is the benefit of using music in the care process. The need for self-care by social workers at child care facilities was confirmed, and that among various methods of self-care, the self-care process using music had a positive effect. In the musical self-care process, the intervention of music is based on the individual's self-reflection and self-acceptance, obtains psychological rewards through communication between colleagues, helps psychological recovery, and forms a cooperative relationship. Conclusion: This study indicates the need for musical self-care for social workers in child care facilities and provides implications that examples of its application in social welfare settings are important.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.50 no.3
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• pp.201-211
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• 2024

The aim of this study was to propose Rosa multiflora (R. multiflora) as a cosmetic material for refining pores, and the ethanolic extract of R. multiflora (RME) was used to identify changes in various factors related to sebum regulation, astringency, and extracellular matrix, which are known to affect pores, and the effects were confirmed through clinical trials. The effects of these changes were confirmed through clinical trials. As a result, RME suppresses the excessive production of sebum, and it possesses DPPH radical scavenging ability through an astringent tannin component. Futhermore, RME inhibited 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) activity and matrix metalloproteinase-1 (MMP-1) production, and it increased hyaluronic acid synthesis. In clinical trials, it was confirmed that RME significantly reduced the area, depth, number, volume, and density of pores-key parameters for assessing pores-and it also reduced sebum levels. This suggests that RME has an astringent effect and could be used as a cosmetic ingredient to improve the appearance of pores by controlling sebum production and influencing ECM-related factors.

• Journal of Distribution Research
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• v.17 no.1
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• pp.87-115
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• 2012

Introduction: In these days, a loyalty program is one of the most common marketing mechanisms (Lacey & Sneath, 2006; Nues & Dreze, 2006; Uncles et al., 20003). In recent years, Coalition Loyalty Program is more noticeable as one of progressed forms. In the past, loyalty program was operating independently by single product brand or single retail channel brand. Now, companies using Coalition Loyalty Program share their programs as one single service and companies to participate to this program continue to have benefits from their existing program as well as positive spillover effect from the other participating network companies. Instead of consumers to earn or spend points from single retail channel or brand, consumers will have more opportunities to utilize their points and be able to purchase other participating companies products. Issues that are related to form of loyalty programs are essentially connected with consumers' perceived view on convenience of using its program. This can be a problem for distribution companies' strategic marketing plan. Although Coalition Loyalty Program is popular corporate marketing strategy to most companies, only few researches have been published. However, compared to independent loyalty program, coalition loyalty program operated by third parties of partnership has following conditions: Companies cannot autonomously modify structures of program for individual companies' benefits, and there is no guarantee to operate and to participate its program continuously by signing a contract. Thus, it is important to conduct the study on how coalition loyalty program affects companies' success and its process as much as conducting the study on effects of independent program. This study will complement the lack of coalition loyalty program study. The purpose of this study is to find out how consumer loyalty affects affiliated brands, its cause and mechanism. The past study about loyalty program only provided the variation of performance analysis, but this study will specifically focus on causes of results. In order to do these, this study is designed and to verify three primary objects as following; First, based on opinions of Switching Barriers (Fornell, 1992; Ping, 1993; Jones, et at., 2000) about causes of loyalty of coalition brand, 'brand attractiveness' and 'brand switching cost' are antecedents and causes of change in 'brand loyalty' will be investigated. Second, influence of consumers' perception and attitude prior to joining coalition loyalty program, influence of program in retail brands, brand attractiveness and spillover effect of switching cost after joining coalition program will be verified. Finally, the study will apply 'prior brand preference' as a variable and will provide a relationship between effects of coalition loyalty program and prior preference level. Hypothesis Hypothesis 1. After joining coalition loyalty program, more preferred brand (compared to less preferred brand) will increase influence on brand attractiveness to brand loyalty. Hypothesis 2. After joining coalition loyalty program, less preferred brand (compared to more preferred brand) will increase influence on brand switching cost to brand loyalty. Hypothesis 3. (1)Brand attractiveness and (2)brand switching cost of more preferred brand (before joining the coalition loyalty program) will influence more positive effects from (1)program attractiveness and (2)program switching cost of coalition loyalty program (after joining) than less preferred brand. Hypothesis 4. After joining coalition loyalty program, (1)brand attractiveness and (2)brand switching cost of more preferred brand will receive more positive impacts from (1)program attractiveness and (2)program switching cost of coalition loyalty program than less preferred brand. Hypothesis 5. After joining coalition loyalty program, (1)brand attractiveness and (2)brand switching cost of more preferred brand will receive less impacts from (1)brand attractiveness and (2)brand switching cost of different brands (having different preference level), which joined simultaneously, than less preferred brand. Method : In order to validate hypotheses, this study will apply experimental method throughout virtual scenario of coalition loyalty program if consumers have used or available for the actual brands. The experiment is conducted twice to participants. In a first experiment, the study will provide six coalition brands which are already selected based on prior research. The survey asked each brand attractiveness, switching cost, and loyalty after they choose high preference brand and low preference brand. One hour break was provided prior to the second experiment. In a second experiment, virtual coalition loyalty program "SaveBag" was introduced to participants. Participants were informed that "SaveBag" will be new alliance with six coalition brands from the first experiment. Brand attractiveness and switching cost about coalition program were measured and brand attractiveness and switching cost of high preference brand and low preference brand were measured as same method of first experiment. Limitation and future research This study shows limitations of effects of coalition loyalty program by using virtual scenario instead of actual research. Thus, future study should compare and analyze CLP panel data to provide more in-depth information. In addition, this study only proved the effectiveness of coalition loyalty program. However, there are two types of loyalty program, which are Single and Coalition, and success of coalition loyalty program will be dependent on market brand power and prior customer attitude. Therefore, it will be interesting to compare effects of two programs in the future.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.5
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• pp.137-145
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• 2008

In this study, to reduce the flood damage caused by flood discharge exceeding project flood, the primary technology was applied to determining the optimal location and size for underground sluiceway. The Jungrang Stream was selected for this study because the stream was overflowed and the embankment section of the stream was destroyed owing to localized torrential rainfall in 1998 and 2001. Considering 200-year frequency storm, the inlets of the underground discharge channel were located at Seoul City limits, the confluence of Danghyun Stream, Wolgye 1-gyo, and the confluence of Mukdong Stream. The outlets were located at the estuary of Jungrang Stream and rightbank of Banpo Bridge in Han River. The transverse discharge according to the variation of overflow depth at the inlet of underground discharge channel was estimated and the effect of inundation reduction was analyzed. To examine the appropriate scale of the underground discharge channel, the 8 operation methods for the management of outlet discharge were compared considering four rules (only storage, the constant discharge rate, the constant discharge volume, and the mixture of the constant discharge rate and discharge volume). As a result, the effect of inundation reduction was most significantly improved when the inlet was located at the confluence of Danghyun Stream. The appropriate size of underground sluiceway for 200-year frequency storm was studied, and as a result, the appropriate diameters of the underground discharge channel were 12 m in case of only storage(Rule D), 9m in 50% of discharge(Rule E), 8 m in constant discharge volume(Rule F), and 7 m in mixture method(Rule G). This investigation process can be applied to design the underground discharge channel when the inundation damage is significant in coastal area due to embankment overflow. The underground discharge channel in Jungrang Stream can also be used as an underground road to link Seoul City to Uijeongbu City during dry season.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.3
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• pp.285-294
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• 2003

To select an appropriate sampler for the environmental monitoring survey in coastal waters of Saemangeum, Jeollabuk-do, a macrobenthic sampling was conducted in April 2002. Employed samplers were dredge (type Charcot), a semi-quantitative sampler and Smith-McIntyre (SM) and van Veen grab (VV) as quantitative ones. One haul was tried for dredge and 3 replicates (0.1 ㎡${\times}$3) for SM and W at each of 11 stations. Comparisons of sediment volume in sampler bucket and of precision of biological parameters (i.e., density, biomass, species number and diversity index, H') were made between SM and VV. Sediment volume was significantly different (SM > VV) at p-value of 0.0050 (paired t-test) and, in average, 3 replicate samples of SM and VV satisfied a precision level of 0.2 by applying 4th root transformation. Patterns of observed and expected species numbers and H' were compared. Dredge-VV samples showed higher affinity than any other pair. Several dominant species in the area were underestimated in dredge samples (e.g., polychaete Heteromastus filiformis. Aricidea assimilis etc.). Quantifying the agreement pattern of multi-species responses was accomplished by estimating correlations between similarity matrices. Correlation between dredge and VV was slightly higher, but near-per-fect matches were found in general. Different ranks and composition among principal species lists were presumably linked to the effect of penetration depth that differs among samplers. Lower level of some species' abundance in VV samples (ca. 50％ compared with those of SM) was explained in this context. It seem appropriate to regard the effect as a probable cause of relatively higher correlations in dredge-VV, Overall bio-logica1 features indicated that a better choice could be SM in situations of requiring high data quality. The others work well, however, on observing and defining faunal characteristics and their capability cannot be questionted if we do not expect a first-order quality.