• Korean Chemical Engineering Research
• /
• v.61 no.3
• /
• pp.378-387
• /
• 2023

Petrochemical is an energy consuming industry that consumes about 30% of total industrial energy consumption and is a representative carbon dioxide (CO₂) emission source. Among them, the Naphtha Cracking Center (NCC), which produces ethylene, propylene, propane and mixed C4, consumes large amounts of energy and emits significant amounts of CO₂. For this reason, an integrated techno economic- environmental impact assessment aimed at reducing energy consumption and environmental impact factors is necessary to ensure efficiency in terms of economics and environment. This study aims to analyze the efficiency of the heat exchanger network used in the existing NCC base on the pinch analysis and select an improvement plan that can reduced energy consumption. In order to reduces the utility consumption in the process, an optimal heat exchanger network considering the high-temperature and low-temperature stream was derived, and the economic evaluation was conducted by considering the trade-off between the reduction in utility consumption and the increase in heat exchanger installation cost. In addition, an environmental impact assessment was conducted on the reduced CO₂ emission in consideration of the environmental aspect, and the economic environmental impact assessment used the payback period to recover the invested funds to come up with an energy saving plan that can be applied based on the actual process. As a result of considering the economic-environmental impact assessment, when the environmental impact assessment was not considered, it was 4.29 months, 3.21 months, and 3.39 months for each case, and when considering the environmental impact assessment, it was 4.24 months, 3.17 months, and 3.35 months for each case. These results appeared equally both when the environmental impact assessment was not include and when it was include. In addition, a sensitivity analysis was conducted for each case to determine how important factors affect the payback period. As a result of the sensitivity analysis, the cost of the heat exchanger was identified as a major factor influencing the overall cost.

• Journal of the Korean Society of Radiology
• /
• v.16 no.4
• /
• pp.427-434
• /
• 2022

Atrial fibrillation treatment includes 3D RFCA and Cryo-balloon ablation. Both procedures have in common that they enter after understanding the structure of the heart using angiography equipment. Therefore, there is a disadvantage that the effect of exposure according to the procedure time can be a threat to both the patient and the operator, so this study aims to confirm the relationship between the total ablation time and the effect of radiation exposure. We used follow-up data (retrospective) from 41 patients who underwent coronary angiography and arrhythmia at the same time from March 2019 to July 2022. The range for total ablation time was based on the recorded data from the start to the end of the total ablation. The end point of 3D RFCA was when the ablation was completed for 4 pulmonary veins, and in the case of Cryo-balloon ablation, the data that succeeded in electrical insulation were included. As a result of analyzing the total ablation time, the time taken for Cryo-balloon ablation was 1037.29±103.66 s, which was 2448.61 s faster than 3D RFCA using 3485.9±405.71 s, and was statistically significant. (p<0.05) As a result of analyzing the total fluoroscopy time, the exposure time for 3D RFCA was 2573.75±239.08 s, which was less by 1717.15 s than the exposure time for Cryo-balloon ablation, 4290.9±420.42 s, and was statistically significant. In the case of total area dose product, 3D RFCA was 59.04±13.1 uGy/m², which was lower than Cryo-balloon ablation 980.6±658.07 uGy/m² by 921.56 uGy/m², which was statistically significant. As the insulation time of the Cryo-balloon ablation is shorter than that of the 3D RFCA, the method using the Cryo-balloon ablation is considered to be effective when the patient's condition is not good and a quick procedure is required. However, in patients with permanent Atrial fibrillation, there is a high probability of structural changes in the heart, so it is considered that 3D RFCA is better than Cryo-balloon ablation, which is difficult to manipulate.

• Journal of Environmental Impact Assessment
• /
• v.32 no.3
• /
• pp.166-175
• /
• 2023

This study aims to identify the cause of the red-water occurrence (the phenomenon of water being red) that occurs at some points and sections of rivers in Yongin City. As a result of conducting a preliminary investigation, total three sites were selected as the investigation point as it was found that the red-water occurrence continued. As a result of the investigation, it is judged that the cause of the red-water in Yongin-city river is due to the soil color and iron content of the region. JPS, SBS, and JJS sites all showed that the color of soil is mainly consist of reddish brown and red-yellow. The average Fe concentration was 13.75 mg/L, 10.85 mg/L, and 1.31 mg/L, for each sites, and considering that the Fe concentration in general river water was less than 0.5 mg/L, it was confirmed that the concentration was quite high. At the JPS and JJS points, the red-water occurrence occurred mainly in stagnant places, which is believed to be strengthened by the reaction of organic and microorganisms. In the case of SBS, the wateris red, but as a result of observing the actual color, it is judged that the iron component deposited in the pipe causes an optical illusion with a deep red color. In addition, it is believed that the iron concentration can be reduced to the general river water concentration range by removing the particulate iron component through a decrease of more than 95% as a result of filtering with glass fiber filter with particulate iron. As a result of this study, it is necessary to manage the river to maintain the flow, and it is believed that the occurrence of red-water at the survey point can be alleviated through uptake action through planting and agglomeration precipitation and agglomeration filtration methods for particulate iron treatment.

• Knowledge Management Research
• /
• v.24 no.2
• /
• pp.241-262
• /
• 2023

The phenomena and game records that occur in sports matches are being analyzed in the field of sports game analysis, utilizing advanced technologies and various scientific analysis methods. Among these methods, social network analysis is actively employed in analyzing pass networks. As football is a representative sport in which the game unfolds through player interactions, efforts are being made to provide new insights into the game using social network analysis, which were previously unattainable. Consequently, this study aims to analyze the changes in pass networks over time for a specific football team and compare them in different scenarios, including variations in the game's nature (Qatar World Cup games vs. A match games) and alterations in the opposing team (higher FIFA rankers vs. lower FIFA rankers). To elaborate, we selected ten matches from the games of the Korean national football team following Coach Bento's appointment, extracted network indicators for these matches, and applied four indicators (efficiency, cohesion, vulnerability, and activity/leadership) from a football team's performance evaluation model to the extracted data for analysis under different circumstances. The research findings revealed a significant increase in cohesion and a substantial decrease in vulnerability during the analysis of game performance over time. In the comparative analysis based on changes in the game's nature, Qatar World Cup matches exhibited superior performance across all aspects of the evaluation model compared to A matches. Lastly, in the comparative analysis considering the variations in the opposing team, matches against lower FIFA rankers displayed superior performance in all aspects of the evaluation model in comparison to matches against top FIFA rankers. We hope that the outcomes of this study can serve as essential foundational data for the selection of football team coaches and the development of game strategies, thereby contributing to the enhancement of the team's performance.

• Journal of Christian Education in Korea
• /
• v.74
• /
• pp.7-31
• /
• 2023

The climate crisis threatens Earth's ecosystems and biodiversity. In particular, it can be said that the cause of the global crisis began with human greed. An educational alternative is needed to change the Christian worldview that causes greed. The purpose of this study is to find ways to apply democratic citizenship education to Christian education as an alternative to overcome the climate crisis. The contents of the study to achieve the purpose were first the essence of Christian citizenship education was examined by dividing it into citizenship education, democratic citizenship education, and Christian citizenship education. Second, The model of democratic citizenship education was established by defining its goals, content, methods, and directions within the context of Christian citizenship education. Third, the application plan of Christian education for democratic citizenship education was classified into 7 categories and proposed; environmental education to overcome the climate crisis, ethical education to restore the public role of the church, education to form God's character, education to realize the village education community, education that promotes Christ's peace and Christ education that fosters consideration for multicultural individuals, and literacy education to prevent the negative impacts of digital media culture. Next, the plan to apply democratic citizenship education to Christian education is, first, to reduce human greed and restore God's creation order through environmental education that can overcome the climate crisis. Second, through ethics education to restore the church's public nature, it is necessary to restore the church's role for the church's moral empathy and publicity. Third, through the education that forms the God's character, it is necessary to form a mature character of faith in which personality and faith are harmonious and balanced. Fourth, schools, villages, and churches form a community through education that realizes a village education community so that the members of the village can obtain educational results. Fifth, through education that aims for the peace of the God Christians should be able to live as Christian democratic citizens who achieve peace in the kingdom of God. Sixth, through education that considers multicultural people, faith education that helps them overcome discrimination, exclusion, and hatred toward multicultural people with the love of Jesus Christ and seek a life of coexistence. Seventh, through literacy education that prevents the harmful effects of digital media culture, personal ability to read and write in media should ultimately be improved to the ability to practice socially.

• The Korean Journal of Franchise Management
• /
• v.5 no.1
• /
• pp.27-47
• /
• 2014

This research was conducted on the purpose of seeking the measures of how to cope with the changing industry of Topokki franchises. Despite of the fact the number of Kukdae Topokki's stores is quite smaller than that of its competitors, such as Jaws Topokki and Addal Topokki, Kukdae Topokki is recognized as one of the front-runners in the industry. But the competition in the topokki industry has become fiercer, as the market became saturated. To find a desirable solutions, this study analyzes past-to-current status of the Topokki industry by dividing it into 4 stages and provides few strategies that Kukdae Topokki can apply to the 4th stage where 'brand awareness' is very important. To this end, few drawbacks of Kukdae Topokki are proposed as the following. First, the brand image that Kukdae Topokki pursue does not correspondent with the image in consumer's mind. Second, Kukdae Topokki has selected the wrong targeting group. It aims for the image of 'retro' to target people in their 30-40s. However, most of the consumers are people in their 20-30s. Third, the taste of Kukdae Topokki is not uniform among franchises. Fourth, the awareness and accessability are low. To provide a proactive actions for the next stages, several solutions are proposed as following. First, By managing consistent Kukdae Topokki's Brand Touch point, consumers may have a strong image on the brand by communicating with consumers consistently at all touch points. Second, instead of the existing guide from the head office(franchiser), a standardized criteria for the usage of materials and periodical education for franchisee are needed. Third, to raise the awareness of Kukdae Topokki, open many branches in the area where the main consumers(20-30s women) are mostly spread out.

• Korean Journal of Plant Resources
• /
• v.36 no.4
• /
• pp.413-434
• /
• 2023

Sesame (Sesamum indicum L.) is an ancient oilseed crop, which is usually cultivated for its seeds. Sesame breeding aims to achieve high seed yield and quality, along with resistance to biotic or abiotic stresses. It is estimated that sesame is originated from Asia or Africa continent. In this study, we characterized 10 agronomic traits and evaluated lignan contents in 165 sesame germplasm originated from Asia or Africa, to select high-yield or high-lignan content accessions. Sesame germplasm showed diverse phenotypes and highly variable lignan contents (sesamin: 0.5-12.6 mg/g, sesamolin: 0.1-3.5 mg/g, lignan: 1.1-16.1 mg/g). Based on originated continent, there are significant difference in agronomic traits, but no in lignan content. Correlation analysis revealed that yield-related agronomic traits were negatively related with lignan contents. Also, PCA analysis showed that most agronomic traits and lignan contents were principal components explaining diversity of whole sesame germplasm. Sesame germplasm was clustered into three groups based on agronomic traits and lignan contents. Finally, we selected high-yield (IT29416, IT167042, K276848, K276849) and high-lignan candidate accessions (IT169254, IT170031, IT169250, IT154876, IT170034), respectively. These accessions are expected to be valuable resources for breeding of high-yield and high-lignan contents functional cultivars.

• Journal of Service Research and Studies
• /
• v.11 no.2
• /
• pp.37-66
• /
• 2021

This study aims to provide self-development opportunities to hair salons service workers through e-learning and provide the foundation of sustainable hair salons management by cultivating good talents to hair salons service business executives. In particular, the factors affecting e-learning achievement are identified according to learner characteristics to see whether these factors affect the satisfaction of e-learning learners and also affect the performance of management. The results of the study are summarized as follows. As a result of hypotheses testing on the relationship between e-learning learning environment and e-learning satisfaction, it was found that the higher the level of e-learning content quality is, the higher the satisfaction of e-learning is, the higher the satisfaction of e-learning is, and that the higher the quality level of the support infrastructure is, the higher the satisfaction of e-learning is. The results of the hypotheses testing on the moderating effect of learner factors showed that the influence of the quality of the support infrastructure on the e-learning satisfaction differs according to the level of the learner's goal consciousness. However, it was found that the influence of content quality on e-learning satisfaction according to the level of the learners goal awareness, the influence of content quality on e-learning satisfaction according to the level of the aggressiveness of the learners learning attitude, and the influence of the quality of the support infrastructure on the e-learning satisfaction according to the level of the aggressiveness of learners learning attitude were found to identically demonstrate no moderating effects. The results of hypotheses testing on the relationships among e-Learning performance show that the higher the satisfaction of e-learning was, the higher the customer orientation was, and the higher the satisfaction of e-learning was, the higher the contribution of management performance was, and the higher the customer orientation was, the higher the contribution of management performance was. The implications of this study are as follows. First, the actual path of realiting e-learning performance could be identified that is this study provided organizational decision makers involved in the hair salons service operations with practical guidance for the introduction and expansion of successful educational systems. Second, the e-learning environment derived from the theoretical background is different from the e-learning environment required by the learners.

• Journal of Navigation and Port Research
• /
• v.47 no.3
• /
• pp.147-154
• /
• 2023

This study aims to determine the necessity, role, utilization, and operation and management plan in relation to the underwater space platform where humans can newly reside. It provides a comprehensive opinion on the need for creating undersea space and operation plans based on opinions of industry-university-affiliated organizations involved in the R&D project of the Ministry of Maritime Affairs and Fisheries for the utilization of undersea space and external experts participating in marine technology development. In this study, a survey was conducted on researchers participating in the construction of a Korean submarine space platform. FGI was conducted on marine technology development experts. Results were then derived. As a result of the analysis, the need for subsea space construction was found to be high. As for the role of subsea space, the most common opinion was to develop technology for utilizing subsea space and to secure marine science research functions. It was found that the creation of subsea space would have a positive impact on the domestic industry, especially the deep-sea development industry and the shipbuilding/offshore structure industry. In terms of utilization, after the end of the seabed space test bed, the response to utilization as a marine observation base and marine ecosystem research had the highest proportion. As for expected inconvenience, discomfort in the psychological environment was the highest. Experts suggest that securing a continuous budget is most important for stable operation in the future and that securing a manpower budget is essential for itemized budgets. In addition, it was judged that it would be appropriate to establish a prior agreement from the time of the prior agreement and prepare a countermeasure before proceeding with the project in order to ensure ownership issues, consignment management issues, and cost issues when using the project after the end of the project.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.29 no.4
• /
• pp.297-306
• /
• 2023

Saemangeum Lake is the largest artificial lake in Korea. The continuous deterioration of lake water quality necessitates the introduction of novel water quality management strategies. Therefore, this study aims to identify the spatiotemporal water quality characteristics of Saemangeum Lake using data from the National Water Quality Measurement Network and provide basic information for water quality management. In the water quality parameters of Saemangeum Lake, water temperature and total phosphorous content were correlated, and salt, total nitrogen content, pH, and chemical oxygen demand were significantly correlated. Other parameters showed a low correlation. The spatial principal component analysis of Saemangeum Lake showed the characteristics of its four zones. The mid-to-downstream section of the river affected by freshwater inflow showed a high nutrient salt concentration, and the deep-water section of the drainage gate and the lake affected by seawater showed a high salt concentration. Two types of water qualities were observed in the intermediate water area where river water and outer sea water were mixed: waters with relatively low salt and high chemical oxygen demand, and waters with relatively low salt and high pH concentration. In the principal component analysis by time, the water quality was divided into four groups based on the observation month. Group I occurred during May and June in late spring and early summer, Group II was in early spring (March-April) and late autumn (November-December), Group III was in winter (January-February), and Group IV was in summer (July-October) during high temperatures. The water quality characteristics of Saemangeum Lake were found to be affected by the inflow of the upper Mangyeong and Dongjin rivers, and the seawater through the Garuk and Shinshi gates installed in the Saemangeum Embankment. In order to achieve the target water quality of Saemangeum Lake, it is necessary to establish water quality management measures for Saemangeum Lake along with pollution source management measures in the upper basin.