• Korean Journal of Mineralogy and Petrology
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• v.36 no.1
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• pp.19-32
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• 2023

This study was conducted to remove fluorine (F) (initial concentration of 9.5 mg/L) from leachate of reclaimed mine waste dump site via different methods: (1) co-precipitation using Ca-based materials; (2) adsorption using activated carbon and fly ash; and (3) coagulation and sedimentation using alum. The F removal efficiencies of each case were estimated as 65.6% (Ca co-precipitation), 27.9% (adsorption of activated carbon), 71.5% (adsorption of fly ash), and 96.6% (alum coagulation and sedimentation). In addition, the applicability of the continuous treatment process using alum coagulation was evaluated by lab-scale experiments using simulated mine drainage containing F of lower (6.4 mg/L) and higher (15.7 mg/L) concentrations, and it was confirmed that the treatment of both cases met the domestic standard (below 3 mg/L) for discharged water in clean areas. Furthermore, the results of bench-scale field tests indicated that the water quality standard of discharged water could be satisfied with the proper operation and management of the process.

• Knowledge Management Research
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• v.23 no.4
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• pp.275-294
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• 2022

In recent years, with the continuous integrative development of e-commerce and social media, social commerce, as a trust-centered social transaction mode, has become an important performance form of e-commerce. The good experience of online community and abundant user-generated content (UGC) attract more and more users and businesses to participate in the community contribution. In this context, the cost of accessing information is continuously decreasing, which not only makes the purchase process more concise and efficient, but also greatly increases the possibility of consumers' impulsive consumption. However, there are very few empirical studies on the internal influencing mechanism of consumers' impulsive consumption based on the characteristics of UGC for social commerce. In view of this, based on S-O-R model, this study constructs a model of consumers' impulsive consumption in the context of social commerce from the characteristics of UGC, with perceived risk as the mediating variable and tie strength as the moderating variable. The results show that content authenticity, content usefulness, and content valence of UGC have significant negative impacts on consumers' risk perception in the process of purchase decision-making, and consumers' perceived risk has a significant negative impact on consumers' impulsive consumption. Meanwhile, the tie strength between UGC producer and UGC receiver plays a moderating role between content usefulness and perceived risk, as well as between perceived risk and impulsive consumption. Finally, combined with the above findings, this study provides effective suggestions for relevant participants in social commerce in terms of business management.

• Industry Promotion Research
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• v.8 no.3
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• pp.221-230
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• 2023

With the continuous development of higher education, the academic satisfaction of college students has become one of the important indicators to evaluate the quality of education and student development. Therefore, this study aims to explore the role of gender in academic attitude, sincerity, and academic satisfaction of college students in China. The subject of the study was selected by using the purposive sampling method, and data were collected using the survey method. 400 questionnaires were distributed to college students in Guangzhou, China, and 388 questionnaires were used for the final analysis. For statistical analysis, SPSS PC+ Win. ver. 26.0 and SPSS PROCESS macro ver. 4.2 were used, and frequency analysis, reliability analysis, correlation analysis, and conditional indirect effect analysis were performed. The research results are as follows. First, academic attitude had a significant positive correlation with sincerity, gender, and academic satisfaction. Second, gender moderated the intermediary role of academic attitude on academic satisfaction through sincerity. This study indicated that different strategies are needed according to gender to improve academic satisfaction using academic attitude and sincerity of college students. Based on the results, plans to improve the academic satisfaction of college students were suggested.

• Journal of the Daesoon Academy of Sciences
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• v.20
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• pp.169-191
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• 2009

The Four Tenets of Daesoon thought are the Creative conjunction of the virtues of Eum and Yang, the Harmonious union of divine beings and human beings, the Resolution of grievances for the mutual beneficence of all life and the Realization of the Dao in the world. This article compares the concepts of the "Creative conjunction of the virtues of Eum and Yang", the "Harmonious union of divine beings and human beings" and the "Resolution of grievances for the mutual beneficence of all life" with "EumYangDaeDaeRon", "ShinMyonKiDeok", the Theory of Mutual Giving Life / Mutual Destruction (SangSaeng/SangGeukRon) of the Book of Changes and analyzes their common and different points. The conclusion is that Daesoon thought and the philosophy of the Book of Changes share common fundamental standpoints. However, the Daesoon thought defines the world of SeonCheon (the state before the Heaven and Earth have been created) as Mutual Giving Life (SangSaeng), and the world of HuCheon (the state after the Heaven and Earth have been created) as Mutual Destruction (SangGeuk). According to Daesoon thought the Mutual Destruction (SangGeuk) is seen as negative, while according to the philosophy of the Book of Changes the Theory of Mutual Giving Live/Mutual Destruction (SangSaeng/SangGeukRon) is viewed as a positive relationship of EumYangDaeDae. This is a point of difference between the Daesoon thought and the philosophy of the Book of Changes. According to EumYangDaeDae relationship theory the contradictory "other" is viewed not as an enemy, but as a necessary element that assures one's existence. When Buddhism and Christianity first came to existence, they did not belong to a main stream. Later, through continuous theorization and systematization they became generally accepted religions. The case of Confucianism was not much different. During Song dynasty in China Buddhism has contributed to the systematization and establishment of Neo-Confucianism; in the middle of 20th century the Confucian scholars of Hong Kong and Taiwan interpreted and defined Confucianism a new in the light of Western philosophy. Thus the "Modern Neo-Confucianism" came to existence. That's why the history of Confucianism is also called "the history of advancing and developing a concept". From this point of view the critical acceptance of some elements of Confucian, Buddhist, Taoist etc. traditions, as well as modern philosophy, by Daesoon, in order to achieve the systematization of Daesoon thought, is a very important process. As a part of this process, this essay explains the Daesoon thought from the point of view of the Book of Changes, which may be said to present the original East-Asian view of the world. Daesoon's emphasis of human dignity, the equality of sexes, the critics the hierarchical society etc. are rather "modern" and should be examined from the point of view of social science. Besides, leaving the boundaries of "modern philosophy", the concepts of "Harmonious union of divine beings and human beings", viewing the universe as one organism etc. should be approached from the point of view of Post-Modernism.

• Journal of Venture Innovation
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• v.3 no.2
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• pp.23-39
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• 2020

The 4th Industrial Revolution and Covid 19 are moving the fashion industry from offline to online. Fashion shows that took place offline are being replaced by online. Online is greatly increasing consumers' digital customer experience based on digital technologies. In this study, we studied the effect of digital experience factors on digital customer satisfaction based on the Schmitt(1999)'s experience marketing. The effect of digital customer satisfaction on purchase, continuous use intention, and recommendation intention were also studied. In addition, the moderating effect of experience frequency was studied. We randomly sampled 180 individuals among fashion mall users.. SPSS 24, AMOS 23 and Process Macro 3.5 were used for statistical analysis. In the study in which digital experience factors influence digital customer satisfaction, all except the digital act showed positive influence. The impact of influence was digital sense (β = .366) > digital think (β = .225)> digital feel (β = .191) > digital relate(β = .163). Digital customer satisfaction have been positive impact on purchasing, continuance use and recommendation intention. In the moderating effect of digital experience frequency, between digital feel, digital act and digital customer experience showed a statistically effective relationship. Based on the this study, We suggested theoretical and practical implications.

• Journal of Venture Innovation
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• v.5 no.4
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• pp.23-39
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• 2022

This study was conducted to empirically analyze the factors influencing the intention to continue using live commerce, which was active as digital contacts become more prevailed due to the progress of the 4th industrial revolution and the COVID-19 pandemic. A research model was established by paying attention to the characteristics of influencers among various influencing factors. Influencer characteristics were subdivided into attractiveness, professionality, awareness, and entertainment. In addition, the dual mediating effect of interaction and trust was also tested between influencer's characteristics and the intention to continue using of live commerce. To this end, a survey was conducted targeting people who have experience using live commerce, and 300 valid samples were analyzed. The empirical analysis utilized SPSS 25.0 and Process Macro 4.0. As a result of the empirical analysis, it was found that attractiveness, professionality, awareness, and entertainment derived from the characteristics of influencers all had a significant positive (+) effect on the intention to continue using live commerce. The impact of the influence of variables that directly affect the intention to continue using was in the order of entertainment, awareness, professionality, and attractiveness. On the other hand, as a result of examining the dual mediating effect of interaction and trust, it was found that they all tested a mediating role between attractiveness, professionality, awareness, entertainment, and intention to continue using live commerce. Based on these research results, the academic and practical implications of this study were presented.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.5
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• pp.375-387
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• 2023

The subsea power cables are increasingly important for harvesting renewable energies as we develop offshore wind farms located at a long distance from shore. Particularly, the continuous flexural motion of inter-array dynamic power cable of floating offshore wind turbine causes tremendous fatigue damages on the cable. As the subsea power cable consists of the helical structures with various components unlike a mooring line and a steel pipe riser, the fatigue analysis of the cables should be performed using special procedures that consider stick/slip phenomenon. This phenomenon occurs between inner helically wound components when they are tensioned or compressed by environmental loads and the floater motions. In particular, Vortex-induced vibration (VIV) can be generated by currents and have significant impacts on the fatigue life of the cable. In this study, the procedure for VIV fatigue analysis of the dynamic power cable has been established. Additionally, the respective roles of programs employed and required inputs and outputs are explained in detail. Demonstrations of case studies are provided under severely sheared currents to investigate the influences on amplitude variations of dynamic power cables caused by the excitation of high mode numbers. Finally, sensitivity studies have been performed to compare dynamic cable design parameters, specifically, structural damping ratio, higher order harmonics, and lift coefficients tables. In the future, one of the fundamental assumptions to assess the VIV response will be examined in detail, namely a narrow-banded Gaussian process derived from the VIV amplitudes. Although this approach is consistent with current industry standards, the level of consistency and the potential errors between the Gaussian process and the fatigue damage generated from deterministic time-domain results are to be confirmed to verify VIV fatigue analysis procedure for slender marine structures.

• The Korean Journal of Air & Space Law and Policy
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• v.19 no.2
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• pp.97-136
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• 2004

The Northeast Asian air cargo market has expanded tremendously as a result of the opening up of the Chinese market. The importance of the Asia-Pacific region in the global air transport has also increased. The exchange of human and material resources, services, and information in Northeast Asia, which is expected to increase in the near future, requires that the airlines operating within this region adopt a more liberalized approach. This paper introduced alternatives which can be applied to the Northeast Asian airlines industry so as to bring about the integration of regional air transport: First, this paper found a need for individual Northeast Asian nations to alter their policies towards the airlines industry. Second, each country should further liberalize their respective domestic air transport. Third, there is a need for freer air service agreements to be signed between the nations of Northeast Asia. Fourth, the strategic alliances between the airlines operating in Northeast Asia should be further strengthened. Fifth, this liberalization process should be carried out in an incremental manner, beginning with more competitive airports and routes, or with less-in-demand routes. Sixth, there is a need for a shuttle system to be put into place between the main airports in China, Korea, and Japan. Seventh, these three nations jointly develop aviation safety and security systems that are in accordance with international standards. Eighth, the liberalization process of the aviation industry should be undertaken in conjunction with other related fields. Ninth, organizations linking together civil aviation organization in the Asia-Pacific area should be formed, as should each government linking together. By doing so, these countries will be able to establish regular venues through which to exchange opinions on the integration and liberalization of the air cargo market so as to induce the gradual liberalization of the actual market. The liberalization of the air transport in Northeast Asia will prove to be a daunting task in the short term. However, if the Chinese airlines continue to exhibit continuous growth and Japanese airlines are able to complete their move towards a low-cost structure, this process could be completed earlier than expected. Over the last twenty five years the air transport has undergone tremendous changes. The most important factor behind these changes has been the increased liberalization of the market. As a result, rates have decreased while demand has increased. This has resulted in turning the air transport industry, which was long perceived as an industry in decline, into a high-growth industry. The only method of increasing regional exchanges in the air transport is to pursue further liberalization. The country which implements this liberalization process at the earliest date may very well emerge as a leading force within the air transport industry.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.12
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• pp.1280-1286
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• 2006

Three different virgin activated carbons made of each coal(Calgon), coconut(Samchully) and wood(Picabiol) based activated carbon(AC) were tested for an adsorption performance of 1,4-dioxane in a continuous adsorption column. Breakthrough behavior was Investigated that the breakthrough points of coal, coconut and wood based AC were observed as 3600 bed volumn(BV), 1440 BV and 144 BV respectively. Adsorption capacity(X/M) of coal, coconut and wood based AC was observed. The reported results of adsorption capacity showed that coal based AC was highest(578.9 ${\mu}g/g$), coconut based AC was intermediate(142.3 ${\mu}g/g$) and wood based AC was lowest(7.4 ${\mu}g/g$) due to increasing specific surface area. Moreover, carbon usage rates(CURs) for coal, coconut and wood based AC had been shown as 0.48 g/day, 1.41 g/day and 6.9 g/day respectively. The constant characteristic of the system, k of coal based AC was found to be 91.5 and k of coconut based AC was found to be 17.9. Removal efficiencies of 1,4-dioxane with different ozonation dosages(2 and 5 mg/L) for 20 min ozonation had been shown 38% and 87% respectively. There was no observation for biological removal of 1.4-dioxane by attached micro-organisms when used(3.1 years and over 5 years) biological activated carbon(BAC) without pretreatment of oxidation were employed. When a combination of ozonation(2 mg/L and 5 mg/L) and BAC process for $10{\sim}30$ min was applied, removal efficiency for 1,4-dioxine increased only $2{\sim}6%$ compared to only applying ozonation. Therefore removal efficiency of BAC process prior to using oxidation was proven to negligible. Consequently, the results presented in this paper provide a better insight into the adsorption performance of 1,4-dioxane. This observation suggests that using virgin activated carbon made of coal is the best selection for removal of 1,4-dioxane in the water treatment for an advanced treatment. It is clear from this research that longer EBCT for ozonation or higher ozone concentration are more effective operation methods for removal of 1,4-dioxane than longer EBCT in the BAC process.

• Journal of Soil and Groundwater Environment
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• v.11 no.6
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• pp.8-17
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• 2006

Laboratory scale experiments were performed to investigate the removal efficiency of the in-situ chemical oxidation method and the air-sparging method for diesel contaminated soil and groundwater. Two kinds of diesel contaminated soils (TPH concentration : 2,401 mg/kg and 9,551 mg/kg) and groundwater sampled at Busan railroad station were used for the experiments. For batch experiments of chemical oxidation by using 50% hydrogen peroxide solution, TPH concentration of soil decreased to 18% and 15% of initial TPH concentration. For continuous column experiments, more than 70% of initial TPH in soil was removed by using soil flushing with 20% hydrogen peroxide solution, suggesting that most of diesel in soil reacted with hydrogen peroxide and degraded into $CO_2$ or $H_2O$ gases. Batch experiment for the air-sparging method with artificially contaminated groundwater (TPH concentration : 810 mg/L) was performed to evaluate the removal efficiency of the air-sparging method and TPH concentration of groundwater decreased to lower than 5 mg/L (waste water discharge tolerance limit) within 72 hours of air-sparging. For box experiment with diesel contaminated real soil and groundwater, the removal efficiency of air-sparging was very low because of the residual diesel phase existed in soil medium, suggesting that the air-sparging method should be applied to remediate groundwater after the free phase of diesel in soil medium was removed. For the last time, the in-situ box experiment for a unit process mixed the chemical oxidation process with the air-sparging process was performed to remove diesel from soil and groundwater at a time. Soil flushing with 20% hydrogen peroxide solution was applied to diesel contaminated soils in box, and subsequently contaminated groundwater was purified by the air-sparging method. With 23 L of 20% hydrogen peroxide solution and 2,160 L of air-sparging, TPH concentration of soil decreased from 9,551 mg/kg to 390 mg/kg and TPH concentration of groundwater reduced to lower than 5 mg/L. Results suggested that the combination process of the in-situ hydrogen peroxide flushing and the air-sparging has a great possibility to simultaneously remediate fuel contaminated soil and groundwater.