• Membrane Journal
• /
• v.33 no.4
• /
• pp.191-200
• /
• 2023

Polyethersulfone (PES) is a widely employed membrane material for water and industrial purification applications owing to its hydrophilicity and ease of phase separation. However, PES membranes and filters prepared using the nonsolvent induced phase separation method often encounter significant flux decline due to pore clogging and cake layer formation on the dense membrane surfaces. Our investigation revealed that tight microfiltration or loose ultrafiltration membranes can be subject to physical fouling due to the formation of a dense skin layer on the bottom side caused by water intrusion to the gap between the shrank membrane and the substrate. To investigate the effect of the bottom surface porosity on membrane fouling, two membranes with the same selective layers but different sub-layer structures were prepared using single and double layer casting methods, respectively. The double layered PES membrane with highly porous bottom surface showed high flux and physical fouling tolerance compared to the pristine single layer membrane. This study highlights the importance of physical optimization of the membrane structure to prevent membrane fouling.

• Korean Journal of Culture and Social Issue
• /
• v.23 no.4
• /
• pp.587-604
• /
• 2017

The purpose of this research is to analyze generation gap of positive effects on character strength for full life of adults in Korea and to verify mediating effect of volunteering from character strength in this roots. To test this effects, there was an investigated differences of perception on character strength, volunteering and full life from 1,405 Koreans. Then had set up the influence model of character strength on full life between generation, and verified the model through structural equation. Therethrough first, there was statistical significant between generations except the variables of trust, full life and meaning of life. Second, full life was positively influenced by character strength in early adulthood. Third, volunteering had fully mediated from character strength to full life in post middle aged adults, but had partially mediated in early adulthood. This will help acquaint us with importance of accompany with volunteering at character strength than character strength directly connects to full life. Based on these results, we are treated on importance of mediating volunteering effects and influences of character strengths on full life in Korean society.

• Korean Association of Arts Management
• /
• no.51
• /
• pp.75-102
• /
• 2019

This study aims to figure out the progression of Hyundai motor's corporate cultural marketing by conducting semantic network analysis. Although the previous research has focused on conception, categorization, impact, and performance of cultural marketing, they hardly pay attention to changes in cultural marketing over time. To explore the identified gap, we collected 2,315 articles concerning Hyundai motor's cultural marketing on daily newspapers printed from 2001 to 2018. The 18-year time period was classified into four periods, and lists of words were extracted and analyzed by Korean language analysis program, Textom and social network analysis program, called 'UCINET'. The outcome of our analysis indicates that Hyundai Motor's cultural marketing has been developed from the strategy of merely increasing sales to the means of distinguishing their corporate and brand identity. In the early 2000s, the words 'customer', 'The Age of Great Paintings: Rembrandt and the 17th century Dutch paintings', and 'performances' were extracted with high frequency. It shows Hyundai Motor held performance-oriented events and provided benefits to specific consumer groups under the type of 'Cultural Promotion'. In addition, as the exhibition sponsored by Hyundai motor was reported in the media with high publicity effect, the concept of 'Cultural Support' is also emerged. In the late 2000s, the top exposures were 'Seoul Arts Center' and 'Seoul Metropolitan Symphony Orchestra'. Under the concept of 'Cultural Support', both organizations and cultural events were sponsored by Hyundai motor. Hyundai Motor has the tendency to cooperate with high profile parties who have already accomplished high publicities to attract social interests and issues. In the early 2010s, Hyundai Motor created cultural marketing brand and space ('Brilliant' and 'Hyundai Art Hall') that broadened the potential target groups, which represented both 'Cultural Support' and 'Cultural Enterprise'. In the middle and late of the 2010s, as shown by the high frequency of 'brand' and 'global', Hyundai Motor has focused on the global market and viewpoint has expanded to brand building focusing on the type of 'Cultural Enterprise'.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.28 no.3D
• /
• pp.445-450
• /
• 2008

Recently, environmental and ecological approaches is in progress in urban stream, especially the guarantee of instream flow becomes very important. In this paper, it is suggested that water volume estimation method utilizing the topographical shape data obtained by field investigation and satellite image to manage the urban stream efficiently. The data obtained at Gap River is the study area are analysed and those results are as belows. First, surveying to investigate topographic shape characteristics of urban stream is carried out. In details, the gradient characteristics from water surface to bottom in case of sand area and in case of grass area are 0.013 and 0.065 respectively. In conclusion, the gradient characteristic of grass area is five times bigger than that of sand area. Besides, IKONOS image is classified by spectrum analysis and Minimum Distance Method and the sand area extraction method by the generalization method as Median filter is suggested to calculate water volume. Finally, mapping process on the sand area extracted from the topographical shape field data in river and satellite images is carried out by the GIS spatial analysis. And on the assumption that the water level was 1m at that time when satellite image was taken, the water volume was $225,258m^3$. It is clarified that the effect of water volume improvement was about 10.5% in comparison with water volume that had no consideration on the gradient characteristics of sand-bar.

• Korean Journal of Culture and Social Issue
• /
• v.19 no.2
• /
• pp.87-108
• /
• 2013

With questionnaires conducted for 613 adult Koreans in Seoul, the present study examined how their social features (income level, political party identification, political values, values of capitalism and egalitarianism) exercise influence on attitudes toward income polarization and their evaluation of government policies. Two groups of participants (high vs. low) for each social feature were formed first. Then their attitudes toward income polarization (liberal vs. conservative) and evaluations of policies (liberal vs. conservative) exercised by government (Participatory vs. Practical) were compared. Results indicated that liberal value was strengthened by liberal value, anti-capitalistic, and conservative value was strengthened by egalitarian values, and party identification. It was also found that party identification partial effect on the judgment of policies exercised by Participatory Government. These findings were discussed in terms of their implications for Korean society and measures for communication constructive for settlement of income polarization were suggested.

• Journal of The Korean Association For Science Education
• /
• v.27 no.7
• /
• pp.663-675
• /
• 2007

Chemical reactions in cells are so complicated and abstract that students have difficulty in understanding them. In this study, classes with the application of systematic analogies used at the interpretation of experimental results were taught to 10th-grade students in order to help them to understand the concept of enzymes, which play an important role in chemical reactions in cells. Effects of the classes on their understanding of the concept of enzymes and the role of systematic analogies were analyzed. The gap of understanding between the test group and the control group was significant at 0.05, indicating that systematic analogies are effective for students' understanding of the concept of enzymes. Looking into the concept of enzymes by individual element, the effect of systematic analogies was shown to be large for equilibrium-like processes, such as the enzyme structure change caused by temperature and pH; and the continuous and random actions of enzymes, which students have difficulty in understanding. For these processes, systematic analogies played a positive role in improving their conceptual status. The visualizations and familiarity of analogs increased their intelligibility regarding the concept of enzyme. Also, the systematic analogies increases their plausibility by helping to connect phenomena, taking place in the enzyme reaction experiments, with scientific concepts as scaffold. Accordingly, it was possible to explain experimental results as scientific concepts in a consistent manner. In addition, analogies familiar to students played a positive role from the affective perspective by promoting students' interest and helping them to approach hard scientific concepts.

• Journal of The Korean Association For Science Education
• /
• v.27 no.5
• /
• pp.367-378
• /
• 2007

The purpose of this study is to investigate the features of science language in Earth science textbooks and Earth science research articles. We examined two Earth science textbooks and two Earth science articles using the taxonomy of scientific words, the text structure analysis of explanations, the analysis of conjunctive relations and reasoning, and the function of conjunction. The results showed that school science language revealed in Earth science textbooks had high proportion of naming words and the text structures in which definition/exemplification structure and description structure were dominant. Also, internal relations that showed additional arrangement rather than logical inference, were predominant in Earth science textbooks. However, scientists' science language revealed in the Earth science articles had more proportion of process words and concept words than the Earth science textbooks and the schematic structure of explanation texts, such as orientation - implication sequence - conclusion. In addition, the text structures in each sentences of implication -sequence showed cause/effect or problem-solving after description structures. Also each sentences expressed causal or abductive reasoning through the internal relations using verbs or adverbial inflection. It is necessary that we bridge the gap between the two languages for students' authentic use of science language. For the bridging, we propose "interlanguage", which mediates between school science language and scientists' language.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.37 no.3
• /
• pp.297-303
• /
• 2024

In this study, KTN heterolayer thin films were fabricated by alternately stacking films of K(Ta_0.70Nb_0.30)O₃ and K(Ta_0.55Nb_0.45)O₃ synthesized using the sol-gel method. The sintering temperature and time were 750℃ and 1 hour, respectively. All specimens exhibited a polycrystalline pseudo-cubic crystal structure, with a lattice constant of approximately 0.398 nm. The average grain size was around 130~150 nm, indicating relatively uniform sizes regardless of the number of coatings. The average thickness of a single-coated film was approximately 70 nm. The phase transition temperature of the KTN heterolayer films was found to be approximately 8~12℃. Moreover, the 6-coated KTN heterolayer film displayed an excellent dielectric constant of about 11,000. As the number of coatings increased, and consequently the film thickness, the remanent polarization increased, while the coercive field decreased. The 6-coated KTN heterolayer film exhibited a remanent polarization and coercive field of 11.4 μC/cm² and 69.3 kV/cm at room temperature, respectively. ΔT showed the highest value at a temperature slightly above the Curie temperature, and for the 6-coated KTN heterolayer film, the ΔT and ΔT/ΔE were approximately 1.93 K and 0.128×10^-6 K·m/V around 40℃, respectively.

• Journal of Industrial Convergence
• /
• v.22 no.1
• /
• pp.1-20
• /
• 2024

Regarding the discourse on the correlation between governmental financial support and firm performance, much emphasis has been placed on the role of individual corporate characteristics as well as spatial features. However, there is a notable scarcity of empirical research examining the integrated impact of corporate and cluster characteristics on managerial performance. This study addresses this gap by empirically analyzing the financial and non-financial outcomes resulting from specific allocations of governmental financial support. Additionally, it explores corporate and cluster characteristics predicted to moderate the influence between governmental financial support and firm performance. The analysis employs a two-level hierarchical linear model (HLM) at individual and group levels. The data, reorganized based on business registration numbers at the firm and cluster levels, ultimately utilized panel data from 83,395 firms and 641 clusters. The research findings indicate that governmental financial support demonstrates a positive effect (+) on both sales and patents for firms, suggesting its effectiveness in complementing market failures. Results from the hierarchical linear model analysis show that when combined with human capital capacity, absorptive capacity, and cluster network density, governmental financial support exhibits significant positive effects on sales. This study contributes theoretical and practical insights by analyzing the relationship between governmental financial support and firm performance using a two-level hierarchical linear model. It highlights the role of corporate characteristics such as human capital and absorptive capacity, along with cluster characteristics like cluster network density, in moderating the effects of governmental financial support on firm performance.

• Information Systems Review
• /
• v.19 no.1
• /
• pp.147-168
• /
• 2017

We investigated perceptual similarity and the difference between client and vendor in information technology (IT) outsourcing projects. Specifically, we focused on each player's perception of how the fit of governance and peripheral knowledge affects the performance of IT project outsourcing. For 107 IT projects, we surveyed both client and vendor in the same IT projects and compared the responses of each side. Through a dyadic analysis, we first found that both client and vendor put more weight on the vendor's peripheral knowledge than that of the client as a positive influencer of project performance. However, regarding the governance style of an IT project, client and vendor showed completely different perspectives. The client believed that the vendor's peripheral knowledge positively contributes to the performance of IT project under the governance of outcome control. However, the vendor showed that its peripheral knowledge creates synergy effects under the governance of process control. Our interpretation of the perceptual similarity and difference between client and vendor delivers managerial implications for businesses that process IT projects.