• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.6 no.3
• /
• pp.431-438
• /
• 1996

Transmission electron microscopy has been used to investigate the microstructure of hot-pressed $TiB_{2}$. Thin foil specimens, prepared by conventional ion beam thinning, revealed many features which originated from the crystallographic anisotropy of hexagonal $TiB_{2}$. It was observed that in these specimens Fe-impurities are precipitated to form secondary Fe-rich phases at grain triple edges, in grain boundaries and sometimes in-grain. These Fe-rich precipitates were characterised by their coherence or semi-coherence to a favourably oriented grain at a grain triple edge or grain boundaries or to the matrix $TiB_{2}$ phase.

• Membrane Journal
• /
• v.34 no.3
• /
• pp.192-203
• /
• 2024

The advancement of commercially viable gas separation membranes plays a pivotal role in improving CO₂ separation efficiency. High-molecular-weight poly(ethylene oxide) (high-Mw PEO) emerges as a promising option due to its high CO₂ solubility, affordability, and robust mechanical attributes. However, the crystalline nature of high-Mw PEO hinders its application in gas separation membranes. This study proposes a straightforward blending approach by incorporating various polymeric additives into high-Mw PEO to address this challenge. Four commercially available, water-soluble polymers, i.e. poly(ethylene glycol) (PEG), poly(propylene glycol) (PPG), poly(acrylic acid) (PAA), and poly(vinyl pyrrolidone) (PVP) are examined as additives to enhance membrane performance by improving miscibility and reducing PEO crystallinity. Contrary to expectations, PEG and PPG fail to inhibit the crystalline structure of PEO and result in membrane flaws. Conversely, PAA and PVP demonstrate greater success in altering the crystal structure of PEO, yielding defect-free membranes. A thorough investigation delves into the correlation between changes in the crystalline structure of high-Mw PEO blend membranes and their gas separation performance. Drawing from our findings and previously documented outcomes, we offer insights into designing and selecting additive polymers for high-Mw PEO, aiming at the creation of cost-effective, commercially viable CO₂ separation membranes.

• Korean Journal of Construction Engineering and Management
• /
• v.17 no.3
• /
• pp.108-115
• /
• 2016

The price determinant for land investment depends on the internal information process and subjective decision making by management in general. Accordingly, the systematic frame to determine the feasibility of investment price to the public residential land for multi-housing development by private sector has not been proposed. The purpose of this study is to explore the frame to determine the investment price for public residential land from the perspectives of land attribute and apartment market factor. Multiple regression has been implemented to confirm the eligibility of proposed model. Research findings indicate that the land area, floor area ratio, coverage ratio, location have been identified as the total land cost determinant, and for the determinants for floor area land cost, the ratio of apartment, sale price, rent price, etc, have been identified. This research intends to provide the basis for land providers to predict the land value as a raw material in market and present the indicators for land buyers to review the price adequacy for the investment.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.33 no.2
• /
• pp.679-689
• /
• 2013

To relieve Green-house Gas Emission is the key issue in urban area. Urban transport policies have focused on the reduction of private car use. The most common of these is Travel Demand Management(e.g., congestion charge, environmental tax, etc.) that forces individuals to reduce their private car use. An alternative way is Mobility Management(MM) that induces individuals to voluntarily change their car use through communications. MM is founded on social psychology theory and focuses on individuals' decision making processes to change their perception and attitude on private car use. Although some researchers have reported the relevance of MM approach, still few researches have explicitly studied on individuals' decision making processes. Therefore, the aims of the paper are to analyze the decision making process of individuals and to provide the basis of introducing MM approach in Korea. Structural equation model(SEM) is applied for the analysis of individuals' decision making process. A empirical study shows that psychological factors such as perception/attitude on global environment or individual norms impact significantly to reduce private car use and accordingly the relevance of introducing MM approach instead of imposing regulations or expanding transport facilities.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.17 no.1
• /
• pp.107-120
• /
• 2022

The purpose of this study is to analyze the net effect and the combined effect of the determinants of the likelihood of start-up success of researchers at public research institutes. Based on the existing literature, the determinants of the researcher's likelihood of start-up success were reviewed, and a conceptual relationship between the determinants of the likelihood of start-up success was established. Data collection was conducted through a survey targeting researchers at public research institutes, and a total of 114 data were collected. The partial least squares (PLS) analysis method was used to analyze the net effect of the likelihood of start-up success determinant, and the fuzzy-set qualitative comparative analysis (fsQCA) was used to analyze the combined effect of the likelihood of start-up success determinant. In the PLS analysis results, it was found that technology commercialization probability and creative self-efficacy had a significant positive effect independently on the likelihood of start-up success. In the fsQCA results, we found a combined effect of increasing the likelihood of start-up success when the technology commercialization probability, technology commercialization capability, and creative self-efficacy were high. These research results provide academic implications for understanding the determinants of the likelihood of start-up success of researchers in public research institutes.

• The Journal of Korean Association of Computer Education
• /
• v.16 no.4
• /
• pp.1-11
• /
• 2013

The purpose of this study is to investigate a structural relationship among elementary students' self-determinant learning motivation, teaching-presence and learning outcomes (learning satisfaction, persistence) in blended learning environment. Participants were 5th and 6th grade students who enrolled in a mathematics learning service. The results showed that self-determinant learning motivation had direct effect on teaching presence, learning satisfaction and learning persistence. Teaching Presence had an direct effect on learning satisfaction and learning satisfaction had an direct effect on learning persistence. Based on the results, proper strategies were recommended to facilitate self-determinant learning motivation and teaching presence before and during learning since they play critical roles for the success of elementary students learning outcomes in a blended learning environment.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.17 no.2
• /
• pp.131-140
• /
• 2004

It really needs fuzzy decision making of integrity assessment considering about both durability and load carrying capacity for maintenance and administration, such as repairing and reinforcing. This thesis shows efficient models about reinforced concrete structure using CART-ANFIS. It compares and analyzes decision trees parts of expert system, using the theory of fuzzy, and applying damage & diagnosis at reinforced concrete structure and decision trees of integrity assessment using established artificial neural. Decided the theory of reinforcement design for recovery of durability at damaged concrete ＆ the theory of reinforcement design for increasing load carrying capacity keep stability of damage and detection. It is more efficient maintenance and administration at reinforced concrete for using integrity assessment model of this study and can carry out predicting cost of life cycle.

• Journal of the Korea Convergence Society
• /
• v.9 no.2
• /
• pp.349-357
• /
• 2018

The purpose of this study was to identify the self-determination motivation on learning flow by college nursing students and the mediation effects of metacognition. A sample of 145 subjects were recruited from two university in G city. And data were collected from Nov 21 to Nov 30, 2016. Data were analyzed using with SPSS 22.0. The factors affecting the learning flow were self-determination motivation, planing and monitoring of metacognition, sex and explanatory power was 66.3%. All of the metacognition factors had a partial mediating effect in the relationship between self-determination motivation and learning flow. This study is to provide basic data to develop the nursing education method to improve learning flow in the field where self regulated learning is increasing.

• Journal of Convergence for Information Technology
• /
• v.12 no.5
• /
• pp.62-70
• /
• 2022

This study was attempted to understand the effect of university students' psychological well-being and interpersonal competence on their career decision-making self-efficacy. The participants of this study were 154 university students, and data collection was conducted from November 1 to December 10, 2019. The collected data were analyzed using x²-test, t-test, ANOVA, Pearson's correlation coefficients, and stepwise multiple regression. Psychological well-being and interpersonal competence were found to be significant influencing factors on career decision-making self-efficacy and the explanation power was 41.6% (F=66.48, p<.001). When establishing a program that can improve career decision-making self-efficacy of university student, psychological well-being and interpersonal competence, which are factors that affect career decision self-efficacy revealed through the results of this study, should be considered.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.14 no.6
• /
• pp.47-54
• /
• 2014

Based on the indiscernible relation of rough set, the inevitability of superposition and inconsistency of data makes the reduction of attributes very important in information system. Rough set has difficulty in the difference of attribute reduction between consistent and inconsistent information system. In this paper, we propose the new uncertainty measure and attribute reduction algorithm by Bayesian posterior probability for correlation analysis between condition and decision attributes. We compare the proposed method and the conditional information entropy to address the uncertainty of inconsistent information system. As the result, our method has more accuracy than conditional information entropy in dealing with uncertainty via mutual information of condition and decision attributes of information system.