• Journal of the Korea Concrete Institute
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• v.24 no.3
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• pp.275-283
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• 2012

Steel Plate for Rebar Connection was recently developed to splice rebars in delayed slab-wall joints in high-rise building, slurry wall-slab joints, temporary openings, etc. It consists of several couplers and a thin steel plate with shear key. Cyclic loading tests on slab-wall joints were conducted to verify structural behavior of the joints having Steel Plate for Rebar Connection. For comparison, joints with Rebend Connection and without splices were also tested. The joints with Steel Plate for Rebar Connection showed typical flexural behavior in the sequence of tension re-bar yielding, sufficient flexural deformation, crushing of compression concrete, and compression rebar buckling. However, the joints with Rebend Connection had more bond cracks in slabs faces and spalling in side cover-concrete, even though elastic behavior of the joints was similar to that of the joints with Steel Plate for Re-bar Connection. Consequently, the joints with Rebend Connection had less strengths and deformation capacities than the joints with Steel Plate for Re-bar Connection. In addition, stiffness of the joints with Rebend Connection degraded more rapidly than the other joints as cyclic loads were applied. This may be caused by low elastic modulus of re-straightened rebars and restraightening of kinked bar. For two types of diameters (13mm and 16mm) and two types of grades (SD300 and SD400) of rebars, the joints with Steel Plate for Rebar Connection had higher strength than nominal strength calculated from actual material properties. On the contrary, strengths of the joints with Rebend Connection decreased as bar diameter increased and as grade becames higher. Therefore, Rebend Connection should be used with caution in design and construction.

• Journal of The Korean Association For Science Education
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• v.31 no.6
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• pp.864-875
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• 2011

The purpose of this study was to investigate high school students' understanding of acid-base related concepts using three different titration technologies. The test population was composed of 209 students from three classes in the 10th grade. The different titration experiments using indicator, or pH-meter or MBL were performed in each class unit, respectively. The analyses of the effect on the understanding of different titration technologies were carried out by comparing the mean scores of the concept test taken before and after the titration for the three groups. The results of the acid-base related concept test indicated that statistically significant effects on the understanding of the concepts were shown by all groups. Comparing the effect on the comprehension of the three groups, the MBL group showed the most significant effect, while the pH-meter group showed the least significant. It was also attempted to analyze the effect on comprehension of the concepts by the cognitive and the motivational levels of students. This study revealed that the students in the formal operation stage showed higher understanding of the acidbase related concepts, while those in the concrete operation stage showed lower comprehension. It was also shown that the students at the active motivational level scored higher in comprehension than those who had a low score. The results of this study implied that each group showed differently enhanced comprehension of concepts by titration technologies. Therefore, teachers need to promote an appropriate experiment technology for the cognitive and motivational levels of students as well as try to help students express freely their own perspectives.

• Journal of Intelligence and Information Systems
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• v.22 no.4
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• pp.19-43
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• 2016

This study examines the causes of the Asian exchange rate crisis and compares it to the European Monetary System crisis. In 1997, emerging countries in Asia experienced financial crises. Previously in 1992, currencies in the European Monetary System had undergone the same experience. This was followed by Mexico in 1994. The objective of this paper lies in the generation of useful insights from these crises. This research presents a comparison of South Korea, United Kingdom and Mexico, and then compares three different models for prediction. Previous studies of economic crisis focused largely on the manual construction of causal models using linear techniques. However, the weakness of such models stems from the prevalence of nonlinear factors in reality. This paper uses a structural equation model to analyze the causes, followed by a neural network model to circumvent the linear model's weaknesses. The models are examined in the context of predicting exchange rates In this paper, data were quarterly ones, and Consumer Price Index, Gross Domestic Product, Interest Rate, Stock Index, Current Account, Foreign Reserves were independent variables for the prediction. However, time periods of each country's data are different. Lisrel is an emerging method and as such requires a fresh approach to financial crisis prediction model design, along with the flexibility to accommodate unexpected change. This paper indicates the neural network model has the greater prediction performance in Korea, Mexico, and United Kingdom. However, in Korea, the multiple regression shows the better performance. In Mexico, the multiple regression is almost indifferent to the Lisrel. Although Lisrel doesn't show the significant performance, the refined model is expected to show the better result. The structural model in this paper should contain the psychological factor and other invisible areas in the future work. The reason of the low hit ratio is that the alternative model in this paper uses only the financial market data. Thus, we cannot consider the other important part. Korea's hit ratio is lower than that of United Kingdom. So, there must be the other construct that affects the financial market. So does Mexico. However, the United Kingdom's financial market is more influenced and explained by the financial factors than Korea and Mexico.

• Journal of Intelligence and Information Systems
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• v.22 no.4
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• pp.69-85
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• 2016

Successful relationship with loving partners is one of the most important factors in life. In psychology, there have been some previous researches studying the factors influencing romantic relationships. However, most of these researches were performed based on statistical analysis; thus they have limitations in analyzing complex non-linear relationships or rules based reasoning. This research analyzes commitment and persistence in heterosexual involvement according to styles of loving using a datamining technique as well as statistical methods. In this research, we consider six different styles of loving - 'eros', 'ludus', 'stroge', 'pragma', 'mania' and 'agape' which influence romantic relationships between lovers, besides the factors suggested by the previous researches. These six types of love are defined by Lee (1977) as follows: 'eros' is romantic, passionate love; 'ludus' is a game-playing or uncommitted love; 'storge' is a slow developing, friendship-based love; 'pragma' is a pragmatic, practical, mutually beneficial relationship; 'mania' is an obsessive or possessive love and, lastly, 'agape' is a gentle, caring, giving type of love, brotherly love, not concerned with the self. In order to do this research, data from 105 heterosexual couples were collected. Using the data, a linear regression method was first performed to find out the important factors associated with a commitment to partners. The result shows that 'satisfaction', 'eros' and 'agape' are significant factors associated with the commitment level for both male and female. Interestingly, in male cases, 'agape' has a greater effect on commitment than 'eros'. On the other hand, in female cases, 'eros' is a more significant factor than 'agape' to commitment. In addition to that, 'investment' of the male is also crucial factor for male commitment. Next, decision tree analysis was performed to find out the characteristics of high commitment couples and low commitment couples. In order to build decision tree models in this experiment, 'decision tree' operator in the datamining tool, Rapid Miner was used. The experimental result shows that males having a high satisfaction level in relationship show a high commitment level. However, even though a male may not have a high satisfaction level, if he has made a lot of financial or mental investment in relationship, and his partner shows him a certain amount of 'agape', then he also shows a high commitment level to the female. In the case of female, a women having a high 'eros' and 'satisfaction' level shows a high commitment level. Otherwise, even though a female may not have a high satisfaction level, if her partner shows a certain amount of 'mania' then the female also shows a high commitment level. Finally, this research built a prediction model to establish whether the relationship will persist or break up using a decision tree. The result shows that the most important factor influencing to the break up is a 'narcissistic tendency' of the male. In addition to that, 'satisfaction', 'investment' and 'mania' of both male and female also affect a break up. Interestingly, while the 'mania' level of a male works positively to maintain the relationship, that of a female has a negative influence. The contribution of this research is adopting a new technique of analysis using a datamining method for psychology. In addition, the results of this research can provide useful advice to couples for building a harmonious relationship with each other. This research has several limitations. First, the experimental data was sampled based on oversampling technique to balance the size of each classes. Thus, it has a limitation of evaluating performances of the predictive models objectively. Second, the result data, whether the relationship persists of not, was collected relatively in short periods - 6 months after the initial data collection. Lastly, most of the respondents of the survey is in their 20's. In order to get more general results, we would like to extend this research to general populations.

• Korean Chemical Engineering Research
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• v.43 no.2
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• pp.206-214
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• 2005

Heterogeneously-catalyzed oxidation of aqueous phase trichloroethylene (TCE) over supported metal oxides has been conducted to establish an approach to eliminate ppm levels of organic compounds in water. A continuous flow reactor system was designed to effect predominant reaction parameters in determining catalytic activity of the catalysts for wet TCE decomposition as a model reaction. 5 wt.% $CoO_x/TiO_2$ catalyst exhibited a transient period in activity vs. on-stream time behavior, suggesting that the surface structure of the $CoO_x$ might be altered with on-stream hours; regardless, it is probable to be the most promising catalyst. Not only could the bare support be inactive for the wet decomposition reaction at $36^{\circ}C$, but no TCE removal also occurred by the process of adsorption on $TiO_2$ surface. The catalytic activity was independent of all particle sizes used, thereby representing no mass transfer limitation in intraparticle diffusion. Very low TCE conversion appeared for $TiO_2$-supported $NiO_x$ and $CrO_x$ catalysts. Wet oxidation performance of supported Cu and Fe catalysts, obtained through an incipient wetness and ion exchange technique, was dependent primarily on the kinds of the metal oxides, in addition to the acidic solid supports and the preparation routes. 5 wt.% $FeO_x/TiO_2$ catalyst gave no activity in the oxidation reaction at $36^{\circ}C$, while 1.2 wt.% Fe-MFI was active for the wet decomposition depending on time on-stream. The noticeable difference in activity of the both catalysts suggests that the Fe oxidation states involved to catalytic redox cycle during the course of reaction play a significant role in catalyzing the wet decomposition as well as in maintaining the time on-stream activity. Based on the results of different $CoO_x$ loadings and reaction temperatures for the decomposition reaction at $36^{\circ}C$ with $CoO_x/TiO_2$, the catalyst possessed an optimal $CoO_x$ amount at which higher reaction temperatures facilitated the catalytic TCE conversion. Small amounts of the active ingredient could be dissolved by acidic leaching but such a process gave no appreciable activity loss of the $CoO_x$ catalyst.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.3
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• pp.333-341
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• 2008

The objective of this study was to investigate the physical characteristics of sourdough starter containing red koji rice (SD1: 0%, SD2: 10%, SD3: 20% and SD4: 40%) and to compare the quality characteristics of sourdough breads containing 10% red koji rice powder with those of sourdough bread containing with vollsauer powder (VPB) and white wheat bread (WWB) prepared with starter SD1. The activity of ${\beta}$-amylase increased with increasing amount of red koji rice. Organic acids of sourdough starter with red koji rice (SD2, SD3 and SD4) were higher than that of sourdough starter SD1. The peak time, peak value width of tail, pH, and L value were high in WWB, while the proofing power and a and b values of WWB were lower than those of VPB and sourdough bread containing SD1 (SPB1), SD2 (SPB2), SD3 (SPB3), or SD4 (SPB4). The lowest pH, baking loss, and specific volume were observed with the VPB. The baking loss of SPB4 (sourdough bread containing SD4) was the highest (13.01%). Overall, hardness and springiness were low in sourdough bread containing red koji rice powder, whereas sourness and off-flavor were higher than in VPB. Results of specific volumes, hardness and sensory evaluation indicated that the addition of 10% red koji rice powder to sourdough starter can improve the quality characteristics of the sourdough bread.

• Management & Information Systems Review
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• v.36 no.3
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• pp.167-184
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• 2017

In this study, we investigated the effect of offline banking trust on smart banking trust. As influencing factors of smart banking trust, this study compared offline banking trust, smart banking's system quality, and information quality. For the empirical study, 186 questionnaire data were collected from smart banking users and the data were analyzed using Smart-PLS 2.0. As results, it was verified that there is trust transfer in FinTech service, by the significant effect of offline banking trust on smart banking trust. And it was proved that the effect of offline banking trust on smart banking trust is lower than that of smart banking itself. The contribution of this study can be seen in both academic and industrial aspects. First, it is the contribution of the academic aspect. Previous studies on banking were focused on either offline banking or smart banking. But this study, focus on the relationship between offline banking and online banking, proved that offline banking trust affects smart banking trust. Next, it is the industrial contribution. This study showed that offline banking characteristics of traditional commercial banks affect the trust of emerging smart banking service. This means that the emerging FinTech companies are not advantageous in the competition of trust building compared to traditional commercial banks. Unlike traditional commercial banks, the emerging FinTech is innovating the convenience of customers by arming them with new technologies such as mobile Internet, social network, cloud technology, and big data. However, these FinTech strengths alone can not guarantee sufficient trust needed for financial transactions, because banking customers do not change a habit or an inertia that they already have during using traditional banks. Therefore, emerging FinTech companies should strive to create destructive value that reflects the connection with various Internet services and the strength of online interaction such as social services, which have an advantage over customer contacts. And emerging FinTech companies should strive to build service trust, focused on young people with low resistance to new services.

• Journal of dental hygiene science
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• v.10 no.4
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• pp.241-250
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• 2010

The purpose of this study, which was processed from March $22^{nd}$ to April $9^{th}$ of 2010, was to figure out recognition, well-formed instructions, and Practical application about dental hygiene devices based on the dental health characteristics of 350 adults who dwell in Busan and Gyeongnam regions. Also, this study recommended the adults to use dental hygiene devices and provided such devices to help individuals take care of their dental health at home. The collected data was statistically processed with a statistics SPSS (Statistical Packages for Social Science 14.0. SPSS Inc. USA) program. First of all, in order to demonstrate the characteristics of the sample population statistics and that of the descriptive data, frequency analysis was performed and to find out the relationship between variations of the dental health, Chi-squared test through Crosstabs was operated. According to the study, recognition and Practical application of dental hygiene devices were very low. Therefore, public announcement about necessity and effectiveness of such devices should be reinforced nationwide and instructions on choosing the right device and using of the dental hygiene devices based on patients' conditions by dental hygienic human efforts gathered from dental health organization should be carried out.

• Korean journal of applied entomology
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• v.47 no.2
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• pp.163-168
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• 2008

Temperature dependent development of Tetranychus. urticae Koch was studied on the leaf of eggplant at 17, 22, 27, 32 and $37^{\circ}C$. T. urticae showed a minimum mortality at $27^{\circ}C$ and it increased at higher or lower temperatures than $27^{\circ}C$. The hatchability was low at 17 and $37^{\circ}C$. The duration of development decreased with increasing temperatures i.e., 5.3d at $37^{\circ}C$ and 25.8d at $17^{\circ}C$. Linear regression analysis of temperature vs. rate of development yielded the higher $r^2{\geq}0.88$ resulting in a good fit of the estimated line in the range of $17{\sim}37^{\circ}C$. Developmental zero temperature was $12.5^{\circ}C$ for the entire immature stage of female and $12.8^{\circ}C$ for that of male. Thermal constants were 80.5 and 74.7 degree days for those of female and male, respectively. Adult life span and oviposition period decreased with increasing temperatures. The number of eggs laid per female peaked at 141.0 eggs at $27^{\circ}C$, while that was a minimum 78.0 eggs at $37^{\circ}C$. Rate of hatchability, ratio of female, and $R_o$ were increased up to $27^{\circ}C$, and than declined thereafter. Intrinsic rate of natural increase (Rm) increased with rising temperatures and showed a maximum 0.5652 at $37^{\circ}C$. Also, ${\lambda}$ increased with increasing temperature. Doubling time (Dt) and generation time (T) decreased with increasing temperature.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.4
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• pp.1-14
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• 2017

New business management methods different from the past are necessary because of the rapid changes of the corporates' environment. KOSDAQ(Korean Securities Dealers Automated Quotation) companies should be expected the more affirmative business performance of companies by listing, but it is a well-known that they have problems of low business performance mostly. This paper aims to investigate the influential factors on enhancing corporate innovation and nonfinantial business performance, and to clarify practical measures and present a solution of KOSDAQ companies' problems through analysis of previous researches and an empirical research. This research present corporate entrepreneurship and human resources innovation as impact factors on the business performance to apply finely the path of technological innovation for the solution of the relevance investigation limit between the complexity of corporates' innovation paths and the firms' performance. And also knowledge management activities and external networks management or the firms have been adopted as a corporate innovation activities for free from quantitative measures, such as conventional research and development(R&D) activities by considering recent corporates' knowledge business operations. The results of the empirical analysis shows that significant impact factors on corporate innovation activities are the firms' propensities of competitive advantage initiative, risk taking and chief executive officer's innovation. These can be interpreted that the CEOs' innovation propensity should be enhanced for stimulating corporate's innovaton activities, which include the CEOs' interest in the development of new technology, the exploiting new businesses and their support of the innovation discipline for employees. In addition, it can be said that it is necessary to intensify more initiatives within those enterprise for enhancing the competitive advantage in the identical industry. The significant impact factors of corporate entrepreneurship and human resource innovation on the non-financial performance are resulted as the propensities of firms' competitive advantage initiative, CEOs' innovation and employees' innovaton. This shows that the higher propensities of firms' competitive advantage initiative, CEOs' innovation and employees' innovaton, the higher the cognitive degrees of business performance within each corporate, which include the members' awareness about firms' sales growth, market share growth, profit ratio growth, customers' preference and corporates' awareness.