• Communications of the Korean Mathematical Society
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• v.20 no.1
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• pp.23-34
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• 2005

Let R be a ring with left identity. Let G : $R{\times}R{\to}R$ be a symmetric biadditive mapping and g the trace of G. Let ${\alpha}\;:\;R{\to}R$ be an endomorphism and ${\beta}\;:\;R{\to}R$ an epimorphism. In this paper we show the following: (i) Let R be 2-torsion-free. If g is (${\alpha},{\beta}$)-skew-commuting on R, then we have G = 0. (ii) If g is (${\beta},{\beta}$)-skew-centralizing on R, then g is (${\beta},{\beta}$)-commuting on R. (iii) Let $n{\ge}2$. Let R be (n+1)!-torsion-free. If g is n-(${\alpha},{\beta}$)-skew-commuting on R, then we have G = 0. (iv) Let R be 6-torsion-free. If g is 2-(${\alpha},{\beta}$)-commuting on R, then g is (${\alpha},{\beta}$)-commuting on R.

• Journal of the Korean Institute of Intelligent Systems
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• v.21 no.2
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• pp.250-253
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• 2011

In this paper, we study characterizations of fuzzy weakly r-M continuous function on r-minimal structures in terms of generalized fuzzy r-minimal open sets.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.11 no.2
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• pp.103-107
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• 2011

The concepts of fuzzy r-minimal semicompact, almost fuzzy r-minimal semicompact, and nearly fuzzy r-minimal semicompact on fuzzy r-minimal spaces arc introduced. We also investigate the relationships between fuzzy r-M-semicontinuous mappings and several types of fuzzy r-minimal semicompactness.

• International journal of advanced smart convergence
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• v.9 no.2
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• pp.28-37
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• 2020

We conducted a comprehensive review on the previous research on r-Learning. By reviewing 843 previous studies about r-Learning published from 2004 to 2015, this study investigated 1) the trend of research on r-Learning over time, 2) the characteristics of targeted students in r-Learning, 3) the educational activities implemented for r-Learning, and 4) the types of educational robots used for r-Learning. The study found that the research on r-Learning has rapidly and steadily increased and the types of educational activities and educational robots has been diversified. Relying on the findings of this review, this study suggests 1) ensuring growth in both the quality and the quantity of research on r-Learning, 2) broadening the target student population of r-Learning beyond the age-limited boundaries, 3) enhancing educational activities of r-Learning, and 4) recognizing the necessity for systematic and clear concepts of types of educational robots.

• Journal of Biomedical Engineering Research
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• v.22 no.2
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• pp.197-204
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• 2001

• International Journal of Internet, Broadcasting and Communication
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• v.13 no.1
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• pp.11-19
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• 2021

The purpose of this study is to check whether the satisfaction of the R&D (Research & Development) project directly affects the R&D performance, and to find out whether the satisfaction with regional connectivity and the satisfaction with the R&D operation management significantly mediate the relationship that the satisfaction with the R&D project has on the R&D performance. In order to verify the research hypothesis on this, a total of 51 companies located in Jeollanam-do that actually conducted R&D research projects were surveyed and analyzed. In order to conduct an empirical study based on the collected questionnaire, a survey questionnaire related to the variables of the study model was composed based on a sample of 51 questionnaires. We used the SPSS program to verify the hypotheses in this study, and the hypotheses were verified by analyzing the validity, reliability, correlation, and deflection. As a result, there was a positive (+) significant relationship between R&D project satisfaction and R&D performance. In addition, it was found that the relationship between R&D project satisfaction and R&D performance was significantly mediated by the satisfaction with R&D regional connectivity and satisfaction with R&D project operation management.

• Journal of applied mathematics & informatics
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• v.29 no.3_4
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• pp.1059-1066
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• 2011

We introduce the concept of fuzzy S-weakly r-M-continuous functions on fuzzy r-minimal spaces, and investigate some characterizations of such functions and the relations between the continuity and fuzzy r-minimal compactness on fuzzy r-minimal spaces.

• Economic and Environmental Geology
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• v.45 no.5
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• pp.579-587
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• 2012

The purpose of this study is to emphasize the necessity of extention of a government R&D planning scope. Presently, government R&D planning is focused on the selecting a R&D project. There is no R&D strategy for R&D conducting such as the composition of R&D team, collaboration and knowledge flow. Ordinarily these strategies are established by research director. This study analyzed the determinants of excellent R&D performance and proposed R&D strategy for R&D conducting using the patent bibliograpy information in energy resources production technology field. On the other hand, this study introduced the concept of technology lifecycle and showed that R&D strategy should be differentiated by technology lifecycle.

• Journal of Korea Technology Innovation Society
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• v.12 no.2
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• pp.360-387
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• 2009

In this paper, we analyse empirically the effects of internal financing on investment of innovative small and medium sized enterprises listed on Kosdaq Market of Korea Exchange. The main results of this study can be summarized as follows. Free cash flows by proxy variables of internal financing have the significant effects on R&D investment as well as fixed asset investment. Internal financing has much more effects on R&D investment of general enterprises listed on Kosdaq Market than that of venture enterprises listed on Kosdaq Market, and on R&D investment of innovative enterprises than that of non-innovative enterprises. Internal financing has more effects on asset-counted R&D investment than cost-counted R&D investment. Asset-counted R&D investment is counted in intangible assets on Balance Sheet, and cost-counted R&D investment is counted in cost on Income Statement. Internal financing has more effects on R&D investment of financial constrained enterprises than that of financial unconstrained enterprises. Financial constraints is measured by credit ratings. Faulkender and Smith (2007) emphasize that low credit ratings enterprises are more likely to face financial constraints, and they rely largely on internal financing.

• Journal of Korea Technology Innovation Society
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• v.10 no.4
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• pp.706-726
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• 2007

This study attempts to empirically investigate the effects of government R&D subsidies on private firm's R&D investment in Korean industry. The R&D subsidy effect is defined as the average percentage change in firm's R&D expenditures between what was actually observed among firms that received a subsidy and what these firms would have spent had the subsidy not been received. To measure the effect we use Difference-in-Differences (DID) model which sign as to whether the relationship between government subsidies and private R&D investments is on stimulating or displacing private R&D expenditures. The differences between this study and previous studies are that we tries to measure the effect of Government R&D across various sited firm groups such as large, small & medium, and venture firms and we add one lag of the subsidy indicator in order to capture the effect of the subsidies on private R&D during 2 consecutive period. Empirically, a firm with government R&D subsidy increases its own R&D investment by 13.9%. Also on average, 1% of government R&D subsidy leads to 0.031% of private R&D increase. The main results of this study are as follows : First, Government R&D subsidies stimulate private firm's R&D expenditures. Second, Government R&D subsidies greatly increase (statistically significant) company financed R&D expenditures only for large firms but had no effect on the R&D expenditures of small & medium sized firms and venture firms.