• Bulletin of the Korean Chemical Society
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• v.6 no.5
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• pp.277-279
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• 1985

Orbital interactions of the types, ${\sigma}-{\pi},\;{\sigma}^*-{\pi},\;{\sigma}-{\pi}^*\;and\;{\sigma}^*-{\pi}^*$ are investigated for the rotamers of ${\alpha}$-X-acetones (X = F and Cl) using STO-3G method of calculation. It was found that the interactions are possible only in gauche forms, and the ${\sigma}^*-{\pi}^*$ interactions are in general greater than the $\sigma-\pi$ interactions due to the greater overlap, in spite of the greater energy gap involved; the greater ${\sigma}^*-{\pi}^*$ interaction causes greater lowering of ${\pi}^*$ level relative to the lowering of ${\sigma}$ in the ${\sigma}-{\pi}$ interaction so that both ${\sigma}-{\pi}^*$ and $n-{\pi}^*$ interactions are enhanced in the gauche forms. The extra stability of the gauche form and the red shift in the $n-{\pi}^*$ transition are thus found to be natural corollaries of the greater ${\sigma}^*-{\pi}^*$ interaction in the gauche forms.

• Bulletin of the Korean Chemical Society
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• v.13 no.2
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• pp.173-176
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• 1992

The spectroscopic studies of the 5,7-dimethoxycoumarin(5,7-DMC) and 4,5',8-trimethylpsoralen(TMP) and the conformational stability of 5,7-DMC-thymidine, 4,5',8-TMP-thymine were carried out by the CNDO/S and molecular mechanics calculation. Theoretical transition energies and direction of polarizations calculated by the CNDO/S method have been used for the interpretation of the observed results. The calculated absorption spectra of 5,7-DMC are qualitatively similar to experimental ones with their characteristic visible bands. MM2 force field calculation on the possible $C_4-cyclophotoadducts$ formed between 5,7-DMC and thymidine through a cycloaddition. of $C_3$, $C_4$ bond of 5,6-DMC to $C_5$, $C_6$ bond of thymidine showed the most stable photocycloadduct to have the anti-head to tail configuration. The major photoadduct of 4,5',8-TMP-thymine has the cis-anti configuration.

• Iberoamérica
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• v.22 no.2
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• pp.123-151
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• 2020

This paper shows a theoretical-reflective analysis on the importance of vocational training and value education to transition into models that are inclusive in cultural diversity, typical of the globalized and hyperconnected environment of modern societies. Interculturality is contextualized as a key element in linking teaching-learning processes with the uniqueness and problems associated with cultural ethnocentrism and alterity. In this sense, the work is part of a thematic review that contributes to the understanding, inclusion and recognition of cultural, racial and ethnic diversity in the different formal spaces of learning. As summary, value education and transversality are the basis for building educational interculturality in future generations.

• The Mathematical Education
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• v.29 no.1
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• pp.55-61
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• 1990

There are three objectives of this paper. First, we present an elegant and simple generalization of Abel's theorem (i .e. tile Abel summability (on the unit disk of the euclidean plane) is regular). Second, we consider the definition of Abel summability through lim (equation omitted) which immediately has clear connexctions with CeSARO summability and Cesaro sums (equation omitted). This approach examplifies some simple aspects of so-called Tauberian theorems of divergent series. Third, we present the applications of the previous results to find the limits of transition probabilities of homogeneous Marker chain. Finally, we explain why the original Abel's theorem which looks obvious is difficult to be proved, and can not be proved analytically.

• International Journal of Computer Science & Network Security
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• v.24 no.5
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• pp.89-94
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• 2024

The main purpose of the study is to determine the main elements of the use of digital technologies for learning a foreign language in educational institutions. The era of digital technologies is a transition from the traditional format of working with information to a digital format. This is the era of the total domination of digital technologies. Digital technologies have gained an unprecedented rapid and general distribution. In recent years, all spheres of human life have already undergone the intervention of digital technologies. Therefore, it is precisely the educational industry that faces a difficult task - to move to a new level of education, where digital technologies will be actively used, allowing you to conveniently and quickly work in the information field for more effective learning and development. The study has limitations and they relate to the fact that the practical activities of the process of using digital technologies in the system of preparing the study of a foreign language were not taken into account.

• Korean Journal of Social Welfare
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• v.66 no.3
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• pp.185-208
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• 2014

This study is to identify the factors deterring or precipitating the exit from welfare recipiency to labor market in the Korean social assistance program. The results from the empirical analyses of the Korea Welfare Panel Study(KOWEPS) show that the duration dependency is not due to increasing welfare dependency with duration, but to the fact that longer stayers have many vulnerable conditions to escape from poverty. Particularly, the main factors determining the transition from recipiency to labor market are not individual or household characteristics such as human or social capital. Those having adolescents of secondary education in their households or participating in some effective labor market program such as job placement service tend to have significant effects on the exit rates from recipiency. That means that the institution-related factors such as the education and health supports combined with benefits and the effective labor market programs are important in the translation from recipiency to labor market of working-age recipients in the Korean social assistance scheme.

• Journal of Welding and Joining
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• v.28 no.5
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• pp.69-74
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• 2010

Irradiation behavior of the reactor pressure vessel SA508 class 3 steel weld metals was examined by Charpy V Notch impact specimens. The specimens were exposed to a fluence of $2.8{\times}1019$ neutrons(n)/$cm^2$(E>1 MeV) at $288^{\circ}C$. The irradiation damage of weld metal was evaluated by comparison between unirradiated and irradiated specimens in terms of absorbed energy and lateral expansion. The specimens for neutron irradiation were welded by submerged arc welding process at a heat input of 3.2 kJ/mm which showed good toughness in terms of weld microstructure, absorbed energy and lateral expansion. The post-irradiation Charpy V notch 41J and 68J transition temperature elevation were $65^{\circ}C$ and $70^{\circ}C$, respectively. This elevation was accompanied by a 20% reduction in Charpy V notch upper shelf energy level. The lateral expansion at 0.9mm irradiated Charpy specimens showed temperature elevation of $65^{\circ}C$ and was greatly decreased due to radiation damage.

• Journal of Educational Research in Mathematics
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• v.17 no.2
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• pp.91-109
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• 2007

This study deals with the problem of transition from arithmetic to algebra and the relationship between elementary and secondary school mathematics for systems of linear equations. In elementary school, activity for solving word problems related to systems of linear equations in two variables falls broadly into using two strategies: Guess and check and making a table. In secondary school, those problems are solved algebraically, for example, by solving systems of equations using the technique of elimination. The analysis of mathematics textbooks shows that there is no link between strategies of elementary school mathematics and secondary school mathematics. We devised an alternative way to reinforce link between elementary and secondary school mathematics for systems of linear equations. Drawing a diagram can be introduced as a strategy solving word problems related to systems of linear equations in two variables in elementary school. Moreover it is closely related to the idea of the technique of elimination of secondary school mathematics. It may be a critical juncture of elementary-secondary school mathematics in the case of systems of linear equations in two variables.

• Korean Journal of Health Education and Promotion
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• v.11 no.1
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• pp.70-84
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• 1994

On the basis of the study intended to research by cross-sectional study keeped pace with semi-longitudinal study the growth accelerating phenomena that MGA(Maximum Growth Age) in teenager's body height. The duration of study is from Oct. 1st. 1991 to September 30 1992 and the data are analysed through computer. The body height and MGA of Koreans who had been for during the period from 1898 to 1973 proved transition of the growth accelerating phenomena by research data reported between 1913 and 1990. The results are as follows: 1. Maximum Growth Age The MGA's in body height of male are respectively the age 15.024 in 1913, 14.28 in 1940, 13.65 in 1959, 13.86 in 1967, 12.52 in 1983, 11.39 in 1987, 12.36 in 1990, while those of female are the age of 12.0 in 1940, 12.36 in 1959, 10.45 in 1969, 11.15 in 1985, 10.27 in 1988, 10.23 in 1990 ; these data show that the MGA of the Korean has been getting younger. 2. The correlation of the MGA's in body height are as below ; Male ; r = -0.448(p<0.01) Female ; r = -0.404(p<0.05) 3. The equation of linear regression of MGA's in body height are as below ; Male ; Y(MGA) = -0.0316X(the year)+75.297 Female ; Y(MGA) = -0.035X(the year)+79.986 4. The MGA's in body height are shown in Table 3. 5. From the transition of the growth accelerating phenomena, we can compute the fact that the MGA's has been getting younger by 0.3 year per 10 years. 6. The future growth accelerating phenomena in body height, the MGA's of male are respectively the age 12.25 in 1995, 12.09 in 2000, 11.94 in 2005, 11.78 in 2010, while those of female are the age of 10.16 in 1995, 9.98 in 2000, 9.81 in 2005, 9.64 in 2010, these data show that the MGA of female are more younger than that of male.

• Journal of Digital Convergence
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• v.12 no.11
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• pp.565-574
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• 2014

The authors examined the life of university students in Korea. Overall, the life illustrated by Korean university students was grouped into four themes as follows: 'never experienced critical thinking, don't have enough time to critically think,' 'looking for decisions and conclusions by someone else,' 'just doing my job although I don't want,' and 'I don't know what I am supposed to do for my own life.' Since participants of this current study spent their adolescence under the standardized education as well as the regulated direction, they did not experienced their proper independent life. Given the fact that Korean university students had troubled with their life transition into adulthood, more efforts are needed to change the social perceptions toward university students and to develop the appropriate action derived by colleges/universities in order to guide university students' healthy transition into adulthood.