• Journal of Powder Materials
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• v.22 no.5
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• pp.344-349
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• 2015

$MgB_2$ bulk superconductors are synthesized by the solid state reaction of ($MgB_4$+xMg) precursors with excessive Mg compositions (x=1.0, 1.4, 2.0 and 2.4). The $MgB_4$ precursors are synthesized using (Mg+B) powders. The secondary phases ($MgB_4$ and MgO) present in the synthesized $MgB_4$ are removed by $HNO_3$ leaching. It is found that the formation reaction of $MgB_2$ is accelerated when Mg excessive compositions are used. The magnetization curves of $Mg_1+_xB_2$ samples show that the transition from the normal state to the superconducting state of the Mg excessive samples with x=0.5 and x=0.7 are sharper than that of $MgB_2$. The highest $J_c-B$ curve at 5 K and 20 K is achieved for x=0.5. Further addition of Mg decreases the $J_c$ owing to the formation of more pores in the $MgB_2$ matrix and smaller volume fraction of $MgB_2$.

• The Journal of the Korea Contents Association
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• v.16 no.5
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• pp.651-659
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• 2016

The purposes of this study is to investigate the influence of career recognition upon career development competencies and educational needs. To achieve this, the survey was carried out and 362 undergraduates participated. The findings of the survey were shown as follows: First, the students perceived that career management was needed the most, and then came career information searches. Next, career transition technologies, positive self-concept formation, career planning, and effective interpersonal relationships were in order. Second, the influence of career recognition upon the level of the preparations showed statistically significant differences, however, the influence of career recognition upon the level of the requirement did not reveal statistically significant differences. Third, the rating of the educational needs was identical from the first place to the third, but different from the fourth to the sixth. These results will contribute to enhancing the efficiency of career education.

• Animal cells and systems
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• v.11 no.2
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• pp.129-134
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• 2007

The initiation of eukaryotic DNA replication requires assembly of the pre-replicative complex (Pre-RC) through the concerted action of Orc, Cdc6, Cdt1 and Mcm2-7 complex during G1 phase. The pre-RC assembly licenses individual replication origins for the initiation of DNA replication and sufficient number of the pre-RC is essential for proper progression of S phase. However, it is not well known how cells recognize the completion of the pre-RC assembly before G1-S transition. In order to understand the cellular responses to the defects in pre-RC assembly, we depleted the known components of pre-RC proteins using the small interference RNAs in HeLa cells. Although the defects of pre-RC assembly by the depletion of the pre-RC proteins such as Orc2, Cdt1, Mcm2 & Mcm10 did not elicit the activation of Chk1- or Chk2-dependent checkpoint pathways, these cells still showed significant decrease in the cellular level of Cdc25A proteins. These results suggests that a novel checkpoint pathway exist in HeLa cells, which is not dependent upon Chk1 or Chk2 proteins and play essential roles in the cellular responses to the defects in the pre-RC assembly. Also, among those four proteins tested in this study, the depletion of Mcm10 and Cdt1 proteins significantly increased the apoptotic cell death in HeLa cells, suggesting that these proteins not only play roles in the pre-RC assembly, but also are involved in the checkpoint responses to the defects in the pre-RC assembly.

• Journal of Families and Better Life
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• v.35 no.1
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• pp.139-158
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• 2017

Following the global trend of the delayed transition to adulthood, the number of unmarried middle aged adult children living with, or economically dependent on their parents has increased in Korea. Middle aged adult children in Korea are traditionally expected to satisfy their duty to support their elderly parents both in economic and emotional needs. This study aims to explore group differences in unmarried adult children in their mid 30s or older and in parents having unmarried middle aged child(ren) depending on co-residency and the children's eonomic dependency in Korea. Using quota sampling in terms of living arrangements (living together vs. living apart), 500 unmarried adult children 35 years of age or older and 500 elderly parents, having at least one unmarried child in the mid of 30s or over, were selected in Seoul, Korea in June 2016. First, the findings show that unmarried adult children living together with their parents and depending on their parents economically were in the lowest level of educational achievement and the lowest level of monthly average income among the respondents. Second, both unmarried adult children and parents from the group of co-residency and economically dependent showed the lowest level of psychological well-being. Third, parents from the group of co-residency and economically independent had mostly positive relationships with children, whereas, parents from the group of living apart and economically dependent reported the most negative relationships. Finally, respondents included in the group of co-residency had positive attitudes toward marriage and the support for their elderly parents regardless of the child's economic dependency. This study has implications for the increasing number of unmarried middle aged adult children and their elderly parents.

• Journal of the Korean earth science society
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• v.28 no.4
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• pp.462-477
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• 2007

The purpose of this study is to determine the petrology of basalt and the volcanic process in the Seondol cinder cone, Seobjikoji area, eastern Jeju Island. The Seondol cinder cone is mainly composed of spatters in the lower part, pyroclastic deposits including reddish brown blocks, ashes with volcanic bombs in the middle part, and dark black scoria deposits in the upper part. The volcanic sequences suggest volcanic processes that progress through Strombolian eruption and end with Hawaiian lava effusion which breached the cinder cone northwestward and extended over northwestward as lava delta and basalt emplaced as a volcanic neck in the central part of crater in the cinder cone. The age of basalt lava flows is about $95\;{\pm}\;3\;ka$. The basalts belong to transitional basalt and show products of fractional crystallization of clinopyroxene and olivine from a parental basalt magma on the basis of variation diagram of major, trace and rare earth elements. Basalts in the region of this study are plotted at the region of within plate basalt.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.5
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• pp.67-75
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• 2016

The financial difficulties which North Korean refugees encounter during the process of transition into South Korean society is due to their low income and insufficient expertise. Hence this research was conducted for the purpose of improving the policy and system to support North Korean refugees' starting of businesses. As a result, the self-efficacy, which is one of the individual characteristics, influences the motivation for starting business. In addition, it has been revealed that the motives and education on starting business also influence the motivation for starting business. By observing regulation effect of social adaptation, it has been found out that the interaction between the personal characteristics such as risk-taking attribute and the previous experience of starting business, along with interaction effect on social adaptation and motives and social adaptation, is statically influencing as well. On the basis of results, to efficiently support North Korean refugees' starting business, it is necessary to conduct education on starting business to boost their self-efficacy and the support must be executed based on their levels of motives, risk-taking attribute and social adaptation.

• Journal of Preventive Medicine and Public Health
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• v.39 no.6
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• pp.469-476
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• 2006

Objectives : To investigate the effect of parents' social class on infant and child mortality rates among the birth cohort, for the period of transition to and from the Koran economic crisis 1995-2004. Methods : All births reported to between 1995 and 2004 (n=5,711,337) were analyzed using a Cox regression model, to study the role of the social determinants of parents in infant and child mortality. The results were adjusted for the parents' age, education and occupation, together with mother's obstetrical history. Results. The crude death rate among those under 10 was 3.71 per 1000 births (21,217 deaths among 5,711,337 births) between 1995 and 2004. The birth cohorts from lower educated parents less than elementary school showed higher mortality rates compared with those from higher educated parents over university level (HR:3.0 (95%CI:2.8-3.7) for father and HR:3.4 (95%CI:3.3-4.5) for mother). The mother's education level showed a stronger relationship with mortality among the birth cohort than that of the fathers. The gaps in infant mortality rates by parents' social class, and educational level became wider from 1995 to 2004. In particular, the breadth of the existing gap between higher and lower parents' social class groups has dramatically widened since the economic crisis of 1998. Discussions : This study shows that social differences exist in infant and child mortality rates. Also, the gap for the infant mortality due to social class has become wider since the economic crisis of 1998.

• Elastomers and Composites
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• v.47 no.1
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• pp.75-81
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• 2012

Acrylic rubber was synthesized using ethyl acrylate. butyl acrylate, methoxyethyl acrylate as main monomers and glycidyl methacrylate as cure site monomer by emulsion polymerization. Rubber compound was made by adding 2,2-bis[4-(4-aminophenoxy)phenyl]propane as crosslinking agent. Increase of ethyl acrylate content in the main monomer ratio resulted in enhancement of heat resistance due to decrease of glass transition temperature in acrylic rubber. And also oil resistance was increased with increasing content of ethyl acrylate because ethyl acrylate has the highest ester concentration in the three main monomers. With content of 2,2-bis[4-(4-aminophenoxy)phenyl]propane, both tensile strength and elongation were increased until 2 phr, but in higher content than that, they decreased owing to reduction of viscosity and elongation by increase of crosslinking density.

• School Mathematics
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• v.8 no.2
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• pp.139-160
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• 2006

It seems that North Korea has been trying to reorganize its educational system as well as its economic system on a large scale since July 1, 2002. There has been a decrease in quantity of math textbooks by about 30% decrease. Until the 1990's, geometry and algebra had been kept apart from each other in North Korea, but they are put together now. Moreover many changes have been made in both contents and methods of teaching. For example, an area model is used in North Korea to teach operation of fraction, which makes the learning period shorter. This idea will provide us with many implication when we need to ready for decreasing the quantities in the future. Moreover teaching methods of division algorithms need to be reconsidered since the visual algorithm of division could help save the thinking in problem solving.

• Journal of the Korean Society of Radiology
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• v.9 no.7
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• pp.495-500
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• 2015

Health care privatization will have a very significant impact on the quality of medical service and income redistribution and risk diversification. This study was conducted to improve the situation without too much insistence that one did not understand the essence rife about the privatization of health care. In this study, grasp the implications of the current health care debate to be privatized, and dealing with the claims accordingly. Seeks to help establish an objective perspective, looking at the pros and cons at the same time claims for medical privatization policy. The Health and diversification through the capitalist market access as part of the transition process is being overlooked as a new growth engine industries. But health care is constrained to follow the growth of universal access and how to deal with life because it is practical conduct of the person. In addition to services that are not only for the benefit of the profit or government institutions.