• Journal of Magnetics
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• v.11 no.2
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• pp.77-82
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• 2006

The structure and magnetic properties of Fe-Ni films, deposited by DC magnetron sputtering on Si(111) wafer, have been studied. The spin wave stiffness constant is determined by Brillouin light scattering (BLS) and compared with the value obtained from magnetization measurements. The range of exchange interaction was determined as 0.4 atomic distances in the film deposited in a bias magnetic field, which is 1/2 that in the film grown in no bias magnetic field. The results show that the dimensions of exchange coupling increased by the sputtering in the magnetic field.

• Journal of Magnetics
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• v.1 no.2
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• pp.69-74
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• 1996

Justeresos loops of melt-spun Nd13Fe77B10 cooled down at remanent state were measured at 4.2 K and 250 K. The hysteresis loops were analysed on the basis of the Stoner-Wohlfarth (S-W) model, the inter-grain exchange coupled single domain (SD) model and micromagnetism. The coercivity higher than that predicted from the S-W model and the striking shift of the thin minor loop along the H-axix observed at the fields of Hmax=4MA/m at 4.2 K indicated new evidences for the inter-grain exchange interaction . The S-W model failed in explaining the high iHc and the shift of the thin minor loop. The exchange coupled SD model was found to explain the experimental results qualitatively without difficulties associated with the S-W model. The micromagnetic calculations using a finite element technique simulated the experimental results fairly well quntitatively.

• Journal of the Korean Magnetics Society
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• v.7 no.1
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• pp.55-67
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• 1997

Double exchange interaction leads to the ferromagnetism by the direct coupling between conduction electrons and magnetic ions. The most intriguing feature of double exchange is the explicit connection of the conductivity with the magnetism, which has drawn much interest in relation to the colossal magnetoresistance (CMR) recently observed in manganese oxide compounds. In this review, we explain the basic physics of double exchange and examine the classical discussions.

• Proceedings of the Korean Magnestics Society Conference
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• 1994.10a
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• pp.9-9
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• 1994

• Educational Technology International
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• v.12 no.2
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• pp.95-116
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• 2011

This study examines effects of Facebook on language learning in terms of facilitating interaction and collaboration by applying Facebook in a Korean language class. Forty one exchange students from seventeen countries who participated in the study used Facebook to exchange information and complete group projects. Results show that Facebook was effective in sharing class materials, engaging in class community and collaborating to complete assignments. Students also comment that socializing with peers was helpful, yet more activities and discussion to draw active participation is needed. This study also points out the important role of instructors who implement social media and manage the class.

• Journal of the Korean Magnetics Society
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• v.11 no.5
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• pp.232-238
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• 2001

Experimentally it is well known that the magnetic properties significantly deteriorate when nanocomposite bonded magnet are made from nanocomposite ribbon. A decrease in maximum energy product of F $e_3$B+N $d_2$F $e_{14}$B nanocomposite from 14 MGOe in nanocomposite ribbon to 6.5 MGOe in powder compact was fecund to be general. Thus, the present study is focused on finding out the root of exchange decoupling of N $d_4$F $e_{73.5}$ $Co_3$H $f_{0.5}$G $a_{0.5}$ $B_{18.5}$ nanocomposite powder compacts. The exchange decoupling behavior of the powder compact of F $e_3$B+N $d_2$F $e_{14}$B composition was studied by measuring DC demagnetization and isothermal remanent demagnetization curves, which are essential for plotting produced $\delta$M curve. From the $\delta$M plot the deterioration in the magnetic properties resulted from the fact that the magnetostatic interaction became dominant rather thanthe exchange interaction in powder compact. It is concluded that the demagnetization behavior governed by the dominant magnetostatic interaction reduced the remanence magnetization, which caused the reduction of maximum energy Product of the powder compact. We also found that the elimination of residual stress which is unavoidably accumulated during grinding process enhanced the magnetic properties considerably.bly.bly.

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2338-2340
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• 2012

The spin exchange parameters of $VOSb_2O_4$ were evaluated by performing energy-mapping analysis based on density functional calculations. The spin exchange interaction between the nearest-neighbor $V^{4+}$ ions is strongly antiferromagnetic while other interactions are negligible. Thus, the magnetic structure of $VOSb_2O_4$ is best described by a spin-1/2 Heisenberg antiferromagnetic chain with no spin frustration.

• The Journal of Economics, Marketing and Management
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• v.12 no.1
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• pp.39-51
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• 2024

Purpose: This study aims to derive planning directions of community facilities integrating generations based on local communities to promote sustainable intergenerational exchange by analyzing the spatial configuration and programs of domestic and foreign generation-integrated community facilities based on local communities. Research design, data and methodology: Through theoretical consideration, the concept of intergenerational integration, types of intergenerational exchange, and spatial arrangement types were identified. Then, case study analysis of domestic and foreign community facilities with well-planned intergenerational exchange spaces and programs were conducted to identify intergenerational integration, and to derive community facility planning direction. Results: The results of this research are as follows. First, in terms of humanware, in order to revitalize continuous exchange between the 1st, 2nd, and 3rd generations, a systematic support system is needed to build mutual trust through voluntary participation by each generation. Second, it is important to provide a variety of shared spaces while maintaining the uniqueness of each facility from a hardware perspective, and must be planned in such a way that selective interaction takes place with privacy and interaction in mind. Third, in terms of software, programs that meet the characteristics of each user must be provided. Conclusions: It is expected that the results of this research can be used as basic data for planning community facilities that integrate generations based on local communities, contributing to the search for sustainable ways to revitalize intergenerational exchange in the future.

• Korean Institute of Interior Design Journal
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• v.19 no.1
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• pp.208-216
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• 2010

The design hotel where new life styles of users were created and the exchange of one's identity and the culture was executed was employed the interaction design which considered the attendance and experience of users as the important motives. This study is to discuss on the relationship between the design hotel and interaction design, and to compare and analyze the differences in the expression methods of them. It was concluded that the design hotel had a close relation with the properties of information supply, amusements, narrative, personalization, and social exchange in the interaction design, and it mainly used the digital media of non-material, the juxtaposition of strangeness, the change of structure, substitution of values, appropriation of hybrid as a means of its expression. In addition, it was revealed that the properties above did not simply apply to an open space but were connected as a dominant-subordinate relationship into one subject. It is expected that the field of interaction design in the design hotel will be expanded due to the spread of digital technology and its role and importance will be increased. Therefore, it is thought that the study to provide the development of a variety of contents of design hotel should be kept through the study of organic relation between different subjects, avoiding the indiscriminate use of the contents.

• Journal of the Korean Magnetics Society
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• v.1 no.2
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• pp.55-59
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• 1991

The temperature-dependent magnetization curves of amorphous Fe-Co-(Nd, Sm, Gd, Tb)-B alloys were measured using a vibrating sample magnetometer from 77 K up to 900 K. The spin wave stiffness constants and the range of the exchange interaction were calculated from the saturation magnetization values at 0 K. Curie temperatures and the Bloch coefficients estimated from the saturation magnetization curves. The low temperature dependence of magnetization is in good agreement with Bloch relation, $M_{s}(T)=M_{s}(O)(1-BT^{3/2}-CT^{5/2})$. The spin wave stiffness constant and the range of exchange interaction are decreased by substitution of heavy rare earth (Tb, Gd).