• Journal of the Korean Society for Heat Treatment
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• v.18 no.1
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• pp.29-40
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• 2005

Formation of nanocrystalline ferrite was investigated using milled powders obtained by planetary ball milling of chips, which were made by high speed mechanical cutting of a low carbon steel(0.15%C-1.1%Mn-0.01%Ti). After 4 hour milling the chips were changed to powders of $50{\mu}m$ in average size, and with increasing milling time the powders were refined to about $3{\mu}m$ for 128 hour and showed more equiaxed shapes. Nanocrystalline(nc) region appeared in the surfaces of powders milled for 1 hour, and the 4 hour milled powders were almost filled with nc region. Hardness of nc region was much higher than that of work-hardened(WH) region. With increasing milling time, ferrite and cementite in pearlite were severely deformed and lamellar spacing was decreased, and then cementites began to disappear after 4 hour milling due to dissolution into ferrite. Deformation bands formed in lightly work-hardened region showed large width and similar crystallographic orientations. Spacing of deformation bands was decreased with deformation and the layered microstructure consisting of narrow deformation bands subdivided into variously oriented small grains was formed by more deformation, and eventually this structure seemed to be evolved to the nc structure by further deformation. It is also conjectured the growth of nc ferrite grains occurred through the coalescence of nanocrystalline ferrites rather than the nucleation and growth of recrystallized grains.

• Journal of Science and Technology Studies
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• v.8 no.2
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• pp.57-81
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• 2008

This paper reviewed outline of Strategic Niche Management(SNM) and its usefulness and limits as policy tool. SNM is based on Multi Level Perspective(MLP) that traces technological innovation and makes transition of lock-in socio-technical system. This approach is one of systematical then traditional one, market failure approach. SNM had get a attention not only as a analytical frame of technological development, but also tool of radical innovation, although its limits of theoretical and empirical immaturity. SNM could provide a new perspective to analysis and action within urgent needs of alternative innovation policy for aging society, news energy policy for sustainable and disaster policy in danger society.

• Journal of Science and Technology Studies
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• v.8 no.2
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• pp.109-135
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• 2008

This paper alms to analyze gender sensitiveness of national R&D projects-in the field of health- in Korea and to find a new policy which can enhance gender sensitiveness. From the gender sensitive perspective, the gender unbalanced participation in scientific research should be reconsidered, and the result of research also has to be gender balanced. In advanced countries such as european countries or United states, gender sensitive research are enforced in various ways. The NIH developed guidelines on the inclusion of women in clinical research, while the Health Canada invented a new evaluation tool of gender sensitiveness in researches. The analysis of gender sensitiveness in korean national R&D programmes showed that low number of women researchers involved in national R&D programmes, one gender oriented research subjects, and ignorance of women's specific interest in research programmes should be reconsidered and changed. In order to Improve the korean situation, not only a selection process, but also an evaluation process of performed programmes should be developed and implemented.

• Journal of Technologic Dentistry
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• v.34 no.4
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• pp.413-421
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• 2012

Purpose: The purpose of this study is to investigate the improvement measure of dental technician practical examination. Methods: A survey was performed on 111 dental technicians who were self-written questionnaire. The results were analyzed by SPSS 12.0. The collected data was analyzed by frequency and chi-square test. Results: Questions most necessary work tools with the articulator was the highest with 55.9%, Electric wax carver(16.2%), heating clear(14.4%), CAD/CAM program(9.0%) was in the order. The need for additional practical test in response to actions included maxillary and mandibular comments occlusal work that you have to wax up the highest rate of 63.8%. Items most in need of improvement was strengthen of clinically oriented(48.0%), separation of written and practical(14.6%), control the degree of difficulty(11.4%) were the next order. Conclusion: Based on the results of this study, the current dental technician did not show major problems in the practical test. However, clinicians should be strengthened mainly. To do this, the use of the articulator is essential.

• Korean Business Review
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• v.16
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• pp.123-144
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• 2003

The transfer of R&D performance is the technology transfer in a narrow sense. This study aimed at fanning the effective managerial systems of the transfer of the academic entrepreneur's R&D performance. For this purpose, this study analysed the characteristics and success factors of R&D performance transfer based on the theory of project life cycle. This research classified the life cycle of academic entrepreneurs' R&D projects into six stages. And the risks associated with the transfer process was categorized using the case study about the establishing processes the mineral-related small finns. Especially, the risk of the technology transfer was investigated by the R&D project implementation stages. Based on this results, this paper suggested the strategic system such as the marketing-oriented thinking, the clear-cut statement of the role among the stake-holders of the R&D and commercialization processes, the dynamic system of the academic entrepreneurs' leadership, the formation of the transfer management system, and the usage of project risk management techniques.

• Journal of Practical Engineering Education
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• v.12 no.1
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• pp.73-83
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• 2020

Recently, the importance of self-directed learning has emerged in the fields of public education, private education, lifelong education, and vocational training education, in which learners can actively cope with knowledge in an infusion-oriented way. However, there are various theoretical knowledge such as concepts and strategies for self-directed learning, but the situation is insufficient for a system where learners can easily receive content in the academic field they want, depending on the actual self-directed learning operation plan or learning area. Therefore, since it is important to provide various learning content in this paper, we utilize text mining techniques to obtain appropriate information and refine and categorize the meaning. On-line, they want to study a system that provides a variety of content in the academic field that learners are trying to acquire.

• Journal of Information Technology Services
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• v.19 no.2
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• pp.23-35
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• 2020

The development of digital technology is changing the paradigm of the healthcare industry to preventive and consumer-oriented. The combination of the ICT industry and the bio-healthcare industry is emerging as a core industry in the era of the Fourth Industrial Revolution. The Korean government has also selected the bio-healthcare industry as one of the three key future development industries. In May, the government announced its bio-health industry innovation strategy and set a goal of 300,000 employees. Therefore, analyzing the effects of employment on the related industries of the digital bio-healthcare industry is very important for the establishment of future industrial and technology development policies. The research method restructures the integrated classification of 32 industries into 34, including the digital bio-healthcare industry, using the classification criteria of the government and professional institutions, and then reorganizes the digital bio-healthcare industry into eight industries classified as one industry group. The analysis data was taken from the Bank of Korea's 2019 data. Various trigger coefficients and ripple effects coefficients were rewritten using the analysis method of the Input-output Statistics. The analysis of the results compares the employment-induced effects of the digital bio-healthcare industry and the ripple effects of related industries in production, investment and value-added. In addition, in terms of investment effect, the effects of in-house and related industries were compared. It is hoped that the results of this study will be used to establish employment and industrial policies.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.5
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• pp.1049-1057
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• 2017

In-vehicle multimedia systems are one of the most important factors in the automotive industry. Especially, multimedia systems are more important in advanced commercial vehicles such as premium express buses. In this paper, we proposed a multimedia streaming system architecture using MEP(MOST Ethernet Packets) for premium express buses based on MOST150. We have designed and implemented the prototype of proposed multimedia streaming system. We have designed a board based on i.MX6 to operate a proposed multimedia streaming system. The software has designed a multimedia system for premium express buses based on Android which is an open source platform. MOST(Media Oriented Systems Transport) is a high-speed multimedia network technology for in-vehicle multimedia system. The MOST network is able to manage up to 64 devices and ring topology is used basically. In addition, the MOST Network meets EMI(Electro-Magnetic Interference)/ EMC(Electro-Magnetic Compatibility) requirements because it uses plastic optical fibers(POF).

• Journal of Surface Science and Engineering
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• v.38 no.5
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• pp.193-197
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• 2005

Highly c-axis oriented Zinc oxide (ZnO) films were successfully deposited at room temperature by oxygen ion-assisted pulsed filtered vacuum arc. The effect of oxygen gas ratio ($O_{2}/O_{2}+Ar$ on the preferred orientation, surface morphology and resistivity of the ZnO films were investigated. Highly crystalline ZnO films with (002) orientation were obtained at over $13\%$ of oxygen gas ratio. Increasing oxygen gas ratio up to $80\%$ was found to improve crystallinity of the films. From hall measurements, it was found that the film has n-type characteristic and carrier concentration and its mobility were closely related with oxygen gas ratio. Minimal resistivity of $3.6{\times}10^{-3}{\Omega}{\cdot}cm$ was obtained in the range of $20\%$ to $40\%$ of oxygen gas ratio.

• Progress in Superconductivity
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• v.8 no.2
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• pp.127-131
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• 2007

We have measured the Hall conductivity (${\sigma}_{xy}$) of c-axis-oriented $MgB_2$ thin films as functions of temperatures and magnetic fields. We found that the Hall conductivity (${\sigma}_{xy}$) is expressed by the sum of two terms, ${\sigma}_{xy}=C_l/H+C_3H$, where the coefficient $C_1\;and\;C_3$ are independent of the magnetic fields and have positive values. The coefficient $C_1$ is strongly dependent on the temperature, while the $C_3$ is weakly dependent on the temperature. We have obtained that the $C_1$ is proportional to $(1- T/T_c)^n$ with n = 4.2, which is consistent with the data observed in $La_{2-x}Sr_xCuO_4$ superconductors with low anisotropy ratio.