• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.12
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• pp.1667-1675
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• 2001

Numerical simulations are carried out for the liquid encapsulant Czochralski(LEC) by imposing a magnetic field. The use of a magnetic field to the crystal growth is to suppress melt convection and to improve the homogeneity of the crystal. In the present numerical investigation, we focus on the range of 0-0.3Tesla strength for the axial and cusped magnetic field and the effect of the magnetic field on the melt-crystal interface, flow field and temperature distribution which are the major factors to determine the quality of the single crystal are of particular interest. For both axial and cusped magnetic field, increase of the magnetic field strength causes a more convex interface to the crystal. In general, the flow is weakened by the application of magnetic field so that the shape of the melt-crystal interface and the transport phenomena are affected by the change of the flow and temperature field.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37A no.12
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• pp.1031-1037
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• 2012

We study an algorithm that can efficiently find square roots and cube roots by modifying Tonelli-Shanks algorithm, which has an application in Number Field Sieve (NFS). The Number Field Sieve, the fastest known factoring algorithm, is a powerful tool for factoring very large integer. NFS first chooses two polynomials having common root modulo N, and it consists of the following four major steps; 1. Polynomial Selection 2. Sieving 3. Matrix 4. Square Root. The last step of NFS needs the process of square root computation in Number Field, which can be computed via square root algorithm over finite field.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.31 no.4
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• pp.90-104
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• 2023

This study analyzes the perceptions of college students majoring in aviation services according to the field learning program conducted during their major studies in order to reflect the educational value and academic awareness of the experience of the experiential field learning program. A survey is conducted targeting college students who experience a field learning program conducted by the Aviation Service Department of J University, a four-year university in the Chungcheong region. ANOVA (one-way analysis of variance) is conducted to analyze differences in perceptions of field learning properties, learning satisfaction, academic self-efficacy, and intention to continue studying. Additionally, text mining is conducted using 'Voyant Tools' to analyze students' field trip logs regarding field trip learning program activities. I hope that the results will be used as evidence to build an efficient and systematic learning strategy for operating field learning programs.

• International Commerce and Information Review
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• v.8 no.2
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• pp.119-139
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• 2006

The purpose of this research is to analyze four models of global e-trade implementation which was suggested at the advance research of implementation global e-Trade with major trading countries. The main outcomes of this empirical study are as follows. For realizing global e-trade of G-Networking model country we have to implement e-trade in the field of "import & logistics". And for realizing global e-trade of P-Networking model country, it need to try in "settlement & clearance". Furthermore, for realizing global e-Trade of G-Penetration model country, we have known that the field of "import & logistics" would be implemented. Finally for realizing global e-Trade of P-Penetration model country, "settlement & clearance" could be implemented. Also, this study suggests that we have to do negotiation with China and Japan at first, and to try the area of settlement & clearance to implement the global e-Trade with Korea's 10 major trading countries.

• Journal of Information Technology Services
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• v.6 no.3
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• pp.141-162
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• 2007

In this study, we conduct a case analysis on EZmedicom which is one of the leading companies in e-Marketplace for medical fields. By examining major business models of EZmedicom, we provide the success factors in launching the electronic commerce to the potential companies which are interested in participating in e-marketplace for medical fields. Especially, we deduct the solution, logistics field, and electronic group-purchasing as its major business model. Based on these factors, we also propose the MDvan solution which is one of the electronic purchase and supply system, Ezlogis that is the system supporting logistics parts in medical fields, VMI(vendor management inventory), standardization of item code and the linkage of SCM as its critical success factors of EZmedicom. The findings of this study suggest practical and managerial implications for e-Marketplace implementation in the medical field and further research.

• Progress in Superconductivity
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• v.1 no.1
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• pp.56-60
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• 1999

Ultra fine MgO particles added BSCCO tapes were fabricated by tape casting using Doctor Blade Method and enclosed by silver foil for different starting compositions (that is, 2223 major, 2212 major). In order to obtain optimum microstructure, thermomechanical treatment was done. Microstructure and phase were analyzed by XRD, SEM and DTA. The critical current density was measured under magnetic field at 77K. The tapes fabricated from the precursor powder with BSCCO-2223 phase (>90%) result in a microstructure with a larger grain size and higher transport critical current density value under magnetic field at given thermomechanical treatment conditions.

• 한국지구물리탐사학회:학술대회논문집
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• 2008.10a
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• pp.33-36
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• 2008

For the past 300 Ma, massive extinctions are associated with major flood basalt eruptions. The geomagnetic Superchrons (Cretaceous Normal Superchron, Kiaman Long Reversed Superchron, Moyero Long Reversed Superchron) precede the major flood basalt eruptions and massive extinctions. It is likely that upswing of mantle plumes is responsible for the generation of continental flood basalt. Eruption of flood basalts results in a catastrophic climate change as well as a massive genus depletion.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.3
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• pp.979-987
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• 1996

A theoretical study for the laminar round jet diffusion flame impinging on the wall was carried out to predict the characteristics and structure of impinging jet flame and heat transfer to the wall. Finite chemistry via Arrhenius equation was adopted as the combustion model. All the transport properties were considered as the variable depending on the temperature and composition. For the parametric study, the distance from nozzle to perpendicular wall and Reynolds number at nozzle exit were chosen as the major parameters. As the results of the present study, the characteristics of flow field and the distributions of temperature, density and each chemical species were obtained. The heat transfer rate from flame to the wall and the effective heating area were calculated to investigate the influence of the major parameters on the heat transfer characteristics.

• Journal of Technologic Dentistry
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• v.29 no.2
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• pp.17-34
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• 2007

This study was conducted to research into the recognition level of employment and overseas employment on 173 students majoring in dental technology at two colleges in Daegu metropolitan city and Jeju self-governing island through questionnaires which are recorded individually. The results are as follows. 1. About 31.8% students chose dental technician department taking their aptitude into consideration when they entered college. 52% students gained information about dental technology through internet, and 57.3% students among them, which was the highest level, were under age 20. 2. 48.6% students responded that they thought the level of satisfaction with major was average and there was a difference according to their ages among the level of satisfaction or dissatisfaction with their major and the previous knowledge of major they had gained before entering college. 75.1% students said they wouldn't transfer to other major even if they were given the chance, which was much higher than the opposite case. And only 2.3% students had dissatisfaction at their major, which means students majoring dental technology evaluate their major positively. 3. Most students(58.4%) wanted to get a job for living cost and 53.2% students took advice from their seniors or elderly people in choosing their jobs. 64.7% students answered they should have professional skills to get a good job, which was different according to their ages. In addition, 51.4% students of dental technology department regarded the opportunities to exert their abilities as the most important element in choosing their jobs. That means students value self-decision and selfrealization when they choose their jobs. 4. The majority of students(32.9%) preferred to work at the dental laboratory in dental college hospital as their workplace. Moreover, seniors over age 21 wanted to work in the field of porcelain and juniors under age 20 preferred to work in the implant part concerning the field which students wants to work. 5. About 91.3% students have ever heard about overseas employment and wanted to work abroad if given the opportunities(77.5%). This points out students have much interest in overseas employment and positive attitude. And there was a difference according to age and grade in case of the preferred country when they work abroad 6. The main barrier to overseas employment was a lack of communication ability(63.0%), therefore, students thought foreign language education should be activated to improve overseas employment(26.0%). To show this more specifically, juniors thought foreign language education and internship are most important factors(both are 21.4% alike), while seniors thought foreign language education is essential(24.6%) as a way to improve overseas employment. Students also thought that participation in language study club helps to prepare for overseas employment(69.4%). When putting all these survey results together, it's very important to develop people in advance who have job ability and language ability necessary for overseas employment as well as to improve job awareness in the field of dental technology. Consequently, it's needed to seek for various ways to get a overseas job through foreign language education and overseas internship.

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1315-1320
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• 2011

Whey protein (WP) is a mixture of proteins, and is of high nutritional values. WP has become an important source of functional ingredients in various health-promoting foods. In this study, size-exclusion chromatography (SEC) and asymmetrical flow field-flow fractionation (AsFlFFF) were used for separation and analysis of whey proteins. It was found that a lab-prepared WP from raw milk is mostly of ${\beta}$-lactoglobulin with small amount of higher molecular weight components, while a commercial whey protein isolate (WPI) powder contains relatively larger amount of components other than ${\beta}$-lactoglobulin, including IgG and protein aggregates. Results suggest that AsFlFFF provides higher resolution for the major whey proteins than SEC in their normal operation conditions. AsFlFFF could differentiate the BSA and Albumin, despite a small difference in their molecular weights, and also was able to separate much smaller amount of aggregates from monomers. It is noted that SEC was able to show the presence of low molecular weight components other than the major whey proteins in the WP samples, which AsFlFFF could not show, probably due to the partial loss of those low molecular weight species through the membrane.