• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.561-564
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• 2006

Because of new requirements related to the employment of SMT(Surface Mounting Technology) manufacturing and the diversity of components on high density PCB(printed circuit boards), Thermal control of the reflow process is required in oder to achieve acceptable yields and reliability of SMT assemblies. Accurate control of the temperature distribution during the reflow process is one of the major requirements, especially in lead-free assembly. This study has been performed for reflow process using the commercial CFD tool(Fluent) for predicting flow and temperature distributions. There was flow recirculation region that had a weak point in the temperature uniformity. Porous plate was installed to prevent and minimize flow recirculation region for acquiring uniform temperature in oven. This paper provided design concept from CFD results of the steady state temperature distribution and flow field inside a reflow oven.

• Journal of Ship and Ocean Technology
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• v.8 no.2
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• pp.20-28
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• 2004

A dynamic-thermodynamic sea ice model with 50-km spatial and 24-hour temporal resolution is used to investigate the spatial and long-term temporal variability of the sea ice cover the Arctic Basin. The model satisfactorily reproduces the averaged main characteristics of the sea ice and the sea ice extent in the Arctic Basin and its decrease in early 1990th. At times model allows to suppose partial recovery of sea ice cover in the last years of twenty century. The employment of explicit form for description of ridging gives opportunity to assume that the observed thinning is the result of reduction the intensity of ridging processes and to estimate long-term variability of probability the ridge free navigation in the different parts of the Arctic Ocean including the North Sea Route area.

• Structural Engineering and Mechanics
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• v.76 no.1
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• pp.129-139
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• 2020

In this piece of work, carbon nanotubes motion equations are framed by Kelvin's method. Employment of the Kelvin's method procedure gives birth to the tube frequency equation. It is also exhibited that the effect of frequencies is investigated by varying the different index of polynomial function. By using volume fraction for power law index, the fundamental natural frequency spectra for two forms of single-walled carbon nanotubes are calculated. The influence of frequencies against length-to-diameter ratios with varying power law index are investigated in detail for these tubes. Throughout the computation, it is observed that the frequency behavior for the boundary conditions follow as; clamped-clamped, simply supported-simply supported and these frequency curves are higher than that of clamped-free curves. Computer software MATLAB is utilized for the frequencies of single-walled carbon nanotubes.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.10a
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• pp.295-302
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• 2001

In the present study, we propose the framework which directly links shell finite element to the surface geometric modeling. For the development of a robust shell element, partial mixed variational functional is provided. The NURBS is used to generate the general free form of parameterized shell surfaces. Employment of NURBS makes shell finite element handle the arbitrary geometry of the smooth shell surfaces. The proposed shell finite element model linked with NURBS surface representation provides efficiency for design and analysis and can be directly extended to surface shape optimization problems in future work.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.04a
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• pp.505-511
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• 2002

In the present study, we visualize the linkage framework between geometric modeling and shell finite element based on B-spline representation. For the development of a consistent shell element, geometrically exact shell elements based on general curvilinear coordinates is provided. The NUBS(Non Uniform B-Spline) is used to generate the general free form shell surfaces. Employment of NUBS makes shell finite element handle the arbitrary geometry of the smooth shell surfaces. The proposed shell finite element .model linked with NUBS surface representation provides efficiency for the integrated design and analysis of shell surface structures. The linkage framework can potentially provide efficient integrated approach to the shape topological design optimizations for shell structures.

• Journal of the Korean Ceramic Society
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• v.56 no.1
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• pp.1-23
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• 2019

Dielectric materials with inherently high power densities and fast discharge rates are particularly suitable for pulsed power capacitors. The ongoing multifaceted efforts on developing these capacitors are focused on improving their energy density and storage efficiency, as well as ensuring their reliable operation over long periods, including under harsh environments. This review article summarizes the studies that have been conducted to date on the development of high-performance dielectric ceramics for employment in pulsed power capacitors. The energy storage characteristics of various lead-based and lead-free ceramics belonging to linear and nonlinear dielectrics are discussed. Various strategies such as mechanical confinement, self-confinement, core-shell structuring, glass incorporation, chemical modifications, and special sintering routes have been adopted to tailor the electrical properties and energy storage performances of dielectric ceramics. In addition, this review article highlights the challenges and opportunities associated with the development of pulsed power capacitors.

• East Asian Economic Review
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• v.26 no.2
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• pp.95-117
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• 2022

This paper empirically examines what factors affected the termination of anti-dumping measures in Korea during the 2006-2019 period. Employing a meticulous literature review, the paper investigates the WTO's and Korea's rules on the termination of anti-dumping measures and sets up the related variables in the Cox proportional hazards model. The empirical results show that the GDP growth rate, employment, and trade competitiveness in domestic industries had positive effects on the hazard of the termination of AD measures, while free trade agreements had negative effects. By industry, the hazard of the termination of AD measures was less prominent in the steel industry, while it was more prominent in the machinery industry. These results imply that AD measures in Korea had the properties of a proper trade remedy policy and, at the same time, a protectionism tool to sustain its domestic industries, depending on industrial characteristics and other trade policies.

• Journal of Engineering Education Research
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• v.25 no.4
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• pp.13-20
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• 2022

The purpose of this study is to objectively grasp the effect of the engineering education innovation support project among the national engineering-related financial support projects by dividing the groups according to the participation of support projects from 2018 to 2020 and dividing the university performance. As a result of the research the engineering education innovation support project has been consistently producing excellent results of field-based engineering education such as field-oriented industrial-educational collaboration capstone design, technology commercialization, and development and operation of corporate-linked education. It was found that the results showed that the dropout rate of college were lowered. In the future, it needs to be prepared as a place for new and free trials, innovations, and opportunities so that the engineering education innovation support projects can become the mother of other business groups.

• The Journal of Economics, Marketing and Management
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• v.3 no.1
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• pp.23-32
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• 2015

Present monetary system is based on fallacies. The purpose of this article is to highlight the pitfalls in economic thinking. The article shows that this way of thinking leads to the creation of inflation which is the root of all evil. The analysis proceeds in different approach to the contemporary theory of money. An inflation- free monetary system is introduced. Monetary system is the set of mechanisms that controls money. In this broad sense, monetary system can be divided into three different systems. Each of them has different goal; National monetary system which aims to raise sufficient funds in order to reach an optimal level of output growth that maintains full employment and satisfies the economic requirements of the community. National redistribution system which aims to redistribute funds in order to sustain individuals at or above a specified material standard of living, and enable government to provide public services. International monetary system which aims to preserve rights of parties in foreign exchange transactions.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.17 no.1
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• pp.41-67
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• 2006

The study is aimed to analyze the influence of FTA(Free Trade Agreement) between Korea and Japan on tourism and to suggest ways to increase tourists exchange between them by considering countermeasures of Korea's tourism based on the analysis and deriving political significance. The results of the study showed that the expected effects of FTA between Korea and Japan on tourism would overall be positive. There would be increases in employment and a higher rate of foreign-exchange earning, which plays a critical role in the cash flow. Therefore the government is required to prepare for several political measures as follows. First, ways to promote investment in tourism have to be established in a systematic way for FTA. Second, restructuring of tourism has to be considered seriously for tourism to be a high value-added industry after FTA. Third, the tourism information industry needs to be included in the tourism promotion act to promote e-tourism using information technology. In addition to this, an expansive cluster strategy needs to be developed, which relates tourism to other industries like culture and movies and to find ways to re-locate and re-educate manpower currently engaged in the tourism industry. Though the study investigated the influence of FTA on tourism through a practical analysis, it was restricted only to Korea. So the influence of FTA between Korea and Japan on the tourism of Japan should be included in further study. Furthermore, in subsequent studies the CGE(Computable General Equilibrium) model will be applied for objective analysis of the effects. Or measuring the ripple effect with multinational inter-industry relation table will be made for the study to make practical contributions to the development of government policy.