• Journal of Theoretical and Applied Mechanics
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• v.1 no.1
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• pp.29-67
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• 1995

A procedure is formulated, in this paper, to compute the bifurcation modes born by the stability change of normal modes, and to compute the forced responses associated with bifurcation modes in inertially and elastically coupled nonlinear oscillators. It is assumed that a saddle-loop is formed in Poincare map at the stability chage of normal modes. In order to test the validity of procedure, it is applied to one-to-one internal resonant systems in which the solutions are guaranteed within the order of a small perturbation parameter. The procedure is also applied to the exact system in which normal modes are written in exact form and the stability of normal modes can be exactly determined. In this system the stability change of normal modes occurs several times so that various types of bifurcation modes are created. A method is described to identify a fixed point on Poincare map as one of bifurcation modes. The limitations and advantage of proposed procedure are discussed.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.288-292
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• 2006

Usually, equations that calculate ground resistance of earth electrode was already informed well by form of earth electrode. But, when apply on the spot because general expressions are very insufficient at point that calculate exact ground resistance value by variation of earth electrode, and constant value that corrective coefficient for ground resistance calculation is fixed regardless of change of the earth resistivity specially is presented, it is actuality that difficulty is. Therefore, in this study, about these problem, proposed corrective coefficient for calculation of ground resistance according to change of the earth resistivity.

• Journal of the Korean Institute of Rural Architecture
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• v.3 no.2
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• pp.1-12
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• 2001

This study is about the residential district structure of Gyeryong ceramic art village in Gyeryong ceramic art village is a residential district for potters who succeed to and develop Gyeryong ceramic art. The external appearance of Gyeryong ceramic art village seems like being fixed and simplified. The creative space is either detached or attached to a living room. The relation between inner and outer space is that is directly connected to a garden. In the characters of major spaces, the formation of a workshop is the most important part of a house. And, an exhibition equipment and an oven are connected to the workshop. According to the study, a house, which is designed without an architect's help is simple and has a different form from a house designed by an architect.

• Journal of Information Management
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• v.22 no.2
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• pp.29-46
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• 1991

This study intends to compare the structure of the record and the methods of content designation of the MARC formats based on UNIMARC, USMARC, KOMARC, CHINESE MARC and JAPAN MARC. The structure of the formats takes the similar form to base on ISO 2709. The methods of content designation of the fixed fields is analyzed into 6 categories. And of the content designators, JAPAN MARC does not use indicator.

• Nuclear Engineering and Technology
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• v.32 no.5
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• pp.457-464
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• 2000

In this paper, we describe the results of various calculations performed for a design of the thickness gauges that use the gamma-ray backscattering method. The radiation source is assumed to be the $_{24}$1Am(60keV gamma-ray) and the detector is a single crystal scintillator in a cylindrical form. The source is located at the center of the detector with the collimator of a cylindrical shape. First, when gamma-rays are incident on a material with a constant angle, we compute the variations of the spectrum for the photons scattered into different angular intervals. Next, we compute for an optimal size for the collimator cylinder for a fixed detector size and an optimal distance from the detector to the material. Finally, we compute the number of observed photons for different thickness of two different materials, a plastic film and an Al foil.

• Land and Housing Review
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• v.11 no.1
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• pp.59-66
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• 2020

This thesis investigates relationship between Stock-to-Flow price and housing starts in Seoul metropolitan form 2008 year to 2019 year. The paper tests the relationship through two time-series models such as a vector error correction model and Dynamic Panel regression model. The model results show evidence of positive correlation between Stock-to-Flow price and housing starts in the long run. By transforming the regional data into a panel data set and running a fixed effects model, we test the explanatory power of PBR on housing starts. The result of VECM confirms that one unit uprising PBR raises up apartment construction by 7.4%. This result supports that PBR is a major factor in choosing a start of housing construct. Base on the result of empirical model, We also suggest that the market self-regulation function of housing providers is operating in the entire metropolitan area market.

• Journal of Technology Innovation
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• v.13 no.3
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• pp.131-151
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• 2005

Industrial Technology Development Program enables the recipient to set up technology infrastructure and to facilitate technology diffusion. In return, government charges royalty from the program recipient. However, the current royalty system is not in the effective form. This study analyzes the various aspects of royalty collection methods applied to the Industrial Technology Development Program and recommend the following: (1) employ the combination of fixed amount royalty and running royalty with predetermined portion of revenue generated, (2) adjust the royalty collection duration by applying product life cycle, and (3) devise new program to link extra-gain from royalty collection with commercialization and other means to increase the effectiveness of research and development activities.

• Journal of Institute of Convergence Technology
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• v.6 no.1
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• pp.1-5
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• 2016

Additive manufacturing is converting a digitally designed object into a tangible three dimensional solid using an additive process where materials are applied in successive layers with no or very limited material waste. It can be distinguished form traditional manufacturing which begins with a fixed amount of raw material and removes excess to arrive at the final product. Generally there are five stages to the additive manufacturing supply chain, namely materials, systems, software, application design and production. In this paper, recent market trends and technology about additive manufacturing based on supply chain are analyzed and reviewed.

• Communications of the Korean Mathematical Society
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• v.30 no.4
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• pp.505-513
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• 2015

The present paper deals with the determination of displacement and thermal stresses in a semi-infinite circular cylinder defined as $0{\leq}r{\leq}b$, $0{\leq}z<{\infty}$, due to internal heat generation within it. A circular cylinder is considered having arbitrary initial temperature and subjected to time dependent heat flux at the fixed circular boundary (r = b) whereas the zero temperature at the lower surface (z = 0) of the semi-infinite circular cylinder. The governing heat conduction equation has been solved by using integral transform method. The results are obtained in series form in terms of Bessel functions. The results for displacement and stresses have been computed numerically and illustrated graphically.

• Journal of the Korean Mathematical Society
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• v.58 no.1
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• pp.109-122
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• 2021

In this paper, we consider the problem of finding the hypersurface Mn in the Euclidean (n + 1)-space ℝn+1 that satisfies an equation of mean curvature type, called singular minimal hypersurface equation. Such an equation physically characterizes the surfaces in the upper half-space ℝ+3 (u) with lowest gravity center, for a fixed unit vector u ∈ ℝ3. We first state that a singular minimal cylinder Mn in ℝn+1 is either a hyperplane or a α-catenary cylinder. It is also shown that this result remains true when Mn is a translation hypersurface and u is a horizantal vector. As a further application, we prove that a singular minimal translation graph in ℝ3 of the form z = f(x) + g(y + cx), c ∈ ℝ - {0}, with respect to a certain horizantal vector u is either a plane or a α-catenary cylinder.