• Bulletin of the Korean Mathematical Society
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• v.54 no.6
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• pp.2053-2063
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• 2017

In this paper we prove a condition under which a hyperbolic starshaped set has a center of hyperbolic symmetry. We also give the definition of isometric diameters for a hyperbolic convex set, which behave similar to affine diameters for Euclidean convex sets. Using this concept, we give a definition of constant hyperbolic width and we prove that the only hyperbolic sets with constant hyperbolic width and with a hyperbolic center of symmetry are hyperbolic discs.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.04a
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• pp.74-74
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• 2005

• Journal of the Korean Mathematical Society
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• v.43 no.6
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• pp.1253-1268
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• 2006

We develop the upper and lower solutions method for the four point problem relative to second order differential equations in order to obtain the existence of solution.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.219-220
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• 2003

나일론 6의 열변형온도와 탄성률을 증가시키는 동시에 높은 기체 차단성을 얻기 위하여 Na-montmorillonite (Na-MMT) 또는 유기화제로 개질된 MMT (organo-MMT)를 나일론 6과 melt-compounding함으로써 나일론 6 분자쇄가 MMT 층 내로 intercalation하거나 MMT의 각 층을 완전히 exfoliation시켜 나일론 6/MMT 나노복합체를 제조하는 방법과 Na-MMT 또는 organo-MMT의 존재하에서 $\varepsilon$-caprolactam (CL)을 in situ 중합함으로써 대부분의 MMT가 각각의 층으로 exfoliation 되도록하여 나일론 6/MMT 나노복합체를 제조하는 방법이 널리 쓰이고 있다 [1-2]. (중략)

• Bulletin of the Korean Chemical Society
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• v.30 no.7
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• pp.1628-1630
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• 2009

• Korean System Dynamics Review
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• v.6 no.2
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• pp.37-52
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• 2005

Conflict resolution in decision-making groups is studied using a System Dynamics model. The model is developed using a grounded-theory approach. Some preliminary results are shown. The results seem to be in line with much empirical research done in the management literature about conflict and conflict resolution at the group level of analysis. Ideas for further research are discussed.

• Proceedings of the Korean Vacuum Society Conference
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• 2006.08a
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• pp.92-92
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• 2006

• Structural Engineering and Mechanics
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• v.41 no.2
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• pp.183-204
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• 2012

Several issues regarding the structural idealization of steel buildings with perimeter moment resisting steel frames (MRSFs) and interior gravity frames (GFs) are studied. Results indicate that the contribution of GFs to the lateral structural resistance may be significant. The contribution increases when the stiffness of the connection of the GFs is considered and is larger for inelastic than for elastic behavior. The interstory shears generally increase when the connections stiffness is taken into account. Resultant stresses at some base columns of MRSFs also increase in some cases but to a lesser degree. For columns of the GFs, however, the increment is significant. Results also indicate that modeling the building as planes frames may result in larger interstory shears and displacements and resultant stresses than those obtained from the more realistic 3-D formulation. These differences may be much larger when semi-rigid (SR) connections are considered. The conservativism is more for resultant stresses. The differences observed in the behaviour of each structural representation are mainly due to a) the elements that contribute to strength and stiffness and b) the dynamics characteristics of each structural representation. It is concluded that, if the structural system under consideration is used, the three-dimensional model should be used in seismic analysis, the GFs should be considered as part of the lateral resistance system, and the stiffness of the connections should be included in the design of the GFs. Otherwise, the capacity of gravity frames may be overestimated while that of MRSFs may be underestimated.

• Steel and Composite Structures
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• v.17 no.4
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• pp.471-495
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• 2014

The responses of steel buildings with perimeter moment resisting frames (PMRF) with medium size columns (W14) are estimated and compared with those of buildings with deep columns (W27), which are selected according to two criteria: equivalent resistance and equivalent weight. It is shown that buildings with W27 columns have no problems of lateral torsional, local or shear buckling in panel zone. Whether the response is larger for W14 or W27 columns, depends on the level of deformation, the response parameter and the structural modeling under consideration. Modeling buildings as two-dimensional structures result in an overestimation of the response. For multiple response parameters, the W14 columns produce larger responses for elastic behavior. The axial load on columns may be significantly larger for the buildings with W14 columns. The interstory displacements are always larger for W14 columns, particularly for equivalent weight and plane models, implying that using deep columns helps to reduce interstory displacements. This is particularly important for tall buildings where the design is usually controlled by the drift limit state. The interstory shears in interior gravity frames (GF) are significantly reduced when deep columns are used. This helps to counteract the no conservative effect that results in design practice, when lateral seismic loads are not considered in GF of steel buildings with PMRF. Thus, the behavior of steel buildings with deep columns, in general, may be superior to that of buildings with medium columns, using less weight and representing, therefore, a lower cost.

• Journal of Microbiology and Biotechnology
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• v.19 no.9
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• pp.1005-1012
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• 2009

Lysozyme and the reduction of metabisulfite addition to red wine were evaluated during a winemaking process and after malolactic fermentation (MLF). Treatment, with lysozyme, of the must from Tempranillo grapes and at the end of alcoholic fermentation (AF) caused the 100% implantation of the inoculated bacterial strain and shortened the duration of MLF by 7 days. At the end of the MLF, wines treated with lysozyme showed lower volatile acidity, color intensity, and biogenic amine content. The differences in color intensity disappeared during wine stabilization. The lysozyme addition after MLF led to lower histamine concentrations in wines. These phenomena occurred irrespective of the lactic acid bacteria (LAB) proliferation control and of the Oenococcus oeni dominant strain identified at this period. The results of this study show the significance of preventive use of lysozyme in vinification of red wine to maintain low histamine levels and ensure a successful implantation of inoculated O. oeni starters.