• Communications of Mathematical Education
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• v.22 no.4
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• pp.505-514
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• 2008

In this paper we study on derivation of formulas for roots of quadratic equation, cubic equation, and quartic equation through method analogy. Our argument is based on the norm form of polynomial. We also present some mathematical content knowledge related with main discussion of this article.

• Journal of the Korean Ceramic Society
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• v.33 no.7
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• pp.743-754
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• 1996

In this study (Ba1-xPbx)TiO3 was synthesized by modified oxalate process in order to prevent vaporization of PbO through low temperature synthesis climinate Cl ion reproducibly substitute Pb for by and uniformly distribute ion (Ba1-xPbx)TiO3 was synthesized by coprecipitation of lead acetate barium acetate and ammonium titanyl oxalate have been used as starting materials. The substitution of Pb for Ba was reproducibly possible synthetic temperature of perovskite structure becomes lowed as the Pb concentration increases and fine partic-les (specific surface are :7.2 cm2/g) were obtained, BaTiO3 powders calcined at 90$0^{\circ}C$ for 3 hours were cubic from in XRD analysis and as Pb content was increases evident split of tetragonal peaks could be observed The optimum conditions to synthesize (Ba,Pb)TiO3 powder are the followings ; synthesis temperature (5$^{\circ}C$)

• The Transactions of the Korea Information Processing Society
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• v.7 no.3
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• pp.872-878
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• 2000

In this paper a computer programming for the expression of nearest neighbor atoms in face-centered cubic (FCC) and body-centered cubic (BCC) crystals was suggested as one of the approaches to understand each of the crystal structure. By using this computer programming the distance values between a reference atom and the nearest neighbor atoms, and the numbers of the nearest neighbor atoms were calculated ane compared for the FCC and BCC crystals. In this algorithm, the positions of the atoms in a crystal were defined as two categories: the corner atoms and face- or body-centered atoms, and considered respectively. For the same order of nearest neighbor atoms except the second order ones the distance values form the reference atom were smaller in the FCC crystals than those in the BCC. Also, the numbers of he first and third nearest neighbor atoms n the FCC crystals were larger than those in the BCC. This difference was explained by the comparison of each atomic packing ratio of the FCC and BCC crystals. The algorithm used in this programming can also be expanded to the analysis of other crystal structures.

• Earthquakes and Structures
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• v.2 no.4
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• pp.323-336
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• 2011

The problem of reconstruction of complete building response from a limited number of response measurements is considered. The response at the intermediate degrees of freedom is reconstructed by using piecewise cubic Hermite polynomial interpolation in time domain. The piecewise cubic Hermite polynomial interpolation is preferred over the spline interpolation due to its trend preserving character. It has been shown that factorization of response data in variable separable form via singular value decomposition can be used to derive the complete set of normal modes of the structural system. The time domain principal components can be used to derive empirical transfer functions from which the natural frequencies of the structural system can be identified by peak-picking technique. A reduced-rank approximation for the system flexibility matrix can be readily constructed from the identified mass-orthonormal mode shapes and natural frequencies.

• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.1
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• pp.28-37
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• 2022

The burning rate estimation method of solid propellants, based on closed bomb tests, has been introduced. The composition of the combustion gas is determined by using CEA and the Noble-Abel equation of state for high pressure operation conditions. Covolume taking into account the collision among molecules due to the actual volume of the molecule is modeled by LJ potential. A cubic form function is applied to calculate the volume change of propellant grains during combustion. The estimated burning rates of five different grain configuation at high pressure are fairly compared with BRLCB results within the maximum error of 6%.

• Korean Institute of Interior Design Journal
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• no.25
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• pp.169-175
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• 2000

Since the late 19th Century, modern architecture of definite figure and form shared similar concepts on space and from with the abstract art, pursuing the geometric purity and the abstraction. So the reductive approach had been taken in modern architecture as well as on modern art. The 1960 minimal art had experimented an extreme reduction with the cubic forms and the plane canvases, embodying so called minimal-art content, it was just another version of modernism art interpreted by the extreme reduction. The reduction is a characteristics of modernism adopted in every art field, including architecture. Not from the apparent, but from the essential quality of architectural form, figure and space resulting from the reductive approach, a building in this trend schould be judged and appreciated. In many aspects, Korean traditional architecture has been shown the characteristics of Minimal Architecture. With these points of view, this study analyzes characteristics of Korean traditional architecture with above contents through the form and space.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.7
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• pp.976-986
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• 2000

The purpose of this study is to clarify the relationship between the visual sensibility and the decorative design of clothing. 41 kinds of costume samples have been selected from photographs in fashion magazines under detail and trimming, and divided into three types according to line, shape, and form. I have measured these images by using Semantic Differential method. The obtained data were analyzed by factor analysis ANOVA, discriminant analysis, regression analysis and MDS. The results of analysis are as follow; 1. Factor analysis has extracted five factors which consist of decorative design sensibility. These factors are Attractiveness, Hardness and Softness, Rhythm, Decorativeness, Cuteness. 2. There were significant differences in visual evaluation of decorative design and demographics 3. The discrimination among formative designs was closely related to decorative image, especially between line and form. 4. The Image effect on Preference, Buying needs, Riches and Pleasant was consist of complicated sensibility. 5. Evaluative dimensions of decorative design were identified by Simple-Complicated, Cubic -Plane perceptive image differed in degree of similarity in spite of same formative design.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.04a
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• pp.315-320
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• 2001

Ultra-abrasives such as diamond and CBN have used to maintain accuracy and form deviation for superalloy etc. This study contains the dry cylindrical grinding of metals with Vitrified-bond CBN wheel and Resinoid-bond CBN wheel. For various condition of grinding speed, workpiece speed, grinding depth and feed speed of table, the grinding resistance, the surface roughness, and material removal are measured and discussed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.298-302
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• 1994

A three dimensional FE mesh generation scheme based on mapping approach is proposed in this study. A volume in Euclcdian space is represented by composite hyperpatches which are piecewise cubic functions with parameters u,v,w. A key idea in the proposed approach is that sampled grid data points only on the boundary surfaces are needed for the shape representation. Inner points which are necessary of form a hyperpatch are internally generated by Coons patches. This approach is most appropriate for the shapes which are compositions of hexahedron-like shapes and also severely curved.

• Journal of the Korean Society of Costume
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• v.51 no.3
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• pp.111-127
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• 2001

This study aims to apply the formative aesthetic of human body to the form of clothing. For this purpose I try to find the various methods of analysis used in the work of sculpture. The method of inference and the checklists of design are used to relate the sculpture with the clothing design specifically. This methodology intends to regard human body as an artistic form and use the image of sculpture to the maximum. Especially I try to derive the motives of design and recreate them in clothing design emphasizing silhouette. On this methodology, following results were developed. First, the observations on the formative characteristic of human body show that the transformed form of human body expresses more perfect image of human body than the original form. The power of simplicity heightens the total beauty of the work. Second, the image of human body expressed in simplicity heightens the total beauty of the work. Second, the image of human body expressed in simplicity and exaggeration can be variously recreated in a silhouette with the formative and cubic effect, simplicity, and activity. Third, the elegant and static image found in the analysis and synthesis of human body can be used as a motive of clothing design and the changed details lead to the transformation of silhouette. Fourth, in developing designs by the item of checklists, one motive can be variously recreated according to the methods of designs.