• The Pure and Applied Mathematics
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• v.17 no.1
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• pp.81-86
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• 2010

This paper gives some sorts of weakly cancellative of elements which are to be or not to be left magnifying elements in certain semigroups and gives a semilattice congruence in a weakly separative semigroup.

• Korean Journal of Mathematics
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• v.27 no.2
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• pp.269-277
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• 2019

Let X be a nonempty set, ${\rho}$ be an equivalence on X, T(X) be the semigroup of all transformations from X into itself, and $T_{\rho}(X)=\{f{\in}T(X)|(x,y){\in}{\rho}{\text{ implies }}((x)f,\;(y)f){\in}{\rho}\}$. In this paper, we investigate some necessary and sufficient conditions for elements in $T_{\rho}(X)$ to be left or right magnifying.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.733-736
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• 2003

This paper presents two systems of two-stage electrohydraulic servovalve with a nozzle-flapper pilot stage, which is controlled by stack-type piezoelectric elements. Two flapper moving mechanisms proposed in this research can compensate for the hysteresis problem and thermal expansion of the piezoelectric elements. The experimental results show that the first flapper moving mechanism has the frequency response of over 500 Hz and the second one has the response of over 600 Hz. And the first simplified servovalve system rising the first flapper moving mechanism has the frequency response of about 150 Hz, and the second system has the response of about 300 Hz at the supply pressure of 210 bar

• Journal of the Korean Society for Precision Engineering
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• v.20 no.6
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• pp.71-80
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• 2003

This paper presents a two-stage electrohydraulic servovalve with a nozzle-flapper pilot stage, which is controlled by stack-type piezoelectric elements. The flapper moving mechanism developed in this research can compensate for the hysteresis problem and thermal expansion of the piezoelectric elements. The experimental result shows that this flapper moving mechanism has the frequency response of about 600 Hz. And a simplified servovalve system using this flapper moving mechanism has the frequency response of about 300 Hz at the supply pressure of 210 bar.

• International Journal of Precision Engineering and Manufacturing
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• v.4 no.6
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• pp.29-37
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• 2003

This paper presents a two-stage electrohydraulic servovalve with a nozzle-flapper pilot stage, which is controlled by stack-type piezoelectric elements. The flapper moving mechanism developed in this research can compensate for the hysteresis problem and thermal expansion of the piezoelectric elements. The experimental result shows that this flapper moving mechanism has the frequency response of about 600 Hz. And a simplified servovalve system using this flapper moving mechanism has the frequency response of about 300 Hz at the supply pressure of 210 bar.

• The Research Journal of the Costume Culture
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• v.8 no.1
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• pp.87-101
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• 2000

The purpose of study is explaining the Historicism as a result of compromise, historical eclecticism, between historical things and current cultural background instead of regarding it as an imitation from the past. It means that external factors in history help internal esthetic value surface out as costume. Fashion s history is more than the classified thing according to the appearance with the changes of the times. Intrinsic cultural elements should be added in creating new fashion. One of the different features between Modernism and Post-modernism. When coming to the period of Post-modernism, it connected with the historical factors to make something new by fragmenting, magnifying, or minimizing them. This is calles 'Historicism'in the world of art. It revived the past, not the past itself, in new ways : quotation, reuse, metaphor, and mixture. To represent the image, parody, pastiche, or bricolage was usually used. In post-modernism fashion, parody is a technique for imitating the past or the preceding forms with artists'own critical points of view. This technique gives us shock or surprise by using satirical, ironical or paradoxical expressions. pastiche shares the same part with parody in imitating particular or unique style, and it can be renamed empty parody, because it doesn't have any hidden motivation or satirical impulse. bricolage is a mixture of quotations from other works. It contains fragments that deepen the image. Like the techniques uttered above, the revival of history through parody, pastiche or bricolage is historical eclecticism and it is included in Historicism.

• The Journal of Korean Medicine
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• v.25 no.1
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• pp.161-171
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• 2004

Objectives: Sasang Constitutional Medicine is popularly appliedto treatment in Korea. Constitution is a holistic concept contained internal and external characteristics, and physical traits including ordinary symptoms. Skin is one of constitutional property elements. So we researched a correlation female facial skin and sasang constitution. This is a basic study to find constitution can be a major factor to care and manage skin. Methods: We examined sasang constitution and facial skin condition of 100 healthy women who aged from 30 to 59. Hydration and sebum of facial skin was measured by skin diagnostic instrument and skin type was calculated from the data. Keratin, pore size, acne, and brightness of face was measured by skin magnifying lens and subjective skin troubles in ordinary times was also investigated. Constitution diagnosis and Skin diagnosis was investigated separately as a blind test andthe data was statistically analyzed with chi-square test, Correlation analysis, One-way analysis of variance. Results: 1. In sasang constitution, Taeeumingroup bad significant tendencies of larger hydration and sebum amount, combination degree of forehead and cheek was also higher than other constitutions(p<0.05). 2. Facial skin type was significantly different according to Sasang Constitution, Soeumin and Soyangin had a tendency of dry skin comparatively, but Taeeumin had mainly a tendency of combination skin and secondly dry skin(p<0.05). On the other hand, there was no correlation between age and skin type. 3. In subjective skin trouble, Soeumin group had less acne trouble than Soyangin and Taeeumin group(p<0.1). Pore size trouble was more frequent in Soyangin group than Soeumin group(p<0.05). Keratin trouble was more frequent in Soeumin group than Soyangin and Taeumin group(p<0.1). Conclusions: Korean healthy women's skin condition was different according to sasang constitution.

• Applied Microscopy
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• v.39 no.1
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• pp.41-48
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• 2009

We investigated the morphological characteristics of the pearlescent pigment by using scanning electron microscope, energy dispersive X-ray spectrometry and thermal analyzer. The result is that the shape of pigment is platy polygonal form through observing the pearlescent pigment by the scanning electron microscope. The size of pigment is various and not formed in standardized size or shape. The pigment flakes were measured about from $30{\mu}m$ to $300{\mu}m$. The tip of the piece of pigment is pointed shape or angled. The result of observing them by the scanning electron microscope in magnifying high power is that the edge and the lateral face of them is an round form and the measurement of thickness is about $9{\mu}m$. As well using the high magnification scanning electron microscope, the surface of the pigment flake observed like rugged as coating with the $TiO_2$ element, the diameter of the coating particle is around 60 nm, then the coating particle consists of granular substance. Analysis of the configuration elements of pearlescent pigment using by the energy dispersive X-ray spectrometry is that O, Si, C, Na, Ca, Ti, Zn detected in the surface of pigment and its lateral face identifies similar components. In thermal analysis, there are no contained quantity differences between them in beginning from $100^{\circ}C$ to $800^{\circ}C$ showing thermal analysis, 1.1% out of contained quantity reduced at $115^{\circ}C$, 1.7% dropped at $416^{\circ}C$, and 1.9% decreased at $797^{\circ}C$.