• Journal of the Korean Magnetics Society
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• v.9 no.5
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• pp.251-255
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• 1999

NiFe(60 $\AA$)/Co(0$\AA$$\leq$x$\AA$$\leq$15$\AA$)/Cu(60$\AA$)/Co(30$\AA$) spin valve thin films were prepared on 4$^{\circ}$ tilt-cut Si(111) substrates with a 50 $\AA$ thick Cu underlayer without applying any external magnetic field during the deposition, and the effects of inserted ultrathin Co layer on magnetic anisotropy and GMR properties of the NiFe(60 $\AA$)/Cu(60$\AA$)/Co(30$\AA$) spin valves were investigated. As the ultrathin Co layer was inserted into the NiFe/Cu interface of the spin valves, GMR ratio was increased from about 1.5% to 3.5%, and the easy axis of NiFe(60 $\AA$) layer was rotated by 90$^{\circ}$. Accordingly, it was aligned along the same direction with the easy axis of Co(30 $\AA$)layer. Therefore, squared R-H curves was obtained in the spin valves, which is favorable properties for the digital GMR devices such as MRAM. In order to investigate the change of magnetic anisotropy of NiFe layer of the spin valves in more details,XRD measurement was performed using NiFe(500 $\AA$) and NiFe(500 $\AA$)/Co(10 $\AA$) thin films on the same templates. Strong (220) NiFe peak was observed in both films regardless of the inserted Co layer, so it was thought that the variation of magnetic anisotropy of NiFe layer is from the interface effect, the change of interface from NiFe/Cu to NiFe/Co, rather than the volume effect such as the change of magnetocrystalline effect.

• Korean Journal of Materials Research
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• v.10 no.4
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• pp.270-275
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• 2000

The Pt/YMnO$_3$/Y$_2$O$_3$/Si structure for metal/ferroelectric/insulator/semiconductor(MFIS)-FET was fabricated and effect of $Y_2$O$_3$layer on the properties of MFIS structure was investigated. The $Y_2$O$_3$ thin films on p-type Si(111) substrate deposited by Pulsed Laser Deposition were crystallized along (111) orientation irrespective of the deposition temperatures. Ferroelectric YMnO$_3$ thin films deposited directly on p-type Si (111) by MOCVD resulted in Mn deficient layer between Si and YMnO$_3$. However, YMnO$_3$ thin films having good quality and stoichiometric composition can be obtained by adopting $Y_2$O$_3$ buffer layer. The memory window of the $Y_2$O$_3$thin films with YMnO$_3$ film is greater than that of the YMnO$_3$ thin films without $Y_2$O$_3$ film after the annealing at 85$0^{\circ}C$ in vacuum ambient(100mtorr). The memory window is 1.3V at an applied voltage of 5V.

• Journal of Sericultural and Entomological Science
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• v.36 no.2
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• pp.138-146
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• 1994

The structural characteristics of Antheraea yamamai and Antheraea pernyi silk were investigated by using x-ray diffraction method, IR spectroscopy and polarizing microscopy. The amino acid composition, fiber density, thermal decomposition temperature and glass transition temperature were also measured for relating these physical properties to the structure in comparison with those of Bombyx mori silk fiber. There was no significant structural difference between A. yamamai and A. pernyi silk fiber on an examination of x-ray diffraction curve and IR spectrum. Both of these wild silk fibers showed double diffraction peaks at the Bragg angle 2Θ16.7˚ and 20.5˚by x-ray diffraction analysis as well as IR absorption peaks for the bending vibration of specific groups related to ala-ala amino acid sequence. On the other hand, the x-ray diffraction curve and IR spectrum of Bombyx mori silk fiber are different from those of wild silk fibers, indicating different crystal structure as well as amino acid sequences. It showed under the polarizing microscope examination that the birefringence and optical orientation factor of wild silk fibers are much lower than those of B. mori silk. Also, the surface of degummed wild silk fibers was characterized by the longitudinal stripes of microfibrils in the direction of fiber axies. The amino acid composition, which is strongly related to the fine structure and properties, was not significantly different between these two wild silk fibers. However, the alanine content was somewhat less and polar amino acid content more for A. yamamai. As a result of fiber density measurement, the specific gravities of B. mori, A. pernyi and A. yamamai were 1.355~1.356, 1.308~1.311, 1.265~1.301g/㎤ in the order, respectively. The calculated crystallinity(%) was 64% for B. mori and 51~52% for wild silk fibers, which showed same trend by IR method in spite of somewhat higher value. The thermal decomposition behaviour was examined by DSC and TGA, showing that the degradation temperature was in the order of B mori, A. prernyi and A. yamamai at around 350$^{\circ}C$. It was also observed by TGA that the decomposition seems to proceed step by step according to their specific regions in the fiber structure, resulting the difference in their thermal stabilities. The glass transition temperature was turned out to be 220$^{\circ}C$ for B. mori, 240$^{\circ}C$ A. yamamai and 255$^{\circ}C$ A. pernyi by the dynamic mechanical analysis. It is expected that the chemical properties are affected by the dynamic mechanical behavior in accordance with their structural characters.

• Journal of the Korean Magnetics Society
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• v.17 no.1
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• pp.18-21
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• 2007

The hexagonal $HoMn_{1-x}-Fe_xO_3$(x=0.00, 0.05) thin films were prepared using pulsed laser deposition(PLD) method on $Pt/Ti/SiO_2/Si$ substrate. The microstructure and magnetic properties have been studied by x-ray diffraction(XRD), atomic force microscopy (AFH), scanning electron microscope(SEM:), x-ray photoelectron spectroscopy(XPS), and conversion electron $M\"{o}ssbauer$ spectroscopy(CEMS). From the analysis of the x-ray diffraction patterns, the crystal structure for all films was found to be a hexagonal($P6_3cm$), which was preferentially grown along(110) direction. The lattice constant $c_0$ of the film with x=0.05 was close to that of single crystal, whereas lattice constant $a_0$ with respect to single crystal shows a slight decrease. This difference of lattice parameters between film and single crystal was caused by the lattice mismatch between the film and $Pt/Ti/SiO_2/Si$ substrate. Conversion electron $M\"{o}ssbauer$ spectrum of $HoMn_{0.95}Fe_{0.05}O_3$ thin film shows an asymmetry doublet absorption ratio at room temperature, which is due to the oriented direction of crystallographic domains. This is corresponding with analysis of x-ray diffraction. The quadrupole splitting(${\Delta}E_Q$) at room temperature is found to be $1.62{\pm}0.01mm/s$. This large ${\Delta}E_Q$ was caused by asymmetry environment surrounding Fe ion.

• (The)Study of the Eastern Classic
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• no.37
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• pp.127-159
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• 2009

This paper is about the conception of "Hwangjoin(皇朝人)" during the reign of King Youngjo in the Joseon Dynasity. Originally, Hwangjoin meant the Chinese people till the mid-term of the Joseon Dynasty but the meaning was changed to the immigrants from the Ming(明) dynasty in reign of King Youngjo. They were Han Chinese(漢族) and moved to the Joseon between the Japanese Invasion in 1592 and the Manchu war in 1636. The Joseon government gave a warm welcome to them. Two wars made the Joseon government pay attention to the national restoration and served the entrance of 'Sallim(山林)' on the central government as a momentum. Song, Siyeol(宋時烈) was the leader of Sallim, who made an issue of 'Daecheong-boksu Discourse(對淸復讐論;to revenge on Ching(淸) Dynasty)' like a way of 'Bukbeol(北伐;to attack Ching Dynasty)'. His plan came to fail because of the death of King Hyojong and was replaced with Jonju Discourse(尊周論;respect for Zhou Dynasty). Daebodan(大報壇) was built in the reign of King Sukjong, which meant Joseon got the justness that they inherited from the Ming Dynasty. Later Daebodan expanded and it led to works in honor of loyal subjects and patriots, victims of two wars and a policy of a warm reception for Hwangjoin. King Youngjo did his best to theorize Daemyeong Euiri Discourse(對明義理論) and Jonju Discourse for himself. His efforts came out as a spread of conception on Pungcheon(風泉;fengquan), publication and education of Eoje-seo (御製書) and making literary works(英祖御製). King Youngjo employed many policies for Hwangjoin. First, operation of Chungnyanggwa(忠良科) opened a door for them to go into politics. Second, descendants of Hwangjoin had charge of Hwangdan's guard(皇壇 守直) posts. and joined in the sacrificial rites of Ming Emperors. Third, they could have government jobs and honorary posts for ancestors' merits. Fourth, a list of Hwangjoin, "Hwainlok(華人錄)" was published and they got preferential treatment unlike Hyanhwain(向化人). King Young's Pungcheon(風泉) had an effect on literature such as Lee, Gyusang(李奎象)'s "Beong-sejaeunlok(幷世才彦錄)" and Song, Gyubin(宋奎斌)'s Pungcheon-yuhyang(風泉遺響)". The general people of Joseon were jealous and envious of them because of special treatment polices for Hwangjoin. So people wanted to be included in Hwangjoin as far as possible and there were cases of pretending to be a Hwangjoin. The conception of "Hwangjoin(皇朝人)" during the reign of King Youngjo was realized as the policy for Hwangjoin based on Daemyeong Euiri Discourse (對明義理論) and Jonju Discourse(尊周論). It was a way of becoming clear about Joseon's position in political principle.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.2
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• pp.27-41
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• 2014

This study aims to investigate the history, cultural values prototype through literature analysis, characteristics of construction, location, space structure and landscape characteristics by Arc-GIS on the Munam pavilion(聞巖亭) in Changnyeong. The results were as follows. First, Shin-cho((辛礎, 1549~1618) is the builder of the Munam pavilion and builder's view of nature is to go back to nature. The period of formation of Munam pavilion is between 1608-1618 as referred from document of retire from politics and build a pavilion. Secondly, Munam pavilion is surrounded by mountains and located at the top of steep slope. Pavilion was known as scenic site of the area. But damaged in a past landscape is caused by near the bridge, agricultural facilities, town, the Kye-sung stream of masonry and beams. Thirdly, Munam pavilion is divided into the main space, which is located on the pavilion, space in located on the pavilion east and west and the orient space, which is located on the Youngjeonggak. Of these, original form of Munam pavilion is a simple structure composed of pavilion and Munam rock, thus at the time of the composition seems to be a direct entry is possible, unlike the current entrance. Fourth, Spatial composition of Munam pavilion is divided into vegetation such as Lagerstroemia indica trees in Sa-ri in Changnyeong, ornament such as letters carved on the rocks and pavilion containing structure. The vegetation around the building is classified as precincts and outside of the premises. Planting of precincts was limited. Outside of area consists of front on the pavilion, which is covered with Lagerstroemia Indica forest and Pinus densiflora forest at the back of the pavilion. Ofthese,LargeLagerstroemiaIndicaforestcorrespondstothenaturalheritageasHistoricalrecordsofrarespeciesresourcesthatareassociated withbuilder. Letterscarvedontherocksrepresenttheboundaryof space, which is close to the location of the Munam pavilion and those associated with the builder as ornaments. Letters carved on the rocks front on the pavilion are rare cases that are made sequentially with a constant direction and rules as act of record for families to honor the achievements. Fifth, 'The eight famous spots of Munam' is divided into landscape elements that have nothing to do with bearing 4 places and landscape elements that have to do with bearing 4 places. Unrelated bearings of landscape elements are Lagerstroemia indica trees in Sa-ri in Changnyeong, Pinus densiflora forest at the back of the pavilion, Okcheon valley, Gwanryongsa temple and Daeheungsa temple. Bearing that related element of absolute orientation, which is corresponding to the elements are Daeheungsa temple, Hwawangsan mountain, Kye-sung stream and Yeongchwisan mountain. Relative bearing is Gwanryongsa temple, Yeongchwisan mountain and Kye-sung stream Gongjigi hill. At Lagerstroemia indica trees in Sa-ri in Changnyeong, Pinus densiflora forest at the back of the pavilion, Kye-sung stream and Okcheon valley, elements are exsting. Currently, it is difficult to confirm the rest of the landscape elements. Because, it is a generic element that reliable estimate of the target and locations are impossible for element. Munam pavilion is made for turn to nature by Shin-cho(辛礎). That was remained a record such as Munamzip(聞巖集) and Munamchungueirok(聞巖忠義錄) that is relating to construction of pavilion. Munam pavilion located in a unique form, archival culture through the letters carved on the rocks and Large Lagerstroemia indica forest and through eight famous spots, cultural landscape elements can be assumed that those elements are remained.