• 한국전기전자재료학회논문지
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• 제11권9호
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• pp.711-717
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• 1998

BST(70/30) and BST(50/50) thin films were prepared by Sol-Gel method and studied about the microstructural and dielectric properties with Pt and ITO bottom electrodes. The stock solution was synthesized and spin coated on the Pt/Ti$SiO_2$/Si and Indium Tin Oxide(ITO)/ glass substrate. the coated films were dries at 350$^{\circ}C$ for 10 minutes and annealed at $750^{\circ}C$ for 1 hour for the crystallization. The thin films coated on ITO substrate were crystallized easily and the packing density and roughness of surface were better that those of films coated on Pt substrates. In the BST(50/50) composition the structural properties were similar to the BST(70/30) composition and grain size were decreased with increasing the contents of Sr. The dielectric constant was higher in the BST(50/50) composition compared with the BST(70/30) composition. Using the ITO substrate, the dielectric constant was higher than the Pt substrate while the dielectric loss was showed a reverse trend. The dielectric constant with and increase of temperature was decreased slowly.

• 한국공간구조학회논문집
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• 제6권3호
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• pp.111-121
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• 2006

들림형 보구조는 휨재와 뜬지주, 스트링으로 조합되는 구조로서, 스트링에 PS력을 도입하여 휨재의 응력과 변형을 조절함으로써 구조능력을 높이는 구조시스템이다. 기존의 연구결과와 실사례를 조사하여 들림형 보구조의 특성과 구조계획시 구성방식을 파악하였다. 그 결과, 연력도형의 보의 형상 및 높낮이 그리고 스트링의 sag설정, 평면배열, 뜬지주의 수와 구성이 설계인자로서 고려될 수 있음을 파악하였고, 실사례와 구조적 거동의 연구고찰을 통해 그 설계인자의 세부 구성방식을 나타내었다. 또한 들림형 보구조는 큰 부가하중이 작용할 때의 구조부담을 줄이기 위하여 부가하중에 대해 별도의 저항 메카니즘을 고안함으로써 구조효율을 높일 수 있는 방식이 고려될 수 있음을 보였다.

• 한국전기전자재료학회논문지
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• 제16권4호
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• pp.317-321
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• 2003

In this study, the structural properties were Investigated for the deposited (Ba,Sr)(Nb,Ti)O$_3$[BSNT] thin films grown on Pt/TiO$_2$/SiO$_2$/Si substrate by RF sputtering method. The structural properties of the BSNT thin films affected by the Ar/02 ratios were Investigated. In the case of the BSNT thin films deposited with condition of 60/40(Ar/O$_2$) ratio, the BaTiO$_3$, SrTiO$_3$ and BaNbO$_3$ phases were showed. The composition ratio of Nb and Ti in the BSNT thin films were nearly equivalent. Also, in the BSNT thin films deposited with condition of 60/40 and 80/20(Ar/O$_2$) ratios, the composition of Ba, Sr, Nb and Ti were relatively uniform. The Ba, Sr, Nb and Ti in the BSTN thin films were not diffused into the Pt layer.

• 한국디지털건축인테리어학회논문집
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• 제10권1호
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• pp.49-56
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• 2010

The purpose of this study is to examine the relationship between the structural system used in modern architecture and the form and spatial composition of the buildings. The principle in stabilization of structures is closely related to the architectural form. That is, in order to stabilize a building, a special type of structural system is required and consequently shows up with consistent characteristics in the architectural form. Modern architecture can be classified into skeleton structure, trusses structure, and space structure according to the structural characteristics. Skeleton structure is then divided into a perpendicular form and tapered form. Trusses structure is categorized as dome-shaped structure and slab-shaped structure, and space structure can be divided into compressible space structure and tensile space structure. When classifies the modern building with the aspect of architectural effect, there is a possibility of trying to divide with effect of production, and its expression. Effect of production mean structural system and effect of expression mean space and plan.

• 한국구조물진단유지관리공학회 논문집
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• 제12권3호
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• pp.155-166
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• 2008

연구대상댐의 우안부는 콘크리트구조물로 축조된 콘크리트 중력식댐으로 이루어져 있고, 좌안부는 사력재료로 이루어진 사력댐으로 구성되어 있는 복합댐이다. 이련 형식의 댐 거동에 대한 연구에 있어서 국내는 물론 선진외국의 참고자료도 희소한 실정이다. 국내의 경우 약 17,000의 저수시설물중 복합댐 형식은 지자체나 기타 기관에서 관리하는 생 공 용수댐의 경우 거의 존재하지 않으며, 설혹 존재하더라도 시설물의 관리자료가 전무한 실정으로, 국내 다목적댐 중 유일한 복합댐을 선정하여 중력식댐과 사력댐 접합부의 거동특성을 분석하였다. 본 연구에서는 해석적 방법에 의하여 복합댐의 동적 상호거동특성을 분석하기 위하여 댐 축을 기준으로 모델링하여 정적(유사정적법, 수정진도법) 및 동적해석을 수행하여, 지진시 콘크리트댐과 사력댐 접합부의 지진 응답해석을 분석하였다.

• 한국재료학회지
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• 제12권11호
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• pp.875-879
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• 2002

$Pb_{1-x}$ $Cd_{x}$ $I_2$ (x=0.0, 0.2, 0.5, 0.7, 0.9, 1.0) single crystals were grown by using Bridgman method and their structural and optical properties were investigated from the measurement of X-ray diffraction, optical absorption and photoluminescence. As-grown single crystals have hexagonal closed packed layered structure. The values of lattice constant c decrease with increasing composition x. Direct and indirect transition optical energy band gaps are calculated from optical absorption spectra measured at room temperature. They increase exponentially from 2.3eV to 3.2 eV with increasing composition x. The energies of photoluminescence peak due to donor bound exciton measured at 6K increase with increasing composition . However, the peak energies of donor-acceptor pair (DAP) are independent of the optical energy band gaps of $Pb_{1-x}$/$Cd_{x}$ $I_2$ single crystals.

• 한국전기전자재료학회논문지
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• 제13권1호
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• pp.66-74
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• 2000

The structural and electrical characteristics of SBT thin films, fabricated on Pt/Ti/SiO\ulcorner/Si substrates by a pulsed laser deposition(PLD), were investigated to develop ferroelectric thin films for capacitor lay-ers of FRAM. EFfects of target composition on the characteristics of SBT thin films were examined. Target were prepared by mixed oxide method, and composition of Sr/Bi/Ta on SBT was changed to 1/2/2, 1/2.4/2, 1/2.8/2, 0.8/2/2 and 1.2/2/2. SBt thin films were fabricated, as a function of substrate temperature and oxygen pressure, by PLD. The optimized ocndition, to fabricate high quality SBT thin films, was 700 $^{\circ}C$ of substrate temperature, 200 mTorr of oxygen pressure, and 2 J/$\textrm{cm}^2$ of laser energy density. Maximum remnant value(2Pr) of 9.0 $\mu$C/$\textrm{cm}^2$, coercive field value(Ec) of 50 kV/cm, dielectric constant value of 166, and leakage current densities of <10\ulcorner A/$\textrm{cm}^2$ were observed for the films with 1/2/2 composition, which was prepared at the above PLD condition.

• 한국세라믹학회지
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• 제50권4호
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• pp.288-293
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• 2013

Zn-In-Sn-O films were prepared at room temperature by combinatorial RF-magnetron co-sputtering system. The cationic contents of the films were varied using a compositionally combinatorial technique. The effects of the oxygen partial pressure and film compositionon the structural and electrical properties were investigated. The Zn-In-Sn-O films deposited at Ar gas atmosphere showed an amorphous phaseirrespective of the film composition. However, the amorphous Zn-In-Sn-O films with a Zn content below 30.0 at% were converted into a bixbyite type-ITO polycrystalline phase with an increase in the oxygen partial pressure. The resistivity, carrier concentration, and Hall mobility were strongly affected by the oxygen partial pressure and chemical composition of the film. At sufficiently high carrier densities above $5{\times}10^{18}cm^{-3}$, the conduction behavior of amorphous Zn-In-Sn-O film changes from thermally activated to degenerate band conduction accompanied with high mobility.

• KSBB Journal
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• 제24권6호
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• pp.584-590
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• 2009

A hot-water extract from fruit body of Auricularia auricula was purified by ethanol precipitation and subsequent dialysis. The polysaccharide showed a typical IR spectrum similar to $\beta$-glucan and was composed of glucose and mannose in a molar ratio of 16.8:83.2 indicating that it is a glucomannan. A glucomannan-like polysaccharide was also identified from Tremella fuciformis. Both of the polysaccahrides showed the presence of acetyl groups and presented colorimetric responses for $\beta$-1,4-glucomannan indicating the acetylated $\beta$-glucomannan similar to the typical polysaccharide found in Aloes.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.545-548
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• 2002

$(Ba_{0.6-x}Sr_{0.4}Ca_x)TiO_3$(BSCT) (x=0.10, 0.15, 0.20) powders were prepared by the sol-gel method and BSCT thick films were fabricated by the screen-printing method. The structural properties as a faction of the composition ratio were studied. As a result of the differential thermal analysis (DTA), exothermic perk was observed at around $860^{\circ}C$ dne to the formation of the polycrystalline perovskite phase. The BSCT thick films sintered at $1350^{\circ}C$ for 2h showed the average grain size of $2{\sim}7{\mu}m$. The average thickness of BSCT thick films, obtained by 3 times of screen-printing, was approximately $85{\mu}m$.