• 한국전기전자재료학회논문지
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• 제23권12호
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• pp.988-995
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• 2010

In this study the (Alnico, Sm-Co) bonded magnets were fabricated by mixing the Sm-Co added alnico alloy powders with epoxy resin and binder, appropriately. Also, the hybrid ring magnets of (Alnico, Sm-Co)/Sr-ferrite were fabricated by coupling the Sr-ferrite composite layer with an (Alnico, Sm-Co) magnet. The magnetic properties of (Alnico, Sm-Co) ring magnets were varied with the amount of Sm-Co powders. The addition of Sm-Co powders increased a remanent induction($B_r$) and coercive force($_BH_C$), while decreasing a surface flux density and repulsive distance. The surface flux density and repulsive distance for the (Alnico, Sm-Co) ring magnet increased with a magnetizing voltage up to about 160 V and reached an apparent saturation point. Also, the measurements of temperature and moisture characteristics showed that the surface flux densities of N-S poles and repulsive distance decreased a little within 4% after 10 days passed.

• 한국분말재료학회지
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• 제20권1호
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• pp.13-18
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• 2013

In the present study, we systematically investigated the effect of Mn addition on nitrogenation behavior and magnetic properties of Sm-Fe powders produced by reduction-diffusion process. Alloy powders with only $Sm_2(Fe,Mn)_{17}$ single phase were successfully produced by the reduction-diffusion process. The coercivity of $Sm_2(Fe,Mn)_{17}$ powder rapidly increased during nitrogenation and reached the maximum of 637 Oe after 16 hours. After further nitrogenation, it decreased. In contrast, the coercivity of $Sm_2Fe_{17}$ powder gradually increased during nitrogenation for 24 hours. The coercivity of $Sm_2(Fe,Mn)_{17}$ powder was higher than that of $Sm_2Fe_{17}$ powder at the same condition of nitrogenation. It was considered that the Mn addition facilitates the nitrogenation of $Sm_2Fe_{17}$ powder and enhances the coercivity.

• Progress in Superconductivity
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• 제11권2호
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• pp.141-146
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• 2010

Phase stability diagram and boundary of a- and c-axis orientation of $SmBa_2Cu_3O_{7-y}$ (SmBCO) thin films grown by pulsed laser deposition (PLD) were reported with studies based on x-ray diffraction [1]. Four different samples are systematically analyzed: normal c-axis oriented orthorhombic $SmBa_2Cu_3O_{7-y}$, a-axis oriented $SmBa_2Cu_3O_{7-y}$, c-axis oriented orthorhombic $SmBa_2Cu_3O_{7-y}$ with $Sm_2BaCuO_5$ phase, and a mixture with c-axis oriented orthorhombic $SmBa_2Cu_3O_{7-y}$ and anomalously long-c tetragonal $SmBa_2Cu_3O_x$. Raman scattering spectroscopy equipped with polarization analysis elucidates the crystal orientation and the origin of the growth of the materials. It indicates that the technique can be used for quality control of conductor manufacturing processes as well as for enhancement of the materials properties.

• 한국전기전자재료학회논문지
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• 제16권4호
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• pp.336-342
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• 2003

(Sm/Y)$_{1.8}$B $a_{2.4}$C $u_{3.4}$$O_{7-x}$ [(Sm/Y)1.8] high $T_{c}$ superconductors were directionally grown by Rod-type Seed Melt Growth(RSMG) process in air atmosphere. The sintered polycrystalline N $d_{1.8}$B $a_{2.4}$C $u_{3.4}$$O_{7-x}$(Nd1.8) of rod-type seed crystal grown by extrusion mold process were used for achieving the ab-plane alignment haying large grains perpendicular to the center of (Sm/Y)1.8 samples. The observations using TEM micrographs of the melt-textured (Sm/Y)1.8 samples revealed that the nonsuperconducting (Sm/Y)211 inclusions are uniformly distributed in the superconducting (Sm/Y)123 matrix. The microstructure and superconducting properties were investigated by XRD, TEM and SQUID magnetometer. The RSMG (Sm/Y)1.8 samples showed an onset $T_{c}$ $\geq$ 90 K and sharp superconducting transition.nsition.ion.nsition.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 센서 박막재료 반도체 세라믹
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• pp.190-193
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• 2003

Sm-doped lead zirconate titanate($Pb_{1.1}(Zr_{0.6}Ti_{0.4})O_3$; PZT) thin films on the Pt(111)/Ti/$SiO_2$/Si(100) substrates prepared by a sol-gel method. The effect on structural and electrical properties of PZT thin films measured according to the Sm content. Sm-doping altered significantly dielectric and ferroelectric properties. The remanent polarization and the coercive field decreased with the increasing Sm content. The dielectric constant and the dielectric loss of PZT thin films decreased with the increasing Sm content. At 100 kHz, the dielectric constant and the dielectric loss of. the 0.3 mol% of Sm-doped PZT thin film were 1200 and 0.12 respectively. The remanent polarization (2Pr) of the 0.3 mol% of Sm-doped PZT thin film was $52.13{\mu}C/cm^2$ and the coercive field was 94.01 kV/cm. The 0.3 mol% of Sm-doped PZT thin film showed an improved fatigue characteristic comparing to the undoped PZT thin film.

• 대한한방부인과학회지
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• 제24권2호
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• pp.33-51
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• 2011

Objectives: This study was performed to assess the protective effect of Saengmaek-san (SM) on UVB-induced HaCaT cell damage. Methods: The protective effects of Saengmaek-san(SM) were determined by UVB-induced HaCaT assay. We assessed protective effects of Saengmaek-san (SM) on LDH release and nitrite release from HaCaT. And COX-2, Bcl-2, Bax, $TNF{\alpha}$, c-jun, c-fos, NF-kB, iNOS, Bcl-xL gene expression were determined in HaCaT using real-time PCR method. Results: 1. SM inhibited LDH-release, nitrite production in UVB-exposed HaCaT. 2. SM suppressed the gene expression of COX-2, $TNF{\alpha}$ in UVB-exposed HaCaT. 3. SM increased the gene expression of Bcl-2, Bax, Bcl-xL family protein in UVB-exposed HaCaT. 4. SM suppressed the gene expression of c-jun, c-fos, NF-kB in UVB-exposed HaCaT. Conclusions: The study showed SM inhibited the cell damage in UVB-exposed HaCaT.

• 한국자기학회지
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• 제5권5호
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• pp.726-729
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• 1995

We investigated the effects of Sm on the microstructure and magnetic properties of Fe-Co Alloy films prepared by a DC triode sputtering. The magnetostriction was found to be changed with the Sm content from positive to negative values, taking a zero magnetostriction was at about 3 at% Sm. The Sm content dependence of magnetostriction was explained by the formation of Sm enriched amorphous phase surrounding the main bcc (Fe,Co) crystalline phase, which was observed by a high resolution transmission electron microscopy.

• 대한수학회보
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• 제52권4호
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• pp.1285-1295
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• 2015

An SM domain is an integral domain which satisfies the ascending chain condition on w-ideals. Then an SM domain also satisfies the descending chain condition on those chains of v-ideals whose intersection is not zero. In this paper, a study is begun to extend these properties to commutative rings with zero divisors. A $Q_0$-SM ring is defined to be a ring which satisfies the ascending chain condition on semiregular w-ideals and satisfies the descending chain condition on those chains of semiregular v-ideals whose intersection is semiregular. In this paper, some properties of $Q_0$-SM rings are discussed and examples are provided to show the difference between $Q_0$-SM rings and SM rings and the difference between $Q_0$-SM rings and $Q_0$-Mori rings.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.193-197
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• 2004

The effect of the temperature dependence of the smectic layer spacing in the smectic-A (SmA) phase on the formation of defects in the ferroelectric smectic-$C^{\ast}$ ($SmC^{\ast}$) phase is investigated with x-ray scattering technique. The study is based on thin parallel-aligned surface stabilized ferroelectric liquid crystal cells with two different alignment conditions, high pretilt $SiO_x$, alignment and low pretilt polyimide films. It is found that defects observed in the $SmC^{\ast}$ phase have much more profound dependence on the layer changes and chevron formation in the SmA phase than in the $SmC^{\ast}$ phase. We find that thermal layer expansion with decreasing temperature in the SmA phase suppresses the formation of defects observed in the SmC phase.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2014년도 하계학술대회
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• pp.64-66
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• 2014

본 논문에서는 케이블 TV 콘텐트를 대용량의 Wi-Fi 통신을 이용하여 전송하고, 집 안에 배치된 여러 가지의 수신기를 이용하여 콘텐트를 편하게 즐길 수 있는 서비스에 적합한 SM(spatial modulation) 전송기법의 수신 성능을 분석한다. 케이블 채널의 개수는 100가지가 넘으며 HD 이상의 화질을 가진다. 이러한 수십 개의 대용량 콘텐트를 무선으로 한정된 대역폭에 전송하기 위해서는 공간다중화 방식의 MIMO 기법이 필요하다. 그 중에서도 채널 간의 간섭이 많은 집 안 환경에 적합한 SM 전송기법은 수신 신호간의 간섭이 없으며 수신기가 간단하다는 장점을 가지고 있다. 또한 기존 SM의 낮은 대역효율을 증가시키기 위한 golden-SM 방식도 제안되었다. 그러나 실제 채널 환경에서의 기존 SM 전송기법들의 수신 성능은 비교된 것이 거의 없으므로 본 논문에서는 WiMAX(IEEE802.16a)에서 사용되고 있는 SUI 채널 모델을 고려하여 기존 SM 기법들의 수신 성능을 비교분석하였다.