• Title/Summary/Keyword: BCC-O

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Improving Outcome of Mass Media (매스미디어 운영에 따른 성과제고에 관한 연구 -국내 신문산업을 중심으로-)

  • Hwang, Jong-Ho
    • The Journal of the Korea Contents Association
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    • v.13 no.1
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    • pp.366-375
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    • 2013
  • Recently, management of Newspaper developmet of the internet news, broadcasting and free newspapers escalated competition between newspaper companies and other media companies as well as competition among newapaper companies. This paper analyzes the efficiency of Korean Newapaper using DEA model. We evaluate the CCR-O, BCC-O efficiency, SE and RTS of 30 Newspaper. We also suggest the Newpaper which can be benchmarked based on analyzed information. The result shows that ten Nespaper whose values of CCR-O efficiency are 1, and Fourteen Nespaper whose values of BCC efficiency are 1. RTS indicates IRS of 1 firms, DRS of 16 firms and CRS of 13 firms. To variables on the effectiveness of newspaper publishing companies for the understanding and performance analysis.

Protective Effects of BCC Against Oxidative Stress in Cardiomyocyte Cells

  • Bong-Geun Shin;Dae-Kwan Kim
    • Biomedical Science Letters
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    • v.30 no.1
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    • pp.10-16
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    • 2024
  • Oxidative stress caused by elevated reactive oxygen species (ROS) in the heart causes various heart diseases. Oxidative stress is known as a factor that causes diseases in various organs as well as the heart. Diseases such as heart failure, myocardial infarction, and cardiomyopathy caused by oxidative stress in the heart can be treated with medication or surgery. Recently, blood cells concentrate (BCC) is used in various treatment areas such as orthopedics, gynecology, and urology. BCC therapy is applied to treatment by concentrating platelets and white blood cells necessary for regeneration through simple centrifugation using autologous blood. As the platelets are activated, many growth factors are released from alpha granules of the platelets. Growth factors such as TGF-β1, PDGF, VEGF, and EGF derived from platelets are involved in various cell signaling pathway. Due to these growth factors, BCC can contribute to tissue regeneration and can treat various diseases. CD34+ cells contained in BCC may also play an important role in tissue regeneration. In this study, we investigated whether BCC has a regenerative effect on heart disease, and if so, what mechanism causes the effect. To observe this, cardiomyocyte cells were treated with H2O2 to induce oxidative stress. And the effect was confirmed in the presence or absence of BCC. As a result, in the presence of BCC, the oxidative stress of cardiomyocyte cells was reduced and cell damage was also reduced. These results suggest that BCC therapy can be a new treatment alternative for heart disease.

Amorphous Cr-Ti Texture-inducing Layer Underlying (002) Textured bcc-Cr alloy Seed Layer for FePt-C Based Heat-assisted Magnetic Recording Media

  • Jeon, Seong-Jae;Hinata, Shintaro;Saito, Shin
    • Journal of Magnetics
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    • v.21 no.1
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    • pp.35-39
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    • 2016
  • $Cr_{100-x}Ti_x$ amorphous texture-inducing layers (TIL) were investigated to realize highly (002) oriented $L1_0$ FePt-C granular films through hetero-epitaxial growth on the (002) textured bcc-$Cr_{80}Mn_{20}$ seed layer (bcc-SL). As-deposited TILs showed the amorphous phase in Ti content of $30{\leq}x(at%){\leq}75$. Particularly, films with $40{\leq}x{\leq}60$ kept the amorphous phase against the heat treatment over $600^{\circ}C$. It was found that preference of the crystallographic texture for bcc-SLs is directly affected by the structural phase of TILs. (002) crystallographic texture was realized in bcc-SLs deposited on the amorphous TILs ($40{\leq}x{\leq}70$), whereas (110) texture was formed in bcc-SLs overlying on crystalline TILs (x < 30 and x > 70). Correlation between the angular distribution of (002) crystal orientation of bcc-SL evaluated by full width at half maximum of (002) diffraction (FWHM) and a grain diameter of bcc-SL indicated that while the development of the lateral growth for bcc-SL grain reduces FWHM, crystallization of amorphous TILs hinders FWHM. $L1_0$ FePt-C granular films were fabricated under the substrate heating process over $600^{\circ}C$ with having different FWHM of bcc-SL. Hysteresis loops showed that squareness ($M_r/M_s$) of the films increased from 0.87 to 0.95 when FWHM of bcc-SL decreased from $13.7^{\circ}$ to $3.8^{\circ}$. It is suggested that the reduction of (002) FWHM affects to the overlying MgO film as well as FePt-C granular film by means of the hetero-epitaxial growth.

An Analysis of Efficiency of Superior Appraisal Corporations Using DEA (DEA 모형을 이용한 우수감정평가법인의 효율성 분석)

  • Lee, Chan-Ho;Kim, Jong-Ki;Hwang, Soo-Jin;Jeon, Jin-Whan
    • The Journal of the Korea Contents Association
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    • v.10 no.12
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    • pp.290-299
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    • 2010
  • This study aims to evaluate the efficiency of superior appraisal corporations using DEA(Data Envelopment Analysis). DEA is known as a method for evaluating relative efficiency of organizations with multiple inputs and outputs. We used CCR-O and BCC-O DEA models to evaluate relative efficiency of superior appraisal corporations. Input variable is number of appraisers, output variables are total sales and net income. Total of 13 appraisal corporations in Korea were selected for this study, and the data were collected from financial reports for 2008 fiscal year. The result of this study is summarized as follows. First, the average of superior appraisal corporation's technical efficiency score is about 88.3% by applying CCR-O model. Second, the average of superior appraisal corporation's pure technical efficiency score is about 90% and scale efficiency score is about 98.2% by applying BCC-O model. According to the result of DEA, the cause of inefficiency is pure technical efficiency.

Phase transformation and magnetic properties of NiFe thin films on Si(100) wafer and SiO2/Si(100) substrate by co-sputtering (Si(100) wafer와 SiO2/Si(100) 기판에 동시 스퍼터링법으로 증착된 NiFe 합금 박막의 상변화 및 자기적 특성)

  • Kang, Dae-Sik;Song, Jong-Han;Nam, Joong-Hee;Cho, Jeong-Ho;Chun, Myoung-Pyo
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.20 no.5
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    • pp.216-220
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    • 2010
  • Ni-Fe alloys have various applications such as thin film inductor, thin film transformer, magnetic head's shield case, etc. Magnetic properties of Ni-Fe thin films depend on the process parameters such as thickness, contents, deposition rate, substrates, etc. In this study, NiFe films with a thickness of about 150nm were deposited on Si(100) wafer and $SiO_2$/Si(100) substrate at room temperature by a DC magnetron co-sputtering using Fe and Ni targets. Their phase formation and magnetic properties as a function of annealing temperature were investigated with XRD, FE-SEM and VSM. The assputtered films have BCC structure. With increasing annealing temperature, NiFe thin film for $SiO_2$/Si(100) substrate transformed completely from BCC to FCC phase above $500^{\circ}C$, but some BCC phase remained above $500^{\circ}C$ on Si(100) wafer. For samples annealed at $450^{\circ}C$, squareness ratio of NiFe thin film shows peak value and its saturation magnetization is around 0.0118 emu, which means that the optimum annealing temperature of NiFe thin film seems to be $450^{\circ}C$. The saturation magnetization of films decreased rapidly above the annealing temperature of $500^{\circ}C$ due to phase transformation from BCC to FCC phase.

The Influence of Powder Size on Mechanical Properties of Small MIM Parts

  • Yasui, Noriyuki;Satomi, Hiroshi;Fujiwara, Hiroshi;Ameyama, Kei;Kankawa, Yoshimitsu
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09a
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    • pp.39-40
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    • 2006
  • The relationship between the powder particle size change and a mechanical property of the Metal Injection Molding (MIM) product was examined in detail. The XRD results indicate that the diffraction peaks of BCC appeared in compacts of powder particle size of 4 to $10{\mu}m$ as well as the bulk SUS630. However, the diffraction peaks from both BCC and FCC were observed in the compact with powder size less than $3{\mu}m$. TEM observation revealed that the powder with those BCC/FCC two phase structure have a finely dispersed $SiO_2$ precipitates. Because the Si is ferrite stabilizing element, decrease of Si composition in the matrix phase by the $SiO_2$ precipitation resulted in formation of the retained austenite. Therefore, controlling the elements such as Si as well as oxygen decrease is very important to obtain a normal microstructure in ultra-fine powder $(<3{\mu}m)$ injection molding.

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A Study on Embrittlement of Fast Neutron-irradiated Nuclear Reactor Pressure Vessel Steels at Room- and Liquid Nitrogen-temperature (상온 및 액체질소 온도에서 고속 중성자 조사된 원자로 압력 용기의 취화 현상에 관한 연구)

  • Kim, H.B.;Kim, H.S.;Kim, S.K.;Shin, D.H.;Yu, Y.B.;Ko, J.D.
    • Journal of the Korean Magnetics Society
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    • v.15 no.2
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    • pp.142-147
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    • 2005
  • The embrittlement of fast neutron-irradiated reactor pressure vessel (RPV) steels was investigated by X-ray diffraction patterns at room temperature and $M\ddot{o}ssbauer$ spectroscopy at room- and liquid nitrogen-temperature. Neutron fluence on the samples were $10^{12},\;10^{13},\;10^{14},\;10^{15},\;10^{16},\;10^{17},\;10^{18}\;n/cm^2$. The X-ray diffraction patterns showed that the structure of the neutron unirradiated sample was bcc type, where as but the neutron irradiated samples with the fluence higher than $10^{17}\;n/{\cal}cm^2$ were so severely damaged, that bcc type structure disappeared. The $M\ddot{o}ssbauer$ spectra of all samples showed superposition of two or more sextets. In this paper all $M\ddot{o}ssbauer$ spectra were fitted by three set of sextet. The isomer shift and quadrupole splitting values were found around zero. At liquid nitrogen temperature, magnetic hyperfine field and absorption area increase rapidly S 1 sextet in the samples of $10^{17}\~10^{18}\;n/{\cal}cm^2$ neutron fluences. And at room temperature, magnetic hyperfine field and absorption increased rapidly at SI sextet in the samples of $10^{17}\~10^{18}\;n/{\cal}cm^2$ neutron fluences. This rapid increase of magnetic hyperfine field and absorption area were inferred to be caused by the change of $^{56}Fe,\;^{55}Mn$ into $^{57}Fe$ due to by neutron irradiation.

Magneto-optical and optical properties of Fe-Au alloy films in a wide composition range

  • Hyun, Y.H.;Kim, C.O.;Lee, Y.P.;Kudryavtsev, Y.V.;Gontarz, R.;Kim, K.W.
    • Journal of Korean Vacuum Science & Technology
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    • v.5 no.2
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    • pp.43-46
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    • 2001
  • Fe-Au alloys are characterized by the complete solubility, and exhibit an fcc-bcc structural transformation at the Fe-rich side. The magneto-optical(equatorial Ken effect : EKE) and optical properties of Fe$\_$1-x/Aux (0 < x < 1) were investigated in the 0.5 - 5.0 eV energy range. The x-ray diffraction study shows the structural fcc-bcc transformation about 80 at. % of Fe. Noticeable changes in the optical properties caused by the fcc-bcc structural transformation was observed. The shape and intensity of the EKE spectra as well as the field dependence of the magneto-optical response were also significantly changed. It is thought that these changes are mainly comes from the induced magnetic moment in Au(and/or the emhanced magnetic moment of Fe). The nature of the prominent structure observed in the UV range of the magneto-optical Ken effect of Au/Fe multilayered films are disscussed in connection with the above results.

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Crystallization and Magnetic Properties of Non-Equilibrium Al(Fe-Cu) Alloy Powders Produced by Rod Milling and Chemical Leaching (Rod Milling과 Chemical Leaching에 의해 제작된 비평형 Al(Fe-Cu) 합금 분말의 결정화 및 자기적 특성)

  • Kim Hyun-Goo
    • Journal of Powder Materials
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    • v.11 no.6 s.47
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    • pp.486-492
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    • 2004
  • We report the crystallization and magnetic properties of non-equilibrium $Al_{0.6}(Fe_{x}Cu_{1-x})_{0.4}(x=0.25, 0.50, 0.75)$ alloy powders produced by rod-milling as well as by new chemical leaching. X-ray diffractometry, transmission electron microscopy, differential scanning calorimetry and vibrating sample magnetometry were used to characterize the as-milled and leached specimens. After 400 h or 500 h milling, only the broad peaks of nano bcc crystalline phases were detected in the XRD patterns. The crystallite size, the peak and the crystallization temperatures increased with increasing Fe. After being annealed at $600{^\circ}C$ for 1 h for as-milled alloy powders, the peaks of bcc $AlCu_{4}\;and\;Al_{13}Cu_{4}Fe_{3}\;for\;x=0.25,\;bcc\;AlCu_{4}\;and\;Al_{5}Fe_{2}\;for\;x=0.50,\;and\;Al_{5}Fe_{2},\;and\;Al_{0.5}Fe_{0.5}\;for\;x=0.75$ are observed. After being annealed at $500{^\circ}\;and\;600{^\circ}C$for 1 h for leached specimens, these non-equi-librium phases transformed into fcc Cu and $CuFe_{2}O_{4}$phases for the x=0.25 specimen, and into bcc ${\alpha}-Fe,\;fcc\;Cu,\;and\;CuFe_{2}O_{4}$ phases for both the x=0.50 and the x=0.75 specimens. The saturation magnetization decreased with increasing milling time for $Al_{0.6}(Fe_{x}Cu_{1-x})_{0.4}$ alloy powders. On cooling the leached specimens from $800{\~}850^{\circ}C$,\;the magnetization first sharply increase at about $491.4{\circ}C,\;745{\circ}C,\;and\;750.0{\circ}C$ for x=0.25, x=0.50, and x=0.75 specimens, repectively.

Microstructural and Magnetic Properties of CoFeB/MgO/CoFeB Based Magnetic Tunnel Junction Depending on Capping Layer Materials (Capping층 재료에 따른 CoFeB/MgO/CoFeB 자기터널접합의 미세구조와 자기저항 특성)

  • Chung, Ha-Chang;Lee, Seong-Rae
    • Journal of the Korean Magnetics Society
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    • v.17 no.4
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    • pp.162-165
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    • 2007
  • We investigated the effects of the capping layer materials on the crystallization of the amorphous top-CoFeB (t-CoFeB) electrode and the magnetoresistance properties of the magnetic tunnel junctions (MTJs). When the hcp(002)-textured Ru capping layer was used, the amorphous t-CoFeB was crystallized to bcc-CoFe(110). The CoFe(110)/Ru(002) texture relation can be minimized the lattice mismatch down to 5.6%. However, when the fine polycrystalline but almost amorphous TiAl or amorphous ZrAl were used, the amorphous t-CoFeB was crystallized to bcc-CoFe(002). When the amorphous capping materials were used, the evolution of the t-CoFeB texture was affected mainly by the MgO(001) texture. Consequently, the M ratios of the annealed MTJ capped with the ZrAl and TiAl (72.7 and 71.8%) are relatively higher than that of the MTJ with Ru capping layer (46.7%). In conclusions, the texture evolution of the amorphous t-CoFeB during the post deposition annealing could be controlled by the crystallinity of the adjacent capping layer and in turn, it affects the TMR ratio of MTJs.