• 제목/요약/키워드: T. Saito

검색결과 44건 처리시간 0.026초

경유자동차 입자상물질의 휘발성에 대한 실험적 연구 (Experimental Study of Volatility of Diesel Exhaust Particles)

  • Gwon Sun-Park;Lee Gyu-Won;Saito K.;Shinozaki O.;Seto T.
    • 한국대기환경학회:학술대회논문집
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    • 한국대기환경학회 2002년도 춘계학술대회 논문집
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    • pp.229-230
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    • 2002
  • Diesel exhaust particles are mostly sub-micrometer agglomerates composed of carbonaceous primary particles ranging from 10 to 80nm, but contain also adsorbed or condensed hydrocarbons, hydrocarbon derivatives, sulfur compounds, and other materials. If particles are primarily composed of volatile materials, they have different health impacts from solid particles. Thus, the analysis of the volatility of diesel particles is one of an important diesel research area. (omitted)

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밀 단백 효소 가수분해물의 항균활성 (Antimicrobial Activity of Gluten Hydrolysate with Asp. saitoi Protease)

  • 이상덕;주정현;이규희;이기택;오만진
    • 한국식품영양과학회지
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    • 제32권5호
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    • pp.745-751
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    • 2003
  • 밀 단백질에 효소가수 분해할 때 생산되는 peptide의 항균활성과 천연항균제로서의 이용가능성을 검토하기 위하여 실험을 행하였다. 밀 단백질에 7종의 단백질가수분해효소를 작용시켜 생성된 가수분해물의 항균활성을 측정하고 한외여과, membrane filtration, HPLC를 이용하여 항균성 peptide를 분리 정제한 후 분자량과 아미노산 결합순서를 측정한 결과는 다음과 같다. 밀 단백질에 7종의 단백질 분해효소를 적용시켜 제조한 가수분해물중 Asp. saito protease를 적용시켜 얻어진 peptide만이 항균활성을 나타내었다. Asp. saito protease는 37$^{\circ}C$, pH 6.0에서 작용시킨 경우에 항균활성이 가장 높았으며, 5$0^{\circ}C$ 이상에서는 활성을 나타내지 않았다. 밀단백 효소가수분해물은 membrane filtration에 의하여 분자량 1,000~3,000에서 항균활성이 나타났다. Membrane filtration으로 얻어진 항균활성분획을 HPLC로 분리한 결과 retention time 31.1~31.8 min에서 항균활성을 나타내었다. 밀단백 효소가수분해물은 121$^{\circ}C$에서 15분간 가열하여도 효소활성이 유지되는 매우 안정한 화합물이었다. 항균활성분획을 MALDI-mass로 질량을 분석한 결과 1,633이었다. 항균성 peptide의 아미노산 결합순서는 cysteine, glycine, prolin, valine, valine, alanine, alanine, arginine의 순서였다.

Inter Landau Level Optical Absorption in Graphene Under Ultra-high Magnetic Field

  • Saito, H.;Nakamura, D.;Takeyama, S.;Kim, Yong-Min;An, K.S.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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    • pp.360-360
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    • 2012
  • Graphene shows diverse novel physical properties arising from its peculiar electronic states, so called Dirac electrons. Especially, effect of magnetic field is very unique, exhibiting exotic Landau level (LL) splitting. LLs are substantially modified by spins of Dirac electrons and pseudo-spins. The degeneracy of LLs is lifted to show splitting by electron-electron interaction and by the Zeeman effect. We investigated the magneto-optical absorption of graphene subjected to ultra-high magnetic field. Samples were prepared by the CVD method deposited on GaAs and Quart substrate. We have confirmed existence of graphene on each substrate by the micro-Raman spectroscopy. Next, we conducted magneto-absorption measurements in magnetic field up to 120 T by the single-turn coil (STC) method. We could observe absorption peak at 65 T and 100 T, respectively, probably arising from the LL inter-band transitions.

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Distalization with a modified C-palatal plate for severe upper crowding and a missing lower incisor

  • Park, Jae Hyun;Saito, Traci;Yoo, Sun Kyong;Alfaifi, Mohammed;Kook, Yoon-Ah
    • 대한치과교정학회지
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    • 제50권1호
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    • pp.52-62
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    • 2020
  • This case report presents the orthodontic treatment of a 25-year-old patient with skeletal Class II and severe maxillary arch crowding, moderate mandibular arch crowding, anterior crossbite, and a missing lower incisor. He was treated with molar distalization using a modified C-palatal plate and temporary anchorage devices to create sufficient space for retraction. The total treatment duration was 21 months. After treatment, his occlusion and smile esthetics showed significant improvement. The modified C-palatal plate represents a treatment modality that enhances the prospects of non-extraction treatment and reduces the need for extraction.

Immune activation and radioprotection by Echinacea purpurea (American herb)

  • Mishima, Satoshi;Gu, Yeun-Hwa;Saito, Kiyoto;Yamashita, Takenori;Maruyama, Hiroe;Inoue, Makoto;Ahn, Kyoo-Seok
    • Advances in Traditional Medicine
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    • 제4권3호
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    • pp.163-170
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    • 2004
  • The effect of immune activation by Echinacea purpurea was investigated by measuring total immunoglobulin (Ig) G, IgM. and the radioprotective effect of immune activation by Echinacea purpurea was investigated by measuring T lymphocyte subsets in the peripheral blood of mice following whole body irradiation. Echinacea purpurea activated macrophages to stimulate $IFN-{\gamma}$ production in association with the secondary activation of T lymphocytes, resulting in a decrease in IgG and IgM production. Cytokines released from macrophages in mouse peripheral blood after Echinacea purpurea administration activated helper T cells to proliferate. In addition, activated macrophages in association with the secondary T lymphocyte activation increased $IFN-{\gamma}$ production and stimulated proliferation of cytotoxic T cells and suppressor T cells, indicating the activation of cell-mediated immune responses.

Simulation of a Polarimeter for a Spin-Polarized Positron Beam

  • Kim, J.H.;Saito, F.;Suzuki, N.;Wei, L.;Nagashima, Y.;Kurihara, T.;Goto, A.;Itoh, Y.;Lee, Y.S.;Hyodo, T.
    • Journal of Korean Vacuum Science & Technology
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    • 제6권3호
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    • pp.116-119
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    • 2002
  • A performance of a new positron polarimeter is investigated by simulation using a charged-particle trajectory program. The results of the ray tracing are presented along with the details of the design parameters and projected system performance. A ray tracing analysis indicates that this design is capable of effectively transmitting positrons at beam energies varying from 0.1 to 30 keV within the beam diameter of 2-6mm. However, the observed reflection of the positrons(lower than 2 keV) at 12 kGauss indicated that further refinement of beam design is needed to produce a better positron polarimeter.

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THE SPIN REORIENTATION AND THE MAGNETI ANISOTROPY IN $R_{2}Fe_{17-x}M_{x}C_{y}$ (R=Er, Tm, M=Al, Ga)

  • Ohno, K.;Urakabe, T.;Agata, M.;Saito, T.;Shinagawa, K.;Tsushima, T.
    • 한국자기학회지
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    • 제5권5호
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    • pp.437-441
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    • 1995
  • In order to consider the change of the magnetic anisotropy energy by the Al or Ga substitution for Fe, spin reorientation temperature $T_{SR}$ and Curie temperature $T_{c}$ in $R_{2}Fe_{17-x}M_{x}$ (R=Er, Tm, M=Al, Ga) have been studied both experimentally and theoretically. As a result, $T_{SR}$ and $T_{c}$ for $R_{2}Fe_{17-x}M_{x}$ shift toward higher temperature side with x ($0{\leq}x{\leq}2.0$). The ${\Delta}T_{c}$ the difference of the $T_{c}'s$ between $Er_{2}Fe_{17-x}Al_{x}$ and $Tm_{2}Fe_{17-x}Al_{x}$, is always about 10 K independent of Al-content. But in the case of Ga substitution, the ${\Delta}T_{c}$ increases with Ga-content ; especially, the ${\Delta}T_{c}$ for x=2.0 is 43 K. This value of the ${\Delta}T_{c}$ is not explained by only the difference of the de Gennes fator G between $Er^{3+}$ and $Tm^{3+}$, but it is thought that the values of $J_{ErFe}$ and $J_{TmFe}$ themselves are not equal. ($J_{AB}$ : the exchange interaction between A and B.)

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이산 웨이브렛 변환영역에서의 스펙트럼 차감법을 이용한 잡음제거 (Noise Reduction using Spectral Subtraction in the Discrete Wavelet Transform Domain)

  • 김현기;이상운;홍재근
    • 한국멀티미디어학회논문지
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    • 제4권4호
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    • pp.306-315
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    • 2001
  • 잡음환경에서의 음성인식을 위하여 음성에 부가된 잡음을 제거하는 방법에 있어, 기존의 스펙트럼 차감법은 잡음과 음성을 정확히 구별하기 힘들고 정확한 잡음의 특성을 추정할 수 없는 단점이 있다. 또한 웨이브렛 변환영역에서의 잡음제거 방법은 임계값 적용시 저주파 영역보다는 고주파영역에 상대적으로 더 큰 영향을 미쳐 고주파영역에서 신호의 손실이 발생하는 단점이 있다. 본 논문에서는 스펙트럼 차감법 및 웨이브렛 변환을 이용한 잡음제거 방법의 단점을 개선하기 위하여 연속 웨이브렛 변환 영역에서 웨이브렛 계수의 스케일별 표준편차로 묵음구간과 음성 구간을 판별하여 끝점을 검출 후, 잡음이 섞인 음성신호를 이산 웨이브렛 변화에 의해 3개의 대역으로 분리하여 각각의 대역 내에서 스펙트럼 차감법을 적용시키는 방법을 제안한다. 끝점을 검출하고 대역을 나눔으로써 스펙트럼 차감을 적응할 잡음 신호의 특성을 정확히 추출할 수 있다. 실험을 통하여 제안한 방법이 기존의 스펙트럼 차감법 및 웨이브렛 변환을 이용한 잡음제거 방법보다 신호대 잡음비 및 Itakura-Saito거리 측면에서 향상됨을 확인할 수 있었다.

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