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전이금속 불순물(W)에 의한 GaSe의 전자구조 및 자성 변화

  • 박은원
    • EDISON SW 활용 경진대회 논문집
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    • 제6회(2017년)
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    • pp.433-436
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    • 2017
  • SIESTA를 이용하여 GaSe 단일층에서 금속 원자(Ga)를 전이금속 원자(W)로 치환하였을 때($W_{Ga}$)의 구조 deformation, 에너지 안정성, 전자구조와 자성을 확인하였다. 그 결과, 구조가 바뀌면서 평면에 수직한 방향으로 구조 변형이 나타났고, $W_{Ga}$에서 W의 NN는 Se이 되었다. Clean surface만큼 $W_{Ga}$도 안정된 구조임을 알 수 있었다. $W_{Ga}$에서 W에 의한 defect states가 up, down 6개씩 split되어 나타났으며, ${\Gamma}$ point에서 degenerated 경향을 보였다. 또한 W에 의한 magnetic moment는 $1{\mu}_B$인 것을 확인하였다. Defect states는 degenerated $d_{yz}$, $d_{zx}$ orbital character, degenerated $d_{xy}$, $dx^2-y^2$ orbital character, defect states는 $d_z{^2}$ orbital character을 띠는 것으로 나뉘었고, 이에 따라 에너지가 함께 높아졌다.

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TOEPLITZ TYPE OPERATOR IN ℂn

  • Choi, Ki Seong
    • 충청수학회지
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    • 제27권4호
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    • pp.697-705
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    • 2014
  • For a complex measure ${\mu}$ on B and $f{\in}L^2_a(B)$, the Toeplitz operator $T_{\mu}$ on $L^2_a(B,dv)$ with symbol ${\mu}$ is formally defined by $T_{\mu}(f)(w)=\int_{B}f(w)\bar{K(z,w)}d{\mu}(w)$. We will investigate properties of the Toeplitz operator $T_{\mu}$ with symbol ${\mu}$. We define the Toeplitz type operator $T^r_{\psi}$ with symbol ${\psi}$, $$T^r_{\psi}f(z)=c_r\int_{B}\frac{(1-{\parallel}w{\parallel}^2)^r}{(1-{\langle}z,w{\rangle})^{n+r+1}}{\psi}(w)f(w)d{\nu}(w)$$. We will also investigate properties of the Toeplitz type operator with symbol ${\psi}$.

비-동질 안정 프로세스 기반 임베디드 시스템 소프트웨어의 신뢰성 특성에 관한 연구 (A study on the Reliability System Software based on NHPP(Non-Homogeneous Poisson Process)

  • 한상섭;백영구;이근석;전현덕;류호중;이기서
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2001년도 춘계학술대회 논문집
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    • pp.347-358
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    • 2001
  • In this paper, we apply NHPP model example to s/w process in order to get to know s/w reliability. The test is constructed by a test zig of commercial product loaded real embedded system s/w. It is established to s/w reliability prediction and estimation of real-time embedded system s/w. It is computed the prediction value of cumulative failures, the failure intensity, the reliability and the estimation value of MTTF, Failure Rate. To the more realization of high reliability in the real-time embedded system s/w, if the embedded system s/w is ensured to the test coverage and constructed to stable s/w process & operating system, we can improve the performance and the reliability characteristic of the real-time embedded system s/w.

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Crystal Structure of Pentapotassium Disodium Hexatungstoantimonate(V) Dodecahydrate, $K_5Na_2[SbW_6O_{24}]\cdot12H_2O$

  • Lee, Uk;Sasaki, Yukiyoshi
    • Bulletin of the Korean Chemical Society
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    • 제8권1호
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    • pp.1-3
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    • 1987
  • The crystal structure of $K_5Na_2[SbW_6O_{24}]{\cdot}12H_2O$ has been determined. Final R = 0.081 for 890 observed independent reflections collected by diffractometry. Crystal data as follows; trigonal, space group R3m, a = 9.794(1) ${\AA},\;{\alpha}$ = 84.72$(1)^{\circ}$, Z = 1. The heteropolyanion has a structure with point symmetry $D_{3d}$ (3m), of the ideal Anderson-type heteropolyanion. The Sb-W and W-W distances are 3.259(2) and 3.259(3) ${\AA}$. Three types of W-O ($W-O_t,\;W-O_b\;and\;W-O_c$) distances are 1.73(2), 1.95(4) and 2.20(3) ${\AA}$. The Sb-O distance is 1.97(3) ${\AA}$.

패키지게임 S/W 품질모델 및 시험기법에 관한 연구 (A Study on Package Game S/W Quality Model and Testing Method)

  • 김훈;최종원
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2004년도 춘계학술발표대회
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    • pp.203-206
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    • 2004
  • 세계 게임시장의 급속한 팽창으로 인하여 게임 S/W의 경쟁력 확보를 위한 여러 방안들이 제기되고 있으며 이중 품질에 대한 논의가 대두되고 있다. 그러나 게임 S/W의 품질에 관한 국내의 연구 개발이 아직 미흡한 실정이며 게임 S/W의 품질저하로 이어지고 있다. 따라서 게임산업의 발전과 아울러 패키지게임 S/W의 품질 향상을 통해 게임 S/W의 질적 수준을 제고할 필요가 있다. 본 연구에서는 ISO/IEC 9126를 기반으로 패키지게임 S/W를 시험하여 결과를 산출할 수 있는 품질모델과 시험기법를 개발하여 패키지게임 S/W 품질평가에 적용할 수 있도록 하였다.

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THE DIMENSION OF THE SPACE OF STABLE MAPS TO THE RELATIVE LAGRANGIAN GRASSMANNIAN OVER A CURVE

  • Daewoong Cheong
    • 충청수학회지
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    • 제36권1호
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    • pp.1-8
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    • 2023
  • Let C be a smooth projective curve and W a symplectic bundle over C of degree w. Let π : 𝕃𝔾(W) → C be the relative Lagrangian Grassmannian over C and Sd(W) be the space of Lagrangian subbundles of degree w -d. Then Kontsevich's space ${\bar{\mathcal{M}}}_g$(𝕃𝔾(W), βd) of stable maps to 𝕃𝔾(W) is a compactification of Sd(W). In this article, we give an upper bound on the dimension of ${\bar{\mathcal{M}}}_g$(𝕃𝔾(W), βd), which is an analogue of a result in [8] for the relative Lagrangian Grassmannian.

WDM 네트워크에서 가상 토폴로지 재구성을 위한 VTR 컨트롤러 (The VTR Controller for reconfiguring virtual topology in WDM Networks)

  • 유승연;정영은;신석규
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2008년도 추계학술발표대회
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    • pp.917-919
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    • 2008
  • WDM 네트워크에서 QoS를 향상시키기 위해서는 가상 토폴로지를 효율적으로 재구성할 수 있어야 한다. 본 연구에서는 토폴로지를 재구성할 시점을 결정하고 적절한 파장을 할당하는 기법을 제안함으로써 효과적으로 WDM 네트워크를 운영할 수 있는 WDM 컨트롤러를 제안한다.

철도용 지상신호설비를 위한 공통 안전 H/W 플랫폼 및 안전 S/W 개발 환경 구축(사례) (Common safety H/W platform and Establishing safety S/W development environment for Ground railway signal systems)

  • 김도영;김현민;김윤배
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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    • pp.172-180
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    • 2011
  • When it essentially designs and develops the Railway Signal System H/W and S/W, It requires base to build an environment which the safety of the complete system can be certified objectively. It is not rational choice to progress the safety certification of each of the subsystems to ensure reliability from an economic point of view. Furthermore, Even though H/W and S/W already certificated the safety, In case of changing subsystem to comprise relevant system, The safety certification of its parts newly must proceed. This study to solve these problems covers safety H/W platform which is commonly applicable to composition plan at Ground railway signaling systems such as CBTC, ETCS, CBI and safety-based modeling approach with S/W development tools (SCADE) and certificated O/S (Pike) to build the development environment. In addition, When it designs and develops safety S/W, This study explains structure to separate the data section which for logical operations and logical operations itself and provides guideline to support the certification through minimizing changes to the software.

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Ultrastructural Aspects of the Mixed Infections of Watermelon Mosaic Potyvirus and Cucumber Green Mottle Mosaic Tobamovirus Isolated from Watermelon

  • Kim, Jeong-Soo;Cho, Jeom-Deog;Park, Hong-Soo;Kim, Kyung-Soo
    • The Plant Pathology Journal
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    • 제16권4호
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    • pp.211-215
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    • 2000
  • Symptoms on 4 varieties of watermelons inoculated with watermelon mosaic potyvirus II isolated from watermelon (WMV-W) were severe mosaic and leaf malformation while those inoculated with cucumber green mottle mosaic tobamovirus from watermelon (CGMMV-W) were mild mosaic and chlorotic spots. Inoculation of the mixture of WMV-W and CGMMV-W produced extremely severe mosaic along with necrotic spots and general necrosis. Doubly infected plants were also stunted. Cells infected with WMV-W or CGMMV-W alone exhibited the intrinsically ultra-structural properties of each virus infection. WMV-W induced potyvirus-characteristic cylindrical inclusions in the cytosol. Virus particles were orderly aligned along the tonoplasts. CGMMV-W induced tobamovirus-characteristic stacked crystalline arrays of virus particles in the cytosol. Cells infected doubly with WMV-W and CGMMV-W contained striking cytopathic effects that were not present in single infection of each virus. The unique ring structure, nonagon, was that a single potyvirus particle was surrounded by 9 CGMMV-W tobamovirus particles.

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[ $W_{1}/O/W_{2}$ ] Multi-emulsion Capsules Containing Ascrobic Acid-2-Glucoside Prepared Using PCL-based Amphiphilic Di- and Tri-block Copolymers

  • Cho, Heui-Kyoung;Chang, Woo-Hyuck;Cheong, In-Woo
    • 한국고분자학회:학술대회논문집
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    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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    • pp.262-262
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    • 2006
  • Biodegradable and amphiphilic di-block and tri-block copolymers, prepared with monomethoxy poly ethylene glycol (MPEG) and ${\varepsilon}-caprolactone\;({\varepsilon}-CL)$, were used for the application of W1/O/W2 multi- emulsion capsules. The effects of topology and the ratio of hydrophilic moiety of PCL-based polymers on the encapsulation efficiency of the $W_{1}/O/W_{2}$ multi-emulsion capsules containing Ascorbic Acid-2-Glucoside (AA-2-G) were investigated. The ratio of PEG and PCL was 1:0.5, 1:0.75, 1:1, and 1:1.25. PEG-PCL block copolymers were added to the first step of the preparation of $W_{1}/O$ emulsions. The dispersion stability, the particle size, the morphology of the $W_{1}/O/W_{2}$ multi-emulsion capsules were observed using an on-line turbidity meter, dynamic light scattering (DLS), a confocal microscopy (with FITC) and an optical microscopy. Biodegradable behavior of the PEG-PCL block copolymers and release behavior of AA-2-G were also observed by Gel Permeation Chromatography (GPC) and High Performance Liquid Chromatography (HPLC).

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