• Fibers and Polymers
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• 제3권1호
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• pp.8-13
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• 2002

The effect of block sequence on the self-assembly of ABC-type triblock copolymers in the ordered state is investigated using an isothermal-isobaric molecular dynamics simulation. The block sequence has an important effect ,on the ]norphology of ABC triblock copolymers. Different morphologies are observed depending on the block sequence as well as the block composition. The triblock copolymers with the volume fraction of 1 : 1 : 1 ($f_A$=$f_B$=$f_C$= 0.33) show the three phase and four layered lamellar structures irrespective of the block sequence. The $A_{32}$$B_{16}$$C_{32}$triblock copolymer with $f_B$=0.2 shows a morphology In which cylinders of midblock B are formed at the interface between A and C lamellae, whereas the morphology of triblock copolymer $B_{16}$$C_{32}$ $A_{32}$ and $C_{32}$ $A_{32}$ $B_{16}$ show a cylindrical core-shell structure and a lamellar type morphology, respectively. The $A_{20}$$B_{40}$$C_{20}$the triblock copolymer with the block B as a major component shows a tricontinuous structure, whereas both $B_{40}$$C_{20}$$A_{20}$ and $C_{20}$$A_{20}$$B_{40}$ triblock coolymers exhibit the lamellar structures. When the block B has larger volrome fraction with $f_B$=0.75, the matrix is composed of block B, and other two blocks A and C form spherical domains.

• 대한토목학회논문집
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• 제36권4호
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• pp.667-675
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• 2016

본 연구는 향후 교통수요관리를 위한 기초 자료로 활용하고자 가구별 차량보유패턴 및 보유구조를 분석하였다. 차량등록대수와 가구당 차량보유대수가 증가하는 현시점에 가구별 차량보유실태를 통해 보유패턴에 대해 알아 볼 필요가 있다. 또한 차량 증가 원인에 대해 분석 할 필요가 있을 것이다. 가구통행실태 조사의 결과를 바탕으로 승용차를 보유하고 있는 가구와 승용차 및 비승용차 보유하는 가구로 구분하여 연구를 진행하였고 주요 결과는 다음과 같다. 차량보유구조 패턴을 통해 가구당 차량보유대수가 2대 이하인 경우에는 승용차만을 보유하는 가구수가 많았으며 3대 이상의 경우 승용차만 보유하는 가구보다 비승용차와 함께 보유하는 가구 비율이 증가한다는 것을 알 수 있었다. 순서형 로짓 모형을 활용하여 가구별 차량 보유구조를 분석한 결과 가구 속성 자료 및 주거형태 변수에 따라 차량보유에 영향을 주는 요인들이 차이가 있는 것으로 나타났다.

• 한국자기학회지
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• 제18권5호
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• pp.190-194
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• 2008

FePd 합금박막을 스퍼터링법으로 초격자 박막의 형태로 제작하고 기판온도, 조성변화에 따른 미세구조 및 자기적 특성을 분석하였다. FePd 합금박막의 규칙화를 위한 열처리 온도를 FePt의 열처리 온도에 비해 $150^{\circ}C$ 낮추는데 성공하였다. 또한 FePd 규칙화 합금 박막은 화학양론적 조성일 때 장범위 규칙도는 가장 높은 값을 가졌으며(Fe조성 50 at.%, S = 0.79), 자기이방성 에너지는 Fe 조성이 약간 낮은 조성에서(Fe조성 48 at.%, $K_U=1.6{\times}10^7\;erg/cm^3$) 가장 높은 값을 나타내었다. 이것은 FePd 합금박막의 조성이 장범위 규칙도와 수직자기이방성에 직접적으로 영향을 미친다는 것을 나타낸다.

• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3777-3787
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• 2012

Three kinds of 3D isomorphous and isostructural coordination polymers, namely, $\{[Ln_2(PDA)_3(H_2O)_3]{\cdot}0.25H_2O\}_{\infty}$ (Ln = La(1), Sm(2), and Gd(3)) ($PDA^{2-}$ = pyridine-2,6-dicarboxylate anion) have been synthesized under hydrothermal conditions and characterized by elemental analyses, IR spectroscopy, thermal analyses and single crystal X-ray diffraction. In these MOFs, Ln(III) centers adopt eight-coordinated and nine-coordinated with the $N_1O_7$ and $N_2O_7$ donor sets to construct distorted trianglar dodecahedron geometry and tricapped trigonal prism configurations, respectively. Based on the building block of tetranuclear homometallic $Ln_4C_4O_8$ unit (16-membered ring), 1-3 are connected into highly ordered 2D sheets via O-C-O linkers and further constructed into 3D architectures through hydrogen bonds. Crystallographic parameters suggest that the lanthanide contraction effect exist in these coordination polymers. Luminescent properties of the lanthanide-based MOFs (metal-organic frameworks) have been measured at room temperature, which reveal that they presenting ionselective characters toward certain metals, such as $Mg^{2+}$, $Cd^{2+}$ and $Pb^{2+}$ ions.

• 한국실내디자인학회논문집
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• 제21권5호
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• pp.264-271
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• 2012

As changed population structure variously, population decrease is one of the important problem in present urbanization. It resulted decline of the medium-large size housings that increasing of 1-2 person household need the variety of small housing with housing type. This study was researched the Gold-Generation on theme by Gold Miss, Gold Mr. who preferring urban small housings that it analyzed survey of Gold generation who be wanted urban small housing by interior coordination elements. Data to be analyzed that first, Gold Mr. and Miss are preferred two bedroom applied by spatial structure coordination. Especially it is based on the separation between livingroom and bedroom with duplex type which is bathroom formed single unit type(shower/toilet/basin). In interior coordination of spatial elements, Gold Mr. considered the form of kitchen with huge ㄷ type instead of Gold Miss are preferred alpha room or alpha space to use powder room or dress room. Second, In Preference of interior coordination elements, Gold Mr. and Miss are preferred bed-clothes and curtains by fabrics, lighting are hanging and spot lighting, accessories are carpet with rug and porcelains. Color are preferred bright scheme both white and ivory, however preference of furniture is different from Gold Mr. and Gold Miss that Gold Mr. are ordered desk, sofa and shelves but Gold Miss are preferred sofa, bed, and dressing table. It showed between Gold Mr. and Gold Miss are equal needs or differences. It expects the basic research for understanding the interior coordination elements for preference in urban small housing as focused on Gold generation(Gold Miss, Gold Mr.) that they will be applied the interior space on urban small housing.

• 생명과학회지
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• 제7권3호
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• pp.161-166
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• 1997

HIV-1 Rev단백질은 바이러스의 구조단백질의 발현조절에 매우 중요한 역할을 하며RNA가 1차발현된 원형대로 또는 일부만이 절단/재조합된 상태로 세포질에 집적되는 것을 가능하게 한다. env gene에 존재하는 Rev-responsive element RNA는 복잡한 RNA구조를 지니면서 Rev의 기능을 위하여 필수적으로 필요시 된다. 그러나 이러한 절차의 완전한 진행을 위해서는 핵단백질이 요구되는 것으로 추정된다. 본 연구에서는 electrophoretic mobility shift, UV-crosslinking 또는 SDS/PAGE등의 실험을 통하여 36/37, 56, 41, 76, 150 kD등의 핵단백질등이 RRE RNA와 결합반응하는 것을 발견하였으며 특히 36/37 과 56 kD 단백질을 5분간의 자외선조사에 의해 특히 RRE RNA에 결합하는 핵단백질들은 gel mobility shift assay에서 Rev RNA인식결합에 경쟁적인 특징을 나타내고 있다.

• 대한금속재료학회지
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• 제48권3호
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• pp.262-267
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• 2010

$LiNi_{1-x}Mg_xO_2$(x=0, 0.025, 0.05, 0.075, 0.1) samples were synthesized by the solid-state reaction method. The crystal structure was analyzed by X-ray powder diffraction and Rietveld refinement. $LiNi_{1-x}Mg_xO_2$samples give single phases of hexagonal layered structures with a space group of R-3m. The calculated cation-anion distances and angles from the Rietveld refinement were changed with Mg contents in $LiNi_{1-x}Mg_xO_2$. The thicknesses of $NiO_2$ slabs were increased and the distances between the $NiO_2$ slabs were decreased with the increase in Mg contents in the samples. The electrical conductivities of sintered $LiNi_{1-x}Mg_xO_2$ samples were around $10^{-2}$ S/cm at room temperature. The electrochemical performances of $LiNi_{1-x}Mg_xO_2$were evaluated by coin cell test. Compared to $LiNiO_2$, $LiNi_{0.95}Mg_{0.05}O_2$ exhibited improved high-rate capability and cyclability due to the well-ordered layered structure by doping of Mg ion.

• 한국컴퓨터정보학회논문지
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• 제14권12호
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• pp.127-137
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• 2009

본 논문에서는 다중모드를 갖는 장치 구성요소들의 네트워크 구조를 갖는 시스템 혹은 통신 네트워크에서 성능 품질 혹은 신뢰도 근사계산을 위해서 네트워크 시스템 상태들의 확률크기에 관해 최고 가능 상태들만을 생성하는 알고리즘을 제안한다. 대부분의 네트워크 시스템 같은 복잡한 시스템들은 장치들의 수나 장치들의 다중 모드의 수가 증가함에 따른 기하급수적 상태 공간의 증가로 인해 그 성능이나 신뢰도를 직접 계산하는 것이 매우 어려운 경우가 많다. 따라서 근사계산의 해법이 더욱 타당한 접근법이라 할 수 있다. 이때, 시스템의 기대 성능이나 신뢰도 계산을 위해서는 시스템 상태와 그 상태 확률을 통해 기댓값을 산출하여야 한다. 이때, 근사계산을 통한 접근 방법에서 사전에 수행되어야 하는 것은 네트워크 시스템 상태들의 발생 가능 순서로 나열해야 하는 것이 필요하다. 이에 본 논문에서는 시스템 상태들 중 가장 발생 가능성이 큰 상태들을 찾고 이로부터 네트워크 성능이나 신뢰도의 근사 값을 구하는데 활용할 수 있는 방법을 제안한다. 제안된 알고리즘은 기존의 방법과 자원의 효율성 측면 중에서 메모리 효율성을 고려하여 실험을 통해 예시하고 장 단점을 논의하고자 한다.

• 한국수산과학회지
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• 제38권3호
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• pp.143-147
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• 2005

Relationship between structure and biological activity was performed using the five substance P-related peptides (SPRPs) [mammalian-SP (M-SP), cod-SP (C-SP), trout-SP (T-SP), lungfish-SP (L-SP) and Ranakinin] and four SP analogs [[$His^5$]-SP (5H-SP), [$Gly^5$]-SP (5G-SP), ($Ile^8$)-SP (8I-SP) and ($Trp^8$)-Ranakinin (8W-Ranakinin)]. The circular dichroism (CD) spectra showed that all of the peptides took an unordered structure in buffer solution and artificial liposomes. However, 8W-Ranakinin undergoes conformational changes by being transferred into neutral and acidic liposomes from an unordered structure to more ordered structure. The arterial relaxing effect of the peptides was also studied with guinea-pig aorta (GPA), As a result of the studies, L-SP was about 14-fold more potant than M-SP. The order of potency compared to $EC_{50}$ value was $L-SP{\gg}M-SP>5G-SP{\ge}8I-SP>5H-SP>T-SP$, C-SP, Ranakinin, 8W-Ranakinin.

• 열처리공학회지
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• 제19권1호
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• pp.10-19
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• 2006

Microstructure and morphology of precipitates in $Ni_3Al$- and TiAl-based intermetallics containing carbon have been investigated in terms of transmission electron microscopy(TEM). In an $L1_2$-ordered $Ni_3Al$ alloy with 4 mol.% of chromium and 0.2~3.0 mol.% of carbon, fine octahedral precipitates of $M_{23}C_6$ type carbide were formed in the matrix by aging at temperatures around 973 K after solution annealing at 1423 K. TEM examination revealed that the $M_{23}C_6$ phase and the matrix lattices have a cube-cube orientation relationship and keep partial atomic matching at the {111} interface. After prolonged aging or by aging at higher temperatures, the $M_{23}C_6$ precipitates then adopt a rod-like morphology elongated parallel to the <100> directions. In the $L1_0$-ordered TiAl containing 0.1~2.0 mol.% carbon, TEM observations revealed that needle-like precipitates, which lie only in one direction parallel to the [001] axis of the $L1_0$ matrix, appear in the matrix and preferentially at dislocations. Selected area electron diffraction(SAED) patterns analyses have shown that the needle-shaped precipitate is $Ti_3AlC$ of perovskite type. The orientation relationship between the $Ti_3AlC$ and the $L1_0$ matrix is found to be $(001)_{Ti3AlC}//(001)_{L10\;matrix}$ and $[010]_{Ti3AlC}//[010]_{L10\;matrix}$. By aging at higher temperatures or for longer period at 1073 K, plate-like precipitates of $Ti_2AlC$ with a hexagonal structure are formed on the {111} planes of the $L1_0$ matrix. The orientation relationship between the $Ti_2AlC$ and the $L1_0$ matrix is $(0001)_{Ti2AlC}//(111)_{L10\;matrix}$ and $_{Ti2AlC}//_{L10\;matrix}$.