• Title/Summary/Keyword: Aligned transfer

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Monolithic Integration of Arrays of Single Walled Carbon Nanotubes and Sheets of Graphene

  • Hong, Seok-Won
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2012.05a
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    • pp.68.2-68.2
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    • 2012
  • We present a scheme for monolithically integrating aligned arrays of single walled carbon nanotubes (SWNTs) with sheets of graphene, for use in electronic devices. Here, the graphene and arrays of SWNTs are formed separately, using chemical vapor deposition techniques onto different, optimized growth substrates. Techniques of transfer printing provide a route to integration, yielding two terminal devices and transistors in which patterned structures of graphene form the electrodes and the SWNTs arrays serve as the semiconductor. Electrical testing and analysis reveal the properties of optically transparent transistors that use this design, thereby giving insights into the nature of contacts between graphene and SWNTs.

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A Numerical Study on Performance Characteristics of a Closed Circuit Cooling Tower with Multi Paths (멀티패스 밀폐식 냉각탑의 성능특성에 대한 수치적 연구)

  • Kim, Eun-Pil
    • Journal of Advanced Marine Engineering and Technology
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    • v.32 no.4
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    • pp.528-533
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    • 2008
  • A closed circuit cooling tower having high temperature of cooling water and small water flow rate is investigated. To study the characteristics of the heat transfer of heat exchanges in a cooling tower with multi paths a numerical method is used. The results show that the staggered tube arrangements in a bank show better performance than aligned ones for temperature variation with various outer diameters of tube bundles. In case of one pass, the 15.88 mm tube case shows about 9% better performance than the 25.4 mm tube case. In two paths, the tube outside diameter of 15.88 mm show about 14.4% better results than the 25.4 mm diameter case.

Wide-angle optical design using high-resolution uncooled thermal detector

  • Lee, Jonghoon
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.11
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    • pp.31-37
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    • 2017
  • In this paper, we propose efficient design and construction of an infrared wide angle optical system with low distortion utilizing a high resolution detector for automobile application. The operational convenience and the recognition ability have been improved significantly by applying the high resolution uncooled thermal detector with wide angle optical design. The active ahtermalization mechanism is implemented so that the adjustment of the optical component of the system is to be made automatically according to the temperature change by motorized control. The modulation transfer function (MTF) is about 50% at the Nyquist frequency close the diffraction limit. The distortion is less than 5% at the edge field. As a result, a high-resolution uncooled thermal optical system with wide field of view (FOV) is assembled, aligned and its performance is tested successfully.

Creation of System Dynamics in an Uncertain and Complex Market: The Case of Korea's Evolving Biopharmaceutical Industry

  • Lee, Jeong Hyop;Kim, Jaewon;Hyeon, Byung-Hwan
    • Asian Journal of Innovation and Policy
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    • v.8 no.2
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    • pp.180-207
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    • 2019
  • This article explores the historical evolutionary process of the biopharmaceutical industry of Korea, and how intentional and unintentional policy interventions have triggered the creation of the industry's system dynamics and paved the way for the generation of a few global leading products, including biosimilar, as well as next-generation therapeutics of gene and cell. The policies cover the simple technology transfer of API synthesis to overcome the endemic parasitic disease, new substance patent adoption and new drug development consortia, human resource development, various national initiatives influenced by the Human Genome Project, and venture promotion schemes. The scope and implementation tools under these policies have been aligned and refined to transform traditional fine chemical-based pharmaceuticals, to stimulate large companies' participation and to create technology-based venture companies in the biopharma business of Korea.

Boron Nitride Films Grown by Low Energy Ion Beam Assisted Deposition

  • Park, Young-Joon;Baik, Young-Joon;Lee, Jeong-Yong
    • The Korean Journal of Ceramics
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    • v.6 no.2
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    • pp.129-133
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    • 2000
  • Boron nitride films were synthesized with $N_2$ion flux of low energy, up to 100 eV, at different substrate temperatures of no heating, 200, 400, 500, and $800^{\circ}C$, respectively. Boron was supplied by e-beam evaporation at the rate of $1.5\AA$/sec. For all the conditions, hexagonal BN (h-BN) phase was mainly synthesized and high resolution transmission electron microscopy (HRTEM) showed that (002) planes of h-BN phase were aligned vertical to the Si substrate. The maximum alignment occurred around $400^{\circ}C$. In addition to major h-BN phase, transmission electron diffraction (TED) rings identified the formation of cubic BN (c-BN) phase. But HRTEM showed no distinct and continuous c-BN layer. These results suggest that c-BN phase may form in a scattered form even when h-BN phase is mainly synthesized under small momentum transfer by bombarding ions, which are not reconciled with the macro compressive stress model for the c-BN formation.

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Fundamental Study for Reformation of Safety Standard about Portable Butane Gas Range (이동식 부탄 연소기의 안전기준 개정을 위한 기초 연구)

  • Kim, Sooik;Keum, Kuk Bin;Yu, Byeonghun;Lee, Chang-Eon;Kim, Young-Gu
    • Journal of the Korean Society of Combustion
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    • v.19 no.4
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    • pp.35-41
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    • 2014
  • The experiment was conducted to measure temperature and pressure around operating portable butane gas ranges with oversized cookwares. In this experiment, portable butane gas range with different safety equipment and two kinds of oversized cookware, each of which is made of aluminum alloy and rock, was used. As a result, temperature of the bottom of the butane and the pressure of butane barrel tend to aligned with each other. Through this result, it is reasonable that a safety criteria can be decided based on the temperature of the bottom of butane. Especially, portable butane gas ranges are safely conducted under the condition of the temperature is under 50 degree and pressure is under 500 kPa, respectively, at the bottom of the butane barrel.

Kinematic properties of the Ursa Major Cluster

  • Kim, YoungKwang;Lee, Young Sun;Beers, Timothy C.
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.2
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    • pp.30.3-31
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    • 2015
  • We present a kinematic analysis of 172 likely member galaxies of the Ursa Major Cluster. In order to understand the dynamical state of the cluster, we investigate the correlation of the cluster morphology with rotation, the velocity dispersion profile, and the rotation amplitude parallel to the global rotation direction. Both the minor axis and the rotation are very well-aligned with the global rotation axis in the outer region at half radius (> 0.5 $R_{max}$), but not in the inner region. The cluster exhibits low velocity dispersion and rotation amplitude profiles in the inner region, but higher in the outer. Both profiles exhibit outwardly increasing trends, suggesting an inside-out transfer of angular momentum of dark matter via violent relaxation, as revealed by a recent off-axis major-merging simulation. From Dressler-Schectman plots in the plane of galactic positions, and velocity versus position angle of galaxy, we are able to divide the Ursa Major Cluster into two substructures: Ursa Major South (UMS) and Ursa Major North (UMN). We derive a mass of $3.2{\times}10^{14}M_{\odot}$ for the cluster through the two-body analysis by the timing argument with the distance information (37 for UMN and 36 for UMS) and the spin parameter of ${\lambda}=0.049$. The two substructures appear to have passed each other 4.4 Gyr ago and are moving away to the maximum separation.

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Assembly of Biomimetic Peptoid Polymers

  • Nam, Gi-Tae
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2011.05a
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    • pp.10.2-10.2
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    • 2011
  • The design and synthesis of protein-like polymers is a fundamental challenge in materials science. A biomimetic approach is to explore the impact of monomer sequence on non-natural polymer structure and function. We present the aqueous self-assembly of two peptoid polymers into extremely thin two-dimensional (2D) crystalline sheets directed by periodic amphiphilicity, electrostatic recognition and aromatic interactions. Peptoids are sequence-specific, oligo-N-substituted glycine polymers designed to mimic the structure and functionality of proteins. Mixing a 1:1 ratio of two oppositely charged peptoid 36 mers of a specific sequence in aqueous solution results in the formation of giant, free-floating sheets with only 2.7 nm thickness. Direct visualization of aligned individual peptoid chains in the sheet structure was achieved using aberration-corrected transmission electron microscopy. Specific binding of a protein to ligand-functionalized sheets was also demonstrated. The synthetic flexibility and biocompatibility of peptoids provide a flexible and robust platform for integrating functionality into defined 2D nanostructures. In the later part of my talk, we describe the use of metal ions to construct two-dimensional hybrid films that have the ability to self-heal. Incubation of biomimetic peptoid polymers with specific divalent metal ions results in the spontaneous formation of uniform multilayers at the air-water interface. We anticipate that ease of synthesis and transfer of these two-dimensional materials may have many potential applications in catalysis, gas storage and sensing, optics, nanomaterial synthesis, and environmentally responsive scaffolds.

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Applying Theory Informed Global Trends in a Collaborative Model for Organizational Evidence-based Healthcare

  • Lockwood, Craig
    • Journal of Korean Academy of Nursing Administration
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    • v.23 no.2
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    • pp.111-117
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    • 2017
  • Getting evidence in to practice tends to focus on strategies, theories and studies that aim to close the gap between research knowledge and clinical practice. The evidence to practice gap is more about systems than individual clinician decision making. The absence of evidence for administration and management in the organization of healthcare is persistent. Teaching nurses and providing evidence as the solution to evidence-based healthcare is no longer axiomatic. Previous studies have concluded that unit level strategies integrate multi-professional teams with organizational needs and priorities. This 'best fit' approach that characterizes how healthcare is structured and delivered. The published literature shows that increased readiness for change is aligned with integrated approaches informed by conceptual models. The Joanna Briggs Collaboration is the largest global collaboration to integrate evidence within a theory informed model that brings together academic centres, hospitals and health systems for evidence synthesis, transfer and implementation. The best approaches to implementation are tailored to local culture and context, benchmark against international evidence, combine a theory informed model and stakeholder perspectives to improve the structure and processes of health care policy and practice.

The Study of Charge Transfer Mechanism in Single Crystal Iron Perovskite (단결정 철 페롭스카이트의 전하전이 연구)

  • Uhm Young-Rang;Rhee Chang-Kyu;Kim Chul-Sung
    • Journal of Powder Materials
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    • v.13 no.2 s.55
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    • pp.112-118
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    • 2006
  • [ $R_{1/3}Sr_{2/3}FeO_{3}$ ](R=Pr, Nd, and Sm) was synthesized and their magnetic properties and charge ordering(CO) transition related with lattice dynamics and oxygen vacancy were systematically investigated. The charge disproportion ation(CD) in $R_{1/3}Sr_{2/3}FeO_{3}$(R=Pr,Nd) was in which two kins of iron with valence state $Fe^{3+}$ and $Fe^{5+}$ were found with ratio of 2:1. In this charge ordering state a sequence of $Fe^{3+}Fe^{3+}Fe^{5+}Fe^{3+}Fe^{3+}Fe^{5+}$ exists aligned along the [111] direction of the pseudocubic perovskite structure. The charge ordering exist in distorted structure involving $t_{pd}$ hybridization. The disordering phases coexist in distorted structure as temprature in creases that is controlled amount of oxygen vacancy. The magnetic hyperfine fields indicate charge tranfering temperature as it dissapeared drastically.