• 제목/요약/키워드: technology frontier

검색결과 300건 처리시간 0.031초

Introduction to IEC Standardization for Superconducting Sensors and Detectors

  • Ohkubo, M.
    • Progress in Superconductivity
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    • 제14권2호
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    • pp.106-109
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    • 2012
  • Superconducting sensors and detectors have been applied to many fields or beginning to enter the maturing stage. The applications spread over a wide range of fields such as radio telescope, medical examination, quantum information, contamination inspection, materials analysis, etc. For users of the superconducting devices as well as developers, we have to avoid confusion of naming, graphical circuit symbols, and measurement methods for device performance. We are trying to formulate international standards under the International Electrotechnical Commission - Technical Committee 90 (IEC-TC90), which is responsible for superconductivity. The sensors and detectors to be considered are divided into two groups: coherent sensors (SQUID, SIS mixers, etc.) and direct detectors (TES, STJ, MKID, SSPD, etc.).

Flame Synthesis of Silica-Coated Iron Oxide Nanoparticles and Their Characterization

  • Jun, Kimin;Yang, Sangsun;Lee, Jeonghoon;Pikhitsa, Peter V.;Choi, Mansoo
    • 한국입자에어로졸학회지
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    • 제9권4호
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    • pp.209-219
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    • 2013
  • We have used the modified diffusion flame burner to synthesize silica coated iron oxide nanoparticles having enhanced superparamagnetic property. Silica-encapsulated iron oxide particles were directly observed using a high resolution transmission electron microscope. From the energy dispersive X-ray spectroscopy (EDS) and zeta potential measurements, the iron oxide particles were found to be completely covered by a silica coating layer. X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) measurements revealed that the iron oxide core consists of ${\gamma}-Fe_2O_3$ rather than ${\alpha}-Fe_2O_3$. Our magnetization measurements support this conclusion. Biocompatibility test of the silica-coated iron oxide nanoparticles is also conducted using the protein adsorption onto the coated particle.

CONSTRUCTING DAILY 8KM NDVI DATASET FROM 1982 TO 2000 OVER EURASIA

  • Suzuki Rikie;Kondoh Akihiko
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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    • pp.18-21
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    • 2005
  • The impact of the interannual climatic variability on the vegetation sensitively appears in the timing of phenological events such as green-up, mature, and senescence. Therefore, an accurate and temporally high-resolution NDVI dataset will be required for analysis on the interannual variability of the climate-vegetation relationship. We constructed a daily 8km NDVI dataset over Eurasia based on the 8km tiled data of Pathfinder A VHRR Land (PAL) Global daily product. Cloud contamination was successfully reduced by Temporal Window Operation (TWO), which is a method to find optimized upper envelop line of the NDVI seasonal change. Based on the daily NDVI time series from 1982 to 2000, an accurate (daily) interannual change of the phenological events will be analyzed.

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CRW 비행체의 공력특성 해석 (Analysis on Aerodynamic Characteristics of the CRW Air-Vehicle)

  • 최성욱;김재무
    • 한국전산유체공학회지
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    • 제8권4호
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    • pp.26-33
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    • 2003
  • Smart UAV Development Program, one of the 21c Frontier R&D Program sponsored by MOST(Ministry of Science and Technology), was launched in 2002 As an air vehicle for the Smart UAV, CRW(Canard Rotor/wing) concept was one of the candidates compared in trade-off study. The CRW concept has not only been proven completely but its aerodynamic characteristics not known in detail yet. Two calculation methods were adopted in this study to obtain aerodynamic data for the CRW First method was the superpose DATCOM method which is capable of three lifting sufaces, and second one is the full Navier-Stokes computation around CRW configuration using overset grid method. Basic aerodynamic characteristics of the CRW configuration was analyzed and the minimum drag level with lift to drag ratio is presented. The peculiar flow characteristics around rotor/wing and hub were also examined and considered in the configuration design.

Metabotropic glutamate receptor dependent long-term depression in the cortex

  • Kang, Sukjae Joshua;Kaang, Bong-Kiun
    • The Korean Journal of Physiology and Pharmacology
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    • 제20권6호
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    • pp.557-564
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    • 2016
  • Metabotropic glutamate receptor (mGluR)-dependent long-term depression (LTD), a type of synaptic plasticity, is characterized by a reduction in the synaptic response, mainly at the excitatory synapses of the neurons. The hippocampus and the cerebellum have been the most extensively studied regions in mGluR-dependent LTD, and Group 1 mGluR has been reported to be mainly involved in this synaptic LTD at excitatory synapses. However, mGluR-dependent LTD in other brain regions may be involved in the specific behaviors or diseases. In this paper, we focus on five cortical regions and review the literature that implicates their contribution to the pathogenesis of several behaviors and specific conditions associated with mGluR-dependent LTD.

내압을 받는 Y 배관의 크리프 수명 평가를 위한 3차원 응력해석 (3-Dimensional Stress Analysis for Creep Life Assessment of Y-Piece Under Inner Pressure)

  • 신규인;이진상;윤기봉
    • 한국안전학회지
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    • 제22권2호
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    • pp.22-27
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    • 2007
  • To assess a creep life of elevated temperature plant components, inspections and analysis are usually focused on the critical locations. In this study, stress analysis of a weld region in branch part of Y-piece was conducted by using a three-dimensional finite element analysis. The stresses at the inner and outer surface in the weld part were estimated by using elastic and elastic-creep analysis. For the elastic-creep analysis two kinds of elastic-creep analysis was conducted. The one was assumed that base and weld material properties were same and the other was that material properties were different between base and weld metal. The material properties of base and weld metal were used from reference data. The results showed the stress relaxation level and its location. The result stresses are also compared with elastic stresses.

Optoelectronic Properties Enhanced by Photodynamic Patterning of Azo Polymers

  • Kim, Dong-Yu
    • 한국고분자학회:학술대회논문집
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    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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    • pp.25-26
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    • 2006
  • Azobenzene functionalized polymers have been extensively investigated due to the potential applications in the areas of optical switching, optical elements, optical information storage, and nonlinear optics. These applications are mainly achievable due to photoinduced properties of azobenzene groups with photoisomerization and photoinduced anisotropy. We report applications to the optoelectronic devices using inscribed one-(1D) and two-dimensional (2D) SRGs on azo polymer films. The inscribed holographic SRGs patterns were useful to control or enhance optoelectronic properties such as transparent electrode patterning, hybrid solar cell and ultraviolet GaN-based LED.

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비모수적 방법을 이용한 OECD 국가별 R&D 효율성과 생산적 분석

  • 박수동;홍순기
    • 기술혁신연구
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    • 제11권2호
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    • pp.151-173
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    • 2003
  • This paper analyses the efficiency and productivity of R&D system across time (1991${\sim}$2000) and 16 OECD countries using multi-output and multi-input non-parametric frontier methods such as DEA (data envelopement analysis) and Malmquist productivity indexes. Malmquist productivity indexes are decomposed into two components measures, namely technical change and efficiency change. To calculate R&D efficiency and productivity, we used R&D stock and the number or researchers as R&D input proxies and the number of adjusted SCI papers and U.S. patent applications as R&D output proxies. Empirical result shows that Switzerland, Canada, U.S., Australia's R&D efficiencies are the highest and Korea's R&D productivity growth is the highest in the sample for the period. Technical efficiency growth was a more important source of productivity growth than technological innovation.

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정밀연삭기의 전해드레싱 시스템 개발사례 (Development of Grinding Dressing System by Using Inprocess Electrelytic Dressing)

  • 김정두
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1998년도 춘계학술대회 논문집
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    • pp.196-202
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    • 1998
  • Recently, developments in the frontier industry have brought a rapid increase in the use of brittle materials such as silicon wafer, ferrite, sintered carbide, MgO single crystal and die steel. Because of high hardness and brittleness the cracking and chipping are apt to generate in the grinding of brittle materials, but have replaced gradually the high precision grinding. In this study, the optimum system of in-process electrolytic dressing controlled by computer was developed for improving the defects, and could maintain the optimum dressing condition at all times. The control of in-process dressing was simplified using this system, was able to maintain a stable dressing current and was unrelated to the change of dressing condition according to the variation of gap and oxide layer. Therefore, the optimum in-process electrolytic dressing system was constructed and the analysis of grinding mechanism with this system was studied.

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New Approach to the Analysis of Palindromic Structure in Genome Sequences

  • Kim, Seok-Won;Lee, Yong-Seok;Choi, Sang-Haeng;Chae, Sung-Hwa;Kim, Dae-Won;Park, Hong-Seog
    • Genomics & Informatics
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    • 제4권4호
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    • pp.167-169
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    • 2006
  • PABAP (Palindrome Analysis by BLAST Program) is an analysis system that identifies palindromic sequences from a large genome sequence up to several megabases long. It uses NCBI BLAST as a searching engine, and data processing such as alignment filtration and detection of inverted repeats which satisfy user-defined parameters is performed by manipulating data after populating into a MySQL database. PABAP outperforms publicly available palindrome search program in that it can detect large palindrome with internal spacer at a faster speed from bacterial genomes. It is a standalone application and is freely available for noncommercial users.