• Title/Summary/Keyword: Basic Research

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Low molecular amorphous spirobifluorene derivatives for blue electroluminescence

  • Lee, Hyo-Young;Oh, Ji-Young;Chu, Hye-Yong;Lee, Jeong-Ik;Kim, Seong-Hyun;Yang, Yong-Suk;Do, Lee-Mi;Zyung, Tae-Hyoung
    • 한국정보디스플레이학회:학술대회논문집
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    • 2001.08a
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    • pp.209-212
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    • 2001
  • We report the synthesis and characterization of new alkoxy substituted spirobifluorene derivatives. The spiro compounds having alkoxy hydrocarbon chains were readily soluble in common organic solvents, having improved film-forming properties and had a significantly reduced tendency to crystallize, resulting in increasing their service lifetime. The results of DSC showed that it was amorphous. The optical and electroluminescent spectra were characterized. Electroluminescence (EL) properties of three-layer light emitting diodes (LED) of $ITO/TPD/spirobifluorene/Alq_3/LiF/Al$ as the active layer were characterized. Blue emission peaking of the EL spectrum of the three-layer device at 402 nm and a luminance of 3,125 $cd/m^2$ were achieved at a drive voltage 12.8 V. The luminous efficiency was obtained to be 1.7 lm/W. The color coordinate in CIE chromaticity is (0.16, 0.09), which is in a pure blue region. The external quantum efficiency was obtained to be 2.0%. The results indicate that the spirobifluorene compounds having alkoxy hydrocarbon chains are strongly potential blue emitters for LED applications.

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Ultrastructural Abnormalities in APP/PSEN1 Transgenic Mouse Brain as the Alzheimer's Disease Model

  • Kim, Mi Jeong;Huh, Yang Hoon;Choi, Ki Ju;Jun, Sangmi;Je, A Reum;Chae, Heesu;Lee, Chulhyun;Kweon, Hee-Seok
    • Applied Microscopy
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    • v.42 no.4
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    • pp.179-185
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    • 2012
  • Alzheimer's disease (AD) is a progressive neurodegenerative disorder. Neuropathological hallmarks of AD are amyloid plaques, dystrophic neurite, and alteration of subcellular organelles. However, the morpho-functional study of this degenerative process and ultimate neuronal death remains poorly elucidated. In this study, immunohistochemical and ultrastructural analyses were performed to clarify the abnormal morphological alterations caused by the progression of AD in APP/PSEN1 transgenic mice, express human amyloid precursor protein, as a model for AD. In transgenic AD mice brain, the accumulation of Amyloid ${\beta}$ plaques and well-developed dystrophic neurites containing anti-LC3 antibody-positive autophagosomes were detected in the hippocampus and cortex regions. We also found severe disruption of mitochondrial cristae using high-voltage electron microscopy and three-dimensional electron tomography (3D tomography). These results provide morpho-functional evidence on the alteration of subcellular organelles in AD and may help in the investigation of the pathogenesis of AD.

Analysis of National Basic Research System: The Case of South Korea

  • Kwon, Ki-Seok;Park, So-Yeon;Jang, Duckhee
    • Asian Journal of Innovation and Policy
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    • v.6 no.2
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    • pp.152-169
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    • 2017
  • In this paper, we analyze the basic research system in South Korea. We propose a national basic research system consisting of value, openness, input, transformation, and output. Based on this framework, we set up interview questionnaires, and 15 key informants have been interviewed. According to our results, first, in terms of value, basic research is recognized as an activity for creating knowledge in the understanding of nature. Second, as for openness, scientists and policy experts agree that active interaction with the global community is an important value for the national research system. Third, in terms of sustainable research resources, scientists are strongly required to effectively allocate research funding, maximizing the creativity of researchers and the efficient sharing of research equipment. Fourth, in transformation, basic researchers maintain that the Korean research system has is extremly dependent on the government's external control, and its self-regulative system has been weak for over half century onw. Fifth, for global competitiveness, the interviewees agreed that the quality of basic research in Korea is approaching that of its global competitors. Finally, we put forward some policy implications on the basis of these findings.

The Development of Torso & Sleeve Basic Pattern for Wedding Dress (웨딩드레스를 위한 토르소 및 소매 원형 개발)

  • Hong, Geun-Hye;Jang, Jeong-Ah
    • Fashion & Textile Research Journal
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    • v.13 no.4
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    • pp.614-623
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    • 2011
  • The purpose of this study is to develop a wedding dress basic torso pattern and sleeve pattern considering good fit and aesthetic for figures of Korean brides in their 20s. For the research method, 3 women in their 20s who has the body size of ${\pm}$ S.D range of average figure and dress form suggested by 'the 5th human body measurement' of Size Korea were selected as the test group. The evaluators are 8 clothing construction majors, and the evaluation items included total 22 questions related to torso and total 10 questions related to sleeves. The evaluation was made using 5 Likert point scale. 4 prototypes for basic dress pattern were selected through the literature search. After compare analyzing design methods of prototypes, the real wedding dresses were made in the average size of women in their 20s and the dresses were tried on for the assessment. The data was analyzed using SPSS 18.0 Program to examine average, standard deviation and significant differences between basic patterns. Based on the results of the first and the second try-on assessments, a new wedding dress basic pattern with maximized strengths of compared prototypes was completed. The details of result follows. As for dress torso basic pattern, A pattern, which had the highest overall silhouette satisfaction and scores in basic pattern analysis and try-on assessments, was selected as the prototype, and a research basic pattern reflecting strengths of each basic pattern was developed. As for dress sleeve basic pattern, B pattern, which had the highest overall silhouette satisfaction and scores in basic pattern analysis and try-on assessments, was selected as the prototype, and a research basic pattern reflecting strengths of each basic pattern was developed. In this study, a wedding dress basic pattern considering good fit and aesthetic for figures of Korean brides in their 20s was suggested. It is expected that the basic pattern will be used by continuously developing dress market and ready-made wedding dress manufacturers as well as in educational institutes.

Research Policy for National Competitiveness (성장잠재력 확충을 위한 기초연구 정책방향)

  • 송충한
    • Proceedings of the Korea Technology Innovation Society Conference
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    • 2003.05a
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    • pp.167-182
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    • 2003
  • Basic research is becoming more important in knowledge-based economy. In Korea, government's research policy has been enforcing applied research and development for economic growth rather than basic research. But, in 21st century, Korea's catch-up policy in science and technology arrived its limit. Without creative knowledge, we cannot expect national competitiveness. Therefore, we have to reform our research policy for national competitiveness. The directions are as follows; first, strengthening basic research, especially use-inspired basic research. Second, enlarging individual research program rather than group research program. Third, encouraging universities' specification through research grant review criteria. Fourth, beginning a new program for supporting regional universities' competitiveness.

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Thermal Behavior of Arrayed-Waveguide Grating Made of Silica/Polymer Hybrid Waveguide

  • Kim, Duk-Jun;Shin, Jang-Uk;Han, Young-Tak;Park, Sang-Ho;Park, Yun-Jung;Sung, Hee-Kyung;Kim, Dong-Kun
    • ETRI Journal
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    • v.26 no.6
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    • pp.661-664
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    • 2004
  • The thermal behavior of an arrayed-waveguide grating made of a silica/polymer hybrid waveguide was examined. We experimentally confirmed that the hybrid waveguide is effective to decrease the temperature and polarization dependence of the center wavelength owing to the negative thermo-optic coefficient of the refractive index and extremely low baking temperature of the polymer cladding. However, the detachment of the polymer cladding from the silica core, which took place either during a repeated heat cycle test or during long-term storage in atmosphere, was a serious problem for practical use.

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Performance Analysis for MPEG-4 Video Codec Based on On-Chip Network

  • Chang, June-Young;Kim, Won-Jong;Bae, Young-Hwan;Han, Jin-Ho;Cho, Han-Jin;Jung, Hee-Bum
    • ETRI Journal
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    • v.27 no.5
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    • pp.497-503
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    • 2005
  • In this paper, we present a performance analysis for an MPEG-4 video codec based on the on-chip network communication architecture. The existing on-chip buses of system-on-a-chip (SoC) have some limitation on data traffic bandwidth since a large number of silicon IPs share the bus. An on-chip network is introduced to solve the problem of on-chip buses, in which the concept of a computer network is applied to the communication architecture of SoC. We compared the performance of the MPEG-4 video codec based on the on-chip network and Advanced Micro-controller Bus Architecture (AMBA) on-chip bus. Experimental results show that the performance of the MPEG-4 video codec based on the on-chip network is improved over 50% compared to the design based on a multi-layer AMBA bus.

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