• 제목/요약/키워드: Pohang Korea

검색결과 1,645건 처리시간 0.029초

PDP TV Screen Filter의 Shielding Effectiveness 측정 및 분석 (Measurements and Analysis of Electromagnetic Shielding Effectiveness of PDP TV Screen Filters)

  • 박규복;김윤정;김영수
    • 한국전자파학회:학술대회논문집
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    • 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
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    • pp.47-53
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    • 2003
  • Screen filter of PDP TV plays an important role in satisfying the EMI/EMC specifications. Two types of filters, the mesh type and the sputter type, are used in PDP TVs, and this paper presents measurement results of the shielding effectiveness (SE) in the frequency range from 50MHz to 1GHz. Two methods were used for the measurement, one using network analyzer (NA) in an open area test site(OATS), and the other using the screen room. The overall conclusion is that the shielding effectiveness of the screen filter is related to the surface resistance of the screen filter. The mesh type screen filters are superior to the sputter types in the shielding effectiveness, which is varying with the frequency.

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그래핀 조셉슨 접합에서 초전류의 게이트 전압 의존성 (Gate-tunable Supercurrent in Graphene-based Josephson Junction)

  • 정동찬;이길호;도용주;이후종
    • Progress in Superconductivity
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    • 제13권1호
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    • pp.47-51
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    • 2011
  • Mono-atomic-layer graphene is an interesting system for studying the relativistic carrier transport arising from a linear energy-momentum dispersion relation. An easy control of the carrier density in graphene by applying an external gate field makes the system even more useful. In this study, we measured the Josephson current in a device consisting of mono-layer graphene sheet sandwiched between two closely spaced (~300 nm) aluminum superconducting electrodes. Gate dependence of the supercurrent in graphene Josephson junction follows the gate dependence of the normal-state conductance. The gate-tunable and relatively large supercurrent in a graphene Josephson junction would facilitate our understanding on the weak-link behavior in a superconducting-normal metal-superconducting (SNS) type Josephson junction.

Electronic Structures and Magnetic Properties of Fe/Si/Fe Trilayer

  • Park, Jin-Ho;Youn, Suk-Ju;Min, Byung-Il;Yi, Jae-Yel
    • Journal of Magnetics
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    • 제1권1호
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    • pp.4-8
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    • 1996
  • Employing the LMTO band method, we have studied electronic and magnetic properties of Fe/Si/Fe trilayer in which the z-direction is chosen to be (111) direction of FeSi with B2 phase, We have also determined electronic structure of bulk FeSi, as a reference material. The ground state of FeSi is paramagnetic insulator with a band gap of 0.05 eV. Band structures of Fe/Si/Fe with varying the thickness of the spacer layer reveal that the spacer layer is metallic, and the states along the growth direction do not disperse much reflecting a two-dimensional nature. Magnetic moment of Fe atom in the interfacial layer of Fe/Si/Fe is reduced a lot as compared to the bulk value, suggesting a strong hybridization between Fe and Si states. The geometry of the Fermi surface indicates that the magnetic coupling period of ~8ML (monolayers) in Fe/Si/Fe is explained with a short Fermi wave vector of bcc Si.

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리눅스 환경에서 WIPI를 지원하기 위한 HAL (Handset Abstraction Layer) 이식 (Poring of WIPI HAL in Embedded Linux)

  • 박우람;김태웅;박찬익
    • 대한임베디드공학회논문지
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    • 제3권1호
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    • pp.30-33
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    • 2008
  • This paper persents how to port HAL (Handset Abstraction Layer) on embedded Linux to support WIPI (Wireless Internet Platform for Interoperability). As smart phones are widespread nowdays, the operating system is changing from a simple kernel like Qualcomm REX OS to more feature-rich Linux kernel. For this reason, we investigate the internal structure of HAL on REX OS and design how to port it to embedded Linux. Careful analysis leads us to identify several porting issues such as thread support, graphical user interface. In addition, we describe some problems discovered during the implementation process and propose alternative architecture of HAL for WIPI on Linux.

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Development of Metallic Bipolar Plate Material with W-addition in Austenitic Stainless Steel for PEMFC Environment

  • Kim, Kwang Min;Koh, Sung Ung;Kim, Kyoo Young
    • Corrosion Science and Technology
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    • 제5권5호
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    • pp.153-159
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    • 2006
  • Austenitic stainless steels with addition of various amounts of Mo and W were evaluated in terms of corrosion and contact resistance to determine optimum alloy composition of metallic bipolar plate for PEMFC. The corrosion property was evaluated by both acid fume exposure test at $130^{\circ}C$ and by electrochemical polarization tests in $H_3PO_4$ solution at $80^{\circ}C$. Austenitic stainless steel with proper amount of Mo and W demonstrated not only good corrosion resistance but also low contact resistance. Analyses on the passive film show that partial substitution of Mo by W enhances passive film stability and repassivation property. Test results suggest that austenitic stainless steel with 2 wt%Mo and 4 wt%W has optimum composition for metallic bipolar plate used in PEMFC.

Self-Assembled Block Copolymers: Bulk to Thin Film

  • Kim, Jin-Kon;Lee, Jeong-In;Lee, Dong-Hyun
    • Macromolecular Research
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    • 제16권4호
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    • pp.267-292
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    • 2008
  • Block copolymers that two or more polymer chains are covalently linked have drawn much attention due to self-assembly into nanometer-sized morphology such as lamellae, cylinders, spheres, and gyroids. In this article, we first summarize the phase behavior of block copolymers in bulk and thin films and some applications for new functional nanomaterials. Then, future perspectives on block copolymers are described.

본문-질의 비교를 활용한 오답 질의 분류 (Incorrect query classification via context-query comparison)

  • 한상도;유환조;이근배;맹성현
    • 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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    • 한국정보과학회언어공학연구회 2019년도 제31회 한글 및 한국어 정보처리 학술대회
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    • pp.440-442
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    • 2019
  • 본 논문은 딥 러닝 기반의 독해 기술이 풀지 못하는 문제를 분류해내는 기술에 관한 것이다. 해당 연구에서는 독해 데이터 및 시스템 결과 분석을 통해 시스템이 풀지 못하는 문제들의 특징을 도출해내고, 이에 알맞은 전략들을 시도해 보았다. 분석 결과에 따른 시도들은 각 목적에 부합하는 결과를 나타냈으며, 특히 독해 기술의 특징에 기반한 방법론이 효과적이었다. 본 논문에서 제안하는 방법은 본문과 질의 간 유사도 행렬을 활용하는 것으로, 기존의 독해 기술이 본문과 질의의 유사도를 활용하여 정답을 내는 것에 영감을 얻었다.

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Correlation between Serum Leptin Levels and BMI in Adults Residing in Pohang, Korea

  • Shin, Hyeon-Soo;Crabtree, Jennifer;Rayner, Vernon;Trayhurn, Paul;Do, Myoung-Sool
    • Preventive Nutrition and Food Science
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    • 제10권1호
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    • pp.64-67
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    • 2005
  • Leptin is a small polypeptide hormone secreted primarily by adipocytes. Leptin regulates energy balance by decreasing food intake and increasing energy expenditure. This study investigated the relationships between serum leptin levels and BMI (body mass index) in 49 adults in Pohang, Korea. The subjects were 25 males and 24 females, aged 21 to 64 years attending an outpatient clinic at Handong University Sunlin Presbyterian Hospital. Values are given +/- the standard error of the mean. Our study shows that the serum leptin levels in these subjects were positively correlated with BMI. The leptin levels were higher in females (2.39+/-1.82 ng/mL) than in males (0.43+/-0.455ng/mL), although lower than previously reported. We therefore compared the serum leptin levels from the male Korean subjects (BMI 24.3+/-0.74㎏/㎡) with serum from six British males with a similar BMI (23.4+/-1.48㎏/㎡). The serum leptin concentrations (1.76+/-0.76 ng/mL) were lower than that of plasma (4.28+/-1.66 ng/mL) in the British subjects. The serum leptin in the British subjects (1.76+/-0.76ng/mL) was higher than that in the Koreans. There was no correlation between leptin levels and BMI in either male (slope 0.018 ± 0.036, p=0.624) or female (slope 0.382±0.433, p=0.417) type 2 diabetic patients in Pohang, Korea. Taken together, our study shows that the serum leptin level in Koreans varies with the BMI, but is lower than that of BMI-matched British subjects.

포항지역 오염물질 보건.환경 위해성 평가 -미세먼지의 발생특성 및 농도분포를 중심으로- (Health and Environmental Risk Assessment of Pollutants in Pohang)

  • 정종현;최원준;임헌호;손병현
    • 한국산학기술학회논문지
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    • 제11권7호
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    • pp.2719-2726
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    • 2010
  • 본 연구는 포항지역 환경오염물질의 보건 환경 위해성 평가를 위한 기초연구의 일환이며, 이를 위하여 포항시에 소재한 지역대기자동측정 자료를 이용하여 연별, 계절별 $PM_10$ 농도분포에 대한 현황, 기상특성 및 오염물질 농도분포 분석을 수행하였고, 대기확산 모델(CALPUFF)을 이용하여 농도분포 특성에 대해 정성적, 정량적으로 확인하였다. 포항지역의 $PM_10$ 농도분포를 확인한 결과, 포항지역의 계절별 $PM_10$ 평균농도는 봄($75.7{\mu}g/m^3$)>여름($56.8{\mu}g/m^3$)>겨울($53.6{\mu}g/m^3$) >가을($52.7{\mu}g/m^3$) 순으로 봄에는 빈번히 발생하는 황사의 영향으로 높은 농도를 나타내었다. 포항지역 오염원별 $PM_10$ 배출량은 점오염원 62%>이동오염원 33%>면오염원 5% 순이며, 점오염원 중 전체 97%가 철강산업인 제철제강업에서 발생되었다. 포항지역은 $PM_10$의 영향을 많이 받고 있는 지역으로 포항철강공단지역에 대한 환경오염물질 원인배출원에 대한 감시체계의 보완 및 집중관리와 함께 포항지역 주민의 건강 보호를 위하여 보건 및 환경에 악영향을 미치는 위해인자 및 오염물질을 원천적으로 차단하는 작업이 지속적으로 수행되어야 할 시점이다.