• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2003.11a
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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.

• Progress in Superconductivity
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• v.13 no.1
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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.

• Journal of Magnetics
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• v.1 no.1
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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.

• Proceedings of the Botanical Society of Korea Conference
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• 2002.04a
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• pp.110-110
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• 2002

• IEMEK Journal of Embedded Systems and Applications
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• v.3 no.1
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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.

• Corrosion Science and Technology
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• v.5 no.5
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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.

• Macromolecular Research
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• v.16 no.4
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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.

• Annual Conference on Human and Language Technology
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• 2019.10a
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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.

• Preventive Nutrition and Food Science
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• v.10 no.1
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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.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.7
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• pp.2719-2726
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• 2010

The purpose of this study was to investigate the scientific basic grounds for the assessment of health and environmental diseases resulting from air pollutants in Pohang. For this study, we investigated pollutants, weather characteristics and concentration distribution of fine particles ($PM_10$) yearly and each season, using data from Air Quality Monitoring Stations. The properties of concentration distribution and seasonal fluctuation of $PM_10$ were studied qualitatively and quantitatively using CALPUFF, air dispersion model. The average concentration of $PM_10$ for each season was spring($75.7{\mu}g/m^3$)>summer($56.8{\mu}g/m^3$)>winter($53.6{\mu}g/m^3$)>fall( $52.7{\mu}g/m^3$). In the case of spring, high concentrations appear due to the Asian dust frequently occurring. The contributions of $PM_10$ classified by the types of pollution source in Pohang were point source 62%>mobile source 33%>area source 5%. An important point is that 97% of emissions were produced from the iron manufacture in steel industry. Therefore, it is necessary to control the emission sources of pollutants and to construct an observation system at Pohang steel industrial complex from now on. It’s time to control the risk factors for health and environmental disease to protect the health of resident in Pohang and its neighboring areas.