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Lead isotope measurement of geological reference materials using thermal ionization mass spectrometry (열이온화질량분석기를 이용한 암석표준시료에 대한 납 동위원소 분석)

  • Lee, Hyo Min;Jo, Hui Je;Kim, Taehoon
    • Analytical Science and Technology
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    • v.33 no.6
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    • pp.245-251
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    • 2020
  • Lead (Pb) has been shown to be a useful tracer of contamination sources and geochemical processes such as age dating and crustal evolution. These studies require a chromatographic technique for Pb separation from geological samples. This paper presents a comparison study on the effect of eluent concentration between 6M HCl and 8M HCl on the separation of Pb from Pb resin. The results showed that the separation of Pb using 6M HCl as the eluent was not effective compared to the separation using 8M HCl. To verify this method, we measured the Pb isotopic compositions of the Pb isotopic standard (NIST NBS981) and geological reference materials (BCR-2, GSP-2, and JG-1a) using a thermal ionization mass spectrometer (TIMS). The results correspond well with the reported values within the error range, implying that this method can be useful.

Effects of multi-layered active layers on solution-processed InZnO TFTs

  • Choi, Won Seok;Jung, Byung Jun;Kwon, Myoung Seok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2015.08a
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    • pp.204.1-204.1
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    • 2015
  • We studied the electrical properties and gate bias stress (GBS) stability of thin film transistors (TFTs) with multi-stacked InZnO layers. The InZnO TFTs were fabricated via solution process and the In:Zn molar ratio was 1:1. As the number of InZnO layers was increased, the mobility and the subthreshold swing (S.S) were improved, and the threshold voltage of TFT was reduced. The TFT with three-layered InZnO showed high mobility of $21.2cm^2/Vs$ and S.S of 0.54 V/decade compared the single-layered InZnO TFT with $4.6cm^2/Vs$ and 0.71 V/decade. The three-layered InZnO TFTs were relatively unstable under negative bias stress (NBS), but showed good stability under positive bias stress (PBS).

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Determination of Traces of Selenium in Plant Materials by Cathodic Stripping Voltammetry (Cathodic Stripping Voltammetry법에 의한 식물체 중 극미량 셀렌의 분석)

  • 문동철;홍성화;박만기;김중기;이광우
    • YAKHAK HOEJI
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    • v.29 no.3
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    • pp.144-151
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    • 1985
  • Cathodic stripping voltammetric determination of traces of selenium in plant samples was studied. Stripping peak of selenium (IV) from Cu-Se intermettalic deposit in acidic media containing copper (II) ion is specific, highly sensitive and well defined, is successfully used for the quantitative determination of selenuin down to the level of 1ng/ml. Sample is burnt in a calorimeter bomb under the oxygen pressure of 40atm. and the selenium is absorbed in 0.1M NaOH. After the solution is filtrated, concentrated and acidified with HCl, then passed through a column of cation exchange resin in the $H^{+}$ form(Dowex 50X-8). The column eluate is analyzed for selenium by differential pulse cathodic stripping voltammetric method. Analytical results of selenium for NBS SMR is well agreement with the certified values. Results are given for a series of plant materials.

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New Routing Header for Route Optimization in Mobile Networks (이동네트워크 환경에서 경로 최적화를 위한 새로운 라우팅 헤더)

  • Park, Jeong-Hoon;Choo, Hyun-Seung
    • Proceedings of the Korea Information Processing Society Conference
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    • 2007.05a
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    • pp.1276-1278
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    • 2007
  • 무선 네트워크 기술의 발전과 이동성 지원에 대한 사용자의 요구가 증대됨에 따라 모바일 IPv6와 이를 확장한 NEMO (NEtwork Mobility) Basic Support 프로토콜이 등장하였다. 이동네트워크들이 중첩되어 구성될 경우 NBS (NEMO Basic Support) 프로토콜을 사용하는 네트워크에서는 패킷이 네트워크를 구성하는 이동라우터(MR, Mobile Router)의 홈에이전트(HA, Home Agent)를 모두 거치면서 중첩 터널링이 수행되는 핀볼라우팅 문제가 발생한다. 본 논문에서는 이러한 문제점을 해결하기 위해 중첩된 이동네트워크에서 새로운 라우팅 헤더를 사용한 경로최적화 기법을 제안한다. 제안하는 기법은 새로운 IPv6 라우팅 헤더 DH (Destination-information Header)를 정의하고 이를 라우팅 헤더 타입 2를 대신하여 사용함으로써 중첩된 이동네트워크에서의 경로최적화를 구현한다. 이 기법은 기존 기법에 비하여 최적화된 경로로 통신하여 최소 32% 뛰어난 성능향상을 확인할 수 있다.

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A Measurement Study of a Dynamic Insulator Thermal Performance (동적 단열재의 열성능 측정에 관한 연구)

  • Ko, Seon-Mi;Kang, Eun-Chul;Lee, Euy-Joon
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.22 no.6
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    • pp.361-368
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    • 2010
  • Due to the insulation and the air-tightness requirement in modern buildings have resulted NBS(New Building Syndrome) and SBS(Sick Building Syndrome) of IAQ problems. Therefore, energy efficient way of solving such IAQ issues are of major concern in these days and building industries. This paper introduces a method to improve thermal performance with a DI(Dynamic Insulation) concept. The characteristic of the dynamic insulation is that the lower U-value as the higher air velocity through the DI in a micro level. A thermal performance monitoring study has been conducted to show the energy impact of porous DI over the static insulation material. The results show that up to 45% could be improved in the case with DI compared to the conventional insulation.

TDES CODER USING SSE2 TECHNOLOGY

  • Koo, In-Hoi;Kim, Tae-Hoon;Ahn, Sang-Il
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.114-117
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    • 2007
  • DES is an improvement of the algorithm Lucifer developed by IBM in the 1977. IBM, the National Security Agency (NSA) and the National Bureau of Standards (NBS now National Institute of Standards and Technology NIST) developed the DES algorithm. The DES has been extensively studied since its publication and is the most widely used symmetric algorithm in the world. But nowadays, Triple DES (TDES) is more widely used than DES especially in the application in case high level of data security is required. Even though TDES can be implemented based on standard algorithm, very high speed TDES codec performance is required to process when encrypted high resolution satellite image data is down-linked at high speed. In this paper, Intel SSE2 (Streaming SIMD (Single-Instruction Multiple-Data) Extensions 2 of Intel) is applied to TDES Decryption algorithm and proved its effectiveness in the processing time reduction by comparing the time consumed for two cases; original TDES Decryption and TDES Decryption with SSE2

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The Mechanisms for Thermal and Photochemical Isomerizations of N-Substituted 2-Halopyrroles: Syntheses of N-Substituted 3-Halopyrroles

  • Park, Sung-Hyun;Ha, Hong-Joo;Lim, Chul-Taek;Lim, Dong-Kwon;Lee, Kwang-Hee;Park, Yong-Tae
    • Bulletin of the Korean Chemical Society
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    • v.26 no.8
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    • pp.1190-1196
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    • 2005
  • Halopyrroles, N-substituted 2-halopyrroles were prepared by halogenation of N-substituted pyrroles with NBS, NCS, or surfuryl chloride. N-Substituted 3-halopyrroles were synthesized by acid-catalyzed thermal and photochemical isomerization reactions of N-substituted 2-halopyrroles. Both the thermal and photochemical reactions were acid-catalyzed. For the acid-catalyzed isomerization, a mechanism of [1,3] bromine shift followed by deprotonation is operated. For the acid-catalyzed photoisomerization, an excited triplet state of 2-protonated N-benzyl-2-halopyrrole produces an intermediate N-substituted pyrrole complex with halonium ion which is equilibrated with N-substituted pyrrole plus halonium ion, and then the halonium ion newly adds to 3-position of N-substituted pyrrole followed by deprotonation to afford N-benzyl-3-halopyrrole.

GC/MS analysis of volatile constituents from woody plants (목본성 식물의 휘발성 성분 GC/MS 분석)

  • Lee, Dong-Gu;Choi, Kyung;Lee, Sang-Hyun
    • Korean Journal of Agricultural Science
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    • v.38 no.4
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    • pp.723-730
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    • 2011
  • To search for the new development of industrial application of woody plants, the chemical composition of the volatile constituents from woody plants (Evodia daniellii, Clerodendron trichotomum, Prunus padus, and Zanthoxylum ailanthoides) was determined by GC and GC/MS spectrometric analysis with the aid of NBS, Wiley Library and RI indice searches. The major constituents were t-ocimene from the leaves of E. daniellii, linalool from the leaves of C. trichotomum, benzaldehyde from the leaves and twigs of P. padus, ${\beta}$-thujene from the leaves of Z. ailanthoides, and 2-undecanone from the stems of Z. ailanthoides. These results suggested that the major volatile constituents of woody plants could be a useful lead compound in the development of functional materials for industrial application.

The measurement of a discharging point using UHF Antenna with partial discharge in the model GIS (모의 GIS내에서의 부분방전시 UHF 안테나를 이용한 방전위치측정)

  • Jang, H.S.;Park, K.S.;Lee, H.C.;Kim, I.S.;Choi, B.J.;Choi, S.T.;Kim, K.C.;Lee, K.S.
    • Proceedings of the KIEE Conference
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    • 2003.07c
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    • pp.1806-1808
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    • 2003
  • 본 논문은 모의GIS(내에서 부분방전(partial discharge:PD) 발생 시 방사되는 전자파 신호를 두 개의 UHF(Ultra-High Frequency)타임 혼형안테나(Time-Do main Antennas: NBS-200)를 설계제작하여 오실로스코프를 이용한 부분방전의 위치검출에 관해 연구하였다. 실험조건은 GIS내에 금속 파티클을 넣고 전압을 32[kV]로 고정하여 파티클의 활발한 진동시에 방사되는 전자파 신호를 오실로스코프를 사용하여 측정된 두 신호의 시간차를 이용하여 추정하였다.

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Study on the development of Color Sensibility Scale and its application (색채 감정 척도의 개발과 활용에 관한 연구)

  • 황상민;김경인
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 1999.11a
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    • pp.295-301
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    • 1999
  • 본 연구에서는 특정 대상에 대한 사람들의 심리적인 색채반응을 측정할 수 있는 색채감성척도(PCS)를 개발하고 이것을 색채 감성 이미지의 평가에 어떻게 이용하는가를 보여주고자 한다. 색채심리에 기초한 색채감성척도(PCS)는 NCS와 ISCC-NBS 색명법에 의거한 색상과 톤의 개념으로 구성되었으며 기본형과 상세형의 두 가지가 개발 되었다. 표준화된 색채감성척도는 각 사람들마다 다르게 나타나는 색에 관한 이미지나 색에 대한 심리적인 선호반응을 객관적으로 측정할 수 있는 척도로 활용될 수 있다. 본 연구에서는 선호색, 선호의상색, 선호 화장품 색을 나타내는데 PCS가 어떻게 활용되는가를 보여주었다. PCS를 이용한 색채 감성 이미지는 Color Image Palette를 이용하여 각각의 특성을 비교할 수 있도록 제시되기도 하였다. 색채 경험에 대한 광학적이거나 물리적인 속성이 아닌 심리적인 특성을 평가하고 서로 다른 집단의 반응을 비교 평가하는데 PCS와 유용한 도구가 될 것이다.

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