• 제목/요약/키워드: U/F

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핵연료분말 제조공정에서 발생된 여액으로부터 우라늄 회수 및 회수된 우라늄 화합물의 열분해 특성 (Uranium Recovery from Nuclear Fuel Powder Conversion Plant Filtrate and its Thermal Decomposition Characteristics)

  • 정경채;정지영;김병호;김태준;최종현
    • 한국세라믹학회지
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    • 제39권2호
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    • pp.204-209
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    • 2002
  • 본 연구에서는 AUC 공정에서 발생되는 액체폐기물에 미량 함유되어 있는 우라늄을 회수/재사용하기 위해 액상에서 침전법을 이용하여 용해도가 작은 우라늄화합물을 얻었으며, 이 화합물에 대한 chemical analysis, thermal analysis, x-ray diffraction analysis 및 FT-IR 분석을 통해 물성 특성을 해석하였다. 연구결과, 화학분석 및 FT-IR 분석으로부터 우라늄화합물은 $UO_4{\cdot}2NH_4F$ 형태를 가지고 있음을 알 수 있었으며, 평균 2∼3${\mu}m$ 입자 크기를 갖는 hexagonal 형태를 나타내었다. 열 분해시 분해 온도에 따라 중간물질로 $UO_4F,\;UO_4,\;UO_3,\;U_3O_8$ 등으로 변환되었으며, 상온에서 800$^{\circ}C$까지의 공기분위기에서 일정한 가열속도로 열분해시킬 경우, $UO_4{\cdot}2NH_4F{\rightarrow}UO_4F{\rightarrow}UO_4{\rightarrow}UO_3{\rightarrow}U_3O_8$의 반응 메커니즘을 나타내었다.

급냉응고법으로 제조한 Zr-Ni-Cu-Al-Ti 합금의 열적, 기계적 성질 (Thermal and Mechanical Properties of Rapidly Solidified Zr-Ni-Cu-Al-Ti Alloy)

  • 최익석;한태교;지용권;임병문;김영환;김인배
    • 한국재료학회지
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    • 제11권3호
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    • pp.171-177
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    • 2001
  • 급냉응고방식으로 제조한 비정질 Z $r_{62-x}$N $i_{10}$C $u_{20}$A $l_{8}$ $Ti_{x}$ (x=3, 6, 9at%) 합금을 사용하여 열적, 기계적 성질을 조사하였다. 시효온도에 따른 결정화 거동은 Ti 3at%에서는 비정질$\longrightarrow$비정질+Z $r_2$A $l_3$+Zr+(Ni,Ti)$\longrightarrow$Z $r_2$Cu+Al+(Ni,Ti)의 결정화 거동을 나타내었으며, Ti 6at%에서는 비정질$\longrightarrow$비정질+Al$\longrightarrow$A $l_2$Ti+NiZr+CuTi, Ti 9at%에서는 비정질$\longrightarrow$비정질+Zr+Al$\longrightarrow$Zr+A $l_2$Zr+Al $Ti_3$+CuTi의 결정화 거동을 보였다. 시효온도가 증가할수록 비정질 모상에 석출상의 체적율( $V_{f}$ )이 증가하고 그에 따라 비커스 경도 ( $H_{v}$ )간이 증가하였다. 파괴인장강도($\sigma_{f}$ )는 $V_{f}$ 의 증가에 따라 증가하다가 Z $r_{59}$A $l_{10}$N $i_{20}$C $u_{8}$ $Ti_3$$V_{f}$ =38%에서 1219MPa의 최대값을 보이고, Z $r_{56}$A $l_{10}$N $i_{20}$C $u_{8}$ $Ti_{6}$$V_{f}$ =2%에서 1203MPa의 최대값을 보이고, Z $r_{53}$A $l_{10}$N $i_{20}$C $u_{8}$ $Ti_{9}$ $V_{f}$ =5%에서 1350MPa의 최대값을 나타낸 후 그 이상의 $V_{f}$ 에서는 급격히 감소하였다. $\sigma_{f}$ 가 급격히 감소하는 $V_{f}$ 와 연성 파면에서 취성파면으로 천이되는 $V_{f}$ 가 일치하였다.f/가 일치하였다.

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감탄사를 수반한 독일인 신체언어 읽기 (Das Verstehen der deutschen $K\"{o}rpersprache$ mit Interjektionen)

  • 김영순
    • 한국독어학회지:독어학
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    • 제2집
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    • pp.285-306
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    • 2000
  • In der vorliegenden Arbeit wurde die Auffassung motiviert, dass es sich bei der deutschen $K\"{o}rpersprache$ in semiotischer Hinsicht um kommunikative Geste handelt. Die semio-syntaktischen, -semantischen und -pragmatischen Charakteristika dieser Geste wurden erortert. Insbesondere die ermittelten syntaktischen und semantischen Eigenschaften der $K\"{o}rpersprache\;sprechen\;f\"{u}r$ die Auffassung, dass sie in semio-syntaktischer, -semantischer und -pragmatischer Hinsicht mit Interjektionen $verkn\"{u}pfen\;k\"{o}nnen$. Beispielsweise wurde eine deutsche Geste 'Telefone handhaben' $angef\"{u}hrt$. Bei dieser Geste tritt eine deutsche vokalische Interjektion 'Klingeling' auf. Diese Geste stellt drei Ausdrucksvariationen(1- 3) und vier Bedeutungsvaritionen(A-D) dar: 1) Die Faust neben das Ohr halten, 2) Daumen neben das Ohr und Kleinfinger neb en den Mund halten und 3) Mit dem Zeigefinger var dem $K\"{o}rper$ frontal kreisen; A) Telefonieren thematisieren, B) Einen Telefonanruf aufforden, C) Zu einen Telefonanruf aufforden und D) Den Eingang eines Anrufs an zeigen. Mit Hilfe der semiotischen Gestenanalyse $k\"{o}nnen$ die deutschen $K\"{o}rpersprache$ mit Interjektionen alphabetisch geordnet werden, und die Gestenliste soll $f\"{u}r$ den DaF-Unterricht von Nutzen sein.

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EXISTENCE AND UNIQUENESS OF POSITIVE SOLUTIONS FOR A CLASS OF SEMIPOSITONE QUASILINEAR ELLIPTIC SYSTEMS WITH DIRICHLET BOUNDARY VALUE PROBLEMS

  • CUI, ZHOUJIN;YANG, ZUODONG;ZHANG, RUI
    • Journal of applied mathematics & informatics
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    • 제28권1_2호
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    • pp.163-173
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    • 2010
  • We consider the system $$\{{{-{\Delta}_pu\;=\;{\lambda}f(\upsilon),\;\;\;x\;{\in}\;{\Omega}, \atop -{\Delta}_q{\upsilon}\;=\;{\mu}g(u),\;\;\;x\;{\in}\;{\Omega},} \atop u\;=\;\upsilon\;=\;0,\;\;\;x\;{\in}\;{\partial\Omega},}$$ where ${\Delta}_pu\;=\;div(|{\nabla}_u|^{p-2}{\nabla}_u)$, ${\Delta}_{q{\upsilon}}\;=\;div(|{\nabla}_{\upsilon}|^{q-2}{\nabla}_{\upsilon})$, p, $q\;{\geq}\;2$, $\Omega$ is a ball in $\mathbf{R}^N$ with a smooth boundary $\partial\Omega$, $N\;{\geq}\;1$, $\lambda$, $\mu$ are positive parameters, and f, g are smooth functions that are negative at the origin and f(x) ~ $x^m$ g(x) ~ $x^n$ for x large for some m, $n\;{\geq}\;0$ with mn < (p - 1)(q - 1). We establish the existence and uniqueness of positive radial solutions when the parameters $\lambda$ and $\mu$ are large.

Variation in Fucoidan Contents and Monosaccharide Compositions of Korean Undaria pinnatifida (Harvey) Suringar (Phaeophyta)

  • 이유경;임동정;이윤희;박용일
    • ALGAE
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    • 제21권1호
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    • pp.157-160
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    • 2006
  • Three different forms of Undaria pinnatifida, the southern form (U. pinnatifida f. typica), the northern form (U. pinnatifida f. distans), and Samcheok form (recently cultivated strain), were examined for the contents and compositions of fucoidans. Fucoidans were extracted from the dried edible portions of three forms of U. pinnatifida in low pH condition, mainly by ethanol precipitation and CaCl2 treatment. It was shown that Samcheok form contains 1.8 and 3.5 times more fucoidans than the northern and the southern forms, respectively. The monosaccharide compositions of individual fucoidans were also varied. The fucoidans from the southern and the northern forms were shown to be composed of mainly fucose and galactose with the molar percentage ratios of 83.5%:16.5% and 87.4%:12.6%, respectively, indicating that these are F-type fucoidans. The fucoidan from Samcheok form, however, consisted of fucose (62.7%), galactose (32.9%), and small amount of glucose (4.4%). The results of this study showed that both amount and monosaccharide compositions of fucoidans are variable depending on U. pinnatifida forms.

A.c.I.-구문에서의 대명사 분포에 관한 연구 (Distribution von Pronomina in A.cI.-Konstruktionen)

  • 김연찬
    • 한국독어학회지:독어학
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    • 제7집
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    • pp.105-125
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    • 2003
  • Personal- und Reflexivpronomen stehen in einer komplementaren Beziehung zueinander. Die vorliegende Arbeit zeigt, welches von beiden Pronomen verschiedenen AcI-Konstruktionen jeweils richtig ist Vor allem stelle ich hier die These auf, dass Grammatik in erster Linie ein Regelwerk ist und dass dernzufolge $S\"{a}tze$ mit gleicher Struktur immer einheitlich und konsistent mit denselben Regeln $erkl\"{a}rt$ werden sollten: (1) a. Der Gefangen $l\"{a}sst$ den Polizisten auf ${\ast}sich_i/ihn_i$ achten. b. $Hans_i{\;}l\"{a}sst$ Maria zu $sich_i/{\ast}ihm_i$ kommen. (2) a. $Peter_i$ sieht Hans von ${\ast}sich_i/ihm_i$ betrogen. b. $Hans_i{\;}f\"{u}hlt$ die Freundin von $sich_i/{\ast}ihm_i$ weggezogen. Bei diesen Beispielen liegt der Verteilungsunterschied der Pronomina nicht an Grammatikregeln sondern am individuellen Sprachgebrauch. Ferner wird hier darauf hingewiesen, dass die AcI-Verben mit Ausnahme des Verbs lassen a1s 3-wertige Verben so wie die $S\"{a}tze$ in Beispiel (3) zu behandein sind D.h., die Struktur $f\"{u}r$ AcI-Konstruktionen sieht so aus wie (4b), nicht wie (4a). Betrachten wir dies noch einmal an einem Beispiel: (3) a. Ich sehe mich $m\"{u}de$ b. Ich $f\"{u}hle$ mich viel besser.

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독일어에서 음운단어 (Phonologisches Wort im Deutschen)

  • 유시택
    • 한국독어학회지:독어학
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    • 제8집
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    • pp.1-23
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    • 2003
  • Im Deutschen wird generell einem Suffix zwei verschiedene prosodische Strukturen zugewiesen: ein konsonanteninitiales Suffix bildet sein eigenes phonologisches Wort, ein vokalinitiales Suffix dagegen nicht. $F\"{u}r$ diese Unterscheidung zwischen zwei Suffixklassen nennt man innerhalb einer regelbasierten Theorie zwei Kriterien: (i) Phonologisches Wort fungiert als $Dom\"{a}ne{\;}f\"{u}r$ die Silbifizierung und die Koordinationsreduktion, (ii) Konsonanteninitiale Suffixe $tr\"{a}gen$ einen Nebenakzent, $w\"{a}hrend$ einem vokalinitialen Suffix kein Akzent zugewiesen wird. Diese Arbeit zeigt, dass das erste Kriterium kein Argument $f\"{u}r$ die Annahme eines phonologischen Wortes ist. Die Existenz eines phonologischen Wortes und die Unterscheidung zwischen zwei Suffixklassen hinsichtlich des prosodischen Status werden durch einen Zirkelschluss $begr\"{u}ndet$, indem die Annahme eines phonologischen Wortes $Ph\"{a}nomene$ wie Silbifizierung und Koordinationsreduktion rechtfertigt, diese $Ph\'{a}nomene$ wiederum ihrerseits die Annahme eines phonologischen Wortes. Die hier vorgeschlagene Constraintsinteraktion erfasst dagegen den wesentlichen Charakter der beiden $Ph\"{a}nomene$, ohne dabei einen direkten Bezug auf das phonologische Wort zu nehrnen. Auch im Zusammenhang mit dem zweiten Kriterium stellt sich heraus, dass es keinen Grund gibt, Akzentunterschiede bei Suffixen anzunehmen. Die Allomorphie der Superlativ-Suffixe +est/+st ergibt sich aus dem Constraintranking OCP$\gg$ $fu{\ss}bezogene$ Constraints, nicht aus dem Akzentunterschied zwischen Suffixen.

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군용 SBC에서의 고속메모리모듈의 I/F 적용연구 (DDR Memory I/F Implementation For Military Single Board Computer)

  • 이특수;김영길
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2010년도 춘계학술대회
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    • pp.540-543
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    • 2010
  • 군용 SBC에 주로 사용되는 중앙 처리 장치(Central Processing Unit)는 주로 Power PC의 계열이며 Freescale사의 G4 계열인 74xx 프로세서가 주로 사용된다. 이러한 CPU인 7447A는 System Controller를 통하여 SBC 내의 주 기억 장치와 통신을 한다. 본 논문에서는 위와 같은 SBC의 구조에서 System Controller와 DDR 메모리 소자 간 I/F를 구현함에 있어 PCB적층 구조, 소자들의 Layout, 임피던스매칭과 Rugged 환경 Level에서 적용 되는 군 환경에서 동작 가능한 DDR 메모리를 모듈로 설계하여 구현하였다. 또한, 군용환경에 적용하기위한 SBC의 형상은 주로 6U, 3U의 표준 형태로 설계되어져야 한다.

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/오/-/우/ 합성모음 연속체에 대한 중국인 한국어 학습자의 청지각적 경계 (Perceptual Boundary on a Synthesized Korean Vowel /o/-/u/ Continuum by Chinese Learners of Korean Language)

  • 윤지현;김은경;성철재
    • 말소리와 음성과학
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    • 제7권4호
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    • pp.111-121
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    • 2015
  • The present study examines the auditory boundary between Korean /o/ and /u/ on a synthesized vowel continuum by Chinese learners of Korean language. Preceding researches reported that the Chinese learners have difficulty pronouncing Korean monophthongs /o/ and /u/. In this experiment, a nine-step continuum was resynthesized using Praat from a vowel token from a recording of a male announcer who produced it in isolated form. F1 and F2 were synchronously shifted in equal steps in qtone (quarter tone), while F3 and F4 values were held constant for the entire stimuli. A forced choice identification task was performed by the advanced learners who speak Mandarin Chinese as their native language. Their experiment data were compared to a Korean native group. ROC (Receiver Operating Characteristic) analysis and logistic regression were performed to estimate the perceptual boundary. The result indicated the learner group has a different auditory criterion on the continuum from the Korean native group. This suggests that more importance should be placed on hearing and listening training in order to acquire the phoneme categories of the two vowels.

Effects of NaF evaporation rate on the properties of $CuInSe_2$ thin-film solar cells

  • 박순용;이은우;이상환;박상욱;정우진;김우남;전찬욱
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2010년도 춘계학술발표대회
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    • pp.36.2-36.2
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    • 2010
  • A small amount of Na incorporated in $CuInSe_2$ (CIS) absorption layer has become widely accepted as a requirement for efficient polycrystalline CIS solar cells. However, there is ongoing argument on the role of sodium incorporated in the absorber. In this paper, CIS absorption layers have been deposited using the three-stage co-evaporation process on Mo coated non-Alkali glass substrates. The NaF was evaporated during the second-stage with various fluxes. This paper is focusing on differences of micro-structure and composition ratio of the absorber realized with different Na contents and the variation of electrical properties of the cells with the corresponding absorbers. The analytical results of x-ray diffraction (XRD) patterns, field emission scanning electron microscope (FE-SEM), energy dispersive spectroscopy (EDS) and current-voltage characteristics will be discussed to investigate the effect of NaF flux on the CIS absorber formation and its cell performance.

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