• 제목/요약/키워드: O.U.V

검색결과 395건 처리시간 0.028초

압전 MEMS 진동에너지 수집소자를 위한 졸겔 공법기반의 Pb(ZrTi)O3 박막의 특성 분석 및 평가 (Characterization of Sol-gel Coated Pb(ZrTi)O3 Thin film for Piezoelectric Vibration MEMS Energy Harvester)

  • 박종철;박재영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.1240_1241
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    • 2009
  • In this paper, sol-gel-spin coated $Pb(ZrTi)O_3$ thin film with $ZrO_2$ buffer-layer and $PbTiO_3$ seed-layer was investigated for vibration MEMS energy harvester to scavenge power from ambient vibration via d33 piezoelectric mode. Piezoelectric thin film deposition techniques on insulating layer is the important key for $d_{33}$ mode of piezoelectric vibration energy harvester. $ZrO_2$ buff-layer was utilized as an insulating layer. $PbTIO_3$ seed-layer was applied as an inter-layer between PZT and $ZrO_2$ layer to improve the crystalline of PZT thin film. The fabricated PZT thin film had a remanent polarization of 5.3uC/$cm^2$ and the coercive field of 60kV/cm. The fabricated energy harvester using PZT thin film with PTO seed-layer generated 1.1uW of electrical power to $2.2M{\Omega}$ of load with $4.4V_{pvp}$ from vibration of 0.39g at 528Hz.

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척도형용사의 의미적 불확정성에 대한 연구 (Semantische Unbestimmtheit der Skalaradjektiven)

  • 정동규
    • 한국독어학회지:독어학
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    • 제10집
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    • pp.277-296
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    • 2004
  • Ein sprachlicher Ausdruck ist in verschiedenen Situationen in einer Vielzahl unterschiedlicher Lesarten oder $Pr\"{a}zisierungen$ verwendbar, und zwar mil dom Grad an $Pr\"{a}zision$, der den jeweiligen kormmunikativen Erfordernissen angemessen ist. Sokommt Vagheit/$Ambiguit\"{a}t$ in sprachlichen Ausdrucken fast $durchg\"{a}ngig$ vol. In der vorliegenden Albeit wird die $M\"{o}glichkeit$ der semantischen $\"{U}bersetzung$ der Skalaradjektiven($gro{\ss}$, klein, $hei{\ss}$, kalt, schwer, leicht, schnell, langsam usw.) untersucht, die eigentlich die Vagheit als eine der konstitutiven Eigenschaften haben. Den Schwerpunkt $daf\"{u}r$ bildet die semantische Analyse $\"{u}ber$ die Graduierbarkeit und Vergleichbarkeit der Positivformen der Adjektiven, die vol allem M.J.Cresswell 1976 in seiner Albeit formuliert hat. V(pos) is the function $\eta$ in $D_{{\lll}{0,1}>,<{0,1}{\gg}.{\ll}{0,1,1},>,<{0.1}{\ggg}$ such that where ${\xi}{\in}D_{{\ll}{0,1,1},><{0,1}{\gg}$,$\eta({\xi})$ is the following function: For any ${\omega}{\in}D_{<0,1>$and a ${\in}D_1$ and w$\in$W, w${\in}{\eta}({\xi})({\omega})$(a) iff w ${\in}{\omega}$(a) and there is exactly one b such that ${\xi}({\omega})$(a,b); and for that b, b=$\gg$(for some > and u ${\in}{ \scr}{Z}(>))$ and u is toward the top of the scale determined by > when restricted to those v such that for some c, w${\in} {\xi}({\omega})$$(c,{\;} and w${\in}{\omega}(c)$. (Cresswell, 1976: 272) Obwohl sein Verfahren anhnd von dem semantischen Symbol eine methodische und theoretische $Ad\"{a}quatheit$ erf\"{u}llt$, bleibt der Vergleichwert noch unterspezifiziert. Fur die Behandlung dieser semantischen Unterspezifikation ist eine neue Semantik erforderlich, die den Wahrheitwert fur die $Zugeh\"{o}rigkeitsgrade$ der Skalaradjektive $einschlie{\ss}t$.

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SMALL DATA SCATTERING OF HARTREE TYPE FRACTIONAL SCHRÖDINGER EQUATIONS IN DIMENSION 2 AND 3

  • Cho, Yonggeun;Ozawa, Tohru
    • 대한수학회지
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    • 제55권2호
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    • pp.373-390
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    • 2018
  • In this paper we study the small-data scattering of the d dimensional fractional $Schr{\ddot{o}}dinger$ equations with d = 2, 3, $L{\acute{e}}vy$ index 1 < ${\alpha}$ < 2 and Hartree type nonlinearity $F(u)={\mu}({\mid}x{\mid}^{-{\gamma}}{\ast}{\mid}u{\mid}^2)u$ with max(${\alpha}$, ${\frac{2d}{2d-1}}$) < ${\gamma}{\leq}2$, ${\gamma}$ < d. This equation is scaling-critical in ${\dot{H}}^{s_c}$, $s_c={\frac{{\gamma}-{\alpha}}{2}}$. We show that the solution scatters in $H^{s,1}$ for any s > $s_c$, where $H^{s,1}$ is a space of Sobolev type taking in angular regularity with norm defined by ${\parallel}{\varphi}{\parallel}_{H^{s,1}}={\parallel}{\varphi}{\parallel}_{H^s}+{\parallel}{\nabla}_{{\mathbb{S}}{\varphi}}{\parallel}_{H^s}$. For this purpose we use the recently developed Strichartz estimate which is $L^2$-averaged on the unit sphere ${\mathbb{S}}^{d-1}$ and utilize $U^p-V^p$ space argument.

$TiO_2$의 첨가가 ZnO계 세라믹 바리스타에 미치는 전기적인 영향 (Influence of the Conduction Properties on ZnO-Based Ceramic Varistor with $TiO_2$ Additives)

  • 이상석;장경욱;이준웅
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1987년도 정기총회 및 창립40주년기념 학술대회 학회본부
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    • pp.234-238
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    • 1987
  • In this paper, the used specimen composition was added basic additives ($Bi_2O_3\;lmol%$, $Sb_2O_3\;lmol%$, CoO 0.5 mol%, MnO 0.5mol%) to ZnO powder, and $TiO_2$ (1,2,3,4 mol%) to the above basic composition. It appears that there are four regions of conduction current depended upon the strength of the applied electric field ; Ohimic region, Poole-Frenkel region, Schottky region and Tunneling region. Increasing of $TiO_2mol%$, the breakdown voltages of ZnO ceramic varistors are decreased. The decrease of breakdown voltages was explained with the decrease of potential barrier height. Moreover, V-I characteristics with temperature dependence are decreased with increasing of $TiO_2mol%$.

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코핀석(石)(Coffinite)의 화학조성(化學組成)에 관(關)한 연구(硏究) -미국(美國) 뉴멕시코주(州) 우드로광산산(鑛山産) 코핀석(石)을 중심(中心)으로- (Chemical composition of the Coffinite from the Woodrow Mine, New Mexico, U. S. A.)

  • 김수진
    • 자원환경지질
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    • 제11권4호
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    • pp.183-186
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    • 1978
  • Chemical analyses by electron microprobe indicate that the well-crystallized botryoidal coffinite with radial fibrous structure from the Woodrow Mine, New Mexico, U.S.A. has the formula ($U_{0.85}Ca_{0.14}$) $(Si_{0.86}P_{0.11}Al_{0.06}V_{0.02})O_2(OH)_4$, or ideally (U, Ca) (Si, P)$O_2(OH)_4$. It can be more simply designated as ideal formula $USiO_2(OH)_4$. This new formula is proposed for the coffinite.

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플라즈마 처리를 통한 Flexible ZnO nanowire 발전기 제작 및 효율향상 연구

  • 박성확;이경일;이철승;박지선;김선민;김성현;조진우
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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    • pp.424-424
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    • 2012
  • ZnO는 수열합성법을 통해 저온에서 단결정으로 성장할 수 있기 때문에 광전소자 및 압전소자로 응용되고 있으나, 성장된 ZnO nanowire 내부 산소 결함 및 표면에 OH기의 흡착에 의해 소자특성 저하를 발생시킨다. 본 연구에서는 ZnO의 결함의 최소화를 위해 Glass 기판에 수열합성법으로 성장된 ZnO nanowire를 ICP 플라즈마 장치를 이용하여 O2 25 sccm, Base Pressure $1.5{{\times}}10^{-3}$ Torr을 기준으로 파워와 시간에 따라 표면처리 하였다. 플라즈마 처리된 ZnO nanowire의 결함특성과 형상을 XPS와 FE-SEM를 통하여 분석하였으며, ZnO nanowire의 소자특성을 평가를 위해 Kapton Film/AZO/ZnO nanowire/PMMA/Au 구조의 발전기를 제작하였다. 150 W, 10 min에서 532.4 eV의 -OH결합이 최소화됨을 확인하였으며, 이를 이용하여 Flexible ZnO nanowire 발전기 제작 했을 경우 최대 Voltage 5 V, Current 156 nA 전기적 특성을 확인하였다.

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V-SUPER VERTEX OUT-MAGIC TOTAL LABELINGS OF DIGRAPHS

  • Devi, Guruvaiah Durga;Durga, Morekondan Subhash Raja;Marimuthu, Gurusamy Thevar
    • 대한수학회논문집
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    • 제32권2호
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    • pp.435-445
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    • 2017
  • Let D be a directed graph with p vertices and q arcs. A vertex out-magic total labeling is a bijection f from $V(D){\cup}A(D){\rightarrow}\{1,2,{\ldots},p+q\}$ with the property that for every $v{\in}V(D)$, $f(v)+\sum_{u{\in}O(v)}f((v,u))=k$, for some constant k. Such a labeling is called a V-super vertex out-magic total labeling (V-SVOMT labeling) if $f(V(D))=\{1,2,3,{\ldots},p\}$. A digraph D is called a V-super vertex out-magic total digraph (V-SVOMT digraph) if D admits a V-SVOMT labeling. In this paper, we provide a method to find the most vital nodes in a network by introducing the above labeling and we study the basic properties of such labelings for digraphs. In particular, we completely solve the problem of finding V-SVOMT labeling of generalized de Bruijn digraphs which are used in the interconnection network topologies.

The Reduction of Np(VI) by Acetohydroxamic Acid in Nitric Acid Solution

  • Chung, Dong-Yong;Lee, Eil-Hee
    • Bulletin of the Korean Chemical Society
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    • 제26권11호
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    • pp.1692-1694
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    • 2005
  • Spent nuclear fuel is reprocessed commercially by the chemical process to recover U and Pu. Recently, new salt-free reagents to separate plutonium and neptunium from uranium suitable for use in a single cycle flowsheet have been developed. Acetohydroxamic acid $(CH_3CONHOH)$ has been taken much interest in as a complexing agent capable of selective stripping of tetravalent actinides from U(VI) when actinides are present in the solvent stream of the advanced PUREX process. Additionally acetohydroxamic acid will rapidly reduce Np(VI) to inextractable Np(V) thus allowing the separation of Np from U. In this study, the rate equation for the reduction of Np(VI) to Np(V) in nitric acid aqueous solution has been determined as: $-[NpO_2^{2+}]$/dt = $k[NpO_2^{2+}]$[AHA] with k = 191.2 ${\pm}$ 11.2 $M^{-1}s^{-1}$ at 25 ${\pm}$ 0.5 ${^{\circ}C}$ and $[HNO_3]$ = 1.0 M. Comparison with other reductants available in the literature, acetohydroxamic acid is a strong one for $NpO_2^{2+}$.

4-Nitroazoxybenzene 에 關한 硏究 (第1報) 4-Nitroazoxybenzene 의 $\{alpha}$- 및 ${\beta}$- 異性體의 分離와 U.V. Spectrophotometry에 의한 그 構造硏究 (Study of 4-Nitroazoxybenzenes (Part Ⅰ) Separation of the Isomers of 4-Nitroazoxybenzenes and their Structure Study by U.V. Spectrophotometry)

  • 한치선;윤병희;이혁구
    • 대한화학회지
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    • 제7권3호
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    • pp.197-202
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    • 1963
  • The ${\alpha}-and\;{\beta}$-isomer of 4-nitroazoxybenzenes have been separated by liquid chromatography and their U.V. spectra were examined. The n${\to}{\pi}^{\ast}$ transition band of the compounds did not appear, likewise the cases of other compounds of the series. Transition band of the new isomer were as usual as those of other azoxy-compounds, whereas the ${\pi}{\to}{\pi}^{\ast}$ transition band of the other isomer which is reported in the literature shown peculier hypochromic shift and hypochromic effect. From the spectroscopic point of view it is very likely that the new isomer (m.p. $184-5^{\circ}C$) is ${\alpha}$-isomer and the other one (m.p. $152^{circ}C$) is ${\beta}$-isomer contrary to the literature.

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