• 제목/요약/키워드: E.A.V.

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Electron-excitation Temperature with the Relative Optical-spectrumIntensity in an Atmospheric-pressure Ar-plasma Jet

  • Han, Gookhee;Cho, Guangsup
    • Applied Science and Convergence Technology
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    • 제26권6호
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    • pp.201-207
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    • 2017
  • An electron-excited temperature ($T_{ex}$) is not determined by the Boltzmann plots only with the spectral data of $4p{\rightarrow}4s$ in an Ar-plasma jet operated with a low frequency of several tens of kHz and the low voltage of a few kV, while $T_{ex}$ can be obtained at least with the presence of a high energy-level transition ($5p{\rightarrow}4s$) in the high-voltage operation of 8 kV. The optical intensities of most spectra that are measured according to the voltage and the measuring position of the plasma column increase or decay exponentially at the same rate as that of the intensity variation; therefore, the excitation temperature is estimated by comparing the relative optical-intensity to that of a high voltage. In the low-voltage range of an Ar-jet operation, the electron-excitation temperature is estimated as being from 0.61 eV to 0.67 eV, and the corresponding radical density of the Ar-4p state is in the order of $10^{10}{\sim}10^{11}cm^{-3}$. The variation of the excitation temperature is almost linear in relation to the operation voltage and the position of the plasma plume, meaning that the variation rates of the electron-excitation temperature are 0.03 eV/kV for the voltage and 0.075 eV/cm along the plasma plume.

46-MeV 전자선형가속기의 TOF 방법을 이용한 탄탈의 중성자 공명 에너지 분석에 관한 연구 (A Study on Neutron Resonance Energy of Tantalum by 46-MeV Electron Linac TOF Method)

  • 이삼열
    • 한국방사선학회논문지
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    • 제7권3호
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    • pp.245-249
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    • 2013
  • 천연 탄탈의 중성자포획에 의한 공명에너지를 측정하기 위하여 교토대학의 원자로연구소의 46-MeV 전자선형가속기의 광핵반응에서 발생하는 중성자를 이용하였다. 중성자포획에서 발생되는 즉발감마선을 BGO($Bi_4Ge_3O_{12}$)섬광검출장치로 측정하였다. 검출장치는 탄탈 시료에서 발생되는 즉발감마선을 기하학적으로 모두 측정하도록 만들어져 있으며 측정되어진 전기적 신호를 탄탈의 중성자 공명에너지 동정하는 스펙트럼구성에 사용하였다. 연구에서 사용되어진 중성자의 에너지는 1 ~ 200 eV 영역에 대하여 각각의 공명에너지를 분석하였다. 중성자에너지 측정은 중성자 비행시간법(TOF: Time-of-Flight)을 통하여 측정하였다. 광핵반응을 통한 중성자발생에서는 고에너지영역에서 강한 제동복사선이 발생하므로 수 keV영역 이하 영역의 중성자에너지에 대해서만 중성자공명을 측정하였다. 얻어진 Ta에 대한 중성자 포획 공명에너지 측정결과는 이전의 실험에 의한 측정 결과들 및 ENDF/B-VI와 Mughabghab의 평가된 값들과 비교 및 검토를 하였다. 측정되어진 공명들은 4.28 eV에서 거대 공명들을 측정하였고 그 이상의 에너지 영역의 다른 공명들도 이론에 의해서 계산되어진 값들과 비교하였다. 144.3 eV를 제외한 공명들은 평가값들과 거의 일치하는 경향을 보였다.

Climate and Human coronaviruses 229E and Human coronaviruses OC43 Infections: Respiratory Viral Infections Prevalence in Hospitalized Children in Cheonan, Korea

  • Kim, Jang Mook;Jeon, Jae Sik;Kim, Jae Kyung
    • Journal of Microbiology and Biotechnology
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    • 제30권10호
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    • pp.1495-1499
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    • 2020
  • The study of climate and respiratory viral infections using big data may enable the recognition and interpretation of relationships between disease occurrence and climatic variables. In this study, real-time reverse transcription quantitative PCR (qPCR) methods were used to identify Human respiratory coronaviruses (HCoV). infections in patients below 10 years of age with respiratory infections who visited Dankook University Hospital in Cheonan, South Korea, from January 1, 2012, to December 31, 2018. Out of the 9010 patients who underwent respiratory virus real-time reverse transcription qPCR test, 364 tested positive for HCoV infections. Among these 364 patients, 72.8% (n = 265) were below 10 years of age. Data regarding the frequency of infections was used to uncover the seasonal pattern of the two viral strains, which was then compared with local meteorological data for the same time period. HCoV-229E and HCoV-OC43 showed high infection rates in patients below 10 years of age. There was a negative relationship between HCoV-229E and HCoV-OC43 infections with air temperature and wind-chill temperatures. Both HCoV-229E and HCoV-OC43 rates of infection were positively related to atmospheric pressure, while HCoV-229E was also positively associated with particulate matter concentrations. Our results suggest that climatic variables affect the rate in which children below 10 years of age are infected with HCoV. These findings may help to predict when prevention strategies may be most effective.

소아약증직결(小兒藥證直訣)에 기재(記載)된 방제(方劑)의 특성분석(特性分析) (A Study on Formulas in "Xi$\v{a}$o' Er Y$\`{a}$o Zh$\`{e}$ng Zh$\'{\i}$ Ju$\'{\e}$(小儿藥証直訣)")

  • 조현진;박선동
    • 대한한의학방제학회지
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    • 제19권1호
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    • pp.35-49
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    • 2011
  • Objectives : This study aims to reveal the characteristics of formulas in "Xi$\v{a}$o' Er Y$\`{a}$o Zh$\`{e}$ng Zh$\'{\i}$ Ju$\'{\e}$. Methods : For that objectives, We analyzes formulas in "Xi$\v{a}$o' Er Y$\`{a}$o Zh$\`{e}$ng Zh$\'{\i}$ Ju$\'{\e}$. In the text, 132 formulas were described. To comprehend the formulas, we classified them as several bases. Results : After those analyses, we bring to a conclusion as follows. 1. 30 formulas are described that treated convulsive diseases (j$\={i}$ngf$\={e}$ng, 惊風). Next, g$\={a}$n(疳), parasite infection, diarrhea/dysentery, dermatosis and etc were in the order. 2. Classified by the formulation, Yu$\'{\a}$nj$\`{i}$(圓劑) was the best(70 kinds of formulas, 53%). S$\v{a}$nj$\`{i}$(散劑) was a form of 41 formulas(31%). T$\={a}$ngj$\`{i}$(湯劑) and g$\={a}$oj$\`{i}$(膏劑) were a form of 5 formulas each. 10 formulas were assumed the form of w$\`{a}$iy$\`{o}$ngj$\`{i}$(外用劑). 3. We researched in-depth analysis of Yu$\'{\a}$nj$\`{i}$. As a results, dosage, additive(輔料) and the time to take of Yu$\'{\a}$nj$\`{i}$ were decomposed. Also, the formulas that treated convulsive diseases were analyzed by the herbs classification. Conclusions : Though the formulas that treated convulsive diseases were hard to application at local clinic, overall nosology of pediatrics was reflected comparatively. "Xi$\v{a}$o' Er Y$\`{a}$o Zh$\`{e}$ng Zh$\'{\i}$ Ju$\'{\e}$ was expected to play a role for reconsideration of formulas' formulation.

A NOTE ON WITT RINGS OF 2-FOLD FULL RINGS

  • Cho, In-Ho;Kim, Jae-Gyeom
    • 대한수학회보
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    • 제22권2호
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    • pp.121-126
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    • 1985
  • D.K. Harrison [5] has shown that if R and S are fields of characteristic different from 2, then two Witt rings W(R) and W(S) are isomorphic if and only if W(R)/I(R)$^{3}$ and W(S)/I(S)$^{3}$ are isomorphic where I(R) and I(S) denote the fundamental ideals of W(R) and W(S) respectively. In [1], J.K. Arason and A. Pfister proved a corresponding result when the characteristics of R and S are 2, and, in [9], K.I. Mandelberg proved the result when R and S are commutative semi-local rings having 2 a unit. In this paper, we prove the result when R and S are 2-fold full rings. Throughout this paper, unless otherwise specified, we assume that R is a commutative ring having 2 a unit. A quadratic space (V, B, .phi.) over R is a finitely generated projective R-module V with a symmetric bilinear mapping B: V*V.rarw.R which is nondegenerate (i.e., the natural mapping V.rarw.Ho $m_{R}$ (V, R) induced by B is an isomorphism), and with a quadratic mapping .phi.:V.rarw.R such that B(x,y)=(.phi.(x+y)-.phi.(x)-.phi.(y))/2 and .phi.(rx)= $r^{2}$.phi.(x) for all x, y in V and r in R. We denote the group of multiplicative units of R by U(R). If (V, B, .phi.) is a free rank n quadratic space over R with an orthogonal basis { $x_{1}$, .., $x_{n}$}, we will write < $a_{1}$,.., $a_{n}$> for (V, B, .phi.) where the $a_{i}$=.phi.( $x_{i}$) are in U(R), and denote the space by the table [ $a_{ij}$ ] where $a_{ij}$ =B( $x_{i}$, $x_{j}$). In the case n=2 and B( $x_{1}$, $x_{2}$)=1/2, we reserve the notation [ $a_{11}$, $a_{22}$] for the space.the space.e.e.e.

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Single Device를 사용한 조도센서용 eFuse OTP IP 설계 (Design of eFuse OTP IP for Illumination Sensors Using Single Devices)

  • 에치크 수아드;김홍주;김도훈;권순우;하판봉;김영희
    • 전기전자학회논문지
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    • 제26권3호
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    • pp.422-429
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    • 2022
  • 조도센서 칩은 아날로그 회로의 트리밍이나 디지털 레지스터의 초기 값을 셋팅하기 위해 소용량의 eFuse(electrical Fuse) OTP(One-Time Programmable) 메모리 IP(Intellectual Property)를 필요로 한다. 본 논문에서는 1.8V LV(Low-Voltage) 로직 소자를 사용하지 않고 3.3V MV(Medium Voltage) 소자만 사용하여 128비트 eFuse OTP IP를 설계하였다. 3.3V 단일 MOS 소자로 설계한 eFuse OTP IP는 1.8V LV 소자의 gate oxide 마스크, NMOS와 PMOS의 LDD implant 마스크에 해당되는 총 3개의 마스크에 해당되는 공정비용을 줄일 수 있다. 그리고 1.8V voltage regulator 회로가 필요하지 않으므로 조도센서 칩 사이즈를 줄일 수 있다. 또한 조도센서 칩의 패키지 핀 수를 줄이기 위해 프로그램 전압인 VPGM 전압을 웨이퍼 테스트 동안 VPGM 패드를 통해 인가하고 패키징 이후는 PMOS 파워 스위칭 회로를 통해 VDD 전압을 인가하므로 패키지 핀 수를 줄일 수 있다.

$TlGaS_2:Er^{3+}$ 단결정의 Photoluminescence 특성 연구 (Photoluminescence Properties of $TlGaS_2:Er^{3+}$ Single Crystal)

  • 송호준;윤상현;김화택
    • 한국진공학회지
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    • 제2권3호
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    • pp.299-303
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    • 1993
  • Erbium metal을 불순물로서 2mol% 첨가한 TlGaS2:Er3+ 단결정을 수평전기로에서 합성한 ingot를 사용하여 수직 Bridgman 방법으로 성장시켰다. 성장된 결정은 층상으로 이루어진 monoclinic 구조였으며, 10K에서 간접전이형 및 직접전이형 energy band gap은 각각 2.55eV, 2.57eV이었고, Er3+ 이온에 의한 두 개의 불순물 광흡수 peak가 524.9nm와 656.4nm에서 관측되었다. Themally stimulated current(TSC)를 측정하여 0.21eV와 0.38eV의 donor 준위와 0.71eV의 accptor 준위를 구하였다. 10K에서 측정된 photoluminescence(PL) spectrum에서는 632nm와 759nm에서 D-A pair에 의한 broad한 peak와 552, 559, 666, 813, 816, 827nm에서 Er3+ 이온에 의한 sharp한 peak들이 나타났다.

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$V_2O_5$ 첨가가 $TiO_2$ 세라믹스의 물성에 미치는 효과 (Effects on Properties of $V_2O_5$-added $TiO_2$ Ceramics)

  • 유도현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 학술대회 논문집 전문대학교육위원
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    • pp.138-140
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    • 2007
  • $TiO_2-V_2O_5$ sol was fabricated using sol-gel method and $TiO_2-V_2O_5$ thin films were fabricated using dip-coating method. $V_2O_5$ sol was added 0.01mo1e, 0.03mo1e, 0.05mo1e into $TiO_2$ sol. Viscosity of sol increased fast from about 1,000 minutes and sol began gelation from about 10,000 minutes. As a results of crystalline properties, $V_2O_5$ peaks were not found despite of $V_2O_5$ addition. Endothermic reaction occurred due to evaporation of solvent and dissociation of OH at $80^{\circ}C$. Exothermic reaction occurred due to combustion and oxidation of solvent at $230^{\circ}C$, occurred to combustion and oxidation of alkyl group at $350^{\circ}C$. Thickness of thin films increased $0.1{\sim}0.25{\mu}m$ every a dipping.

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JOINT NUMERICAL RANGES IN NON UNITAL NORMED ALGEBRAS

  • Yang, Young-Oh
    • 대한수학회논문집
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    • 제9권4호
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    • pp.837-846
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    • 1994
  • Let A denote a unital normed algebra over a field K = R or C and let e be the identity of A. Given $a \in A$ and $x \in A$ with $\Vert x \Vert = 1$, let $$ V(A, a, x) = {f(ax) : f \in A', f(x) = 1 = \Vert f \Vert}. $$ Then the (Bonsall and Duncan) numerical range of an element $a \in A$ is defined by $$ V(a) = \cup{V(A, a, x) : x \in A, \Vert x \Vert = 1}, $$ where A' denotes the dual of A. In [2], $V(a) = {f(a) : f \in A', f(e) = 1 = \Vert f \Vert}$.

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The critical Mg doping on the blue light emission in p-type GaN thin films grown by metal-organic chemical vapor deposition

  • Kim, Keun-Joo
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 기술교육위원회 창립총회 및 학술대회 의료기기전시회
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    • pp.52-59
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    • 2001
  • The photoluminescence and the photo-current from p-type GaN films were investigated on both room- and low-temperatures for various Mg doping concentrations. At a low Mg doping level, there exists a photoluminescence center of the donor and the acceptor pair transition of the 3.28-eV band. This center is correlated with the defects for a shallow donor of the VGa and for an acceptor of MgGa. The acceptor level shows the binding energy of 0.2-0.25 eV, which was observed by the photon energy of the photo-current signal of 3.02-3.31 eV. At a high Mg doping level, there is a photoluminescence center of a deep donor and an acceptor pair transition of the 2.76-eV blue band. This center is attributed to the defect structures of MgGa-VN for the deep donor and MgGa for the acceptor. For low. doped samples, thermal annealing provides an additional photo-current signal for an unoccupied deep acceptor levels of 0.87-1.35 eV above valence band, indicating the p-type activation.

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