• Title/Summary/Keyword: Light I-V

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Effect of Vibrio alginolyticus on the Algicidal Activity of Shewanella sp. SR-14 (Vibrio alginolyticus가 Shewanella sp. SR-14의 미세조류 증식저해 활성에 미치는 영향)

  • KIM Ji Hoe;PARK Hee Yeon;LEE Tae Seek;KIM Shin-Hee;PARK Jeong Heum;CHANG Dong Suck
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.5
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    • pp.430-434
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    • 2001
  • The algicidal activity of Shewanella (formerly Alteromonas) sp. SR-14 against diatom, Chaetoceros calcitrans was reported in our previous papers. In this study, the effect of Vibrio alginolyticus on the algicidal activity of Shewanelia sp, SR-14 was examined under the optimum algicidal conditions, i.e., temperature ($21\pm1^{\circ}C$), light intensity (4,000 lux), and light: dark cycle (12 hour: 12 hour). Shewanella sp. SR-14 grew well in the presence or the absence of V. alginolyticus in Conwy medium. Algal growth was only inhibited by Shewanella sp. SR-14. V. alginolyticus did not show the algicidal activity, Growth of C. calcitrans increased synergistically with growth of V. alginolyticus. When the initial inoculum of V. alginolyticus was only 1 log cycle higher than that of Shewanella sp. SR-14, the effect of V. alginolyticus on the algicidal activity of Shewanella sp. SR-14 was insignificant during incubation of mixed culture, i.e., two bacterial species and the alga. However, when V. alginolyticus dominated Shewanella sp. SR-14 by 3 log cycles of bacterial counts, it was found that the strain SR-14 could not inhibited growth of C. calcitrans up to 5 days of incubation.

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A study on the Healing Effects of UV-Day light for the healthy Leprosy Center through the ANOVA statistical analysis - Focused on 5S (Sort, Straighten, Shine, Standardize, Sustain)

  • Shaikh, Javaria Manzoor;Park, JaeSeung
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.19 no.4
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    • pp.7-18
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    • 2013
  • Purpose: The aim of this paper is to reduce the stress and the disturbance occur in selective action of patient. This article will also help us to control spreading and reduce the order and bacteria produced by leprosy disease among the lepers. This will be achieved with the help of several variables and these variables help us on health benefits is 5S (Sort, Straighten, Shine, Standardize, Sustain) i.e. ratio of sectional morphology, lessor 90 degree angles, day light, universal design building and maximum ventilation. The replies from the questionnaire were collected based on varying levels of satisfaction and gloominess on the scale of 1-10. Methods: The multi-layer methodological framework for maximising the healing environment obtained from the observation of schemes and parameters of ANOVA: (Analysis Of Variance between five deciding factors) are. Firstly applied for the calculation of the patient's satisfaction for U.V light from sun on ECOTECT simulation, secondly the number of $90^{\circ}$ angle, along the corridors. Thirdly understanding the ways to represent people's perceptual structures and way finding with Space Syntax software. Fourthly the ratio of depth to height of the building typology and finally interviewing the subjects describing their special experiences based on scale value. The focus of this testing of human subjects was to receive data for the existence of image scheme in way-finding and to identify the mechanisms by which sun light impacts human (lepers) health. Results: AMPVA studies concluded that there is similarity between I and O plan as well as L and H plan whereas U plan was difference among the five selected architectural shapes. Implications: The purpose of this research is to show the effects of the I-type, L-type, C-type, U-type and O-type plan design, and to analyse the morphology for EBD (Evidence-Based Design) healing environment which is a universal design for Munghopir Karachi, in Pakistan.

Determination of optical constants for organic light emitting material of Alq3 using Forouhi-Bloomer dispersion relations (포로히-블루머(Forouhi-Bloomer) 분산식을 이용한 유기발광물질 Alq3의 광학 상수 결정)

  • 정부영;우석훈;이석목;황보창권
    • Korean Journal of Optics and Photonics
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    • v.14 no.1
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    • pp.1-7
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    • 2003
  • We determined the optical constants of organic light emitting material of Alq$_3$ in a spectral range between 1.5 and 6 eV using the physical model introduced by Forouhi and Bloomer[Phys. Rev. B 34, pp. 7018-7026, 1986.]. The initial parameters of $A_i,\;B_i,\;C_i$ of Forouhi-Bloomer dispersion relations were determined from the absorption peaks and widths of absorption spectra of the Alq$_3$ film. The refractive index of substrate, a fused silica, is derived from the Sellmeier equation with the measured transmittance and reflectance spectra. Then, the complex refractive index and thickness of the Alq$_3$ film were calculated by use of a nonlinear least square fitting program with the Forouhi-Bloomer dispersion relation and the measured transmittance and reflectance spectra.

A Study on the Electrical Characteristic Analysis of c-Si Solar Cell Diodes

  • Choi, Pyung-Ho;Kim, Hyo-Jung;Baek, Do-Hyun;Choi, Byoung-Deog
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.12 no.1
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    • pp.59-65
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    • 2012
  • A study on the electrical characteristic analysis of solar cell diodes under experimental conditions of varying temperature and frequency has been conducted. From the current-voltage (I-V) measurements, at the room temperature, we obtained the ideality factor (n) for Space Charge Region (SCR) and Quasi-Neutral Region (QNR) of 3.02 and 1.76, respectively. Characteristics showed that the value of n (at SCR) decreases with rising temperature and n (at QNR) increases with the same conditions. These are due to not only the sharply increased SCR current flow but the activated carrier recombination in the bulk region caused by defects such as contamination, dangling bonds. In addition, from the I-V measurements implemented to confirm the junction uniformity of cells, the average current dispersion was 40.87% and 10.59% at the region of SCR and QNR, respectively. These phenomena were caused by the pyramidal textured junction structure formed to improve the light absorption on the device's front surface, and these affect to the total diode current flow. These defect and textured junction structure will be causes that solar cell diodes have non-ideal electrical characteristics compared with general p-n junction diodes. Also, through the capacitance-voltage (C-V) measurements under the frequency of 180 kHz, we confirmed that the value of built-in potential is 0.63 V.

Study of electric properties of pentacene field effect transistor using C- V and SHG measurements (C-V, SHG를 이용한 pentacene FFT의 전기적 특성 연구)

  • Lim, Eun-Ju;Takaaki, Manaka;Tamura, Ryosuke;Iwamoto, Mitsumasa
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.06a
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    • pp.70-71
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    • 2007
  • Analyzing pentacene field effect transistors (FETs) with Au source and drain electrodes as Maxwell-Wagner effect elements, electron and hole injection from the Au electrodes into the FET channel were examined using current-voltage (I-V), capacitance-voltage (C-V) and optical second harmonic generation (SHG) measurements. Based on these results, a mechanism of the hole and electron injection into pentacene from the Au electrodes and subsequently recombination mechanism with light-emitting in the pentacene layer are discussed, with taking into account the presence of trapped charges.

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Measurement of Branching Ratio for broad 27-keV Resonance of $^{19}F(n,g)^{20}F$ Reaction by using Time-of-flight Method with Anti-Compton NaI(Tl) Spectrometer

  • Lee, Sam-Yol
    • Journal of the Korean Society of Radiology
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    • v.2 no.1
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    • pp.31-34
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    • 2008
  • The neutron capture spectrum for the light nuclide was very useful to study the nuclear structure. In the present study, the capture gamma-ray from the 27-keV resonance of $^{19}F(n,g)^{20}F$ reaction were measured with an anti-Compton NaI(Tl) spectrometer and the 3-MV Pelletron accelerator of the Research Laboratory for Nuclear Reactors at the Tokyo institute of technology. A neutron Time-of-Flight method was adopted with a 1.5 ns pulsed neutron source by the $^7Li(p,n)^7Be$ reaction. In the present experiment, a Teflon(($CF_2$)n) sample was used The sample was disk with a diameter of 90mm. The thickness of sample was determined so that reasonable counting rates could be obtained and the correction was not so large for the self-shielding and multiple scattering of neutrons in the sample, and was 5mm. The primary gamma-ray transitions were compared with previous measurement of Kenny.

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Electrical characteristics of MEH-PPV thin films for light-emitting diodes (MEH-PPV를 이용한 유기전기발광소자의 전기적 특성)

  • 이상윤;이한성;김정수;이광연;김영관;신동명;손병청
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1998.06a
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    • pp.253-257
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    • 1998
  • Organic-based electroluminescent devices have attracted lots of interests because of their possible application as large-area flat pan디 display. In this study, current-voltage (I-V) characteristics of MEH-PPV thin films was investigated using various metal as a top electrode, where MEH-PPV thin films were prepared on 170 substrate by spin coating method and various metal such as Al, Ag, In, MgIn was deposited on MEH-PPV thin films as a top electrode.

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Utilization of Photoconductive Gain Mechanism in Amorphous Silicon Radiation Detectors (비정질 실리콘 방사선 계측기에서의 Photoconductive Gain의 응용)

  • Lee, H.K.;Suh, T.S.;Choe, B.Y.;Shinn, K.S.;Cho, G.;Perez-Mendez, V.
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.05
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    • pp.457-460
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    • 1997
  • The photoconductive gain mechanism in various types of hydrogenated amorphous silicon devices, such as p-i-n, n-i-n and n-i-p-i-n structures was investigated in connection with applications to radiation detection. We measured the photoconductive gain in two time scales: one for short pulses of visible light $(<1{\mu}sec)$ which simulate the transit of energetic charged particles, and the other for rather long pulses of light $(\sim1msec)$ which simulate x-ray exposure in medical imaging. We used two definitions of photoconductive gain: current gain and charge gain which is an integration of the current gain. We found typical charge gains of $3\sim9$ for short pulses and a few hundred for long pulses at a dark current density level of $10mA/cm^2$.

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Influence of UV Irradiation Procedures on the Concentration of Vitamin $D_{3}$ and 25-Hydroxyvitamin $D_{3}$ in the Liver and Skeleton of Broiler Chicks (자외선 조사방법이 육계 병아리의 간장과 골격중 Vitamin $D_{3}$ 및 25-Hydroxyvitamin $D_{3}$ 농도에 미치는 영향)

  • ;;M.F.Holick
    • Korean Journal of Poultry Science
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    • v.21 no.3
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    • pp.157-168
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    • 1994
  • This study was carried out to elucidate the time course variation of vitamin $D_{3}$ (V$D_{3}$) and 25-hydroxyvitamin $D_{3}$ [25(OH)$D_{3}$] contents in the liver and skeleton of 3-wk old broiler chicks when treated with different UV irradiation procedure. Day-old Hubbard chicks were fed vitamin D deficient diet for 3 wk and exposed to medium wave ultraviolet(UVB) light with different irradiation procedures. Procedure I was 30 min continuous irradiation(O.204 mJ /$cm^{2}$) and Procedure II was three seperate 10 min irradiation with 12 h intervals, and Procedure III was three seperate 10 min irradiation with 24 h intervals. The liver and skeleton samples were collected at 10 different times between 0000~2400 h after the last irradiation. The V$D_{3}$ and 25(OH)$D_{3}$ fractions wereseparated by Sep-Pak silica cartridge and the concentrations were determined by normal phase HPLC. The mean content of V$D_{3}$ in the liver of the birds treated by Procedure II was 6.68 ng /g, which was higher than 5.60 and 5.30 ng /g from Procedure I and Ill, respectively(P<.O5). With regard to the effect of elapsed time after UVB irradiation on the V$D_{3}$ concentration of the liver, 96 h treatment showed the highest value(13.08 ng/g)(P<.05). There was a significant(P$D_{3}$ were significantly(P$D_{3}$ in the skeleton of tibia and femur, there were no significant differences among Procedure I, II and III, but significant differences were found among those from various elapsed time after irradiation, The highest value was shown at 96 h(O.99 ng /g) treatment, and interaction between irradiation procedure and elapsed time was not significant. With regard to the mean content of 25(OH)$D_{3}$ in bone, the Procedure II(18.79 ng /g) and III(17.73 ng /g) showed higher values than Procedure I did (P<.05), and the 12 h elapsed time showed the highest value(31.17 ng /g) among 10 treatments (P<.05), however, there was no significant interaction between exposing procedure and elapsed time. In conclusion, the Procedure II would he more desirable than Procedure I or III to produce more V$D_{3}$ and 25(OH)$D_{3}$ in the liver and skeleton of birds by exposing to the UVB light. Also, it was verified that 25(OH)$D_{3}$ increases more quickly than V$D_{3}$ in both tissues tested and is utilized more quickly to recover from the rickets of chicks.

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A study on the degradation of the AC stressed MOV by using of the DLTS technique (DLTS기법에 의한 MOV소자의 교류과전경시 변화특성에 관한 연구)

  • 이동희
    • Electrical & Electronic Materials
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    • v.9 no.7
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    • pp.719-726
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    • 1996
  • DLTS measurements were performed to study the annealing induced changes of the trap centers in MOV and to shed more light on the stability mechanism of the MOV. Two electron traps, Ec-0.26[eV] and Ec-(O.2-0.3)[eV], were observed in the unannealed samples in large quantities(7-9 X 1014[CM 3]), whereas the three electron traps Ec-0.17 [eV], Ec-0.26[eV] and Ec-(O.2-0.3)[eV] were observed far less in the annealed samples. The minima in the Ec-0.26[eV] trap density, coupled with the presented results that unannealed devices are unstable whereas 600.deg. C annealed devices are most stable, suggests that the instability of the MOV under long term electrical stressing is related to the Ec-0.26[eV] trap. This results support that the ion migration model for the device instability where the Ec-0.26[eV] defects may be the interstitial zinc or the migrating ions. The interstitial zinc originated as a result of the nonstoichiometric nature of ZnO might cause the degradation of the I-V characteristics of the MOV with long term electrical stressing.

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