• Title/Summary/Keyword: V² control

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A CMOS Temperature Control Circuit for Direct Mounting of Quartz Crystal on a PLL Chip (온 칩 수정발진기를 위한 CMOS 온도 제어회로)

  • Park, Cheol-Young
    • Journal of Korea Society of Industrial Information Systems
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    • v.12 no.2
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    • pp.79-84
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    • 2007
  • This papar reports design and fabrication of CMOS temperature control circuit using MOSIS 0.25um-3.3V CMOS technology. The proposed circuit has a temperature coefficient of $13mV/^{\circ}C$ for a wide operating temperature range with a good linearity. Furthermore, the temperature coefficient of output voltage can be controlled by adjusting external bias voltage. This circuit my be applicable to the design of one-chip IC where quartz crystal resonator is mounted on CMOS oscillator chips.

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The Effects of Waste Leachate on the Eco-Physiological Characteristics of Populus euramericana

  • Woo, Su-Young
    • The Korean Journal of Ecology
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    • v.22 no.6
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    • pp.343-348
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    • 1999
  • Populus euramericana has been identified as a possible species for use for phytoremediation of landfills. To identify the effects of waste leachate on the growth and physiological characteristics of Populus euramericana. four different treatments were applied to Populus euramericana seedlings: leachate solution (100% leachate). 25% dilution (75% leachate: 25% water. v/v), 50% dilution (50% leachate: 50% water. v/v) and control (100% tab water) were applied to Populus euramericana. Treatment with waste leachate significantly stimulated Populus euramericana height. diameter at root collar and biomass production relative to the water control. Chlorophyll contents. photosynthesis and transpiration of leachate irrigated-trees were significantly higher than those of water control. These results suggested that poplar could be a suitable species for phytoremediation in landfills because these species showed good growth performance and were capable of taking up waste leachate.

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A dP/dV Feedback-Controlled MPPT Method for Photovoltaic Power System Using II-SEPIC

  • Park, Han-Eol;Song, Joong-Ho
    • Journal of Power Electronics
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    • v.9 no.4
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    • pp.604-611
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    • 2009
  • A dP/dV feedback-controlled MPPT (Maximum Power Point Tracking) method for photovoltaic power systems using II-SEPIC (Isolated Inverse-SEPIC; Single Ended Primary Inductance Converter) is presented and a current-mode dP/dV feedback-controlled MPPT method is devised to apply for the PV power converter system. A control strategy for the current-mode dP/dV feedback control system is developed in this paper and the proposed MPPT shows relatively satisfactory dynamics against rapidly changing insolation conditions. In order to verify the validity and effectiveness of the proposed method, simulations and experiments of the PV power system using II-SEPlC converter are performed. These simulation and experiment results show that the proposed method enables the PV power system to extract maximum power from the photovoltaic module against the solar insolation variation.

V/f Tracking Control for Energy Saving (Energy Saving을 위한 V/f 추종제어)

  • Shin, Woo-Seok;Choe, Jae-Young;Lee, Don-Si;Choe, Gyu-Ha
    • Proceedings of the KIEE Conference
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    • 1993.07b
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    • pp.728-730
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    • 1993
  • This paper describes a simple but effective V/F control method for energy saving of a special-purpose Induction motor driven by PWM inverter. The proposed method is based on efficiency control with no speed sensor that the V/F patterns could be changed to load variations. The experimental results shows great improvement of both efficiency and power factor and usefulness of the method.

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Threshold Voltage control of Pentacene Thin-Film Transistor with Dual-Gate Structure

  • Koo, Jae-Bon;Ku, Chan-Hoe;Lim, Sang-Chul;Lee, Jung-Hun;Kim, Seong-Hyun;Lim, Jung-Wook;Yun, Sun-Jin;Yang, Yong-Suk;Suh, Kyung-Soo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.1103-1106
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    • 2006
  • We have presented a comprehensive study on threshold voltage $(V_{th})$ control of organic thin-film transistors (OTFTs) with dual-gate structure. The fabrication of dual-gate pentacene OTFTs using plasma-enhanced atomic layer deposited (PEALD) 150 nm thick $Al_2O_3$ as a bottom gate dielectric and 300 nm thick parylene or PEALD 200 nm thick $Al_2O_3$ as both a top gate dielectric and a passivation layer is reported. The $V_{th}$ of OTFT with 300 nm thick parylene as a top gate dielectric is changed from 4.7 V to 1.3 V and that with PEALD 200 nm thick $Al_2O_3$ as a top gate dielectric is changed from 1.95 V to -9.8 V when the voltage bias of top gate electrode is changed from -10 V to 10 V. The change of $V_{th}$ of OTFT with dual-gate structure has been successfully understood by an analysis of electrostatic potential.

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Threshold Voltage Control of Pentacene Thin-Film Transistor with Dual-Gate Structure

  • Koo, Jae-Bon;Ku, Chan-Hoe;Lim, Sang-Chul;Lee, Jung-Hun;Kim, Seong-Hyun;Lim, Jung-Wook;Yun, Sun-Jin;Yang, Yong-Suk;Suh, Kyung-Soo
    • Journal of Information Display
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    • v.7 no.3
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    • pp.27-30
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    • 2006
  • This paper presents a comprehensive study on threshold voltage $(V_{th})$ control of organic thin-film transistors (OTFTs) with dual-gate structure. The fabrication of dual-gate pentacene OTFTs using plasma-enhanced atomic layer deposited (PEALD) 150 nm thick $Al_{2}O_{3}$ as a bottom gate dielectric and 300 nm thick parylene or PEALD 200 nm thick $Al_{2}O_{3}$ as both a top gate dielectric and a passivation layer was investigated. The $V_{th}$ of OTFT with 300 nm thick parylene as a top gate dielectric was changed from 4.7 V to 1.3 V and that with PEALD 200 nm thick $Al_{2}O_{3}$ as a top gate dielectric was changed from 1.95 V to -9.8 V when the voltage bias of top gate electrode was changed from -10 V to 10 V. The change of $V_{th}$ of OTFT with dual-gate structure was successfully investigated by an analysis of electrostatic potential.

Prototype design of fiber optics based 765kV substation control system (광 LAN을 적용한 765kV변전소 감시제어 시범시스템 설계)

  • 송인호;박종화;최종협
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.996-999
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    • 1996
  • This paper introduces prototype design of 765kV Substation control system based on fiber optics LAN and distributed network protocol. Two major important facts, immunity of any surge which frequently occurs in Ultra High Voltage Substation and the most suitable communication protocol for substation control system, are considered on the system design conception. To meet the first fact, use of fiber optics cable and isolation transformer are considered, and to satisfy the second fact, DNP3.0(Distributed Network Protocol) which is IEC870-5 compatible is adopted.

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Effect of Substrates on Growth and Yield of Hydroponically Grown Cucumber in Bag Culture (자루재배에서 배지의 종류가 오이의 생육 및 수량에 미치는 영향)

  • 이응호;이재욱;권지선;남윤일;조일환;권영삼
    • Journal of Bio-Environment Control
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    • v.5 no.1
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    • pp.15-22
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    • 1996
  • Cucumbers(Cucumis sativus L. CV. SHARP 1) were cultivated by bag culture for 5 months to investigate the effect of substrates on growth, yield, and mineral contents. The substrates used in the experiment were vermiculite + perlite +peatmoss(1:1:1=V:V:V), perlite+peatmoss(1:1=V:V), perlite+carbonized chaff(7:3=V:V), rockwool, sawdust, and chaff+chaff powder under 10 mesh (7:3=V:V). The rate of moisture content was highest at chaff powder under 10 mesh as 42.5% and was lowest at perlite+carbonized chaff as 31%. Plant height, No. of leaves, fresh and dry weight were increased in vermiculite+perlite+peatmoss(1:1:1=V:V:V). Marketable fruits and yield also showed same aspect with growth. All kinds of mineral contents except K in cucumber plants were higher at vermiculite+perlite+peatmoss(1:1:1=V:V:V), but K content was higher at perlite+ carbonized chaff(7:3=V:V) than those other substrates.

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Effects of Coptidis Rhizoma on the Change of Interleukin-6 and $TNF-{\alpha}$ Level induced by LPS I.C.V. Injection in Mice (황연(黃連)이 Lipopolysaccharide 뇌실 주입으로 유발된 생쥐의 IL-6와 $TNF-{\alpha}$ 변화에 미치는 영향)

  • Sim Eun-Yeong;Yun Jeong-Moon;Lee Tae-Hee
    • Herbal Formula Science
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    • v.12 no.1
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    • pp.209-223
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    • 2004
  • Objective: This study was conducted to investigate the effects of Coptidis Rhizoma on the plasma IL-6 and $TNF-{\alpha}$ level in mice by intracerebroventricular(I.C.V.) injection of Lipopolysaccharide (LPS). Method: 6 mice were assigned to each of the Normal group, the Control group, and the individual Experimental groups. In the Normal group only saline was administered intragastrically, and in the Control group LPS was injected intracerebroventricularly 1 hr after intragastric administration of saline. In the Experimental groups Coptidis Rhizoma(0.5g/kg, 1.0g/kg, 3.0g/kg) was administered intragastrically to mice 1 hr prior to LPS (100ng/mouse) I.C.V. Injection. To measure the plasma IL-6 and $TNF-{\alpha}$ level of mice, their blood samples were collected from retro-orbital venous plexus, immediately centrifuged at $4^{\circ}C$, and plasma was removed and stored frozen at $-83^{\circ}C$ for later determination of plasma IL-6 and $TNF-{\alpha}$. Result: 1. LPS I.C.V. Injection increased plasma IL-6 level significantly in a dose-dependent manner compared with Normal group. (P<0.01) The plasma IL-6 concentration reached a significant maximal level about 1 hr after LPS(100ng/mouse) I.C.V. Injection.(P<0.001) 2. Both the 0.5g/kg(Sample A) and 1.0g/kg(Sample B) groups to which Coptidis Rhizoma was administered intragastrically 1 hr prior to LPS(100ng/mouse) I.C.V. Injection showed insignificant lower plama IL-6 level in 1 hr than Control group(P>0.05), and 3.0g/kg group(Sample C) conversely showed higher plama IL-6 level than Control group. 3. LPS I.C.V. Injection increased plasma $TNF-{\alpha}$ level significantly in a dose-dependent manner compared with Normal group.(P<0.05) The plasma $TNF-{\alpha}$ concentration reached a significant maximal level about 1 hr after LPS(100ng/mouse) I.C.V. Injection.(P<0.001) 4. All Sample groups(0.5g/kg, 1.0g/kg, and 3.0g/kg) to which Coptidis Rhizoma was administered intragastrically with each constituent-dose 1 hr prior to LPS(100ng/mouse) I.C.V. Injection showed significant lower $TNF-{\alpha}$ plama level in 1 hr than Control group.(P<0.001) These data revealed that Coptidis Rhizoma might have anti inflammatory effect by reducing the plasma $TNF-{\alpha}$ level in a dose dependent manner in mice LPS I.C.V. Injection.

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