• Title/Summary/Keyword: H-gate

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What Can Caenorhabditis elegans Tell Us About Nematiocides and Parasites\ulcorner

  • Dent, Joseph A.
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.6 no.4
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    • pp.252-263
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    • 2001
  • Nematode infections compromise human health and reduce agricultural productivtiy. Experiments that exploit the powerful molecular genetics of the free-living nematode Caenorhabdl - elegans have contributed to our understanding of how the major classes of anthelmintic nema-tocides kill worms and how worms might evolve resistance to these drugs In C. elegans, as in parasites, benzimidixoles interfere with microtubule polyumerization the imidazothiazoles/tetra-hydropyrimidines activate nicotinic acetylcholine receptors, and the macrocyclic la ctones activate qlutamate-gate chloride chanels. Mutant alleles of genes that encode drug targes often confer resistance in C. elegans. Preliminary evidence suggests that alleles of homologous genes in parasites will, in many cases, also play a role in resistance. Thus information acquired from C. elegans can be usefully applied to understand the mechanisms of drug sensitivity and the genetics of resis-tance in parasites.

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Vector Controlled Inverter for Elevator Drive (ELEVATOR 구동용 VECTOR 제어 인버터)

  • Shin, H.J.;Jang, S.Y.;Lee, S.J.;Lee, S.D.
    • Proceedings of the KIEE Conference
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    • 1991.07a
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    • pp.627-630
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    • 1991
  • This study is about vector controlled inverter for high quality elevator drive that is to improve the settling accuracy of elevator car and passenger's comfort in commercial buildings. In this study, an instantaneous space vector control type inverter was used to reduce the torque ripple ant to improve the velocity follow-up. This method calculates Instantaneous actual output torque and flux of induction motor by voltage and current, then compares them with a reference values by a speed regulator. The outputs of comparators select a switching mode, for an optimal voltage vector. Also, this study used IGBT (Insulated Gate Bipolar-Transistor), a high speed switching element, to reduce sound noise level, and DSP (Digital Signal Processor) was used to improve the reliability of the control circuit by fully digitalization.

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Preparation and Characterization of Plasma Polymerized Methyl Methacrylate Thin Films as Gate Dielectric for Organic Thin Film Transistor

  • Ao, Wei;Lim, Jae-Sung;Shin, Paik-Kyun
    • Journal of Electrical Engineering and Technology
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    • v.6 no.6
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    • pp.836-841
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    • 2011
  • Plasma polymerized methyl methacrylate (ppMMA) thin films were deposited by plasma polymerization technique with different plasma powers and subsequently thermally treated at temperatures of 60 to $150^{\circ}C$. To find a better ppMMA preparation technique for application to organic thin film transistor (OTFT) as dielectric layer, the chemical composition, surface morphology, and electrical properties of ppMMA were investigated. The effect of ppMMA thin-film preparation conditions on the resulting thin film properties were discussed, specifically O-H site content in the pMMA, dielectric constant, leakage current density, and hysteresis.

Pulsed Power Modulator based on IGBTs (IGBT 기반 고압 펄스전원장치)

  • Ryoo, H.J.
    • Proceedings of the KIPE Conference
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    • 2007.11a
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    • pp.43-46
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    • 2007
  • In this paper, a novel new pulse power generator based on IGBT stacks is proposed for pulse power application. Proposed scheme consists of series connected 9 power stages to generate maximum 60kV output pulse and one series resonant power inverter to charge DC capacitor voltage. Each power stages are configured as 8 series connected power cells and each power cell generates up to 850VDC pulse. Finally pulse output voltage is applied using total 72 series connected IGBTs. The synchronization of gating signal is important for series operation of IGBTs. For gating signal synchronization, full bridge inverter and pulse transformer generates on-off signals of IGBT gating and specially designed gate power circuit was used. Proposed scheme has lots of advantages such as long lifecyle, compact size, flat topped pulse forming, small weight, protection for arc, high efficiency and flexibility to generate various kinds of pulse output.

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FPGA Based PWM Generator for Three-phase Multilevel Inverter

  • Tran, Q.V.;Chun, T.W.;Kim, H.G.;Nho, E.C.
    • Proceedings of the KIPE Conference
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    • 2008.06a
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    • pp.225-227
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    • 2008
  • This paper deals with the implementation on a Field Programmable Gate Array (FPGA) of PWM switching patterns for a voltage multilevel inverter. The reference data in main microcontroller is transmitted to the FPGA through 16 general purpose I/O ports. Herein, three-phase reference voltage signals are addressed by the last 2-bit (bit 15-14) and their data are assigned in remaining 14-bit, respectively. The carrier signals are created by 16-bit counter in up-down counting mode inside FPGA according to desirable topology. Each reference signal is compared with all carrier signals to generate corresponding PWM switching patterns for control of the multilevel inverter. Useful advantages of this scheme are easy implementation, simple software control and flexibility in adaptation to produce many PWM signals. Some simulations and experiments are carried out to validate the proposed method.

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Functional Simulation of Logic Circuits by Prolog (Prolog를 이용한 논리회로의 기능적 시뮬레이션)

  • Kim, J.S.;Cho, S.B.;Park, H.J.;Lim, I.C.
    • Proceedings of the KIEE Conference
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    • 1987.07b
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    • pp.1467-1470
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    • 1987
  • This paper proposes a functional simulation algorithm which decrease the internal memory space and run time in simulation of VLSI. Flip-flop, register, ram, rom, ic and fun are described as functional elements in the simulator. Especially icf is made as new functional element by combining the gate and the functional element, therefore icf is used efficiently in simulation of VLSI. The proposed algorithm is implemented on PC-AT(MS-DOS) in by Prolog-1.

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Characterization of Silicon Structures with pn-junctions Fabricated by Modified Direct Bonding Technique with Simultaneous Dopant Diffusion (불순물 확산을 동시에 수행하는 수정된 직접접합방법으로 제작된 pn 접합 실리콘소자의 특성)

  • Kim, Sang-Cheol;Kim, Eun-dong;Kim, Nam-kyun;Bahng, Wook;Kostina, L.S.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.828-831
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    • 2001
  • A simple and versatile method of manufacturing semiconductor devices with pn-junctions used the silicon direct bonding technology with simultaneous impurity diffusion is suggested . Formation of p- or n- type layers was tried during the bonding procedure by attaching two wafers in the aqueous solutions of Al(NO$_3$)$_3$, Ga(NO$_3$)$_3$, HBO$_3$, or H$_3$PO$_4$. An essential improvement of bonding interface structural quality was detected and a model for the explanation is suggested. Diode, Dynistor, and BGGTO structures were fabricated and examined. Their switching characteristics are presented.

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Development of TFT-LCD panel with reduced driver ICs

  • Kim, Sung-Man;Lee, Jong-Hyuk;Lee, Hong-Woo;Lee, Jong-Hwan;Choi, Kwang-Soo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.352-354
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    • 2008
  • A 15.4" WXGA TFT-LCD, featuring integrated a-Si:H gate driver circuits and reduced data driver ICs, has been developed. To reduce number of data lines into 1/2 of conventional structure, the pixel array has been re-mapped with re-organized data signal. Unintended artificial effects such as flicker were removed by adopting the novel pixel array having a 'zigzag' map. To minimize the power consumption, a column inversion method was incorporated in the zigzag pixel array (Fig.1) without modifying the polarity map of conventional dot inversion method.

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A Method to Predict the Performance of a-Si TFT device

  • Shih, Ching-Chieh;Wei, Chun-Ching;Wu, Yang-En;Gan, Feng-Yuan
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.52-55
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    • 2006
  • The driving-current degradation of a-Si:H thin-film transistor(TFT) device has been analyzed for the first time. A method to analyze the performance of TFT circuits is presented, which is different from the conventional one by threshold voltage shift method. It can be also used to evaluate the performance of gate driver on array (GOA) circuit, which is integrated in a 12.1" WXGA ($1280{\ast}3{\ast}800$) TFT-LCD panel.

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Photo-Leakage Currents in Organic Thin-Film Transistor

  • Cho, Sang-Mi;Han, Seung-Hoon;Kim, Jun-Hee;Lee, Sun-Hee;Choo, Dong-June;Uchiike, H.;Oh, Myung-Hwan;Jang, Jin
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1386-1389
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    • 2005
  • We report the light illumination effect on the performance of pentacene organic thin-film transistor (OTFT). The TFT performance with and without illumination were measured at various temperatures. The off-state currents increase linearly with light intensity in the region of gate voltage where the holes are majority carriers in the TFT channel. The minimum photocurrents of OTFT increase with increasing light intensity.

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