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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
281

A programmable delta-sigma modulator using floating gates

Allen, Daniel J., January 2003 (has links) (PDF)
Thesis (M.S. in E.E.)--School of Electrical and Computer Engineering, Georgia Institute of Technology, 2004. Directed by David V. Anderson. / Includes bibliographical references (leaves 55-56).
282

Stacked inverted top-emitting white organic light-emitting diodes

Najafabadi, Ehsan 12 January 2015 (has links)
The majority of research on Organic Light-Emitting Diodes (OLEDs) has focused on a top-cathode, conventional bottom-emitting architecture. Yet bottom-cathode, inverted top-emitting OLEDs offer some advantages from an applications point of view. In this thesis, the development of high performance green electroluminescent inverted top-emitting diodes is first presented. The challenges in producing an inverted structure are discussed and the advantages of high efficiency inverted top-emitting OLEDs are provided. Next, the transition to a stacked architecture with separate orange and blue emitting layers is demonstrated, allowing for white emission. The pros and cons of the existing device structure is described, with an eye to future developments and proposed follow-up research.
283

Numerical electromagnetics codes problems, solutions and applications.

Zeineddin, Rafik Paul. January 1993 (has links)
Thesis (M.S.)--Ohio University, March, 1993. / Title from PDF t.p.
284

Reduced Third Order Intermodulation Distortion Utilizing a Push-Pull Class C VHF Transistorized Amplifier

Mosher, Norman B. 01 January 1974 (has links) (PDF)
In a transistorized push-pull amplifier, third order intermodulation distortion was effectively reduced at VHF frequencies with an output power of two watt. The non-linear distortion of the amplifier is modeled using a power series. The resulting expression is used as the basis for choosing the push-pull configuration to reduce the third order intermodulation distortion. The amplifier was built and tested, and the experimental results compare favorably with the theoretical results. The level of the third order intermodulation distortion is found to be at least 30 dB below the interfering signal level.
285

Study of soft-switching techniques on three-level three-phase four-wire active power filters

Lok, Io Keong January 2010 (has links)
University of Macau / Faculty of Science and Technology / Department of Electrical and Electronics Engineering
286

Empirical parameterization of organic electrochemical transistors

Larsson, Oscar January 2004 (has links)
In this diploma work, organic electrochemical transistors based on PEDOT:PSS have been studied, focusing on the influence of the geometry and physical dimensions on the transistor characteristics. The geometrical parameters studied are the area ratio between the gate and channel, the channel width and the channel length. Each parameter has been varied in five steps with each step containing three identical transistors. Results concerning the geometrical influence of the linear region resistance, the saturation current (density) and the on/off ratio are presented and discussed. Also, empirical curve-fits of the geometrical influence on the linear region resistance and the saturation current have been performed. In addition, tentative results of the locus of the saturation current versus saturation voltage for specific transistors have been obtained.
287

Empirical parameterization of organic electrochemical transistors

Larsson, Oscar January 2004 (has links)
<p>In this diploma work, organic electrochemical transistors based on PEDOT:PSS have been studied, focusing on the influence of the geometry and physical dimensions on the transistor characteristics. The geometrical parameters studied are the area ratio between the gate and channel, the channel width and the channel length. Each parameter has been varied in five steps with each step containing three identical transistors. Results concerning the geometrical influence of the linear region resistance, the saturation current (density) and the on/off ratio are presented and discussed. Also, empirical curve-fits of the geometrical influence on the linear region resistance and the saturation current have been performed. In addition, tentative results of the locus of the saturation current versus saturation voltage for specific transistors have been obtained.</p>
288

Design and use of surface modifiers as tools for understanding and controlling interfaces in organic electronics

Smith, O'neil Lohanica 22 May 2014 (has links)
This thesis focuses on the use of surface modifiers as tools for probing and/or controlling interfaces. Surface modification of transparent conducting oxides (TCOs) with organic and organometallic modifiers can be used as a tool for mediating interfacial energetics as well as probing the kinetics of charge-transfer at the metal oxide/organic interface. The synthetic tunability of these modifiers allows us to design molecules based on various parameters, which include the nature of the binding, spacer, and terminal groups. Based on this framework, several modifiers were synthesized and used to investigate surface energy tuning as well as charge injection kinetics as a function of molecular structure. More specifically, we use XPS/UPS to examine the evolution of the chemical structure and frontier orbital levels of the TCO/organic interface as a function of the chosen surface modifier. In addition, we investigate the impact that various molecular binding groups have on mediating the kinetics of charge-transfer. In the last section of this body of work we examine the development of dielectric nanocomposite films for capacitor applications. More specifically, we examine the use of phosphonic acid modifiers to functionalize barium titanate nanoparticles in order to provide miscibility with a suitable polymer host. The effect of various modifiers on the dielectric properties not nanocomposite thin films was examined.
289

Active microwave arrays for medical hyperthermia: Device selection, characterization and implementation of their drive circuits

Hill, Michael James, 1971- January 1996 (has links)
Significant progress toward a functional 73 element, 730 watt, active microwave phased array has been made. This array, designed for medical hyperthermia applications, has significant size restrictions leading to a novel space conscious design. Unlike other hyperthermia devices, each array element is designed to have full 360° phase control with better than 1° resolution. Full amplitude control, with 10 bit amplitude resolution is implemented. The array is designed to operate in the 2.45 GHz ISM band. Measured operational data is presented and is compared to simulations performed with Compact Software's Microwave Harmonica®. A sophisticated control system for the array has been designed, built and tested. The system provides 160 computer controlled 10 bit analog control lines to drive the array. Sampling of various system parameters is made possible through the use of a 96 channel, 12 bit analog to digital converter system. This system provides 4 mV resolution and a 440 Hz sampling rate for each of the 96 measurement channels.
290

Implementering av en adaptiv kanalutjämnare för undervattenskommunikation / Implementation of an adaptive equaliser for underwater communication

Carlström, Johan January 2003 (has links)
<p>Denna rapport behandlar akustisk undervattenskommunikation. I rapporten tas olika aspekter upp på modulering, demodulering, kanalutjämning, den akustiska undervattenskanalens egenskaper samt andra fenomen och problem som kan uppkomma vid undervattenskommunikation. Speciellt har vikten i rapporten lagts vid adaptiva kanalutjämnare. </p><p>Utifrån olika simuleringar provades en undervattenskommunikationsmodell under fältmässiga förhållanden. Resultatet av utprovningen visade att differentiellt fasskift i kombination med en kanalutjämnare fungerade väl under rådande förhållanden. </p><p>I rapportens senare del beskrivs ett undervattenskommunikationssystem uppbyggd kring en Xilinx Spartan2 FPGA. Konstruktionen är resultatet av de teoretiska och praktiska slutsatser som framkommit under arbetets gång.</p>

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