• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • No language data
  • Tagged with
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 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.
1

A modular compact kW-class IPOS DC-DC converter for pulsed power applications

Thames, Walker Joseph 10 May 2024 (has links) (PDF)
Pulsed power systems are concerned with the delivery of significant amounts of power in a greatly condensed time frame. To achieve this, energy is often stored in a capacitor, where it can be rapidly discharged. Certain applications require repeated charging and discharging of the load capacitor in a specifically modulated manner; special power electronics systems must be developed for these situations. Existing systems on the market sacrifice a small form factor for greater pulsed power output. The proposed design outlines the development of a compact pulsed power capacitor charger capable of charging a load capacitor to high voltages at a pulse repetition frequency of 30 kHz. Due to the compact form factor, the charger features a unique design of four full-bridge converters modularly connected in Input-Parallel Output-Series configuration. Experimental verification shows that the system exceeds expectations and can be utilized and adapted to fit many pulsed power applications.
2

Overcoming Limitations of Serial Audio Search

Hidalgo, Isabela Cordeiro Ribeiro Moura 01 January 2012 (has links)
The typical approach for finding audio recordings, such as music and sound effects, in a database is to enter some textual information into a search field. The results appear summarized in a list of textual descriptions of the audio files along with a function for playing back the recordings. Exploring such a list sequentially is a time-consuming and tedious way to search for sounds. This research evaluates whether searching for audio information can become more effective with a user interface capable of presenting multiple audio streams simultaneously. A prototype audio player was developed with a user interface suitable for both search and browsing of a hierarchically organized audio collection. The audio recordings are presented either serially (serial output mode) or simultaneously (parallel output mode), spatially distributed in both vertical and horizontal planes. Users select individual recordings by simply pointing at its source location with a remote control. Two within-subjects experiments were conducted to compare the performance of the audio player's output modes in audio search tasks. The experiments differ in the maximum number of audio recordings played simultaneously - either four or six. In both experiments, search tasks were performed about 25% faster using parallel audio output than using serial output. Over 80% of participants preferred searching parallel output. The results indicate that using parallel output can be a valuable improvement to the current methods of audio search, which typically use only serial output.

Page generated in 0.0398 seconds