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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.
131

Building Data Visualization Applications to Facilitate Vehicular Networking Research

Carter, Noah 01 May 2018 (has links)
A web app was developed which allows any internet-connected device to remotely monitor a roadway intersection’s state over HTTP. A mapping simulation was enhanced to allow researchers to retroactively track the location and the ad-hoc connectivity of vehicle clusters. A performance analysis was conducted on the utilized network partitioning algorithm. This work was completed under and for the utility of ETSU’s Vehicular Networking Lab. It can serve as a basis for further development in the field of wireless automobile connectivity.
132

Network journalism : journalistic practice in interactive spheres

Heinrich, Ansgard, n/a January 2008 (has links)
Today�s globalized network communication initiates new interactive formats, transforming not only the dissemination, but - increasingly - the production of news. The �one-way� flow of news from a news outlet to the audience has been replaced by a network structure. Following Castells� concept of the �network� (1996) as the central model of information structures, I perpetuate this paradigmatic shift and suggest that networks also transform the professional journalism sphere in many world regions. A revised sphere of journalism is taking shape in which an increasingly global flow of news is evolving and a multiple platform structure of journalism is taking shape in which boundaries between traditional media outlets of print, radio, and television and between national and �foreign� journalism are blurring. Furthermore, I argue that a globalized journalistic network sphere is emerging which involves �traditional� journalistic outlets and bloggers, media activists, so-called citizen journalists, or user-generated content providers alike. These new journalistic spheres of connectivity establish new (and continuous) links between journalists, their sources as well as their audiences. This fundamental change creates new professional levels of connectivity on one hand and on the other, has severe strategic and organizational implications for the management of print, broadcast and online news outlets. Within this new �network� sphere of journalistic practice, the roles of journalistic outlets change. This work suggests a framework that helps to understand journalistic organization today, with innovative work structures based on digital technologies transforming the character and in effect substituting the model of �top-down� journalism models by a model that is far more complicated. I argue that within an evolving global news sphere, information flows are multidirectional. Decentralization and non-linearity become the key parameters defining news flows at the beginning of the twenty-first century. The character of this network in the journalism sphere is transnational, crossmedia, and cross professions. Based on results of thirteen qualitative interviews with media practitioners in Germany, the US and the UK, I argue that a new geography of journalism is taking shape in which journalistic outlets are being transformed into nodes. These nodes are arranged in a dense net of information gathers, producers and disseminators and the interactive connections among them constitute what I want to call network journalism.
133

Testing digital receiver performance through an HF environment simulator

Pennington, Wayne Phillip January 2005 (has links)
Thesis (M.Eng.Sc.)--School of Electrical & Electronic Engineering , 2005.
134

Novel turbo-equalization techniques for coded digital transmission

Dejonghe, Antoine 10 December 2004 (has links)
Turbo-codes have attracted an explosion of interest since their discovery in 1993: for the first time, the gap with the limits predicted by information and coding theory was on the way to be bridged. The astonishing performance of turbo-codes relies on two major concepts: code concatenation so as to build a powerful global code, and iterative decoding in order to efficiently approximate the optimal decoding process. As a matter of fact, the techniques involved in turbo coding and in the associated iterative decoding strategy can be generalized to other problems frequently encountered in digital communications. This results in a so-called turbo principle. A famous application of the latter principle is the communication scheme referred to as turbo-equalization: when considering coded transmission over a frequency-selective channel, it enables to jointly and efficiently perform the equalization and decoding tasks required at the receiver. This leads by the way to significant performance improvement with regard to conventional disjoint approaches. In this context, the purpose of the present thesis is the derivation and the performance study of novel digital communication receivers, which perform iterative joint detection and decoding by means of the turbo principle. The binary turbo-equalization scheme is considered as a starting point, and improved in several ways, which are detailed throughout this work. Emphasis is always put on the performance analysis of the proposed communication systems, so as to reach insight about their behavior. Practical considerations are also taken into account, in order to provide realistic, tractable, and efficient solutions.
135

Multi-standard low-power base-band digital receiver, enhanced for HSDPA /

Martelli, Chiara, January 2006 (has links)
Originally presented as the author's thesis (Swiss Federal Institute of Technology), Diss. ETH No. 16683. / Summary in Italian and English; text in English. Includes bibliographical references (p. 171-177).
136

Application of Turbo-Codes in Digital Communications

Haj Shir Mohammadi, Atousa January 2001 (has links)
This thesis aims at providing results and insight towards the application of turbo-codes in digital communication systems, mainly in three parts. The first part considers systems of combined turbo-code and modulation. This section follows the pragmatic approach of the first proposed such system. It is shown that by optimizing the labeling method and/or modifying the puncturing pattern, improvements of more than 0. 5 dB insignal to noise ratio (SNR) are achieved at no extra cost of energy, complexity, or delay. Conventional turbo-codes with binary signaling divide the bit energy equally among the transmitted turbo-encoder output bits. The second part of this thesis proposes a turbo-code scheme with unequal power allocation to the encoder output bits. It is shown, both theoretically and by simulation, that by optimizing the power allocated to the systematic and parity check bits, improvements of around 0. 5 dB can be achieved over the conventional turbo-coding scheme. The third part of this thesis tackles the question of ``the sensitivity of the turbo-code performance towards the choice of the interleaver'', which was brought up since the early studies of these codes. This is the first theoretical approach taken towards this subject. The variance of the bound is evaluated. It is proven that the ratio of the standard deviation over the mean of the bound is asymptotically constant (for large interleaverlength, N), decreases with N, and increases with SNR. The distribution of the bound is also computationally developed. It is shown that as SNR increases, a very low percentage of the interleavers deviate quite significantly from the average bound but the majority of the random interleavers result in performances very close to the average. The contributions of input words of different weights in the variance of performance bound are also evaluated. Results show that these contributions vary significantly with SNR and N. These observations are important when developing interleaver design algorithms.
137

Application of Turbo-Codes in Digital Communications

Haj Shir Mohammadi, Atousa January 2001 (has links)
This thesis aims at providing results and insight towards the application of turbo-codes in digital communication systems, mainly in three parts. The first part considers systems of combined turbo-code and modulation. This section follows the pragmatic approach of the first proposed such system. It is shown that by optimizing the labeling method and/or modifying the puncturing pattern, improvements of more than 0. 5 dB insignal to noise ratio (SNR) are achieved at no extra cost of energy, complexity, or delay. Conventional turbo-codes with binary signaling divide the bit energy equally among the transmitted turbo-encoder output bits. The second part of this thesis proposes a turbo-code scheme with unequal power allocation to the encoder output bits. It is shown, both theoretically and by simulation, that by optimizing the power allocated to the systematic and parity check bits, improvements of around 0. 5 dB can be achieved over the conventional turbo-coding scheme. The third part of this thesis tackles the question of ``the sensitivity of the turbo-code performance towards the choice of the interleaver'', which was brought up since the early studies of these codes. This is the first theoretical approach taken towards this subject. The variance of the bound is evaluated. It is proven that the ratio of the standard deviation over the mean of the bound is asymptotically constant (for large interleaverlength, N), decreases with N, and increases with SNR. The distribution of the bound is also computationally developed. It is shown that as SNR increases, a very low percentage of the interleavers deviate quite significantly from the average bound but the majority of the random interleavers result in performances very close to the average. The contributions of input words of different weights in the variance of performance bound are also evaluated. Results show that these contributions vary significantly with SNR and N. These observations are important when developing interleaver design algorithms.
138

Pitch-synchronous processing of speech signal for improving the quality of low bit rate speech coders

Ertan, Ali Erdem 01 June 2004 (has links)
No description available.
139

New media uses and dependency effect model exploring the relationship between new media use habit, dependency relation, and possible outcomes /

Cho, Yoonwhan, January 2009 (has links)
Thesis (Ph. D.)--Rutgers University, 2009. / "Graduate Program in Communication, Information and Library Studies." Includes bibliographical references (p. 149-153).
140

Applications of wavelets to nonlinear wave analysis and digital communication /

Yi, Eun-jik, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 135-143). Available also in a digital version from Dissertation Abstracts.

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