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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.
411

Break out Box for Transmission of Synchronous Video and CAN Data Streams over Gigabit Ethernet

Irestål, Erik January 2009 (has links)
Active safety systems for automobiles in the form of camera systems have evolved rapidly the last ten years, Autoliv Electronics in Linköping develops multiple such systems. In their development process there is a need for a Break out Box (BoB) to record and playback video and CAN data as if the camera system was used in an actual automobile. The aim of this thesis has been to develop a BoB for these camera systems. The work has been divided into three phases; identification of requirements, design of the BoB and implementation of a prototype. The project has addressed four known issues with the currently used BoB; bandwidth, modularity, synchronization and usability. The result is a new BoB which is based on an FPGA connecting to a PC over Gigabit Ethernet. The design is an extendible platform for multiple channels of video, CAN data, other serial data and future extensions. A prototype proves the design concept by successfully recording video for the Autoliv NightVision system onto a PC.
412

Reality by Design: Advertising Image, Music and Sound Design in the Production of Culture

Kurpiers, Joyce January 2009 (has links)
<p>This dissertation explores creative music, sound design and image production in the context of consumer culture (as defined by how its participants socialize in late-capitalist culture using commodities). Through the stylization of image, music and sound effects, advertisers communicate an abstract concept of a brand, and instantiate the brand through an audience member's heightened experience of the brand via the ad. Facilitated by socialized and mediatized frameworks for brand communications, branding is an embodied practice that relies on the audience member's participation with the brand through her/his real experience with an (audiovisual) advertisement. The effect of making the abstract brand tangible relies on successfully executing advertising objectives to create "impact" through stylized and often hyperreal representations of reality. At the same time, audience members' encounters with ads and branding practices represent bona fide experiences for them within American-capitalist cultural practices, and audience members take part in these practices as part of social participation and general making-sense of their everyday lives.</p><p>In late-capitalist consumer culture, the idea of the "consumer" operates within the liminal space of constructions of hyper-reality and the self. Through advertising, corporate interests mediate how people relate to and through commodities as consumers. Through ads, producers communicate an idea of a brand, that is, the collection and stylistic design of specific visual and sonic symbols, and the associated ideas, values or emotions that project an identity or persona about a company and its products or services. In attempts to increase the efficacy of their ads, ad producers fashion image, music and sound design specifically in ways they believe will generate "impact," that is, a physical, physiological or emotional response to audiovisual stimuli that are infused with symbolic meanings and values. </p><p>In their attempts to create effective ads, ad producers circumscribe identities of people based on demographics, behavior metrics, or a host of other measures intended to define what the industry calls "target audiences." With the belief that target audience members share wants, needs and values, ad producers build constellations of audiovisual signifiers that they believe will resonate with target audience members. These signifiers borrow from cultural narratives and myths to tell stories about brands and products, and communicate how people's lived experiences might be transformed through consumption practices. </p><p>With meticulous formulation of image, music and sound design, ad producers create a "hyperreality," that is exaggerated, heightened or stylized representation of reality. Through these carefully produced audio and visual artifacts, ad producers (re)circulate cultural narratives they believe communicate meaning and ideas of value, and make those abstract beliefs tangible through the audience member's sensorial experiences. With hyperreality grounded in an audience members' body and emotions, ad producers believe they can shape and direct audience members' ideas about their personal identities, and that of others and social groups. Additionally, ad image, music and sound design contribute to the naturalization of the ways people can socialize around branded identities and interconnect through commodities.</p> / Dissertation
413

A Study of Extracting Information from Neuronal Ensemble Activity and Sending Information to the Brain Using Microstimulation in Two Experimental Models: Bipedal Locomotion in Rhesus Macaques and Instructed Reaching Movements in Owl Monkeys

Fitzsimmons, Nathan Andrew January 2009 (has links)
<p>The loss of the ability to walk as the result of neurological injury or disease critically impacts the mobility and everyday lifestyle of millions. The World Heath Organization (WHO) estimates that approximately 1% of the world's population needs the use of a wheelchair to assist their personal mobility. Advances in the field of brain-machine interfaces (BMIs) have recently demonstrated the feasibility of using neuroprosthetics to extract motor information from cortical ensembles for more effective control of upper-limb replacements. However, the promise of BMIs has not yet been brought to bear on the challenge of restoring the ability to walk. A future neuroprosthesis designed to restore walking would need two streams of information flowing between the user's brain and the device. First, the motor control signals would have to be extracted from the brain, allowing the robotic prosthesis to behave in the manner intended by the user. Second, and equally important would be the flow of sensory and proprioceptive information back to the user from the neuroprosthesis. Here, I contribute to the foundation of such a bi-directional brain machine interface for the restoration of walking in a series of experiments in two animal models, designed to show the feasibility of (1) extracting locomotor information from neuronal ensemble activity and (2) sending information back into the brain via cortical microstimulation. </p><p>In a set of experiments designed to investigate the extraction of locomotor parameters, I chronically recorded from ensembles of neurons in primary motor (M1) and primary somatosensory (S1) cortices in two adult female rhesus macaques as they walked bipedally, at various speeds, both forward and backward on a custom treadmill. For these experiments, rhesus monkeys were suitable because of their ability to walk bipedally in a naturalistic manner with training. I demonstrate that the kinematics of bipedal walking in rhesus macaques can be extracted from neuronal ensemble recordings, both offline and in real-time. The activity of hundreds of neurons was processed by a series of linear decoders to extract accurate predictions of leg joints in three dimensional space, as well as leg muscle electromyograms (EMGs). Using a multi-layered switching model allowed us to achieve increased extraction accuracy by segregating different behavioral modes of walking.</p><p>In a second set of experiments designed to investigate the usage of microstimulation as a potential artificial sensory channel, I instructed two adult female Aotus trivirgatus (owl monkeys) about the location of a hidden food reward using a series of cortical microstimulation patterns delivered to primary somatosensory (S1) cortex. The owl monkeys discriminated these microstimulation patterns and used them to guide reaching movements to one of two targets. Here, owl monkeys were used which were previously implanted with electrode arrays of high longevity and stability. These monkeys were previously trained on a somatosensory cued task, which allowed a quick transition to microstimulation cueing. The owl monkeys learned to interpret microstimulation patterns, and their skill and speed of learning new patterns improved over several months. Additionally, neuronal activity recorded on non-stimulated electrodes in motor (M1), premotor (PMD) and posterior parietal (PP) cortices allowed us to examine the immediate neural responses to single biphasic stimulation pulses as well as overall responses to the spatiotemporal pattern. Using this recorded neuronal activity, I showed the efficacy of several linear classification algorithms during microstimulation. </p><p>These results demonstrate that locomotor kinematic parameters can be accurately decoded from the activity of neuronal ensembles, that multichannel microstimulation is a viable information channel for sensorized prosthetics, and that the technical limitations of combining these techniques can be overcome. I propose that bi-directional BMIs integrating these techniques will one day restore the ability to walk to severely paralyzed patients.</p> / Dissertation
414

M-ary Runlength Limited Coding and Signal Processing for Optical Data Storage

Licona-Nunez, Jorge Estuardo 12 April 2004 (has links)
Recent attempts to increase the capacity of the compact disc (CD) and digital versatile disc (DVD) have explored the use of multilevel recording instead of binary recording. Systems that achieve an increase in capacity of about three times that of conventional CD have been proposed for production. Marks in these systems are multilevel and fixed-length as opposed to binary and variable length in CD and DVD. The main objective of this work is to evaluate the performance of multilevel ($M$-ary) runlength-limited (RLL) coded sequences in optical data storage. First, the waterfilling capacity of a multilevel optical recording channel ($M$-ary ORC) is derived and evaluated. This provides insight into the achievable user bit densities, as well as a theoretical limit against which simulated systems can be compared. Then, we evaluate the performance of RLL codes on the $M$-ary ORC. A new channel model that includes the runlength constraint in the transmitted signal is used. We compare the performance of specific RLL codes, namely $M$-ary permutation codes, to that of real systems using multilevel fixed-length marks for recording and the theoretical limits. The Viterbi detector is used to estimate the original recorded symbols from the readout signal. Then, error correction is used to reduce the symbol error probability. We use a combined ECC/RLL code for phrase encoding. We evaluate the use of trellis coded modulation (TCM) for amplitude encoding. The detection of the readout signal is also studied. A post-processing algorithm for the Viterbi detector is introduced, which ensures that the detected word satisfies the code constraints. Specifying the codes and detector for the $M$-ary ORC gives a complete system whose performance can be compared to that of the recently developed systems found in the literature and the theoretical limits calculated in this research.
415

Melody spotting using hidden Markov models

Durey, Adriane Swalm 01 December 2003 (has links)
No description available.
416

Analysis and Optimization for Volume Holographic Recrording

Momtahan, Omid 07 July 2006 (has links)
Methods for analysis and optimization of volume holographic recording are presented for two main groups of applications. In the first group of applications (mainly storage systems), the designs and the techniques of volume holography are well known and the main optimization effort is finding the proper material to store the holograms. One of the results of this research is complete global optimization of dynamic range and sensitivity in two-center recording that is the best technique for persistent rewritable storage. For this purpose, a complete theoretical analysis as well as experimental demonstration is presented. Also, other effects and processes such as electron tunneling and recording at high temperature are considered for possible improvement of the dynamic range of the material. For the second group of applications (mainly holographic optical elements), the focus of this research is on analysis and optimization of the design of the volume holograms in contrast to material optimization. A new method (multi-grating method) is developed for the analysis of an arbitrary hologram that is based on the representation of the hologram as the superposition of several plane wave gratings. Based on this method, a new class of optical devices that integrates the functionalities of different optical elements into a simple volume hologram is introduced and analyzed. As a result, very compact, low cost, and easy to use devices such as portable spectrometers can be made with particular applications in biological and environmental sensing.
417

Nonuniform Distribution of Molecularly Thin Lubricant Caused by Inhomogeneous Buried Layers of Discrete Track Media

Fukuzawa, Kenji, 福澤, 健二, Muramatsu, Takuro, Amakawa, Hiroaki, Itoh, Shintaro, Zhang, Hedong 11 1900 (has links)
No description available.
418

Illumination compensation in video surveillance analysis

Bales, Michael Ryan 30 March 2011 (has links)
Problems in automated video surveillance analysis caused by illumination changes are explored, and solutions are presented. Controlled experiments are first conducted to measure the responses of color targets to changes in lighting intensity and spectrum. Surfaces of dissimilar color are found to respond significantly differently. Illumination compensation model error is reduced by 70% to 80% by individually optimizing model parameters for each distinct color region, and applying a model tuned for one region to a chromatically different region increases error by a factor of 15. A background model--called BigBackground--is presented to extract large, stable, chromatically self-similar background features by identifying the dominant colors in a scene. The stability and chromatic diversity of these features make them useful reference points for quantifying illumination changes. The model is observed to cover as much as 90% of a scene, and pixels belonging to the model are 20% more stable on average than non-member pixels. Several illumination compensation techniques are developed to exploit BigBackground, and are compared with several compensation techniques from the literature. Techniques are compared in terms of foreground / background classification, and are applied to an object tracking pipeline with kinematic and appearance-based correspondence mechanisms. Compared with other techniques, BigBackground-based techniques improve foreground classification by 25% to 43%, improve tracking accuracy by an average of 20%, and better preserve object appearance for appearance-based trackers. All algorithms are implemented in C or C++ to support the consideration of runtime performance. In terms of execution speed, the BigBackground-based illumination compensation technique is measured to run on par with the simplest compensation technique used for comparison, and consistently achieves twice the frame rate of the two next-fastest techniques.
419

Détection de textes dans des images issues d'un flux vidéo pour l'indexation sémantique

Wolf, Christian Jolion, Jean-Michel January 2005 (has links)
Thèse doctorat : Informatique : Villeurbanne, INSA : 2003. / Thèse rédigée en anglais. Introduction et conclusion générale en français. En 2ème partie, choix d'articles en français avec résumés, mots-clef et réf. bibliogr. Titre provenant de l'écran-titre. Bibliogr. p. 147-154. Publications de l'auteur p. 155-157.
420

The production of a video tape that will give Kutztown University students broader knowledge of campus activities

Fletcher, Wayne N. January 2000 (has links)
Thesis (M.S.)--Kutztown University of Pennsylvania, 2000. / Source: Masters Abstracts International, Volume: 45-06, page: 2708. Typescript. Abstract precedes thesis as, preliminary leaves i-ii.

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